| China has more people but less land.With the decline of Cultivated land per capita,the quality of farmland resources has been received more attention.This study refers to the"Farmland Grading"and uses the factor method to evaluate the quality of cultivated land in Yunxi District in 2013 and 2019,and analyzes the spatial-temporal changes of cultivated land quality;according to the Ecology theory,there are seven landscape pattern indexes,including patch density,boundary density,landscape shape index,average patch size,spread index,landscape separation index and Shannon diversity index,were used to analyze the change characteristics of cultivated land landscape pattern in 6 years.The following research conclusions were obtained:Compared with 2013,the total cultivated land in Yunxi District increased by a net139.29 hectares in 2019.Weighted by area,the average National Natural grade of cultivated land in Yunxi District in 2019 is 3.9 grade,increased by 0.06 grade;the average utilization grade is 5.77 grade,increased by 0.05 grade,Among these two indicators,the one that improved the most was Yongji Town;the average economic grade is 9.35 grade,increased by0.01 grade,and place where is increased most is Lucheng Town,increased by 0.03.During the6 years,the increase ranking is National nature grade,National utilization grade and National economy grade.Through the land consolidation and increase and decrease linked projects,the quantity of cultivated land has been guaranteed,the production conditions of cultivated land have been greatly improved,and the quality of cultivated land has been improved.In this study,the number of patches and patch density of cultivated land of different quality has been increased,the level 9 utilization grade has been increased most,increasing by 18.54 patches/km~2;the landscape shape index has been increased,the level 2 nature grade has been increasde most,increasing by 16.78;the boundary density has been increased,the level 2 utilization grade has been increasde most,increasding by 194.89 m/hm~2;the average patch area has been decreased,the level 3 nature grade has been decreased most,decreasing by 0.82 hm~2.In Yunxi District,due to the large amount of newly developed arable land,the patch connectivity became worse,the fragmentation degree became higher,and the patch shape became more complexFinally,it puts forward some suggestions and countermeasures,such as strengthening the centralized management of cultivated land,strictly implementing the balance system of occupation and compensation of cultivated land,and continuing reasonable fertilization to improve soil quality,so as to improve the degree of contiguous cultivated land and enhance the efficiency of cultivated land utilization. |
