砾石覆盖下的农田土壤环境效应:研究进展与展望

Soil environmental effects of gravel-sand mulched field:research grogress and prospects

砾石覆盖是旱区特有的一种保护性耕作模式。长期的农业生产实践已经证明,地表覆砂能够很好地适应旱区严酷、恶劣的自然环境,并为当地农业发展和效益提升带来极大助力。然而,砾石覆盖农田退化所带来的一系列负面效应愈加凸显,成为当地农业发展的障碍因子。文章以砾石覆盖的土壤环境效应为脉络,归纳总结了砾石覆盖对土壤水热环境、土壤盐分、土壤有机质、土壤微生物和酶活性,以及水土保持等方面的影响效应和相关机制。同时,进一步指明旱区砂田当前所面临的问题与挑战,并提出该领域未来可持续深化和拓展的方向,主要包括:(1)砾石覆盖农田退化过程中土壤环境的综合演变机制;(2)“砾石-土壤-作物”系统间的协同作用机制;(3)应对砂田退化的农业修复模式及可持续发展路径;(4)砾石覆盖对局部区域气候的影响机制。

Gravel-sand mulching is a unique conservation tillage mode in arid areas.It has been proved that surface gravel-sand mulching could adapt well to the harsh natural environment,and bring much assistance to local agricultural development and efficiency.However,a series of negative effects were brought by the degradation of gravel-sand mulched field,which had become an obstacle to the development of local agriculture.Therefore,this research summarized the effects and related mechanisms of gravel-sand mulching on soil hydrothermal environment,soil salinity,soil organic matter,soil microorganisms and enzyme activities,as well as soil water conservation.The problems and challenges faced by gravel-sand mulched field were identified,and the directions for further development were proposed,which include(1)the comprehensive evolution mechanism of soil environment in the degradation process of gravel-sand mulched field;(2)the synergistic mechanism of gravel-soil-crop system;(3)the agricultural restoration models and sustainable development paths of degenerated gravel-sand mulched field;(4)the impact mechanism of gravel-sand mulching on local regional climate.