典型岩溶流域土壤有机质空间变异——以云南小江流域为例

以云南小江流域为例,利用地统计学与GIS相结合研究岩溶区土壤有机质的空间变异。统计分析结果表明,研究区内土壤有机质含量的总体水平较高,平均为29．0g／kg,变异系数为60．5％,属强变异;半方差函数分析结果表明,流域土壤有机质含量的空间变异具有各向异向性,长、短轴变程分别为39．8km和22．0km,同时由空间自相关部分引起的空间变异性的程度较大,C0／（C0＋C1）值为53．4％,流域土壤有机质含量具有中等的空间相关性;Kriging插值分析结果表明流域土壤有机质含量由东部向西、西南部逐渐降低,其空间分布与流域地质、地貌及土地利用表现出明显的一致性。     

典型岩溶流域景观格局动态变化——以云南小江流域为例

根据云南小江流域 1982年的航片和 2 0 0 3年的 TM影像及实地调查资料 ,获得流域两期景观类型图 ,利用 GIS、RS和景观生态学的理论和方法 ,分析了典型岩溶流域景观格局的动态变化及驱动机制。结果表明 :流域 6 10 .12 km2的景观类型发生变化 ,占流域景观总面积的 5 9% ;景观类型变化主要由未利用地向耕地和林地以及林地向耕地的转化 ;流域景观变化速度十分迅速 ,综合变化动态度达 2 .95 % ,园地和耕地景观变化动态度达 34.0 9%、10 .5 5 % ;流域景观的斑块数增加 86 .3% ,平均斑块面积减少 4 6 .1% ,流域景观的基本构型由以大斑块为主体 ,中、小型斑块镶嵌其中转变为以中等斑块为主体 ,大、小型斑块镶嵌其中的构型 ;流域景观多样性指数增长 4 .14 % ,破碎度指数增长 84 .6 % ;未利用地、林地的分离度指数分别增加 114 .5 8%和6 9.6 4 % ,而耕地的分离度指数减少 4 5 .86 % ;流域耕地、建设地重心向东北方向迁移 ,而未利用地、林地、重心向南东、南西方向迁移 ;人文因素是流域景观格局变化的直接驱动力 ,人口增长、经济发展是流域耕地景观变化进而导致系列景观变化最根本的原因 ,而比较经济利益和理智的生态环境保护政策是流域林地景观变化的主要原因     

季风边缘区极端降水变化及其影响因素——以石羊河流域为例

全球变暖导致大气湿度和降水强度总体增加,也加剧了极端降水事件的发生.科学认识区域极端降水变化规律及其影响对水资源的管理与合理利用、生态保护与治理、农业的可持续发展等具有重要的现实意义.本文基于1960-2018年石羊河流域4个气象站逐日降水量数据,采用一元线性回归分析以及相关分析法,对石羊河流域极端降水变化特征及其影响...     

Spatial variability of soil fertility factors in the Xiangcheng tobacco planting region, China

It is essential to understand the spatial variability of soil properties in tobacco planting regions, so that the right decision can be made as to how many fertilizer rates are likely to be appropriated for the high-quality tobacco production. A total of 159 soil samples were taken from the surface soil (0-20cm) in the Xiangcheng tobacco planting fields, Henan Province, in April 2002 to examine the concentration of soil organic matter, pH, available N, available P, and available K. The spatial variability was evaluated using geostatistics and geographic information system (GIS) analyses. The results show that among those five soil fertility factors, the variation coefficient of soil pH was the smallest, while that of available P was the greatest, which resulted from different cultivation methods and uneven fertilization. Analysis of the isotropic variogram indicated that the soil pH, organic matter, and available P semivariogram were well described with spherical models, with the distance of spatial dependence being 21020, 19150, and 8460m, respectively, whereas the available N and available K semivariogram were well described with an exponential model, with the distance of spatial dependence being ranged from 7484 to 25320 m. Soil pH value was strongly spatially dependent with C0/sill being 0.1935, while the other four soil fertility factors were moderately spatially dependent with C0/sill ranging between 0.3528 to 0.5260. Through the Kriging analysis, the spatial distribution maps of soil properties were drawn using the arcview software. This study provides a scientific basis for field management, which targets soil quality improvement in the Xiangcheng tobacco planting region.     

Spatial variability of soil fertility factors in the Xiangcheng tobacco planting region, China

It is essential to understand the spatial variability of soil properties in tobacco planting regions, so that the right decision can be made as to how many fertilizer rates are likely to be appropriated for the highquality tobacco production. A total of 159 soil samples were taken from the surface soil (0-20 cm) in the Xiangcheng tobacco planting fields, Henan Province, in April 2002 to examine the concentration of soil organic matter, pH, available N, available P, and available K. The spatial variability was evaluated using geostatistics and geographic information system (GIS) analyses. The results show that among those five soil fertility factors, the variation coefficient of soil pH was the smallest, while that of available P was the greatest, which resulted from different cultivation methods and uneven fertilization. Analysis of the isotropic variogram indicated that the soil pH, organic matter, and available P semivariogram were well described with spherical models, with the distance of spatial dependence being 21020, 19150, and 8460 m, respectively, whereas the available N and available K semivariogram were well described with an exponential model, with the distance of spatial dependence being ranged from 7484 to 25320 m. Soil pH value was strongly spatially dependent with C0/sill being 0.1935, while the other four soil fertility factors were moderately spatially dependent with C0/sill ranging between 0.3528 to 0.5260. Through the Kriging analysis, the spatial distribution maps of soil properties were drawn using the arcview software. This study provides a scientific basis for field management, which targets soil quality improvement in the Xiangcheng tobacco planting region.     

黄花甸子流域土壤全氮含量空间分布及其影响因素

以内蒙古赤峰市敖汉旗黄花甸子流域为研究对象,运用地统计学方法分析流域内土壤全氮含量的空间分布特征及地形因子和土地利用方式对其的影响.结果表明:流域内各土层土壤全氮含量均呈岛状分布,其高值区均集中分布在流域西北部,呈现出明显肥岛状;低值区主要在流域南部连片分布.全氮主要富集在表层土壤中,且随着土壤深度的增加而降低.土壤全氮含量随着海拔的增加均呈现出先增高后降低的趋势;随坡度的增加而显著降低;不同坡向上表现为阴坡＞半阴坡＞半阳坡＞阳坡.不同土地利用方式下土壤全氮平均含量由高到低表现为农地＞林地＞草地.     

浙江清凉峰自然保护区土壤肥力指标空间变异及其影响因素

为了探究清凉峰自然保护区内华南野生梅花鹿主要栖息地千顷塘的土壤肥力指标的空间变异规律及其相关影响因子,采用经典统计学和地统计学方法对千顷塘土壤pH、有机质、全磷、全氮、全钾含量进行了系统分析,并探讨了其主要影响因子。结果显示：千顷塘保护区内土壤整体呈酸性,区域内有机质、全磷、全氮、全钾含量均值分别为72.44、0.45、1.91、23.16 g/kg,所有指标均呈现中等程度变异。半方差分析结果表明,指数模型为pH、全磷、全氮、全钾的最佳拟合模型,球状模型为有机质最佳拟合模型,pH、全磷、全钾空间自相关强烈,显示其空间变异主要受结构性因素影响,有机质和全氮空间自相关程度中等,说明随机因素存在一定影响。全局Moran′s I指数检验结果显示,有机质、全磷和全氮存在显著空间自相关,在空间上呈现聚集分布。所有肥力指标的空间分布较为连贯,条带状分布特征显著,总体呈现由边缘向中间降低趋势;相关性分析显示,土壤有机质、全磷、全氮、全钾与海拔、容重和植被类型呈显著相关性;回归分析表明,在所有环境因子中,容重对各类元素的方差解释最大,是影响千顷塘土壤肥力因子空间异质性的主控因素。研究可为南方丘陵地区人为...     

泸沽湖流域土地利用方式对土壤肥力的影响

为探讨泸沽湖流域不同土地利用方式对土壤肥力的影响,采用野外调查、取样和室内分析相结合的方法,对泸沽湖流域内3种主要土地利用方式(农田、草地、林地)的土壤理化性状进行对比分析。结果表明:(1)土地利用类型对土壤肥力影响明显,农田含水率、全氮、速效氮、速效磷和速效钾含量相对较高;(2)林地有机质含量相对较高,草地全磷全钾含量相对较高;(3)土壤养分含量与土壤颗粒组成之间有一定的相关性,其中土壤全磷与砂粒呈显著正相关,土壤速效氮含量与粉粒呈显著负相关。     

Temporal-spatial variation and the influence factors of precipitation in Sichuan Province, China

Precipitation is a key factor in the water cycle.At the same time,precipitation is the focus of study in meteorology and climatology,ecological environmental assessment,non-point source pollution and so on.Understanding the temporal-spatial variation and the corresponding factors of precipitation has become the object of hydrology and environmentology.Based on the annual precipitation data,we analyzed the spatial distribution of precipitation in Sichuan Province in China as well as the temporal-spatial variation and the corresponding influence factors involved.The results show that the amount of precipitation was abundant,but the spatial distribution was not consistent with it and the amount of precipitation gradually declined from the south-east to the north-west in Sichuan Province,China.Moreover,the spatial distribution was different throughout the years.The result of correlation analysis indicated that elevation,temperature and air pressure were three key factors affecting the amount and distribution of precipitation,and the correlation coefficients were -0.56,0.38 and 0.45 respectively.Notably,the relationship between the slope of topography and precipitation were significantly negative and the average correlation coefficient was -0.28.     

Temporal-spatial variation and the influence factors of precipitation in Sichuan Province, China

Precipitation is a key factor in the water cycle. At the same time, precipitation is the focus of study in meteorology and climatology, ecological environmental assessment, non-point source pollution and so on. Understanding the temporal-spatial variation and the corresponding factors of precipitation has become the object of hydrology and environmentology. Based on the annual precipitation data, we analyzed the spatial distribution of precipitation in Sichuan Province in China as well as the temporal-spatial variation and the corresponding influence factors involved. The results show that the amount of precipitation was abundant, but the spatial distribution was not consistent with it and the amount of precipitation gradually declined from the south-east to the north-west in Sichuan Province, China. Moreover, the spatial distribution was different throughout the years. The result of correlation analysis indicated that elevation, temperature and air pressure were three key factors affecting the amount and distribution of precipitation, and the correlation coefficients were −0.56, 0.38 and 0.45 respectively. Notably, the relationship between the slope of topography and precipitation were significantly negative and the average correlation coefficient was −0.28.     

基于GIS长春市郊农地土壤肥力综合评价

以长春市郊区农地为例,应用ArcInfo进行空间数据采集、处理与分析,以土地利用类型作为评价单元,采用层次分析法确定评价因素的权重,引入模糊数学方法,建立各评价因素对肥力的隶属函数,计算各个肥力评价因素的评分,最后用指数和法求出各评价单元的综合评价值,根据综合评价值的大小划分土壤肥力等级,并分级统计其面积.应用ArcView GIS绘制了评价结果图.