黄土丘陵区不同耕作方式对土壤持水能力的影响

Effects of different tillage methods on soil water holding capacity in loess hilly area

为揭示不同耕作方式对黄土丘陵区旱作农业蓄水保墒效果形成的影响。在连续4a田间试验的基础上,分析了2021年4~10月一个完整生育期内,不同耕作方式(免耕覆盖、深松和传统耕作)对土壤水分变化及其对降雨响应过程的影响。结果表明:1)免耕覆盖土体内含水量明显高于深松和传统耕作;免耕覆盖土壤水分最大值出现在80~100cm土层,深松出现在60~80cm土层,而传统耕作出现在0~20cm土层。2)免耕覆盖和深松接纳雨水的能力明显高于传统耕作;免耕覆盖在大降雨事件下表现出更为明显的响应过程。综上,免耕覆盖能够显著提升土壤持水能力,面对大降雨乃至极端降雨事件可以显著改善土壤入渗性能。研究结果为黄土丘陵区土地资源高效利用、土地耕作方式选取提供了一定的理论数据支持。

In order to reveal the effects of different tillage methods on water storage and soil moisture conservation in rainfed farming in loess hilly area,based on the field experiment for four consecutive years,the effects of different tillage methods(no-tillage with straw cover,subsoiling tillage and conventional tillage)on soil moisture and its response to rainfall in a complete growth period from April to October 2021 were analyzed.The results showed that:1)The water content in no-tillage with straw cover soil was significantly higher than that in subsoiling and conventional tillage;the maximum soil moisture under no-tillage appeared in 80~100 cm soil layer,subsoiling tillage appeared in 60~80 cm soil layer,and conventional tillage appeared in 0~20 cm soil layer.2)The ability to receive rainwater in no-tillage and subsoiling tillage was significantly higher than that of conventional tillage;no-tillage showed a more obvious response process under heavy rainfall events.In summary,no-tillage with straw cover can significantly improve the soil water holding capacity.In the face of heavy rainfall and even extreme rainfall events,it can significantly improve the soil infiltration performance.Our research provides certain theoretical data support for the efficient utilization of land resources and the selection of land tillage methods in loess hilly areas.