climate change on UAE - Stockholm Environment Institute-US Center

8. Biodiversity,
ecosystem thresholds,
and <strong>climate</strong> <strong>change</strong>
There are a wide range of drivers which may
<strong>change</strong> ecosystem structure and function,
including human influences such as land use
and pollution, shifts in <strong>climate</strong> patterns, and
alterations to physical or chemical balances.
One key element of ecosystem health is its
biodiversity, a metric of how many different
distinct types of flora and fauna interact in the
same space. An ecosystem with high biodiversity
is highly resilient to damage and disturbance,
and is able to resist <strong>change</strong>.
Losses in biodiversity leave key ecological
niches unfilled, and may promote instability
or catastrophic <strong>change</strong> in an ecosystem. Like
a well-balanced portfolio, a highly biodiverse
ecosystem is less likely to collapse or be adversely
affected by disturbances over long periods (such
as shifts in <strong>climate</strong>) or short periods (such as
wildfires, pathogen or disease outbreaks, or
flooding); each element of the ecosystem is
susceptible to some type of damage, but resilient
to other forms – as a whole, an ecosystem with
high biodiversity can function well even in the
face of adverse conditions. As we look to assess
the potential impact of <strong>climate</strong> <strong>change</strong> on the
UAE, biodiversity and ecosystem function will
remain a key concept.
It is important then, to understand not only the
role of biodiversity on ecosystem function, but
the role of anthropogenic (human) and <strong>climate</strong>
<strong>change</strong> on biodiversity. Generally speaking,
researchers agree that the last two centuries
have seen an extraordinary loss of biodiversity
(Ceballose and Erlich, 2002; Hughes, 1997),
rivaling (if not exceeding) the extinction rates
of geologic historic mass extinctions (Balmford,
2003). Researchers have attributed much of this
biodiversity loss to:
over-harvesting of both predator and prey
species (e.g. overfishing and hunting);
habitat destruction (e.g. deforestation,
overgrazing, or pollution); and
<strong>climate</strong> <strong>change</strong>.
Over-harvesting of species can lead to critical
shortages in breeding populations, meaning
that a population is not large enough to re-
Impacts, Vulnerability & Adaptation for
Dryland Ecosystems in Abu Dhabi
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