陕北农牧交错带土地资源质量评价

Evaluation on the land resource quality of the cross area of agriculture and ranch in Northern Shaanxi

以年均降水量、≥10℃积温、年均气温、平均日照时数和无霜期为气候因素指标,海拔高度和地貌类型为地貌因素指标,土壤质地、土壤碱解氮、土壤速效钾、土壤速效磷、土壤全氮和土壤有机质为土壤因素指标,用层次分析法分析评价陕北农牧交错带土地资源质量。结果表明:气候状况从东南向西北逐渐变差,佳县的气候最好,靖边气候条件最差;土壤以长城为界,长城以北质量较差,长城以南逐渐变好;一二级地面积较少,约238 km2,占研究区总面积的0.7%,三级地4 143 km2,占11.4%,四级地10 997 km2,占30.4%,五级地9 254 km2,占25.6%,六级地8 105 km2,占22.4%,七级地3 372 km2,占9.3%;一二级地主要为分布在窟野河、秃尾河、佳芦河和榆溪河流域的滩地和河川地,三四级地主要分布于黄土丘陵沟壑区的塬梁地、峁地以及沟道,五级地主要为分布于黄土丘陵区域的梁地,少量是长城沿线的固定沙地,六七级地则主要是位于长城沿线的沙丘、半固定沙地和固定沙地。

Land resource quality in the cross area of agriculture and ranch in northern Shaanxi was evaluated using APH （Analytic Hierarchy Process） method, in which climate factors included annual average precipitation, ≥ 10℃ accumulate temperature, annual average temperature, average sunshine time, and time without frost, landform factors included altitude and landform type, soil factor include soil texture, soil alkali N, soil quick-acting K, soil quick-acting P, soil total N, soil organic matter. The results show that： the climate conditions on the research region were changing worse from southeast to northwest,, climate in Jiaxian is the ：best, in Jinbbian is the worst; soil on the north Great wall is bad, soil on the south Great wall changes better; evaluating on the total, first and second grade land were less, 238 km^2 which accounts for 0.7% of the research area, third grade land 4 143 km^2 accounts for 11.4%, fourth grade land 10 997 km^2 accounts for 30.4%, fifth grade land 9 254 km^2 accounts for 25.6 %, sixth grade land 8 105 km^2 accounts for 22.4 %, seventh grade land 3 372 km^2 accounts for 9.3 % ; first and second grade land are mainly distributed on the bank and shoals alone the river Kuye, Tuwei, Jialu, and Yuxi, third and fourth grade land are mainly distributed ridge, tableland and hill of loss plateau, and river bank, fifth grade land is distributed in the ridge of loss plateau and fixed sand area alone the great wall, sixth and seventh grade land are located in sand hill, semi-fixed sand and fixed sand areas.