LTLS Freshwater Ecosystems ("LTLS-FE"): Analysis and future scenarios of Long-Term and Large-Scale freshwater quality and impacts

长期大规模淡水生态系统(LTLS-FE)：英国淡水在历史上和目前都受到许多化学压力，影响其质量和随之而来的生物条件。虽然一些压力(如金属、酸化、耗氧物质)近几十年来似乎有所减轻，但其他压力(如工业和个人有机微污染物、氮和磷)仍然存在，而且可能还在增加。英国淡水质量和生物多样性的这种当代改善是否会持续到未来，对于依赖淡水娱乐的公众、饮用水供应的自来水公司、行业和法定监管机构来说都是非常感兴趣的-最近的证据表明，生物多样性最近的一些改善可能已经停滞不前。预测未来气候对英国淡水数量的影响最近已被量化，但很少有研究全面探讨气候变暖和流域变化可能如何影响英国淡水质量过程、污染物相互作用和生物多样性。探索英国规模的水质未来可能会发生什么变化，需要了解其众多的、空间上可变的驱动因素，以及它们如何随着时间的推移相互作用，以及一个可以将所有这些信息整合在一起的模型。在这个名为“长期大型淡水生态系统”或“LTLS-FE”的项目中，我们的目标是使用英国景观的动态模型来模拟从现在到未来我们淡水的健康和质量。然而，未来是高度不确定的，所以我们不得不考虑一些可能性，或者说“情景”。这些情景将被用作我们的模型(LTLS-淡水模型)的输入，并将使我们能够量化河流和湖泊对预测的未来气候和相关的污染化学品和病原体(统称为“污染物”)情景的响应以及它们对淡水生物多样性的可能影响。为了将国家规模的水质模型与淡水生物多样性模型联系起来，我们将首先使用现有的英国硅藻、大型植物、大型无脊椎动物和鱼类的淡水数据，以了解河流生态系统如何受到营养、水文、形态、温度和毒素等多种压力因素的影响。使用统计模型的第二种方法将使我们能够调查生态特征在多大程度上解释了应激源反应。模型将被用来外推到2080年之前空间和不同情景下的生态响应。到2080年的多个情景的水文和生态模拟将产生未来英国每条河流(在5公里网格上)的污染物和生态响应情景。将与利益相关者和项目团队讨论这些场景，以确定呈现它们的最佳方式。备选方案包括分析特定区域或河流如何缓解淡水风险，和/或分析以帮助确定众多变化中的哪一个或每个集水区的变化组合对下游淡水质量和生物群的影响最大。为了最大限度地利用项目的产出，我们将与利益相关者接触，以更好地了解对他们有广泛用途的模型和数据集。此后，项目中开发的所有模型代码都将是开源的，并可在公共储存库(GitHub)中获得，数据集将在可公开获得的NERC环境信息数据中心(EIDC)中获得。对于那些可能不希望下载模型代码和数据集的利益攸关方，将以基于地图的网络工具的形式提供更直观的替代方案，以显示英国河流的水质和生物多样性在未来几十年可能发生的变化。

Long Term Large Scale - Freshwater Ecosystems (LTLS-FE):UK freshwaters have historically and are currently subject to many chemical pressures on their quality and consequent biological condition. While some pressures (e.g. metals, acidification, oxygen-consuming substances) appear to have eased over recent decades, others (e.g. industrial and personal organic micropollutants, nitrogen and phosphorus) remain and may be increasing. Whether these contemporary improvements in UK freshwater quality and biodiversity will continue into the future is of great interest to the public who rely on freshwaters for recreation, to water companies for drinking water supply, to industry and to the statutory regulators - and there is recent evidence that some recent improvements to biodiversity may have stalled. The impact of projected future climate on UK freshwater quantity has been recently quantified, but few studies have comprehensively explored how UK freshwater quality processes, pollutant interactions and biodiversity, might be impacted by a warmer climate and catchment changes. Exploring how water quality at the UK scale may change in the future requires an understanding of its numerous, spatially variable drivers and how they interact over time, and a model that can put all this information together. In this project, called "Long Term Large Scale - Freshwater Ecosystems" or "LTLS-FE", our objective is to use a dynamic model of the UK landscape to simulate the health and quality of our freshwaters from the present day into the future. However, the future is highly uncertain, so we have to consider a number of possibilities, or "scenarios". These scenarios will be used as input to our model (LTLS-Freshwater Model) and will allow us to quantify the responses of rivers and lakes to projected future climates and associated scenarios of polluting chemicals and pathogens (collectively referred to as "pollutants") and their likely impacts on freshwater biodiversity.To link the national-scale water quality model with a freshwater biodiversity model we will first use available UK freshwater data for diatoms, macrophytes, macroinvertebrates and fish to develop an understanding of how riverine ecosystems are affected by multiple stressors such as nutrients, hydrology, morphology, temperature and toxins. A second approach using statistical models will allow us to investigate the extent to which ecological traits account for stressor responses. Models will be used to extrapolate ecological responses to stressors in space and under the different scenarios up to 2080.The hydrological and ecological modelling of multiple scenarios up to 2080 will result in future scenarios of pollutants and ecological responses for every UK river (on a 5km grid) across the UK. These scenarios will be discussed with stakeholders and the project team to identify the best way to present them. Options include analyses showing how particular regions or rivers can mitigate against freshwater risks, and/or analyses to help identify which of the many changes, or combination of changes in each catchment has the greatest impact on downstream freshwater quality and biota. To maximise the uptake of the outputs from the project we will engage with stakeholders to better understand the models and datasets that are of extended use to them. Following on from this, all model code developed in the project will be open source and available in a public repository (github), and datasets will be made available in the publicly available NERC Environmental Information Data Centre (EIDC). For those stakeholders who may not wish to download model code and datasets, a more-visual alternative will be provided in the form of a map-based web-tool to show how water quality and biodiversity in UK rivers might change in the coming decades.