Determining the Impact of Nutrient, Organic Matter and Contaminant Fluxes From Melting Himalaya Glaciers on Downstream Ecosystems

确定喜马拉雅冰川融化产生的养分、有机物和污染物通量对下游生态系统的影响

• 批准号: 2137482
• 金额: --
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2018
• 资助国家: 英国
• 起止时间: 2018 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2137482
• 关键词: Determining; Impact; Nutrient; Organic; Matter

Around 75 % of the Earth's freshwater is locked up in mountain glaciers and ice sheets and is highly sensitive to changes in future climate. Glaciers located within the Hindu-Kush Himalayan region represent the largest store of freshwater held in mountain glaciers globally, and many are predicted to either retreat or disappear this century. The impacts of these changes upon the flow regimes major Asian rivers, which supply > 1.4 billion people, are becoming better studied. However, a major research gap is the impact of Himalayan glacier melting upon on the quality of water in these rivers, and thus on downstream ecosystem health. This is important for two main reasons. First, glacier runoff is often found to be enriched in nutrient and bioavailable organic matter, which may be important in sustaining downstream ecosystems and ecosystem services (e.g. fisheries). However, glacial catchments also sequester pollutants from the atmosphere in snowfall and release trace metals from bedrock via erosion, which are released to downstream aquatic ecosystems. While these impacts are well researched elsewhere (e.g. Alaska, European Alps, Greenland), the role of glacial meltwater in shaping the form and function of Himalayan aquatic ecosystems is a new field. It requires close cooperation with Himalayan host nations because of the remote nature of the field sites and requirement for governmental permission. This PhD project aims to employ novel in situ chemical sensing technologies developed via previous NERC funding (Discovery Grant "DELVE", Dr Liz Bagshaw, University of Cardiff and Dr Alex Beaton, National Oceanography Centre), in combination with chemical profiling of Himalayan glacier runoff for organic matter, inorganic nutrients (Profs. Jemma Wadham, Richard Evershed) and contaminants (Prof. Laura Robinson). It will be complemented by in situ biological measurements and bio-assays in the study river catchments to infer the bioavailability of exported nutrients/organic matter to planktonic communities and any incorporation of contaminants into biota (Prof. Alex Anesio). The project will be undertaken in collaboration with Prof. Al. Ramanathan at Jawaharlal Nehru University (JNU: New Delhi) who has developed several glacier field sites in the Indian Himalaya over the last 15 years. The project will specifically aim to determine the controls upon the fluxes of nutrient and organic matter (Objective 1) and of toxins (e.g. metals, micro plastics) (Objective 2) in runoff from Himalayan river catchments with contrasting glacial cover. It will go on to determine the impact of Himalayan river water quality upon downstream planktonic communities (Objective 3). This will result in a ground-breaking assessment of the impact of a deglaciating Himalaya upon downstream river water quality and aquatic ecosystems in warming world.

地球上大约 75% 的淡水被锁在山地冰川和冰原中，对未来气候的变化高度敏感。兴都库什-喜马拉雅地区的冰川是全球山地冰川中最大的淡水储量，预计许多冰川将在本世纪消退或消失。这些变化对供应超过 14 亿人口的亚洲主要河流水流的影响正在得到更好的研究。然而，一个主要的研究空白是喜马拉雅冰川融化对这些河流的水质以及下游生态系统健康的影响。这很重要，主要有两个原因。首先，冰川径流通常富含营养物和生物可利用的有机物，这对于维持下游生态系统和生态系统服务（例如渔业）可能很重要。然而，冰川集水区也会在降雪中隔离大气中的污染物，并通过侵蚀从基岩中释放微量金属，这些金属被释放到下游的水生生态系统中。虽然这些影响在其他地方（例如阿拉斯加、欧洲阿尔卑斯山、格陵兰岛）已得到充分研究，但冰川融水在塑造喜马拉雅水生生态系统的形式和功能中的作用是一个新领域。由于现场地点偏远且需要政府许可，因此需要与喜马拉雅东道国密切合作。该博士项目旨在采用先前 NERC 资助（发现补助金“DELVE”，卡迪夫大学 Liz Bagshaw 博士和国家海洋学中心 Alex Beaton 博士）开发的新型原位化学传感技术，并结合喜马拉雅冰川径流的化学分析有机物、无机营养物（Jemma Wadham 教授、Richard Evershed）和污染物（Laura Robinson 教授）。它将辅之以研究河流流域的原位生物测量和生物测定，以推断向浮游生物群落输出的营养物/有机物的生物利用度以及将污染物纳入生物群的情况（Alex Anesio 教授）。该项目将与 Al 教授合作进行。贾瓦哈拉尔尼赫鲁大学（JNU：新德里）的拉马纳坦在过去 15 年里在印度喜马拉雅山开发了多个冰川野外遗址。该项目的具体目标是确定对喜马拉雅河流域径流中养分和有机物（目标 1）和毒素（例如金属、微塑料）（目标 2）通量的控制，并与冰川覆盖形成对比。它将继续确定喜马拉雅河流水质对下游浮游生物群落的影响（目标 3）。这将对喜马拉雅山冰川消融对变暖世界中下游河流水质和水生生态系统的影响进行开创性评估。