Opportunities and challenges for the sustainability of lakes and reservoirs in relation to the sustainable development goals (SDGs)

Emerging global threats, such as biological invasions, climate change, land use intensification, and water depletion, endanger the sustainable future of lakes and reservoirs. To deal with these threats, a multidimensional view on the protection and exploitation of lakes and reservoirs is needed. The holistic approach needs to contain not just the development of economy and society but also take into account the negative impacts of this growth on the environment, from that, the balance between the three dimensions can be sustained to reach a sustainable future. As such, this paper provides a comprehensive review on future opportunities and challenges for the sustainable development of lakes and reservoirs via a critical analysis on their contribution to individual and subsets of the Sustainable Development Goals (SDGs). Currently, lakes and reservoirs are key freshwater resources. They play crucial roles in human societies for drinking water provision, food production (via fisheries, aquaculture, and the irrigation of agricultural lands), recreation, energy provision (via hydropower dams), wastewater treatment, and flood and drought control. Because of the (mostly) recent intensive exploitations, many lakes and reservoirs are severely deteriorated. In recent years, physical (habitat) degradation has become very important while eutrophication remains the main issue for many lakes and ponds worldwide. Besides constant threats from anthropogenic activities, such as urbanization, industry, aquaculture, and watercourse alterations, climate change and emerging contaminants, such as microplastics and antimicrobial resistance, can generate a global problem for the sustainability of lakes and reservoirs. In relation to the SDGs, the actions for achieving the sustainability of lakes and reservoirs have positive links with the SDGs related to environmental dimensions (Goals 6, 13, 14, and 15) as they are mutually reinforcing each other. On the other hand, these actions have direct potential conflicts with the SDGs related to social and economic dimensions (Goals 1, 2, 3 and 8). From these interlinkages, we propose 22 indicators that can be used by decision makers for monitoring and assessing the sustainable development of lakes and reservoirs

Ghost of diadromous fish past: streamlining research on diadromous fish species using historical data at european scale

Doutoramento em Restauro e Gestão Fluviais - Instituto Superior de Agronomia / Faculdade de Arquitetura / Instituto Superior TécnicoThe decline of diadromous fish species has been occurring at least since the beginning of the 20th century. In this thesis, multiple European databases on the historical distribution of diadromous fish were consulted and, acknowledging the lack of data for Portugal, the first database of Portuguese historical data for freshwater fish was created. The existence of multiple databases with distinct geographical coverage and data at different spatial scales lead to the development of an historical data framework able to deal with the limitations of historical data. Its output is a reliable and geographically broad dataset of diadromous species occurrence at the beginning of the 20th century at three spatial scales: basin, sub-basin and segment. Also, a software was developed to facilitate the acquisition of environmental and riverscape variables that can be linked with the data at the three scales. Longitudinal connectivity impairment, climate change and land use alterations are some of the most significant threats to diadromous fish species. The influence of these threats was studied performing a spatial and temporal analysis of the longitudinal connectivity impairment by large dams and, modelling the distribution of diadromous fish at the beginning of the 20th century using climate and land use variables. The longitudinal connectivity impairment of the European freshwater networks became widespread in the second half of the 20th century, and is currently more impactful for populations from basins in southern Europe. The distribution of diadromous fish species is mainly affected by climate, though the effects of land use close to river mouths may be relevant since these are critical passage and entry points for the remaining network. The framework and the software developed were key to achieve the scientific knowledge presented, and more importantly, these can be established as the structural basis for future research on diadromous fish speciesN/