Agriculture threatens nearby protected forests
The expansion of agricultural land and range land – covering nearly half of the earth’s surface – has a dynamic spill over effect across the boundaries where protected cultivated land meets natural land which has spurred concern amongst ecologists and environmentalists.
This is because cultivated areas influence the natural ecosystems through abiotic (physical) edge effects and also indirectly by modifying interactions between species.
Of most concern to ecologists is that in this interaction across the boundaries some species will thrive will others will suffer tipping the careful balance of our natural ecosystems.
According to this study, the wild boar numbers grew a hundred-fold in forests adjacent oil palm plantations, even when the forests and plantations were one kilometre apart.
Researchers document the case of oil palm plantations situated in the tropical lowland landscape of Southeast Asia and the ecological impact of agriculture which increases the population of crop-raiding wild boars which subsequently affects the native vegetation of distant protected forest areas.
The researchers examined wild boar reproduction and forest tree dynamics for twenty years in a 130 km2 forest reserve in Malaysia which was surrounded by palm oil plantations.
The fallen fruits from oil palm attracts native wild boars providing them a rich source of food, which then helps them multiply their numbers while damaging forest trees and preventing them from regeneration.
According to this study, the wild boar numbers grew a hundred-fold in forest adjacent oil palm plantations, even when the forests and plantations were one kilometre apart.
The wild boars reduce the number of trees and saplings in forests compared to the experimental fenced-in areas of the forests which did not have wild boars.
This damage is mainly due to pregnant wild boars harvesting small trees to build nests for their young ones, leading to the disappearance of plants and trees from the forest floor.
This study demonstrates that the effects of agriculture is not restricted to cultivated land but has a resonating effect on nearby uncultivated areas.
The researchers have also noticed a surge in the population of pigs and macaque monkeys in forests near oil palm plantations in Peninsular Malaysia, Borneo, and Sumatra.
These other animals along with macaque monkeys forage on oil palm fruit, thus increasing their population in nearby forest areas. These animals then eat birds’ eggs and a variety of species altering the food webs in forests near oil palm plantations.
Many of the world’s tropical forests lie within a kilometre of non-forested areas and researchers suggest that having a larger buffer area between the two may limit wildlife access to agriculture land.
Researchers urge oil palm growers as well as regulatory bodies and countries to find ways limit the negative impacts caused by plantations as shown by this study which researchers hope provides insight to policy makers globally to better protect our environment and our forests.
Source: Nature Communications