The Multi-Scale Response of Water Quality, Biodiversity and C Sequestration to Coupled Macronutrient Cycling from Source to Sea

传统上，流域研究集中在水流和水质的科学和管理上。近年来，实现良好的生态状况和遵守水框架指令一直是优先事项。这一直是具有挑战性的，尤其是因为英国的大多数河流都受到氮，磷和一系列污染物的严重污染，包括病原体和来自高地地区的溶解有机碳的转移正在增加。这些可能对河流和沿海沃茨的生态有害，对人类健康构成风险，并增加水工业的成本。在《国家生态系统评估》（2011年）和政府《自然环境白色文件》（2011年）发布后，集水区管理者面临着更大的挑战，他们试图确保水资源目标不会损害其他功能的提供，这些功能提供了一系列我们都受益的调节、供应或文化服务。提供这些生态系统服务的基础是基本的生态系统过程，如植物固碳和碳通过分解返回大气（碳循环），氮和磷等营养物质在植物、土壤、水和大气中的循环，以及包括病原体在内的一系列污染物的解毒。关于碳、氮和磷（C、N和P）和污染物的循环，人们已经知道很多，但是，很少研究这些循环通过景观的耦合以及随后对自然环境和所提供服务的影响。为了回应我们目前理解的这一差距，我们将解决两个研究问题。第一个是什么时候，在哪里，以及如何耦合宏量营养元素循环（C，N和P）影响自然环境的功能和景观单元之间的流域尺度？第二个问题是，在土地利用、空气污染和气候变化下，这些耦合循环将如何改变，以及在流域和国家尺度上对水质、碳固存和生物多样性（三个重要的生态系统服务）将产生什么影响？为了实现这一目标，我们将通过关键过程（净初级生产力，分解，营养循环）量化C，N和P循环的通量，转换和耦合，并使用有针对性的现场监测和现场和实验室为基础的实验相结合，在康威集水区补充在Ribble的集约化养殖区的测量，量化病原体转移和生存能力的联系。预计取得以下成果：1。量化和改善过程的理解耦合C，N和P的过程，转换和通量跨土壤功能类型和加工热点。2.定量分析了非稳态生态系统功能和N/P共同限制对淡水富营养化发展的影响.检验陆地和淡水生物多样性可以在流域和国家尺度上解释为常量营养素通量和初级生产力函数的假设。从源到海通量的量化和过程--了解病原体的命运和微细沉积物（絮凝物）中大量营养素的控制。5.一个综合的、简约的耦合常量营养素（C、N、P）气-陆-水建模平台，配置为横跨康威的1公里网格（即增强的JULES模型）。碳固存、水质和生物多样性对过去和未来气候、养分和土地（森林）覆盖变化的敏感性分析，以确定对过去和未来碳固存、水质和生物多样性变化的关键控制。量化在集水范围内提供固碳、水质和生物多样性方面的权衡以及与土地覆盖类型和气候状况的关系。

Catchment research has traditionally been focussed on the science and management of water flow and quality. In recent years, achieving good ecological status and compliance with the Water Framework Directive has been a priority. This has been challenging not least because the majority of rivers in the UK are heavily polluted with nitrogen, phosphorus, and a range of contaminants including pathogens and transfers of dissolved organic C from upland areas are increasing. These can be detrimental to the ecology of rivers and coastal waters, be a risk for human health and increases costs of the water industry. Following the publication of the National Ecosystem Assessment (2011) and the Government's White Paper on the Natural Environment (2011), catchment managers face an even greater challenge trying to ensure water resource objectives do not compromise delivery of other functions which deliver a range of regulating, provisioning or cultural services which we all benefit from. Underpinning delivery of these ecosystem services are basic ecosystem processes such as carbon fixation by plants and the return of carbon back to the atmosphere through decomposition (the carbon cycle), the cycling of nutrients such as nitrogen and phosphorus through plants, soil, water and the atmosphere and detoxification of a range of contaminants including pathogens. Much is known concerning the individual carbon, nitrogen and phosphorus (C, N and P) and contaminant cycles, however the coupling of these cycles through the landscape and the subsequent impacts on the natural environment and the services provided are rarely studied. To respond to this gap in our current understanding we will address two research questions. The first is when, where and how do coupled macronutrient cycles (of C, N and P) affect the the functioning of the natural environment within and between landscape units at the catchment scale? The second is how will these coupled cycles alter under land use, air pollution, and climate-change and what will be the effect on water quality, carbon sequestration and biodiversity (three important ecosyststem services) at both catchment and national scale? To achieve this, we will quantify the fluxes, transformations and coupling of the C, N, and P cycles through key processes (net primary productivity, decomposition, nutrient cycling) and quantify the links to pathogen transfer and viability using a combination of targeted field-based monitoring and field- and laboratory-based experimentation in the Conwy catchment supplemented by measurements in intensively farmed areas of the Ribble. The following outcomes are expected:1. Quantification and improved process-understanding of coupled C, N and P processes, transformations and fluxes across soil functional types and within processing hotspots. 2. Quantification of the effects of instream ecosystem function and co-limitation of N/P on eutrophication development in freshwaters.3. Testing of hypotheses that terrestrial and freshwater biodiversity can be explained at the catchment- and national-scales as function of macronutrient flux and primary productivity.4. Source to sea flux quantification and process-understanding of the fate of pathogens and the controls exerted by macronutrients within very fine sediments (flocs). 5. An integrated, parsimonious coupled macronutrient (C, N, P) air-land-water modelling platform, configured for a 1 km grid across the Conwy (i.e. an enhanced JULES model).6. Sensitivity analysis of carbon sequestration, water quality and biodiversity to past and future climate, nutrient and land (forest) cover change to determine the key controls on past and future changes in carbon sequestration, water quality and biodiversity.7. Quantification of trade offs in delivery of carbon sequestration, water quality and biodiversity at the catchment scale and the relationship to land cover type and climate regime.