摘要
按8km×8km网格将聊城市耕地分为136个采样点,调查土壤有机质、全氮、全磷、全钾4种土壤养分的含量。采用地统计分析与空间自相关的MoranI系数分析土壤养分的空间变异规律。研究表明,土壤耕层养分含量变化的空间异质性主要由随机性因素如灌溉、施肥、耕作措施、种植制度等人为活动引起,空间相关性很弱。4种土壤养分存在明显的空间分布规律,总体上呈现由东、南部向西、北部逐渐递减的空间分布格局。在40km范围内,4种土壤养分的MoranI系数均为正值,表现出在此范围内空间呈正相关。有机质对尺度的响应较其他3种养分更为敏感,全氮和全磷的MoranI变化趋势类似,而全钾在64km范围之外的MoranI系数表现出在0值附近的波动性,可能与地方农业活动有关。
Based on data from field sun＇ey of arable soil by the end of 2008, spatial heterogeneity and distribution patterns of soil nutrients in Liaocheng City, Shandong Province were studied in this paper. By 8 km×8 km grid, the land was divided into 136 sampling points, and the contents of soil organic matter, total N, total P and total K were monitored. The combination of GIS, spatial autocorrelation analysis and geostatistical analysis was used to analyze the spatial features of soil nutrients. Traditional statistical analysis shows that, after decades of farming, the variation of soil nutrient content in the measurement scale has the increasing trend.Geostatistical analysis shows that, the changes of spatial heterogeneity of four kinds of soil nutrient are not identical in the entire region. The changes of organic matter and total N are irregular, while the spatial variability of total P is more random. The spatial heterogeneities of soil nutrients change mainly by random factors. Human activities, such as irrigation, fertilization, cultivation measures, cropping systems, etc, are major factors. The spatial correlations of four soil nutrients are very weak. On the whole, there is an obvious spatial distribution of the four soil nutrients which gradually declines from the eastern and southern to the western and northern part of Liaocheng City. Spatial autocorrelation analysis shows that, as the scale increases, spatial autocorrelation decreasing trends of four soil nutrients are similar, but the overall response on the scale is hardly evident. In the scope of the 40 km, Moran＇s Icoefficients of four kinds of soil nutrients are positive which shows a positive spatial correlation. The response of organic matter on the scale is more sensitive than that of other three nutrients. The change of Moran＇s l of total N and total P is similar. But Moran＇s I coefficient of total K outside the scope of 64 km performs the volatility in the vicinity of 0, which may be related to the local agricultural activities.
出处
《科技导报》
CAS
CSCD
北大核心
2009年第23期49-52,共4页
Science & Technology Review
基金
山东省优秀中青年科学家科研奖励基金项目(2007BS08026)
关键词
空间异质性
土壤养分
地统计分析
空间自相关分析
spatial heterogeneity
soil nutrients
geostatistics analysis
spatial autocorrelation analysis
