Coastal Sediment Nutrient Enrichment Alters Seagrass Blue Carbon Sink Capacity.
Environ Sci Technol
; 55(22): 15466-15475, 2021 11 16.
Article
in En
| MEDLINE
| ID: mdl-34698488
ABSTRACT
The seagrass ecosystem is among the most efficient natural carbon sinks that can contribute to climate change mitigation. However, little is known about the effects of coastal nutrient enrichment caused by anthropogenic activities and/or climate change on the capacity of the seagrass blue carbon sink. Our experimental manipulations of sediment nutrient enrichment shifted the blue carbon sink capabilities of seagrass meadows. Sediment nutrient enrichment significantly increased the nutrient content of seagrass litter, stimulating the decomposition of rhizome + root litter by â¼10% while retarding the decomposition of leaf litter by â¼5%. Sediment N + P enrichment increased seagrass growth and litter production, while enrichment of N or P alone did not. Organic carbon (Corg) stocks in the surface sediments (0-5 cm) were 34% higher than those in the control with N + P enrichment due to high litter production and the low decomposition rate of nutrient-enriched leaf litter. However, Corg stocks in the subsurface sediments (5-20 cm) did not increase with sediment nutrient enrichment, which is likely due to accelerated decomposition of rhizome + root litter. Our findings suggest that nutrient loading in coastal sediments alters the blue carbon sink and storage capacities in seagrass meadows by changing the rates of carbon sequestration and decomposition.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Ecosystem
/
Carbon Sequestration
Language:
En
Journal:
Environ Sci Technol
Year:
2021
Document type:
Article