【Objective】This study aims to investigate the residual efficacy and duration of various trunk-injected agents on masson pine (Pinus massoniana). Assess transport distribution, residue dynamics, and control effects on pine wilt disease. Evaluate 5% (mass fraction) emamectin benzoate soluble liquid, 5% abamectin emulsion, and 1% emamectin benzoate-9% imidacloprid soluble liquid agents.【Method】Sampled at different parts of the pine tree in layers. Analyzed residue dynamics in the tree using liquid chromatography-mass spectrometry (LC-MS). Quantitatively analyzed the translocation, distribution, and residue dynamics of the chemical within pine trees. Following trunk injection, inoculate the pines and design a secondary inoculation to simulate continuous nematode infestation; continuously monitor and record disease development to evaluate the chemical's long-term protective efficacy.【Result】Three trunk-injected agents effectively reached various parts of Pinus massoniana, with the main trunk showing the highest residue levels and branches less so. Residues generally lasted about three years, peaking in the first year, then declining. The 5% emamectin benzoate had the best transport and residue, maintaining a 24.609 mg/kg residue level after three years, and remained at a 37.50% control efficacy after a second inoculation. Abamectin showed rapid degradation, with no residue detected in top branches after three years, and only 12.50% efficacy after a second inoculation. The 1% emamectin benzoate-9% imidacloprid had lower nematode control, resulting in the earliest onset. Higher doses effectively increased residue levels, with 60 mL 5% emamectin benzoate reaching 33.900 mg/kg after one year, much higher than 30 mL 5% emamectin benzoate's 2.405 mg/kg. Injection methods had little effect on residue distribution at 1 and 2 a.【Conclusion】Three trunk-injected agents can be transported to all parts of the tree after injection. Compared with the other two, 5% emamectin benzoate has higher transport efficiency and residual amount, making it the preferred agent for long-term prevention and control of pine wilt disease. All three agents can effectively prevent pine wilt disease for a relatively long time after injection. The residual amount and control effect are still significant one or two years after injection, but the control effect decreases significantly three years after injection.
【Objective】Injecting agents into pine trees to prevent pine wilt disease is an effective control measure. This study aimed to develop more efficient and fast-delivery agents by combining two different drugs to create a novel microemulsion. The virulence activity of this combined (3% fluopyram-5% emamectin benzoate) microemulsion against Bursaphelenchus xylophilus and its potential for controlling pine wilt disease were explored.【Method】The nematocidal effects of the newly developed combined microemulsion, along with two commonly used agents for pine wilt disease-5% emamectin benzoate microemulsion and 5% avermectin emulsifiable concentrate-were assessed using the insect immersion method. B. xylophilus was treated with lethal concentrations (LC10 and LC30) of each agent to determine their impact on nematode reproduction. Three agents were injected into the trunks of Pinus massoniana trees in the forest to observe agent absorption and tree sensitivity to successfully absorbed agents. After 90 days of injection, samples of the treated trees were collected to analyze the dynamic distribution of drug transport within the tree body. Additionally, 100 days after inoculation, the treated trees were artificially inoculated with B. xylophilus to observe and statistically analyze the control effects of each agent on pine wilt disease.【Result】The LC50 values after 24 hours of treatment with the 3% fluopyram-5% emamectin benzoate microemulsion, 5% emamectin benzoate microemulsion, and 5% avermectin emulsifiable concentrate on pine wood nematodes were 2.644 0, 27.678 4, and 42.891 1 mg/L, respectively. Among the tested agents, the 3% fluopyram-5% emamectin benzoate microemulsion exhibited the strongest nematocidal activity. The population reproduction of nematodes treated with low concentrations of the agents was significantly lower than the control group. Seven days after injection, both the self-made combined microemulsion and 5% avermectin emulsifiable concentrate were fully absorbed by the tree, whereas absorption of the 5% emamectin benzoate microemulsion was more limited. After 180 days, the self-made combined microemulsion showed minimal sensitivity to the tree, with slight discoloration at the injection point, while the 5% avermectin emulsifiable concentrate caused significant discoloration of the xylem at the injection site. After 90 days, residual concentrations of all agents were detected at the top of the tree. The highest residual concentration of fluopyram (0.13 mg/kg) was found 0.5 m below the injection point in the combined 3% fluopyram-5% emamectin benzoate microemulsion, while emamectin benzoate had a residual concentration of 0.07 mg/kg, and 5% avermectin's residual concent ration had 0.1 mg/kg. The highest residual concentrations of all agents were observed 0.5 m above the injection point, with fluopyram in the combined microemulsion reaching 55.65 mg/kg, significantly higher than the other agents. Overall, the residual concentration of fluopyram was higher than that of emamectin benzoate in the combined microemulsion and higher than 5% avermectin emulsifiable concentrate. Inoculation with pine wood nematodes in mid-July showed that, 270 days after inoculation, the trees treated with the agents remained healthy, while untreated trees exhibited signs of infection 100 days post-inoculation. All agents effectively prevented the onset of pine wilt disease.【Conclusion】The toxicity analysis of the new self-made combined agent demonstrates its strong nematocidal effect, good absorbability after injection into P. massoniana, and mild sensitivity to the tree. It also exhibits excellent transport ability within the tree and provides effective prevention against pine wood nematode infection. Further optimization of the formula and large-scale application in forest management is recommended.
【Objective】This study aims to identify suitable metabolites for the early diagnosis of pine wilt disease (PWD). To achieve this, the metabolome of stem segments from Pinus massoniana infected by different nematodes was analyzed, with the goal of improving the prevention and control of PWD.【Method】With four-year-old P. massoniana trees with similar growth characteristics were inoculated with three different nematode species, each with varying pathogenicity. These included the highly virulent Bursaphelenchus xylophilus (nematode strain FCBX), the highly virulent B. mucronatus (nematode strain BM7), and the non-virulent B. mucronatus (nematode strain FCBM). These nematodes were isolated and cultured in the Forest Pathology Laboratory of Nanjing Forestry University. Inoculation of P. massoniana trees with these nematodes were conducted under controlled conditions to assess their virulence. A sterile water control group (CK) was also included. Three days after injection, the metabolome of stem segments from P. massoniana was analyzed using ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Principal component analysis (PCA) was used to ensure quality control of the metabolomic data. Metabolites with specific expression following B. xylophilus inoculation were identified through a combination of P-values and variable importance in projection (VIP) scores. Targeted detection and validation of these metabolites were conducted using ultra-performance liquid chromatography (UPLC).【Result】The three nematode species exhibited significant differences in virulence toward P. massoniana. Metabolomic analysis of stem segments revealed reliable results. One key finding was that 7-dehydrocholesterol was a common differential metabolite across the comparative metabolomes of P. massoniana inoculated with different nematodes. Levels of this compound were measured using UPLC on the 3rd, 7th, and 21st days after inoculation. It was detectable only in the group inoculated with the highly virulent B. xylophilus (nematode strain FCBX), with concentrations of 4.09, 66.77, and 28.8 μg/g, respectively. 7-dehydrocholesterol was undetectable in the sterile water control group (CK), as well as in the groups treated with either highly virulent B. mucronatus (nematode strain BM7) or non-virulent B. mucronatus (nematode strain FCBM).【Conclusion】7-dehydrocholesterol, identified through the metabolomic profiling of P. massoniana, was found to be a specific metabolite following early infection by B. xylophilus. This metabolite's specificity allows it to distinguish B. xylophilus infection from infections caused by other nematodes. Therefore, the detection of 7-dehydrocholesterol levels could serve as an effective tool for the early diagnosis of pine wilt disease.
【Objective】As the newly confirmed vector of pine wood nematode (Bursaphelenchus xylophilus) in northeast China, longicorn (Monochamus saltuarius) poses a critical threat to coniferous ecosystems.This study aimed to compare the operational efficacy of pheromone traps and trunk-type capture devices in catching the beetle in the wild, thereby establishing a scientific foundation for breaking the nematode transmission cycle.【Method】In Maoershan Experimental Forest Farm of Northeast Forestry University (Shangzhi City, Heilongjiang Province)the catching experiments using pheromone trapping and trunk-type catcher were conducted at the same time,and the catching species, the sound rate of catching longicorn and the ratio of female to male in M. saltuarius by different means were compared. Whether the captured M. saltuarius have adult feeding were determined based on the developmental status of the female ovaries. In the pheromone trapping experiment lure Zhongjiesifang and F8 developed for M.alternatus, lure ZL-1 developed for M. saltuarius were used and the trapping effects of the different lures for M. saltuarius were compared.【Result】There was a little difference in the catching species between by two means, and M. saltuarius was the dominant species with nearly same ratio of female to male, but the sound rate of the catching longicorn by trunk-type catcher was higher than that by pheromone trapping. The ovaries of the females M. saltuarius from the pheromone trapping had reached the fourth stage of development, indicating that these females already had adult feeding, while the ovaries of the females captured by trunk-type catcher before July were in the first stage of development, indicating these females had no adult feeding. The trapping activity of lure F8 on M. saltuarius in the wild was slightly lower than that of lure of ZL-1 and Zhongjiesifang, but there was no difference in the trapping activity for both sexes among the three lures.【Conclusion】M. saltuarius is a dominant species in Monochamus in the experimental area, and as the vector of B. xylophilus, its population dynamics need to be closely monitored. The pheromone trapping with long persistent period is suitable for monitoring and controlling population of M. saltuarius, but it cannot effectively control the spread of B. xylophilus due to the catching M. saltuarius already adult feeded. The trunk-type catcher can capture M. saltuarius that just emerge from its eclosion hole on the trunk before having adult feeding and spreading B. xylophilus, thus it is suitable for future development as a means to control the spread of B. xylophilus. In addition,the trunk-type catcher is also suitable for collecting live longicorn in scientific research because of high sound rate of captured beetls.
【Objective】This study aimed to evaluate the conduction residues and disease prevention efficacy of different chemicals in pine trees following trunk injection and identify trunk injections with strong persistence and effective control, providing a theoretical basis for the use of trunk injections to prevent pine wood nematode (Bursaphelenchus xylophilus).【Method】The insecticidal efficacy of 5% emamectin benzoate soluble liquid, 5% avermectin emulsifiable concentrate, and 1% emamectin benzoate-9% imidacloprid soluble liquid on B. xylophilus was assessed using the dipping method. The sublethal concentration (LC20) of each pesticide was applied to Botrytis cinerea and inoculated with B. xylophilus to assess their effects on nematode feeding and reproduction. Subsequently, these pesticides were injected into the trunks of Pinus massoniana in the forest, and the translocation of residues within the trees was analyzed one year and 660 days after injection. In June of the second year (2022), P. massoniana was artificially inoculated with B. xylophilus, and the disease prevention effect was observed and statistically analyzed one year after the injection.【Result】After 24 hours of treatment, the LC50 values for the three agents were determined to be 10.879 8 mg/L, 57.008 7 mg/L, and 93.693 9 mg/L, respectively. When B. cinerea was inoculated with nematodes and treated with sublethal concentrations (LC20) of these pesticides, all three significantly inhibited nematode feeding rates and reduced nematode populations (333, 466, and 500 nematodes, respectively, compared to 47 766 nematodes/dish in the control). One year after injection, the pesticides were found to translocate upward from the injection sites in P. massoniana. Residual amounts were detected in the upper branches, except for the 5% avermectin emulsifiable concentrate. Among the treatments, the 5% emamectin benzoate soluble liquid exhibited the lowest residual concentration at 0.006 3 mg/kg, while the mixed formulation showed the highest residual concentrations of imidacloprid (0.213 0 mg/kg) and emamectin benzoate (0.082 3 mg/kg). These compounds accumulated at higher levels in areas 2.0 m and 0.5 m from the injection points, with concentrations of 12.863 6 mg/kg and 128.395 2 mg/kg, respectively. After 660 days, residual concentrations of all formulations decreased, although residues remained detectable in the upper branches. The highest residual compound concentration was 0.125 1 mg/kg, followed by 5% emamectin benzoate soluble liquid at 0.074 1 mg/kg, and 5% avermectin emulsifiable concentrate at 0.012 4 mg/kg. Unlike the results after one year, where certain areas exhibited the highest residual concentrations for the 5% emamectin benzoate soluble liquid and the mixed formulation, the residual concentrations decreased with height over time. Pine trees inoculated with B. xylophilus 450 days post-injection and analyzed 75 days after inoculation showed a 100% disease prevention rate with all three pesticides. Continuous observation revealed that 5% avermectin emulsifiable concentrate had a significantly better preventive effect.【Conclusion】The three agents-5% emamectin benzoate soluble liquid, 5% avermectin emulsifiable concentrate, and 1% emamectin benzoate-9% imidacloprid soluble liquid—not only exhibit strong toxicity to B. xylophilus but also demonstrate good translocation and persistence in P. massoniana following trunk injection. Additionally, these injections maintain a strong preventive effect against pine wood nematode infection even into the second year. Among the agents tested, 5% avermectin emulsifiable concentrate shows the best overall control efficacy and should be considered for large-scale application in forest management.
【Objective】Pinus massoniana (masson pine), a native conifer species endemic to southern China’s mountainous regions, holds significant economic and ecological value. However, the spread of pine wood nematode disease (PWD) has necessitated breeding programs to enhance its resistance, and to provide critical germplasm for PWD-resistant breeding. 【Method】A total of 725 half-sib progenies (from 51 families) derived from PWD-resistant P. massoniana trees were collected across five provinces (cautonomous region). Resistance was assessed via artificial inoculation with 5 000 pine wood nematodes per seedling. Genome-wide association studies (GWAS) were performed by integrating phenotypic data from inoculation assays with targeted sequencing data generated using a 101.6 K liquid-phase probe panel. 【Result】Four highly resistant and ten resistant families were identified as valuable germplasm resources. Statistical analyses revealed that mixed linear model (MLM) obtained five significant SNPs (phenotypic variance explained, PVE 7.69%-11.24%). General linear model (GLM) obtained four significant SNPs (total PVE 5.96%). BLINK model obtained eleven significant SNPs (PVE 12.86%-26.43%). Nine candidate genes were functionally annotated, including P450 family proteins, pectin methylesterase inhibitors (PMEIs), and others. These genes likely regulate post-invasion immune responses by modulating cell wall structure and membrane protein recognition. 【Conclusion】Fourteen P. massoniana resistant families can serve as valuable breeding materials for disease-resistant varieties. Nine candidate disease-resistant genes identified through GWAS will contribute to elucidating the disease resistance mechanisms of P. massoniana and facilitating early selection of disease-resistant varieties.
【Objective】The study aims to investigate the species diversity and biomass spatial patterns of six dominant community types in Yuyao’s ecological welfare forests, and to elucidate the impacts of environmental factors on forest biomass and biodiversity. 【Method】Based on 2020 survey data from 175 sample plots in Yuyao City, Zhejiang Province, this study analyzed tree and shrub layer characteristics including species composition, tree height, DBH (diameter at breast height), basal diameter, and coverage. Combined with stand factors, climatic data, and soil parameters, we systematically examined the spatial distribution patterns of species diversity and biomass across different communities, along with their relationships with environmental variables. 【Result】(1) The total standing biomass of ecological welfare forests in Yuyao reached 6.048 million tons, with an average biomass density of 163.61 t/hm2. (2) Significant spatial heterogeneity in biomass distribution was observed, showing a distinct “north-high, south-low pattern”. Biomass demonstrated significant positive correlations with altitude (P<0.05), latitude (P<0.05), mean tree height (P<0.05), DBH (P<0.05), precipitation(P<0.05), soil nitrogen content (P<0.05), and soil phosphorus content(P<0.05), while exhibiting significant negative correlation with soil bulk density(P<0.05). (3)The Shannon-Wiener diversity index varied significantly among communities (P<0.05), showing the following descending order: broad-leaved forests > coniferous-broadleaved mixed forests > bamboo forests > Chinese fir forests > pine forests > shrublands. The diversity index displayed significant positive correlations with canopy closure (P<0.05), mean DBH (P<0.05), soil nitrogen content(P<0.05), soil organic matter content (P<0.05), and soil moisture content (P<0.05).【Conclusion】The spatial heterogeneity of biomass in major communities of Yuyao’s ecological welfare forests exhibits significant geographical stratification characteristics, with its spatial distribution governed by the integrated effects of multidimensional environmental factors. Specifically, it is primarily driven by the coupling effects of topographic factors (altitude, latitude), stand characteristics (mean DBH, tree height), and soil conditions (soil nitrogen, phosphorus, and bulk density). Community species diversity demonstrates differential responses to environmental gradients: broad-leaved forests maintain the maximum Shannon-Wiener index through synergistic effects between canopy closure and soil fertility (organic matter, moisture content). Precipitation-driven forest biogeochemical processes show significant correlations with community biomass accumulation.
【Objective】This study investigated the ornamental characteristics of fruit color in 30 ornamental crabapple cultivars, aiming to provide references for breeding and landscape applications. 【Method】Seasonal variations in fruit color were observed to classify cultivars into color groups and determine optimal viewing periods. The diversity and temporal complementarity of fruit color within the cultivar group were systematically analyzed.【Result】The results showed that:cluster analysis of fruit color parameters (Euclidean distance = 3) categorized the cultivars into five color series: green (10.0%), yellow (16.6%), orange (6.7%), red (60.0%), and purple (6.7%).Brightness values followed the hierarchy: green series (67.7) > yellow series (64.9) > orange series (46.5) > red series (32.6) > purple series (20.5). The optimal fruit viewing period was at the same tinie frame in autumn (September-November), with cultivar diversity index showing a normal distribution pattern: early-autumn (50.0%), mid-autumn (60.0%), and late-autumn (63.3%). The average optimal viewing duration was 1.5 months, with the shortest being 1 month and the longest neaching 3 months. Based on color vividness, surface gloss, and spot presence, the ornamental value of the 30 cultivars was classified into three tiers (A-C). Top-tier (A) cultivars included Malus ‘Han Yancui’, M. ‘Red Jewel’, M. ‘Hong Ou’, M. ‘Hong Zhenzhu’, M. ‘Hong Tu’, M. ‘Sheng Xia’, M. ‘Shiyue Guanghui’, and M. ‘Yu Ji’. 【Conclusion】The crabapple cultivars exhibit high fruit color diversity, extended group viewing seasons and individual viewing periods. These multi-colored, multi-seasonal cultivars provide significant support for autumn tourism and ornamental applications, demonstrating substantial value for promoting the crabapple tourism industry.
【Objective】To characterize the community structure and diversity of Carabidae insects in different habitats in broad-leaved mixed forest and adjacent Pinus koraiensis plantation forest following farmland conversion to forests, to identify indicator or monitor species to investigate the edge effect in the study area and to elucidate the role of P. koraiensis plantation forests in the maintenance of diversity.【Method】During May to September in 2017 and 2018, the study area was divided into three habitats—Pinus koraiensis plantation forest, ecotone, and broad-leaved mixed forest-based on distance gradients. Using the pitfall trapping method, 27 pitfall traps were deployed in each habitat to continuously trap and collect Carabidae insects over two years. Collected specimens were subsequently classified and identified based on morphological characteristics. One-way ANOVA was used to assess differences in Carabidae insects community structure and α-diversity indices. Pearson correlation coefficients were employed to examine correlations among these α-diversity indices. Hill diversity rarefaction and extrapolation analyses were conducted to characterize trends in the number of species, common species, and dominant species in relation to the number of individuals. For β-diversity, NMDS, PERMANOVA, and SIMPER were applied. Indicator species were identified using IndVal indices.【Result】A total of 3 755 Carabidae insects of 41 species from nine subfamilies were captured, there were 1 037 Carabidae insects of 34 species from eight subfamilies in the P. koraiensis plantation forest, 1 643 Carabidae insects of 38 species from nine subfamilies in ecotone, 1 075 Carabidae insects of 32 species from nine subfamilies in the broad-leaved mixed forest, there were all 29 species in three habitats. The number of individuals of Carabinae in broad-leaved mixed forest was significantly higher than that the other two habitats (P<0.05), the number of individuals of Harpalinae in the P. koraiensis plantation forest was significantly higher than in that broad-leaved mixed forests (P<0.05), the number of individuals of Licininae in ecotone was significantly higher than that in the broad-leaved mixed forests (P<0.05), the number of individuals of Platyninae in ecotone was significantly higher than that in the other two habitats (P<0.05). The number of species of Harpalinae and Panagaeinae in broad-leaved mixed forests were significantly lower than that in the other two habitats (P<0.05), the number of species of Pterostichinae in ecotone was significantly higher than that in the other two habitats (P<0.05). Rarefaction and extrapolation of Hill diversity showed that although ecotone had the highest number of species, P. koraiensis plantation forest had the highest number of common and dominant species. Among α diversity indices, the number of individuals in ecotone was significantly higher than that in the other two habitats (P<0.05), the number of species, Chao1 index and ACE index in ecotone were significantly higher than those in broad-leaved mixed forests (P<0.05), Margalef index in broad-leaved mixed forests was significantly lower than that in the other two habitats (P<0.05), and many indices were are significantly correlated with the number of species (P<0.05). NMDS and PERMANOVA showed significant differences in community structure in different habitats (P<0.05), SIMPER showed Licininae and Carabinae had large contribution to differences in different community structure. IndVal index showed no indicator and monitor species in P. koraiensis plantation forest,four monitor species in ecotone, and two indicator species in broad-leaved mixed forest. The edge effect was weakly positive overall in the study area.【Conclusion】Differences in the community structure and diversity of Carabidae insects across habitats suggest distinct habitat preferences among different taxa, which are closely linked to their ecological behaviors. Notably, the finding that Carabidae insects exhibited a strong tendency to inhabit ecotones further corroborates with the presence of a positive edge effect for this group in the study area. The highest number of common and dominant species observed in P. koraiensis plantation forests indicates that these plantations play a critical role in maintaining local biodiversity. Additionally, given the multiple indicator and monitoring species identified in both ecotones and broad-leaved mixed forests, a multi-species monitoring approach is recommended to effectively assess habitat conditions.
【Objective】The study determined the core biological function of the effector protein GyHGSRE1 secreted by the Gymnosporangium yamadae haustoria. This work provides foundational data for elucidating the molecular mechanisms of G. yamadae effector protein.【Method】The haustorial transcriptome of G. yamadae prioritized GyHGSRE1 as a highly expressed effector (FPKM = 117.92). MEME (http://meme-suite.org/) predicted its two-dimensional structure, while Tencent AI (https://drug.ai.tencent.com) generated the three-dimensional model. Real-time PCR quantified GyHGSRE1 expression level during fungal infection. Yeast secretion assays validated the signal peptide’s secretory capacity. Transient expression via Agrobacterium tumefaciens assessed GyHGSRE1 function in Nicotiana benthamiana and apple (Malus domestica) leaves.【Result】GyHGSRE1 contains an N-terminal serine-rich signal peptide. qRT-PCR demonstrated peak expression during haustorium maturation and spore development (pycniosporophores/aeciospores). The protein was localized to plant cell cytoplasm and nuclei, triggering cell death and immune responses in leaf cells of N. benthamiana. Full-length GyHGSRE1 induced cell death in apple leaves, but deletion of the signal peptide attenuated this activity.【Conclusion】The glycine-serine-rich atypical effector GyHGSRE1 exhibits dual localization and cell necrosis-inducing effects across plant species, implying broad-spectrum elicitor potential. Its expression correlates with critical infection stages (host colonization and sporulation). The signal peptide may mediate functional specificity, likely influencing host-pathogen recognition.
【Objective】Nature reserves face conflicts between ecological conservation and economic development. By establishing ecological networks to maintain the integrity, connectivity, stability, and biodiversity of ecological sources, species recovery and habitat restoration can be ensured. This approach provides a scientific foundation for the protection and development of the Helan Mountains.【Method】Taking the Helan Mountain as the study area, we identified ecologically valuable forest lands as core areas using the morphological spatial pattern analysis (MSPA). Ranked core areas by connectivity significance through landscape connectivity assessment.Extracted six resistance factors and simulated ecological corridors via the minimum cumulative resistance (MCR) and the gravity models. Identified ecological nodes through hydrological analysis to construct the ecological security network.【Result】The Helan Mountains comprises 15 significant ecological sources covering with a total area of 44 766 hm2, which are concentrated in the central and southern regions. Thirty-one general ecological corridors and 16 critical ecological corridors were identified within the area, effectively connecting all ecological sources and ensuring species exchange. Ninety-one ecological nodes were identified, including 43 temporary rest points, 35 strategic points, and 13 breakpoints; most of the ecological security networks within the study area shows high connectivity and integrity.【Conclusion】The ecological security pattern of the Helan Mountains can be zoned into core protection areas, ecological buffer zones, and sustainable use areas. Differentiated management strategies for different areas can provide references for optimizing the ecological functions of the nature reserve and spatial coordination planning, promotes the protection of biodiversity and sustainable development of ecosystems in the nature reserve.
【Objective】In the context of rapid urbanization, establishing an ecological security pattern (ESP) for natural protected areas (NPAs) is crucial for enhancing connectivity and guiding territorial spatial ecological restoration practices.【Method】Taking the Yangtze River Delta urban agglomeration (YRDUA) as the study area, ecological sources were identified based on ecosystem service value by integrating morphological spatial pattern analysis (MSPA) with data on existing NPAs. A comprehensive resistance surface was constructed using the analytic hierarchy process (AHP), and ecological corridors were extracted via the minimum cumulative resistance (MCR) model. There by constructing an ESP with the model of “Ecological sources-Resistance surface-Ecological corridors”. Connectivity characteristics of NPAs were systematically assessed to pinpoint key areas for territorial spatial ecological restoration. 【Result】The study identified 145 ecological sources, 323 ecological corridors, and 34 potential corridors. Critical restoration targets included one low-security zone, 179 ecological pinch points, and 35 ecological barriers. 【Conclusion】This research reveals significant connectivity challenges among NPAs in the YRDUA and proposes connectivity enhancement strategies within territorial spatial planning: (1) Breaking administrative boundaries to promote cross-regional ecological corridor development. (2) Implementing differentiated restoration in priority zones. These findings provide scientific support for optimizing NPA connectivity and regional ecological restoration.
【Objective】This study explores the trade-offs, synergies, and driving factors among the ecosystem services in Baishanzu National Park, providing support for formulating scientific ecological protection and management strategies.【Method】We quantified four ecosystem services-vegetation net primary productivity (NPP), soil conservation (SC), habitat quality (HQ), and water yield (WY)-in Baishanzu National Park from 2000 to 2020 by using the InVEST and the CASA models. Spearman correlation and geographically weighted regression (GWR) were used to analyze the relationships of trade-offs and synergies among ecosystem services, while the random forest modeling was used to explore the dominant drivers and marginal effects.【Result】From 2000 to 2020, the NPP in Baishanzu National Park nature reserve increased, the HQ declined slightly, and the SC and the WY decreased initially before rising. Spatially, the NPP, the SC, and the WY exhibited similar patterns with high values in central/northwestern regions, whereas the HQ peaked in central/northern areas. The increase in temperature had a significant impact on the relationship between the HQ and the NPP, while precipitation, elevation, and slope had a significant impact on the relationship between the SC and the WY.【Conclusion】The four ecosystem services demonstrated an overall synergy but showed obvious spatial heterogeneity. Climate change was the primary driver of trade-offs/synergies, followed by the degree of vegetation coverage and terrain factors. This indicates that when formulating ecological strategies must therefore account for interactions among these key factors and their potential nonlinear effects.
Ecosystem services and landscape ecological risks are gradually evolving from independent scientific propositions to a hot topic of linked research, and the results of research on the integration of their related effects can provide important insights for the theory and practice of ensuring ecological security and enhancing human well-being. Based on the main research results that link ecosystem services with landscape ecological risks in recent years. We elaborate on the connotation of the relationship between ecosystem service values, functions and landscape ecological risks and the characterization of their related effects. We also summarize the methods for assessing the correlation effects of ecosystem services and landscape ecological risks in quantity, spatial and temporal dimensions. We further outline the applications of the correlation effects in the fields of ecological security pattern construction, sustainable development path design, land remediation effectiveness and potential benefit assessment. We proposed that accurately identifying key spatial and temporal scales, exploring driving factors and correlation mechanisms, advancing the combined analysis of trade-offs and synergies, and expanding technological methods and practical scenarios are the research directions that need to be strengthened in the future.
【Objective】Pinus sylvestris var. mongholica, a species with notable environmental adaptability, has been extensively cultivated in the Three-North regions of China. In recent years, a novel disease causing needle blight has emerged in P. sylvestris var. mongholica plantations in Hebei and Inner Mongolia. This study aimed to identify the causal pathogen, biological characteristics, and evaluate fungicide efficacy to establish scientifically grounded control measures for this disease.【Method】Isolates were obtained from both conidia and diseased tissues. Morphology combined with phylogeny identified the strains and the pathogen was determined by Koch postulates. The effects of different carbon source media, pH, photo period, and temperature conditions on mycelial growth were systematically investigated. Mycelial growth rate method was used to study the inhibitory effect of 10 fungicides on pathogen and calculated the value of EC50 through virulence regression analysis.【Result】A total of 84 fungal strains were isolated from symptomatic needles, among which isolates Z-17, Z-21, Z-22 and Z-24 exhibited pathogenicity toward P. sylvestris var. mongholica, reproducing disease symptoms consistent with field observations. Conidia of these strains were subspherical, hyaline, septate, smooth, nearly cylindrical to oval, measuring (4.2-10.3) μm × (2.5-6.3) μm, aligning with the morphological features of fruiting bodies observed on necrotic needles. Phylogenetic analysis demonstrated that the four strains clustered with Sydowia polyspora with 100% bootstrap support. Based on these findings, S. polyspora was identified as the causal agent of needle blight in P. sylvestris var. mongholica. Biological characterization revealed that glucose provided the optimal carbon source for mycelial growth, whereas starch was the least utilized. Mycelial growth occurred within a pH range of 3-9, with optimal growth at pH 5. Continuous 24 h light exposure most favorably supported mycelial development, and the lethal temperature for mycelia was 55 ℃. Fungicide screening indicated that 25%(v/v) myclobutanil (EC50 = 0.003 9 mg/L), 45%(v/v) prochloraz (EC50 = 0.044 3 mg/L), and 10%(m/m) difenoconazole (EC50 = 0.047 5 mg/L) exhibited the strongest inhibitory effects against S. polyspora. In contrast, 80%(m/m) thiram showed the poorest efficacy, with an EC50 value of 16 693 mg/L.【Conclusion】This study identified the pathogen of P. sylvestris var. mongholica leaf blight as S. polyspora, the optimal carbon source for mycelial growth was glucose, pH 5, light conditions were 24 h continuous, and mycelial lethal temperature was 55 ℃. Among the tested fungicides, 25% myclobutanil, 45% prochloraz, and 10% difenoconazole demonstrated superior inhibitory effects. This study provides a theoretical foundation for developing targeted management strategies and further elucidating the pathogenic mechanisms of S. polyspora.
【Objective】This research aims to investigate the spatiotemporal evolution characteristics of land use dynamics and ecosystem services in the central China river basins, and provide a scientific basis for ecological environment protection and territorial space planning in major grain-producing regions.【Method】Based on land use changes in the upper reaches of the Zhanghe River basin from 2000 to 2020, this study employed models such as InVEST and PLUS to explore the spatiotemporal evolution patterns of land use and ecosystem services under different scenarios in the past and future of the basin.【Result】(1) From 2000 to 2020, the basin experienced rapid cultivated land reduction and continuous construction land expansion. By 2035, under the natural development scenario, construction land expanded rapidly, encroaching on cultivated, grassland, and forest land. However, under cultivated land protection and ecological protection scenarios, construction land expansion was curbed, effectively preserving cultivated and forest land. (2) During 2000-2020, water yield and soil conservation increased, while carbon storage and habitat quality decreased. High-value areas for carbon storage, habitat quality, and soil conservation were found in the basin’s east-central and southeastern forests, whereas low-value areas were in the south-central construction land. Water yield exhibited an opposite spatial pattern, decreasing with increasing topographic gradient. (3) The ecological protection scenario yielded the greatest ecosystem service improvements and is suitable for future development.【Conclusion】The ecological protection scenario offers decision-making support for ecological protection and land development in the basin’s upper reaches. Future efforts should focus on resolving construction land-cultivated land conflicts and optimizing territorial space development strategies to promote land use structure transformation toward high ecosystem service provision.
【Objective】This study aims to explore effective methods for identifying boundaries of urban scenic spots and to provide a scientific basis for their delimitation.【Method】This study used Zhongshan Scenic Spot as a case study. utilizing multi-source data, a comprehensive evaluation model for scenic resource grades was constructed. Spatial kernel density analysis, fractional vegetation cover (FVC), GIS reclassification, and overlay analysis were employed to create a scenic resources evaluation distribution map categorized into five grades by the natural discontinuity classification method: rich, relatively rich, general, relatively scarce, and scarce in scenic resources. The aggregate polygons function in ArcGIS was then used to merge small patches (less than 1 000 m2) into adjacent larger patches and smooth the boundary. Finally, the boundary of Zhongshan Scenic Spot was delineated based on source protection, tourist density, and related planning standards.【Result】The resulting boundary delineation showed that the total area of Zhongshan Scenic Spot was 37.48 km2, with a new area of approximately 2.06 km2 and a reduced area of about 0.49 km2, resulting in an overall increase of about 1.57 km2 compared with the original boundary.【Conclusion】Supported by multi-source data, this method provides a comprehensive evaluation model that considers landscape, ecology, social environment, and urban development, offering high accuracy and objectivity for the protection and sustainable use of scenic resources.
【Objective】The construction of an ecological security pattern in cross-border areas is the key to ensuring regional ecological security and high-quality development. By building an ecological network across regions, this study reveals the degradation and spatial heterogeneity characteristics of ecological barriers in the process of rapid urbanization, promotes the integrity, connectivity and stability among ecological sources, and provides a scientific basis for the protection and optimization of the ecological security pattern of cross-provincial urban agglomerations.【Method】Taking the Nanjing-Hefei metropolitan area as the research area, the spatio-temporal pattern changes of the ecological security pattern in 2000, 2010 and 2020 were compared and analyzed. Based on the reversible nature of ecological sources, the restored and newly added ecological sources were selected to optimize the regional ecological security pattern. Combined with the regional ecological background, the protection and restoration pattern of territorial space was proposed, and the collaborative governance path of the ecological network in the cross-border area was explored.【Result】(1)The number of ecological sources in the study area decreased year by year from 2000 to 2020, while the total area remained stable and increased. (2)The overall habitat quality in the study area was at a medium level from 2000 to 2020 and showed a declining trend, while the ecological resistance gradually increased.(3)The number of ecological corridors increased first and then decreased in the three periods, and the number of ecological nodes increased year by year. The eastern part of the study area was lacking in ecological corridors.(4)The number of high-priority ecological corridors in the study area increased first and then decreased from 2000 to 2020, and the overall spatial distribution pattern was an inverted “T” shape. The ecological network structure became increasingly fragile.(5)Combining the spatial distribution of the natural ecological background of the study area and the optimized ecological security pattern, the protection and restoration pattern of territorial space was proposed as “multiple cores, four corridors, three screens, two belts and one center”, and the construction path of collaborative governance of the ecological environment in the cross-border area was explored.【Conclusion】This study considers the integrity of the ecological network of the Nanjing-Hefei metropolitan area from the perspective of spatiotemporal changes, and optimizes the ecological security pattern based on the actual situation of the regional ecological background. It also proposes measures for the protection and restoration of national land space, which can provide theoretical basis and technical reference for the ecological security and cross regional protection and restoration of national land space in the Nanjing-Hefei metropolitan area.
【Objective】The establishment of the national carbon market represents a significant institutional innovation for reducing greenhouse gas emissions through market mechanisms and promoting green and low-carbon development. It also serves as a crucial policy instrument for advancing the achievement of the carbon-peak goal and the carbon-neutrality vision. The scientific, fair, and reasonable allocation of carbon emission quotas lies at the core of the carbon trading process. This study analyzed the allocation of carbon emission quotas within the carbon trading system based on the current situation and proposed optimization strategies to offer references for the development of China’s carbon trading market.【Method】Adopting the research path of “status quo-problems-countermeasures”, this study employed methods such as literature review, case summarization, and comparative analysis. It analyzed the quota allocation models of major international carbon markets, summarized the current status and main problems of China’s carbon emission quota allocation mechanism, and puts forward relevant suggestions for future mechanism and strategy optimization.【Result】(1) From an international perspective, the practical experiences of major markets in carbon emission quota allocation were summarized. For instance, setting appropriate emission-reduction targets and flexible adjustment mechanisms in the carbon market, building sufficient confidence in participation and a stable price mechanism, as well as establishing a sound and perfect market mechanism and supporting legal system, provided valuable insights and references for the orderly implementation of a combination of free and paid carbon emission quota allocation methods.(2) From a domestic perspective, the current situation of China’s carbon emission quota allocation was summarized. With the development of China’s carbon trading market, certain achievements have been made in carbon emission quota allocation, including the gradual optimization of the tier-by-tier total quota amount, the progressive expansion of the covered industry scope, the diversification of allocation principles, and the gradual transition of the allocation mode from free to paid. Nevertheless, there are still numerous issues to be addressed, such as the need to improve the top-level design, the relative simplicity of the allocation method, the lack of stimulation of market vitality, and the necessity to enhance supporting measures.【Conclusion】Based on the current situation and future development trends of China’s carbon emission quota allocation, it is essential to strengthen the overall planning and top-level design of allocation, promote the progressive development of allocation, establish a scientific and reasonable trading ecosystem, improve laws, regulations, allocation methods, market mechanisms, and other supporting measures, and promote the market-based empowerment and optimization of the carbon emission quota allocation strategy. This will offer solution paths and model references for the development of China’s carbon trading market and the effective realization of carbon-emission-reduction targets.
【Objective】Accurately and efficiently monitoring the spatio-temporal distribution characteristics of the ecological environment quality and its evolving trends in the source area of the Yangtze River is of great significance for maintaining the high-standard protection of the ecological environment. It also serves as a fundamental basis for formulating long-term and effective ecological protection and restoration strategies in the Sanjiangyuan region. The remote sensing ecological index (RSEI) has distinct advantages over traditional evaluation methods relying on single monitoring indices. It boasts rapid assessment capabilities, objectivity, high efficiency, strong visual interpretability, and reliable predictability. Nevertheless, the spatial resolution constraints and the complexity of data acquisition and processing in remote sensing images still present challenges to the large-scale and accurate evaluation of the RSEI.【Method】In this study, the Google Earth Engine (GEE) platform was utilized, with Landsat series images as the data source. Remote sensing images of the Yangtze River source area during the vegetation-growing season (from June to September) from 1990 to 2020 were obtained. Subsequently, long-time-series RSEI data were calculated. To comprehensively analyze the RSEI in the Yangtze River source area from 1990 to 2020, the coefficient of variation was applied to measure its stability, the Sen + Mann-Kendall (Sen + MK) trend analysis was used to explore the spatio-temporal change trends, the Hurst index was employed to predict future evolution, and the trend analysis method was adopted to identify the driving forces behind these changes.【Result】(1) From 1990 to 2020, the RSEI values in the Yangtze River source region were predominantly distributed within the range of 0.4-0.6. Geographically, the region exhibited a clear pattern where the RSEI values were higher in the eastern and southern parts and lower in the western and northern parts.(2) The average coefficient of variation of the RSEI in the source region was 6.52%. This indicates that the ecological environment in the eastern and western regions underwent relatively more pronounced fluctuations, while the central region remained relatively stable. Overall, the RSEI showed a slow oscillating trend, with an average annual growth rate of 0.004 7. Spatially, the RSEI presented an overall upward trend, and the area with improved ecological conditions accounted for 83.63% of the total study area.(3) The average Hurst index value of the RSEI in the source region was 0.53, implying that the future changes of the RSEI were more likely to be continuous rather than show anti-sustainability. The future ecological environment quality in the Yangtze River source region was expected to experience continuous improvement, yet the overall trend was relatively mild, and there still existed an underlying risk of degradation.(4) In the Yangtze River source region, the RSEI was positively correlated with air temperature, night-light index, and potential evapotranspiration. This reveals that both natural factors and human activities had a certain degree of influence on the enhancement of the ecological environment quality.【Conclusion】The integration of using GEE for remote sensing data acquisition and time-series data analysis has significant potential for rapidly and comprehensively monitoring the ecological environment quality on a large scale. This approach can offer valuable references and technical support for ecological monitoring and protection efforts in the Sanjiangyuan area, thereby contributing to the sustainable development of the regional ecological environment.
【Objective】Forecasting future land use changes under different scenarios in Wuxi City and studying the spatial and temporal variations in water yield services and their driving factors are crucial for local ecological and socio-economic sustainability. 【Method】The FLUS and InVEST models were used to predict future land use changes based on historical trends. The spatial and temporal variations in water yield services in Wuxi City from 1990 to 2030 were analyzed, and scenario analysis was employed to identify the main factors influencing water yield.【Result】The primary historical land use change in Wuxi had been the conversion of cultivated land to developed land. During the study period, the area of cultivated land decreased by 32.69%, while developed land increased by 217.25%. The historical annual average water yield in Wuxi was 2.552 × 109 m3, with a depth of 612.34 mm. Water yield varied with rainfall and evapotranspiration, initially decreasing and then increasing. Spatially,the high-value areas of water production were concentrated in the southwestern forest and northeastern grassland areas, while the low value areas were concentrated in the central water area. During the four time periods of 1990 to 2000, 1990 to 2010, 1990 to 2020, and 2020 to 2030, the changes in water yield were influenced by land use transfer and changes in precipitation. These two factors contributed to the water yield of the four time periods by -10.00% and 110.00%, 12.50% and 87.50%, 1.00% and 99.00%, 5.46% and 94.54%, respectively. Precipitation is the main factor affecting changes in water yield. 【Conclusion】Scenario analysis results indicate that changes in rainfall have a more significant impact on water yield than changes in land use. Rainfall is the primary driver of variations in water yield, providing a scientific basis for water allocation in the study area.
【Objective】This study aimed to identify the types, distribution, quantity, and sexual dimorphism of antennal sensilla in Xanthogaleruca aenescens through ultrastructural observation. The findings provide a basis for understanding the genetic evolution, morphological classification, and the role of olfactory sensilla in host volatile detection in leaf beetles.【Method】The antennae of adult female and male X. aenescens were cleaned, air-dried, and gold-coated for scanning electron microscopy (SEM). SEM was used to observe and photograph the morphological characteristics of the antennae and sensilla of both sexes, as well as to identify the types of sensilla present. Independent sample t-tests were conducted to compare differences in antennal length, sensilla length, base diameter, and the number of sensilla between the sexes, and the distribution of sensilla across the antennae was also examined.【Result】The antennae of X. aenescens were linear and consist of the scape, pedicel, and nine flagellar subsegments. The average length of male antennae was (4 558.01 ± 104.15) μm, while that of females was (4 488.75 ± 224.33) μm. Males have slightly longer antennae than females, although this difference was not statistically significant. Both males and females possessed eight types of antennal sensilla: sensilla trichodea (St), sensilla chaetica (Sc), sensilla basiconica (Sb), sensilla styloconica (Sst), Böhm bristles (Bb), sensilla gemmiformium (Sg), sensilla coeloconica (Sco), and sensilla auricillica (Sau). St and Sb each have four subtypes, Sc has two subtypes, and Sst has three subtypes. The female antennal flagellum has Sst 2, while the male flagellum contains Sst 3. The most abundant sensilla are St, followed by Sb, while Sco is the least common. St 4, Sb 1, Sb 3, and Sau exhibit micropores on their surfaces, indicating their role as olfactory sensilla. The total number of antennal sensilla in females was significantly greater than in males (P < 0.01). Specifically, the numbers of St 2, Sb 2, and Sst 1 were significantly higher in females (P < 0.05). St 4 and Sb 3 is significantly higher in females than in males (P < 0.01), while Sau was significantly fewer in females compared to males (P < 0.01). No significant differences were observed in the number of other sensilla. In both sexes, the tips of antennal subsegments F2 to F8 had inwardly concave areas with a high density of sensilla, and a similar concave area was present at the middle of the terminal segment F9. The density and number of sensilla increased from the base to the tip of the antenna. Additionally, the ventral surface of the male antennal flagellum (F1 to F8) exhibited a more densely packed area of epidermal depressions, a feature absent in females.【Conclusion】Both female and male X. aenescens have the same types of antennal sensilla, but there are clear sexual dimorphisms in sensilla subtypes, quantity, and distribution. Different subtypes of Sst were observed in males and females, with variations in the size of sensilla between the sexes. The total number of sensilla in males was significantly lower than in females. The specific roles of these sensilla in environmental perception, host detection, and mating behaviors should be further explored using transmission electron microscopy, electrophysiology, and other advanced techniques.
【Objective】This study investigated the effects of arbuscular mycorrhizal fungi (AMF) colonization on the growth and photosynthetic characteristics of Leucojum aestivum. 【Method】Two-year-old bulbils of L. aestivum were selected as the experimental material. The experimental design consisted of five groups, three of which received single AMF inoculations [inoculated with Rhizophagus intraradices (Ri), Funneliformis mosseae (Fm), and Diversispora tortuosa (Dt)]. The fourth group was inoculated with a 1∶1∶1 mixture of the three AMF species (Mi), and the control group was inoculated with a sterilized 1∶1∶1 mixture of the AMFs. After two months, plant height, fresh and dry weight, and photosynthetic characteristics of L. aestivum were measured. 【Result】The Fm group exhibited the highest infection rate at 69.38%, while the Ri group had the lowest infection rate at 36.93%. The infection rate in the Ri group was significantly lower than those of the Fm, Dt, and Mi groups. Among the treatment groups, the Fm group showed the most plant height (43.46 cm) and the dry weight (39.94 g). Photosynthetic parameters indicated that the Ri group had the most average stomatal conductance [Gs = 0.30 mol/(m2·s), intercellular CO2 concentration (Ci = 331 μmol/mol), and transpiration rate (Tr = 3.45 mmol/(m2·s), with the transpiration rate significantly higher than in the control group (CK)]. Correlation analysis revealed a generally significant positive correlation between net photosynthetic rate (Pn) and Gs across all treatments, except for leaf stomatal conductance (Ls) and Ci. Although other photosynthetic indices exhibited correlations, no consistent pattern was observed across treatments. Membership function analysis indicated that the inoculation effect of the Mi group was the most beneficial, followed by Dt. 【Conclusion】AMF colonization effectively promotes the growth of L. aestivum. The effects on photosynthesis vary across different AMF species, with Dt and Mi significantly enhancing the photosynthetic capacity and biomass of L. aestivum. In contrast, Fm positively affected plant height but did not significantly influence photosynthetic capacity.
【Objective】The study aimed to determine the effects of a biocontrol agent used to treat zelkova (Zelkova schneideriana) wilt disease caused by Fusarium oxysporum on the microorganisms in the rhizospheric soil of zelkova. 【Method】The disease control efficiency and growth promoting effects of Bacillus velezensis HZM9 on zelkova trees challenged by F. oxysporum in a plantation in Jurong City, Jiangsu Province, were determined in this study. The diameter at breast height (DBH) and death rate of the zelkova trees were analyzed after one year of treatment. Samples of rhizospheric soil were collected from the region around the roots of zelkova trees, following which the activities of four enzymes (soil urease, alkaline phosphatase, catalase, and sucrase) and the structure of the microbial community in the soil were analyzed. 【Result】Compared to that of the untreated control, B. velezensis HZM9 treatment increased the DBH of zelkova trees by 17%, and reduced their death rate from 8.7% to 5.3%. Treatment with B. velezensis HZM9 had little influence on the activities of soil enzymes but increased the soil microbial diversity. In particular, the relative abundance of the beneficial microbial groups, including Mortierella sp., improved significantly. 【Conclusion】The findings indicated that B. velezensis HZM9 can significantly promote the growth of zelkova trees and alter the structure of the soil microbial community, which may benefit the long-term production of zelkova trees.
【Objective】Agroforestry compound management is widely acknowledged as a promising strategy for guaranteeing the sustainability of future agricultural production. This research is dedicated to exploring and optimizing the agroforestry management system with Chinese characteristics. By elucidating its complex mechanisms and summarizing empirical models, the study aims to maintain the sustainable production of both forestry and agriculture in the future. 【Method】Based on an all-round review of agroforestry management practices, this paper focuses on constructing the agroforestry management mechanism to identify the roles of various factors. It also aims to summarize experience-based models suitable for different environmental conditions. Specifically, a detailed analysis of biophysical factors, socio-economic factors, farmers’ endowments, production enterprises, and safeguard measures has been carried out. 【Result】(1) The agroforestry management mechanism is significantly influenced by multiple factors. These encompass biophysical conditions such as soil quality, climate, and topography; socio-economic factors like market demand, economic policies, and the rural labor force; farmers’ endowments in terms of land resources, farming skills, and financial capabilities; production enterprises with their production scale, technological innovation, and market-orientation; and safeguard measures including agricultural policies, forest protection regulations, and rural infrastructure construction. (2) According to the degree of utilization of ecosystem types, agroforestry management systems can be classified into four main categories: agroforestry systems, mainly centering on the combination of agricultural crops and forest trees; forest-pastoral systems, emphasizing the integration of forestry and livestock grazing; agroforestry-pastoral systems, integrating agriculture, forestry, and animal husbandry; and other special systems customized to specific local ecological and socio-economic conditions. (3) In Europe and the Americas, through the efforts of farms and research institutes, forest-farm-livestock composite management practice systems and scientific research systems have been established respectively. These systems enable the meticulous management of agricultural production, covering aspects such as precise resource allocation, scientific breeding, and the efficient utilization of agricultural land. In contrast, most regions in Asia still primarily rely on traditional agroforestry management systems, which are characterized by relatively simple production models and less advanced technologies. (4) China has a long-standing history of agroforestry management with diverse modes. These modes show obvious spatial differentiation due to differences in the natural environment, economic development level, and cultural traditions in different regions. However, there is still a gap between the technological application in China’s agroforestry management and the international advanced level, especially in areas such as modern agricultural machinery, information technology, and ecological management. 【Conclusion】In light of the above-mentioned findings, it is of great significance to promote the sustainable development of China’s agroforestry management system. This can be achieved by establishing an agroforestry management mechanism tailored to local conditions, actively enhancing farmers’ production concepts and technical capabilities through training and extension services, and constructing a comprehensive risk-defense mechanism and a sound policy-guarantee system. The risk-defense mechanism should cover aspects such as natural disaster prevention, market risk mitigation, and technological innovation risks, while the policy-guarantee system should include preferential policies for agroforestry development, financial support, and land-use policies.
【Objective】This study aims to investigate the production efficiency of carbon sequestration forestry and identify its key influencing factors. This exploration serves as a crucial foundation for the high-quality development of forestry in China. It not only provides essential insights for formulating differentiated forestry development policies but also facilitates the optimal allocation of forestry resources and promotes coordinated and balanced regional development across the country.【Method】The economic value and efficiency levels of carbon sequestration forestry in 31 provinces of China from 2003 to 2018 were evaluated using the volume expansion method, SBM model, Dagum Gini coefficient, and Tobit model. Building on this analysis, the study delved into the dynamic changes in comprehensive efficiency, pure technical efficiency, and scale efficiency, as well as their spatiotemporal differentiation. Additionally, the key influencing factors were systematically explored.【Result】The findings revealed that China’s forestry carbon sequestration storage level was relatively high, with Xizang, Sichuan, and Yunnan being the top three provincial area in terms of forestry carbon sequestration economic value. Comprehensive efficiency, pure technical efficiency, and scale efficiency exhibited significant regional disparities and demonstrated distinct spatial agglomeration characteristics. Both inter-regional and intra-regional differences were identified as the primary sources of regional variations in the production efficiency of carbon sequestration forestry in China. The proportion of forestry output value and investment in forestry human capital were found to positively influence the production efficiency of China’s carbon sequestration forestry, whereas per capita GDP and the incidence of forest diseases, pests, and rodents exerted a restraining effect.【Conclusion】China’s forestry development can achieve high-quality growth in carbon sequestration forestry by enhancing the efficient utilization of forestry resources, reducing regional efficiency disparities, and addressing key influencing factors. This approach will contribute to the sustainable and balanced advancement of the forestry sector.
【Objective】This study aims to investigate the vertical and short-range horizontal spatial distribution patterns of leaf area index (LAI) in broadleaved-Korean pine forests and explore the application value of the stratified Voronoi diagram method in simulating the spatial distribution of LAI in multi-storey forest ecosystems.【Method】The study focused on the virgin broadleaved-Korean pine forest located on the downhill side of the core zone of Liangshui National Nature Reserve. The trees within the forest stand that reached the minimum diameter at breast height (5 cm) were divided into five height classes (Class Ⅰ, H < 10 m; Class Ⅱ, 10 m ≤ H < 15 m; Class Ⅲ, 15 m ≤ H < 20 m; Class Ⅳ, 20 m ≤ H < 25 m; Class Ⅴ, H ≥ 25 m).The Voronoi diagram method was used to simulate the spatial distribution of LAI in different height classes within the forest. The results were combined to form an overall spatial distribution of LAI for the forest stand. Furthermore, the overall characteristics of LAI at the forest stand scale were analyzed, including the vertical distribution patterns of LAI for different tree species and the entire forest stand. The short-range horizontal spatial autocorrelation patterns of LAI at different height classes and the overall forest stand were analyzed using the spatial semivariance function and incremental spatial autocorrelation method. 【Result】Three results were obtained. First, the overall LAI of the study plot was 10.807, with Pinus koraiensis, Acer momo, Betula platyphylla, Tilia amurensis and Fraxinus mandshurica making the top five contributions to the stand LAI. The local LAI in the understorey varied within the range of 0-75, with 48.7% of the understorey having a LAI of 0. The probability density histogram of the LAI in the area with canopy cover had a single-peak distribution, with the peak between 15-25. Second, the LAI of broadleaved-Korean pine forest was 0.420, 2.420, 2.210, 2.707 and 3.050 from height class I to height class V respectively, with vertical distribution tendency degree of total LAI in the stand being 1.171 and the coefficient of variation of total LAI in different height classes being 47.3%. From height class Ⅰ to Ⅴ, the number of canopy patches was 53, 39, 12, 11, and 8 respectively. The LAI under the canopy patches of each species showed an increasing trend as the height level increased. Third, the Nugget value, Sill value, range and Nugget/Sill ratio of the spatial semi-variance function of LAI in broadleaved Korean pine forest were 4.770, 164.010, 5.108 m and 0.029, respectively. The LAI was similarly clustered at lag distances less than 27.0 m and greater than 38.5 m, and spatially random at lag distances between 27 m and 38.5 m (P<0.05). As the lag distance gradually increased, the Z-score of the LAI showed two peaks at 14 and 24 m.【Conclusion】The LAI of broadleaved-Korean pine forests in gentle slope positions exhibits distinct vertical stratification. The leaf area of different tree species tends to be distributed at different heights. For instance, Pinus koraiensis, Picea asperata, and Fraxinus mandshurica, as tall arbor species, have their leaf area concentrated in the upper canopy. On the other hand, Acer opalus and Ulmus, representing middle-sized and small-sized arbor species, have their leaf area concentrated in the lower canopy. The LAI of broadleaved-Korean pine forests in lower gentle slope positions exhibits strong short-range spatial autocorrelation in the horizontal direction. The horizontal spatial distribution of LAI within the forest stand was similarly clustered at most research scales, which is strongly influenced by the spatial distribution of trees.
Vegetation effectively removes airborne particulate matter through “direct” and “indirect” pathways, each with distinct mechanisms and processes. Osmanthus fragrans, one of the top ten traditional flowers in China, is widely distributed in south of the Qinling Mountains across the subtropical regions. Research results indicate that this species plays a significant role in mitigating atmospheric particulate pollution and improving air quality by retaining particulate matter. We analyzed and summarized advancements in understanding the dust retention capacity of O. fragrans, emphasizing key quantitative indicators such as dust retention per unit leaf area, per single leaf, and the ability to retain particulates of various sizes. This study also explored spatiotemporal variations in dust retention and its impact on spectral characteristics, morphological structure, and physiological ecology. Differences in dust retention among O. fragrans varieties and habitats were attributed to genetic traits and environmental factors, including air pollution levels, leaf morphology, leaf area, phyllotaxy, inclination angle and crown shape. Key findings include the following:(1) Correlation with environmental pollution. Dust retention per unit leaf area was positively correlated with the background level of air pollution. (2) Influence of morphological traits: dust retention per single leaf was determined by leaf morphology and environmental conditions, though no significant correlation was found between single-leaf area and particulate retention capacity. (3) Plant-level variation. Total dust retention varied significantly among plants due to differences in leaf area across growth stages, health conditions, and locations. (4) Particulate size specificity. Leaves retained coarse particulates more effectively than fine ones, and dust retention showed predictable spatiotemporal variation. Diurnal and seasonal trends aligned with fluctuations in airborne particulate matter, with species- and region-specific saturation times. (5) Impact on leaf traits. Particulate retention altered leaf spectral characteristics, affecting morphology, functional traits, and adsorption capacity. These changes influenced physiological ecology, growth, floral fragrance, and ornamental value.
【Objective】Parasitic nematodes are invertebrates that infest pine trees, feeding on plant cells and potentially harming tree health. Some nematodes can even kill pines (Pinus spp.). In 2022, a new parasitic nematode was isolated from black pine (Pinus thunbergii) and tentatively named the Liaoning nematode. To clarify its taxonomic status, both morphological and molecular biological identifications were performed to determine its species and guide its prevention and control.【Method】The Baermann funnel method was employed to separate nematodes from dead wood samples. After three washes with sterile water, the nematodes were transferred to Botrytis cinerea for seven days. Morphological characteristics of female and male adult nematodes were observed and measured using light microscopy. For molecular identification, DNA was amplified and sequenced using 18S rDNA, 28S rDNA, and COI gene primers to construct an evolutionary tree and further assess the taxonomic status.【Result】The primary morphological features of the Liaoning nematode are as follows: The average body length of female adults is 580.6 μm, mean body width is 17.3 μm. Female adults are slightly ventrally curved when heat-relaxed, with fine annules between the lip and body and a stylet with small basal swellings. The median bulb is ovoid, with a height and width of 11.8 and 8.4 μm, respectively. The vulva, without a vulval flap, is inclined at 45° and located between 60%-70% of the body length, with a distance from the posterior vaginal sac of 25.6 μm. The average distance between the vagina and anus is 131.9 μm. The tail measures 33.1 μm in length and has terminal shapes resembling snail feelers. The male nematode’s anterior region is similar to the female’s but forms a “J” shape when heat-relaxed and has a shorter body length, approximately 479.2 μm. The stylet length is 10.1 μm, and the body width is about 19.0 μm wider than that of female adults. The spicule length is 14.8 μm, with well-developed condylus and rostrum positioned in the middle and upper part of the spicules. The tail length is 28.0 μm, with short protrusions at the terminal. These morphological features align with A. paradanlianensis. DNA cloning and sequencing of the 18S rDNA, 28S rDNA, and COI genes produced target fragments of 914, 769 and 687 bp, respectively. BLAST alignment on NCBI revealed the highest similarity to A. paradanlianensis. Phylogenetic analysis indicated that the Liaoning nematode and A. paradanlianensis are closely related, confirming the nematode’s taxonomic status.【Conclusion】 Combining morphological and molecular characteristics, the Liaoning nematode isolated from P. thunbergii has been identified as A. paradanlianensis, marking its first discovery on pine trees in China. While morphological measurements of the Chinese population are slightly higher than those of the Korean population, the characteristics are generally consistent, possibly due to geographic variations or intra-species differences.
【Objective】This study aims to raise public awareness about the risks associated with underground parking garages in Nanjing City by analyzing heavy metals in surface dust and evaluating both ecological and human health risks. 【Method】Surface dust samples were collected from underground parking garages in different regions of Nanjing for heavy metal analysis. Source apportionment analysis was performed using the absolute principal component scores-multiple linear regression (APCS-MLR) receptor model. Ecological risk was assessed using the geo-accumulation index method and the potential ecological risk index method. Human health risks were evaluated using the human health risk index. 【Result】(1) Four sources of heavy metals in surface dust were identified: fuel combustion, industrial emissions, road and industrial dust deposition, and vehicle exhaust emissions. (2) In the study area, average geo-accumulation index values for Zn and Cu indicated moderate to strong pollution, while the potential ecological risk index suggested a relatively high ecological risk. (3) For human health, cumulative non-carcinogenic risks for the six heavy metals exceeded the safe threshold for children (>1) but remained within a manageable range for adults (<1). Carcinogenic risks associated with Ni and Cr exceeded acceptable levels, with value standards (1×10-4). 【Conclusion】The presence of heavy metals in surface dust from underground parking garages in Nanjing negatively impacts both the ecosystem and human health, underscoring the need for preventive and control measures.
【Objective】The critical challenges in ecological health assessment involve establishing a comprehensive assessment system and selecting appropriate indicators. This study aims to evaluate the ecological health status of nature reserves to provide a scientific basis for improving the regional ecological environment. 【Method】This study established a comprehensive ecological health evaluation index system for the Sichuan Liziping National Nature Reserve. The system encompasses five criteria: natural resource characteristics, river ecological resources, social value, service management system, and ecological environment conditions, further subdivided into 31 specific indicators. A fuzzy analytic hierarchy process (AHP) model was employed to evaluate the reserve’s ecological health. 【Result】The evaluation revealed the relative weights of the criteria as follows: natural resource characteristics (0.157), river ecological resources (0.277), social value (0.124), service management system (0.073), and ecological environment conditions (0.370). The maximum eigenvalue and consistency index were calculated as 5.158 and 0.040. Membership scores for natural resources, social value, and ecological environment conditions in “healthy” and “sub-healthy” states were 0.687 and 0.218, 0.504 and 0.373, 0.608 and 0.212, respectively. River ecological resources showed membership scores of 0.509 in “high quality” and 0.275 in “sub-healthy” states, while the service management system exhibited a “healthy” state membership score of 0.394. Overall, the ecological health evaluation yielded scores for “high quality” (0.232), “healthy” (0.452), “sub-healthy” (0.255), “unhealthy” (0.061), and “sick” (0) membership states. The comprehensive membership score was 0.452, categorizing the reserve’s ecological health as “healthy.” 【Conclusion】 This study offers a scientific foundation and technical guidance for ecological conservation and the integrated management of the ecological environment in the Liziping National Nature Reserve.
【Objective】This study addresses the construction of scenic trails, aligning with the trend of resource integration in abundant region of nature reserves and the growth of global tourism. It begins with the recreational resources of abundant region of nature reserves and puts forward a comprehensive set of methods for selecting and planning recreational scenic trails from a regional perspective. This is intended to fill gaps in existing theoretical research on scenic trails at both the resource and regional levels within nature reserves. 【Method】Utilizing the analytic hierarchy process (AHP) and ArcGIS spatial analysis, potential scenic roads were preliminarily screened. Combined with the natural and human geographical characteristics of the study area, comprehensive evaluations of potential scenic roads were conducted. Key features of these roads were then summarized using visual field sections. 【Result】GIS spatial analysis yielded evaluations of each potential scenic road. After considering the current conditions and conducting overlay analysis, 23 potential scenic roads were identified. The comprehensive assessment of factors influencing route selection revealed 10 optimal scenic roads, including G205, G235, S222, among others. Furthermore, recreational scenic roads in southwestern Zhejiang were classified into three levels, with the distinct characteristics of each level described intuitively. 【Conclusion】The recreational scenic roads in the southwest of Zhejiang Province are meticulously planned according to a “2+6+7+N” construction pattern. This involves two national parks serving as core areas, six primary scenic roads functioning as communication corridors, and seven ecological recreation areas being interconnected in a series. Additionally, numerous branch corridors are prominently displayed. Concurrently, a visual area section analysis of these main recreational scenic roads has been designed, offering a theoretical foundation and data support for the scientific selection of scenic road routes in southwest Zhejiang.
【Objective】Soil faunas are crucial components of forest ecosystem. This study investigated the distribution characteristics and seasonal variation of soil macrofauna in Metasequoia glyptostroboides plantations of different ages. We analyzed differences in the community structure, seasonal dynamics, and influencing mechanisms of surface soil macrofauna, providing a theoretical basis for future studies on soil fauna community structure in these plantations.【Method】We assessed soil macrofauna community dynamics across nine M. glyptostroboides plantations (seven, 11, 16, 21, 26, 31, 36, 41, and 46 years old) using a randomized block design with four replicate plots per age group, located in a coastal area of northern Jiangsu Province, China. Collections were made in summer (August) and autumn (October) using pitfall traps, and samples were sorted and identified under a stereomicroscope in the laboratory. Additionally, soil samples from the 0-15 cm layer were collected for physicochemical analysis.【Result】We collected a total of 14 289 surface soil macrofauna individuals from 16 orders and 23 families. The dominant groups were Armadillidae and Oniscidae. Significant differences were observed in the dominant and common groups of soil macrofauna among plantations of different ages. The 11-year-old plantation had the highest number of soil macrofauna, while the 36-year-old plantation had the lowest. In terms of seasonal variation, the total number of surface soil macrofauna was higher in August than in November, whereas species richness was greater in November than in August.【Conclusion】The study highlights that both stand development and seasonal variation significantly influence the community structure of surface soil macrofauna in M. glyptostroboides plantations. As the forest matures, the total number, species diversity and diversity index of surface soil macrofauna increase, reaching a high level in middle-aged forests.
【Objective】This study explored the patterns and environmental factors that drived β diversity and its components in plant communities on the northern slope of Changbai Mountain, to provide a theoretical basis for biodiversity conservation and ecosystem management in the area.【Method】The betapart package of R was used to decompose the components (turnover and nestedness) of β diversity. The generalized dissimilarity modelling (GDM) was used to explore the environmental factors that drived β diversity and its components.【Result】Decomposition of the β diversity components revealed that the β diversity of the plant communities was dominated by the turnover, indicating that species replacement leads to differences in species composition among communities. The results of GDM analysis showed that 13 environmental variables explained 32.63%-66.52% of the β diversity and the turnover components of the plant communities. The mean annual air temperature significantly influenced the arbor β diversity. The arbor β diversity was significantly affected by the annual precipitation and soil bulk density when they reached values higher than 710.00 mm and 1.07 g/cm3, respectively. The turnover components of arbor β diversity were primarily affected by the mean annual air temperature, soil bulk density, and slope. The turnover rate increased with an increase in the values of the predictive variables once the threshold was surpassed. The growth rate of shrub β diversity and its turnover components exhibited a downward, constant and upward trend, respectively, for shrub plants following an increase in air temperature seasonality, slope and mean annual air temperature. However, in response to the major determinants, the gradient changes in the β diversity of herbs and its turnover components increased with altitude, decreased with rising isothermality, and initially increased and then decreased following an increase in soil organic carbon.【Conclusion】Altogether, the findings revealed a turnover pattern in the species composition of plant communities in the northern slope of Changbai Mountain, indicating that biodiversity conservation efforts should focus on multiple species and at multiple regions. The β diversity patterns are primarily affected by environmental factors. The arbor β diversity and its turnover components are primarily affected by the mean annual air temperature, while those of shrub plants are mainly affected by seasonal variations in air temperature, and those of herbs are primarily limited by the altitude.
【Objective】To clone the glutathione S-transferases (GST) genes of Monochamus alternatus (Coleoptera: Cerambycidae) and to determine the expression levels of these genes under heat stress in adult males and females, as well as at different developmental stages of M. alternatus, we used molecular biology and bioinformatics methods. 【Method】 Three GST cDNA sequences were cloned, and their structural characteristics were analyzed using DNAMAN 9.0 and I-TASSER software. qRT-PCR was employed to measure the relative expression levels of GST genes in adult and fourth instar larvae of M. alternatus under varying temperatures and treatment durations. The role of these GST genes in protecting the organism from oxidative stress was assessed through disc diffusion assays. 【Result】Three GST cDNA sequences were cloned and named MaltGSTe1, MaltGSTe2, and MaltGSTt1. MaltGSTe1 and MaltGSTe2 belong to the Epsilon family, while MaltGSTt1 belongs to the Theta family. Analysis of three-dimensional protein structures indicated that these GST are cytoplasmic. The relative expression levels of MaltGSTe1, MaltGSTe2 and MaltGSTt1 in fourth instar larvae significantly changed under heat stress, with MaltGSTe2 showing the greatest change. In males, the expression level of MaltGSTt1 was significantly down-regulated. Escherichia coli expressing the GST genes demonstrated enhanced antioxidant capacity, with MaltGSTe2 exhibiting the strongest activity. 【Conclusion】We successfully cloned three GST genes and investigated their expression characteristics under high temperature stress in M. alternatus. High temperature stress was found to induce up-regulation of GST gene expression. Disc diffusion assays confirmed that heterogeneously expressed GST proteins have antioxidant capabilities. These findings suggest that GST genes play a role in the response mechanism to high temperature stress by protecting against oxidative stress, providing a theoretical foundation for exploring the heat resistance mechanisms of M. alternatus in subtropical regions.
【Objective】Pinus massoniana, a predominant tree species in Chinese forests, is highly susceptible to pine wood nematode (PWN), Bursaphelenchus xylophilus, which causes pine wilt disease and can lead to severe economic and ecological damage. This study aimed to develop an evaluation system for assessing the resistance of P. massoniana embryogenic callus to PWN and to screen for cell lines that exhibit enhanced resistance.【Method】The embryogenic callus induced from immature embryos of P. massoniana, sourced from Guangyun Forest Farm in Pingle County, Guilin City, Guangxi Zhuang Autonomous Region, China, was used as the experimental material, and the embryogenic callus of P. thunbergii and P. elliottii was used as the control group. The strongly virulent PWN strain AMA3c28, maintained at Nanjing Forestry University, China, was utilized for inoculation. Bacterial-free PWNs were obtained by sterilizing nematode eggs with 15% H2O2 for 50 min followed by rinsing in sterile water three times. The sterilized eggs were then inoculated onto pine callus, where they hatched and proliferated. The bacterial-free PWNs were collected and each callus piece from different cell lines was inoculated with 50 μL of a nematode suspension containing approximately 500 nematodes. Control groups were inoculated with an equal amount of sterile water. Post-inoculation, the cultures were incubated at 25 ℃ in the dark, and morphological changes were observed after 10 d, followed by the microscopic examination of cellular morphology. The cell viability was assessed using the 2,3,5-triphenyltetrazolium chloride (TTC) staining method. The population dynamics of PWN within the callus were evaluated by re-isolating the nematodes using the Baermann funnel technique. 【Result】The study revealed a marked variation in PWN resistance among the P. massoniana cell lines. The cell lines GX19-1-2 and GX20-3-3 exhibited the highest resistance and minimal morphological changes, maintaining an cell structural integrity after inoculation with bacterial-free PWNs for 10 days. In contrast, cell lines GX20-4-4, GX20-1-10, GX20-3-5, GX20-1-1 and GX20-1-7 exhibited severe browning, tortured cell structure, and significant growth inhibition, indicating weaker resistance. TTC staining confirmed these observations, with resistant cell lines showing vibrant red staining similar to the control groups, while susceptible lines turned pink and white, indicating reduced cell viability. Microscopic examination of cell structures post-inoculation further validated the resistance profiles, with resistant lines maintaining clear embryonic head-stem structures, and susceptible lines showing disrupted cellular integrity and a leakage of cellular contents. The population dynamics of PWN within the callus varied significantly among cell lines. Notably, the P. thunbergii cell line 36-2 exhibited the highest reproduction of PWN (107 333 ± 9 333), indicating a high susceptibility. In contrast, the P. massoniana cell lines GX19-1-2 and GX20-3-3 showed lower PWN levels, which were significantly lower than that of the two P. elliottii cell lines 1907-9 and 1927-1, suggesting a strong inhibitory effect on nematode reproduction and strong resistance. Cell line GX20-3-8 had similar resistance compared to that of P. elliotti cell lines. 【Conclusion】This study successfully developed an in vitro evaluation system for assessing the resistance of P. massoniana to PWN, revealing that cell lines GX19-1-2 and GX20-3-3 exhibit promising levels of resistance. The results act as a basis for future research, contribute to the development of resistant P. massoniana varieties, and can be employed to establish a new research platform for enhancing our understanding of the interactions between host pine trees and the PWN.
【Objective】The somatic embryogenesis induction system of resistant Pinus elliottii is established and optimized to provide technical support for the large-scale rapid propagation of high-resistant materials of P. elliottii. 【Method】 The immature zygotic embryos from four families of P. elliottii are used to explore the effects of different families on the embryogenic callus initiation rate. The embryogenic callus with good proliferation rate and generating large quantity of embryo suspensor mass is selected to test somatic embryo maturation. The maturation conditions of somatic embryos are optimized based on genotype, phytosulfokine (PSK) concentration, and subculture times. 【Result】A significant difference is observed in the initiation frequencies of embryogenic callus among the four families (P < 0.05). Family No. 30 has the highest initiation rate (29.8 ± 5.6)%, while family No. 32 has the lowest (7.3 ± 3.4)%. A total of 37 embryogenic cell lines with stable proliferation are obtained. Of these, 25.7% of 35 cell lines produce matured somatic embryos, and the yields (number of somatic embryos) in 2007-3 and 2007-5 are significantly higher than that of other cell lines, with an average yield of (91.3 ± 7.0) and (89.8 ± 8.4) cotyledonary somatic embryos per mL, respectively, while the remaining 74.3% does not produce any somatic embryos. The addition of PSK significantly affects the yield of somatic embryos of resistant P. elliottii, and embryo production is considerably increased when the PSK concentration is 1 mg/L. The number of mature somatic embryos decreases with the increase in subcultures. The number of mature somatic embryos of cell lines 2007-3 gradually decreases after eight subcultures but maintains embryogenic competence in the 20th subculture. For cell lines 2007-5, the number of mature somatic embryos reduces as subcultures rise, ultimately losing maturation capacity after 20 subcultures. 【Conclusion】The initiation of embryogenic callus is greatly influenced by the genotype. Genotype and PSK concentration significantly affect the somatic embryo yield of resistant P. elliottii. The yield of somatic embryos decreases with the increase in subcultures. The somatic embryogenesis technology system of resistant P. elliottii is optimized to provide technical support for the somatic embryogenesis of excellent genotypes of P. elliottii.
【Objective】This study explored the composition and diversity of plant communities at different succession stages of Platycladus orientalis in typical limestone mountainous areas of Xuzhou City, and revealed changes in species substitution and community structure.【Method】The community characteristics and influencing factors of P. orientalis in four different succession stages: shrub grassland, coniferous forest, coniferous-broadleaf mixed forest, and broadleaf forest were analyzed using a space-for-time substitution method and typical sample plot surveys. 【Result】 (1) A total of 105 plant species across the sample plots, representing 58 families and 96 genera. Species diversity across succession stages included: 14 families, 18 genera, and 20 species in shrub grasslands; 33 families, 49 genera, and 51 species in coniferous forests; 43 families, 59 genera, and 64 species in coniferous-broadleaf mixed forests; and 27 families, 44 genera, and 45 species in broadleaf forests. (2) Regarding importance values of plant species in different succession stages, P. orientalis consistently ranked first in the tree layer, while Broussonetia papyrifera ranked first in the shrub layer, showing a pattern of initial decline followed by an increase. In the herbaceous layer, the species with the highest importance values across the four succession stages were Aristolochia debilis, Rubus parvifolius, Solanum lyratum, and Hedera nepalensis. (3) The Shannon-Wiener diversity index, Margalef richness index, Pielou evenness index, and Simpson dominance index of community followed a similar trend, initially increasing and then decreasing as succession progressed. The diversity index peaked in the coniferous-broadleaf mixed forest stage. (4) The correlation analysis between plant diversity indices and environmental factors indicated that species diversity changes during the succession of P. orientalis forests in Xuzhou’s limestone mountains were significantly correlated with canopy density, slope position, and slope aspect, with canopy density having the greatest influence on the Shannon-Wiener diversity index (P< 0.05). 【Conclusion】 The plant diversity in P. orientalis forests in Xuzhou’s limestone mountainous area peaked during the coniferous-broadleaf mixed forest stage. The study identified canopy closure, slope position, and slope orientation as key factors influencing plant diversity. These findings provide theoretical bases for the transformation and management of near-natural forest stands in the region.
【Objective】Identifying the multifunctional status and hierarchical structure of national nature reserves in Yunnan Province can clarify their functional effectiveness and optimization paths while also providing ideas for establishing the spatial layout and cluster management of the nature reserve system, with national parks as the primary focus.【Method】Based on the functional evaluation system constructed using the pressure-state-response model, which considered the 20 national nature reserves distributed in Yunnan Province as subjects. The entropy value method was utilized to classify the functional levels. At the same time, the order-size law and the coupling coordination degree model were applied to analyze the structure of the functional levels and summarized the types of functional structures. 【Result】The national nature reserves in Yunnan Province exhibited inconsistent progress in their current roles, necessitating a coordinated evolution of these functions. The Zipf index indicated that the functions of Yunnan Province's national nature reserves align with the principle of positional order scale, characterized by uniform development. However, the functional items did not reach a definitive edge, highlighting the need to create beneficial functional items within a single protected area. The national nature reserves in Yunnan Province demonstrated a more intense coupling, significant state dysfunction, and a singular protected area’s coupling strength function. The extent of coordination among these variations could be categorized into generally developed, generally lagging, and severely lagging types. 【Conclusion】A primary reason for the heterogeneity in the functional structure of the study area is the interplay between ecological context and economic and social conditions. Future work should focus on enhancing the dynamic nature reserve monitoring network at the provincial level, which aligns with the principle of “synthesis and special characteristics”. Better-developed national nature reserves should be utilized as a central point to merge and optimize the construction of national parks by modernizing adjacent nature reserves. This approach aims to foster the orderly development of nature reserve functions in Yunnan Province and facilitate the synergistic building of nature reserves.
【Objective】 In order to clarify the coupling coordination relationship between the ecosystem services provision level and well-being level of residents, along with its key influencing factors in ecological resource-rich, former concentrate contiguous special hardship areas, a scientific basis is provided for these areas to formulate development plans and policies aimed at realizing common prosperity based on ecological resources. 【Method】 An evaluation index system for residents’ well-being level was constructed by focusing on the former concentrated contiguous special hardship areas in the Luoxiao Mountain area as the research subject. The ecosystem services provision level was determined using the InVEST model, and the coupling coordination relationship between the ecosystem services provision level and residents’ well-being level, as well as its influencing factors during the period from 2000 to 2020 in the Luoxiao Mountain area, was analyzed utilizing the coupling coordination degree model and econometric regression model. 【Result】 (1) The water conservation, soil conservation, and carbon sequestration services in the Luoxiao Mountain area were slowly decreasing and exhibit varying spatial distributions. (2) The residents’ well-being level increased by 181%. (3) The supply levels of water conservation, soil conservation, and carbon sequestration services, along with the population’s well-being, show a coupling coordination relationship, although with a downward trend. (4) Per capita cultivated land area, the number of industrial enterprises above a large scale, and the number of beds in social welfare centers positively influenceed changes in the coupling coordination relationship between the ecosystem services provision level and the well-being level of residents in the Luoxiao Mountain area. 【Conclusion】A robust mechanism for the industrial transformation of ecosystem services and product values should be established. Ecological industrial enterprises above scale must be vigorously developed, capitalizing on ecological resource advantages. Local residents should be actively employed, contributing to the sustained growth of their incomes to enhance the coordinated relationship between the two systems.
