不同生育期土壤-苜蓿系统水流阻力和水容变化规律研究  

Dynamical Changes of Hydraulic Resistance and Capacitance in the Soil-alfalfa System at Different Growth Stages

作　　者：付微[1,2] 黄明斌[1] 邵明安[1] 

机构地区：[1]中国科学院水利部水土保持研究所,黄土高原土壤侵蚀与旱地农业国家重点实验室,西北农林科技大学,陕西杨凌712100 [2]中国科学院研究生院,北京100049

出　　处：《草地学报》2009年第5期575-580,共6页Acta Agrestia Sinica

基　　金：国家“973计划”项目(2007CB407201);中国科学院、国家外国专家局创新团队国际合作伙伴计划-流域水土过程模拟

摘　　要：紫花苜蓿是水蚀风蚀交错带重要的人工种植牧草,具有较强的耐寒、耐旱性。自然条件下的模拟土柱试验在陕北神木试验站进行,采用抑制蒸腾法定量分析了水蚀风蚀交错带土壤-苜蓿系统水流阻力、水容等瞬态水流参数变化过程。结果表明:不同生育期内瞬态水流阻力及水容有明显差异:开花旺盛期平均水流阻力最小0.22×108Mpa.s.m-3,约为干枯老化期的1/9;平均水容最大5.38×10-4m3/Mpa;是现蕾期的4倍多。该研究结果有助于揭示紫花苜蓿体内水分调节作用及抗旱机制,对干旱半干旱地区植被恢复有重要指导意义。Alfalfa（Medicago Sativa L.） is one of the dominant sown forages with the characteristics of strong tolerance to cold and drought in the interleaving region of wind and water erosions of the Loess Plateau.A simulating experiment of alfalfa planted in soil columns with different water treatments was conducted under the natural conditions at Shenmu Experimental Station,Shaanxi province and the dynamical changes of hydraulic resistance and capacity in the soil-alfalfa system was quantitatively calculated using transient water flow model of the transpiration-preventing method.The results show that hydraulic resistance and capacitance varied with growing seasons.The mean hydraulic resistance at flowering stage was minimum at 0.22×108 Mpa.s.m-3,which was about 1/9 lower than that at senescent stage,and the mean hydraulic capacitance was maximum at 5.38×10-4 m3/Mpa,which was four times higher than that at squaring stage.The results could help further understand the mechanism of water regulation and drought resistance of alfalfa and be useful for revegetation practice in the arid and semi-arid areas.

关 键 词：水蚀风蚀交错带 苜蓿 水流阻力 水容 

分 类 号：Q948.118[生物学—植物学]