Sustainably Solving Legacy Phosphorus in Landscapes with Wetlands and Wetlaculture
The world is faced with unprecedented threats to our aquatic ecosystems from excessive nutrients caused especially by agricultural and urban runoff. More than 750 aquatic ecosystems in the world suffer from degraded ecosystem services with impairments described as hypoxia, dead zones, and harmful algal blooms, most due to pollution caused by excessive nitrogen and phosphorus. At the same time, it has been estimated that, on a global scale, we have lost half of our original wetlands to our current extent of 8 to 12 million km2 , with most of that loss in the 20th century. We are proposing here a sizeable increase in the wetland resources around the world to solve the diminishing wetland problem but with the strategic purpose of mitigating the excess phosphorus and nitrogen in a sustainable fashion. Examples include minimizing phosphorus inflows to the Florida Everglades with treatment wetlands and reducing nutrient inflows to Lake Erie in the Laurentian Great Lakes by restoring parts of the Great Black Swamp, formerly a 400,000-ha wetland west of Lake Erie. We have developed an approach referred to as “wetlaculture” (wetlands + agriculture) that uses a landscape of alternating wetlands and agriculture to solves downstream nutrient pollution problems while decreasing the amount of fertilizers added to landscapes every year by recycling. We have established three physical models (sets of twenty-eight 1-m2 mesocosms), two in temperate Ohio and one in subtropical south Florida, for estimating the amount of time that is needed for land to be wetland nutrient sinks for a given number of years as agriculture—a concept we refer to as landscape flipping. Early phosphorus results from our mesocosm wetlands in southeast Ohio started in 2016 (polluted Buckeye Lake in Ohio River basin), in northwest Ohio started in 2017 (near polluted Lake Erie), and south Florida in 2018 (analog of the Florida Everglades) will be presented. In addition to early water quality results and nutrient retention rates of wetlands in these 3 locations, we will present the first version of our business model that suggests an approach where farmers could make profits comparable to crop income if current or anticipated government subsidies, e.g. wetland reserve program (WRP) or payment for ecosystem services (PES) were coupled with Environmental Impact Bonds sold to investors.
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Citation / Publisher Attribution
Presented at the Greater Everglades Ecosystem Restoration Science Conference, Science Advancing Everglades Resilience and Sustainability, April 2019, Coral Springs, FL
Scholar Commons Citation
Mitsch, William J.; Jiang, Bingbing; Zhang, Li; Miller, Sam; and Bakshi, Bhavik, "Sustainably Solving Legacy Phosphorus in Landscapes with Wetlands and Wetlaculture" (2019). School of Geosciences Student Publications. 68.