| It is the most direct dialogue between people and the nature and human-land conflict represents the greatest conflict between people and environment. Since 1960s with global economy developing rapidly and population explosion mankind has faced three major crises of population expansion, resource shortage and environment changes. As a result of human-land conflict sharpening day by day studies on global environmental change are paid more attention. A large amount of research indicated that Land use-cover change (LUCC) is one of the most important reasons causing the global environment change, and sustainable land use is the effective way of solving problems such as global environment and resources,etc..Highly successful researches on LUCC have been launched home and abroad, making LUCC theory deeper and instructing follow-up studies. But some insufficient still existed. For example studies on special region of not-hot spot were not enough, causing shortages of deepening theory and constructing general model. As the second leading factor of carbon emission carbon effective on village and town area were shortage. Standards and reference of LUCC sustainability evaluation were not uniform and weak in practice. So, it not only had the practical value of special region but also had the value of LUCC theory through adopting uniform LUCC standard, pointing out the unsustainable factor in LUCC and putting forward countermeasure and suggestion according to the regional water and soil resources and social economic development level in a given region.The middle-lower transition region of the Yellow River located in the contact of the second landscape step and the third landscape step, being the trailing edge of Loess Plateau and the transition area between the front hills of Taihang Mountain and the alluvial plain of Yellow River. This district is influenced by the Yellow River deeply. The Yellow River opens up gradually and a large amount of silt begins to deposit. Here is large beach, wetland, and valley alluvial plain and low hill area. The special topography are with different resources of light, heat, water,etc. and unique LUCC conditions. In recent years, the economy grown fast, the land use changed violently and human-land conflict relation was nervous. In this paper Mengzhou City was chosen as the study city. LUCC and driving mechanism were studied deeply through human-land theory, soil theory, land economy theory and GIS and RS technology and resource environmental effect and carbon effect were evaluated. Based on above result land use relative sustainability evaluation of villages and towns was gained and relative land use obstacle factors were given regarding average level of the whole county as "Threshold". Finally, sustainable land use countermeasures and suggestions on middle-lower transition region of the Yellow River were given. The results showed:1) The main land use change in Mengzhou City for the past 20 years was that building area increased year by year, forest and garden area expanded greatly, farm area did not change generally bur with quality dropping, water and un-used area reduced constantly. Changes of the farm land, forest land and garden land mainly located in the town of transition area from loess hills to alluvial plain. Change of building and water beach mainly located in villages and towns along the Yellow River. The relative change rate of every land use pattern in the alluvial plain was great. Farm and building land distributed evenly and other kind of land concentrated in some villages, showing intact pattern for the past 20 years. Comprehensive index of land use belonged to medium and above grade, showing that land use stepped into steady period from developing fast period.2)The analysis on driving mechanism of land use change showed that land use change mainly influenced synthetically by natural driving forces such as landscape, climate, hydrology, soil, vegetation, natural calamity and humane driving force such as population social economic development, technological progress, policy, regional cultural environment.3)The constant completion of farmland drains and irrigates influenced water reallocation and operation courses. In this area water level in hills generally rose by 2-3 meters, but that in the low-lying area in plain dropped, making the salt-alkaline area to be better. Soil improvement methods such as straw returning and basin irrigation from the Yellow River made the water and soil resources environment obviously change better. On the other hand, climate becoming dry in recent years, precipitation in the Yellow River Basin reducing and great incensement on agricultural irrigation water produced new environmental problems like that regional water resource became insufficient, wetland area reduced, groundwater level dropped and sanitary sewage and industry waste water polluted farmland. This seriously influenced the sustainable land use and social economy further development, and became the key point of land use research and management in new period.4) From 1987 to 2007, because of land use change carbon storage in Mengzhou City increased by 99.69* 103 MgC. This showed that carbon effect in Mengzhou City was a weak sink. Because of forest land having high vegetation carbon density and soil carbon density, its area increase played a key role in enhancing carbon sink ability. Large reducing water areas and the increase of building land was the main reason of regional vegetation carbon reducing. So in order to increase the carbon storage of the local land ecosystem and reduce carbon emission policy such as planting trees should be enhanced while controlling building area strictly in the future.5) Land use relative sustainability evaluation of villages and towns was constructed from micro angle through considering spatial heterogeneity of villages and towns, and combining index scheme of natural - economy - safety with that of production - safety - protection - economy - society. The land use high relative sustainability area in Meng town mainly located in the plain area, the low one in the northwestern hills. Spatial distribution of resources and environment shown that northeast area was better and west and south hills areas was worse; spatial distribution of production shown that east plain area was strong and west hills areas was weak; spatial distribution of stability shown that east plain area was good, and west hills areas was bad and south Yellow river beach was the worst; spatial distribution of protective shown that south area was strong, north area was weak and east plain area of high population density was weaker. The economic structure and benefits in the western hills area were generally relatively bad, social structure and benefit were relatively better. And the fact was just opposite in the eastern plain area. From 1986 to 2004 spatial distribution of land use relative sustainability was unchangeable generally, showing that east and south area was good and west and north area was bad. The gap between the highest and the lowest was 0.624 in 1986 and increased to 0.889 in 2004, showing a obvious polarization.6) It was a trend that image was classified under combining multi-source remote sensing data with non-remote sensing data by GIS technology. This was because that multi-source data can overcome the lost or error of series data. Meanwhile land use classification accuracy could be effectively improved using background database or expert knowledge database based upon quantitative data of natural and human factors processed by GIS. In this paper, technological framework of land use information extraction was established using multi-source remote sensing data (TM and CBERS-02B), DEM, slope data, land use map and other geographic auxiliary data. The method of multi-level supervised classification was adopted. First urban building and water were extracted on TM 1-4-5 image. Then TM 3-4-5 image was masked by above classified land for remnant land use information extraction. As to CBERS it was 1-2-4 and 4-3-2 respectively. Finally above each classification was overlapped by ERDAS in order to obtain overall land use map. Interpretation accuracy was improved by establishing background database through GIS technology. First, non-remote sensing information, such as topographic map, soil map, land-use map, transportation map, etc, was integrated as background database. Then land use classifications were overlapped with above database. In the study area dry land spectrums in plain area, hilly area and the Yellow River flood plain were very different and spectrums of habitation in plain and the Yellow River land wash were the same. As for above phenomenon of"same object with different spectrums"and"different objects with same spectrum", expert knowledge database was established based upon correlation between remote sensing image and geographical environment.
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