A Research Into Vegetation Changes Of The Mt.Qomolangma National Nature Reserve

Based on the factors such as vegetation distribution types， vegetationdistribution changes， soil， stratum， landform and land use， this thesis attemptsto find the relationship between vegetation changes and other factors by interpretingand analyzing remote sensing images and data in the Qomolangma natural reserve，and draw a conclusion on the relationship among vegetation change，human activity，and Tibet plateau uplifting.According to the MODIS NDVI data from2000to2009，TM and ETM datafrom2000to2007，SRTM DEM data and Geological map in this study area，generatethe pictures of stratum，vegetation cover，DEM，change of NDVI-Max and slope byinterpretation and processing. We can draw a conclusion after analyzing therelationship each picture that the major stratum in this nature reserve are theMiddle-Upper Proterozoic and Quaternary. The vegetation cover on Middle-UpperProterozoic showed a better trend than which is on Quaternary from2000to2009.Most of the Middle-Upper Proterozoic is on the southern slope of the reserve，whichhas the more complex topography，wider range of elevation，and steeper slope.Compare with the Middle-Upper Proterozoic，the Quaternary is on the northern slope，which has the opposite kind of topography，elevation and slope to the southern slope.Due to the topography condition，although the southern slope has the better climatecondition，the northern slope is more Suitable to survive for human beings.Strongly influenced by the wet-Heating stream from the Indian Ocean， thesouthern slope of the Everest has the climatic characteristic of Maritime monsoon.Because of the sufficient rainfall， there is mountain forest ecological system in thisarea. The drought of northern slope was aggravated because of the high Himalayas，by which the wet-Heating stream from the Indian Ocean was cut off and lose much moisture. Continental plateau climate is the main characteristic， semi-arid shrublandand grassland ecosystem are also the main characteristics. The most critical vegetationdeterioration area is the Quaternary of the northern slope， which has the gentleslopes. There are Kobresia Pelouse and Kobresia Meadow， which are capable for theanimal husbandry.The southern slope has the better vegetation change， especially on theMiddle-Upper Proterozoic， vegetation coverage in much of this area was rising.During the process of great Tibet plateau uplifting， many mountains were generatedby strong compression， which also made many north-south folds and faults，exposed strata in this area are old. Although the climate in the southern part is betterthan the northern part， but the complex terrain， relatively large height differenceand steep slopes make it not suitable for human beings to live on. So destructivenessof vegetation coverage of this area is not that serious， and the restoration is favorableaccordingly. There is little series of Middle-Upper Proterozoic in north-east of theDing Ri County and Ding Jie County of the northern part， the major slopes on whichis between15-30°， so the vegetation restoration is relative favorable. It can beconcluded that the Middle-Upper Proterozoic usually accompanies the complexsurface， making the special environment of plant growth and humans lives. Theconsolidation of Quaternary have not completely finished， much of the stratum areloose debris. Due to the gentle terrain， small slope， and small range of elevation，the nice environment is suitable for human beings to live in， causing more seriousdestruction of vegetation coverage and living environment.The reduction of water area was widespread in other areas of the Qinghai-TibetPlateau during the past several decades， deteriorating the existence of MarshWetland. By analyzing the change of lakes in the natural reserve during1990to2006，the area of lakes had decreased after increasing. The area was increasing during1990to2000， the number was also increasing. The melting of the snow on the peaks， tosome extent， was affected by global warming， which made more quantities of lakesand larger area of lakes. After2000， on the contrary， the area of lakes wasdecreasing. The main reason is the destruction of human beings， who did not adoptmeasures to protect the ecological environment of lakes. The abnormal rainfalls andclimate also made this reduction. The vegetation coverage around the lakes alsoreduced in the same time. The rapid reduction is a phenomenon which stronglyaffected by the soil erosion which is the result of vegetation degradation. Thevegetation and water are in independent relationship， if area of water has reduced， vegetation coverage would also reduced， vice verse. So the measure should beadopted to prevent the reduction of lakes by human destruction， the desertificationand salinization should also brought to the forefront. So protecting the environment ofLake ecosystems is imperative.