南京林业大学学报(自然科学版) ›› 2021, Vol. 45 ›› Issue (6): 127-134.doi: 10.12302/j.issn.1000-2006.202101035

• 研究论文 • 上一篇    下一篇

油茶林生草栽培对地表径流及氮磷流失特征的影响

陈隆升1(), 梅莉2,*(), 陈永忠1, 赵泽尧2, 许彦明1, 张震1, 胡亚军3, 刘彩霞1, 苏以荣3   

  1. 1. 湖南省林业科学院,国家油茶工程技术研究中心,湖南 长沙 410004
    2. 华中农业大学园艺林学学院,湖北省林业信息工程技术研究中心,湖北 武汉 430070
    3. 中国科学院亚热带农业生态研究所,湖南 长沙 410125
  • 收稿日期:2021-01-29 接受日期:2021-07-30 出版日期:2021-11-30 发布日期:2021-12-02
  • 通讯作者: 梅莉
  • 基金资助:
    国家重点研发计划(2017YFC0505503);湖南省科技重大专项项目(2018NK1030)

Effects of interplanting herbage on surface runoff associated with nitrogen and phosphorus losses in Camellia oleifera plantations

CHEN Longsheng1(), MEI Li2,*(), CHEN Yongzhong1, ZHAO Zeyao2, XU Yanming1, ZHANG Zhen1, HU Yajun3, LIU Caixia1, SU Yirong3   

  1. 1. National Engineering Research Center for Oil-tea Camellia, Hunan Academy of Forestry, Changsha 410004,China
    2. College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Hubei Engineering Technology Research Center for Forestry Information, Wuhan 430070, China
    3. Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125,China
  • Received:2021-01-29 Accepted:2021-07-30 Online:2021-11-30 Published:2021-12-02
  • Contact: MEI Li

摘要: 目的 研究间种草本植物对油茶林地表径流以及随径流流失的溶解态氮磷的影响,以期降低油茶林面源污染风险并改善下游水体环境,为油茶高效生态经营提供参考。方法 选取林下植被覆盖度低的5年生油茶幼林,设计3个试验处理:无间种对照、间种百喜草和间种金鸡菊,每个试验处理面积600 m2,3次重复,同时,在每个试验样地建设水平投影为16 m×7 m的标准径流监测小区,共计9个径流监测区。经过2年的生草处理后,间种百喜草和金鸡菊的油茶林下植被覆盖度从对照的31.13%分别提高到90.47%和80.40%。在此基础上,通过土壤理化性质测定、多场次的地表径流及其氮磷含量的监测,比较各处理样地的地表径流量、土壤侵蚀量、径流溶解态氮(DN)和溶解态磷(DP)流失量的变化特征,分析南方油茶幼林生草栽培对地表径流及氮磷流失的影响。结果 油茶林下间种百喜草和金鸡菊2年后,土壤有机质、全氮及全磷含量均比对照有增加趋势。2020年6—7月,在试验区共观测到5场侵蚀性降雨事件。与对照处理相比,间种百喜草和金鸡菊的处理在5场侵蚀性降雨事件中均显著降低了地表径流量和土壤侵蚀量(P<0.05)。与对照相比,间种百喜草和金鸡菊处理的地表总径流量分别减少了35.04%和33.56%,土壤累积侵蚀量分别减少了83.89%和79.85%。不同场次径流中DN和DP浓度变化趋势不一致,第1和第2场径流中DN浓度较低而DP浓度较高,第4和第5场径流中DN浓度较高而DP浓度较低。所有观测场次的径流DN和DP浓度均值超过了GB 3838—2002《地表水环境质量标准》中总氮、总磷Ⅴ类标准限值。与对照相比,间种百喜草能够显著降低径流中DN和DP浓度(P<0.05),减少量分别为4.67%和16.88%;而间种金鸡菊后径流DP浓度显著降低了16.88%(P<0.05),但DN浓度却增加了5.14%(P<0.05)。总体上,与对照处理相比,间种百喜草和金鸡菊分别降低了径流DN流失量26.66%和21.49%、径流DP流失量63.06%和50.57%。结论间种百喜草和金鸡菊的油茶林地显著降低了地表径流量和土壤侵蚀量,显著减少了径流溶解态氮磷流失量,相较而言,油茶幼林间种百喜草对林地地表径流及其可溶性氮磷流失的阻控效果比间种金鸡菊的好。

关键词: 油茶林, 金鸡菊, 百喜草, 氮、磷流失, 地表径流

Abstract:

【Objective】 This study investigated the effects of interplanting herbaceous plants on surface runoff associated with nitrogen and phosphorus losses in the Camellia oleifera plantation to reduce agricultural non-point source pollution risk and improve downstream water environments. These findings would provide solutions for the efficient ecological management of this economic orchard system.【Method】 Three treatments with three replicates were designed for this experiment: ① non-interplanting as the control (CK), ② interplanting Paspalum notatum (T1), and ③ interplanting Coreopsis basalis (T2). A 5-year-old Camellia oleifera plantation was selected as the study site, which had a high risk of soil erosion because of the low coverage of inter-row grasses. Nine independent 600 m 2 plots were randomly arranged for this experiment. In each plot, a standard runoff monitoring unit with horizontally projected areas (16 m × 7 m) was established. After two years’s growth of sown grass in the C. oleifera plantation, the coverage of inter-row for P. notatum and C. basalis increased to 90.47% and 80.40%, respectively, compared with 31.13% coverage in the control treatment. Based on this background, the soil physical and chemical properties, including soil organic carbon, total nitrogen, and phosphorus, were determined. The surface runoff associated with nitrogen and phosphorus content in each plot from June to July in 2020 was monitored. The variations in surface runoff, soil erosion, runoff dissolved nitrogen (DN), and DN loss in different treatments were compared to determine which grass could provide a better protection from soil erosion and decrease the nitrogen and phosphorus loss.【Result】 After two years of sowing grasses, increasing trends in soil organic carbon, total nitrogen and phosphorus were found both in interplanting P. notatum and C. basalis treatments. Five erosive rainfall events were observed in the study area, from June to July 2020. Compared to the control treatment, both interplanting P. notatum and Coreopsis basalis significantly reduced surface runoff and soil erosion (P<0.05), with the total surface runoff decreasing by 35.04% and 33.56%, and the total soil erosion decreasing by 83.89% and 79.85%, respectively. The variation trends of DN and dissolved phosphorus (DP) concentrations in the different runoff events were not consistent. In the first and second runoff events, the concentration of DN was low and the concentration of DP was high, while in the fourth and fifth runoff events, the opposite results were observed, with high concentrations of DN and low concentrations of DP. The average values of DN and DP concentrations in all observed runoff events exceeded the Class V level of nitrogen and phosphorus in surface water according to the GB 3838-2002 Environmental Quality Standard for Surface Water. Compared with the control treatment, interplanting P. notatum significantly reduced the concentration of DN and DP by 4.67% and 16.88%, respectively (P<0.05). Interplanting C. basalis significantly reduced DP concentration by 16.88% (P<0.05), whereas DN concentration increased by 5.14% (P<0.05). In total, interplanting P. notatum and C. basalis reduced the loss of DN by 26.66% and 21.49% and DP by 63.06% and 50.57%, respectively.【Conclusion】 Both interplanting P. notatum and C. basalis significantly reduced surface runoff, soil erosion, DN and DP loss. Interplanting P. notatum was better than C. basalis for the protection from soil erosion in C. oleifera plantations.

Key words: Camellia oleifera plantation, Coreopsis basalis, Paspalum notatum, nitrogen and phosphorus loss, surface runoff

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