Evaluation and Classification of Cultivated Land Fertility in Inaccessible Mountainous Areas of Southwest China
YUAN Lei;CHEN Guoping;LUO Yu;School of Information Science and Technology,Yunnan Normal University;Engineering Research Center of Ministry of Education on Geography Information Technology of Western Resource Environment;Geomatics Engineering Faculty,Kunming Metallurgy College;Land Resources Bureau of Huaping County of Yunnan Province;
In order to master the rules of spatial and temporal distribution for the cultivated land fertility in the inaccessible mountainous areas of Southwest China,and to provide a basis for rational fertilization and efficient utilization of regional cultivated land,the paper cites Huaping County as a case study,and 2515 soil samples of cultivated land were randomly collected.Then 13 evaluation factors were selected by using GIS,CART model based on bootstrap algorithm combined with the Fuzzy Mathematics,to evaluate cultivated land fertility classes and spatial distribution.The results showed that the cultivated land fertility in the study area is divided into six classes.Among them,area of the cultivated land of class 3 and class 4 is the largest,accounting for 30.39%and 23.13% for the total areas of the cultivated land respectively,and with the increase of the classes,the irrigated paddy fields area of each class of cultivated land decreased gradually.From the spatial distribution,each class of cultivated land is distributed in each town,but because of the regional topography,soil parent material,soil texture exists spatial difference,the distribution of each class of farmland is a big difference in different towns,then the cultivated land fertility shows the general trend of decaying the radially around the river valley as a center.Besides,the soil fertility declined obviously and the land use limitation increased gradually with the increase of the classes for cultivated land fertility in the county.So,as far as improvement of soil fertility is concerned,the cultivated land of the class 1,class 2,and class 3 should pay attention to scientific fertilization,and deepen the maturing of the soil layer,but the cultivated land of the class4,class 5 and class 6 should focus on the conservation of water and soil.In addition,areas have conditions should also actively to promote engineering of changing mountain slop into terrace field,especially for some cultivated land with much sloping land,the conversion of cropland to forest or grassland may be considered.The evaluation results have important practical significance for analyzing some main obstacle factors of low and middle yield fields,carrying out the directional cultivation of soil fertility and precise management of cultivated land in the similar areas of Southwest China.
【Fund】： 国家自然科学基金(41161062);; 云南师范大学博士科研启动项目(01000205020503063)
【CateGory Index】： F323.211
【CateGory Index】： F323.211