Study On The Relation Between The Soil And Diersity Of Sharp Tooth Oak In Tian-shui Xiaolongshan

Studied the soil characteristic of the sharp tooth oak community in Xiaolongshan of Gansu province, locate western region of the Qinling mountain, And the relation between soil and community' s function and between soil and community' s bio-diversity. To 30 kinds of plot, 11 kinds of soil index, amount to 902 data, summarize the research area 1.The soil characteristic is shown: (DSoil texture belong to silt, silt loam and clay loam, they are all loam. The soil has good granule structure, it is the soil of a kind of ideal texture and fine structure. (2)Soil organic matter is between 1. 71% (1605m) and 5. 35% (2050 m), most centralized between 2% and 4 %, According to the fertility classification standard, the research area belong to the high fertility place. PH value is between 5.72 (1790m) and 7.90 (1980m), it is the weak acid or weak alkaline. (4)The whole N is between 0.21% (1605m) and 0.56% (2050 m), it is relatively high. (5)The available N is between 18.20mg/kg (1680m) and 346.71 mg/kg (2050 m), relatively centralized between 20mg/kg and 60 mg/kg. (6)The whole P is between 0.026% (1550m) and 0.167% (1940m), concentrate on the range of 0.026% to 0.065%. (7)The available P concentrate between 5ppm and lOppm, it is a medium leve. (8)The whole K is between 1. 5% and 2%, it is higher. (9)The maximum of available K reaches 442mg/kg (1630m), the minimum is 76 mg/kgs (1920 ms), the range is breath. (10)Soil water is between 12% and 16%, is the moist soil. ODAt last, Comprehensive analysis the relation of mutual influence and interaction between the soil organic matter, soil structure, PH value, the whole N and available N. 2.The space-time character of the soil is: (DSpace characteristic: at sunny and shade slope, soil organic matter, PH value, the whole N show the tendency of relatively higher in the low and high elevation and relatively lower in the middle elevation. Available N is stable with the elevation increasing except 1650 m at sunny and shade slope. The whole P and whole K show Fluctuate violently with elevation increasing at sunny and shade slope. Available P and available K are different trend at sunny and shade slope, and it is opposite. (2)Time characteristic: Confirm the development time of the soil according to the development stage of the community. (1)Soil texture transits from silt of middle stage to clay loam of the later and latter stage. (2)Soil organic matter is steady and increase tendency with the tooth oak community development.(3) PH value keeps the same change tendency with the organic matter. (4)The whole N presents: latter stage >Medium> later stage. (5)Available N presents the rising trend with development stage, and the range is extremely high; (6)The whole P is high in medium, and sharply decrease in later and latter stage. (7)Available P is similar to the whole P trend. (8)The whole K is lower in middle period, and increase sharply in later and latter stage. (9)Available K is scattered, the range is extremely high. (3)space-time dynamic characteristic: (1)Middle period, with the elevation increase, soil organic matter and PH value show the tendency of reducing slowly, then rising gradually. Later stage, is steady. At latter development stage, the organic matter and PH value have the trend of straight line rising. (2)In middle development stage, the whole N and available N show opposite tendency with the elevation increasing. The whole P is nearly straight line' s tendency. Available P presents the increase line' stendency with elevation increasing. The whole K is near steady line' s trend, available K presents the trend of " V " type. In latter development stage, with elevation rising, the whole N and whole P present decrease gradually, available N and available P presents rising, and then decreasing. The whole K presents the parabola trend, available K presents the fluctuating trend. In the latter development stage, with the elevation rising, the whole N and whole K increase gradually; available N, the whole P and available P show fluctuating style. The available K is...