Synthetic Study Of Land Use/Cover Change In Typical Area In Hanjiang River Basin, Guangdong Province (China)

The Shantou Special Eonomic Area and the developing Meizhou City lie in the Han Jiang river Basin, where heavily live the famous Hakka culture and the Chaoshan culture. Since China carried the Open & Reform policy, the land cover pattern of the basin has changed remarkedly. It is considered an ideal place to study LUCC and its entironment effect for small drainage basins in the hill and mountainous areas of South China.Applying the satellite images of Landsat-TM and the integrating techniques of RS, GIS, and GPS, the present study analyzes the processes and driving factors of land use/cover changes in the typical area of the Hanjiang River Basin since the beginning of 1980s, modelling the possible land use/cover changes scenarios in the coming 10 years based on CLUE-S model, and make an evaluation on the entironment effect of the changes ,and evaluates land use sustainable durative and the ecological footprint.It is concluded in the present study that:(1) There is a dramatic staggered change. From the year of 1986 to 1996, the absolute change extent obey the following sequence: no use land > forest land > build land > cultivated land> water > grassland; and from 1996 to 2006, no use land > build land > forest land > cultivated land> water > grassland. Over the past 20 years, no use land > build land > forest land > cultivated land> water > grassland.(2) There is a great difference of all kinds of land changes.From the year of 1986 through 2006, the cultivated land continued decreased. The forest land kept on expanding over the past 20 years with the 1996s as a rapid increasing period, in 1986, the area percentage of forest land is about 71.26%, and 71.76% in 2006. The area percentage of grassland increased from 0.11%,0.12% to 0.18% respectively in the year of 1986, 1996, and 2006. Since 1996, grassland experienced an obvious increase.The percentage of which in the catchment increased from 5.04% ,5.02% to 5.17% respectively in the year of 1986, 1996, and 2006. The area of build land kept on going up with the percentage of 4.97%, 5.75%, and 7.26% respectively in the year of 1986, 1996, and 2006. No use land experienced considerable decrease in 1986 and 2006. (3) There exist obvious spatial differences in land use/cover change. It exhibited mainly between hill and mountainous area (Meizhou city) and delta plain area (Chaoshan), and also within hill and mountainous area and delta plain area with different human-disturbed characteristic.(4) The change of land use and land cover is result of together operation of all driving factors. Except physical driving factors, over the past 20 years, the change of land use and land cover resulted mainly from economic development, population increase, income increase of local people, market and price,advances in agricultural technology, relevant land policies, as well as economic institution change.(5) Applied CLUE-S model to make a satisfying modeling and prediction on land use/cover change in Hanjiang river basin is found that the forest land and grassland would experience an obvious increase, but no use land and cultivated land decrease greatly under ecological security target scenario; and grassland and forest land would decrease with no use land expanding under food security target scenario; urban land would greatly expand by occupying good cultivated land under economic development target scenario; the all-sided development target scenario could balance the damands of economic development, ecological protection and food security, under which land use change would be more reasonable.(6) The landscape of the Basin tended to become more fragmentized. From 1986 to 1996, the landscape of Hanjiang River Basin tended to become more fragmentized. The patches, in general, became smaller, more even, and less complex. The Ecological Value Index (EVI) of the whole catchment grown upon from 6661 to 6687. From 1996 to 2006, the catchment landscape became more fragmentized as before, and the amount of patches increased, and the average size of patches increased. The patches became more complex with Ecological Value Index rising from 6687 to 6783, as shows that the ecological situation of the catchment was being improved.(7) The appraisal to Shantou's land utilization sustainable indicates that: (1) land use sustainable take on infirmness sustainable, index of land use sustainable lay between 70 and 120. (2) from 1994 to 2000, index change of land use sustainable is about 87 and is ascend from 1994 to 1998, and is descend from 1998 to 1999, and is ascend from 1999 to 2000.(8) The appraisal to Meizhou's ecological footprint indicates that the observation of the ecological footprint demand,supply and deficit of Meizhou's is under the countrywide average. In 2004, the ecological footprint demand of Meizhou city is 1.1174hm²Â·cap^-1, while the ecological footprint supply is only 0.70634hm²Â·cap^-1, the ecological deficit is 0.4111hm²Â·cap^-1, the total ecological footprint is 4.28×10⁶ hm². The ecological footprint deficit of Meizhou's increased from 0.177 hm²Â·cap^-1 to 0.411 hm²Â·cap^-1 from 1996 to 2004. Furthermore, the per capita ecological deficit reveals that the relationship between man and land is more intense. Eco-zoology system of Meizhou get along with unsustinable relatively.Included in the major initial scientific contributions are the following:(1) The study fills up the gap of LUCC regional cases in south wet-hot hill and mountain areas of middle-sized basin. The paper systematically studied the processes, driving forces, spatio-temporal modeling, and made a landscape ecological appraisal, land sustainabl estimate and area sustainable estimate on the land use/cover change over the past 20 years, which deepened understanding of entironmental problems as water and soil loss in south wet-hot hill and mountain areas of middle-sized basin.(2) The integration of quantitative calculation and qualitative analysis effectively revealed the dynamic mechanics of driving factors for the land use/cover change in Hanjiang River Basin. Under the all kinds of physical factorse driving, the paper emphasized the synthesis driving mechanism and interosculations analysis of single societal, and economic factor, and the interaction among the factors.(3) In the ecological appraisal of effect , land sustainabl estimate and area sustainable estimate of land use/cover change, the paper applies Ecological Value Index (EVI),land sustainable estimate model and the ecological footprint model to make a macroscopic assessment of land use/cover change effect on regional ecological and environmental quality, infection of land use sustainable and sustainable state in area. The case study of Hanjiang River Basin shows that these index can well describe the effect of land use/cover change at regional scale.