我国东南丘陵山区土壤肥力的综合评价

COMPREHENSIVE EVALUATION OF SOIL FERTILITY IN THE HILLY AND MOUNTAINOUS REGION OF SOUTHEASTERN CHINA

土壤肥力是土壤的养分状况以及土壤在供应植物生理所需物质时所处的环境条件这两者的有机结合，本文根据模糊（Ｆｕｚｚｙ）数学和多元数理统计分析原理，建立了一个定量的土壤肥力综合评价方法。首先，利用我国东南丘陵山区的第二次全国土壤普查资料，选取了１１项评价指标，分成两组，并根据其植物效应建立了两类隶属度函数（Ｓ型和抛物线型），分别计算了隶属度值。然后，利用统计分析软件ＳＴＡＴＧＲＡＰＨＩＣＳ进行因子分析，确定各因子的权重。最后，根据加乘法则，求出土壤肥力的综合性评价指标值（ＩＦＩ，ＩｎｔｅｇｒａｔｅｄＦｅｒｔｉｌｉｔｙＩｎｄｅｘ）。根据评价结果，采用地理信息系统（ＧＩＳ）软件ＩＬＷＩＳ绘制了东南丘陵区土壤肥力状况图。从土壤肥力水平与该区粮食、水果产量水平进行比较中，我们找出了存在差距的地区以及引起这些差距的主要因子。结果表明，这一地区土壤肥力大多处于中下水平，高、中、低肥力土壤的面积比例分别为２５．９％、４０．８％和３３．３％。内陆腹地，特别是土壤肥力较高的安徽沿江平原、鄱阳湖平原、湘西武陵山区和广西的河池等地区，土壤肥力资源尚有较大潜力待进一步挖掘，限制本区土壤肥力资源潜力发挥的两个主要因子是土壤侵蚀严重和投入水?

An evaluation method of soil integrated fertility was developed and used forevaluating soil fertility in the hilly and mountainous region of Southeastern China,with soil fertility being considered as a complex of the state of soil nutrients andthe capacity to regulate and transform the materials needed by plants.With systematic principle and the data of the Second National Soil GeneralSurvey, 11 indexes were divided into two groups representing, separately, states ofsoil nutrients and environments of nutrient supplying, involving content of soil or-ganic matter, total N, total P_2O_5, total K_2O, available P_2O_5, available K_2O,pH,CEC, physical clay, silt-clay ratio and thickness of epipedon. Then two types ofmembership functions of these indexes, S-type and parabola-type, were developedbased on their effects on plants. Their values of function were also calculated. Through factor analysis of these values with software STATGRAPHICS, weight va-lues of these indexes weredecided. Finally, IFI (Integrated Fertility Index) of dif-ferent soils was calculated according to addition-inultiplication principle. With GIS software ILWIS, the map of soil coinprehensive fertility in Southe-astern China was drawn. The soil fertility in this region was mainly middle andlow, and soils with high, middle and low fertility amount to 25.8%, 40.8% and33.3% respectively. The regions which had great potentiality in soil fertility oftenhave high soil fertility, such as Anhui plain along the Yangtse River, the PoyangLake plain, Wuling Mountain area in the western Hunan and Hechi region in Gu-angxi. Two principal reasons affecting the full utilization of soil fertility were lowinput and serious erosion.