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The study region lies in 34°0′~34°40′north latitude, 105°30′~106°30′east longitude. The relative height is 500~100m. The region lies in intermediatal zone from southern part of warm temperate zone to the north part of subtropical zone and from Qinzang plateau to Loess plateau to Sichuan basin. The climate is warm and moist, most of the region is continental monsoon climate , the annual temperature is 7~12℃,the extremely low temperature is -23.2℃,the accumulative temperature of≥10℃is 2444~3825℃,the annual rainfall is 460~800mm and it focuses in July, August and September,the rainfall in spring and autumn accounts for 70~80% of rainfall of all the year round and it changes heavily annually; the annual evaporation is 989~1658mm, the relative humidity is 68~78, the annual sunlight is 1520~2313 hours, the unfrosted day is 120~218days.The zonal soil of region is the gray-cinnamon soil in north of Qinling and the yellow-cinnamon soil in south of Qinling; the soil distribution is distinct in perpendicularity, they are calcic cinnamon soil, alpine cinnamon soil, alpine luvic cinnamon soil, alpine brown soil, alpine dark brown soil, alpine meadow brown soil, alpine meadow soil, sub-alpine meadow steppe soil from low attitude to high attitude on north slope and they are yellow cinnamon soil, yellow brown soil, alpine brown soil, dark brown soil from down to up on south slope. The thickness of soil is 30~60cm, the soil is humidity, PH is 6.5~7.5 and its texture is soil, the nitrogen content is modest, the phosphor and kalium content are low.The paper studies the biodiversity characteristics, the relationship of the biodiversity and ecological process of community. I get the conclusion through plenty of field survey and data analysis.(1)Patrick abundance index R was 12.464, Shannon-Wiener index H′was 2.005,Pielou index Jsw was 0.825, Simpson index C was 0.227; Through the comparison between herbs layer, shrub layer and the tree layer: for the diversity index, the shrub layer was greater than the herb layer, while was larger than the tree layer; for the uniformity index, the tree layer was larger than the shrub layer, while was larger than the herbs layer; (2) The correlation analysis shows: elevation, slope are main factors which affect the biodiversity pattern in the research region. (3)As the development of community, diversity and abundance index have the similar variation. Conversely, that of evenness and dominance is different. It showed the different significance on ecology. (4) The community , which is built with quercus aliena var. acuteserrata species ,which belongs to is stable. Compared with the earlier studies, the results proved that, the implementation of " tian bao project" is scientific and effective.
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