【摘要】 采用野外调查取样和室内试验分析相结合的方法,研究了贵州赤水低山河谷地区典型小流域——赤水市长期镇半山沟小流域内不同土地利用方式下土壤剖面理化性质及其空间变化,结果表明:(1)从空间分布看,耕作层土壤有机质及部分土壤养分出现了下游>上游>中游的现象。(2)不同土地利用方式下,耕作层土壤容重表现为旱地>竹林>树林>水田,土壤孔隙度和田间持水量则表现为水田>树林>竹林>旱地,树林土壤的各种养分含量均高于竹林土壤,水田土壤有机质、全氮、速效氮及全磷、全钾含量均略高于旱地,但有效磷和速效钾含量略低于旱地。(3)从土壤剖面分布看,土壤容重、p H值随土层深度的增加而增加,田间持水量则随土层深度的增加而减少,有机质、全氮、全磷、有效磷含量呈现出从上往下依次递减的趋势,而水田的钾素含量呈现出自上而下先增大后减少的特点。更多还原

【Abstract】 The paper studied the physical and chemical properties of soil profile and its spatial variations under the conditions of different types of land use of Banshangou small watershed in Changqi Town of Chishui City,which is a typical small watershed situated in low mountain valley area of Chishui City in Guizhou Province by using the method of field sampling and laboratory test analysis. The outcomes show that a) viewing from spatial distribution,the soil organic matter and partial soil nutrient of plow layer has the situation of down stream >upper stream >middle stream; b) under the conditions of different land use,the soil bulk density of plow layer shows dry land >bamboo forest >woods >paddy fields and soil porosity and field moisture capacity shows paddy fields >woods >bamboo forest >dry land. The various nutrient contents of woods are all higher than that of bamboo forest soil. The contents of soil organic matter,total nitrogen,available nitrogen,total phosphorus and total potassium are all slightly higher than that of dry land,while the contents of available phosphorus and available potassium are all slightly lower than that of dry land and; c) viewing from soil profile distribution,the soil bulk density and pH value are increased along with the increase of soil depth,the field moisture capacity is decreased along with the increase of soil depth,the contents of soil organic matter,total nitrogen,total phosphorus and available phosphorus show the trend of decreasing from up to down and the content of potassium of paddy fields shows the characteristic of first increase and then decrease from up to down.更多还原