广西红树林的数量分布

Quantitative distribution of mangroves in Guangxi Zhuang Autonomous Region

为摸清广西红树林的数量分布 ,采用遥感、GIS和GPS技术与地面调查相结合的方法对广西红树林进行了全面的调查 .在此基础上以自然海湾为研究单位 ,对广西红树林的空间分布、群落类型和覆盖度、树高等级等林分结构进行了分析评价 .结果表明 ,红树林在宏观上沿整个海岸线呈展开式均匀分布 ,在 14 89 64km海岸线中 ,间断距离 <2km的红树林岸段占海岸线总长度的 75 7% ;14个海湾中有 10个海湾的红树林岸线率≥ 80 % ;红树林分布由海岸 (堤 )向外海延伸 50～ 10 0 0m ,最远外延达 2 82 0m ;74 4%的红树林分布于海堤外侧 ;桐花树群落 (Comm .Ae gicerascorniculatum)、白骨壤群落 (Comm .Avicenniamarina)、秋茄—桐花树群落 (Comm .Kandeliacandel,Aegicerascornic ulatum)和白骨壤 +桐花树群落 (Comm .Avicenniamarina ,Aegicerascorniculatum )为优势群落 ;61 9%的红树林覆盖度≥70 % ;78 1%的红树林平均高度 <2

In order to find out the quantitative distribution of mangroves in Guangxi Zhuan g Autonomous Region, an inventory for mangroves along the coast of Guangxi, west ern Beibu Gulf was carried out with the method of remote sensing, geographic information system, global positioning system together with field investigation in 2001.Then the space distribution, community typ e, crown d ensity and forest stand structure of mangroves with natural gulf as research uni t in Guangxi were analyzed and evaluated. The result indicates that the m angroves' distribution is uniform from the macro view. The mangrove coasts w ith the gap length in mangrove distribution less than 2 km account for 75.7% of total 1 489 64 km coastline and there are ten out of total fourteen gulfs, whe re m angrove coast proportion is more than 80%. Mangrove distribution extends 50～1 0 00 m from the coast or dyke to open waters, the farthest part reaches 2 820 m. 7 4 4% of mangroves are located outside the sea_dike,Comm. Aegiceras corniculatu m,Comm.Avicennia marina,Comm.Kandelia candel, Aegiceras corn iculatum and Comm.Avicennia marina+ Aegiceras corniculatum are the dominant communities, the crown density of 61 9% of mangroves is highe r than 70%, and the average height of 78 1% of mangroves is lower than 2 0 m.