Research OverviewOur research examines the effects of environmental change processes on aquatic systems ecology and management across geographic regions and scales.
Aquatic systems are undergoing rapid and extensive environmental change. Human-driven land cover changes, hydrological alteration, non-native species, pollution, overfishing, and climate change are recognized as serious threats to freshwater systems. Our lab applies a range of interdisciplinary approaches to investigate ecosystems and biodiversity responses to these major stressors and to propose solutions to conservation problems at local, regional, and global levels. These approaches include theories and tools from the fields of community, population and ecosystems ecology, functional ecology, food webs and stable isotope ecology, fisheries management and governance, and common pool resources.
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Land cover and habitat changes
Our research has investigated land cover changes effects on fishery yields, fish biomass distribution, assemblage structure and functional diversity as well as on aquatic food webs in the Amazon.
Human-driven land cover changes are a primary driver of endangerment for ~ 80% of vertebrate taxa globally, and poses significant degradation for aquatic fauna. Loss of riparian vegetation can impact aquatic organisms by reducing energy and nutrient subsidies and altering water quality and habitat (Arantes et al. 2018, 2019a). In large rivers, such as the Amazon, large forest areas are being cleared for development of agriculture, hydropower, and human settlement. Clearcutting and mountaintop mining practices have also caused dramatic landscape-scale disturbance with changes in the quality, movement, and storage of water in the US (e.g., Miller and Zégre 2014). Understanding the mechanisms through which land cover changes or deforestation affect aquatic ecosystems is therefore a research priority.
Dams and hydrological changes
Based on a functional traits approach, our project demonstrated that dams affected the functional composition of fisheries yields and reduced catches, negatively affecting fishing-based income of communities in the Amazon. This project is continuing to address dams impacts on Amazonian rivers, including in the Madeira and Xingu. Our lab is also investigating fishes responses to dam removal in West Virginia.
Dam construction disrupts lateral and longitudinal connectivity of rivers, alter flow regimes and sediment transport, thereby, impacting aquatic biodiversity and production worldwide. In addition to dams, culverts, and waterways construction are ubiquitous anthropogenic features across human-modified landscapes globally. These structures have been leading to shifts in spatial temporal patterns in the structure and diversity of aquatic communities and impeding movements necessary for species growth, survival, reproduction, gene flow, and colonization. Improved understating of the impacts of hydrological changes on aquatic systems is imperative to mitigate the social and ecological effects of these infrastructure projects.
Overfishing
Our research examines fishery impacts on fish populations and assemblages and identifies management strategies that can maintain healthy fisheries and livelihoods. Some of the research have focused on Arapaima, the Amazon’s most important and most overexploited fish. Check them out in Publications.
Overfishing has been the subject of much recent concern, with numerous fish stocks and other aquatic species declining and even collapsing in the last few decades. About 1 billion people rely on aquatic organisms as their primary source of protein and income, particularly, in developing countries. In the Mekong basin, the average consumption of fish and other aquatic animals is estimated at 56 kilograms per capita per year. In the Amazon, it averages 94 kg/yr in riverine populations and 40 kg/yr in urban populations, rates that are 5.8 and 2.5 times above the world average, respectively. Despite this importance, the discussion/data of the current fisheries crisis has focused mostly on marine resources, leaving open questions regarding the effects of overfishing in inland waters. In particular, there is a urgent need to understand the extent overfishing has been occurring and its effects on biodiversity, ecosystems processes, and people's livelihoods.
Climate change
Currently, we are investigating aquatic species vulnerability to Climate Change in WV. We assessed species, communities, and habitats’ vulnerability and built a user-friendly tool that enable identifying aquatic species and habitats of great concern. In another project (USGS CASC) we will model current and future spatial distributions of high priority species by using known location records and associated climate, environmental, and land-use data. Find out more information about this project in the ScienceBase page and in the CACS Project Explore page.
As we enter the 21st century, climate change has been increasingly recognized as a serious threat to freshwater systems. Climate change has been inducing changes in thermal regimes across globally. Climate change models have also predicted changes in precipitation regimes. For example, whereas rainfall is expected to increase in the mountainous regions of the Central Appalachian, it is likely to decrease in the southwest region. These changes in rainfall and temperature patterns have serious implications for the hydrological budget of aquatic systems and their intrinsically linked terrestrial systems, resulting in varying vulnerabilities to aquatic habitats and ecological communities that must be understood.
Invasive Species
In a current project, we are examining factors driving and limiting the expansion of Invasive Carps in large rivers in the US with emphasis on the Tennessee/Cumberland and Ohio Rivers . The project will identify and model hydrologic dynamics and watershed characteristics influencing year class strength, carp populations, and ecosystems processes. This project is a collaboration with Dr. Brent Murry's Lab and state and US federal agencies (USGS-Tennessee Tech Coop Unit, KY DNR, WV DNR, and IN DNR).
Non-native species have modified habitats, and affected native biodiversity and food webs. In addition to their ecological impacts, invasive species cost of control efforts are enormous each year (e.g., about 10 million/year for controlling lampreys in the Great Lakes). Despite progress on invasive species research, there is still a need to improve understanding on the impacts of many invasive species on native species and on ecosystem function.
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[more information will be available soon on 'Projects']
[more information will be available soon on 'Projects']