摘要
将数字化好的秦安县土壤图、土地利用现状图、行政区划图叠加求交生成耕地资源评价单元,并分别对评价单元数据层中实体面积小于7 000、15 000m2的小多边形进行合并及不合并多边形,从而对三种不同的小多边形合并方法产生的评价单元分别进行耕地地力评价结果比较。结果表明:以实体面积小于15 000 m2合并多边形得到的评价单元,由于评价单元面积较大,致使地貌类型作为评价因子的贡献率较小,从而影响评价结果,导致评价结果与实际情况存在较大差异;不合并多边形得到的评价单元,由于评价单元过小,定点测到的数据空间插值后不能具体到很小面积的区域上,从而影响评价结果。结论:地貌类型作为重要的参评因子及研究区域地域面积大小共同决定评价单元面积的大小。
The cultivated land resource evaluation units in Qin＇an were generated by integrating the digital soil map,present landuse map and administrative map,with merging and not merging small polygons less than 7 000 m2 and 15 000 m2 of the evaluation unit data layer respectively,and the evaluation results of cultivated land fertility were compared of the evaluation units produced by merging small polygon with three different methods.The results show that for the evaluation unit through merging polygon less than 15 000 m2,the evaluation unit area is large and the contribution rate of the physiognomy types as evaluation factors is small,which impacted the evaluation results and lead to great difference between evaluation result and the actual situation;Because the area of the evaluation units without merging polygon is too small,the designated measuring for data space interpolation can＇t specific to a very small area,thereby affecting the evaluation results.The conclusion is： the landscape as an important factor and the size of regional area decides the size of the area of evaluation unit.
出处
《干旱地区农业研究》
CSCD
北大核心
2012年第4期224-230,共7页
Agricultural Research in the Arid Areas
基金
甘肃省科技支撑计划(1104NKCA093)
