县域绿色空间景观格局对碳汇的影响—— 以长三角为例

The Impact of Green Space Landscape Pattern onCarbon Sequestration at the County-level: A CaseStudy of the Yangtze River Delta

关键词:  风景园林  绿色空间  景观格局  碳汇  空间回归

Key words:  landscape architecture  green space  landscape pattern  carbon sequestration  spatial regression

摘要:

：绿色空间是碳汇最有效的要素之一，但绿色空间格 局与碳汇之间的关系鲜有研究涉及，尤其基于地理空间的视 角。针对长三角地区县域单元，从5个维度各选取1个景观格 局指标衡量绿色空间的形态特征，采用地理加权回归模型揭 示绿色空间格局对碳汇影响的空间分异特征。结果表明，长 三角县域单元的碳汇量存在显著的空间自相关，地理加权回 归模型相比传统回归模型能更好地呈现影响机制。绿色空间 的景观形状指数对碳汇的贡献最大，并在所有县域单元中对 碳汇均起到促进作用；其次为最大斑块指数，以促进作用为 主导；边缘密度对碳汇的作用呈双面性，促进与抑制作用的 县域单元数量相当；香农均匀性指数和斑块密度的贡献相对 最小。此外，5个指标对碳汇影响的强弱程度与促进、抑制作 用也表现出空间上的差异。研究结果从助力碳中和的角度为 县域层面的绿色空间优化提供了一些参考。

Abstract:

Green space is one of the most effective elements for carbon sequestration, but the relationship between green space pattern and carbon sequestration is rarely studied, especially from the perspective of geographical space. For the county-level units in the Yangtze River Delta, five landscape pattern indexes are selected from five dimensions to measure the morphological characteristics of green space. The geographical weighted regression model is used to reveal the spatial differentiation characteristics of the impact of green space pattern on carbon sequestration. Results show that there is significant spatial autocorrelation in the carbon sequestration in counties in the Yangtze River Delta. The geographical weighted regression model can better present the impact mechanism than that of the traditional regression model. The landscape shape index of green space contributes the most to carbon sink, and plays a role in promoting carbon sequestration in all county units, followed by the largest patch index, which is dominated by the promotion effect. The effect of edge density on carbon sequestration is twosided, and the number of county units that promote and inhibit the effect is equal. Shannon's evenness index and patch density have the minimal contribution. In addition, the intensity of the impact of the five indexes on carbon sequestration and their promotion and inhibition shows spatial differences. The study provides some references for the optimization of green space at the county level from the perspective of helping carbon neutrality.