Issue Study Of Land Use And Land Cover Change

The thesis is based on the international study topic of Land Use and Land CoverChange in light of systematical cases research. The study area is mainly in HeiheRiver Basin--Zhangye,Linze, and Gaotai. Why the area is chosen as study area? Thereare some following reasons: on one hand, Heihe River Basin has an ideal study areafor geographical research,'geographical complex'it includes Qilian Mountain, HeiheRiver—the second biggest inland river in China, oasis, deserts etc. On the other hand,the study area has serious ecological and environmental issue, like oasis areadeclining, desertification, soil degradation, deforestation, etc, which caused by thescare of water resources. Last but not least, the study area is a very vital agriculturalbase feeding up hundreds and thousands of local people.The structure of the thesis as follow:The first chapter is focus on illustration of international research hot topic,background, history; key issues of land use and land cover change.Primarily,the second part analyzed the driving forces of research according tothe first part mentioned, the study area is Middle Reaches of Heihe River (Ganzhou,Linze and Gaotai three-county) land use and land cover change and the drivemechanism of the driving forces research. Using 25 years data, combined with fieldinvestigation and field surveys between 2005 and 2006, and analyzed the localgeographical basic data and policies of socio-economic data, to clarify the factors andmechanism of LULCC in the study area. The methodologies are correlation analysis,principal component analysis and regression analysis. And calculation is conducted inthe platform of SPSS 13.0. The results showed the first principal component, thesecond principal component and the third principal component of the contributionrate are 50.501%, 17.819% and 17.480%, respectively. This reflects the complexityof land use and land cover change drive factor in which social and economic drivingforces in the Middle Reaches of Heihe River land use and land cover change hasplayed a leading role, whereas the natural driving force relatively has played a smallerrole. In the drive mechanism, the implementation of the'Western DevelopmentStrategy', and the policy of'Creating Beautiful Mountains and Rivers in Hexi area',as well as policies such as'Returning Arable land to Forests and Grasslands', the process of urbanization is accelerating, which speed up a variety of land use and landcover type changes. In addition, the local population also plays a greater role in landuse and land cover change. Over the past 25 years, the population increased by20.95%. Population growth and changes of arable land have a clear correlativerelationship, the correlative coefficient shows 0.622. Decreased effectiveness oftraditional farming also contributed to land use and land cover change. Prior 2007, thestate did not exempt agricultural taxes, the traditional farming profit declined year byyear due to the increasingly rise prices of agricultural cost, which, in turn, madefarmers adjust the agricultural structure based on market price changes.In the third part, the temporal and spatial change of land use and land coverchange was analyzed using Remote Sensing and Geographic Information Systemaccording to the hot topics of the international land use and land cover change. Thestudy area is Linze Ganzhou. Satellite data is from the NASA satellite imagesDatabase between July 1987 Landsat 5 TM and the August 1999 Landsat 7 ETM +.The calculation and interpretation are conducted by ITT ENVI 4.5 and ESRIArcGIS 9.3. Finally, the study area to be classified into a variety of landscapes, andproduced a landscape ecological map based on the principles and theories oflandscape ecology.The foci of the forth part are project the future (5-50 years) possible change ofland use and land cover. The research approach is Markov Prediction Model. Theources of data is from the land detailed investigation data in Hexi during 2002, 2003and 2004. Model of computing is conducted in the well-known mathematicalsoftware --Matlab 7.0. The results show that: (1) From 2006 to 2010 , cultivated orarable land will transfer into garden, woodland, grassland and buildings. (2) Thesharply changed land use type is forest. As the prediction matrix results shown, thearable, grasslands, pastures, and garden will transfer into forest.Finally, the issues and results of conducting research in the land use and landcover change were summarized.