Biodiversity and ecosystem multifunctioning in rivers with modified flow regimes

“河流流量的调节是影响全球河流生态系统的最大压力因素之一。因此，在许多西方国家，主要的立法努力支撑着新方法的发展，以减轻河流流量管制的影响。这些方法的基础是优化河流流量的管理，以维持对人类的服务（例如供水、水电），同时在空间和时间上保护和/或使水环境恢复足够数量和质量的水（即环境流量）。在这种情况下，应用水生科学领域已经发展起来，为确定管理环境流量的数量、质量和模式以维持河流生态系统的最佳方法提供了证据基础。环境流动是最近提出的阻止和扭转全球淡水生物多样性下降的第一选择，这一领域的重要性得到了最好的例证。尽管最近的研究取得了许多进展，但仍然存在重大的知识空白，这阻碍了对河流流动动力学如何驱动生态过程的充分理解。例如，许多研究集中在单个生物群体（如鱼类、无脊椎动物）上，但相对较少的研究考虑到这些群体内部和群体之间物种相互作用的重要作用。其他生物群体，如微生物和初级生产者受到的关注相对较少。同样，对生态系统功能过程（如有机质和养分循环）的研究较少。这些研究差距提供了多种查询线的潜力，研究的具体重点是量身定制，以适应成功候选人的技能和兴趣。博士学位的主要目的是增加对河流管理如何通过调节水流制度影响河流生态系统的结构（如藻类/大型无脊椎动物的生物多样性）和/或多功能（如生产，分解，碳循环）的理解。这一领域知识的缺乏给河流管理者带来了问题，他们面临着确定和实施管理措施（包括环境流量）的压力，这是改善河流质量和实现生物多样性目标的一种方式。因此，研究结果将有可能通过与水务公司和水电等企业以及环境保护机构等监管机构的合作，为河流的保护目标提供信息。具体来说，该项目将检查环境流量在多大程度上可以用来增强河流生态系统，例如，将‘控制’地点（没有监管或有水库但没有可变环境流量的地点）与水库运营商正在进行试验的河流进行比较，这些试验方法包括恢复季节性洪水流量，和/或引入季节性可变补偿释放。”

"The regulation of river flows is one of the biggest stressors affecting river ecosystems across the world. In many westernised countries, major legislative efforts are therefore underpinning the development of new approaches to mitigate the impacts of river flow regulation. These approaches are based on optimising the management of river flows to maintain services to humans (e.g. water supply, hydropower) whilst protecting and/or rejuvenating the aquatic environment with water of adequate quantity and quality in space and time (i.e. environmental flows). In this context, a field of applied aquatic science has developed to generate the evidence base for identifying the best ways to manage the quantity, quality and patterns of environmental flows to sustain river ecosystems. The importance of the field is best exemplified by environmental flows being the number 1 option put forward recently as a way to halt and reverse global freshwater biodiversity declines.Despite numerous recent research advances, there are still significant knowledge gaps that prevent a full understanding of how river flow dynamics drive ecological processes. For example, many studies have focused on individual groups of organisms (e.g. fish, invertebrates) but relatively few have factored in the important role of species interactions within and between these groups. Other biotic groups such as microbes and primary producers have received comparatively less attention. Similarly, less research has been undertaken on ecosystem functional processes such as organic matter and nutrient cycling. These research gaps offer the potential for multiple lines of enquiry, with the specific focus of the study being tailored to suit the skills and interests of the successful candidate. The main aim of the PhD will be to increase understanding of how river management by regulation of flow regimes influence the structure (e.g. algae/macroinvertebrate biodiversity) and/or multifunctioning (e.g. production, decomposition, carbon cycling) of river ecosystems. The paucity of knowledge in this field is creating problems for river managers who are under pressure to identify and implement management measures (including environmental flows) as a way of improving river quality and in reaching biodiversity goals. Therefore, findings will have the potential to inform conservation targets for rivers through collaboration with businesses such as water companies and hydropower, and regulators such as environmental protection agencies. Specifically, the project will examine the extent to which environmental flows can be used to enhance river ecosystems, for example comparing 'control' sites (with either no regulation or sites with reservoirs but no variable environmental flows) against rivers in which reservoir operators are undertaking experiments through approaches such as reinstating seasonal flood flows, and/or introducing seasonally variable compensation releases."