Primary Study On Assessing Indicators And Methods Of Soil Quality For HEbei Plain

The study was focused on the arable soil of Hebei Plain. Evaluating indicators and methods of soil quality suitable for Hebei Plain were put forward by investigation and determination of typical soil samples, screening of soil quality indicators and comparation of evaluation methods for soil quality. The effects of fertilization measures on soil quality of Hebei Plain were evaluated. Sustainable measures that are favorite for the maintaining of soil quality were screened out by the proposed methods.The main results were as follows:1. About 17 soil characters were screened out as indicators of soil quality for Hebei Plain. They were soil bulk density, pH, clay content, salt content, organic matter, total N, available P, K, Cu, Zn, Mn, Fe, total Cd, Cr, Pb, Hg, As. Classification standards of indicators for soil quality evaluation were put forward and the situations of soil property of Hebei Plain were discussed.2. The methods and standards for classification and scoring system of soil quality of Hebei Plain were established. The functions for soil quality evaluation with fuzzy mathematic method were selected. The weights of each indicator in the membership value were calculated. Three evaluation methods for soil quality on Hebei Plain were proposed.3. The effects of fertilizer application on soil quality of Hebei Plain were judged of by the three evaluation methods of soil quality. The results showed that the companion of organic and inorganic fertilization improved soil quality soundly, such as chemical N, P with manure, or chemical K with the management of long term crop residues returning.4. Among the three evaluation methods, the fuzzy mathematic method had given a relatively objective result of soil quality. The result from the classification method was the last one for representing the real situation in field. The scoring method had the medium capacity.