天目湖水环境与渔业生产及旅游发展的关系

根据2001年6月～2002年5月在天日湖进行的每月一次的全湖周年观测以及相关的历史资料，全面分析了天日湖水环境的演变趋势，发现天日湖水质下降极为明显，并且随着渔业生产和游客的逐年增加，呈现出加速恶化的趋势，水质恶化主要表现为蓝藻、绿藻迅速繁殖，感官质量下降。分析原因，主要是由于上游围湖养鱼、湖内放养及附近宾馆饭店捧放出大量氮磷营养盐所致。针对当前天日湖水环境现状，提出了保护水源、改善水质的对策措施：(1)严格控制污染源：(2)退渔还湖，恢复水生植被；(3)调整养殖结构：(4)恢复植被，控制面源氮磷入湖量；(5)加强流域管理，确定水源保护地；(6)实施生态旅游。

Relation of water environment of Tianmuhu Lake and fishery and tourism

Based on the in site investigation data obtained during the period from June 2001 to May 2002 and the history data from Liyang Environmental Protection Bureau in Tianmuhu Lake, the evolution trend of water environment is analyzed in detail. The results show that water quality decreases significantly and continuously aggravates with fishery and increase of tourists. The main water environment problem is water quality in Tianmuhu Lake has evidently been deteriorated. The symptom of the water deterioration can be seen from the fact that blue-green, and green algae quickly reproduce and sight quality decreases. Having done some field monitoring and over analysis of the trend of water environment in Tianmuhu Lake, we found that the main causes are: the increases of aquiculture and accommodating facilities in resort. Aiming to the present situation of water environment, the countermeasures of protecting water reserve and ameliorating water quality are given: (1) Strictly controlling the sources of pollution; (2) Restoring macrophyte; (3) Adjusting framework of aquiculture; (4) Restoring vegetation and controlling the input of nitrogen and phosphorus; (5) Intensifying the management of valley; (6) Enforcing ecological tourism.