土地利用变化对沙地土壤全氮空间分布格局的影响  

Effect of land use change on spatial distribution pattern of soil total nitrogen in Keerqin sandy land

作　　者：陈伏生[1] 曾德慧[1] 陈广生[1,2] 

机构地区：[1]中国科学院沈阳应用生态研究所 [2]中国科学院研究生院,北京100039

出　　处：《应用生态学报》2004年第6期953-957,共5页Chinese Journal of Applied Ecology

基　　金：国家"十五"科技攻关计划项目 ( 2 0 0 2BA5 17A11 5 );中国科学院知识创新工程重要方向项目 (KZCX3 SW 418);内蒙古自治区"十五"科技攻关资助项目 ( 2 0 0 10 10 3 )

摘　　要：利用经典统计学和地统计学相结合的方法 ,分析了科尔沁沙地东南缘草地和 8年前开垦的耕地土壤全氮含量和空间分布格局 .结果表明 ,草地与耕地表层 (0～ 1 0cm)土壤全氮含量差异不显著 ,亚表层(1 0～ 2 0cm)含量差异显著 (P <0 0 5 ) ;耕地土壤全氮贮量比草地高 2 6 2 36kg·hm-2 .草地与耕地比较 ,表层和亚表层土壤全氮的空间分布格局均有明显差异 ,草地土壤全氮的基台值、空间相关度比耕地小 ,而其变程和分数维比耕地大 ;草地土壤全氮水平空间异质性低 ,水平空间分布格局比较均匀 ,而耕地土壤全氮水平空间异质性高 ,水平空间分布格局明显 .草地表层与亚表层土壤全氮含量差异显著 (P <0 0 5 ) ,空间结构特征和空间分布格局差异明显 ,但空间分布格局有较强的相关性 (r =0 395 ,P <0 0 5 ) ;耕地表层与亚表层土壤全氮含量差异不显著 (P <0 0 5 ) ,但空间结构特征有一定的差异 ,而空间分布格局相类似 ,空间相关性极高 (r =0 6 83,P <0 0 1 ) .可见 ,农业活动不仅影响土壤中全氮的含量 ,还影响着其空间结构特征及其水平和垂直空间分布格局 .By using statistics and geostatistics,this paper studied the content and spatial pattern of soil total nitrogen (TN) in a glassland and an arable land of southeast Keerqin sandy land.The TN content in 0～10 cm soil layer of the arable land reclaimed from a glassland 8 years ago was not different from that of the virgin grassland,but the TN content in 10～20 cm soil layer was higher than that in the grassland ( P <0.05).The soil TN storage in the grassland was 262.36 g·hm -2 higher than that in the arable land,and its spatial pattern was significantly different between arable land and grassland.The heterogeneity and spatial dependence of TN in each soil layer (0～10 cm and 10～20 cm) of the arable land were larger than those of the grassland,and the ranges and fractal dimensions of TN in each soil layer of the arable land were larger than those of the grassland.There existed a clear horizontal spatial structure heterogeneity and spatial distribution pattern in the arable land,while in the grassland,the horizontal spatial structure heterogeneity was very low,and the horizontal spatial distribution pattern was random and uniform.The TN content in the 0～10 cm and 10～20 cm soil layers of the arable land had no difference ( P <0.05),its spatial structure characters had some difference ( P <0.05),and its spatial distribution pattern was very similar ( r=0.683,P <0.05).The TN content and its spatial structure characters between two soil layers of the grassland had remarkable difference ( P <0.05),but its spatial distribution pattern in the two layers was relatively similar ( r=0.395,P <0.05).In conclusion,agricultural activity could not only influence soil TN content,but also influence its spatial structure characteristics and spatial distribution pattern.Therefore,our study might promote the further study on the effect of land use change on soil nitrogen distribution pattern and its cycling in ecosystems.

关 键 词：农业活动 土壤全氮 地统计学 科尔沁沙地 空间格局 

分 类 号：X14[环境科学与工程—环境科学]