摘要
Agricultural, urban and industrial activities have dramatically increased aquatic nitrogen and phosphorus pollution (eutrophication), threatening water quality and biotic integrity from headwater streams to coastal areas world‐wide. Eutrophication creates multiple problems, including hypoxic “dead zones” that reduce fish and shellfish production; harmful algal blooms that create taste and odor problems and threaten the safety of drinking water and aquatic food supplies; stimulation of greenhouse gas releases; and degradation of cultural and social values of these waters. Conservative estimates of annual costs of eutrophication have indicated $1 billion losses for European coastal waters and $2.4 billion for lakes and streams in the United States. Scientists have debated whether phosphorus, nitrogen, or both need to be reduced to control eutrophication along the freshwater to marine continuum, but many management agencies worldwide are increasingly opting for dual control. The unidirectional flow of water and nutrients through streams, rivers, lakes, estuaries and ultimately coastal oceans adds additional complexity, as each of these ecosystems may be limited by different factors. Consequently, the reduction of just one nutrient upstream to control eutrophication can allow the export of other nutrients downstream where they may stimulate algal production. The technology exists for controlling eutrophication, but many challenges remain for understanding and managing this global environmental problem.
摘要译文
农业，城市和工业活动极大地增加了水体氮和磷的污染（富营养化），从上游水源到全世界沿海地区，都威胁着水质和生物完整性。富营养化产生了许多问题，包括低氧的“死区”，这些鱼类减少了鱼类和贝类的生产；有害的藻华会产生味道和气味问题，并威胁饮用水和水生食品的安全；刺激温室气体排放；以及这些水域的文化和社会价值的下降。保守估计每年的富营养化成本表明，欧洲沿海水域损失了10亿美元，美国湖泊和溪流损失了24亿美元。科学家们一直在争论是否需要减少磷，氮或两者的含量，以控制淡水至海洋连续体的富营养化，但是全世界许多管理机构越来越多地选择双重控制。水和营养物通过溪流，河流，湖泊，河口以及最终沿海海洋的单向流动增加了额外的复杂性，因为这些生态系统中的每一个都可能受到不同因素的限制。因此，减少上游一种营养素以控制富营养化可以使其他营养素向下游输出，从而刺激藻类生产。存在用于控制富营养化的技术，但是在理解和管理这一全球环境问题方面仍然存在许多挑战。
Wayne A. Wurtsbaugh[1];Hans W. Paerl[2];Walter K. Dodds[3]. Nutrients, eutrophication and harmful algal blooms along the freshwater to marine continuum[J]. Wiley Interdisciplinary Reviews: Water, 2019,6(5)