[Coral-List] Low resilience of Caribbean coral reefs

[Vassil Zlatarski]

Dear all,

Kindly at collegial attention a very interesting concept and great topic
for our forum:

"A Vicious Circle? Altered Carbon and Nutrient Cycling May Explain the Low
Resilience of Caribbean Coral Reefs" by Joseph Pawlik, D. Burkenpile and R.
Thurber.. BioScience 2016.



*Abstract*
Coral reefs are economically important ecosystems that have suffered
unprecedented losses of corals in the recent past. Why have Caribbean reefs
in particular transitioned to coral-depleted systems and exhibited less
coral resilience? A synthesis of recent research from diverse sources
provides novel insights into the reciprocal interactions among sponges,
seaweeds, and microbes. We propose that coral loss resulted in more
abundant seaweeds that release dissolved organic carbon (DOC), which is
consumed by sponges. Sponges return carbon to the reef but also release
nutrients that further enhance seaweed growth. Both seaweeds and sponges
compete for space with the remaining corals, and the cycling of carbon and
nutrients alters microbial activity, with negative consequences for the
coral microbiome. Adding to these interactions are geographic factors that
enhance nutrients and DOC on Caribbean reefs, such as river discharge and
windblown dust. Relatively higher abundances of sponges and the absence of
phototrophic species suggest that sponge communities on Caribbean reefs
have adapted to a different nutritional environment than is present
elsewhere. This synthesis sheds new light on past hypotheses seeking to
explain the disparity in the recovery of coral reefs across the tropics,
provides new directions for research, and has implications for the
conservation of Caribbean coral reefs that are related to fisheries and
watershed management.

*PDF download available*:
https://www.researchgate.net/publication/301716649_A_Vicious
_Circle_Altered_Carbon_and_Nutrient_Cycling_May_Explain_
the_Low_Resilience_of_Caribbean_Coral_Reefs .
Cheers,

Vassil

Vassil Zlatarski
D.Sc. (Biology), Ph,D, (Geology)