Geography Reference
In-Depth Information
(Kondrashin 1991). Walsh
et al
. (1993) review the
relationship between deforestation and several
other vector-borne diseases apart from malaria,
including the arboviruses; Chagas' disease,
leishmaniasis, loiasis, lymphatic filariasis,
onchocerciasis, and schistosomiasis.
remains clear. Deforestation is a byproduct of
development. Deforestation's foot soldiers may be
the rural poor who, lured by promises of
economic gain or driven by scarcity, clear more
and more forest land. Their lieutenants may be
national administrations eager to expand their
national economies and win foreign exchange.
However, neither the rural poor nor their
struggling national governments are capable of
preventing deforestation. As the World Bank
analysts prove, their economic best interests usually
lie elsewhere (Chomitz and Kumari 1996).
Deforestation might be halted by concerted
international action although, at present, despite
the noise of the environmentalists, the political
will needed to effect change simply does not exist.
However, international action cannot halt the
most important cause of deforestation. The
developing world must develop. Deforestation is
the hallmark of human civilisation. It marks the
conversion of a traditional economy to a modern
agricultural and urban economy. It has affected
everywhere that civilised society has taken root.
The main factor that divides the progress of
deforestation in the developing world from that
in the developed world is that, in the latter,
deforestation has already taken place.
Certainly, deforestation is also an agency of
environmental degradation, and it can be the
nemesis of development. On the loess plateau of
China, deforestation converted an economically
and culturally advanced society into an
impoverished and backward one (Fang and Xie
1994). Similar tales are told for places as diverse as
North Africa, Central America and Easter Island.
However, deforestation continues, and will
continue, because it is in the immediate rational
self-interest of those who destroy forests to do so.
Preventing deforestation will require a major
change in cultural values, social attitudes and, most
especially, the economic rules of play. This is
possible. In northern Europe and China, the rate
of forest increase exceeds extraction, albeit for
different reasons. Meanwhile, the developed world
conspires towards the deforestation of the
underdeveloped. It still deploys more economic
muscle in favour of those who deforest than
REFORESTATION
A huge volume of work is published on the
problems and processes of forest reconstruction
(Lamb
et al
. 1995). The environmental impacts of
reforestation are not the reverse of those due to
deforestation. Many of the impacts of deforestation
occur because of the loss of the forest soil and litter
layers. New forests mine the environment for
nutrients. They accelerate weathering and fracture
rocks for anchorage. New forests may have very
different environmental contexts from the forests
they replace. Schreier
et al
. (1998) had to resort to
GIS modelling to deconstruct Nepal's record in
afforestation. Among other things, in Nepal, new
plantations tend to be located on relatively gentle
slopes, while deforested areas are more often on
erodible steep lands
(ibid.).
In fact, the results from
research into the impacts of reforestation are full of
surprises. Awaiting publication are findings showing
that on steep grazed pastures, there is a positive
correlation between trees and erosion, because
animals congregate beneath trees, and trees planted
on steep banks may reduce erosion by three-
quarters, even in the absence of forest soil and litter
layers. Finally, results from Japan demonstrate that
reforestation in mountains can lead to long-term
increases in streamflow, despite the increased losses
to evapotranspiration— perhaps due to rain
harvesting or more likely due to changes in deep
seepage to groundwater (Shibano 1998).
CONCLUSION
The causes of deforestation are complex. The
research literature is gigantic, complex,
multidisciplinary, scattered and often-hard to
evaluate. However, the main cause of deforestation
