Publicaciones

@article{Díaz-Ortega2014,

title = {Unsustainable Land-Based Source Pollution in a Climate of Change: A Roadblock to the Conservation and Recovery of Elkhorn Coral Acropora palmata (Lamarck 1816)},

author = {Geraldine Díaz-Ortega and Edwin A. Hernández-Delgado},

url = {https://www.sampr.org/sam/wp-content/uploads/2015/02/Diaz-Ortega-and-Hernandez-Delgado-2014.pdf},

year  = {2014},

date = {2014-07-18},

journal = {Natural Resources},

volume = { 5},

pages = {561-581},

abstract = {Chronic eutrophication and turbidity are critical detrimental factors impacting coral reef ecosystems,

adversely affecting their ecological functions, services, benefits, and resilience across multiple

spatial scales and over prolonged periods of time. Inadequate land use practices and lack of

appropriate sewage treatment can adversely contribute to increase land-based source pollution

(LBSP) impacts in coastal waters and to magnify impacts by sea surface warming trends associated

to climate change. Fringing coral reefs off Vega Baja, Puerto Rico, support extensive remnant

patches of Elkhorn coral Acropora palmata (Lamarck 1816), which was listed in 2006 as a threatened

species under the US Endangered Species Act. Chronic impacts by LBSP have significantly affected

local downstream fringing reefs. We characterized the spatial extent of a water quality

stress gradient across 12 reefs along the Vega Baja coast through monthly measurements of multiple

physico-chemical parameters. Most parameters, particularly PO4, + NH4 , chlorophyll-a, and

the concentration of optical brighteners (OABs), showed a statistically significant increase

(PERMANOVA, p < 0.05) in waters close to the main pollution sources, but also in waters adjacent

to Cibuco River effluents. Dissolved oxygen also declined and turbidity increased on polluted sites.

PO4, + NH4 , and chlorophyll-a, exceeded recommended concentrations for coral reef ecosystems by factors of 7 - 50 times, 600 - 1240 times, and 17 - 83 times, respectively, depending on the source

of the effluents and the distance from sewage pollution sources. Also, water turbidity exceeded 4 -

10 times the recommended value for pristine coral reefs. Coral reefs showed significant decline in

close proximity to the polluted zone, showing a significantly different benthic community structure

(PERMANOVA, p < 0.0001) dominated by non-reef building taxa (i.e., macroalgae, algal turf)

and bare substrate. Percent coral cover and abundance of A. palmata, showed a significant increase

with distance. Coral species richness, species diversity index, and the variance in taxonomic

distinctness were very low on reef patches adjacent to the polluted zone, increased at a moderate

distance with increasing coral cover and co-existence of multiple species, and declined far

from the pollution source due to dominance exerted by A. palmata. This study suggests that

chronic LBSP resulted in a major decline of one of the largest and most dense remnant stands of A.

palmata across the northeastern Caribbean and that nutrient and chlorophyll-a concentrations

were unsustainable for coral reefs. This situation requires immediate solution to prevent further

damage to these unprecedented resources. It further suggests that chronic LBSP may synergistically

magnify sea-surface warming impacts driving corals to an increased state of risk in face of

forecasted climate change impacts. Actions to mitigate and adapt to climate change impacts on

coral reefs must require a priori controls of LBSP to be effective.},

keywords = {Acropora palmata, Coral Reef Decline, Eutrophication, Land-Based Source Pollution},

pubstate = {published},

tppubtype = {article}

}