中文摘要：

利用1982年河南省第二次土壤普查数据和2009年采样数据，采用传统统计学、地统计学和地理信息系统（GIS）的方法，在土壤系统分类的基础上，揭示河南省不同土类有机质含量时空变异规律，并讨论了影响其变异的主要原因。结果表明：从1982年到2009年，河南省土壤有机质（SOM）含量均值由12．21gkg^-1增加至16．02gkg^-1，增加了31．20％，河南省SOM自西向东逐渐增加，平原地区增加较多，而河南省南部、偏北部和西部山区地区有所减少；系统分类中的底锈干润雏形土、淡色潮湿雏形土、灌淤旱耕人为土、干润冲积新成土、干润砂质新成土、简育湿润变性土、简育湿润雏形土SOM平均含量从1982年到2009年有较大的提高，分别提高了5．7、5．6、5．6、5．5、5．4、5．0、3．1gkg^-1，而湿润正常新成土和干润正常新成土SOM含量有所降低，分别降低了2．5gkg^-1和1．9gkg^-1。因气候条件、成土母质、土壤质地、土地利用方式和人为活动的影响使得河南省不同土类的SOM出现时空差异。

英文摘要：

Soil organic matter （SOM） , as an important source of various nutrient elements in soil, plays a very important role in promoting formation of soil structure, improving soil physical properties and increasing soil nutrient retention capacity. Therefore, based on the second provincial soil survey in 1982 and soil sampling in 2009, and soil classification in line with the soil taxonomy, the paper elaborated regulations of spatio-temporal variation of SOM content in various types of soils in Henan Province, one of the major grain producing provinces of China and analyzed major affecting factors of the variation, with the aid of the techniques of traditional statistics, geostatistics and GIS. Conclusioons of the paper may serve as guidance and reference in implementing rational fertilization and nutrient regulation in Henan Province. The data of 1982 were cited from the Second National Soil Survey. Soil sampling distribution maps of all the cities and counties of the province plotted in the survey were scanned and vectorized, and 1110 typical soil sampling sites were screened out. And the data of 2009 was collected from field sampling, covering a total of 1615 soil sampling sites. The analysis shows that the mean content of SOM increased from 12.21 g kg^-1 in 1982 to 16.02 g kg^-1 in 2009, or by 31.20%, and its coefficient of variation decreased from 67.90% to 35.52%, which indicates that the SOM contents of the two periods were both at a medium level of variation. The variograms of SOM in the two years both fitted the spherical model, with nugget coefficient decreased from 56.10% to 60.18%, and codomain from 569.05 km to 547.22 km, suggesting that the effect of stochastic variability of SOM intensified and spatial autocorrelation weakened. Through referencing between Genetic Soil Classification of China （ GSCC ） and Chinese Soil Taxonomy （CST） , the soils of Henan Province could preliminary be sorted into 6 orders, 12 suborders, 20 groups and 38 subgroups in accordance with the CST. A general trend was o