Dynamic Pattern And Driving Forces Of Land Use/Land Cover Changes In The East Costal Area Of China,the Su-Xi-Chang Region

Over the past decades China has perceived notable land use/land cover(LULC)changes.This has attracted much scholarly attention,chiefly in light of the extensive economic reforms,profound structural changes,and remarkable economic growth.Particularly in the eastern provinces including Su-Xi-Chang region the process of change in LULC is intense.The spatial pattern of LULC change in these provinces isin linewith economic development.Because the eastern provinces enjoy locational and institutional advantages and mass economies,they have attracted bulk of foreign investments and are the leading exporters of Chinese products.Furthermore,for being the country is a member of World Trade Organization has more benefited industrial firms located in eastern China with better access to international markets.As a result the region experienced dramatic economic growth,spatial restructuring,and expansion of construction land that caused remarkable LULC changes,thus led to various environmental and ecological consequences.This study is an attempt to assess the LULC changes,drivers behind the changes,the impact of these changes on ecological systems,and forecasting their future implication on sustainable land management and the ecological economic values of the Su-Xi-Chang region in Eastern costal area of China.Thus,the thesis(1)assessed the spatiotemporal patterns of LULCchangetrend by using time series remotely sensed images and land scape metrics,and explored the distribution of changes across the study area over the past three decades,(2)scrutinized the change in ecosystem service values(ESVs)in relation to LULC changes during the study period and explored the most critically affected ecosystem services function,(3)identified the underlying driving factors contributed for LULC dynamics and considered the relationship between LULC changes and the major drivers,and(4)forecasted and modelled the future changes in LULC,and predicted the subsequent changes in ESVs,to enable the anticipation of future planning policies that seek to preserve the unique natural characteristics and ecological values of the studied landscape.To achieve these objectives for time series LULC changes analysis(1980,1990,2000,2005,and 2010);the study used vectored data sets with 30 m spatial resolution from Landsat reflectance products and DEM of the computer Net Work Information Center,Chinese Academy of Science.Images were geometrically corrected using ground control points and ETM+image as a master and reference image.To identify the agreement in classification consistency and accuracy,effective classification was conducted by using standard procedures(Liu et al.2005).Accordingly,six LULC categories:farmland,woodland,grassland,water body,wetland,and construction land were classified for the studied periods.ArcGIS spatial analysis model was applied to measure variation within LULC types.FRAGSTATS was used to compute the dimension of spatial patterns fragmentation.To analyze the potential socioeconomic driving forces triggering LULC changes a time series socioeconomic data on population,industrial output value,agricultural production(Crop yield),aqUatic products,GDP,agricultural land,and construction land(settlement areas)from 1980 to 2010 were used.Changes in ESVs were assessed by using the areas covered by each LULC category and the modified ecosystem service(ES)coefficients of the corresponding biomes.A coupled CA-Markov model is employed to conduct LULC change modeling.The prediction of changes in ESVs involved the use of the projected area of each of the LULC types and their modified ES coefficients.The main results are as follow:1)In the context of LULC changes,significant spatiotemporal dynamics were examined in the region,whereby construction land dramatically increased with disordered spatial configuration over the other LULC types;remarkably,this growth far exceeded the amount of land converted from construction land to other LULC types.In the past three decades,notably,construction land increased by 359,436 ha,amounting to 285%of the area in 1980,during which it covered merely 7%of the total study area,which rose to 27.80%in 2010.The loss of farmland strongly contributed to the newly emerging construction land,and was followed by wetland and water bodies,respectively.Thus,driven by robust socioeconomic factors,the ongoing growth in construction land was responsible for a large decline in the farmlands,wetlands,and water bodies in the region.In addition,changes in landscape patterns and composition exhibited increased the fragmentation of farmland and wetlands.Thus,the future plans should have to consider the high pressure put on farmland,wetland,and water body categories with high ecological values,which have been losing at higher rate than other LULC types.2)Scrutinizing the change in ESVs in relation to LULC changes and exploring the most critically affected ecosystem services function.The region gradually showed a decrease of 3.42 billion CNY worth of ESV from 2000 to 2010,during which the second round rapid urbanization and industrializations occurred in the region.Of the total decrease 61%was due to lose in the farmland.Farmland combined with water body and wetland accounted for more than 98%of the total ESVs.These three LULC types play major roles in providing ecosystem services;however they are highly threated than the other LULC categories.Food provision was the most affected ecosystem service function,which was reduced by a quarter of its base year value,mainly due to significant loss in farm land.Waste treatment and water supply were the most two ecological functions.Farmland and water body were the ecosystems whose surface reduced the most,and yet,they are the ecosystems with the highest estimated service values.The loss in ESVs of the region worth attention because the loss in total of 3.42 billion CNY with in a decade was far greater than researches in some other areas of the country.The compromise between expansion in construction land and ecological protection must be reached.To accomplish this,the regional land use planning must emphasize the protection of farmland,water body and wetlands.3)Identifying the underlying drivers of LULC changes.Combinations of various socioeconomic factors have induced LULC changes in the region.Population growth and economic development,urbanization and subsequent construction land expansion,and industrialization were found to be the major change drivers.The growth of population over time increased the demand for residential areas,and hence,large areas of farmland were converted for settlement construction.Furthermore,to achieve more economic benefits from their farmland,farmers practiced profit oriented farming systems,particularly by converting their farmland into artificial ponds for fish production.Similarly,the rapid industrialization consumed large areas of farmland.Because of an all-around rapid industrialization since 2000,to support the manufacturing expansion,less attention was given to agricultural land.As a result,urban associated industrialization became an essential driving force of LULC changes,thereby predominantly decreasing the arable land category.Given the current trends of socioeconomic drivers in the Su-Xi-Chang region,increasing pressure on LULC is causing an alarming change in farmland,water bodies,and wetland.The change in farmland involves decreases in both area and production and may impair the ecological functions that support the human dominated environment and result in a decline in food production.Therefore,policies to achieve long term sustainable development must address the effects of these drivers on LULC and ecological development.4)Forecasting and modelling the future,2020,LULC change,and predicting subsequent changes in ESVs.The trend of LULC changes in the region reveal that the changes experienced in the recent past are likely to continue in the fixture,2020.Even though their rates of change(gains/losses)are comparably less than in the former periods,the predicted LULC change shows that the farmland,water body,and wetland categories will continue to decrease.These LULC types have been largely replaced by construction land.In 2020,with a more than three-fold increase over its base year area and covering greater than 31%of the total study area,construction land will become the dominant LULC next to farmland(34%).Thus,the ongoing trends of change have placed pressure on LULC classes with significant ecological values,which could result in losses in ES provisions of the region.The predicted ESV results reveal that each LULC category exhibited different trends of changes,in which the values for farmland,wetland,and water body were reduced,whereas the values for woodland,grassland,and construction land showed an increase.Over the study period,the total ESV of the region decreased from 59.6652 billion CNY in 1990 to 52.2737 billion CNY in 2020,mainly because of the loss of farmland,water body,and wetland.The water body class produced the largest proportion of the total ESV(73%),and combining water body and farmland accounted for more tban 90%of the total ESV,indicating that the two LULC categories play a role in providing the highest ESs in the region.Water supply and Waste treatment were the top two ecological functions,accounting for more than 68%of the total,mainly provided by water body and wetland cover types,followed by woodland and farmland.Even though water body and farmland are the dominant LULC classes providing a major share of the ESVs,these two categories are becoming highly degpraded including the wetland.For sustainable management,a reasonable land use plan should be made with an emphasis on controlling construction land(industrial,comlercial,residential)encroachment on farmland,wetlands,and water body.Furthermore,the rules of ecological protection should be followed in LULC management to preserve ecological resources and benefit society.Thus,decision makers should plan altermative conservation activities to enact improved LULC management practices for sustainable and balanced ecological protection.5)Uncertainties in LULC change analysis and ES assessment.Sources of uncertainty in LULC change analysis were considered and are basically come into existence owing to landscape heterogeneity,natural spatiotemporal variability,anticipatable landscape dynamics,and scaling effects.In LULC change modeling basic sources of uncertainty mostly accredited to model structures,model assumptions,the consequences of spatial and temporal scaling,and lacking model inputs.However,in ES assessments sources of uncertainties frequently originated from the lack of knowledge of biodiversity's function in generating ESs and goods;problems of development and integration of monetary valuation strategies and the respective methodological fundamentals.In general,as the LULC change analysis and spatial ES assessments are highly necessitated for landscape management and planning,revealing and dealing with related uncertainties is an important and current issue.Thus,beside applying and improving the approach reviewed and presented in oul work to move beyond these preliminary and illustrative few initial works,a determined research enbort is thus needed to develop new techniques or innovative ways of using existing techniques to create capabilities of providing ideal outputs of umcertainty analysis to help decision making with uncertain information on environmental and ecological management.