Plants are a vital piece of healthy and sustainable wetland ecosystems. Plants are the base of the food chain and can build new layers of organic material on top of wetlands which helps them keep pace with subsidence and rising waters. Wetland vegetation reduces erosion primarily by dampening and absorbing wave and current energy and by binding and stabilizing the soil with roots. Coastal wetland plant species are indicators of soil and hydrologic conditions. The amount and salinity of water in an area influence which plants grow there. Scientists often classify Louisiana marshes into four types: fresh, intermediate, brackish, and saline.
The Coastal Wetlands Planning, Protection, and Restoration Act puts native wetland plant benefits to use through restoration techniques that include vegetative plantings. Vegetative planting projects are used both alone and in conjunction with barrier island restoration, marsh creation, shoreline protection, and sediment and nutrient trapping restoration techniques. These projects use flood-and salt-tolerant native marsh plants that will hold sediments together and stabilize the soil with their roots as they become established in a new area.
The Louisiana Environmental Education Commission, Louisiana Department of Wildlife and Fisheries, and the Louisiana Environmental Education Association hosted the 20th Environmental Education State Symposium on February 3-4, 2017 at the Embassy Suites by Hilton in Baton Rouge, La. The theme of this year’s symposium was “protecting Louisiana’s endangered species.”
The Louisiana Environmental Education Commission (LEEC) provides environmental education news from across Louisiana, including information on environmental education programs, workshops, and grant opportunities. The state symposium furnished opportunities for formal and non-formal environmental educators from Louisiana and surrounding states to meet and share teaching techniques as well as multiple concurrent sessions for various topics and grade levels. Keynote speaker Dr. Jessica Kastler, Coordinator of Program Development at the Gulf Coast Research Laboratory’s Marine Education Center, used individual cases of endangered species to engage the audience in explorations of the process of science while cultivating environmental stewardship. In addition to the keynote speech, presenters in 15 concurrent sessions provided lesson demonstrations, hands-on workshops, and/or exemplary programs. The Coastal Wetlands Planning, Protection, and Restoration Act Public Outreach Staff was among exhibitors with a multitude of materials to assist teachers of all grade levels in furthering their students’ knowledge in environmental education and coastal protection.
Plants of the wetlands are generally known to be highly dependent upon specific conditions, such as salinity, proximity to water, and vegetation type.
While some plants are able to adapt to condition alterations, other species do not overcome change as well. However, a major threat to all wetland vegetation is hydrilla.
Hydrilla is a non-native, invasive aquatic plant that has staked its claim by out-competing native plants and obstructing waterways. Hydrilla is a submerged, perennial plant that prefers freshwater, but can tolerate up to 7% salinity. This aggressive plant is known for clogging waterways, impeding natural flow, affecting human use such as fishing and seafood harvest, and clogging intakes and municipal drinking water supplies. Hydrilla can take over an area quickly as a result of its ability to multiply rapidly using four different strategies. Regrowth of stem fragments containing at least one node into a new plant, tubers on rhizomes producing new tubers, leaf turions that settle into sediment and form a new plant, and seed dispersal are all methods of reproduction for hydrilla. Hydrilla can out-compete native plants by its ability to tolerate low and high nutrient conditions in addition to growing in low light environments. Hydrilla is also successful in out-competing other plants by growing at a rate of one inch per day until reaching the water’s surface, followed by branching out to form a mat of vegetation which blocks light to other plants.
In order to control the growth of hydrilla, salvinia weevils have been released into severely affected areas. The salvinia weevil lives exclusively on hydrilla as a food source, thus reducing growth rates to allow control of the plant. The Coastal Wetlands Planning, Protection, and Restoration Act is currently researching the best, most beneficial method of controlling and eradicating invasive plant species.