Evolutions and driving mechanisms of urban blue-green spaces in northeast China: a case study with the urban central district of Harbin City

doi:10.12302/j.issn.1000-2006.202105021

JOURNAL OF NANJING FORESTRY UNIVERSITY ›› 2022, Vol. 46 ›› Issue (4): 221-229.doi: 10.12302/j.issn.1000-2006.202105021

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Evolutions and driving mechanisms of urban blue-green spaces in northeast China: a case study with the urban central district of Harbin City

SONG Shuang(), SHI Mengxi, HU Shanshan, WANG Shaohan, XU Dawei()

College of Landscape Architecture, Heilongjiang Province Key Laboratory of Germplasm Resources Development and Landscape Ecological Restoration of Cold Area Garden Plants, Northeast Forestry University, Harbin 150040, China

Received:2021-05-12 Revised:2021-08-27 Online:2022-07-30 Published:2022-08-01
Contact: XU Dawei E-mail:2607306452@qq.com;xdw_ysm@126.com

Abstract

Abstract:

【Objective】 Blue-green spaces are constantly getting eroded as a result of urbanization. The study aimed to clarify the evolutionary characteristics of blue-green spaces and their driving mechanisms, which is highly significant for guiding urban land use planning and improving the quality of the ecological environment. 【Method】 With the central district of Harbin as the study area, time nodes based on five rounds of urban master planning during 1981-2020 were selected to explore the evolutionary characteristics of blue-green spaces. A spatial econometric model was then constructed to analyze its evolutionary driving mechanisms from the viewpoint of both socio-economic and natural factors. 【Result】 (1) The cultivated land, woodland, water and wetland areas in the study region decreased significantly, whereas the grassland area increased. The relevant land-use policies and urban planning schemes issued by the government were responsible for the evolution of blue-green spaces in the study area. (2) The total proportion of blue-green spaces exhibited a decreasing trend in all gradients, and the proportion of cultivated land, water, and wetland decreased significantly in the main urban area and the suburbs. The proportion of woodland in the urban center and at the periphery of the main construction land in the adjacent Songbei District decreased slightly. Grassland increased in the main urban area. (3) From 1981 to 2017, the blue-green space evolution model of the study area was dominated by endocytosis contraction in the main urban area. From 2017 to 2020, the outlying contraction had become the main evolutionary mode of blue-green spaces. The reduction in blue-green spaces had shifted from the internal units of the urban center building land to the periphery of the urban area. (4) The evolution of various blue-green spaces was driven by various factors. Socio-economic factors were the direct driving force, with the driving effect of natural factors not as obvious. 【Conclusion】 In this study, the spatial and temporal evolution characteristics of blue-green spaces in the central district of Harbin during 1981-2020 were identified, and a spatial econometric model was used to explore the different driving effects exerted by socio-economic and natural factors on the evolution of blue-green spaces. The study provides a reference for formulating a reasonable and scientific urban blue-green space development strategy during the rapid urban expansion in northeast China.

Key words: blue-green space, urban evolution, driving mechanism, spatial econometric model, Harbin City

CLC Number:

TU984

SONG Shuang, SHI Mengxi, HU Shanshan, WANG Shaohan, XU Dawei. Evolutions and driving mechanisms of urban blue-green spaces in northeast China: a case study with the urban central district of Harbin City[J]. JOURNAL OF NANJING FORESTRY UNIVERSITY, 2022, 46(4): 221-229.

Figures/Tables 9

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1981	2020
1981	耕地 cultivated land	林地 woodland	草地 grassland	水域及湿地 water and wetland	建设用地 construction land	未利用地 unused land	总计 total	转出 transfer out
耕地cultivated land	2 700.846 9	0.196 2	3.380 4	12.128 4	297.553 5	5.770 8	3 019.876 2	319.029 3
林地woodland	0.875 7	163.881 9	0.000 0	8.953 2	5.253 3	0.396 9	179.361 0	15.497 1
草地grassland	2.144 7	0.040 5	82.440 0	0.819 0	1.781 1	0.000 0	87.225 3	4.785 3
水域及湿地water and wetland	25.588 8	0.000 0	3.523 5	490.753 8	18.390 6	0.000 0	538.256 7	47.502 9
建设用地construction land	1.747 8	0.000 0	0.006 3	0.203 4	368.884 8	0.067 5	370.909 8	2.025 0
未利用地unused land	0.000 0	0.000 0	0.000 0	0.000 0	1.123 2	0.309 6	1.432 8	1.123 2
总计total	2 731.203 9	164.118 6	89.350 2	512.857 8	692.986 5	6.544 8	4 197.061 8
转入transfer into	30.357 0	0.236 7	6.910 2	22.104 0	324.101 7	6.235 2

时期 stage	斑块数量占比/% number proportion			斑块面积占比/% area proportion
时期 stage	飞地式 outlying	边缘式 edging	内吞式 endocytosis	飞地式 outlying	边缘式 edging	内吞式 endocytosis
1981—1996	23.81	14.29	61.90	2.50	18.16	79.34
1996—2004	10.00	23.33	66.67	1.02	3.08	95.90
2004—2011	26.67	40.00	33.33	6.14	11.18	82.68
2011—2017	25.45	50.91	23.64	1.75	5.99	92.26
2017—2020	30.77	56.41	12.82	12.02	85.58	2.40

模型 model	拉格朗日乘数 LM	稳健拉格朗日乘数 rubust LM	拟合优度 R²	似然比率 LR	赤池信息准则 AIC	施瓦茨准则 SC
SEM	289.460 9	30.392 0	0.602 8	428.286 2	3 201.273 6	3 481.03
SLM	273.182 0	4.291 8	0.573 0	398.283 7	3 592.281 3	3 571.82

指标 indicators	解释变量 variable	耕地 cultivated land	林地 woodland	草地 grassland	水域及湿地 water and wetland
常数项		0.271 8	0.127 3	0.382 9	0.102 6
社会经济因素 socio- economic factors	人口空间分布	-0.372 4^***	0.184 0^***	0.326 1^***	0.114 5^**
	人均GDP	-0.081 3^**	0.103 2^**	0.667 3^**	0.034 2^*
	第三产业GDP占比	-0.016 4^**	-0.021 9^**	-0.006 7^***	0.532 8^***
	城镇化率	-0.158 4^***	0.123 5^**	0.692 0^***	-0.306 1^*
	绿化投资额	-0.139 2^**	0.091 9^*	0.431 0^**	0.459 1^**
	林业投资额	0.046 2	0.716 2^***	0.040 9	0.130 9
	农业总产值	0.110 9^**	-0.283 4	-0.158 3	-0.384 0
自然因素 natural factors	DEM	-0.247 2^*	0.493 9^*	-0.320 1^**	-0.294 3^*
	坡度	-0.203 0	-0.320 1^*	-0.043 9	-0.034 5^*
	土壤有机碳	0.362 9^**	0.249 2^*	0.274 5^*	-0.094 1^*
	年平均气温	-0.384 0^**	-0.283 9^**	0.093 2^**	-0.081 4^**
	年降水量	0.135 8^*	0.154 9^*	0.101 8^*	0.063 2^*

Evolutions and driving mechanisms of urban blue-green spaces in northeast China: a case study with the urban central district of Harbin City

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