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.
出处
《草地学报》
CAS
CSCD
北大核心
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
关键词
水蚀风蚀交错带
苜蓿
水流阻力
水容
Wind-water erosion interleaving region
Medicago sativa L.
Hydraulic resistance
Hydraulic capacitance
