Department of Environmental Science and Engineering, Fudan University, 2005 Songhu Road, Shanghai 200438, PR China.
Tongji Urban Planning and Design Institute Co., Ltd, 2 Zhongshan North Road, Shanghai, PR China.
Sci Total Environ. 2022 Aug 1;832:154979. doi: 10.1016/j.scitotenv.2022.154979. Epub 2022 Apr 2.
The provision of ecosystem services (ESs) such as carbon sequestration and grain provision are critical components to sustainable development. Reaching carbon neutrality generally requires the growing carbon sequestration of forest land, and feeding a growing population needs an expansion of cultivated land. However, limited land resources may lead to a contradiction between the carbon sequestration and grain provision. China has proposed long-term and large-scale land use programs, and exploring whether these land use policies are effective for ES sustainable provision would be instructive for future policy implications. This study integrated multi-source data in the socioecological dimension to determine the extent by which land use and land use change influence the supply-demand mismatches of carbon (carbon sequestration and emission) and grain (grain provision and consumption) in China at the provincial level. The result showed that the total quantity of carbon emissions surpassed carbon sequestration and the grain provision could cover the consumption from 2000 to 2015. Spatially, southeastern coastal provinces had higher grain deficits and northeast provinces had higher carbon deficits. This study further detected the influencing factors of the mismatches between the supply and demand of the two ESs. Excluding land use factors, our results showed that social factors contributed 38% and 47% to the supply-demand mismatches of carbon and grain, respectively, and natural factors contributed 39% and 15%, respectively. During 2000-2005, 2005-2010, and 2010-2015, cropland changes significantly affected grain balance, while forest land changes did not significantly affect carbon balance. These results indicated that cropland protections are vital to food safety, and carbon emission reductions should be the focus for carbon balance. Finally, this study makes policy suggestions for land use and ecosystem management, and a future research framework was proposed to help mitigate ES supply-demand imbalance.
生态系统服务（ESs）的提供，如碳固存和粮食供应，是可持续发展的关键组成部分。实现碳中和通常需要增加林地的碳固存，而养活不断增长的人口则需要扩大耕地。然而，有限的土地资源可能导致碳固存和粮食供应之间的矛盾。中国提出了长期和大规模的土地利用规划，探索这些土地利用政策对 ES 可持续供应的有效性，将为未来的政策意义提供指导。本研究综合了社会生态维度的多源数据，以确定土地利用和土地利用变化在多大程度上影响中国省级水平碳（碳固存和排放）和粮食（粮食供应和消费）的供需不匹配。结果表明，碳排放量总量超过了碳固存量，2000 年至 2015 年期间粮食供应可以覆盖消费。从空间上看，东南沿海省份粮食短缺较大，东北省份碳短缺较大。本研究进一步检测了这两种 ES 供需不匹配的影响因素。在排除土地利用因素的情况下，我们的结果表明，社会因素分别对碳和粮食的供需不匹配贡献了 38%和 47%，自然因素分别贡献了 39%和 15%。在 2000-2005 年、2005-2010 年和 2010-2015 年期间，耕地变化显著影响粮食平衡，而林地变化对碳平衡没有显著影响。这些结果表明，耕地保护对粮食安全至关重要，减少碳排放应成为碳平衡的重点。最后，本研究为土地利用和生态系统管理提出了政策建议，并提出了一个未来的研究框架，以帮助缓解 ES 供需失衡。
