Location: Invasive Plant Research Laboratory
Project Number: 6032-22000-012-061-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Jul 1, 2019
End Date: Aug 30, 2020
Objective:
1. Construct artificial aquatic communities consisting of native submerged, emergent, and floating aquatic vegetation and initiate the invasion of waterhyacinth into a subset of them.
2. Document the community interactions within each mesocosm before and after treatments are applied.
Approach:
This experiment is envisioned to last three years in order to capture the effects of waterhyacinth on plant communities over the longer term. The experimental design will be a randomized complete block design with two treatments replicated four times using 8 mesocosms.
Each mesocosm will be equipped with a stovepipe drain to standardize water depths. Initially, aquashade and tadpoles will be applied to reduce algal growth and killifish introduced to control mosquito populations. Aquatic communities will be constructed along a littoral to limnetic gradient and consist of emergent, submerged, and floating plant species. Shorelines will originate at one of the 3m sides of each mesocosm with the location chosen at random (east vs west). All plants except floating species will be grown in plots and placed at proper depths on cinderblocks. Following their placement, plants will be permitted to establish before capturing data. Cinderblocks supporting plant pots will be arranged in rows from the shoreline to deeper water to allow easy access for sampling.
Data will be captured periodically via destructive and non-destructive subsampling and include water quality, plant, and animal metrics. Water quality will include temperature and dissolved oxygen, plant metrics will include number of stems, number of leaves, height and width of potted plants, biomass or numbers of floating plants, and algal biomass. Following establishment and standardization of communities, waterhyacinth will be introduced into 4 of 8 tanks and allowed to grow. At the end of the experiment, all plants will be subsampled for herbivores and predators, harvested, weighed, and evaluated for nutrient contents. Plant litter will also be recovered, dried, and weighed.
