Comparative research on the impact of human activities on changes in coastline and landscape in bay areas: A case study with Xiangshangang Bay, China and Tampa Bay, USA
Using multitemporal Landsat TM images at a 10-year interval,in this study,we (1) extracted information of spatial location,length,and tortuosity of coastline and landscape configuration,diversity and fragmentation in the bay areas of Xiangshangang Bay,China and Tampa Bay,USA as well from the four 10-year periods from 1985 to 2015;(2) constructed indices of artificial coastline and bay area landscape human disturbance;and (3) explored and discussed the impact of human activities on changes in bay area coastline and landscape types.Our analysis results demonstrate the following five points.(1) In the past 30 years,the length of natural coastline in Xiangshangang Bay and Tampa Bay was shrunk,while the length of their artificial coastline was first elongated and then showed a stable trend.Since there was a difference influence of human activities on coastline and landscape types between the two bay areas,Xiangshangang Bay experienced dramatic changes in parts of coastline geomorphologies and continuous decrease of coastline sinuosity while in Tampa Bay,there was a little change in coastline geomorphologies and its coastline sinuosity was almost unchanged.(2) The intensity of human activities in Xiangshangang Bay was continuously enhanced from 1985 to 1995,and then the degree of enhancement had slowed down after 1995.However,in the time period,the impacted extent of human activities gradually increased and finally covered almost entire coastline in the area.In Tampa Bay area,although the intensity of human activities was enhanced,the degree of enhancement was slow from 1985 to 2015 and the impacted area of human activates was concentrated in several coastal city areas.(3) The average area of landscape patches strongly disturbed by human activities in both Xiangshangang Bay and Tampa Bay generally showed a trend of decreasing from 1985 to 2005.However,during the period of 2005-2015,the mean patch area of landscape disturbed by different degree of human activities in Xiangshangang Bay changed differently,while in Tampa Bay it basically unchanged.(4) From 1985 to 2005,the indices of landscape diversity in various areas of human disturbance in Xiangshangang Bay gradually increased,while in Tampa Bay,changes in indices of the landscape diversity varied.From 2005 to 2015,the change in the intensity of human disturbance in both bay areas was from weak to strong while the indices of landscape diversity in Xiangshangang Bay and Tampa Bay increased first and then decreased.(5) Landscape fragmentation index in different human disturbance areas in both Xiangshangang Bay and Tampa Bay gradually increased from 1985 to 2005 while from 2005 to 2015,in both bay areas,the landscape fragmentation index presented a decreasing trend.
bay coastlinebay landscapecoastline changehuman activitiesXiangshangang BayTampa Bay
NETL
NSTL
万方数据
维普
