The Disturbance's Impact On Soil Nutrient Pool And Vegetation Diversity In The Bipenggou Ecotourism Area

With the development of national economy and the improvement of people's living standard living, our country's ecotourism flourishes since the 1980s.At the same time, the environment problems brought by ecotourism are increasingly prominent. Many scholars have begun to research on the impact of ecotourism on the environment, and gain a great deal of outstanding achievements which make huge contributions to the healthy developments of our country's tourism. The qualities and developments of ecotourism area depend on soil and vegetation. Also, the soil and vegetation degenerates after they are disturbed, so it is necessary to research on impacts of disturbance, which provide theoretical basis for environmental protection in the ecotourism area. This article is based on the research of the Bipenggou tourism area in the western mountainous area of Sichuan province. It aims at researching on impacts of three kinds of disturbance including trample on the Bipenggou tourism area, constructions of road made of cement in the ecotourism area and burning on the soil physical structures, soil nutrient pools as well as plant species diversities. The main results are as follows:(1) Disturbance changes the soil physical structures, which result in the increase of soil capacity and graved content whereas the decrease of moisture content as well as porosity. Trample has strongly destroyed the structure of topsoil while burning leads the destruct of the whole structure of soil, even it is very difficult to recover. In addition, the degree of destruct of roadside soil physical structure is relatively small.(2) Disturbance enhances soil pH value, which buildups the soil alkalin. The alkaline of travelling path and the topsoil of roadside is higher than that of middle and lower layers(30～60cm), moreover, the degree of soil pH value in the middle and lower layers of burned area is apparently higher.(3) Disturbance is to decrease of the content of soil organic matter, total nitrogen, total phosphorus and available phosphorus, whereas it has little influence on the content of potassium. Trample remarkably reduces the content of topsoil nutrient, so does the burning. The slowdown of roadside's topsoil nutrient content is relatively small.(4) Disturbance decreases the soil's organic matter pool, nitrogen pool and phosphorus pool. The pelagic soil's (0～30cm) organic matter pool, nitrogen pool and phosphorus pool, were significantly higher than that of the lower base of soil (50～60cm). but there is a tendency of transferring down gradually after disturbance.Trample havocs the topsoil's nutrient pool. Burning prominently reduces the organic matter pool, nitrogen pool and phosphorus pool of the subsoil(50～60cm). The soil nutrient pool along road reduces in relatively slow speed.(5) Disturbance alters the composition and diversity of frutex and herbage species, especially decreases them. Arbor suffers from little disturbance. Even if it is exposed to burning, it can gradually return to the original community.(6) Disturbance is gradually changing the direction of plant community succession.The plant population that is able to bear trample and has a strong reproduction ability constantly expands, at the same time, "anthropochory" continue to increase. A large area of plantation along the scenic spots' road heavily degenerates which lead to result that understory vegetation community gradually develops towards the barren-resistance ones.