Environmental Systems Analysis Group, Wageningen University and Research, P.O. Box 47, 6700 AA, Wageningen, the Netherlands.
Environmental Systems Analysis Group, Wageningen University and Research, P.O. Box 47, 6700 AA, Wageningen, the Netherlands.
Sci Total Environ. 2019 Feb 10;650(Pt 2):1935-1943. doi: 10.1016/j.scitotenv.2018.09.347. Epub 2018 Sep 28.
Microbial pollution is a major problem worldwide. High concentrations of Escherichia coli have been found in Kabul River in Pakistan. E. coli concentrations vary under different socio-economic conditions, such as population and livestock densities, urbanisation, sanitation and treatment of wastewater and manure, and climate-change aspects, such as floods and droughts. In this paper, we assess potential future E. coli loads and concentrations in the Kabul River using the Soil and Water Assessment Tool with scenarios that are based on the most recent Shared Socio-economic Pathways and Representative Concentration Pathways (SSPs and RCPs) developed for the Intergovernmental Panel on Climate Change (IPCC). Scenario_1 considers moderate population and livestock density growth, planned urbanisation and strongly improved wastewater and manure treatment (based on SSP1, "Sustainability"), and moderate climate change (RCP4.5, moderate greenhouse gas (GHG) emissions). Scenario_2 considers strong population and livestock density growth, moderate urbanisation, slightly improved wastewater treatment, no manure treatment (based on SSP3, "Regional rivalry") and strong climate change (RCP8.5, high GHG emissions). Simulated E. coli responses to Scenario_2 suggest a mid-century increase in loads by 111% and a late century increase of 201% compared to baseline loads. Similarly, simulated E. coli loads are reduced by 60% for the mid-century and 78% for the late century compared to the baseline loads. When additional treatment is simulated in Scenario_1, the loads are reduced even further by 94%, 92% and 99.3% compared to the baseline concentrations when additional tertiary treatment, manure treatment or both have been applied respectively. This study is one of the first to apply combined socio-economic development and climate change scenario analysis with an E. coli concentration model to better understand how these concentrations may change in the future. The scenario analysis shows that reducing E. coli concentrations in Pakistan's rivers is possible, but requires strongly improved waste water treatment and manure management measures.
微生物污染是一个全球性的主要问题。在巴基斯坦的喀布尔河发现了高浓度的大肠杆菌。大肠杆菌的浓度因人口和牲畜密度、城市化、废水和粪便的处理以及洪水和干旱等气候变化方面等不同的社会经济条件而有所不同。在本文中，我们使用土壤和水评估工具 (Soil and Water Assessment Tool)，根据政府间气候变化专门委员会 (Intergovernmental Panel on Climate Change，简称 IPCC) 开发的最新共享社会经济路径 (Shared Socio-economic Pathways，简称 SSPs) 和代表性浓度路径 (Representative Concentration Pathways，简称 RCPs)，评估了喀布尔河未来潜在的大肠杆菌负荷和浓度。情景 1 考虑了人口和牲畜密度的适度增长、计划中的城市化以及废水和粪便处理的大力改善（基于 SSP1，“可持续性”），以及适度的气候变化（RCP4.5，中度温室气体排放）。情景 2 考虑了人口和牲畜密度的强劲增长、适度的城市化、略有改善的废水处理、没有粪便处理（基于 SSP3，“区域竞争”）以及强烈的气候变化（RCP8.5，高温室气体排放）。与基线负荷相比，情景 2 模拟的大肠杆菌对情景 2 的反应表明，到本世纪中叶负荷增加 111%，到本世纪末负荷增加 201%。同样，与基线负荷相比，到本世纪中叶和本世纪末，模拟的大肠杆菌负荷分别减少了 60%和 78%。当在情景 1 中模拟额外的处理时，与基线浓度相比，当分别应用额外的三级处理、粪便处理或两者都应用时，负荷分别减少了 94%、92%和 99.3%。本研究是首次将社会经济发展和气候变化情景分析与大肠杆菌浓度模型相结合，以更好地了解未来这些浓度可能如何变化。情景分析表明，在巴基斯坦的河流中减少大肠杆菌浓度是可能的，但需要大力改善废水处理和粪便管理措施。
