Department of Water Management, Delft University of Technology, Stevinweg 1, 2628CN, Delft, The Netherlands.
Sci Rep. 2017 Feb 23;7:43289. doi: 10.1038/srep43289.
Organic pollution of rivers by wastewater discharge from human activities negatively impacts people and ecosystems. Without treatment, pollution control relies on a combination of natural degradation and dilution by natural runoff to reduce downstream effects. We quantify here for the first time the global sanitation crisis through its impact on organic river pollution from the threats of (1) increasing wastewater discharge due to urbanization and intensification of livestock farming, and (2) reductions in river dilution capacity due to climate change and water extractions. Using in-stream Biochemical Oxygen Demand (BOD) as an overall indicator of organic river pollution, we calculate historical (2000) and future (2050) BOD concentrations in global river networks. Despite significant self-cleaning capacities of rivers, the number of people affected by organic pollution (BOD >5 mg/l) is projected to increase from 1.1 billion in 2000 to 2.5 billion in 2050. With developing countries disproportionately affected, our results point to a growing need for affordable wastewater solutions.
人类活动排放的废水导致河流受到有机污染，对人类和生态系统造成负面影响。未经处理，污染控制依赖于自然降解和自然径流量稀释的结合，以减少下游影响。我们首次通过量化（1）城市化和畜牧业集约化导致的废水排放量增加，以及（2）气候变化和水资源抽取导致的河流稀释能力下降这两个因素对有机河流污染的威胁，来量化全球卫生危机。我们使用河流中生化需氧量（BOD）作为有机河流污染的综合指标，计算全球河网中 2000 年的历史 BOD 浓度和 2050 年的未来 BOD 浓度。尽管河流具有很强的自净能力，但受到有机污染（BOD＞5mg/L）影响的人数预计将从 2000 年的 11 亿增加到 2050 年的 25 亿。发展中国家受到的影响不成比例，我们的研究结果表明，需要更多负担得起的废水解决方案。
