基于GIS的青海省湟源县耕地地力评价研究

为了探索在高原区的耕地地力评价方法,在GIS的支持下,通过土壤图和土地利用现状图叠加的方法来划分评价单元,采用特尔斐法选立地条件、气候、土壤理化性质、土壤管理等4个方面的10个因子建立评价指标,运用层次分析法和模糊数学方法对耕地地力进行综合评价,并就其影响评价结果准确性的因素进行了分析。结果表明:在高原条件下,由于土壤单元比较零散,相邻地块的高程变化有可能很大,评价单元的插值方法非常关键,分土类用反距离加权法插值精度最高,是在山地条件下的单元图土壤养分赋值值得推广的一种方法。将初次评价结果进行检验,进而对评价因子做出修正,然后再次评价是提高评价准确性的有效手段。

Evaluation of the farmland productivity of Huangyuan County of Qinghai province based on GISEvaluation of the farmland productivity of Huangyuan County of Qinghai province based on GIS

In order to study the cultivated land fertility evaluation method in the plateau area, under the support of GIS, the evaluation unit is divided using soil distribution map and introducing overlap method of land utilization map. Four aspects, i.e. land growing situation,climate,physic-chemistry condition and land management are selected using the Delphi method, and 10 factors are used to es- tablish the evaluation indicator system. The comprehensive evaluation on cultivated land fertility is made using analytic hierarchy process analysis and fuzzy mathematics method, and the factors affect- ing the accuracy of evaluation results are analyzed. The results show that ： （ 1 ） in the plateau condi- tion, the elevation difference of adjacent plots may be large due to the soil unit fragmentation, there- fore interpolation method of the evaluation unit is key. The inverse distance weighted interpolation has high accuracy and need to be extended map soil nutrient element in mountainous conditions. （2） the initial evaluation results are tested, and then make a correction to the evaluation factors, and then evaluating is an effective means to improve the assessment accuracy.