Research On Land Use And Cover Change In Farming-Pastoral Region In Inner Mongolia Based On GIS And RS

In order to study the impact of human activities on spatial distribution, transformation and the ecological environment of land use / cover in agro-pastoral transitional zone, With Taipusi Qi in Inner Mongolia as the case and its satellite remote sensing data, supported by GIS platform technology, this paper has analyzed the change of land use, land cover and spatial landscape pattern in the past 30 years. Based on the above, the Markov Model is applied in the prediction of land use variation in the following 20 years. The results are as follows:Land use / cover change analysis shows that: from 1975 to 2004, the major land-use type consists of grassland and farmland in the structure land use-type. The farmland dominated in coverage in 1990, while in the other three periods, the grass area led the first place, with forest, water, construction land and unused land in relatively small share. In terms of the spatial changes of land-use types, there was a clear transformation between grassland and farmland. Between 1975 and 1990, the farmland area increased with entrance surpassing exit, in contrast, the grassland area decreased. From 1990 to 2004, the grassland area expanded while the farmland shrank. Land-use change analysis shows that: from 1975 to 2000, comprehensive land use index was in an upward trend, reaching the maximum in 2000. Land-use degree in 1975 was low with the smallest index, indicating the small influence of human activities on the change of land-use types with the low exploitation of the land resources in 1970s. But the influence deepened in 2000. In brief, the land-use extent was in the development period in 1975-2000, contrasting a period of adjustment in 2000-2004.Analysis of the change in landscape-pattern shows that: In the patch-type level, grassland and farmland scapes are the main landscape types in the study area. In 1975, the proportion of grassland plaque was in a dominant position, surpassing the other patch types clearly. In 2000, farmland scape patch density reached the maximum degree with the fragmentation increasing. In 2004, the farmlandscape shape index got the highest with the increase of margins and the reduction of the area validity. At the landscape level from 1975 to 2000, spread index and aggregation index continued to decrease, Shannon and Simpson diversity index showed a growth trend, indicating that during this period the landscape was comprised by a variety of plaque with low connectivity, the degree of landscape boundary fragmentation was increased, the seperation of plaques grew, the complexity of space shape rose, the connectivity of same type patches declined, and the landscape developed in the direction fragmentation and diversification. From 2000 to 2004, as the degree of landscape controled by one or more dominating landscapes rose, the plaque got a good connectivity, showing the feature of reunion trend. The overall landscape fragmentation level reduced, and land-use system developed in the orderly and balanced direction.Reasearch results on soil erosion (water erosion) show that: In the study area in 2007, the soil was slightly affected by water erosion, mainly in a micro-degree, accounting for 77.2% of the area erosion, with the mild-degree covering 14.4%, the moderate-degree 8.3%. Land area eroded to the intense or more extent was small. In the area of slight erosion, the farmland accounted for 19.12%, grassland accounting for 50.47%, woodland 5.74%, unused land 1.84%. Of the mild erosion area, grassland occupied 11.31%, farmland 2.51%, forest land and unused land covering the least. In the moderate erosion area, grassland took 6.44%, farmland 1.81%, forest land and unused land accounting for a very small proportion. Different land use patterns led to different levels of soil erosion. In the study area, farmland is in the highest rate of water erosion with the proportion of 42.87%, contrasting grassland 22.96%, forest 6.52%. The unused land was mainly in the micro-degree in water erosion. On the whole, the way of land-use in Taipusi Qi is beneficial to soil and water conservation.Prediction gained by the use of Markov models in the land-use change in the study area indicates that: In the futural period of time, farmland, grassland, unused land will be slightly reduced each year, forest area will increase, and the change trend of water area is getting stabilized. With the process of urbanization and economic development, construction land will increase in a significant tendency.In short, human activities had the largest influence on ecological landscape in 1990s, primarily for the significantly expanding of farmland in this period. In 1975, grassland was in the dominating place, while farmland area was small, so the land-use was least disturbed by human activities. The extent of land-use is mainly affected by the national land-use policy. Implementation of rational land use policy, environmental management by use of restoring function of the ecosystem itself are the basic way of ecological restoration in the region.