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为了掌握南方丘陵山区耕作土壤养分的时空演变规律，以江西省为例，利用1985年江西省第二次土壤普查数据和2012年测土配方施肥项目采集的大量耕层(0—25 cm)土壤样点数据，借助SPSS经典统计方法、ArcGIS地统计学和半方差分析技术，运用全局空间自相关(Global Moran′s I)和普通克里金(Ordinary Kriging)插值分析相结合的方法，对比分析了近30年耕地土壤全氮(TN)、全磷(TP)、全钾(TK)、有机质(SOM)和酸碱度(pH值)5种养分要素的时空变异特征。结果表明：1985—2012年，江西省耕地土壤养分存在较大的时空差异，2012年土壤养分Moran′s I指数和块金系数较1985年表现为具有较强的空间正相关集聚特性。1985年除土壤pH值符合球状模型外，其余4种养分要素属于指数模型，2012年土壤TN，TP和SOM符合球状模型，TK和pH值符合指数模型，两个时期交叉验证结果均达到显著水平。30年来，研究区耕作土壤养分有升有降，以升为主。土壤TN和SOM处于丰富级水平，其含量显著上升，平均级别分别提升了0.41，0.44个单位；TP处于中等水平，全磷水平上升较为显著，平均级别提升了0.39个单位；TK处于低量级水平，全钾含量急剧下降，平均级别降低了0.89个单位；土壤pH值处于酸性水平，pH值下降较为明显，平均级别降低了0.66个单位。近年来，由于受到人为耕作方式、施肥结构、秸秆还田、工业污染及酸性沉降物等的影响，江西省耕地土壤TN，SOM和TP含量有所提升，TK含量急剧降低，土壤严重酸化。研究结果为江西省土壤养分分区管理、精准高效施肥、土壤养分可持续利用和提升耕地质量提供基础理论和科学依据。
In order to understand the spatial and temporal evolution of soil nutrients in the hilly areas of southern China, taking Jiangxi Province as an example, a large amount of topsoil (0-25 cm) soil collected from the Second Soil Survey of Jiangxi Province in 1985 and the Fertigation Project of Soil Testing and Fertilization Using SPSS classical statistical method, ArcGIS geostatistics and semi-variance analysis technique, this paper uses global Moran’s I method and Ordinary Kriging interpolation method to compare and analyze In the past 30 years, the spatio-temporal variations of five nutrient elements including soil total nitrogen (TN), total phosphorus (TP), total potassium (TK), organic matter (SOM) and pH value were analyzed. The results showed that there was a big spatial and temporal difference in soil nutrients of cultivated land in Jiangxi Province from 1985 to 2012. Moran’s I index and nugget index of soil nutrients in 2012 showed a stronger positive spatial correlation than 1985. In 1985, except the soil pH value which conformed to the spherical model, the other four nutrient elements belonged to the exponential model. In 2012, the soil TN, TP and SOM conformed to the spherical model, and the TK and pH values were consistent with the exponential model. The cross validation results were significant Level. In the past 30 years, the nutrient content of cultivated soils in the study area has been rising and falling to mainly rise. Soil TN and SOM were at rich levels, their contents increased significantly, with an average level of 0.41 and 0.44 units respectively. TP was at medium level and total phosphorus level increased more significantly with an average level of 0.39 units. TK was at low level Level, the total potassium content decreased sharply, the average level decreased by 0.89 units; soil pH value is at the acidic level, the pH value decreased significantly, with an average level of 0.66 units decreased. In recent years, the contents of TN, SOM and TP in arable land of Jiangxi Province have been increased due to the influence of man-made farming methods, fertilization structure, straw returning, industrial pollution and acid sedimentation, etc. The content of TK is drastically reduced and the soil is seriously acidified. The results provide the basic theory and scientific basis for soil nutrient zoning management, precise and efficient fertilization, sustainable use of soil nutrients and improvement of arable land quality in Jiangxi Province.