运用景观生态学的理论与方法,结合2005、2008、2012和2015年4个时段Quick Bird图像,定量研究广西廉州湾红树林湿地景观格局的特征.2005—2015年,该区域红树林面积年平均增长率为8.44%,其中自然生长占增加面积的96.69%;人工造林占增加面积的3.31%.2005—2015年,减少的红树林面积为104216 m2,为挖塘养殖、修建堤坝、挖河道、河水冲击、鱼藤、团水虱等自然因素和人为干扰构成,其中自然因素占63.79%,人为干扰占36.21%.截止2015年,互花米草面积51.1706 hm2,其中2005—2012年平均增长率为55.05%, 2012—2015年平均增长率为59.17%;因鱼藤缠绕覆盖造成的红树林死亡面积最大,约33616 m2.2005—2012年红树林因团水虱危害死亡面积7990 m2;截止2015年10月,无瓣海桑分散扩散的单体植株为670株,最远扩散距离达6408 m.2005—2012年景观格局指数呈现下降趋势,景观破碎化降低;2012年后景观格局指数趋于上升,景观异质增强.稳定期红树林斑块平均分维数为1.0539,平均形状系数为1.4892.红树林湿地的保护和恢复要尽量利用本土物种的自然生长扩散来达成,人工造林的红树林斑块块形状可以参考天然红树林斑块形状.红树林损失的主要原因已由人为直接干扰转变为自然干扰,该区域红树林湿地面临的主要生态问题有无瓣海桑扩散、鱼藤蔓延、互花米草入侵和团水虱危害.%Using the theory and method of landscape ecology, the research focused on the dynamic change characteristics of mangrove wetland landscape pattern in Lianzhou gulf,Guangxi quantitatively with Quick Bird images in 2005,2008,2012,2015. The results proved that:between 2015 and 2005,the area of mangrove with an average annual growth rate of 8.44% while natural growth took account for 96.69% and plantation took account for 3.31% of the area. From 2005 to 2015, there were 104 216 m2 mangrove land which were occupied by natural and manual disturbance such as digging pond for farming, building dams, dredging river,river impacting, Derris trifoliata, Sphaeromidae. Natural factors accounted for 63.79% while human impacts accounted for 36.21%. Among them,Spartina alterniflora area was 51.170 6 hm2in 2015 with an annual growth rate of 55.05% from 2005 to 2012 and 59.17% from 2012 to 2015. The largest mangrove forest death area was due to D. trifoliata with the mangrove forest death area of 33 616 m2. From 2005 to 2012, 7 990 m2mangrove forest death area were caused by Sphaeromidae. To October, 2015, 670 single survival Sonneratia apetala plants were spread and the most distant distance was 6 408 m. The landscape pattern indexes of mangrove forest in Lianzhou gulf showed a decreasing trend from 2005 to 2012 and the landscape fragmentation has reduced. The landscape pattern indexes turned to a upward trend suggesting the landscape heterogeneity has enhanced since 2015. The average fractal dimension of the stable mangrove plaque was 1.053 9 and the average shape coefficient was 1.489 2. The natural growth and spread of native species should be mostly used for the protection and restoration of mangrove wetlands. Artificial afforestation of the mangrove patch shape can refer to the natural mangrove patch shape. The main reason for the loss of mangrove forests has changed from the direct man-made disturbance to natural disturbance. The main ecological problems of mangrove wetlands are as followings:the diffusion of Sonneratia apetala and D. trifoliata,invasion of Spartina alterniflora and disadvantage of Sphaeromidae.
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