Dataset: Thalassia testudinum belowground carbohydrate measurements from experimental plots in the Western Atlantic from Winter 2019 (Tropicalization Seagrass Beds project)

Sampling details

Small seagrass plots (0.25m2, all comprised of one species, Thalassia testudinum) were established at 9 shallow sites in the western Atlantic. Each plot was assigned to one of two treatments (n=5/treatment): (1) control plot or (2) plots with the canopy fully clipped. Plots were maintained for 12 months, and at the end, seagrass biomass cores (15cm in diameter) were used to harvest belowground plant material in each plot. Belowground biomass (rhizomes only) were separated from all other material, dried to a constant weight in a 60C oven and ground to a fine powder. This belowground material was then sent to the UC Davis plant lab for the analysis of total soluble carbohydrates (glucose, fructose, sucrose) following the protocols of Smith (1969).

Total Glucose for Total Nonstructural Carbohydrate (TNC) and Startch Methods Summary

The dataset shows soluble carbohydrates expressed as a percentage of belowground dry mass. Nonstructural carbohydrates are those that can be accumulated and then readily mobilized in order to be metabolized or translocated to other plant parts. This method quantitatively determines the amount of the total glucose following enzymatic hydrolysis. Total non-structural carbohydrates (TNC) is the sum of total glucose, free fructose and free sucrose. Starch is the total glucose minus the free glucose multiplied by 0.9. The free carbohydrates are determined by a separate analysis. The samples for total glucose are enzymatically hydrolyzed at 55°C with amyloglucosidase for 12 hours and analyzed by HPLC with mass selective detection. The analysis uses a Phenomenex Luna NH2 (250 mm x 4.6 mm) HPLC column at a flow rate of 2.75 mL min-1 acetonitrile:water (78:22).

The method has a detection limit of 0.5% and is reproducible to within 10% (relative).

Smith, Dale. Removing and Analyzing Total Nonstructural Carbohydrates from Plant Tissue. Wisconsin Agric. Exp. Sta. Res. Report 41. 1969.

Site location details

ANDR: Andros, Bahamas (24°53'54.3" N, 77°54'25.2" W)

BERM: Bailey's Bay, Bermuda (32°15'49.9" N, 64°49'50.5" W)

BOCA: Bocas Del Toro, Panama (9°21'05.8" N, 82°15'27.8" W)

BONA: Lac Bay, Bonaire (12°06'44.3" N, 68°13'42.0" W)

CARR: Carrie Bow Cay, Belize (16°49'24.8" N, 88°06'16.2" W)

CAYM: Little Cayman, Cayman Islands (19°40'14.6" N, 80°03'21.3" W)

CORP: Corpus Christi, TX (27°55'47.9" N, 97°02'05.2" W)

CRYS: Crystal River, FL (28°42'50.4" N, 82°49'08.4" W)

ELEU: Eleuthera, Bahamas (25°27'53.5" N, 76°37'35.8" W)

GALV: Galveston, TX (29°02'41.8" N, 95°10'15.7" W)

JOES: St. Joe's Bay, FL (29°42'05.0" N, 85°19'34.6" W)

NAPL: Naples, FL (26°29'48.6" N, 82°09'40.0" W)

PUER: Puerto Morelos, Mexico (20°52'04.5" N, 86°51'35.4" W)