Tree plantations may not improve forest cover, livelihood benefits: Study
NEW DELHI: A new research paper has found that large scale tree plantations may not improve forest cover or provide livelihood benefits to local people. The paper is based on a study that found that large scale plantations in Himachal Pradesh’s Kangra 1965 onwards have not increased the proportion of forest canopy cover and actually shifted tree composition from broad leafed varieties used by local people for fodder and firewood to needle leaf species which are not as useful .
The study was conducted by a team that included researchers from Florida State University, University of Chicago, and the Centre for Ecology Development and Research, Dehradun. The researchers used satellite imagery to study two aspects of the plantations—forest canopy cover and forest composition.
The paper published on September 13 in Nature Sustainability suggests that the percentage of each plantation area classified as having more than 40% tree canopy density did not increase after establishment of plantations. Tree canopy density did not improve even after trees that were planted matured, say, 20 years of establishment. In terms of tree composition, the satellite data indicated 10% less broadleaf cover.
In 2015, the extent of global tree cover from planted forests was estimated at 280 million hectares, of which 12 million hectares was in India according to the paper. Many countries have begun adopting large-scale tree planting programmes because of the potential of forests to absorb carbon and support local livelihoods. For example, India’s nationally determined contributions (NDC) under the Paris Agreement has an element hinging on largescale tree plantations that will create an additional carbon sink of 2.5 to 3 billion tonnes of CO2 equivalent through additional forest and tree cover by 2030.
“Understanding the impact of such policies (tree plantation) is critical to understanding whether broader goals of forest restoration will be met. Planting trees may seem like a simple activity. Yet, in practice, tree planting may conflict with existing land uses, particularly in densely settled agrarian landscapes, generating challenges for low-level forest officers charged with implementing activities on the ground, in pursuit of the ambitious targets established at higher levels of government,” the paper said. Household livelihood surveys carried out by the team showed that tree planting supports little direct use by local people because of the nature of species planted.
“India has attempted large scale forest restoration for decades. We have just published one of the first systematic evaluations of these efforts. We find that decades of tree planting have had almost no impact on forest canopy cover or rural livelihoods,” tweeted Forrest Fleischman, associate professor of environmental and natural resource policy at University of Minnesota, one of the co-authors of the study. “On average, there was no change in canopy cover after plantations -- even decades after (when we would expect the planted trees to be fully grown -- and thus adding to the canopy cover). So, at the most basic level, planting trees didn’t accomplish an increase in forest cover.” The paper concluded that large-scale tree planting may sometimes fail to achieve both climate mitigation and livelihood goals.
“I cannot comment on the paper without going through it properly but plantations do sequester carbon and mitigate climate change. Trees convert carbon into biomass. Of course, in a dense natural forest the soil carbon is higher because of humus and other organic matter. Canopy density can be as high as 100% in some plantations. It depends on the species and nature of plantations,” said Siddhanta Das, former director general of forests.
A senior official from the forest conservation division of the environment ministry declined to comment on the paper.
“India has had a vexed history of government led afforestation programmes since the 1970s, that has been critiqued for not just its ecological blindness and displacement of community rights but also for reinstating social hierarchies. The push for plantations has also generated a policy legitimacy for practices such as compensatory afforestation which have allowed governments to justify the loss of biodiverse forest areas, important for wildlife and intrinsically linked with thriving local economies,” said Kanchi Kohli, legal researcher, Centre for Policy Research.