Geoscience Reference
In-Depth Information
sinkinG ColoMbian shores
Mangroves are the warm-water equivalent of salt marshes. Along the Pacific Coast of Colombia they form a continu-
ous swamp-forest from the mainland to the oceanfront of barrier islands. Before the 1990s these barrier islands were
not recognized as such, because the dense forest concealed the lagoon behind the islands.
be able to successfully keep up with the ex-
pected sea level rise by migration into shal-
lower water or upward growth.
Yet the likelihood of reef survival is
greatly reduced by the stress caused by hu-
mans. The array of hazards, both man-
made and natural, threatening coral reefs
is seemingly endless. The increased carbon
in the atmosphere is causing ocean acidifi-
cation, which is probably weakening coral
skeletons and making calcification difficult
for juvenile corals. If temperatures rise too
quickly, the result can be bleaching caused
by the loss of oxygen-producing zooxan-
thellae algae, and death for many corals
and their associated organisms. Humans
drive ships that crash into reefs, dredge
channels through them, drag anchors over
them, spill oil on them, cover them with
beach sand, mine them for building blocks,
pollute the waters, and collect coral heads
for mantelpieces. The loss of the offshore
