The Watershed Flood Center

On May 4, 2018, the University of Louisiana introduced an important new venture: The Watershed Flood Center. [1] In response to massive flooding in August of 2016 in Southern Louisiana, experts will come together to develop a better understanding of flooding in the area. Torrential downpours hit the state consistently on August 12 and 13 of 2016, amounting to more than 31 inches in Watson, LA, and more than 20 inches in Lafayette, the new home base for the Center. Atmospheric conditions caused a series of storms to form and stay over southern Louisiana for those two days, dropping and estimated 2 inches of water per hour. [2] Across the state, an estimated 7.1 trillion gallons of rain came down on August 12^th and 13^th, more than three times the volume Louisiana received during Hurricane Katrina in 2005.  The flooding caused an estimated $10-15 billion dollars in damages across the affected parishes, including almost 150,000 homes and businesses. [3] This catastrophe was called a 1-in-1000-year flood because meteorologists attributed a .1% chance to something of this scale happening in any given year based on past events. The Watershed Flood Center seeks to study how much that chance may be increasing with projected changes in atmospheric and climatic conditions.

Basins that will be researched at the new center | Source [1]

Wetlands are adapted to flooded conditions, so they are great for mitigating floodwaters. Mitigation allows water to be stored and released when needed, so they act like a sponge. Unfortunately, the sheer volume of water that came and stayed was too much to redirect into neighboring wetlands. Wetlands used to be more prominent but as towns and cities expand into wetlands, mitigation potential of those wetlands diminishes. Thanks to development and decreased wetland area, much of the flooded area was inundated and impassable for over a week even after the rain had stopped.

The new center at The University of Louisiana at Lafayette is far from the only research venture the university funds. ULL has many research centers and partners, including LUMCON, the Ecology Center, and the Informatics Research Institute, to name a few. These centers study many branches of science, including infectious diseases, immersive technologies, ion beams, and soon the list will include the flood-condition hydrology of Louisiana. The Watershed Flood Center is currently in development and, once completed, will study flood events with real-time monitoring to develop better forecasts to protect public interests. [4]

 

[1] https://thecurrentla.com/2018/a-new-flood-research-center-launched-to-put-fractured-regional-efforts-on-the-same-page/

[2] https://en.wikipedia.org/wiki/2016_Louisiana_floods

[3] https://weather.com/forecast/regional/news/rain-flood-threat-south-mississippi-ohio-valley

[4] https://floodcenter.louisiana.edu/research/projects

Featured image from http://www.theadvocate.com/louisiana_flood_2016/article_dbfba072-7148-11e6-a7b4-0f0b3863c31e.html

Stress Part II: Flooding and Hypoxia

Wetland inhabitants must also deal with flooding stress. All parts of a plant must have oxygen, which causes problems when a plant is rooted in hypoxic soils and it is flooded. Gases diffuse about 10,000 times more slowly through water than through air, and wetland soils are often inundated and hypoxic. This poses an issue for supplying roots with enough oxygen since they don’t have any around them. Some root systems will have adventitious roots, which means they extend above the surface of the water or soil to allow gas exchange with the atmosphere.[1] Red mangroves have prop roots, black mangroves have pneumatophores, and both supply oxygen directly to the root system rather than relying on transport all the way from the leaves to the roots.[2]

Hypoxia can be caused by eutrophication and decomposition. Hypoxia and anoxia are dangerous to most plants and animals because most cannot live only with anaerobic (without oxygen) respiration. Bacteria can sometimes live in anoxic conditions by using different electron receptors that are more plentiful in wetland soils like sulfates. Plants can sometimes cope with hypoxia thanks to adaptations like aerenchyma development in their roots. Aerenchymous tissues are much more porous to allow gases to diffuse up to 30 times more easily through a plant! In animals, lungs can allow some fish, mammals, and aquatic gastropods (snails) to live in hypoxic waters, but many fish have gills that are not adapted to hypoxia. The Gulf of Mexico along Louisiana’s coast boasts one of the largest hypoxic zones in the world with a peak area of over 8,500 square miles in 2017, where many commercial fisheries have seen a large decline in fish catch. [3]

Photo from NOAA, Dead Zone 2017

Works Cited:

[1] Gilman, Sharon. “Plant Adaptations.” ci.coastal.edu/~sgilman/778Plants.htm.

[2] “Adaptations.” Adaptations :: Florida Museum of Natural History, http://www.floridamuseum.ufl.edu/southflorida/habitats/mangroves/adaptations/.

[3] “Gulf of Mexico ‘Dead Zone’ Is the Largest Ever Measured.” Gulf of Mexico ‘Dead Zone’ Is the Largest Ever Measured | National Oceanic and Atmospheric Administration, web.archive.org/web/20170802173757/http:/www.noaa.gov/media-release/gulf-of-mexico-dead-zone-is-largest-ever-measured.

Featured image is of Rhizophora mangle (red mangrove) from Flickr by barloventomagico