Chi Chun-ming;Changwei Zhao;Xiaoxin Sun;Zhichun Wan

Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130012 (China);Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130012 (China; Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130012 (China);Graduate University of Chinese Academy of Sciences, Beijing 100049 (China)

esp;sare;soil;sar1;the songnen plain;sa

Soil exchangeable sodium percentage (ESP) and sodium adsorption ratio (SAR) are commonly used to assess soil sodicity. Correlation between ESP and SAR of saturated pasted extract (SAR(e)) or of 1:5 (m:m) mixture soil to water (SAR(1:5)) has been documented to predict ESP from SAR. However limited studies have been undertaken to model soil ESP based on soil SAR in the Songnen Plain, Northeast China. In this study, 117 soil samples were used to predict ESP from SAR(e) and SAR(1:5) of salt-affected soils in western Songnen Plain. Soil ESP was highly related (r(2) > 0.76, P < 0.001) with SAR(e) and SAR(1:5). ESP of salt-affected soils in the Songnen Plain could be predicted using a logarithmic regression equations of ESP = 10.72 . ln(SAR(e))-15.36 and ESP = 11.44 . ln(SAR(1:5)) + 5.48.