There is a limited understanding of agricultural land dynamics across global drylands and the impacts of transitions between agricultural land and land cover on net primary productivity (NPP) changes. This study attempted to fill this gap by examining agricultural land changes and NPP responses in drylands. A data‐driven assessment of effects on the NPP of individual agricultural land displacement was carried out using three methods: the mean difference method, a newly introduced ridge‐regression method, and a proposed method based on actual change excluding climate impact. Increases in NPP were accompanied by agricultural land transitions from natural land cover and expected forests. The agricultural expansion mainly replaced sparse vegetation and grassland and increased the overall NPP of the dryland ecosystem. The mean difference method and ridge‐regression method overestimated the NPP increase caused by agricultural land expansion. Land use change contributed more than 70% to NPP increase in the new agricultural area. However, land use change has less effect on total NPP in drylands than climate change. Monitoring agricultural land dynamics and distinguishing NPP changes caused by different agricultural land transitions is helpful for targeted management and sustainable development of agriculture in drylands.

中文翻译：

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量化净初级生产力对旱地农业扩张的响应

对全球干旱地区的农业土地动态以及农业土地和土地覆盖之间的过渡对净初级生产力（NPP）变化的影响的了解有限。这项研究试图通过研究旱地的农业用地变化和NPP响应来填补这一空白。以数据驱动的评估方法，使用三种方法对单个农业用地流离失所的NPP进行了评估：均值差分法，新引入的岭回归法和基于实际变化（不包括气候影响）的拟议方法。NPP的增加伴随着从自然土地覆盖和预期森林的农业用地过渡。农业扩张主要取代了稀疏的植被和草地，并增加了旱地生态系统的整体NPP。均值差法和岭回归法高估了由农业用地扩张引起的NPP增长。土地利用变化为新农业区的NPP增长贡献了70％以上。然而，与气候变化相比，土地利用变化对旱地总NPP的影响较小。监测农业用地动态并区分由不同的农业用地过渡造成的NPP变化，有助于有针对性的管理和旱地农业的可持续发展。