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作 者:傅伯杰[1] 郭旭东[1] 陈利顶[1] 马克明[1] 李俊然[1]
机构地区:[1]中国科学院生态环境研究中心系统生态开放研究实验室,北京100085
出 处:《生态学报》2001年第6期926-931,共6页Acta Ecologica Sinica
基 金:国家自然科学重点基金!(批准号 4 983 1 0 2 0 );中国科学院知识创新基金!( KZCX2 -4 0 5)
摘 要:土地利用变化可以引起土壤养分的变化。以河北省遵化县为例 ,研究该县 1 980年到 1 999年土地利用变化及土壤养分的变化。结果表明 ,近 2 0 a来 ,旱地、草地、水田面积大幅度减少 ,林地和村镇用地大幅度增加。旱地转换为林地 ,土壤有机质提高了 2 1 % ,全氮提高了 1 0 % ,碱解氮提高了 65% ,速效磷提高了 1 7% ,速效钾提高了 1 7%。旱地转换为草地 ,土壤有机质提高 3 8% ,全氮提高了 3 7% ,碱解氮提高了 71 % ,速效磷提高了 2 % ,速效钾提高了 2 8%。退耕还林还草不仅改变了土地覆被 ,而且提高了土壤养分。Land use Change is the results of interactions between physical factors and human activities.Land ues change may influence many natural phenomena and ecological processes,including soil nutrient and soil water change,runoff and soil erosion,biodiversity and biogeochemical cycle.Land use changes can results in land degradation,such as water and soil loss,land desertification.It also can control water and soil loss,land desertification,and improve soil quality.Since late 1970s,the new land policy “Household Responsibility System” was implemented in the Chinese countryside,which has advanced China's agriculture and led to great changes in land use structure.Land use change has resulted in some changes in soil nutrients.This paper took Zunhua County,a typical agricultural area in northern China as a case study to analyze the relationship between land use changes and soil nutrient changes.The objectives are (1)to identify land use change within two typical periods of 1980 and 1999.(2)to examine soil nutrient changes between 1980 and 1999,and (3)to analyze the relationships between land use changes and soil nutrient changes. Land use change from 1980 to 1999 shows:(1)the area of farmland,grassland and paddy field decreased by 40%~50%;(2)the areas of forest,residential land,and water field increased by over 60%;(3)unutilized land had been transformed to farmland,forest,and residential land.The results of a transition matrix reflected the area increase or decline of each land use type.Between 1980 and 1999,29%,10%,and 10% of cultivated farmland were converted to forest,residential land and grassland respectively.About 64% of grassland was transformed to forest.About 59% of unutilized land was transformed to grassland,and 31% was transformed to forest. The soil nutrient status of farmland in 1999 increased significantly( p <0.10%)compared to 1980.The increase in organic matter content was because of an increase in straw incorporation.The differences in organic matter content for forest between 1980 and 1999 we
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