Environmental Engineering Reference
In-Depth Information
Some 85 million ha may be suitable for natural regeneration, farm forestry and SRWCs, but only
20 million ha could be planted by 2030 (Piketty et al. 2008). Other estimates of potential SRWC
extent included 30 and 41.2 million ha. Brazilian states with available grasslands and savannas for
SRWC planting include Mato Grosso, Maranhao, Tocantins, Piaui, Goias, Para, Minas Gerais, Mato
Grosso do Sul, and Bahia, with Piaui preeminent for sustainable
Eucalyptus
SRWCs involving
small and medium landowners.
Brazil has very favorable land, climate, policies, and experience in highly productive SWRCs for
the pulp and paper industry and increasingly for bioenergy. Given the prominence of current and
future
Eucalyptus
SRWCs (Table 15.1) in areas with large energy needs and production potential,
Eucalyptus
can be a significant contributor of a range of energy products.
Eucalyptus
wood is even
used for making activated carbon adsorbents for liquid-phase applications such as water and waste-
water treatment. In the tropics and subtropics where
Eucalyptus
species are already widely planted,
their further deployment for energy products is especially likely.
15.2.1.2 china
In 2002, China's 7.5 EJ of bioenergy consumption (16.5% of total energy), including approximately
200 million tons of firewood, more than doubled that of any other country and is increasing (Wright
2006). In 2000, China led the world in afforestation. Plantations totaled 4.67 million ha in 2002,
though only a portion was likely SRWCs for energy. In 2006, SRWCs were up to 10 million ha,
mostly in southern China. Goals for 2010 and 2015 were some 13.5 million ha of ''fast growing
plantations.” China's 24 million ha of new plantations and natural regrowth transformed a century
of net carbon emissions by forestry to net gains of 0.19 Pg C per year, offsetting 21% of its fossil fuel
emissions in 2000 (Canadell and Raupach 2008).
Commercial biomass energy is only about 14% of the total energy consumed in China (Wright
2006). China has very abundant but inefficiently used bioenergy resources. Bioenergy is mainly
used in rural areas, accounting for 70% of rural energy consumption. Started in 1981, firewood
plantations totaled 4.95 million ha by 1995 and provided 20-25 million tons of firewood each year
that largely alleviated the rural energy crisis. Now, 210 million m
3
of firewood are produced annu-
ally, equivalent to 120 million tons of standard coal.
China's forest area of 175 million ha in 2003 contained a forest volume of approximately 12 bil-
lion m
3
. Plantations were approximately 53 million ha with a volume of 1.5 billion m
3
. Still, China
faced a deficiency of industrial timber, as industrial roundwood consumption in 2004 was 310 mil-
lion m
3
and was expected to reach 472 million m
3
in 2020. Fast-growing, high-yielding trees for
industrial plantations are needed to ease the deficiency.
Eucalyptus
species are very important for industrial plantations in China (Xiong 2007). China
now has the second largest
Eucalyptus
plantation in the world, just behind Brazil. First introduced
into China in 1890 as ornamental and landscape trees, 70 species have been successful, and over
1.8 million ha of
Eucalyptus
are established in the Southeast. More than 20 years of selection and
breeding in collaboration with Australian researchers resulted in 135 seed sources and more than
600 clones for Guangxi province. Through tests, approximately 2000 elite trees in 500 families
were selected for the first breeding populations of 10 species including
EU
,
E. tereticornis
,
EG
,
EU
×
EG, E. pellita
,
E. camaldulensis,
and
E. dunnii
. Genetic gains of 15-25% were realized
after the first generation. By crossing 12 species, good hybrids were selected, with the best fami-
lies and clones growing substantially better. Cold hardy crosses such as
EU
×
E. camaldulen-
sis
and
E. tereticornis
have also been created. Concurrent with a broad research program, seed
orchards and clonal gardens were created for selected species. The biggest propagation center
is in Guangxi, which provides superior seed or vegetative propagules for southern
Eucalyptus
plantations.
In China, eucalypt plantations are harvested for pulpwood, fiberboard, sawlogs, roundwood,
veneer, fuelwood and oil. Residues and leaf litter are used for fuelwood. Eucalypt oil production is
primarily confined to cooler, temperate regions, where up to 150,000 ha of plantations are used for oil.
