【作者】 侯洁；

【导师】 张世熔；

【作者基本信息】 四川农业大学 ， 土壤学， 2010， 硕士

【摘要】 根据射洪县表面土壤有机碳密度资料,结合该区域内地貌特征,基于SPSS13.0及ArcGIS9.2平台,运用常规统计及地统计学方法研究了射洪县内小、中、大3种尺度下土壤有机碳密度基本统计特征、空间变异特征和相关影响因素分析。研究结果分述如下。小尺度下低丘、中丘和高丘三种样区的土壤有机碳密度均值分别为4.26 kg m-2、4.03 kg m-2和3.56 kg m-2,且两两间呈显著差异(P=0.011)；但同种地貌不同地貌单元间土壤有机碳密度差异不显著(P>0.05)。各地貌单元空间变异最优拟合模型以高斯及指数模型为主。块金值与基台值比值介于0.211-0.915之间,其中除Ls1、Ls2、Hs4、Hs5地貌单元空间变异以结构性变异为主(0.211-0.471)外,其余地貌单元均以随机性变异为主(0.535-0.915)。各地貌单元分维值在1.769-1.99995之间,其中低丘各地貌单元样本间变异程度总体大于中丘及高丘,后两种地貌间差别不大。低丘个地貌单元土壤有机碳密度主要集中在3.5-4.5 kg m-2密度级,高丘主要集中在3.0-4.0kg m-2密度级,而中丘主要密度级介于两者之间。中尺度下低丘、中丘和高丘三种样区的土壤有机碳密度均值分别为3.61 kg m-2,3.56kg m-2和3.30kg m-2,且两两间呈极显著差异(P=0.000)。进一步对同种地貌下不同样区间进行比较,结果为低丘区各样区间差异显著(P=0.050),高丘区各样区间差异极显著(P=0.000)。中尺度各地貌样区空间变异最优拟合模型以高斯及指数模型为主。块金值与基台值比值介于0.499-0.971之间,其中除低丘Lm3区以结构性变异为主外,其余样区以随机性变异为主。各样区分维值在1.740-1.996之间,样区间所体现的变异程度差别不大。各地貌样区间土壤有机碳密度均主要集中在相对中低级别(<4.0 kg m-2)大尺度土壤有机碳密度均值为3.37kg m-2。块基比为0.981,分维值1.9956,表明空间变异为随机变异主导。土壤有机碳密度主要集中于<4.0kg m-2密度级,所占比例为89.93%。三种尺度下成土母质、土壤类型、土地利用类型对土壤有机碳密度空间分布的影响程度有所不同。在小尺度下母质、土壤类型、土地利用方式均极显著影响土壤有机碳密度(P=0.000)。其中土壤有机碳密度表现为泥岩极显著高于砂泥岩(P=0.000),后者极显著高于粉砂岩(P=0.007)；冲积物除显著高于粉砂岩外(P=0.013),与其余2种成土母质间差异不显著(P>0.05)。不同土壤类型有机碳密度比较为水稻土显著高于新积土(P=0.015),极显著高于紫色土(P=0.000),并且后两者之间差异不显著(P>0.05)；黄壤分别与其余3种土壤类型间差异不显著(P>0.05)。不同土地利用方式下土壤有机碳密度为水田显著高于林地(P=0.038),后者又极显著高于旱地(P=0.000)。在中尺度下母质、土壤类型均极显著影响土壤有机碳密度(P=0.000),土地利用方式显著影响土壤有机碳密度(P=0.017)。其中土壤有机碳密度表现为冲积物、泥岩、砂泥岩分别极显著高于粉砂岩(P=0.000)；泥岩极显著高于冲积物(P=0.000),后者又极显著高于砂泥岩(P=0.001)。不同土壤类型有机碳密度为水稻土极显著高于新积土和黄壤(P=0.000),且后二者间差异不显著(P>0.05),但它们又极显著高于紫色土(P<0.01)。不同土地利用方式下土壤有机碳密度为水田显著高于旱地(P=0.046),极显著高于林地(P=0.005),但旱地与林地差异不显著(P>0.05)。在大尺度下母质、土壤类型均极显著影响土壤有机碳密度(P=0.000),土地利用方式显著影响土壤有机碳密度(P=0.036)。其中不同成土母质土壤有机碳密度比较为泥岩>冲积物>砂泥岩>粉砂岩,且两两间呈极显著差异(P=0.000)。不同土壤类型有机碳密度为水稻土分别极显著高于黄壤、新积土(P=0.000),且后两者间差异不显著(P>0.05),但它们又极显著高于紫色土(P=0.000)。不同土地利用方式下土壤有机碳密度为水田、旱地分别显著高于林地(P=0.041,P=0.044),水田与旱地间差异不显著(P>0.05)。更多还原

【Abstract】 According to the SOCD data in the surface of the soil and landform characteristices in Shehong,based on SPSS 13.0 and ArcGIS9.2,using general statistical method and geo-statistics,study on statistical,spatial variation characters and the influence factors of SOCD in microscale,mesoscale and macroscale. The results of the study are as follows.The mean of SOCD of low hilly,medium hilly and high hilly in microscale were 4.26 kg m-2,4.03 kg m-2,3.56 kg m-2,and there were significant differences of between different landforms(P=0.011);there were no significant differences between each region in the same landforms(P>0.05).The most fitting models were gaussian model and exponential model in different landforms.The ratio of nugget and sill were between 0.211 to 0.915;it showed that the spatial variation characters of the regions in different lanforms were most of randomness variation,but excepet Ls1,Ls2,Hs4 and Hs5.The fragmentation D was between 1.769 to 1.99995,it showed that the spatial variation extent of most regions were similar.The density classes of SOCD were centralizing in 3.5-4.5 kg m-2 in low hilly, between 3.0-4.0 kg m-2 in high hilly, and the medium was between low hilly and high hilly.The mean of SOCD of low hilly,medium hilly and high hilly in mesoscale was 3.61 kg m-2,3.56 kg m-2,3.30 kg m-2.and there were significant differences of between different landforms(P=0.000).There were significant differences between each region in low hilly(P=0.050),extremely significant differences between each region in high hilly(P =0.000).The most fitting models were gaussian model and exponential model in different landforms.The ratio of nugget and sill were between 0.499 to 0.971;it showed that the spatial variation characters of the regions in different lanforms were most of randomness variation,but excepet Lm3.The fragmentation D was between 1.740 to 1.966,it showed that spatial variation extent of most regions were similar. The density classes of SOCD were centralizing in<4.0 kg m-2 kg m-2 in different landforms.The mean of SOCD of macroscale was 3.37kg m-2.The ratio of nugget and sill was 0.981,fragmentation D wasl.9956,this showed that the spatial correlation was most of randomness variation.The density classes of SOCD were centralizing in <4.0 kg m-2 kg m-2,and the ratio was 89.93%. The influence degree of parent materials,soil types and land-use types for SOCD characters in microscale,mesoscale and macroscale were different.Parent materials,soil types and land-use types had extremely significant influence on SOCD in microscale. The comparison result of SOCD showed that mudstone was extremely significant higher than sandshale(P=0.000), and the later and siltstone had extremely significant(P=0.007);the alluvium was significant higher than siltstone(P=0.013),but had no significant difference with other parent materials(P>0.05). The comparison result of SOCD of different soil types showed that the paddy soil was significant higher than fluvo-aquie soil (P=0.015),extremely significant higher than purple soil (P=0.000),and the two laters had no significant;yellow soil and other three soil types had no significant difference(P>0.05).Comparison result of SOCD in different land-use types showed that the paddy field and forest land were separately extremely significant higher than dry land(P=0.000), paddy field was significant higher than than forest land(P=0.038),and the later was extremely significant higher than dry land(P=0.000).Parent materials,soil types had extremely significant influence on SOCD(P=0.000),and land-use types had significant influence on SOCD in mesoscale(P=0.017).The comparison result of SOCD showed that alluvium,mudstone, sandshale were extremely significant higher than siltstone(P=0.000);mudstone was extremely significant higher than alluvium(P=0.000),and the later was extremely significant higher than and sandshale(P=0.001).The comparison result of SOCD of different soil types showed that the paddy soil was extremely significant higher than fluvo-aquie soil and yellow soil(P=0.000),and the two laters had no significant difference(P>0.05),but they were extremely significant higher than purple soil (P<0.01).Comparison result of SOCD in different land-use types showed that the paddy field and forest land were significant higher than dry land(P=0.046),extremely higher than forest land(P=0.005),but dry land and forest had no significant difference(P>0.05).Parent materials,soil types had extremely significant influence on SOCD(P=0.000),and land-use types had significant influence on SOCD in mesoscale (P=0.036).The comparison result of SOCD showed that mudstone>alluvium> siltstone>sandshale,and three were extremely significant between each other(P=0.000). The comparison result of SOCD of different soil types showed that the paddy soil was extremely significant higher than fluvo-aquie soil and yellow soil(P=0.000),and the two laters had no significant difference(P>0.05),but they were extremely significant higher than purple soil (P=0.000).Comparison result of SOCD in different land-use types showed that the paddy field,dry land were seperatel significant higher than forest land,paddy field and dry land had no significant difference(P.0.05).更多还原