牧草植物篱对紫色土坡耕地水土流失及土壤肥力空间分布的影响  

Effects of forage hedgerows on soil erosion and soil fertility on sloping farmland in the purple soil area

作　　者：林超文[1,2] 庞良玉[3] 陈一兵[3] 黄晶晶[3] 涂仕华[3] 

机构地区：[1]四川农业大学动物科技学院 [2]四川省农业科学院土壤肥料研究所,四川成都610066 [3]四川省农业科学院土壤肥料研究所

出　　处：《生态环境》2008年第4期1630-1635,共6页Ecology and Environmnet

基　　金：国家973计划(2006CB100206);国家科技支撑计划(2006BAD05B06);国际植物营养研究所及四川省科技厅应用基础项目(2008JY0022-1)

摘　　要：植物篱的水土保持效果已得到广泛的认可,并在世界很多地方推广。随着经济植物篱概念的提出,牧草已作为经济植物篱植物得到广泛应用。然而,到目前为止,牧草植物篱对坡耕地土壤肥力的影响规律研究却很少。利用长期定位小区试验,研究了苜蓿(Medicago sativa Linn.)和蓑草(Eulaliopsis binata(Retz.)C.E.Hubb.)植物篱对坡耕地土壤肥力的影响规律,旨在弄清牧草植物篱提高土壤肥力的作用与效果,不断完善植物篱技术。研究发现,坡耕地在建立牧草植物篱后,土壤粘粒在篱前富积,篱下加剧侵蚀,粘粒的富积与侵蚀沿等高线成水平带状分布;土壤有机质、N、P等主要营养元素出现与土壤颗粒相同的分布规律;对K来说,其分布不受植物篱的影响,表现出从坡上向坡下逐渐减少的分布特点。从土壤养分的绝对数量来看,P呈高度富积,而有机质和K则是高度耗竭。因此,坡耕地施肥时可以适当减少P的施用量,增加有机物和K的施用量。针对植物篱带对坡耕地肥力影响的特点,即篱前肥力升高,篱下肥力下降,在坡耕地管理上应特别加强篱下土壤带的培肥,以提高坡面整体生产能力。Effect of plant hedgerows on controlling soil and water losses has been well recognized and thus, this technology has been widely adopted in the world. On the basis of the plant hedgerow, the cash crop hedgerow debuted and was used since late 1990＇s. As the derivative of cash crop hedgerows, the forage plant hedgerow squeezed its way in and has been used in soil conservation ever since. Yet, studies on its effect on soil fertility of sloping lands are rare. Using an eight-year fixed field experiment, the authors investigated the effect of alfalfa （ Medicago sativa Linn. ） hedgerow and Eulaliopsis binata （Retz.） C. E. Hubb. hedgerow against the control treatment on soil fertility. Results showed that clay particles tended to accumulate above the plant hedgerows and to be eroded downward below the hedgerows along contour lines across the field. Distribution of soil organic matter and all plant nutrients except K showed the same pattern as the clay particles. Potassium （K）, however, was evenly distributed in the field without any noticeable influence from the hedgerows. Since the fixed experiment started, soil P has kept accumulating, while soil organic matter and K has been in depletion. The results suggest accordingly better nutrient management practices on the sloping lands by using reduced rates of P and increased rates of farm manure and K. Taking the sloping field as a whole, special attention in nutrient management should be given to the soil stripes - the portions below the plant hedgerows suffering from more serious soil erosion.

关 键 词：牧草 植物篱 土壤侵蚀 土壤养分 空间分布 土壤机械组成 

分 类 号：S158.5[农业科学—土壤学]