Biodiversity and ecosystem multifunctioning in rivers with modified flow regimes

“河流流量的调节是影响世界各地河流生态系统的最大压力因素之一。因此，在许多西化国家，主要的立法努力正在为开发新的方法来减轻河流流量管制的影响奠定基础。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)，同时保护和/或恢复水环境，在空间和时间上具有足够数量和质量的水(即环境流量)。在这方面，开发了一个应用水产科学领域，以产生证据基础，以确定管理环境流量、质量和模式的最佳方法，以维持河流生态系统。该领域的重要性最好的例证是环境流是最近提出的阻止和扭转全球淡水生物多样性下降的头号选择。尽管最近取得了许多研究进展，但仍然存在重大的知识差距，阻碍了对河流流动动态如何驱动生态过程的充分理解。例如，许多研究侧重于单个生物群体(如鱼类、无脊椎动物)，但相对较少考虑到这些群体内部和之间的物种相互作用的重要作用。微生物和初级生产者等其他生物群体受到的关注相对较少。同样，对有机质和养分循环等生态系统功能过程的研究也较少。这些研究空白提供了多条调查路线的可能性，研究的具体重点被量身定做，以适应成功候选人的技能和兴趣。该博士学位的主要目的将是增进对河流管理的理解，通过调节水流系统如何影响河流生态系统的结构(例如藻类/大型无脊椎动物生物多样性)和/或多功能(例如生产、分解、碳循环)。这一领域知识的匮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，以此作为改善河流质量和实现生物多样性目标的一种方式。因此，这些发现将有可能通过与自来水公司和水电等企业以及环境保护机构等监管机构的合作，为河流保护目标提供信息。具体而言，这项计划将研究环境流量可在多大程度上用来改善河流生态系统，例如将“控制”地点(没有管制或有水库但没有可变环境流量的地点)与水库营运者正在进行试验的河流进行比较，例如恢复季节性洪水流量，及/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."