Spatio-temporal Analysis Of Mangrove Along The South China Sea For 30 Years

Mangrove ecosystem can provide abundant fishery resources and ecological services for human society.The development of the global coastal zone is becoming more and more intense.The overdevelopment of some coastal areas has led to a great deal of degradation or disappearance of mangrove forests growing on land and sea.It has seriously damaged the mangrove ecosystem in the costal region.Thus,it is necessary to find out the growth condition and global spatial distribution of mangrove ecosystems around the world.The coastal around the South China Sea is one of the most important mangrove growing areas in the world.The aims of this paper are exploring the spatial distribution characteristics and temporal and spatial variation trend of mangroves.In this area.Thesis is studied based on above mentioned aims.Firstly,by using the remote sensing images of Landsat series satellites,we used the methods of computer automatic classification and manual interpretation to extract mangroves in three periods of 1987/2000/2016.Secondly,based on the above interpretation results,the spatial distribution characteristics and dynamic changes of mangroves in different countries and regions along the South China Sea are analyzed.Finally,the region of Chinese the Guangxi Zhuang Autonomous and northern Vietnam area were chosen as typical areas to to explore driving factors of adjacent sections form the dynamic changes of mangrove.It can provide data support and scientific guidance for the protection of local area and mangrove management,but also information for the South China Sea mangrove area change driving factor.The conclusions of this study are as follows:(1)Along the South China Sea,the mangrove area decreased as a whole and the rate of decrease was accelerated.The South China Sea coast mangroves in the year of 1987,2000 and 2016 were 13225 km~2,12819 km~2,11783 km~2.The total area was convincing shrinking.Among them,the loss percentage from 1987 to 2000 was 3.07%,and it reached 8% from 2000 to 2016.Apparently,the loss rate increases rapidly.(2)There were the mangrove coverage area of the South China Sea presents.The Indonesia mangrove area of about 5400km~2,accounting for the total area of the study area in 44%,followed by Malaysia(21%),Vietnam(17%),and Brunei and Chinese respectively accounted for less than 2%.(3)There were obvious regional variations in mangrove area around the South China Sea during 1987~2016.Mangrove forests in Indonesia and Malaysia have the largest reduction area,with a decrease of 422km~2 and 368km~2 respectively.The loss rate of mangrove forest in Philippines is the biggest about 177km~2,and the loss rate is 22% in recent 30 years.The mangrove area in China and Brunei area is relatively stable.(4)Based on the analysis of mangrove landscape patterns in typical areas,there are obvious differences in patch characteristics of the mangrove,and the ecology of Guangxi section of China is more fragile and vulnerable to interference.Chinese section of Guangxi mangrove patch area small,high degree of fragmentation,patch shape is regular,closer to the square,the disturbed degree;and the north and south section of mangrove area,low degree of fragmentation of plaque,plaque showed a ribbon or strip distribution,less interference.(5)Basd on the analysis of the driving factors of mangrove change in typical coastal areas,it is found that human activities are the main drivers of regional mangrove changes,and show temporal and spatial differences.Mangrove of China section of Guangxi is mainly affected by the influence of breeding and artificial dike during 1987 to 2000.And artificial surface construction is the main driving factor China section of Guangxi mangrove reduced during 2000 to 2016.North Vietnam coast adjacent coasts,dike farming has been the main driving factors of the regional mangrove reduced,and accelerate with the development of economy.(6)The development model of coastal zone affects the human driving factors of regional mangrove changes to a certain extent.The fishery development oriented coastal zone,dike breeding are the main driving factors to reduce the area of mangrove,such as the north coast of Vietnam;And the coastal zone,port construction and urban expansion,which are mainly based on urban development,are the main drivers of mangrove reduction,such as the Guangxi coast of china.