| Choosing Huoditang teaching experimental forestry station as the study object, which located in Qinling Mountain, the pristine forest landscape pattern of this area is studied, and the general trend of biomass per unit area changing with the environmental elements gradients is also analyzed. In this study many data are used such as the aerial photographs taken in the 1950s, the forest phase maps and the forest management information through detailed investigation. The principle of the four orders classification for forest landscape is applied and the maps of four orders landscape classification are plotted. Supported by the GIS software and the principles, methods and index systems of landscape ecology ,the following conclusions are arrived in this study.The general trend of the relief in the study area can be summarized briefly. The gradient in the lower altitude area is steeper than that in the higher altitude area. In the low altitude areas, the slopes facing the north and to the north are steeper than those of facing the south and to the south; but the condition in the high altitude areas is just opposite to that in the low altitude areas; the range of gradient diminishing is large in the northern direction from low altitude to high altitude, but the slopes facing the south are uniform relatively from low altitude to high altitude.In the study area, the biomass of the slopes facing north is less than that in of gradient facing south in the low altitude, while in the high altitude, the biomass of the slopes facing north is a little larger than that of slopes facing south and the biomass is largest in the middle slope. When the gradient is moderate, the biomass in the low altitude and high altitude is larger than that in the middle altitude; when the gradients are similar, the biomass is the largest in the slope facing south and the biomass in the middle altitude area is less than that in the other altitude areas; when the slopes face the same direction, the changes of biomass in the different slopes have great difference, which are gentle in the slopes facing south but great in the slopes facing north in all altitude areas.According to the actual conditions, the landscape types are classified on four levels. On the first level 7 landscape types and 31 patches are classified; 9 landscape types and 48 patches are classified on the second level; 21 landscape types and 88 patches are classified on the third level; 32 landscape types and 128 patches are classified on the fourth level.Five altitude zones are plotted out in the study area. There are following characters onthe third level of all altitude zones: the landscape specializing Pinus tabulaeformis and Quercus aliena as predominant genera is in predominant station and which belongs to Pinus and Quercus forest zone where the elevation is lower than 1700 meters; all landscapes types distribute relatively uniformly and perform some transition in the zone which elevation is among 1700-1900 meters; the landscape specializing Populus davidiana and Betula albo-sinensis as predominant genera is in predominant station and Populus davidiana is predominant , which belongs to Betula forest zone where the elevation is higher than 1900 meters; there appear Picea forest landscape and Abies forest landscape in the zone where the elevation is higher than 2100 meters.Zone filled with forest is the matri-landscape in the study area and other landscape types inlay in it. The scales of the patches are all about 100 hm2 in the landscapes unfilled with forest like sparse forest ,young forest and shrubwood. Pinus tabulaeformis forest has the largest scale of 57.6 hm2, and other kinds of forestry have the scales above 30 hm2 among the fourth classification. All kinds of mixed forestry have more compound shapes than pure forestry.The study on the bordering degree of landscape shows the following results: the frigid-temperate conifer forestry border greatly the defoliate-latifoliate forestry; the bordering degree among patch of the artificial landscape elements is...
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