Effects of Human Impact on the Wetland Ecosystem

人类影响对湿地生态系统的影响

基本信息

批准号：
02306002
负责人：
ARUGA Yusho
金额：
--
依托单位：
Tokyo University of Fisheries
依托单位国家：
日本
项目类别：
Grant-in-Aid for Co-operative Research (A)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1992
项目状态：
已结题

项目摘要

(1) Vegetation distribution maps were prepared around the middle course of River Tamagawa. It was shown that man's influence caused simplification of the floristic composition of plant community and reduced the number of plant communities. The input of COD, N and P into Tokyo Bay in 1989 was estimated to be 300,320 and 26 tons/day, respectively, only 3.8% of which were contributed from River Tamagawa. Denitrification activity at tidal flat of the River Tamagawa estuary was estimated to be 178 mumol/m^2/h in December 1991. LAS were removed completely in summer and about 80% in winter mainly by microbial activities in the River Tamagawa estuary. Organic carbon production and organic nitrogen production by phytoplankton off the River Tamagawa estuary in Tokyo Bay Were estimated to be 1,880 gC/m^2/yr and 281 gN/m^2/yr,respectively. (2) Distributions of the Phragmites community and standing stock and species composition of algae attached to Phragmites were investigated in Lake Kasumigaura. … More In most part of the lake, Phragmites community has been heavily affected and destroyed by shore-protection works. It was found that variations of nitrate and nitrite concentrations in lake water were big in the Phragmites zone but small in the Nymphoides zone, and variations of nitrous oxide concentration in the littoral zone seemed to be coupled with those of nitrate and nitrite concentrations. (3) A study was carried out to clarify the interaction between sulfate reduction and methane formation in brackish water wetland and to identify the sources and mechanisms responsible for the emission of methane into atmosphere. The results showed that the predominance of sulfate reducing reaction may suppress methane formation in brackish water wetland. Lake sediments of Songkhla Lake were surveyed and examined for their possible use to land restoration. It was clarified that the efficient desalinization of heavy clayey deposits is needed, and after desalinization they are dried and can be applied for land as soil dressing materials in degraded areas. Less

(1) 绘制了玉川河中游附近的植被分布图。结果表明，人类的影响导致植物群落组成的简化，减少了东京湾的COD、N和P的输入。 1989 年估计分别为 300,320 吨/天和 26 吨/天，其中只有 3.8% 来自玉川河滩涂的反硝化活动。 1991年12月，玉川河口估计为178 mumol/m^2/h。LAS在夏季被完全去除，冬季约80%，主要是通过玉川河口微生物活动产生的有机碳和浮游植物产生的有机氮。东京湾玉川河口附近估计为 1,880 gC/m^2/yr 和 281 gC/m^2/yr gN/m^2/yr,分别。 (2) 霞浦湖芦苇群落分布及芦苇附着藻类的存量和物种组成。湖区大部分地区芦苇群落受到严重影响。发现芦苇区湖水中硝酸盐和亚硝酸盐浓度变化较大，荇菜区湖水中硝酸盐和亚硝酸盐浓度变化较小。沿海地区一氧化二氮浓度似乎与硝酸盐和亚硝酸盐浓度相关（3）进行了一项研究，以阐明咸水湿地中硫酸盐还原和甲烷形成之间的相互作用，并确定其来源和机制。研究结果表明，硫酸盐还原反应的主导作用可能会抑制宋卡湖微咸水湖沉积物中甲烷的形成。研究表明，需要对重粘土沉积物进行有效脱盐，脱盐后可将其干燥并可用作退化地区的土壤修复材料。