Study On The Relation Between Geological Background And Plant Diversity Of Gongbu Nature Reserve In Tibet

Gongbu Nature Reserve, lying in the south-east of Qinghai-Tibet plateau, is of greatimportance to the study of forest eco-system, the origin of species and their adaption toplateau environment for its vegetation vertical spectrum and rich bio-diversity. The studyarea also has unique geomorphic units and it is a recorder of geological environmentevolution and a natural lab to study climate succession and the uplift of plateau. These arethe reasons to make the research on the relationship between geological conditions ofplant diversity.Guided by biology, Quaternary, agrogeology, geobotany, quantitative ecology andbased upon field investigation, geographical database and relative literature, the authormade qualitative analysis on the relationship between geological factors and plantdiversity and constructed method to measure geological factors and bio-diversity factors;with the help of3S technique, the author collected information on geological factors,vegetation type and endemic species at different altitudes and then ascertained thesampling scale to carry out the research of geology-plants relationship. At the determinedaltitude, the author studied the quantitative relationships between geology and plantdiversity and deplored into the restricting role and factors of geology to plant diversity byusing the principal component analytical method. On that basis, the paper used GIStechnique to conduct the preliminary research on the definition of the hot spot andperiphery spot and proposed the feasible policies on plant diversity protection. This paperdrew upon the following conclusions: 1. The characteristics of the distribution pattern are as follows: the tectonic movementis the reason to special differentiation and the preservation of relic plants underheterogeneous environment. The vegetation is mainly made up of temperate elements withancient components and young evolution on characteristics. In view of vegetationregionalization, the plants zone can be divided into Niyang River Valley vegetation zoneand Yarlung Zangbo Valley. With clear boundaries and geomorphological units, theGandes landmass-gongbu Jiangda fault uplift is constistent with Gandes landmassmagmatic arc and Yarlung Zangbo combining belts. These features affects the vegetationzones.2. This paper discovered the following regularity of vegetation distribution on basedon lithology: the difference of distribution of similar life form plants is clear on differentlithology. Differences of dominant community and community composition are alsodiscovered between similar ecotype communities on different stratum. The commonco-efficient is low and there is close connection between individual species and somechemical component in the rocks.3. The patterns of horizontal and vertical vegetation distribution show the followingregularity. From northwest to southeast, the Niyang vegetation unit transits to YarlungZangbo unit with the increasing tolerance of drought. The south and north side of thestudy area are relatively dry and the difference in species and vegetation is clear within theunit. In a small scale, the vertical changes of vegetation is much clearer than that oflatitudinal direction zonality and longitudinal zonation. Differences in vertical vegetationdistribution is also clear between Niyang River valley and Yarlung Zangbo River Valley.Especially at the altitudes from3000to4000m, apart from Picea likiangensis var.Nyingchisis and quercus aquifolioides, both areas share little vegetation type in common.4. The corresponding relationship between soil distribution and vegetation distributionpattern is not clear, but to some extent they are mirroring each other: horizontally, thetypes of soil and vegetation become richer from northwest to northeast; vertically theupper limit and lower limit of soil types of vegetation types are consistent.5. We can discover that from the distribution pattern of lighology, soil types andvegetation that the three aspects were consistent to some degrees: the lighology is becoming more complicated and soil types and vegetation is becoming richer fromnorthwest to southeast.6. On the basis of qualitative analysis, this paper construct the information index ofstratum, landform, slope gradient, aspect. By using GIS technique, collecting informationof different altitudes, simulation analysis and checking, the author chose200m as thesampling scale to investigate geology, plant relationship in plateau mountains.7. This paper analyses the geological factors by using PCA and finds that:1) lithology,soil, slope gradient and aspect have high carrying capacity in terms of the first principalcomponent and the influence order is lithologyï¹¥slope gradientï¹¥soilï¹¥aspect. Furtherquantitative analysis shows that vegetation information index and endemic species indexshow polynominal form increase following the increase of lithology information index;the vegetation index shows linear increase with the increase of soil information index;endemic species information index shows polynominal form increase with the increase ofsoil information index; vegetation information index shows log increasing following theincrease of slope gradient and aspect index; endemic species information index showspolynominal form increase following the increase of slope gradient and aspect.2) the highaltitudes have higher carrying capacity which shows the polynominal increase ofvegetation information index and endemic information index following the increase ofinformation index of high altitudes.8. Plants diversity information index and geological factors information index showmonotone increasing simple peak curve and reach their peaks during the altitudes3400-4600m and then show nomotone decreasing with the increase of altitudes, which isconsistent with intermediate zone effect.9. The GIS analysis of geological background information and plants diversityinformation shows that geological background factors have clear prohibiting role upon thespecial distribution of plants diversity. Based on geological background information index,plants information index and indemic plants information index, the author classified thehot zone and periphery zone of protection and proposes utilizing and protective policiesfor plants diversity resources, which are of great importance to the protection ofbiodiversity, the planning and and adjustment of ecological function zone and social economy in Gongbu Nature Reserve...