Altered drying-rewetting patterns due to climate change may affect soil nitrogen (N) and phosphorus (P) cycling in terrestrial ecosystems. The responses of soil N and P cycling to drying and rewetting cycles can vary with drying-rewetting patterns, experimental methods, ecosystems, and soil types, thus making a synthesis of these studies necessary for understanding mechanisms and predicting future responses to climate change. Here, we compiled data of 1882 observations from 79 studies for a meta-analysis of the responses of soil N and P pools and fluxes to drying and rewetting and how these responses are modified by experimental conditions. Results showed that 1) experimental drying increased NH₄⁺, extractable organic nitrogen (EON), and available P in the soil significantly by 22, 27, and 72%, respectively. In contrast, soil NO₃⁻, enzymatic activities, microbial biomass, net nitrification, and N₂O emissions significantly decreased by 37, 13–21, 21–28, 39, and 93%, respectively. 2) Upon rewetting of dried soil, soil EON, extractable organic phosphorus (EOP), net N mineralization, nitrification, phosphatase activity, dissolved organic N leaching, dissolved inorganic P leaching, and N₂O emissions significantly increased by 59, 27, 19, 15, 12, 60, 116, and 218%, respectively, while soil NO₃⁻ and NO₃⁻ leaching significantly decreased by 9 and 74%, respectively. Soil microbial N and P as well as enzymatic activities recovered from drought during the rewetting phase. The mean effect sizes of drying and rewetting generally increased with drying intensity, which was probably also the main reason for greater effect sizes observed in laboratory than in field experiments. Our meta-analysis showed stronger positive responses of available P to drying and rewetting than mineral N, which agreed with greater effect sizes on P than on N leaching. This suggests that drying and rewetting induce an imbalance between N and P, which was more pronounced in soils from forests than from agricultural systems. Overall, these results imply that the expected increase in the frequency and intensity of droughts potentially decouples the cycling of P and N, with consequences for nutrient leaching and the supply of plants and microorganisms with these nutrients.

由于气候变化而导致的干湿重覆模式的改变可能会影响陆地生态系统中土壤氮（N）和磷（P）的循环。土壤N和P循环对干燥和再湿润循环的响应会随干燥再湿模式，实验方法，生态系统和土壤类型而变化，因此这些研究的综合对于理解机理和预测未来对气候变化的响应是必要的。在这里，我们收集了来自79项研究的1882个观测值的数据，用于对土壤N和P池以及通量对干燥和再湿润的响应以及实验条件如何改变这些响应的荟萃分析。结果表明：1）实验干燥增加了NH ₄ ⁺，可萃取有机氮（EON）和土壤中的有效磷分别显着增加22％，27％和72％。与此相反，土壤NO ₃ ^- ，酶活性，微生物生物量，净硝化，和N ₂ O排放显著13-21，21-28，39，和93％，分别减少了37。2）对干土壤重新湿润后，土壤EON，可萃取有机磷（EOP），净氮矿化，硝化，磷酸酶活性，溶解性有机氮淋溶，溶解性无机P淋溶和N ₂ O排放量显着增加59、27、19 ，15％，分别为12，60，116，和218％，而土壤NO ₃ ^-和NO ₃ ^-浸出分别显着减少了9％和74％。在再湿润阶段，土壤微生物氮和磷以及酶活性从干旱中恢复。干燥和再湿润的平均效果大小通常随干燥强度的增加而增加，这可能也是在实验室观察到的效果大小大于现场实验的主要原因。我们的荟萃分析显示，有效磷对干燥和再湿润的反应比矿物氮更强，与磷相比，磷对氮的影响更大。这表明干燥和再润湿会导致N和P之间的不平衡，这在森林土壤中比农业系统土壤中更为明显。总体而言，这些结果表明，干旱频率和强度的预期增加可能会破坏P和N的循环，