<?tk 4?>In the context of global climate change, quantifying the response mechanism of vegetation carbon sinks to climate variability is essential for understanding the terrestrial carbon cycle. Therefore, this study proposed the Vegetation Carbon Response Sensitivity Index (VCRSI) to characterize the sensitivity of vegetation gross primary productivity (GPP) to multiple climatic factors. Based on the GPP data driven by solar-induced chlorophyll fluorescence, combined with the four climate variables of temperature, precipitation, soil moisture and solar radiation, the sensitivity of vegetation carbon sink to climate change and its spatial evolution characteristics in China from 1981 to 2018 were systematically evaluated by using the random forest regression model with 5-year moving time window and parameter optimization. The results showed that VCRSI exhibited a southeast‑high and northwest‑low spatial pattern. The high-value areas were concentrated in the eastern south temperate to mid-subtropical regions such as the North China Plain, Fuzhou Plain and Wenhuang Plain. Although the surrounding area of the Qinghai-Tibet Plateau is generally low, the local value is high. Among different vegetation types, the VCRSI of agricultural ecosystem was significantly higher than that of grassland and coniferous and broad-leaved mixed forest. The dominant climatic factors have regional differences. Water factors (precipitation and soil moisture) dominate VCRSI changes in temperate and subtropical regions, while temperature plays a major role in the Qinghai-Tibet Plateau and high latitudes. The VCRSI proposed in this study effectively integrates multi-factor-driven carbon sink sensitivity information, and provides a quantitative basis for analyzing the response mechanism of China’s ecosystem to climate change and optimizing carbon sink management strategies. Graphical Abstract <?tk 4?>In this study, the total primary productivity (GPP) data was used as the response variable, combined with four key climatic factors: temperature, precipitation, soil moisture, and solar radiation. The vegetation carbon response sensitivity index (VCRSI) was constructed through a five-year moving time window and a random forest regression model with parameter optimization. Based on a systematic evaluation of the sensitivity of vegetation ecosystem carbon sinks to climate change and their spatial evolution characteristics across China from 1981 to 2018, our results indicate that the spatial pattern of the Vegetation Carbon Response Sensitivity Index (VCRSI) exhibits a southeast‑high and northwest‑low gradient distribution. The VCRSI values in the southern temperate zone, northern subtropical zone and central subtropical zone in eastern China were relatively high, and the high value areas were mainly distributed in the North China Plain, Fuzhou Plain, Wenhuang Plain and other regions. The VCRSI value of the plateau climate region in western China is generally low, but the VCRSI value of the surrounding area of the Qinghai-Tibet Plateau is relatively high. Moreover, the dominant climatic factors showed significant regional differentiation characteristics: in temperate and subtropical regions, water factors (precipitation, soil moisture) dominated the change of VCRSI; in the Qinghai-Tibet Plateau and high latitudes, temperature plays a leading role.

Sensitivity of Vegetation Carbon Sink Potential to Climate Change in China

期刊论文
发表日期：

2026年4月1日

查看全文

Lilin Kong,
Shengqi Jian,
Jiayi Wang

摘要

In the context of global climate change, quantifying the response mechanism of vegetation carbon sinks to climate variability is essential for understanding the terrestrial carbon cycle. Therefore, this study proposed the Vegetation Carbon Response Sensitivity Index (VCRSI) to characterize the sensitivity of vegetation gross primary productivity (GPP) to multiple climatic factors. Based on the GPP data driven by solar-induced chlorophyll fluorescence, combined with the four climate variables of temperature, precipitation, soil moisture and solar radiation, the sensitivity of vegetation carbon sink to climate change and its spatial evolution characteristics in China from 1981 to 2018 were systematically evaluated by using the random forest regression model with 5-year moving time window and parameter optimization. The results showed that VCRSI exhibited a southeast‑high and northwest‑low spatial pattern. The high-value areas were concentrated in the eastern south temperate to mid-subtropical regions such as the North China Plain, Fuzhou Plain and Wenhuang Plain. Although the surrounding area of the Qinghai-Tibet Plateau is generally low, the local value is high. Among different vegetation types, the VCRSI of agricultural ecosystem was significantly higher than that of grassland and coniferous and broad-leaved mixed forest. The dominant climatic factors have regional differences. Water factors (precipitation and soil moisture) dominate VCRSI changes in temperate and subtropical regions, while temperature plays a major role in the Qinghai-Tibet Plateau and high latitudes. The VCRSI proposed in this study effectively integrates multi-factor-driven carbon sink sensitivity information, and provides a quantitative basis for analyzing the response mechanism of China’s ecosystem to climate change and optimizing carbon sink management strategies.

Graphical Abstract

In this study, the total primary productivity (GPP) data was used as the response variable, combined with four key climatic factors: temperature, precipitation, soil moisture, and solar radiation. The vegetation carbon response sensitivity index (VCRSI) was constructed through a five-year moving time window and a random forest regression model with parameter optimization. Based on a systematic evaluation of the sensitivity of vegetation ecosystem carbon sinks to climate change and their spatial evolution characteristics across China from 1981 to 2018, our results indicate that the spatial pattern of the Vegetation Carbon Response Sensitivity Index (VCRSI) exhibits a southeast‑high and northwest‑low gradient distribution. The VCRSI values in the southern temperate zone, northern subtropical zone and central subtropical zone in eastern China were relatively high, and the high value areas were mainly distributed in the North China Plain, Fuzhou Plain, Wenhuang Plain and other regions. The VCRSI value of the plateau climate region in western China is generally low, but the VCRSI value of the surrounding area of the Qinghai-Tibet Plateau is relatively high. Moreover, the dominant climatic factors showed significant regional differentiation characteristics: in temperate and subtropical regions, water factors (precipitation, soil moisture) dominated the change of VCRSI; in the Qinghai-Tibet Plateau and high latitudes, temperature plays a leading role.