Artificial reefs concentrate nutrients and alter benthic community structure in an oligotrophic, subtropical estuary

The construction of artificial reefs in the oligotrophic seagrass meadows of central Florida Bay attracted large aggregations of fish and invertebrates, and assays of nutrient availability indicated increases in availability of nutrients to sediment microalgae, periphyton, and seagrasses around reefs. An average of 37.8 large (> 10 cm) mobile animals were observed on each small artificial reef. The dominant fish species present was the gray snapper (Lutjanus griseus Linnaeus, 1758). Four yrs after the establishment of the artificial reefs, microphytobenthos abundance was twice as high in reef plots (1.7 ± 0.1 μg chl-a cm-2) compared to control plots (0.9 ± 0.1 μg chl-a cm-2). The accumulation of periphyton on glass periphytometers was four times higher in artificial reef plots (200.1 ± 45.8 mg chl-a m-2) compared to control plots (54.8 ± 6.8 mg chl-a m-2). The seagrass beds surrounding the artificial reefs changed rapidly, from a sparse Thalassia testudinum (Banks & Soland. ex König) dominated community, which persisted at control plots, to a community dominated by Halodule wrightii (Ascherson). Such changes mirror the changes induced in experimentally fertilized seagrass beds in Florida, strongly suggesting that the aggregations of animals attracted by artificial reefs concentrated nutrients in this oligotrophic seascape, favoring the growth of fast-growing primary producers like microphytobenthos and periphyton, and changing the competitively dominant seagrass from slow-growing T. testudinum to faster-growing H. wrightii in the vicinity of the reefs.

Inadequacy of Micronutrients, Fat, and Fiber Consumption in the Diets of Haitian-, African- and Cuban-Americans with and without Type 2 Diabetes

Micronutrient insufficiency, low dietary fiber, and high saturated fat intake have been associated with chronic diseases. Micronutrient insufficiencies may exacerbate poor health outcomes for persons with type 2 diabetes and minority status. We examined dietary intakes using the Recommended Dietary Allowances (RDAs) of micronutrients, and Adequate Intakes (AIs) of fiber, and Dietary Guidelines for Americans (DGA) for saturated fat in Haitian-, African-, and Cuban- Americans (n = 868), approximately half of each group with type 2 diabetes. Insufficient intakes of vitamins D and E and calcium were found in over 40 % of the participants. Over 50 % of African- and Cuban- Americans consumed over 10 % of calories from saturated fat. Haitian-Americans were more likely to have insufficiencies in iron, B-vitamins, and vitamins D and E, and less likely to have inadequate intake of saturated fat as compared to Cuban-Americans. Vitamin D insufficiency was more likely for Haitian-Americans as compared to African- Americans. Diabetes status alone did not predict micronutrient insufficiencies; however, Haitian-Americans with no diabetes were more likely to be insufficient in calcium. Adjusting for age, gender, energy, smoking, physical activity, access to health care, and education negated the majority of micronutrient insufficiency differences by ethnicity. These findings suggest that policies are needed to ensure that low-cost, quality produce can be accessed regardless of neighborhood and socioeconomic status.