广西海岸潮间带互花米草遥感监测

摘要

[目的]对广西海岸潮间带入侵物种互花米草(Spartina alterniflora)进行遥感监测,查清互花米草分布区域.[方法]以2016年GF-1号高分辨率卫星影像为数据源,利用遥感技术与野外勘查相结合的方法,对广西互花米草扩散现状进行监测和分析.[结果]截至2016年7月,广西海岸潮间带互花米草分布面积为686.48 hm2,斑块数5191个,平均斑块面积为0.13 hm2,最大斑块面积为47.24 hm2(位于丹兜海海域滩涂).此次调查结果显示互花米草面积比引种时期增加了685.54 hm2,面积增长了729倍.北海市海滩互花米草分布面积为685.91 hm2,占入侵总面积的99.92%,钦州市海滩分布面积为0.57 hm2,占入侵总面积的0.08%.丹兜海互花米草入侵面积达317.89 hm2,但廉州湾斑块数量分布最多,为2777个.[结论]高分辨率卫星影像能有效地提取互花米草分布信息;广西互花米草正处于迅速扩张期,空间上自东往西扩散,最远已到达钦州市大风江口西部海域滩涂;廉州湾互花米草扩散正处于急速爆发期;自然保护区内红树林、海草床和土著盐沼植被等海洋生态系统已经受到互花米草的严重威胁,生态环境不容乐观.建议加强对互花米草扩散和防治机制的研究.%[Objective]The remote sensing monitoring of Spartina alterniflora was carried out in Guangxi intertidal zone,and the distribution of Spartina alterniflora was found out,which provided data support for scientific research and control of Spartina alterniflora in Guangxi.[Methods]Based on the high resolution satellite image of GF-1 in 2016,the current spread situa-tion of Spartina alterniflora was monitored and analyzed by the combination of remote sensing technology and field survey in Guangxi.[Results]As of July 2016,the intertidal area of Spartina alterniflora in Guangxi was 686.48 hm2 ,the number of patches was 5191,the aver-age patch area was 0.13 hm2 ,and the maximum patch area was 47.24 hm2 (it is located in the Dandouhai Sea area).The survey results showed that the area of Spartina alterniflora increased by 685.54 hm2 compared with the introduction period,and the area increased by 729 times.The distribution area of Spartina alterniflora was 685.91 hm2 in Beihai City,accounting for 99.92% of the total area of invasion,and the dis-tribution area in Qinzhou City was 0.57 hm2 ,ac-counting for 0.08% of the total area of invasion. The Dandouhai's area of Spartina alterniflora was 317.89 hm2 ,but the largest number of plaques was 2777 in Lianzhou Bay.[Conclusion]The distribution information of Spartina alterniflora can be effectively extracted by high reso-lution satellite images.The Spartina alterniflora in Guangxi is in a rapid expansion,which spreads in space from east to west.the farthest space has reached to the west of the Dafengjiangkou beach tidal flat in Qinzhou City.The spread of Spartina alterniflora is in a rap-id burst period in Lianzhou Bay.Marine ecosystems such as mangroves,seagrass beds and abo-riginal salt marsh in nature reserves have been seriously threatened by Spartina alterniflora , and the ecological environment is not optimistic.It is suggested to strengthen the research on the diffusion and control mechanism of Spartina alterniflora .