中文摘要：

农用地自然质量等级划分是农用地分等的前提和基础，其划分合理与否直接关系到农用地分等能否川页利进行，但现有研究方法难以全面反映农用地自然质量的差异性及其性质的可变性。依据浙江省的地形地貌等自然条件差异，将其划分为六大区域，并选择性地构建了不同的农用地自然质量等级划分的因素指标（基础肥力、土壤质地、有机质、耕层厚度、灌溉、排涝、pH、地下水位、坡度等）和评分标准，在此基础上基于可拓理论建立了农用地自然质量等级划分的可拓评价模型，并运用模型对水稻、小麦和油菜作物分别进行可拓评价及多作物综合分等，最终得到浙江省农用地自然质量分等结果。研究表明，可拓评价方法能反映农用地自然质量等级的动态性和可变性，使评价更为精细化和客观化，结果更符合浙江省农用地实际情况。

英文摘要：

Division of natural quality is quite important to farmland classification. However, previous studies are difficult to fully reflect the difference and variability of farmland＇s natural quality. Therefore, taking Zhejiang province as an example, this paper put forward six indexes and its evaluation criteria for natural quality of farmland classification according to the environmental difference. And then, by introducing extension method, it established a new model of natural quality of farmland classification and applied it on three crops including rice, wheat and rape. Finally, the result of farmland classification was generated. Results showed that this model is not only valid for natural quality of farmland grading, but also will help improve the objectivity in farmland classification.