Are nutrients retained by river damming?

• 作者: Jack J.Middelburg
• 来源期刊: 国家科学评论（英文版）
• 年，卷（期）: 2020,（9）
• 所属期刊栏目: COMMENTARIES
• 页码范围: 1458
• 页数: 1页
• 语种: 英文
• DOI: 10.1093/nsr/nwaa073

摘要

Rivers are dammed for hydropower, flood control, navigation or water storage for human use.Globally, about half of the rivers are impacted by damming [1], with major consequences for biodiversity, fish migration, primary production, greenhouse gas emissions and retention of nutrients [2,3]. The traditional view is that dam closure leads to an increase in water residence time, settling of suspended particles and improved light conditions.This amplifies primary productivity and thus the stripping of dissolved nutrients from the water while transiting [2].The imported and locally produced organic matter serles to the sediment, where part of it is mineralized to carbon dioxide, methane, phosphate and ammonium, and another part is temporarily or permanently buried.This nutrient transfer from transiting river water to the sediment causes removal of nutrients via burial and dinitrogen gas production by denitrification and Anammox.This retention from dam construction reduces nutrient supply to downstream ecosystems and thus partly alleviates eutrophication.