摘要
该文首先进行了县域耕地样地法评价的方案设计,该方法的核心是在耕地质量分计算中,将评价单元的特征与设置与评价区域内的标准样地进行对比后完成的.然后应用样地法将河南省南阳市卧龙区的耕地评价为Ⅰ～Ⅷ等.Ⅰ～Ⅲ等的耕地中,有87.6%的面积分布在冲积、湖积平原区;Ⅳ～Ⅵ等耕地中,有61.4%的面积分布在垄岗区;而Ⅶ、Ⅶ等耕地集中分布在丘陵区.样地法所划分耕地等别的分布在总体上合理地体现了不同地貌类型及土壤条件下耕地质量的差异.利用210个样点单元的标准粮产量与其对应样地法耕地质量分进行线性拟合,判定系数等于0.876的含义是指标准粮产量的变异中有87.6%是由耕地质量分引起.样地法耕地质量分的高低较好地反映了耕地的生物生产力水平.所以,所设计的样地法可为中国县域样地法耕地评价提供方法与模式参照.
This paper dealed with the design of reference land unit method of arable land evaluation at county level. The core of this method WAs the calculation of arable land quality ratings by comparing the characteristics of the arable land evaluation unit and reference land unit in an area. The method was applied to evaluate the arable land at county level in Wolong district, Nanyang city, Henan province. Where the land was classified into 8 grades（grade Ⅰ to grade Ⅷ）. 87.6% of the land from grade Ⅰ to grade Ⅲ distribute on alluvial and lacustrine plains. 61.4% of them from grade Ⅳ to grade Ⅵ distribute on slightly rolling parts. Grade Ⅶ and grade Ⅷ are concentrated at the foothills. The results showed that the spatial distributions of the different grades of the arable land, classified by the reference land unit method, reflected reasonably the spatial changes of geomorphological units and soil types. The linear estimation model between comparable productions and the corresponding quality ratings of 210 sample units showed＇that the coefficient of determination R2 is 0. 876, which meant that 87.6% of the change of standart grain yield output is explained by the change of quality score of arable land. It is concluded that the arable land quality ratings calculated by the method can reflect the biologic productivities of land. Therefore, the reference land unit method designed can provide as a reference method or model for other places in China, when the arable land evaluation to be conducted.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2005年第11期54-59,共6页
Transactions of the Chinese Society of Agricultural Engineering
关键词
耕地
标准样地
样地法
arable land
reference land unit
reference land unit method
