Studies On The Nutritional Modifier On The Melioration Of Saline Alkali Soil In Western Region In Jilin Province

The saline alkali soil in Jilin province was formed under semiarid and semi moist weather which was distributed in bai cheng region. And the western grassland is the important animal husbandry base in Jilin province. So as far as the development of western animal husbandry and the goal of becoming an ecological province is concerned, it is of important significance that people turn the saline alkali soil into arable soil.The article summarized the newest progression of meliorating the saline alkali soil and on this base ,we used the saline alkali soil in western region in jilin province as object and systematically studied the meliorating result of the nutritional modifier from physical, chemical, ecological character through field experiment and potting experiment. We used many fertility indexes to evaluate the meliorating result synthetically, studied the soil fertility by mathematical method (cluster analysis) and got good result.In the experiment, it proved that the repetitiveness, reproducibility, comparability of the 2.0% (NH₄) 2CO₃ was better than the original method through repeated experiments. The result of it was equal to the sum of water soluble sodium and the exchangeable sodium and it had better precision and accuracy. The 2.0% (NH₄)₂CO₃ could be chosen as the probational measurement of total alkality.The result showed that different nutritional modifiers had different effect on the physical character of the soil, which could be obviously seen from the change of the bulk density and 1⁰.25mm microaggregate. In the same modifier, as the increase of the using level of calcium activator, the bulk density showed a descending trend gradually and the microaggregate showed an opposite trend gradually. The descend of the bulk density showed that compact , bad structure soil became loose. The improvement of 1 0.25mm microaggregate showed that the soil granule structure was ameliorated and it formed a good soil granule structure which fits for the growth of the plant. The soil fertility was improved.In amelioration of the chemical character of the soil, different treatments had different effect. In the same modifier, as the increase of the using level of activator, the pH, total alkalinity, exchangeable sodium dropped quickly, which was very obvious. But as far as the treatment that had not calcium activator is concerned, the physical and chemical character of the soil is same to the original soil, which showed the activating effect of the calcium activator.This method had little effect on CEC because CEC is determined by the number of cosmid and the kind of the clay mineral, so there was not significant difference among the treatments. Furthermore, perhaps due to short time, there is not significant difference among the improvement of the enzyme activity and its nutrition in the soil. There was not significant difference among the treatments.In the experiment, we used the phosphogypsum and calcium activator as the modifier. The mechanism maybe lies in that activated calcium was combined with carbonate, which eliminated the poison of carbonate when the phosphogypsum and calcium activator were used together. And the phosphogypsum supplied the Ca2+,which could promote the elimination of the exchangeable sodium and carbonate. The microaggregate was formed quickly and the alkali soil began to move to the good direction, which benefits the growth of the plant.We used the cluster analysis to evaluate the soil fertility after the of the alkali soil and divide them into 5 kinds, which was the following : I including 1 * 5 > 8? 6 that was bad effect method ; II including 4, 7that was worst effect method ;IIIincluding 2, 3* 9that was better effect method ; IVincluding original soil; V including black soil. And we concluded that number 2 was the best treatment in this experiment after combining it with the result of the potting experiment. What is more, the result of the potting experiment was coherent to the result of the cluster analysis, which proved the success of the cluster analysis on the experiment. So it is of great potential and value to use cluster analysis in the study of soil fertility.