乡镇尺度农田土壤养分时空变异性研究.

Based on the soil data of four periods in 1982 (the second soil census), 1998, 2008, and 2018, geostatistic and Kriging interpolation methods were used to analyze the spatio-temporal variation characteristics of topsoil organic matter (SOM), total nitrogen (TN), available potassium (AK), and available phosphorus (AP) in Zong′ ai Town of Shouyang County, Shanxi Province. Combined with the center of gravity model, the center of gravity migration direction of nutrients was explored, and the spatio-temporal variation patterns of the soil nutrients and their influencing factors were revealed during the period of 1982—2018 in Zong′ ai Township. The results showed that the average contents of soil SOM, TN and AP, AK increased by by 3.30, 0.19 g·kg-1 and 7.75, 53.13 mg·kg-1, with the increase rate of 26.92%, 26.39%, 131.80% and 70.31%, respectively, from 1982 to 2018. SOM and AP contents showed an increase-decrease-increase trend from 1982 to 2018, while AK and TN contents kept increasing. Compared with 1982, the block-base ratios of SOM, TN, AP, and AK increased in 2018, indicating that the nutrients of the four periods of time were jointly influenced by structural and non-structural factors (random factors) and the degree of influence by non-structural factors gradually increased, and the influence of anthropogenic activity interference became more significant. In 2018, the spatial distribution characteristics of SOM contents in the study area showed a pattern [ABSTRACT FROM AUTHOR]