深松耕作和秸秆还田对农田土壤物理特性的影响

[目的]为了增加中国干旱半干旱地区农田土壤蓄水保墒能力。[方法]采用野外试验和室内分析相结合的方法研究了深松和深松结合秸秆还田耕作技术对晋中北部地区两种主要类型土壤物理特性的影响。[结果]深松可以打破土壤犁底层,显著降低黏土和壤土10—30cm土层范围内的土壤容重;调节土壤孔隙度,增加了黏土10—30cm土层范围内的土壤总孔隙度、毛管孔隙度和非毛管孔隙度,同时增加壤土10—30cm土层土壤总孔隙度、毛管孔隙度和20—30cm土层土壤非毛管孔隙度;改善黏土和壤土20—30cm土层土壤固、液、气3相状况;深松结合连年秸秆还田进一步优化了壤土耕层环境,同时显著降低了玉米拔节期土壤地表结皮的厚度和紧实度。[结论]深松结合连年秸秆还田和深松耕作技术可以缓解土壤板结状况,增加降雨入渗。

Effects of Subsoiling Tillage and Straw Returning to Field on Soil Physical Properties

[Objective] In order to increase soil moisture conservation in arid and semi-arid areas of China.[Methods] Field experiment combined with indoor analysis was conducted in fluvo-aquic soil(clay) and cinnamon soil(loam) in North Central Shanxi Province.[Results] Subsoiling tillage broke the plow layer, significantly reduced soil bulk density at 10-30 cm soil layer and regulated soil porosity, including increasing soil total porosity, capillary porosity and non-capillary porosity at 10-30 cm soil layers on clay soil. Moreover, soil total porosity and capillary porosity at 10-30 cm soil layer, non-capillary porosity at 20-30 cm soil layer on loam soil were increased. Subsoiling tillage improved soil solid, liquid and gas phase conditions at 20-30 cm soil layer both on clay and loam. Subsoiling tillage with straw incorporated further optimized the farming environment, significantly reduced crust thickness and compaction of surface soil on the jointing stage of maize.[Conclusion] Subsoiling tillage with straw incorporated and subsoiling tillage can alleviate soil hardening conditions of the farming ground and increased rainfall infiltration.