(361b) Managing Technological and Ecological Systems in a Watershed While Considering the FEW Nexus, Ecological Carrying Capacity, and the Effects of Climate Change

Accounting for the nexus of food-energy-water (FEW) is essential for sustainable management of watersheds. In addition, since the supply of natural resources is limited, it is also important to consider the carrying capacity of ecosystems that support the activities. For example, thermoelectric power plants, which provide electricity to other activities, are one of the largest contributors to total water consumption and greenhouse gas emissions. However, as the supply of water resources and carbon sequestration ecosystem service from nature is finite in the watershed, the supply of these ecosystem goods and services also needs to be considered for watershed sustainability. Similarly, farming produces food but releases significant amounts of nutrient emissions to the watershed where the supply of water quality regulation service is usually limited. To claim sustainability of a watershed, therefore, interactions between FEW flows and ecosystem flows need to be studied [1].

Considering the impacts of climate change is also crucial for sustainable watershed management. Various climate models (CMs) estimate future climate projections. Those CMs show that we may have an increased risk of water scarcity and warmer water temperature. Climate change could affect the FEW nexus and ecosystem in various ways [2]. For instance, thermoelectric power plants might be displaced by water efficient power plants, such as wind power generation to mitigate climate change. Farming practices may also be affected by climate change due to the change in crop productivity and water availability. Land use and land cover, such as type of vegetation, could be affected as well, and accordingly, causing changes in the supply of various ecosystem services [3].

In this work, we investigate the nexus of FEW and ecosystem capacity in the Muskingum River Watershed in Ohio by considering various technological and agroecological alternatives under current and future climate change scenarios. Technological alternatives include different non-renewable and renewable energy resources, cooling technologies, and CO2 conversion technologies. Technologies for converting CO2 into hydrocarbon products treat CO2 as a valuable resource and help in mitigation net CO2 emissions. Water resources are required to provide hydrogen to the hydrocarbons. Agroecological alternatives include different farming practices and land use changes. Such alternatives not only affect water quality and quantity in the watershed but also affect the provisioning of ecosystem services, such as CO2 sequestration in vegetation and soil. The Soil and Water Assessment Tool (SWAT) is used to explore the agroecological alternatives. The Techno-Ecological Synergy (TES) framework is applied to inspect if any environmental interventions (e.g., CO2 emissions) overshoot their corresponding ecological capacities (e.g., CO2 sequestration) [4].

Some alternatives may be superior in terms of environmental sustainability, but economically expensive. Thus, insights for the sustainable management of watershed are provided by identifying potential trade-offs between environmental and monetary objectives. Monetary values of ecosystem services are estimated to include non-market values of ecosystem services.

The findings of this work will provide insights into alternatives that are ‘win-win’ in terms of various objectives under several climate change scenarios. Preliminary findings of this study show that dry cooling technologies and no-till farming practice could reduce water quantity consumption and improve water quality while minimizing losses of energy and cost efficiencies. Further, this work could be applied to any watershed to help decision-making of businesses and policymakers to improve watershed sustainability and resilience to climate change.

References

[1] Bakshi, B.R., Gutowski, T.G., & Sekulic, D.P. Claiming Sustainability: Requirements and Challenges, ACS Sustainable Chemistry and Engineering, 6(3), 3632–3639 (2018).

[2] Berardy, A. & Chester, M.V. Climate change vulnerability in the food, energy, and water nexus: concerns for agricultural production in Arizona and its urban export supply. Environ. Res. Lett., 12 (2017).

[3] Schroter, D. et al. Ecosystem Service Supply and Vulnerability to Global Change in Europe. Science, 310, 1333-1337 (2005).

[4] Bakshi, B. R., Ziv, G., & Lepech, M. D. Techno-ecological synergy: A framework for sustainable engineering. Environ. Sci. Technol., 49, 1752–1760 (2015).