Department of Aquatic System, Faculty of Environmental Sciences, and EULA Centre, Universidad de Concepción, Concepción, Chile.
Department of Aquatic System, Faculty of Environmental Sciences, and EULA Centre, Universidad de Concepción, Concepción, Chile.
Sci Total Environ. 2020 Apr 20;714:136735. doi: 10.1016/j.scitotenv.2020.136735. Epub 2020 Jan 15.
Massive exploitation of freshwater systems for hydropower generation in developing countries is challenging sustainability due to cumulative environmental impacts in regions with high endemism. Habitat fragmentation is recognized as a major impact on river ecosystems. The nature and magnitude of connectivity loss depend on characteristics of the hydropower projects, and of the threatened fish communities. In areas where appropriate mitigation technology is lacking, there is a need to identify the fish species that are most at risk to better concentrate efforts. This paper aimed to set conservation priorities for sustainable hydropower development by analyzing native fish species and project characteristics. The Chilean ichthyogeographic province, an ecoregion with high endemism and massive hydropower projects development, has been considered as a case study. By using overlapping information on the characteristics of 1124 hydropower projects and distribution of native fish species, we identified three project categories of projects based on their need for mitigation. These were projects where mitigation was considered: a) not required (15%), b) required and feasible (35%), and c) required but challenging (50%). Projects where mitigation was not required were located at sites where native fish were absent and/or where water intakes allowed fish to pass. Interestingly, projects where mitigation was feasible were inhabited by a species assemblage that comprised the genus Trichomycterus, Diplomystes and Percilia, and the species Ch. pisciculus and B. maldonadoi. This finding emphasizes the need to develop a multispecific fishway that can accommodate this group. Projects where mitigation would be difficult to achieve were located at sites with a variety of different assemblages, thus making a standard fish pass solution challenging and site-specific. This study advances understanding for the need to develop mitigation strategies and technologies in ecoregions of high endemism threatened by hydropower and to prioritize the construction of planned projects.
发展中国家大规模开发淡水资源用于水力发电，对高特有地区的环境造成了累积影响，对可持续性构成了挑战。生境破碎化被认为是对河流生态系统的主要影响。连通性丧失的性质和程度取决于水电项目和受威胁鱼类群落的特征。在适当的缓解技术缺乏的地区，需要确定最有风险的鱼类物种，以便更好地集中精力。本文旨在通过分析本地鱼类物种和项目特征，为可持续水电开发设定保护重点。智利的鱼类地理省是一个特有性高、大规模水电项目开发的生态区，被视为一个案例研究。通过使用 1124 个水电项目特征和本地鱼类分布的重叠信息，我们根据其缓解需求将项目分为三类。这些项目包括：a）不需要缓解（15%）、b）需要且可行缓解（35%）和 c）需要但具有挑战性的缓解（50%）。不需要缓解的项目位于没有本地鱼类且/或进水口允许鱼类通过的地点。有趣的是，可行缓解的项目栖息着一个由 Trichomycterus、Diplomystes 和 Percilia 属以及 Ch. pisciculus 和 B. maldonadoi 种组成的物种组合。这一发现强调了需要开发一种能够容纳该组合的多物种鱼类通道。难以实现缓解的项目位于具有各种不同组合的地点，因此使标准鱼类通道解决方案具有挑战性和特定于地点。本研究有助于理解在受水电威胁的高特有地区需要制定缓解策略和技术，并优先建设规划中的项目。
