The Quantitative Characteristics Of Soil Microbes And Soil Chemical Characteristics Responsing To Human Disturbance In Several Typical For Estlands On The North-Slope Of Qinling Moutains

Soil microbes influence forest ecosystem energy flow and material circulation through participation in litter decomposition, the accumulation of soil nutrients, and migration and conversion . Therefore, It is great significance for the characteristics on the number of microbes and chemical properties in the forest soil to manage the forest ecosystem effectively and prevent soil degradation. This paper Based on the northern slope of the Qinling mountain site conditions similar to the Q. aliena var. acuteserrata, Catalpa fargesii, Pinus tabulaeformis and larix kaempferi ,such as four species typical soil positioning monitoring, Using of exogenous C, N interference (by Shi sugar and urea), New soil mix (different forest humus layer of soil mix)and Laying litter (exchange of different deciduous forest litter) Test,study soil microorganisms, biochemical nature and their response to the various anthropogenic interference On pure needle-leaved forests,pure broad-leaved and mixed woodlands ,Explore the different species of woodland species relationship between soil,Made the following main results and conclusions:1. The comparison with soil microbes and chemical nature of different woodland :among the four species typical woodland soil microbes, nutrient indicators, the rates of nitrogen mineralization and nitrification rates seasonal dynamics obvious,it was significantly higher in Summer than in winter, and it gradually reduced With the deepening of soil. Soil Microbial had the greatest quantity of bacteria, Accounting for 82.15% to 99.27% of total micro-organisms , actinomycosis was followed and fungi at least. The number of soil microbes in 4 species woodland showed: Q. Catalpa fargesii> aliena var. acuteserrata>Pinus tabulaeformis>larix kaempferi; the PH and nutrient content of the soil gross appearance: Broad-leaved forest larger than coniferous forest, Q. Catalpa fargesii> aliena var. acuteserrata>Pinus tabulaeformis>larix kaempferi, with the deepening of soil ,the PH and cation exchange capacity was gradually increasing in the soil of different types of woodland ,however Regardless of coniferous forest or broad-leaved forest, the total nutrients,included N, P, K and soil organic matter content were gradually reduced with the deepening of top-down. The nitrogen mineralization and nitrification rate of Q. Catalpa fargesii and aliena var. acuteserrata was significantly higher than of Pinus tabulaeformis and larix kaempferi.2. Soil microbes and chemical nature with the response of exogenous C, N interfere: compered control, soil microorganisms were increased by 101.22% to 241.65% in four woodland with the individual C interference, individual N interfere with the growth of 35.30% to 358.26%, C, N also interfere with an increase of 215.93% to 945.88%; soil nitrogen mineralization rate increased by 1.54% to 96.63% with the individual C interference to Q. aliena var. acuteserrata, Catalpa fargesii, Pinus tabulaeformis and larix kaempferi, Soil nitrification rate increase of 0.04% to 0.51%,compared to the control, individual N interference nitrogen mineralization rate was increased by 48.21% to 131.58%, Nitrification rates increased by 0.58% to 0.91%; with C, N mixed interference the soil nitrogen mineralization rate was increased by 9.74% to 116.85%, Nitrification rates increased by 0.82% to 2.79% compare to the control treatment3.the responsive principles of laying litter on Soil microorganisms, and chemical nature: In woodland in the four-wide to the principles of Broad-leaved forest mixed coniferous forest, Compared with the control area, Pinus tabulaeformis and larix kaempferi woodland laying the litter of Q. Catalpa fargesii and aliena var. acuteserrata, its soil bacteria, actinomycetes has increased,but, fungi decreased, Q. Catalpa fargesii and aliena var.woodland laying the litter of Pinus tabulaeformis and larix kaempferi acuteserrata an increase in fungi and bacteria, actinomycetes reduced; Broad-leaved forest litter laying on coniferous woodland, PH,organic matter,the total N, P has increased than in control area, but available N, P, K had decreased; coniferous forest litter laying on Broad-leaved woodland, PH,organic matter, total N, P has decreased than in control area, but available N, P, K had increased; after laying litter the Cation exchange capacity in both areas have increased over control; in terms of Pinus tabulaeformis and larix kaempferi, the nitrogen mineralization rates were increased by 17.89% to 198.88% by laying the litter of Q. Catalpa fargesii and aliena var., nitrification rates increased by 0.13% to 4.74%, and laying the litter of Pinus tabulaeformis and larix kaempferi to Q. Catalpa fargesii and aliena var. soil nitrogen mineralization rate decreased 48.55% to 13.33%; nitrification rates decreased 0.73% to 3.21%.4. the responsive principles of new soil mixed on Soil microbes and chemical nature: the whole number of microbes increased range from 8.58% to 95.68% in the ratio of soil mixed Pinus tabulaeformis ,larix kaempferi with Q. Catalpa fargesii and aliena var.to the subject and object 1:3 and 1:1, And Q. Catalpa fargesii and aliena var. with the rate of Pinus tabulaeformis ,larix kaempferi 1:3 and 1:1 oil to the subject and object, the whole number of microbes decreased ranged from 13.10% to 80.35% compared to the control; After any proportion soil mixed,soil organic matter, cation exchange capacity has increased than the control area, Broad-leaved forest soil laying on coniferous woodland, Soil PH, total N, P has increased than in control area, but, available N, P, K had decreased; coniferous forest soil laying on Broad-leaved woodland, Soil PH, total N, P has decreased than in control area,however, available N, P, K had increased; Pinus tabulaeformis ,larix kaempferi with Q. Catalpa fargesii and aliena var. to the ratio of 1:3 and 1:1 mixed, its nitrogen mineralization rate was increased by 16.84% to 73.03% compared to the control area, Nitrification rate increased by 0.12% to 4.88%, Broad-leaved woodlands Q. Catalpa fargesii and aliena var. introduction of Pinus tabulaeformis ,larix kaempferi, and in any proportion of mixed, its nitrogen mineralization rate decreased 39.86% to 66.67%, nitrification rates reduced 0.38% to 2.84 percent.5. The number of soil microbes and soil nitrogen mineralization rate, nitrification rates and soil nutrient indicators have great relevance,Soil total N content and alkaline content of the N significant correlation, Soil bacteria, the total N, available N and organic matter are significant correlation; PH, available P and soil nitrogen mineralization, nitrification rates are related. These show that, increasing soil microbial activity and improving soil nitrogen level, Coniferous forest introduction of broad-leaved forest is Comparing the ideal choice in Create a reasonable Plantation, optimize forest ecosystem, in this paper, larix kaempferi woodland in the introduction of Q. Catalpa fargesii a or aliena var., aliena var.woodlands to introduce Pinus tabulaeformis are the more appropriate.