ABSTRACT

Global change drivers including eutrophication, hydrological disturbance, climate change, chemical pollution, overexploitation, invasive species, and land-use change are affecting the function and structure of freshwater ecosystems. South American freshwater ecosystems are especially threatened by the combination of rising human pressures on natural resources (i.e., water use, intensive agriculture, mining, deforestation, and afforestation) and the lack of adequate legislation and economic resources for environmental protection and restoration. We assess the state of freshwater ecosystems in Argentina, Brazil, Chile, Colombia, Ecuador, Uruguay, and Venezuela, focusing on broad categories of human-induced threats grouped into 5 categories: climate change, watershed stressors, hydrological alteration, channel modification, and biological stressors. For most countries, the most severe threats are related to land uses such as mining, agriculture, and urban expansion. Other threats relate to the abstraction or wasteful use of water and the intense regulation of flows, including the effects of large hydraulic infrastructure. There is also an increasing need to empower public organisations that focus on environmental protection, to update or develop an adequate regulatory and legal framework, to provide adequate funding for the implementation of environmental legislation, and not least to implement ecological rehabilitation. Implementation of these steps would reduce the threats to South American aquatic ecosystems and allow progress toward the sustainable development of this region in future decades.

摘要

包括富营养化、水文干扰、气候变化、化学污染、过度开发、入侵物种和土地利用变化在内的全球变化驱动因素正在影响淡水生态系统的功能和结构。南美洲淡水生态系统尤其受到人类对自然资源（即用水、集约化农业、采矿、森林砍伐和植树造林）不断增加的压力以及缺乏用于环境保护和恢复的足够立法和经济资源的综合威胁。我们评估了阿根廷、巴西、智利、哥伦比亚、厄瓜多尔、乌拉圭和委内瑞拉的淡水生态系统状况，重点关注人类造成的威胁，分为 5 类：气候变化、流域压力源、水文改变、航道改造和生物压力源。对于大多数国家来说，最严重的威胁与土地利用有关，例如采矿、农业和城市扩张。其他威胁与取水或浪费用水以及对流量的严格监管有关，包括大型水利基础设施的影响。也越来越需要赋予关注环境保护的公共组织权力，更新或制定适当的监管和法律框架，为环境立法的实施提供足够的资金，尤其是实施生态恢复。这些步骤的实施将减少对南美水生生态系统的威胁，并在未来几十年推动该地区的可持续发展。和城市扩张。其他威胁与取水或浪费用水以及对流量的严格监管有关，包括大型水利基础设施的影响。也越来越需要赋予关注环境保护的公共组织权力，更新或制定适当的监管和法律框架，为环境立法的实施提供足够的资金，尤其是实施生态恢复。这些步骤的实施将减少对南美水生生态系统的威胁，并在未来几十年推动该地区的可持续发展。和城市扩张。其他威胁与取水或浪费用水以及对流量的严格监管有关，包括大型水利基础设施的影响。也越来越需要赋予关注环境保护的公共组织权力，更新或制定适当的监管和法律框架，为环境立法的实施提供足够的资金，尤其是实施生态恢复。这些步骤的实施将减少对南美水生生态系统的威胁，并在未来几十年推动该地区的可持续发展。也越来越需要赋予关注环境保护的公共组织权力，更新或制定适当的监管和法律框架，为环境立法的实施提供足够的资金，尤其是实施生态恢复。这些步骤的实施将减少对南美水生生态系统的威胁，并在未来几十年推动该地区的可持续发展。也越来越需要赋予关注环境保护的公共组织权力，更新或制定适当的监管和法律框架，为环境立法的实施提供足够的资金，尤其是实施生态恢复。这些步骤的实施将减少对南美水生生态系统的威胁，并在未来几十年推动该地区的可持续发展。