人工植被对崇明东滩滨海盐土水盐空间异质性的影响  

Effects of artificial vegetation on the spatial heterogeneity of soil moisture and salt in coastal saline land of Chongming Dongtan, Shanghai

作　　者：何斌[1] 蔡永立[1] 冉雯瑞[1] 赵小雷[1] 

机构地区：[1]华东师范大学资源与环境科学学院地理学系,上海200241

出　　处：《应用生态学报》2013年第8期2151-2158,共8页Chinese Journal of Applied Ecology

基　　金：上海市科研计划项目(11dz1211402)资助

摘　　要：运用经典统计学和地统计学相结合的方法,于2012年6月研究了上海市崇明东滩滨海盐土上3种人工植被表层土壤(0～20cm)水盐的空间异质性.结果表明:不同样地的土壤含水量大小顺序为:落羽杉林>狗牙根草丛>夹竹桃灌丛,其变异系数分别为13.9%、13.4%和12.9%;土壤电导率为:夹竹桃灌丛>落羽杉林>狗牙根草丛,其变异系数分别为79.2%、55.4%和15.9%;二者均属中等程度变异.不同样地土壤水盐的理论变异模型各不相同,其中土壤电导率的拟合效果更好,R2在0.97～0.99.当植被从夹竹桃灌丛→狗牙根草丛→落羽杉林,土壤含水量的空间异质性程度由弱变强,其中夹竹桃的变异性是随机的;植被从狗牙根草丛→夹竹桃灌丛→落羽杉林,土壤电导率的空间异质性由中等相关变为强相关.不同植被下土壤电导率空间自相关性多为正相关,土壤水分多呈负相关.狗牙根草丛的土壤水盐均呈条带状分布,落羽杉林地土壤水盐均呈大斑块连续状分布,而夹竹桃灌丛的土壤水分呈小斑块破碎状分布,盐分呈条带状分布.By the methods of classical statistics and geostatistics, this paper studied the spatial heterogeneity of surface soil （0-20 cm layer） moisture and salt contents under three kinds of artificial vegetation in coastal salt land in Chongming Dongtan of Shanghai. The soil moisture content in different plots was in order of Cynodon dactylon Taxodium distichum Nerium indicum, and the coefficient of variation was 13.9%, 13.4% and 12.9%, respectively. The soil electric conductivity was in the order of N. indicum C. dactylon T. distichum, and the coefficient of variation was 79.2%, 55.4% and 15.9%, respectively. Both the soil moisture content and the salt content were in moderate variation. The theoretical models of variogram for the soil moisture and salt contents in different plots varied, among which, the soil electric conductivity fitted better, with R2 between 0.97 and 0.99. When the artificial vegetation varied from N. indicum to T. distichum and then to C. dactylon, the spatial heterogeneity of soil moisture content changed from weak to strong, in which, the variability was random under N. indicum. When the vegetation varied from C. dactylon to T. distichum and to N. indicum, the spatial heterogeneity of soil electric conductivity changed from moderate to strong. Under different vegetations, the soil electric conductivity was mostly in positive correlation, whereas the soil moisture content was in negative correlation. The spatial pattern of soil moisture and salt contents under T. distichum was in striped distribution, that under C. dactylon was in large plaque and continuous distribution, whereas under N. indicum, the spatial pattern of soil moisture content was in small breaking plaque distribution, and that of soil salt content was in striped distribution.

关 键 词：人工植被 土壤水分 土壤电导率 空间异质性 滨海盐土 崇明东滩 

分 类 号：S156.4[农业科学—土壤学]