Coastline Change And Assessment Of Coastline Functional Carrying Capacity In Fujian Province

Studying the spatio-temporal process of coastline changes and coastline functional carrying capacity makes it possible to understand regional varieties in coastal zone,to explore the mechanism of coastline changes comprehensively,and to reveal the anthropogenic influences on it.It is also helpful to provide data sources for natural costline conservation,coastline restoration and to optimize the process of special planning in coastal area as well as integrate coastal zone management for reference.Taking Fujian,China as an example,delineating coastlines in 2000,2010 and 2020which range from continental shore to island with area more than 5km~2 based on remote sensing images.Spatial distribution and change of Fujian coastline were analyzed from the aspects of coastline length,tortuosity and position.The mechanism of how coastline function pattern change was studied with methods of correlation analysis,regression model and case study,employing socio-economic indicators and related coastline change index.We also evaluated coastline functional carrying capacity with constrints of marine functional zoning.Main results of this study are as follows:(1)From 2000 to 2020,with growth of coastline length in Fujian province,there is an obvious increasing in coastline change intensity and coastline tortuosity.At the same time,coastline here mainly extends in a seaward direction due to artificial construction projects and coastal engineering such as sea reclamation.In terms of spatial distribution,there is a heterogeneity in length and morphology of coastline from Ningde(A city in north of Fujian coastal area)to Zhangzhou(A city in south of Fujian coastal area)due to coastal geomorphology.That means coastline in north area of Fujian province tends to be more irregular and twisting,while south straighter.(2)Natural coastline in Fujian province has been declined and the index of coastline utilization dgree has been improved with artificial coastline increase from 2000 to 2020.Further analysis about varieties of internal function in artificial coastline shows that coastal function of Fujian province has developed from a major function of aquaculture(more proportion)and construction in 2000 to construction(more proportion)and aquaculture in 2010 and to a multiple function in 2020,on account of growth in port and sea reclamation and recession in aquaculture and sea-salt industry.Multifunctional attribute and spatial difference of coastline function in Fujian province has become a trend.(3)Taking relationships between coastline change and socio-ecomonic index into consideration,there has been an increase in the index of coastline utilization degree with urbanization and growth of secondary and tertiary industries,also an increase of coastline change intensity with growth of the index of coastline untilization degree.Meanwhile,changes of coastline tortuosity have influenced index of seaward extension.A case study of Xiamen has proved further relationships between marine industry and counterpart of coastline fuction,deducing the mechanism of how coastline function pattern changes.(4)It is concluded that anthropogenic influence is main factor which reforms coastline in the short run.Coastline function pattern has been effect directly by different strategies for industry development in the system of socio-economic and coastal function evolution.More specifically,spatial discrepancy of natural resourses and sequential implement of industrial strategies in Fujian coastal area have effect the utilization of coastline,resulting in the evolution and development of coastal function pattern in the man-land territorial system.(5)It is also found that coastline functional carrying capacity of Fujian province is in normal condition from 2010 to 2020.Howerver,with the boom of artificial coastline and evolution of coastline functional utilization,there is going to be a mismatch between spatial functions in coastline and marine space within sight.For example,the proportion of coastline with functional overloaded increases from 5.0%to 15.8%in county scale,emphasizing a few of mismatched types such as“Constraction or conservation?”or"To what extent?"in central urban areas or suburbs in coastal area of Fujian where infrastucture construction has been rapidly occurring.(6)Based on evaluation results of coastline functional carrying capacity,the mechanism of mismatch between coastal and marine spatial function was analyzed from aspects of construction and space planning in coastal area.There are obvious land-oriented charcteristics in coastal fuction,which probably makes the function of coastline depend on the way of territorial construction to some extent,while the guide of marinel spatial planning to it is relatively insufficient.Due to differences in planning goal or target of land and marine space and lacks of link between them,marine and land spatial planning isolation has led to mismatch between coastal and marine spatial function.Utilization of coastline and coastline function pattern have undergone dramatic changes with the background of rapid socio-economic development in coastal area of Fujian.Consequently,the nature of coastline,such as morphology,length and position,has changed.What’s more,functional discrepancy between marine spatial planning and land spatial planning has increasingly led to overloaded state of coastline functional carrying capacity.Therefore,it would be inevitably important to strat off spatial planning and integrated coastal zone management,employing land-sea coordination to maintain the sustainable development of coastal area.