About this Research Topic
Drylands cover more than 45% of the Earth's terrestrial surface area, being home to over 2 billion people. To date, seven of the world’s 35 diversity hotspots are located in arid regions. Nevertheless, these environments are highly threatened by multiple anthropogenic stressors (climate change and impacts of human activities during the Anthropocene). Dryland rivers are fascinating systems because they flow through arid or semi-arid regions characterized by variable flow regimes, including intermittent and unpredictable flows, and are inhabited by a uniquely adapted biota. These ecosystems are increasingly subjected to climatic variability and stress regimes, including increased intermittency, delay in the onset of the rainy season, higher temperatures and evapotranspiration rates, prolonged droughts, and low rainfall associated with climate change, in addition to Anthropocene human impacts leading to habitat deterioration and ecosystem decline. However, surprisingly, the combined effects of human activities and climate change on dryland rivers have been little studied to date.
Drylands are characterized by special conditions in climate, soil properties, and hydrologic conditions such as the high inter-annual variability in the rainfall regime. Perennial, intermittent, and ephemeral streams with marked variations in permanence throughout the year can be found in the same catchment. In combination with climate change impacts and an increasing impacts from anthropogenic land use, these environmental conditions have significant consequences for aquatic communities. In drylands, however, the importance of natural environmental drivers relative to anthropogenic stressors and climate change, and their particular relative effects on water quality, biota, and ecosystem processes remain poorly understood.
Recent advances in tools and more comprehensive field research and monitoring programs have contributed to our understanding of the relationships between climate change, human effects, and changes in land use on geological features, soils, water quality, biodiversity, and ecosystem processes. These advances provide unique opportunities for the comprehensive analysis of dryland river characteristics, biodiversity, and ecological functioning under multiple stressor syndromes.
This Research Topic aims to provide an overview and specific case studies of research on dryland rivers with the following objectives: (i) increase understanding of the processes that take place in natural and human-impacted dryland rivers; (ii) collate and display the tools available to assess the effects of multiple stressors on dryland rivers, (iii) advance knowledge of the biodiversity and adaptation mechanisms of aquatic biota in dryland rivers, and (iv) review conservation and restoration strategies for these ecosystems.
This Research Topic welcomes contributions in the categories of Original Research Articles, Perspectives, and Review Articles that can boost interdisciplinary environmental research focused on dryland rivers and their restoration/conservation. The scope includes:
-Spatio-temporal variability assessment of hydrology, water quality and aquatic biota, and identification of the key drivers of dryland community structure and ecosystem processes
-Hydrological patterns, variability and community processes
-Adaptation mechanisms of aquatic biota to dryland river conditions
-Responses of aquatic biota to human induced changes in dryland river conditions
-Integration of long-term monitoring data documenting the effects of climate change on dryland rivers
-Novel approaches for the integration of different stressors (changes of land use, climate change, and environmental consequences) across multiple sites using statistical and modelling tools
-Sustainable use, restoration, and conservation strategies for dryland rivers
Photo Credit: M. en C. Jacinto Elías Sedeño Díaz
Keywords: dry land rivers, water quality, freshwater communities, vulnerability, conservation, adaptation, hydrological variability, climate change, biodiversity
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.