Studies On Soil Adaptability And Soil Management Techniques For The Larix Olgensis Plantation

Based on the extensive reviews of the relevant researches, the key techniques of soi I management for cultivating Larix olgensisplantation were deeply studied using the methods of investigating researches and experiment analysis.It is to determine the best soi I conditions of Larix olgensis plantation by researching the relationship of the soil environment conditions to plantation productivity. These index are not only the criterion of choice the best site for Larix olgensis plantation, but also the standard of checking the decline of the current forest productivity.By contrast test, the soi I management techniques of maintaining the current soil productivity and promoting the plantation productivity were put forward, which supply scientific foundation and practice methods for cultivating Larix olgensis plantation. Ploughing can degrade the temperature of the soil surface, enhance the temperature of the deep layer, and promote the diffusivity of the soil temperature , the totall voidage , capillary maintaining water quantity and the maximal maintaining water quantity , and degrade the soil bulk density . Ploughing can accelerate the growth of seedling root system, develop the root systems further, promote the stands growth , and there is a growth effect difference by different ploughing pattern or ploughing depth, the young trees tilling can enhance the totall forest soil voidage , capillary maintaining waterquantity and the maximal maintaining water quantity .and degrade the soil bulk density . And the correct young trees till ing can promote the height growth of the young tree at 44. 18X, and different till ing way or tilling times induced the difference of young tree growth. According to scarce fertilizer tests of the young Larix olangsis tree planted in sandy soil, the critical value of the scarce nutrition symptom insoi I and needle leafage of the young Larix olensis plantationwere coneluded. According to the exterior symptom of the scarce nutrition symptom and the results of the nutrition diagnose , the scarce sort of fertilization canbe determined, and the fertilizer quantity was accounted according to the difference of the nutrition diagnose value in the soi I and needle leafage to the critical value of two correspond standard, the results were obvious for the times fertilization test. Ploughing for the middle age forest can degrade the soil bulkdensity, advance the total voidage, the content of organic matter and quick result N. can speed up stand growth , and the different effect with the different depth of ploughing . Which burying the needle leafage into soil can promote the soil fertility, such as the content of quick result N, P and K. the effect changes with the types of the needle leafage and depth buryed. is The sprinkled lime into soil of middle age forest can degrade the soil acidity and promote the forest growth.