Hydraulic conductivity of soils from Pernambuco in response to electrical conductivity and SAR of irrigation water

Revista Brasileira de Engenharia Agrícola e Ambiental

Freire, Fernando J.²  Ribeiro, Mateus R.²  Ruiz, Hugo A.¹  Freire, Maria B. G. dos S.²  Ferreira, Paulo A.¹  Alvarez V., Victor H.¹ 

[1] Universidade Federal de Viçosa, Viçosa;Universidade Federal Rural de Pernambuco, Recife

关键词: sodic soil;    electrical conductivity;    sodium adsorption ratio    INTRODUÇÃO A degradação de solos pela sodificação tem-se tornado um problema cada vez mais freqüente em regiões áridas;    onde a reduzida precipitação não é suficiente para promover a lixiviação e retirada dos sais de sódio do meio;   

DOI  :  10.1590/S1415-43662003000100008

学科分类：农业科学（综合）

来源: Universidade Federal de Campina Grande * Centro de Ciencias e Tecnologia

【 摘 要 】

An experiment was carried out in permeameters provided on vertical soil columns with constant hydraulic head in order to evaluate the hydraulic conductivity of soils with contrasting characteristics, and treated with solutions of different electrical conductivities (EC) and sodium adsorption ratios (SAR). The treatments consisted of nine soils, three EC values (175, 500 and 1.500 mS cm-1) and six SAR values of the irrigation water (0 to 30 for sandy soils, 0 to 25 for medium textured soils, and 0 to 15 for clay textured soils). Initially, an adjustment of the Na:Ca ratio in the cation exchange complex was performed with solutions at concentration of 50 mmolc L-1. The saturated hydraulic conductivity of soil (K0) was measured and the relative hydraulic conductivity (K0R) was determined, considering the maximum average K0 values of each soil as 100%. The K0R values were related to CE and SAR of the treatments, by adjusting the response surfaces. The correlation between K0 and the exchangeable sodium percentage (ESP) showed an inverse relationship between both variables in most of the studied soils. The increment in SAR resulted in the decrease of the K0R. It was not possible to define just one ESP value in order to establish a limit for sodic soils. ESP should be considered together with the EC of the irrigation water, as well as soil properties such as texture and mineralogy.

【 授权许可】

CC BY-NC