Land Cover Changes And Their Drivers In Qinwangchuan, Lanzhou, In The Last 40 Years

In this paper, land cover maps in the Qinwangchuan,Lanzhou, in the past 40 years were constructed based on multi-temporal Landsat MSS/TM/ETM+/OLI images using object based image analysis method. On this basis,the drivers for LUCC were proposed and following results were suggested:1. The study area refers to a plateau basin in the Loess Plateau,that is surrounded by mountains. Terrain conditiona take greatly control on the distribution of land cover. The distribution of land cover is a clear law of distribution according to the terrain conditions,Hence appending terrain features from digital elevation model into rule sets improve evidently the efficiency and quality of classification.2. The rule setsfor image classification considering the specific characteristics of different images, make full use of the image object based analysis method providing texture, shape and spectrum, and related aspects of the advantages, in line with the cognitive characteristics of remote sensing image recognition and rule sets.3. The distribution of irrigated land has been expanding from 1384.87 hectare in 1977 to 32,829.66 hectare in 1991; irrigated area decreased from 32,829.66 hectare in 2011 to29,082.51 hectare in 2014.Over the past 40 years, sands area reduced, reducing from41,876.9 hectare in 1977 to 3742.38 hectare in2011. Airport area expanded from 69.52 hectare inl977 to 429.66 hectare in2014.Residential land area from 787.07 hectare in 1977 to 5335.74 hectare in2014. Large Qin cited completion of the project through the water, water resources have been Qinwangchuan rich, increasing the artificial water storage facilities, ponds area from 84.76 hectare in 1991 to 285.48 hectare in2014.Transfer the chart, airport, residential areas has been in a trend of inflows, not outflows through the analysis and comparison of state; for irrigated land, grass, sand inflow and outflow area of the field relatively large changes.the area of grassland in 1977 into 1991 irrigated land area of 1910.73 hectare, sand field in 1977 into 1991 irrigated land area of 3210.21 hectare, irrigated land into grassland in 1977 was only 74.36 hectare.1991 grass outflow into the irrigated land area of 495.7 hectare in 1994,1991 sand Tian Liu out into 1994 irrigated land area of 3151.71 hectare, and the area of irrigated land is not flow out.1994 grass outflow into the irrigated land area of 1317.58 hectare in 2001,1994 sand Tian Liu out into 2001 irrigated land area of 20090.93 hectare, and irrigated land area flow into the grass just 633.19 hectare.2001 grass outflow into the irrigated land area of 2294.19 hectare in 2011,2001 sand Tian Liu out into 2011 irrigated land area of 3345.84 hectare, and the area of irrigated land is not flow out.2011 grass outflow into the irrigated land area of 1667.07 hectare in 2014,2011 sand Tian Liu out into 2014 irrigated land area of 991.08 hectare, and irrigated land area flow into sand field 35.73 hectare, irrigated land into residential land 5908.68 hectare.4. The natural driving force aspect, Qinwangchuan, Lanzhou, mainly alluvial plain, flat, vast area, suitable for large-scale development and utilization, from 1977 to 2014 six images extracted result, the overall development of good southern Qinwangchuan, Lanzhou, Upon the north,1995 Great Qin project lead through the water, water Qinwangchuan, Lanzhou,get rich, irrigated area continues to expand, and sand field area has been reduced; social and economic driving forces regard,1995 80,000 poor immigrants and in 2012 Zhouqu 10,000 immigrants, a substantial increase in population, the corresponding area of residential land have increased; Lanzhou New Area was established after 2012, Lanzhou City, the old industrial "out of the city park," the development of new industry and agriculture, development policy factors such as green ecological zones to promote the development developments, airports and the rapid development of geographic information of New roads and railways also promoted the new district, urbanization and industrialization, resulting in a large number of irrigated land is occupied in development and construction, area is reduced, so that the government digging land reclamation project to reduce the area of grassland, and therefore lead large Qin New development and construction projects and is the main driving force of the country was Qinwangchuan, Lanzhou, information dynamics.