College of Water Conservancy and Transportation, Zhengzhou University, Zhengzhou, 450001, China.
Yellow River Institute of Hydraulic Research, Yellow River Conservancy Commission, Zhengzhou, 450003, China.
Environ Sci Pollut Res Int. 2024 Jun;31(30):42840-42856. doi: 10.1007/s11356-024-33842-5. Epub 2024 Jun 15.
A crucial physiological indicator known as water use efficiency (WUE) (Foley et al.) assesses the trade-off between water loss and carbon uptake. The carbon and water coupling mechanisms, energy balance, and hydrological cycle processes in the ecosystem are impacted by climate change, vegetation dynamics, and land use change. In this study, we employed Sen trend analysis, the Mann-Kendall test, the land-use transfer matrix, and multiple linear regression analysis to investigate the regional and temporal dynamics of WUE and its reaction to climate change and land-use transfer changes in China. According to the findings, the annual average WUE in China was 0.998 gC/mm·m from 2000 to 2017. Of the nine major river basins, the Continental Basin had the lowest WUE (0.529 gC/mm·m), and the Southwest River Basin had the highest WUE (0.691 gC/mm·m), while the Pearl River Basin and the Southeast River Basin had the highest WUEs (1.184 gC/mm·m). The Haihe River Basin and the Yellow River Basin were the key regions with elevated WUE. Forest had the greatest WUE (1.134 gC/mm·m; out of the nine major river basins), followed by shrub (1.109 gC/mm·m). Vegetation dynamics changes had a higher impact on WUE than climate change and land use changes, when the contributions of climate change, vegetation dynamics changes, and land use changes to WUE were separated. The largest climatic factor influencing variations in WUE was VPD (28.04% ± 3.98%), whereas among the vegetation dynamics factors, NDVI (33.75% ± 6.90%) and LAI (22.21% ± 2.11%) contributed the most. The transition from high to low vegetation cover led to a relative decrease in WUE, and vice versa, according to data on land use change in China from 2000 to 2017. Land use change made a positive impact to WUE change. The findings of this study may be helpful in China for choosing a suitable regional plant cover and managing local water resources sustainably.
一个关键的生理指标，即水分利用效率（WUE）（Foley 等人），评估了水分损失和碳吸收之间的权衡。气候变化、植被动态和土地利用变化会影响生态系统中的碳水耦合机制、能量平衡和水文循环过程。在这项研究中，我们采用 Sen 趋势分析、Mann-Kendall 检验、土地利用转移矩阵和多元线性回归分析，研究了中国 WUE 的区域和时间动态及其对气候变化和土地利用转移变化的反应。研究结果表明，2000 年至 2017 年，中国年平均 WUE 为 0.998 gC/mm·m。在 9 个主要流域中，内陆流域的 WUE 最低（0.529 gC/mm·m），西南流域的 WUE 最高（0.691 gC/mm·m），而珠江流域和东南流域的 WUE 最高（1.184 gC/mm·m）。海河流域和黄河流域是 WUE 升高的关键区域。森林的 WUE 最大（1.134 gC/mm·m；在 9 个主要流域中），其次是灌木（1.109 gC/mm·m）。当分离气候变化、植被动态变化和土地利用变化对 WUE 的贡献时，植被动态变化对 WUE 的影响大于气候变化和土地利用变化。对 WUE 变化影响最大的气候因素是 VPD（28.04%±3.98%），而在植被动态因素中，NDVI（33.75%±6.90%）和 LAI（22.21%±2.11%）的贡献最大。根据 2000 年至 2017 年中国土地利用变化的数据，高植被覆盖向低植被覆盖的转变导致 WUE 相对降低，反之亦然。土地利用变化对 WUE 变化有积极影响。本研究结果可能有助于中国选择适宜的区域植被覆盖，实现当地水资源的可持续管理。
