Soil sodicity originating from marginal groundwater

Lucerne plots were irrigated with waters of electrical conductivity (EC) = 0.1, 0.8, 2.5, 4.5 and 7.5 dS/m for the summers of 1991–92 to 1994–95. Within those 4 years, soils were sodified at irrigation treatment salinities greater than 0.8 dS/m. Subsequent leaching of salts with channel water (EC = 0.1 dS/m) and rain water (1995–97) reduced surface soil sodicity but not subsoil sodicity. This resulted in increased dispersed clay in the subsoil. Clay dispersion was best explained by exchangeable sodium percentage (ESP) and Mg in topsoils, and by ESP and salinity (TCC or Cl) in subsoils. Ponding of water, following a 46 mm spring rainfall event, increased with ESP of topsoils. Short-term millet yields over the 1996–97 summer were not affected by soil sodicity despite channel water irrigation. However, cumulative pasture yields over 1997 decreased by 25% between high and low levels of residual soil sodicity.

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EFEITO TEMPORAL DA UTILIZAÇÃO DE BIOSSÓLIDO E EFLUENTE TRATADO NA SODICIDADE E SALINIDADE DO SOLO

Irriga ◽

10.15809/irriga.2019v1n1p101-108 ◽

2019 ◽

Vol 1 (1) ◽

pp. 101-108

Author(s):

Dávilla Alessandra Da Silva Alves ◽

Rafael Oliveira De Melo ◽

Jéssica De Lima ◽

José Carlos Coelho ◽

Hélio Grassi Filho

Keyword(s):

Electrical Conductivity ◽

Experimental Design ◽

Sewage Sludge ◽

Potential Risk ◽

Irrigation Water ◽

Mineral Fertilization ◽

Soil Sodicity ◽

Continuous Use ◽

Domestic Effluent ◽

E Mail

EFEITO TEMPORAL DA UTILIZAÇÃO DE BIOSSÓLIDO E EFLUENTE TRATADO NA SODICIDADE E SALINIDADE DO SOLO DÁVILLA ALESSANDRA DA SILVA ALVES1; RAFAEL OLIVEIRA DE MELO2; JÉSSICA DE LIMA3; JOSÉ CARLOS COELHO4 E HÉLIO GRASSI FILHO5 1Doutoranda em Agronomia: Irrigação e drenagem, Faculdade de Ciências Agronômicas (FCA/UNESP), Rua José Barbosa de Barros, 1780, CEP 18610-307, Jardim Paraíso, Botucatu/SP, Brasil. e-mail: [email protected]; 2Engº Agrº, Grupo MNS, Avenida Miguel Petrere, N° 777, Pilar do Sul/S, CEP: 18185-000. Contato: (015) 3278-9000, Sorocaba/SP, Brasil.. e-mail: [email protected] 3Mestre em Agronomia: Irrigação e drenagem, Faculdade de Ciências Agronômicas (FCA/UNESP), Rua José Barbosa de Barros, 1780, CEP 18610-307, Jardim Paraíso, Botucatu/SP, Brasil. e-mail: [email protected] 4Mestre em Agronomia: Irrigação e drenagem, Faculdade de Ciências Agronômicas (FCA/UNESP), Rua José Barbosa de Barros, 1780, CEP 18610-307, Jardim Paraíso,Botucatu/SP, Brasil.. e-mail:[email protected] 5Prof. Dr. Depto de Solos e Recursos Ambientais, Faculdade de Ciências Agronômicas (FCA/UNESP), Rua José Barbosa de Barros, 1780, CEP 18610-307, Jardim Paraíso, Botucatu/SP, Brasil. e-mail: [email protected] 1 RESUMO Objetivou-se avaliar o efeito do uso contínuo de doses de biossólido e efluente doméstico tratado no potencial de risco de sodicidade e salinidade do solo. O delineamento experimental foi inteiramente casualizado em parcelas subdivididas com dez tratamentos e cinco repetições. As parcelas consistiram no uso de dois tipos de água para irrigação (AR- efluente doméstico tratado e AB- água de abastecimento) e as subparcelas pelas doses de biossólido (0, 50, 100, 150 e 200 %), nos anos de 2011 a 2016. Avaliaram-se a condutividade elétrica (CE), pH, Ca, Mg, Na, RAS e PST do solo. Conclui-se que o efeito da adubação mineral (0% - controle) com AB foi semelhante ao uso do efluente na CE do solo para o mesmo tratamento. Doses a partir de 127,4% e 113,2% de biossólido, respectivamente, junto a AR e AB diminuíram o teor de Na+ trocável do solo. Os resultados indicaram baixo risco de sodicidade e salinidade, após cinco anos de uso. Palavras-chave: condutividade elétrica, sódio, reuso ALVES, D.A.S, DE MELO, R. O., DE LIMA, J., COELHO, J.C., GRASSI FILHO, H TEMPORAL EFFECT OF CONTINUOUS USE OF BIOSOLID AND EFFLUENT TREATED IN THE SOIL SODICITY AND SALINITY 2 ABSTRACT The objective of this study was to evaluate the effect of continuous use of sewage sludge and treated domestic effluent on the potential risk of soil sodicity and salinity. The experimental design was completely randomized in split plots with ten treatments and five replications. The plots consisted of the use of two types of irrigation water (treated domestic effluent AR and supply water AB) and the subplots by the biosolid doses (0, 50, 100, 150 and 200%) in the years 2012 to 2017. The electrical conductivity (EC), pH, Ca, Mg, Na, RAS and PST of the soil were evaluated. It was concluded that the effect of mineral fertilization (0% - control) with AB was similar to the effluent use in soil EC for the same treatment. Doses from 127.4% and 113.2% of biosolid, respectively, with RA and AB decreased the exchangeable Na content of the soil. Results indicated low risk of sodicity and salinity after five years of use. Keywords: electrical conductivity, sodium, reuse.

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Spatial Variability of Sodium Adsorption Ratio and Sodicity in Salt-Affected Soils of Northeast Thailand

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.931-932.709 ◽

2014 ◽

Vol 931-932 ◽

pp. 709-715 ◽

Cited By ~ 1

Author(s):

Porntip Phontusang ◽

Roengsak Katawatin ◽

Krirk Pannangpetch ◽

Sununtha Kingpaiboon ◽

Rattana Lerdsuwansri

Keyword(s):

Spatial Variability ◽

Spatial Correlation ◽

Sodium Adsorption Ratio ◽

Descriptive Statistics ◽

Sodic Soils ◽

Soil Sodicity ◽

Class 1 ◽

Salt Affected Soils ◽

Study Sites ◽

Very High

Information on spatial variability of Sodium Adsorption Ratio (SAR) is useful for implementation of appropriate control measures for the salt-affected soils. The major objective of this study was to use geostatistics to describe the spatial variability of (i) the SAR and consequently (ii) the soil sodicity, in areas of different classes of salt-affected soils. Attention was on areas of very severely salt-affected soils (class 1), severely salt-affected soils (class 2), and moderately salt-affected soils (class 3). For each class, 2 study sites were chosen, totally 6 sites were taken into consideration. In each site, 100 soil samples were collected at 0-30 cm depth according to the stratified systematic unaligned sampling method in the dry season of 2012, and analyzed for the SAR in the laboratory. Descriptive statistics and Geostatistics were applied to describe the variability and spatial variability of SAR and soil sodicity, respectively. The result revealed very high variability of SAR. Descriptive statistics showed the CV values of ≥ 35% for every site of every class. When using semivariogram to describe the spatial correlation of SAR, it was found that in 3 study sites, the semivariogram models fitted well with the corresponding semivariogram samples indicating spatial correlation of SAR in the areas. In these cases, the Ordinary Kriging was applied to generate soil sodicity map. The relatively short range values especially for class 1 indicated very high variation of SAR. However, for the other 3 study sites, the linear models were fitted indicating no spatial correlation. Consequently, Trend Surface Analysis was applied instead. According to the soil sodicity maps generated in this study, the areas of class 1 were entirely occupied by strongly sodic soils. For classes 2 and 3, the soils in all study sites belonging to these classes included normal and slightly sodic soils of different proportions. Furthermore, inconsistency of the spatial variability patterns of SAR was found even in areas within the same class of salt-affected soils. As a result, prior to the intensive management of this problem soil in a particular area, investigation on the spatial variability pattern should be performed

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