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on a large scale worldwide. The bog surface
is milled with rotating drums i xed with pins
that break up the peat. After drying, the
milled peat is picked up with a large vacuum
and placed in piles for further handling (Fig.
11-10B). The process may be repeated
several times each summer, and each year
drainage must be lowered to continue har-
vesting peat. In the end the peatland is
almost completely destroyed, although in
recent years attempts have been made to
restore cutover peatlands (e.g. Quinty and
Rochefort 2003).
peatlands and subsequent release of greenhouse
gases.
Another example of commercial extraction
comes from aquaculture production or the so-
called “blue revolution” (Simpson 2011). Aqua-
culture refers to the farming of aquatic organisms
such as i sh, mollusks, crustaceans and aquatic
plants from fresh, brackish, and marine waters.
Aquaculture is undertaken on a large scale in
many countries of the world and often involves
the conversion of coastal and inland wetlands
to i sh farms (Alongi 2002; Seto and Fragkias
2007). A recent Food and Agriculture Organiza-
tion report (FAO 2009) suggested that close to
44 percent of the seafood (including i sh, crus-
taceans and mollusks) consumed globally now
comes from aquaculture production. Aqua-
culture production has increased at a brisk 6.5
percent annually from approximately 28 million
tons in 1999 to 50 million tons in 2007 (Table
11-2).
Asia leads the world in aquaculture
production
-
supplying a staggering 88 percent
of global demand. As Table 11-3 indicates, in
2007 China alone contributed over 60 percent
of the world's aquaculture at 31 million tons,
with India (3.4 million tons) and Vietnam (2.2
million tons) trailing a distant second and third.
Several factors explain China's large market
share in aquaculture. The country has a long
history of aquaculture production dating back
several millennia. Since the 1950s the Chinese
government has provided many incentives for
aquaculture production and invested large
research funding into developing more efi cient
techniques (Guo 2000). These factors, coupled
with the widespread traditional practice of
Examples of large-scale commercial extractive
activities using wetland ecosystems are often
scrutinized closely due to their more visible
impacts. Global market forces and local govern-
ment policies promoting export-led growth and
responding to local development pressures
often drive such undertakings. The recently
established oil-palm industry of Kalimantan,
Indonesia provides one such example (Wood
and van Halsema 2008). Beginning in the mid-
1990s, in response to the global demand for
biofuels, the peat-swamp forests of central Kali-
mantan were cleared and burned to make way
for oil-palm plantations. With international
investment, oil-palm production rose from 5
million tons in 1995 to 18 million tons by 2008,
generating important export revenue for Indo-
nesia (U.S. Department of Agriculture 2007,
2010c). This conversion of wide swaths of Indo-
nesia's peatlands to oil-palm resulted in signii -
cant releases of CO
2
(Wood and van Halsema
2008). Ironically, the call for greener biofuels
has inadvertently led to the destruction of
Table 11-2.
Aquaculture production for i sh, crustaceans and mollusks by region. Source: Food and Agriculture
Organization. 2009.
Yearbook of Fishery Statistics 2007
. Accessed online
<
ftp://ftp.fao.org/docrep/fao/012/i1013t/
i1013t.pdf
>
October 2010.
Region
1998 (tons)
1998 (%)
2002 (tons)
2002 (%)
2007 (tons)
2007 (%)
World
28,412,656
100
36,781,779
100
50,329,007
100
Africa
186,362
0.7
453,638
1.2
824,762
1.6
Americas
1,261,893
4.4
1,799,643
4.9
2,430,546
4.8
Asia
24,922,366
87.7
32,358,284
88.0
44,565,579
88.6
Europe
1,921,404
6.8
2,042,398
5.6
2,339,515
4.7
Oceania
120,631
0.4
127,816
0.4
168,605
0.3
