Urban Landscape Pattern Research Of Lhasa Based On Landscape Ecology

Currently, urbanization process accelerated significantly in China. In the process, many of the urban question arises, affecting the healthy development of the city. From the point of view of landscape ecology, the root cause of the problem is the city irrational urban landscape elements, which restricts the overall function of the city to play. How layout elements of the urban landscape scientificly, and improve the urban functions is the key to solving urban problems. it is one of the hotspots of landscape ecology.In this paper, the Lhasa City is the area for research. In the support of remote sensing data, GIS technology and the Patch Analyst software, the paper using the basic principles of landscape ecology, computing Lhasa city landscape indices. On this basis, the paper forecasts the construction land requirements of the Lhasa, combining city planning. The paper analysis the current situation in Lhasa urban landscape pattern and make optimization recommendations.Through analysis, we draw the following conclusions:(1)Shannon diversity index of Lhasa urban landscape is 2.10. The Shannon evenness is 0.91. Urban landscape’s fragmentation is high and pattern uniformly. The area of living landscape is largest, with a total of 1537.17 ha and a distribution of "big reunion, small decentralized". Lhasa is carrying the administrative functions of autonomous regions and municipal levels, and many cultural relics. So the area of public land landscape with a total of 1273.27 ha is also more prominent mainly gather in the traditional center of the city. The area of business services landscape is small. It distributes brokenly, scattered along the street mostly. Parkland is the main green landscape, mainly concentrated in the central city. The shape index of traffic landscape is the highest with a number of 5.45. It’s is the corridor landscape of Lhasa, plays the role of the transport corridor. The area of water landscape is small, with a total of 57.27 ha,. Water landscape is composed of North Canal, South Canal, and Liu Shahe, was distributed long and narrowly. The shape index of water landscape is the highest, with a number of 7.09.(2)The ecosystem of Lhasa functions imperfectly. The area of green landscape is sizable with a number of 884.22 ha, but the greenery resources that resident can enjoy is limited. 500 m buffer area within only 707.55 ha, accounting for 13.30% of the total area completed, within the buffer area 500-1000 m for 1272.93 ha, accounting for 23.93% of the total area built. The greenery of the central area and the north area is high, but the east area and west area is low, essentially blindly. The connectivity of corridor landscape is not high. The r index is 0.58, so the net rate is not high. Ring of the α index is 0.37. so the broken end road is too many, especially in the urban fringe areas. It increases the pressure on the downtown traffic.(3)The construction land per capita of Lhasa is high. The demand of midconstruction land are 1411.82 ha. Restricted by terrain, the development directions of urban construction are eastward and westward.(4)The optimization of Lhasa urban landscape pattern from the following three main aspects:①Protect the sensitive urban landscape patches, maintaining the diversity of Lhasa on regional characteristics and culture;②Increase the habitat patches in the urban landscape, to landscape the urban environment and meet the needs of the residents close to nature; ③Improve the connectivity of corridor Landscape and open loop outskirts of the city, to improve the transmission efficiency corridor.