sustainable use of biological diversity.pdf - India Environment Portal

Sustainable use of biological diversity in socio-ecological production landscapes
have been attributed as the reason for high level of
faunal diversity in Kandyan homegardens. Twelve
mammal species belonging to five orders and seven
families have been recorded in Kandyan homegardens
in association with fruit trees (Hitinayake and
Ekanayake, 1999). A total of 35 birds belonging to
five orders and 14 families have also been observed
in Kandyan homegardens, including five endemic
species (Hitinayake and Ekanayake, 1999) whereas
Gunawardena (1998) recorded 53 bird species in
Kandyan homegardens, including eight endemic
species of which some species are rare. Twenty species
of butterflies belonging to four families have also
recorded in Kandyan homegardens by Hitinayake
and Ekanayake (1999) whereas 29 butterfly species
have been observed by Gunawardena (1998), including
endangered species. Thus, Kandyan homegardens
are considered as good sites for bird watching
and observation of butterflies.
3.4 Kandyan homegardens and environmental
conservation
The contribution of Kandyan homegardens to
sustainable management of land has been widely
studied, in particular to combat widespread land
degradation including soil erosion, soil structural
degradation and acidification. Kandyan homegardens
provide environmental conservation such as
protection of natural forests, increased multi-layered
vegetation cover leading to pleasant living environment,
erosion and pollution control and fertility
replenishment, in addition to food and nutritional
security and biodiversity conservation. Kandyan homegardens
also provide cultural identity since traditional
systems based on indigenous knowledge and
species are part of the cultural patterns of the community.
Further, it is generally suggested that trees
have a positive effect on the global carbon balance,
by means of carbon sequestration. The practice of
Kandyan homegardens are also helpful in preventing
figure 3. agroforestry raises tree cover to 50 per cent in this
landscape where natural forest cover is less than 10 per cent
© Pushpakumara
fires, as the lower vegetation, where fires usually take
place, is controlled in Kandyan homegardens.
In Sri Lanka, the contribution of homegardens to
the supply of timber and fuelwood to meet the domestic
and industrial needs has been well-recognized
(FSMP, 1995; Jacob and Alles, 1987; McConnell
and Dharmapala, 1973). Homegardens and
other forms of agro forestry systems supply over 50
per cent of national timber and 80 per cent of the
fuelwood needs. Since natural forestry will continue
to be allocated predominantly for the protection
of biodiversity and watersheds, agroforestry particularly
homegardens, rubber, coconut and forest
plantation will continue to be relied up on to supply
fuelwood and timber. The recent projections indicate
that non-forestland provides about 73 per cent
of the total sawlog demand of the country, of which
48 percent comes from homegardens (Gunathilake,
1974). Further, over 80 per cent of the total biomass
fuel demand of the country can be met by non-forestlands,
of which 38 percent are from homegardens.
Nearly 62 per cent of Kandyan homegarden owners
dependsolely on their homegardens for fuelwood
(Perera and Rajapaksha, 1991). Those examples suggest
that homegardens are the most important single
source of timber and fuelwood amongst the nonforestlands
(Gunathilake, 1994). Thus, Kandyan
homegardens prevent the forests from deforestation
by providing forest products. Among the underutilized
Kandyan homegardens, timber may be the
most promising commodity for the future.
Forest cover in Sri Lanka has declined from 70 per
cent at the beginning of the country to 44 percent
in 1956. Forty years later, 1997, the forest cover was
only 21 per cent (IUCN, 2007). Despite all efforts
both by the government and the non-governmental
organizations, deforestation continues to threaten
us. The present estimates indicate a further decline
up to 17 per cent in the year 2020 (FSMP, 1995). The
consequences of deforestations are serious and wellknown.
Natural forest cover in Kandy District is only about
17 per cent of the total land area, which is below the
national average (21 per cent). However, the vegetation
cover of the area excluding natural forests is
about 31 per cent due to the presence of well-connected
Kandyan homegardens. Thus, natural forests
together with homegardens provide almost 47 percent
of vegetation cover to the Kandy area, which is
a high value in terms of associated environmental
benefits of perennial crops in the area (figure 2).
Human health is directly linked to and dependent
on the state of health of the ecosystems that support
them. A wide range of economic and biographical
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