Abstract:
The study aimed to reveal the spatial and temporal evolution characteristics of cultivated land soil quality in Shantou City, identify the core problems such as soil nutrient imbalance and acidification of cultivated land, and provide reference for the regional cultivated land quality improvement and comprehensive management. Based on the monitoring data of 9 representative cultivated land quality monitoring points in Shantou City from 2011 to 2020, the spatial and temporal evolution of soil organic matter, total nitrogen, available phosphorus, available potassium and pH value were systematically analyzed by using the inter-annual variation data statistics and GIS spatial analysis technology. The results showed that the average soil organic matter content of cultivated land in Shantou increased from 21.95 g·kg
−1 to 28.67 g·kg
−1 in 2011−2020, an increase of 30.62%. The soil pH value was weakly acidic as a whole, and the average value remained at 4.80~6.01 during the 10 years. The overall change was not significant, but the acidification trend was obvious in some areas. The average total nitrogen content increased from 1.28 g·kg
−1 to 1.53 g·kg
−1, an increase of 19.53%. The average content of available potassium increased from 75.11 mg·kg
−1 to 108.22 mg·kg
−1, an increase of 44.08%. The soil available phosphorus content was in a state of high fluctuation for a long time, and the average value was maintained at 30.94~78.97 mg·kg
−1, which was much higher than the appropriate level, and there was a problem of excessive accumulation. Based on this, the management model of cultivated land fertilization by zoning and classification was proposed, that was, on the basis of improving organic matter in the whole region, the effective phosphorus reduction and storage control and local acidification treatment should be promoted, the fertilization structure should be optimized, and the long-term monitoring network should be improved, thus to support the dynamic management and precise regulation of cultivated land quality.