Osborne Lab Paper Reveals Product to Enhance Seagrass Restoration
Published: Tuesday, November 8, 2022
Congratulations to Osborne Lab Postdoctoral Research Associate Conor MacDonnell, Ph.D., Todd Osborne, Ph.D., Anna Beard, and colleagues who published a paper in Science of the Total Environment -"Use of a wastewater recovery product (struvite) to enhance subtropical seagrass restoration." The study has been featured in several news stories with links below.
Highlights
• Seagrass restoration is currently expensive and often unsuccessful.
• Fertilizers improve restoration but can release excess nutrients.
• Osmocote™ and struvite fertilizers were investigated for plant and nutrient metrics.
• Struvite produced higher seagrass metrics and released less nutrients.
Full Paper in Science of the Total Environment
In the News
Gainesville Sun - University of Florida study shows human pee could play key role in seagrass restoration
A new University of Florida study has found that a byproduct of human pee can play a pivotal role in the restoration of seagrasses, which contributes heavily to the marine ecosystem.
Article - University of Florida study shows human pee could play key role in seagrass restoration
IFAS Blog - Could your body be storing the key to saving seagrass?
A new University of Florida study applied struvite to seagrass plots and found the method to provide better growth over time, in addition to environmental and sustainability benefits.
Article - Could your body be storing the key to saving seagrass?
Futurity - Our Pee Could Help Bring Back Seagrass
A crystallized version of human urine could revitalize seagrasses, which provide food, habitat, and shelter in their ecosystems.
Article - Our Pee Could Help Bring Back Seagrass
Science of the Total Environment Paper Abstact
Seagrasses are in decline worldwide, and their restoration is relatively expensive and unsuccessful compared to other coastal systems. Fertilization can improve seagrass growth in restoration but can also release nutrients and pollute the surrounding ecosystem. A slow-release fertilizer may reduce excessive nutrient discharge while still providing resources to the seagrass's rhizosphere. In this study, struvite (magnesium ammonium phosphate), a relatively insoluble, sustainable compound harvested in wastewater treatment plants, was compared to Osmocote™ (14:14:14 Nitrogen: Phosphorus: Potassium, N:P:K), a popular polymer coated controlled release fertilizer commonly used in seagrass restoration. Two experiments compared the effectiveness of both fertilizers in a subtropical flow-through
mesocosm setup. In the first experiment, single 0.5 mg of P per g dry weight (DW) doses of Osmocote
™ and struvite fertilizers were added to seagrass plots. Seagrass shoot counts were significantly higher in plots fertilized with struvite than both the Osmocote™ and unfertilized controls (p < 0.0001). A significant difference in total P concentration was observed in
porewater samples of Osmocote
™ vs struvite and controls (p < 0.0001), with struvite fertilized plots emitting more than controls (p ≤ 0.0001), but less than 2% of the total dissolved P (TDP) of Osmocote™ fertilized plots (100+ mg/L versus x > 5 mg/L). A subsequent experiment, using smaller doses (0.01 and 0.025 mg of P per gram DW added), also found that the struvite treatments performed better than Osmocote™, with 16–114% more aboveground biomass (10–60% higher total biomass) while releasing less N and P. These results indicate the relatively rapid dissolution of Osmocote™ may pose problems to restoration efforts, especially in concentrated doses and possibly leading to seagrass stress. In contrast, struvite may function as a slow-release fertilizer applicable in seagrass and other coastal restoration efforts.
The Whitney Laboratory for Marine Bioscience
