Tóth, T., S. Matsumoto, R. Mao and Y. Yin 1995. Precision of 
predicting soil salinity based on vegetation categories of abandoned 
lands. Soil Science. 160:218-231.

Abandoned saline land on the Huang-Huai-Hai Plain of China are used 
for crops from time to time. The basic question was how precisely 
could the values of soil variables, such as ion concentrations, pH 
and penetration resistance, be predicted to fall into one or another 
range of values based on the presence of specific categories within 
the semi-natural vegetation.
The correlation between sets of soil (mostly chemical) and plant 
(cover percentage) variables in a 100 x 200 m plot was examined by 
calculating canonical variates. The correlation between the first 
canonical variates of the two sets was 0.88, and indicated the 
presence of strong relationship between soil and vegetation.
The semi-natural vegetationof the site was classified either as 
dominated by Phragmites communis or by Imperata cylindrica plant 
species. In this plot these two categories represent overlapping 
ranges of several soil variables. On average the PHRAGMITES category 
occurs at a higher elevation, has a greater salt concentration, 
smaller penetration resistance and, pH than does the IMPERATA 
category. Based on our observations leaching does not affect the 
concentration of bicarbonate ions in the surface soil layers. 
However, as the concentration of other ions decreases and the ratio 
of bicarbonate to other ions increases pH and penetration resistance 
increase in some patches. 
The degree of separability of different soil variables by the 
vegetation categories was inferred from 1) the significance of the 
difference of their means using Mann-Whitney test, and 2) from the 
correlation between the original variables and the linear 
discriminant function of the two vegetation categories based on the 
soil variables. The precision of predicting ranges of individual 
soil variables from vegetation categories was determined by 
one-dimensional thresholding and ranged from 67 to 84%. 
Misclassification by vegetation categories into the range 
assigned to the other vegetation category occurred at least 
twice as often at the borderlines between the vegetation 
categories than inside each category. Vegetation categories 
are considered as an easy and economic way of determining the 
likely success of cropping in saline areas.