Abstract The increase of freshwater inflow to Kalametiya lagoon, Sri Lanka, as a result of Udawalawe irrigation project that came into operation in 1967, has caused heavy siltation and reduction of salinity in the lagoon. The present investigation attempted to study and convey the current situation of Kalametiya lagoon and its future trajectory in response to unremitting disturbances. About 86% of the water surface area has been sacrificed to Sonneratia caseolaris and Typha angustifolia as dominant riparian vegetation and the water quality of the remaining water body has also deteriorated as evident by increased acidity, reduced dissolved oxygen and increased ammonium content. If the present trend continues, chances of losing the remaining water surface area in 2-3 years are predictably high. These spatio-temporal changes apparently diminished the uses and services of the coastal lagoon. Improper planning and lack of institutional coordination have caused such a menace. As many coastal lagoons worldwide experience similar degradation due to ill-planned development projects, careful considerations should be given to long-term impact assessment of a development project before implementation. This case-study can, therefore, be taken as a lesson in coastal zone management in other parts of the world.

中文翻译：

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内陆灌溉工程导致沿海泻湖消失：1956年至2016年斯里兰卡卡拉梅蒂亚泻湖的轨迹

摘要 斯里兰卡卡拉梅蒂亚泻湖的淡水流入量增加，这是由于 1967 年投入运行的 Udawalawe 灌溉项目造成的，造成泻湖严重淤积和盐度降低。本次调查试图研究和传达卡拉梅蒂亚泻湖的现状及其在不断扰动下的未来轨迹。大约 86% 的水表面积已被作为主要河岸植被的干酪海桑和香蒲牺牲，其余水体的水质也因酸度增加、溶解氧减少和铵含量增加而恶化。如果目前的趋势继续下去，预计在 2-3 年内失去剩余水表面积的可能性很高。这些时空变化显然减少了沿海泻湖的用途和服务。规划不当和缺乏机构协调造成了这种威胁。由于世界各地的许多沿海泻湖由于规划不当的开发项目而经历了类似的退化，因此在实施之前应仔细考虑开发项目的长期影响评估。因此，本案例研究可以作为世界其他地区沿海地区管理的一课。在实施之前，应仔细考虑发展项目的长期影响评估。因此，本案例研究可以作为世界其他地区沿海地区管理的一课。在实施之前，应仔细考虑发展项目的长期影响评估。因此，本案例研究可以作为世界其他地区沿海地区管理的一课。