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1.
Tao  Shu 《Water, air, and soil pollution》1998,102(3-4):415-425
The abundances of copper, lead, zinc, nickel, chromium, cobalt, mercury, vanadium, and manganese in eighty three surface soil samples collected from Shenzhen area were determined. The correlation among element contents and the factors affecting the contents were studied using principle component analysis. The factor scores of the first two components were analyzed as regionalized variables using variogram analysis and Kriging. The interpolated factor scores were then mapped to show the common features in spatial distribution of a set of elements with similar geochemical behavior. It was demonstrated that the spatial distribution patterns of parent material in the area are the primary factor governing the spatial variation of the elements.  相似文献   

2.
【目的】 本研究旨在通过分析污染物空间结构特征解析典型污灌区土壤重金属污染成因。 【方法】 本文以北京市东南郊污灌区为例,在整个区域均匀布点,按1 km × 1 km密度采样,共采集土壤样品376个。每个样点为10 m × 10 m正方形,在四个顶点和中心点取0—20 cm表层土壤,均匀混合后用四分法从中选取1 kg土壤,作为代表该点的混合样品。Cu和Pb重金属含量采用原子吸收火焰法进行测定,利用Variowin2.0和ArcGIS10.2软件分析重金属空间结构及分布特征,解析其污染成因。 【结果】 研究区域土壤Cu和Pb空间结构均为套合结构,其块金值与基台值的比值在25%~75%之间。Cu和Pb的空间分布与河流走向密切相关,在西北–东南方向空间相关性较强,其高值区主要分布在研究区域中北部的凉水河流域、西部的永定河流域以及通州的东北部。 【结论】 污水灌溉和成土母质是研究区域土壤重金属的主要来源。由污水灌溉等小尺度因素主导的土壤Cu和Pb元素空间自相关距离分别为11.35 km和9.49 km;由成土母质等大尺度因素主导的空间自相关距离分别为26.65 km和31.70 km。通过分析不同尺度因素对区域土壤重金属含量空间分布的影响,可揭示土壤重金属污染成因,这种思路可为其他区域开展土壤重金属污染成因研究提供借鉴。   相似文献   

3.
四川省仁寿县土壤有机碳空间分布特征及其主控因素   总被引:6,自引:0,他引:6  
准确地获取区域尺度内土壤有机碳含量信息对土壤碳调控及全球环境变化具有重要意义。本研究基于野外实地采集的555个表层(0~20 cm)土样,探讨四川省仁寿县土壤有机碳空间分布特征及其主控因素。运用方差分析和回归分析对比了成土母质、土壤类型和土地利用方式对仁寿县土壤有机碳空间分布的影响。结果表明:研究区表层土壤有机碳含量为3.36~37.10 g·kg-1,平均13.46 g·kg-1,变异系数为48.87%,属中等强度的空间变异性。块金效应C0/(C0+C)为66.7%,空间分布受结构性因素和随机性因素的共同影响,总体呈现北高南低的趋势。土地利用方式和土壤类型对土壤有机碳的影响极显著(P0.01),而成土母质的影响不明显(P=0.256)。土类能够独立解释23.7%的土壤有机碳空间变异;亚类和土类的解释能力接近,分别为27.0%和27.1%,土壤亚类可作为探讨该区域土壤有机碳空间变化的最小土壤分级单元。土地利用方式能独立解释53.0%的土壤有机碳空间变异,远大于土壤类型,是研究区土壤有机碳空间分布的主控因素。  相似文献   

4.
The magnitude of variation in soil properties can change from place to place, and this lack of stationarity can preclude conventional geostatistical and spectral analysis. In contrast, wavelets and their scaling functions, which take non‐zero values only over short intervals and are therefore local, enable us to handle such variation. Wavelets can be used to analyse scale‐dependence and spatial changes in the correlation of two variables where the linear model of coregionalization is inadmissible. We have adapted wavelet methods to analyse soil properties with non‐stationary variation and covariation in fairly small sets of data, such as we can expect in soil survey, and we have applied them to measurements of pH and the contents of clay and calcium carbonate on a 3‐km transect in Central England. Places on the transect where significant changes in the variance of the soil properties occur were identified. The scale‐dependence of the correlations of soil properties was investigated by calculating wavelet correlations for each spatial scale. We identified where the covariance of the properties appeared to change and then computed the wavelet correlations on each side of the change point and compared them. The correlation of topsoil and subsoil clay content was found to be uniform along the transect at one important scale, although there were significant changes in the variance. In contrast, carbonate content and pH of the topsoil were correlated only in parts of the transect.  相似文献   

5.
Coregionalization of trace metals in the soil in the Swiss Jura   总被引:7,自引:0,他引:7  
The provenance of trace metals in soil, whether from the parent material or from pollution, is rarely known with certainty, and the metals' history must usually be pieced together from fragmentary statistical information. This is particularly true in the Swiss Jura where the concentrations of several heavy metals around La Chaux de Fonds exceed the statutory recommended thresholds for safety. The topsoil of the 14.5-km2 region was sampled on a square grid at 250-m intervals with additional nesting with distances of 100 m, 40 m, 16 m and 6 m. The concentrations of seven potentially toxic metals, namely Cd, Co, Cr, Cu, Ni, Pb and Zn, were measured. Their coregionalization could be represented by a linear model consisting of a nugget component plus two spherical structures with ranges of 0.2 km and 1.3 km. The short-range component dominated the variograms of Cd, Cr, Cu and Pb; the long-range component dominated those of Co and Ni; the variogram of Zn combined the two in approximately equal proportions. The coregionalization matrices contain moderate correlation among the nugget and the short-range components, notably between Cu and Pb, between Cd and Zn, and between Cr, Ni and Zn. The strongest correlations are at the long range between Co, Cr and Ni, and to a somewhat smaller degree between Zn and Co. Analysis of variance showed Co and Ni to be related to geology, and to the Argovian formation in particular. The indicator variogram of this formation has also a short-range component. The analysis also showed Cr and Cu to be related to land use (in different ways). Copper and Pb are strongly correlated to one another and distinct from the five other metals. The long-range structure is almost certainly a geological effect, whereas the one of short range probably results from both the geology and human activities.  相似文献   

6.
Most studies of relations between soil properties fail to take account of their regionalized nature because of the lack of appropriate methods. This paper describes a geostatistical technique, factorial kriging analysis, that bridges the gap between classical multivariate analysis and a univariate geostatistical approach. The basic feature of the method is the fitting of a linear model of coregionalization, i.e. all experimental simple and cross-variograms are modelled with a linear combination of basic variogram functions. A particular variance-covariance matrix, the coregionalization matrix, can then be associated with each spatial scale defined by the range of the basic variogram function. Each coregionalization matrix describes relationships between variables at a given spatial scale. A principal component analysis of these matrices produces a set of components, the regionalized factors, that reflect the main features of the multivariate information for each spatial scale and whose scores are estimated by cokriging. The technique is described and illustrated with three case studies based on a simulated data set and soil survey data. The results are compared with those of the principal component analysis of the variance-covariance matrix and the variogram matrices.  相似文献   

7.
Eighty-three surface soil samples were collected from the Shenzhen area for determination of copper, lead, and mercury contents. The nature of spatial dependence of the measured results was quantified using variogram analysis. All variograms show well-defined structure with zero nugget and distinct sills and ranges and can be fitted by a spherical model. The range scale and the geometric anisotropy of the variograms suggest that the spatial structures of copper and lead relate closely to the distribution of parent material in the area. The variogram of mercury appears to be isotropic with a relatively small range, indicating significant influence of geographical distribution of paddy soil fields that have been severely polluted by agricultural practice.  相似文献   

8.
本文以河南豫北、豫中和豫南3个典型样区为研究对象,运用地统计学方法,从多样性、相关性角度定量分析了地形、土壤的多样性特征及其与耕地变化(2001年、2007年和2017年)面积的空间分布多样性特征的关系,以期为耕地资源动态变化的驱动力分析及合理利用提供新的研究角度。研究表明:1)豫北和豫中样区的地形构成组分多样性呈现出均匀性,豫南样区表现为相对单一性;各研究区的地形空间分布多样性为平原丘陵山地。2)豫南的土壤构成组分最为均匀且丰富,豫中的土壤构成组分相对单一;各研究区的典型土壤各异但总体上分布皆较均匀,各样区的土壤空间分布多样性的显著差异与地形条件密切相关。3)研究尺度影响地形、土壤空间分布多样性特征的表达, 3 km×3 km网格是相对适宜的研究尺度。4)地形和土壤的空间分布多样性指数与耕地变化面积空间分布都具有明显的相关性,其中地形中平原相关性较大,达0.95左右;各样区典型土壤如豫南的水稻土,豫中、豫北的褐土以及豫北的潮土的相关性更为明显,达0.9以上。综合来看,典型样区的地形、土壤因子的构成组分多样性及空间分布格局有显著差别;在不同网格尺度下,耕地的变化面积与地形、土壤因子的空间分布多样性指数密切相关。  相似文献   

9.
江叶枫  饶磊  郭熙  叶英聪  孙凯  李婕  王澜珂  李伟峰 《土壤》2018,50(4):778-786
准确地获取省域尺度下土壤有机碳空间变异的主控因素对土壤碳调控以及全球环境保护具有重要意义。本文基于江西省2012年测土配方施肥项目采集的16 582个耕地表层(0~20 cm)土壤样点数据,探讨江西省耕地表层土壤有机碳空间变异的主控因素。运用普通克里格法、单因素方差分析与回归分析方法对比地形因子、耕地利用方式、成土母质、土壤类型、灌溉能力和秸秆还田方式对江西省土壤有机碳空间分布的影响。结果表明:(1)江西省土壤有机碳含量在5.22~40.31 g/kg之间,平均值为17.90 g/kg,变异系数为31.01%,呈中等程度的变异性。(2)经半方差分析,土壤有机碳的变程为30.6 km,空间自相关范围较小;块金效应值为12.49%,表明土壤有机碳空间变异受结构性因素影响大于随机性因素。(3)在空间分布上,高值区主要分布在萍乡市、新余市、南昌市、抚州市与景德镇市。(4)回归分析与单因素方差分析结果表明,地形因子、灌溉能力、成土母质、耕地利用方式、土壤类型和秸秆还田方式对土壤有机碳空间变异影响均显著(P0.05),但影响程度不一。秸秆还田方式对土壤有机碳空间变异的独立解释能力最高,为38.9%,是江西耕地表层土壤有机碳空间变异的主控因素。  相似文献   

10.
单种复合类型单元土壤全量元素空间变异的幅度效应   总被引:1,自引:1,他引:0  
土壤属性变异性的幅度效应研究对土壤数字制图、土壤调查及农业生产均具有重要意义。针对江西东乡县研究区域水田—中潴灰鳝泥田(土种)一种土地利用与土壤的复合类型单元,设定了8个土壤采样幅度研究区,并利用多层次嵌套布点方法在每个采样幅度区分别布设60个采样点,共采集337个样点的土壤表层(0~20cm)样品;运用多种函数拟合分析手段,揭示单种复合类型单元(水田—中潴灰鳝泥田)土壤全氮、全磷、全钾含量的空间变异性随采样幅度的变化特征。结果表明,土壤全量元素的空间变异性均具有明显的幅度效应特征,全氮、全磷、全钾含量的变异系数均随采样幅度的拓展而逐渐增加,而增加趋势则逐渐变缓。不同土壤全量元素空间变异性体现出不同的幅度效应特征,土壤全氮、全磷变异系数(%)的幅度效应刻画函数为CV=b×Da(R20.87,p0.001),土壤全钾为CV=e(a/D+b)(R20.93,p0.001),D为幅度表征指标(km);不同土壤全量元素变异系数随采样幅度快速与缓慢变化的幅度分界点位置存在明显差异,表明基于复合类型单元的土壤多属性调查采样布点与分析策略需要统筹考虑。研究结果对于红壤丘陵区县域土壤调查样点合理布设具有重要的启示和参考价值。  相似文献   

11.
在面积约10.9km2的重金属污染场地以网格法采集了174个表层土壤样品,测定了7种重金属含量。采用地统计学软件GS 和地理信息系统相结合的方法,研究了这些重金属含量的空间变异性。通过Kriging内插法对未测点重金属含量进行最优估计,并对这些重金属的来源进行了初步识别。结果发现,在研究区内7种重金属具有相似的空间分布特征,污染场地特殊的污染源分布状况、污染程度和地理条件导致点状污染源增大了重金属的空间结构性,呈现出与非典型污染区不同的特征。冶炼厂高炉粉尘排放对重金属的贡献明显高于母质等内在因素,是研究区重金属的主要来源。  相似文献   

12.
This paper presents two indicator algorithms that integrate soil map information into modelling the spatial variation of continuous soil properties: these are simple indicator kriging with varying means and the Markov–Bayes algorithm. Both methods are used to evaluate probabilities for copper and cobalt deficiencies in the Borders Region of Scotland. Results are compared with maps obtained by the polygonal method (Thiessen polygons) and an indicator kriging algorithm that does not use soil map information. Accounting for soil map information is shown to improve delineation of the deficient areas, especially where the sampling is sparse. Test locations are classified as deficient or not so as to minimize an expected cost of mis-classification that is derived from local probability distributions of copper or cobalt and functions measuring the cost of overestimating or underestimating metal concentrations. The comparison of classification results with actual copper and cobalt concentrations at test locations shows that the two proposed algorithms can decrease substantially the economic loss attached to misclassification.  相似文献   

13.
铁岭凡河稻田土壤有效态中、微量元素空间变异特征研究   总被引:8,自引:1,他引:8  
试验应用地理信息系统和地统计学方法对铁岭凡河稻田土壤有效中量、微量元素的空间变异特征进行了研究。发现土壤有效钙、有效镁、有效硫、有效铁、有效铜和有效锰受地形、母质、灌溉和土壤物理、化学过程的长期影响,具有显著的方向性空间变异和自相关特征,其最大相关距可达500m左右。这一研究成果对该地区稻田土壤养分管理具有重要意义。  相似文献   

14.
区域土壤有机碳空间分布特征与尺度效应   总被引:2,自引:1,他引:1  
结合当前土壤属性空间分布特征及其尺度效应研究进展和不足,综合采用变异函数理论、空间自相关理论、多重分形理论等方法从土壤有机碳(soil organic carbon,SOC)空间变异性、相关性和结构性等不同层面深入揭示不同尺度下SOC空间分布特征及其尺度效应。研究结果表明:除了15 km尺度外,基于变异函数分析的其他尺度块基比均小于50%,结构性因素占主导,结构性因素主要包括土壤亚类、土地质地、土地类型等,随机部分带来的空间变异性随着尺度的增加呈现减少趋势;不同尺度下的莫兰指数随着分离距离的增加由完全正值逐渐变小,过渡到正负交替出现的格局,最后完全变为负值,标准化统计量均大于1.96,每个尺度均具有良好的空间结构;不论是瑞利谱图,还是多重分形谱,随着尺度的增加,图谱越来越接近,研究区不同尺度下的SOC在空间上的分布是典型的分维数体;无论何种尺度,基于多重分形克里格法的实测值与预测值特异值空间吻合程度较高,特异值覆盖比率均在85%以上。联合了变异函数、空间自相关、多重分形和多重分形克里格等方法能够从空间变异性、空间相关性、空间结构性等更加深入全面地揭示研究区SOC空间分布特征。研究成果可为相对平坦农业区域土壤有机碳空间分布特征研究提供方法支撑。  相似文献   

15.
周洋  赵小敏  郭熙  韩逸 《核农学报》2021,35(6):1420-1432
为了对江西省赣州市寻乌县土壤硼(B)、硒(Se)、锰(Mn)、铜(Cu)4种微量元素的空间分布特征进行探究,同时分析影响其分布的因子,基于寻乌县2018年采集的572个表层土壤(0 ~ 20 cm)样点数据,采用描述性统计分析、相关性分析、地统计分析、地理探测器等方法进行分析。结果表明,根据《土地质量地球化学评价规范》划分标准,寻乌县4种微量元素中,土壤全量Se含量处于适中或较高的水平,不存在缺乏和过剩的情况,而土壤全量B、Mn和Cu含量处于较缺乏或缺乏的水平;由半方差函数分析的结果来看,B、Se、Mn、Cu的块金效应依次为11.82%、35.27%、49.75%和17.46%,表明4种微量元素中,B和Cu表现出较强的空间变异程度,而Se和Mn则为中等程度的空间变异。地理探测器的结果表明,重金属元素砷(As)含量、高程、土壤亚类和土属、成土母质对4种微量元素均有显著影响(P<0.05),其中As含量和土属对4种微量元素的解释能力较强,是影响寻乌县4种微量元素的主要因子;土壤重金属元素As含量、土地利用类型、植被覆盖度、植被类型以及土属、成土母质等成土因子均与坡度、坡向等地形因子有着非线性增强的交互作用。本研究结果为调节寻乌县土壤微量元素含量提供了理论支撑。  相似文献   

16.
Observations of ancillary soil properties spatially correlated to a soil property of interest may be used to increase the precision and reduce the sampling costs of a geostatistical survey. The relationship between such coregionalized properties must be expressed as a linear model of coregionalization but the conventional estimator of the linear model of coregionalization is biased unless the mean value of each property is constant across the study region. However, the mean value of a soil property may vary according to a spatial trend or a deterministic relationship with other factors which vary within the study region. We therefore propose that a linear mixed model should be fitted to coregionalized soil properties by residual maximum likelihood. This approach simultaneously fits spatial trends or deterministic relationships and random effects to the observations with minimum bias. We implement a residual maximum likelihood estimator for coregionalized properties and suggest a criterion to decide what order of spatial trend and which deterministic relationships should be included in the model. The effectiveness of the estimator is proved upon simulated data and upon observations of zinc and cadmium concentrations from the Swiss Jura.  相似文献   

17.
The levels of the accumulation of copper, lead, nickel, and cadmium in the parent material-soil-plants-soil organic matter system are given for gray forest soils in the Buryat Republic. The concentrations of copper, lead, and nickel in the parent materials do not exceed the corresponding clarkes, and cadmium is present in trace amounts. The concentrations of copper and nickel in the humus horizon are lower than those in the parent material; an opposite situation is observed for lead. The concentrations of copper, lead, and nickel in the soil organic matter and in the herbaceous plants correspond to their contents in the soil and do not exceed the background (clarke) values. Cadmium was not detected in the aboveground part of the plants, though it was found in the root mass and in the organic soil horizon. In the humus of gray forest soils, these heavy metals are mainly present in the acid filtrate remaining after the precipitation of humic acids.  相似文献   

18.
Quantitative predictions of ammonia volatilization from soil are useful to environmental managers and policy makers and empirical models have been used with some success. Spatial analysis of the soil properties and their relationship to the ammonia volatilization process is important as predictions will be required at disparate scales from the field to the catchment and beyond. These relationships are known to change across scales and this may affect the performance of an empirical model. This study is concerned with the variation of ammonia volatilization and some controlling soil properties: bulk density, volumetric water content, pH, CEC, soil pH buffer power, and urease activity, over distances of 2, 50, 500, and >2000 m. We sampled a 16 km × 16 km region in eastern England and analyzed the results by a nested analysis of (co)variance, from which variance components and correlations for each scale were obtained. The overall correlations between ammonia volatilization and the soil properties were generally weak: –0.09 for bulk density, 0.04 for volumetric water content, –0.22 for CEC, –0.08 for urease activity, –0.22 for pH and 0.18 for the soil pH buffer power. Variation in ammonia volatilization was scale‐dependent, with substantial variance components at the 2‐ and 500‐m scales. The results from the analysis of covariance show that the relationships between ammonia volatilization and soil properties are complex. At the >2000 m scale, ammonia volatilization was strongly correlated with pH (–0.82) and CEC (–0.55), which is probably the result of differences in parent material. We also observed weaker correlations at the 500‐m scale with bulk density (–0.61), volumetric water content (0.48), urease activity (–0.42), pH (–0.55) and soil pH buffer power (0.38). Nested analysis showed that overall correlations may mask relationships at scales of interest and the effect of soil variables on these soil processes is scale‐dependent.  相似文献   

19.
孙奥  段碧辉  王芳  项剑桥  夏伟  王天一 《土壤》2022,54(3):637-645
本研究以鄂西咸丰县土壤为研究对象,统计了区内表层土壤中30种元素指标的地球化学背景值,再结合因子分析方法,探讨了地球化学背景值的成因机制,分析了土壤元素空间分布及其影响因素。结果表明,咸丰地区土壤B、Cd、Cr、F、Hg、Se元素的含量明显高于全国和湖北省背景值,I、Mo、Sr、Ca O、Na2O等元素较全国贫乏。因子分析结果表明成土母质、工矿活动、腐殖质过程、风化作用、地形因素以及人类的生产活动共同影响着研究区内表层土壤的背景值特征,其中成土母质决定了土壤中化学元素的分布特征,但是工矿活动、地形特征和人类活动等过程重塑了区域元素分布特征。  相似文献   

20.
Knowledge about spatial soil variation in terms of measured pedodiversity, as well as the spatial distribution of soils in terms of spatial subset representativity, offers the possibility to estimate the quality and variance within a soil map. Additionally, it can help to identify representative sample locations. Demonstrated at the German soil map at a scale of 1:1,000,000, this study describes a methodology to analyze the distribution of taxonomical pedodiversity using the Simpson index and a new approach to derive representative spatial subsets based on a modified χ2‐test (χm2), which can be used as monitoring areas. To analyze the spatial composition of the soil map and to detect differences in the underlying mapping schemes of the German soil map 1:1,000,000, three different spatial data structures were studied: (1) the entire soil map, (2) the soil map segmented into geomorphological regions, and (3) the soil map segmented into the Federal States of Germany. Representative patches of varying sizes were statistically derived for all spatial subsets as well as the entire soil map ranging from 20 km × 20 km up to 70 km × 70 km. The results show that the measured pedodiversity is linked to both the geomorphology as well as the political borders of the Federal States. On the one hand, this reveals the uncertainty of measuring pedodiversity on the basis of soil‐class maps as the spatial representation of pedodiversity is influenced by the different mapping traditions and methods applied in the 16 Federal States of Germany. On the other hand, it allows the analysis of the aggregation schemes of different landscapes. The presented approach helps to understand large soilscapes and to compare different soil maps of different states and countries as well as to enhance the soil map with additional information. Furthermore, the representative patches can be used to select soil‐monitoring areas.  相似文献   

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