Quan Yanying, Hutjes Ronald W A, Biemans Hester, Zhang Fusuo, Chen Xinping, Chen Xuanjing
Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin, College of Resources and Environment, Southwest University, Tiansheng Road 02, Chongqing, 400715, China; Water Systems and Global Change Group, Wageningen University & Research, Droevendaalsesteeg 3, 6708, PB Wageningen, the Netherlands.
Water Systems and Global Change Group, Wageningen University & Research, Droevendaalsesteeg 3, 6708, PB Wageningen, the Netherlands.
J Environ Manage. 2023 Oct 27;348:119376. doi: 10.1016/j.jenvman.2023.119376.
Balancing ecology and human development has been a long and wide concern. The upper Yangtze River Basin (UYRB) of China has implemented large important ecological restoration projects since the last century. These restoration practices have changed land use patterns within the UYRB, consequently impacting the local carbon cycle. The most noteworthy project is the Grain for Green Program, which returns cropland to natural vegetation (forest and grassland). Yet the effects of restoration on land use change, carbon sequestration, and associated food production remain unclear. This study utilized remote sensing data and conversion coefficients to analyze the ecological-policy-induced land use changes of the UYRB from 2000 to 2020 and their impacts on terrestrial carbon sequestration. Linear regression, machine learning, and structural equation modeling (SEM) were utilized to evaluate the correlations between environmental and socio-economic factors and the distribution of carbon stocks. The results indicated positive effects of ecological activities on the UYRB, despite decreases in cropland. Over the past 20 years, the UYRB had sequestered carbon by a total amount of 1796 ± 926 Mt C. The spatial distribution of sequestered carbon demonstrated a strong correlation with slopes, followed by temperatures. The SEM results indicated that agricultural production and carbon sequestration were enhanced synergically under land use changes. This further demonstrated the effectiveness of these land policies in achieving a balance between crop productivity and ecology protection. We emphasized the importance of vegetation restoration in achieving carbon neutrality and the necessity to continue these projects. We suggested a more reasonable land management for the future UYRB based on the characteristics of each geographical subregion. This work serves as an example of effective land management to other locations worldwide perusing the harmony of ecological restoration and human development.
平衡生态与人类发展一直是长期以来广泛关注的问题。自上世纪以来，中国长江上游流域（UYRB）实施了多项重要的生态修复工程。这些修复措施改变了长江上游流域的土地利用模式，进而影响了当地的碳循环。最值得注意的项目是退耕还林还草工程，该工程将农田恢复为自然植被（森林和草地）。然而，生态修复对土地利用变化、碳固存及相关粮食生产的影响仍不明确。本研究利用遥感数据和转换系数，分析了2000年至2020年长江上游流域因生态政策导致的土地利用变化及其对陆地碳固存的影响。利用线性回归、机器学习和结构方程模型（SEM）评估环境和社会经济因素与碳储量分布之间的相关性。结果表明，尽管耕地面积减少，但生态活动对长江上游流域仍产生了积极影响。在过去20年里，长江上游流域共固碳1796±926 Mt C。固碳的空间分布与坡度密切相关，其次是温度。结构方程模型结果表明，土地利用变化下农业生产和碳固存协同增强。这进一步证明了这些土地政策在实现作物生产力与生态保护平衡方面的有效性。我们强调了植被恢复在实现碳中和方面的重要性以及继续实施这些项目的必要性。我们建议根据每个地理分区的特点，对未来的长江上游流域进行更合理的土地管理。这项工作为世界其他地区寻求生态修复与人类发展和谐的地方提供了有效土地管理的范例。
