为全面摸清1960~2010年来广西红树林数量分布及其变化动态,采用航空图像、SPOT1-5、ALOS等中高分辨率遥感图像,提取1960~2010年5个时期(1960/1976年、1990s、2001年、2007年和2010年)广西红树林空间分布信息,研究其数量变化特征,结果表明:1960/1976年、1990s、2001年、2007年和2010年广西红树林面积分别为9 062.5、7 430.1、7 015.4、6 743.2、7 054.3 hm^2,斑块数量分别为1 020、829、1 094、1 718、1 712个,斑块平均面积分别为8.9、9.0、6.4、3.9、4.1 hm^2;1960~2010年红树林面积减少了22.16%,斑块数量增加了67.84%,斑块平均面积减少了53.93%;广西红树林呈现面积先持续减少后小幅增加、斑块数量先大幅减少后大幅增加并趋于稳定、斑块严重碎化后趋于稳定的趋势;各海湾不同时期的变化趋势相差较大;养殖塘和盐田建设、围垦、城市扩张与工程建设、人工造林是导致红树林面积和斑块数量变化的主要原因。
In order to quantify the mangrove distribution and dynamics in Guangxi from 1960 to 2010, medium and high resolution remote-sensing images such as aerial image,SPOT1- 5 and ALOS were used to extract spatial information of mangrove in 1960 /1976,1990s,2001,2007 and 2010. Subsequently, the quantity dynamics of mangrove was analyzed in Guangxi. The results indicated that there were 9 062. 5 hm2,7 430. 1 hm2,7 015. 4 hm2,6 743. 2 hm2,7 054. 3 hm2mangrove and 1 020,829, 1 094,1 718,1 712 mangrove patches in 1960 /1976,1990s,2001,2007 and 2010 respectively. At the same time,the average area of mangrove patches were 8. 9 hm2,9. 0 hm2,6. 4 hm^2,3. 9 hm^2and 4. 1 hm^2in these years respectively. From 1960 to 2010,Guangxi lost 22. 16% mangrove and the average area of mangrove patches decreased 53. 93% while the patch-number increased 67. 84%. Mangrove in Guangxi showed the trend that the area increased slightly after continued decline. The patch numbers decreased slightly then increased significantly and stabilized,and the patches fragmented significantly then stabilized. Mangrove dynamics trend in different gulfs showed significant difference in different periods. Marineculture and saltern,city development and construction,inning and plantation were the major change drivers of mangrove.