Environmental Engineering Reference
In-Depth Information
Today the distribution of cold water corals appears to be limited to depths
above the saturation depth, suggesting that the deeper coral ecosystems
will eventually disappear (Guinotte et al. 2006).
Predicted rises in sea-level will probably have little effect on coral reefs
since they will merely provide more space for corals to grow upwards
without being exposed to the air. However, combined with an increase in
the frequency of tropical storms, sea level rises will hinder the development
of coral islands and atolls (Veron 2011).
Certain climate change impacts, particularly when combined with
other infl uences, are likely to reduce the overall resilience of coral reefs.
Changes in a coral community such as reduced biodiversity may severely
undermine system resilience, resulting in a phase shift to a non-coral reef
community. The loss of fi sh and invertebrates for instance may expose a
coral reef to outbreaks of pests or invading species. Such effects are usually
unpredictable but likely to increase (Wilkinson and Souter 2008).
The worldwide decline of coral reefs makes apparent the urgent
need to adopt appropriate management techniques based on a greater
understanding of the ecological processes that underlie reef resilience and
of the manner in which human activities contribute to shaping ecosystems.
Only in this way can we be better prepared for future changes (Bellwood
et al.
2004).
Effects of Climate Change on Rocky Intertidal Habitats
The intertidal zone constitutes the interface between marine and terrestrial
environments, where rocky shores are the most common littoral habitat on
open wave-exposed coasts (Thompson et al
.
2002). Determining factors for
the occurrence of the biota found on these shores are the ability to colonize
sites and tolerate a variety of stresses as well as smaller-scale physical
infl uences and interactions with other organisms (Lewis 1964, Connell
1972, Stephenson and Stephenson 1972, Little and Kitching 1996, Raffaelli
and Hawkins 1996). Rocky shores constitute an important functional link
with other inshore habitats and the land itself and provide feeding, resting,
spawning and nursery ambiences for a variety of mobile marine animals,
including fi shes and crustaceans, as well as birds, reptiles and mammals
(Thompson et al
.
2000).
Rocky shores are relatively simple ecosystems and the ecologies of
many of their species are well known, making them a good model system
for detecting changes in abundance, species distribution and biodiversity
(Hawkins et al
.
2003, Harley et al
.
2006, Helmuth et al
.
2006a), ultimately
furthering our knowledge of the consequences of climate change for
community and ecosystem processes (Hawkins et al
.
2008). Some of the
most profound and best-documented changes in accelerated warming of
