CONSERVATION OF TROPICAL SEAGRASS BEDS WITH SPECIAL REFERENCE TO THEIR ROLE ON FUNCTION OF COASTAL ECOSYSTEM

热带海草床的保护，特别是其对沿海生态系统功能的作用

基本信息

批准号：
12575032
负责人：
KOIKE Isao
金额：
$ 9.34万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2002
项目状态：
已结题

项目摘要

Field studies were conducted under the title "Conservation of tropical seagrass beds with special reference to their role on function of coastal ecosystem" to quantify the stress of terrestrial nutrients, sediment materials and human changes of coastal line on seagrass ecosystem including benthic populations facing to the Andaman Sea side of Thailand. Followings are major research outcomes of this project.1) We analyzed how the dominated species of seagrass adapts to external environmental change such as sediment supply and decrease of light intensity. And we indicated the importance of morphological adaptation of seagrasses including the fine roots of vertical rhizomes, as well as adjustment of photosynthetic products distribution among upper and below bottom.2) Stable isotope ratios of nitrogen, carbon and sulfur within the various parts of seagrasses could be used as a good indicator of small scale environmental stress. on seagrass metabolisms3) Comparison of species diversity and biomass distributing different environmental setting, from the location of big river mouth to that of no river inflow influence, indicated that both biomass and species diversity of seagrass decreased with the increase of river influences at least in this study area.4) Based on the field observations of physical forcing causing re-suspension of seagrass sediments, we identified three factors, i.e., tidal current, wind induced re-suspension and inflow or terrestrial solids. Even within the rather narrow area of seagrass beds, spatial and temporal variation of these three factors were observed, also effecting on metabolisms of benthic organisms associated with seagrass beds,5) Food preference of dugong for different types of seagrass species was examined and importance of Halophila beds for the diet of dugong of this area.

进行现场研究的标题是“保存热带海草床，特别提及了它们在沿海生态系统功能上的作用”，以量化陆地养分，沉积物材料和人类在海草生态系统上的压力，包括面对底栖生物的底栖人群，属于Thailand的Andaman Sea Side。以下是该项目的主要研究结果。1）我们分析了主导的海草物种如何适应外部环境变化，例如沉积物供应和光强度的降低。我们指出了海草形态适应的重要性，包括垂直根茎的细根，以及对底部下方和下方的光合产物分布的调整。关于海草代谢3）比较物种多样性和生物量分布不同的环境环境的比较，从大河口的位置，无河流流入影响的位置，表明，基于该研究区域的河流的增加，海草的生物量和物种多样性都会随着河流的增加而降低。电流，风引起的重悬于和流入或陆地固体。即使在海草床的相当狭窄区域内，也观察到了这三个因素的空间和时间变化，也影响了与海草床相关的底栖生物的新陈代谢，5）检查了丘陵对不同类型的海草物种的食物偏好，并且对卤素床的重要性却是该区域dugong饮食的重要性。