Believe it or not, even though we often think of forests having the most carbon since there is so much foliage and so many trees, old salt marshes that have been building up carbon for a long time tend to contain more carbon per acre because of all the buildup of dead plant material in the soil that never had time to decay.
The “Bay Grasses in Classes” program at Tampa Bay Watch aims to educate and inspire future scientists, environmentalists and enthusiasts by involving students from local schools in the Tampa Bay area with hands-on coastal wetland restoration. Nurseries for wetland grasses such as Spartina alterniflora and Paspalum vaginatum are established at these schools, and then the students and teachers cultivate them.
These nurseries are continuously used to produce plants for restoration purposes. After constructing a nursery onsite, a harvesting event is scheduled and the students join Tampa Bay Watch staff members in harvesting enough of a specific wetland grass to fill their nursery with plants. The next day, the students plant the grasses they harvested into the nursery that was built at their school. Over the next several months the students are responsible for looking after the grasses: taking salinity and pH readings, weeding the nursery, looking out for signs of common diseases. Students also learn about the environmental benefits of the grasses both from their teachers and from Tampa Bay Watch staff who travel to the schools on request in order to teach.
Once the plants have had enough time to double their population by seeding and by rhizomatic reproduction (roots that sprout new plants!), the students harvest half of the plants in the nursery and transplant those plants to a restoration site. Lastly, the plants that have been left over in the other half of the nursery are used to repopulate the whole area of the nursery. This involves harvesting the plants first, then splitting each of the groups of plants (called plugs) into two separate pots in the nursery.
Wetland plants provide unique benefits to marine, estuarine and coastal environments. Coastal wetland grasses have many small, fibrous roots that snake into the soil or sand and help to hold it in place, slowing the erosion that is so common in coastal areas.
Coastal wetland plants provide benefits for marine habitats by absorbing harmful materials in runoff. When runoff, full of pollution and nutrients, runs through the marsh, plants will uptake nutrients, lessening the impact they have on water quality.
Wetland grasses benefit water quality (and air quality!) with the uptake and storage of atmospheric carbon. When a plant dies in the forest, most of its carbon is released back into the air when the plant tissue is decomposed. Some wetland grasses live in the inter-tidal zone (above low tide and below high tide). Since the sediment is often either underwater or waterlogged, there is significantly less oxygen in it. Therefore, dead plant material (which is rich in carbon) takes a very long time to decay, causing a “carbon sink”.
In the BGIC program, our hope is that involving middle and high school students in the process of restoring native plants to create coastal habitat will give students the chance to see what working as a scientist or environmental worker might be like while simultaneously providing free plants restoration to local agencies. Ideally, the experience will inspire some students to pursue a career in a related field.
-Matt Flynn, Tampa Bay Watch