Statistical Methods in Soil and Land Resource Survey.

Webster, R.; Oliver, M. A.

doi:10.2307/2532283

Cited by 247 publications

(325 citation statements)

References 0 publications

Supporting

Mentioning

280

Contrasting

Unclassified

Order By: Relevance

“…Semivariograms showed that lnCd and pH were all fitted for spherical model, whereas SOM was best fitted for an exponential model. Range value is a measure of extension where autocorrelation exists (Webster and Oliver, 1990;Li et al, 2007). The effective range of Cd was very close to that of pH, suggesting that they had similar spatial correlation structures and their distribution was affected by similar influence factors.…”

Section: Spatial Characteristics Of CD Ph and Som In Topsoilsmentioning

confidence: 85%

“…The semivariogram, the main component of kriging, is an effective tool for evaluating spatial variability and structure (Boyer et al, 1991;Cahn et al, 1994;Guo et al, 2001;Iqbal et al, 2005). The variogram provides a clear description of the spatial structure of variables and some insight into possible processes affecting variable distribution (Webster and Oliver, 1990;Paz González et al, 2001).…”

Section: Geostatistical Analysismentioning

confidence: 99%

See 1 more Smart Citation

Spatial characteristics of cadmium in topsoils in a typical e-waste recycling area in southeast China and its potential threat to shallow groundwater

Luo

Deng

et al. 2014

Science of The Total Environment

View full text Add to dashboard Cite

• We characterize the Cd total in topsoils, pH and SOM in a typical e-waste recycling area.• The relationships between Cd total in topsoils, pH, and SOM were studied.• Impact of topsoil Cd accumulation and acidification on shallow groundwater quality was evaluated. Informal electrical and electronic waste (e-waste) recycling often creates secondary sources of cadmium (Cd) pollution. To characterize the total Cd concentration (Cd total ) in topsoil and evaluate the threat of Cd in topsoils to shallow groundwater, 187 topsoil samples and 12 shallow groundwater samples were collected in a typical e-waste recycling area in southeast China. Soil organic matter content, soil pH and Cd total in topsoil, pH and dissolved Cd concentration in shallow groundwater were measured. Cd total in the topsoils showed an inverse distribution trend with soil pH in that high Cd concentrations (and low pH values) were found in the surrounding area of the metal recycling industrial park where there were many family-operated e-waste recycling facilities before the industrial park was established and with low concentrations (and high pH values) in other areas, and they had similar spatial correlation structures. Cd accumulation and acidification were synchronous in topsoils, and soil pH was significantly correlated with Cd total in topsoils with low to moderate negative correlation coefficient (r = −0.24), indicating that both of them maybe correlated with informal recycling. The shallow groundwater in the surrounding area of the metal recycling industrial park was seriously contaminated by Cd, and topsoil Cd accumulation and acidification in the surrounding area of e-waste recycling sites significantly increase the risk of shallow groundwater contaminated by Cd. Action is urgently required to control Cd accumulation and acidification by improving the recycling operations of e-wastes in order to reduce the risk of Cd leaching from topsoils and shallow groundwater contamination. a b s t r a c t a r t i c l e i n f o

show abstract

Section: Spatial Characteristics Of CD Ph and Som In Topsoilsmentioning

confidence: 85%

Section: Geostatistical Analysismentioning

confidence: 99%

Spatial characteristics of cadmium in topsoils in a typical e-waste recycling area in southeast China and its potential threat to shallow groundwater

Luo

Deng

et al. 2014

Science of The Total Environment

View full text Add to dashboard Cite

show abstract

“…Ela consiste da variografia, krigagem, simulações e de estratégias que otimizem os planos de amostragem dos atributos (Webster & Oliver, 1990).…”

Section: Introductionunclassified

Geoestatística no estudo de modelagem temporal da precipitação

Almeida¹,

Ribeiro²,

Paiva³

et al. 2011

Rev. bras. eng. agríc. ambient.

View full text Add to dashboard Cite

RESUMOA análise geoestatística é uma poderosa ferramenta utilizada em estudos de dependência espacial. No que tange à dependência temporal, poucas são as análises realizadas com essa metodologia. Neste trabalho foi utilizada a técnica de geoestatística para ajustar um modelo de série temporal de precipitação, cujo poder é avaliado em predizer valores futuros. O estudo foi realizado na Bacia do Rio Itapemirim em uma série de precipitação mensal de 1940 a 2006. O modelo geoestatístico foi comparado com um modelo de séries temporais de Box e Jenkins. O modelo geoestatístico ajustado foi aquele com 96 vizinhos utilizados na previsão e erro relativo absoluto médio de 80,46. A metodologia de geoestatistica apresentou melhores resultados na estimação da precipitação mensal, em relação ao modelo SARIMA (2,1,1)(0,1,1) 12 . Palavras-chave: Bacia do Rio Itapemirim, Box & Jenkins, series temporaisGeostatistics in the temporal modeling study of precipitation ABSTRACT Geostatistics analysis is a powerful tool which has been used in studies of spatial dependence. With respect to the temporal dependence, few analysis are performed with this kind of methodology. In this study, the geostatistics technique was used to adjust a model to a series of temporal values of precipitation and its performance to predict data was also evaluated. The study was carried out at the Rio Itapemirim Basin in a series of monthly precipitation from 1940 to 2006. The adjusted model was compared to the Box and Jenkins model. The best geostatistics model adjusted was the one which used with 96 neighbors in the prediction and mean relative absolute error of 80.46. Geostatistics methodology showed better results for estimating the monthly precipitation in relation to the SARIMA model (2,1,1)(0,1,1) 12 .

show abstract

“…In addition, they send a warning about the variability of physical attributes within the same soil class and with the same management history. Therefore, the use hillslope curvatures can be useful in outlining similar management areas in the field and in determining the sampling scheme, acknowledging the need to determine the number of samples and spacing between them, which is a constant concern in soil science (Webster & Oliver, 1990). …”

Section: Resultsmentioning

confidence: 99%

Spatial variability of physical attributes of an alfisol under different hillslope curvatures

Camargo¹,

Júnior

Pereira

2010

Rev. Bras. Ciênc. Solo

View full text Add to dashboard Cite

SUMMARYThe influence of relief forms has been studied by several authors and explains the variability in the soil attributes of a landscape. Soil physical attributes depend on relief forms, and their assessment is important in mechanized agricultural systems, such as of sugarcane. This study aimed to characterize the spatial variability in the physical soil attributes and their relationship to the hillslope curvatures in an Alfisol developed from sandstone and growing sugarcane. Grids of 100 x 100 m were delimited in a convex and a concave area. The grids had a regular spacing of 10 x 10 m, and the crossing points of this spacing determined a total of 121 georeferenced sampling points. Samples were collected to determine the physical attributes related to soil aggregates, porosity, bulk density, resistance to penetration and moisture within the 0-0.2 and 0.2-0.4 m depth. Statistical analyses, geostatistics and Student's t-tests were performed with the means of the areas. All attributes, except aggregates > 2 mm in the 0-0.2 m depth and macroporosity at both depths, showed significant differences between the hillslope curvatures. The convex area showed the highest values of the mean weighted diameter, mean geometric diameter, aggregates > 2 mm, 1-2 mm aggregates, total porosity and moisture and lower values of bulk density and resistance to penetration in both depth compared to the concave area. The number of soil attributes with greater spatial variability was higher in the concave area.Index terms: soil-landscape relationship, geostatistics, semivariogram. RESUMO: VARIABILIDADE ESPACIAL DE ATRIBUTOS FÍSICOS DE UM ARGISSOLO SOB DIFERENTES CURVATURAS DO RELEVO

show abstract

Statistical Methods in Soil and Land Resource Survey.

Cited by 247 publications

References 0 publications

Spatial characteristics of cadmium in topsoils in a typical e-waste recycling area in southeast China and its potential threat to shallow groundwater

Spatial characteristics of cadmium in topsoils in a typical e-waste recycling area in southeast China and its potential threat to shallow groundwater

Geoestatística no estudo de modelagem temporal da precipitação

Spatial variability of physical attributes of an alfisol under different hillslope curvatures

Contact Info

Product

Resources

About