农田土壤肥力质量演化及其与景观特征的关系

通过GPS定位采集样品，标准方法的土壤化验，应用GIS空间分析技术，揭示农田土壤肥力质量的演化特征，分析景观特征对土壤肥力质量演化的影响。研究结果表明：研究区域潴育型水稻土的肥力质量指数最高，侧渗型水稻土肥力质量指数最低。20年来，研究区域农田土壤肥力质量指数有84.4%的面积是上升的，指数升幅主要在0~0.2之间，面积为498km2，占总面积的73.2%；研究区只有15.6%的面积是下降的，其中以降幅在0~0.2之间的面积最大，为73km2，占总面积的10.7%。从空间分布上看，研究区中部、西南和北部的农田土壤肥力质量较高，而东南和北部的部分地区较低。景观特征对土壤肥力质量的演化有很大影响，20年来土壤肥力质量上升的，主要分布在千枚岩、花岗岩和红砂岩发育的土壤中，土壤类型为潴育型水稻土，海拔在800m以下。

Variation of Soil Fertility Quality with Landscape Characteristic in Farmland

Soil samples were collected with GPS reference locations and analyzed using standard methods. Characteristics of variation of farmland soil fertility quality was revealed using a GIS spatial analysis technique; Relations of soil fertility quality and its indices with landscape characteristics were discussed. Results of the soil fertility evaluation show that the soil fertility quality was not high in the studies area in 2001 with an index distribution pattern of being lower in the southern part than in the central, western and northern parts. Over the past 20 years, the general trend of the change in soil fertility quality appeared to be upward. The area of farmland with improved soil fertility quality was accounted for 84.4% of the total in the studied zone. The index up between 0 and 0.2 occupying the largest area (498 km2),73.2% of total farmland area; The area of farmland with dropped soil fertility quality was accounted for 15.6% of the total in the studied zone. The index drop between 0 and 0.2 occupying the smallest area (73 km2),10.7% of total farmland area. Landscape characteristic has a great influence on soil fertility quality evaluation. Over the past 20 years, the change in soil fertility quality appeared to be upward was in Anthrosols derived from phyllite, granite and red sandstone, with an elevation below 800m.