Effects Of Application Of Improvers And Cultivation Of Alfalfa On Soil Fertility In Saline And Alkaline Desertification Areas In Northern China

In order to explore the application effect of improvers in the saline and alkaline areas of desertification in the north of China and the influence of planting alfalfa on soil fertility indexes,and to provide theoretical basis for scientific and reasonable improvement of saline and alkaline areas.Whether application of a soil conditioner compares the field plot experiment,compares the two kinds of processing between the soil total water soluble salt,soil pH,soil organic matter,total nitrogen,available nitrogen,phosphorus and available potassium content effectively,at the same time,the three alfalfa varieties after 4 years of soil fertility index to study the variation characteristics,the results showed that:1.The soil quality and fertility of the modified plots were generally better than that of the unmodified plots.Specifically,modified saline-alkali soil soluble salt amount and soil pH value were significantly lower,desalting effect significantly,improved the experimental plot of organic matter and total nitrogen content also increased significantly,at the same time,oil available nutrient,soil available nitrogen,available phosphorus and available potassium)are also significant accumulation,higher than that of not applying conditioner test plot.Comprehensive consideration,this saline-alkali land improvement effect is remarkable,for the reasonable improvement of the tumeichuan plain saline-alkali land to provide theoretical support.2.The total amount of water-soluble salt in soil varies seasonally,which is characterized by high salinity in spring and low salinity in winter.Soil pH value decreased significantly after the application of the improver,and then gradually increased with the increase of time.The effect of the application of the improver on reducing the alkalinity of the soil gradually decreased,not as good as the original effect.The accumulation of total nitrogen increased in winter and decreased in spring,and there was an obvious seasonal change.Soil available nitrogen content fluctuates greatly,but generally speaking,it is on the rise.The contents of soil organic matter,available phosphorus and available potassium were accumulated in large quantities in the second year after the application of the improver,and the improvement effect decreased gradually with time.3.After planting alfalfa for 4 years,the total salt content and soil pH in saline-alkali land decreased,and the organic matter and total nitrogen content in soil increased.The content of available phosphorus in available nutrients decreased.The content of available nitrogen and available potassium in soil increased obviously.The Magnum Salt alfalfa improvement soil soluble Salt effect is best,Gongnong NO 1 alfalfa to reduce the effect of the soil pH value,the most obvious Gongnong NO.1 alfalfa increased nitrogen fertilizer increased the effect of soil improvement and best Barricade alfalfa on soil available nitrogen and available potassium content have obvious promoting effect.Therefore,the cultivation of alfalfa in northern desertification saline areas should be improved scientifically and rationally according to alfalfa varieties and changes of soil nutrients.