Abstract:
Based on the quality evaluation of cultivated land in Jilin Province, we studied the distribution of low-grade cultivated land (including seventh, eighth, ninth, tenth grades of lands), and analyzed the conceptual evaluation index and numerical evaluation index of all obstacle factors using the method of classification and summary.The results showed that the area of the lower-grade cultivated land was 1.577 million hectares in Jilin Province, and main obstacles included saline-alkalization, acidification, poor fertility, barrier layers, and gleization.Among them, the area of salt-alkali land was the largest, which accounted for 54.34% of the total and was mainly distributed in Baicheng, Songyuan and other plain regions, with the highest average value of pH(8.34) and the lowlest average value of available phosphorus content(10.1 mg · kg
-1).The area of acidification land accounted for 16.93% of the total, and was mainly distributed in Jilin, Tonghua and mountainous and hilly regions, with the lowest average value of pH(5.21).The barren land accounted for 15.79% of the total, with the lowest average value of organic matter content(17.1 g · kg
-1).The barrier layers land accounted for 11.79% of the total, with the smallest average value of soil layer thickness (49 cm).The gleized land accounted for 0.89% of the total, with the highest average value of organic matter content (36.4 g · kg
-1).