中越北部湾红树林差异性研究

红树林是一种能够同时适应海洋和陆地的一种特殊植物种类,分布在约30°S~30°SN之间的热带、亚热带海岸和河口交界的潮间带上。红树林的分布除了受自然条件和气候的制约,还受一定程度的人为活动的干扰。本文选取了地貌、气候相似和经济发展不同的中国广西段和越南北部段的2个相邻海岸作为研究区,基于Landsat TM遥感影像,采用监督分类和人工解译的方法,获取了研究区1988、2000和2015年3个时期的红树林分布数据,并对比分析了2个岸段红树林时空转化、景观格局变化及驱动力的差异。研究表明：① 1988-2015年,中国广西段红树林面积呈增长趋势,2000年比1988年增长18%、2015年比2000年增长了75%;越南北部段先减少后增加,2000年红树林面积比1988年减少了20%,2015年比2000年增加了50%;② 红树林景观格局方面,中国广西段红树林平均斑块面积相对较小、破碎程度高,斑块形状较规则,趋近于正方形,受人为因素干扰程度较大,而越南北部段红树林斑块面积大、破碎化程度低,斑块呈带状或条状分布,受人为因素干扰的程度较小。 ③ 主要人为驱动因素方面,影响中国广西段红树林变化的主要人为驱动因素是变化的,1988-2000年以围垦建造养殖池为主,2000-2015年则以城镇用地和工矿建设为主,而越南北部段在1988-2015年一直以围垦养殖池为主。

Study on the Difference of Mangrove in Beibu Bay Between China and Vietnam

Mangrove is a special species which can adapt to the ocean and the land at the same time. Mangrove distributes in the coastal estuarine intertidal zone about 30°N~30°S on Earth where the climate is tropical or subtropical. The distribution of mangrove is restricted by the natural conditions and the climate. Also, it is disturbed by anthropogenic activities at a certain degree. Two adjacent regions, the coast of the Guangxi Zhuang Autonomous Region in China and the coast of Northern Vietnam, where the geomorphology and the climate are similar and the level of economic development is different, were chosen as the study area. Based on Landsat TM remote sensing images, we used the supervised classification and manual interpretation methods to acquire the distribution data of mangrove in the study areas in 1988, 2000 and 2015. We comparatively analyzed the differences in spatial-temporal transformation, the change of landscape pattern and the driving forces of the two coastal mangroves. This study indicated that: (1) During 1988-2015, the area of Guangxi Mangrove is increasing. It increased 18% in 2000 than that in 1988 and it increased 75% in 2015 than that in 2000. Northern Vietnam decreased first and then increased. In 2000, mangrove area decreased by 20% compared to that in 1988 and it increased by 50% in 2015 compared to that in 2000. (2) In the landscape pattern of mangrove, the average patch area of Guangxi Mangrove is relatively smaller, and it has higher degree of fragmentation, and the patch shape is more regular, closer to the square, more severely disturbed by human activities. North Vietnam mangrove has a larger patch area, lower degree of fragmentation, and the plaques have a shape of strips and were disturbed less severely by human activities. (3) The major human driving factors are as follows: the main human driving factors are changing in Guangxi Mangrove in China. From 1988 to 2000, cultivation ponds constructed by reclamation dominated. During 2000-2015, urbanization and factory-mining construction dominated. In North Vietnam, cultivation ponds constructed by reclamation always dominated during 1988-2015.