ABSTRACT

Improving our understanding of land-use change is critical for water management in semi-arid areas, due to its effects on the hydrological cycle. In the U.S. Southwest, fallowing farmland has become one strategy to reduce water use. Previous to this study, the magnitude and location of changes in fallowing have not been studied in depth. Using the 30-meter Cropland Data Layer, this study assessed the spatial and temporal patterns of fallowing in the U.S. portion of the Rio Grande/Río Bravo Basin (RGB) at three spatial scales (basin, state, and ecoregion) between 2008 and 2018. Our results do not show evidence of an increasing trend in fallowing at the basin level. However, the spatio-temporal patterns differed considerably among states and ecoregions, revealing hotspots of fallowing. By showing that land fallowing is not a widespread practice across the basin, our findings indicate that the potential of this strategy to save water has been underused.

摘要

由于土地利用变化对水文循环的影响，提高我们对土地利用变化的理解对于半干旱地区的水资源管理至关重要。在美国西南部，休耕农田已成为减少用水的一种策略。在此研究之前，尚未深入研究休耕变化的幅度和位置。本研究使用 30 米农田数据层，评估了 2008 年至 2018 年间在三个空间尺度（盆地、州和生态区）的里奥格兰德/里奥布拉沃盆地 (RGB) 美国部分休耕的时空模式. 我们的结果没有显示流域水平休耕增加趋势的证据。然而，各州和生态区之间的时空模式差异很大，揭示了休耕的热点。