Tropical forests cover just 7% of total land but within them contain 50% of all plant, insect and animal species, making them one of the richest ecosystems on Earth . But they are disappearing fast. Storing roughly 25% of terrestrial carbon, tropical forests contribute significantly to climate change mitigation , so it is vital to reduce deforestation and maintain these vast carbon sinks. To tackle such a widespread issue, it is essential to address both the fundamental causes and the direct drivers of deforestation in the tropics. This article will focus on the broad underlying cause: unsustainable economic scale.
In economic terms, ‘scale’ refers to the physical size of the economy relative to the environment. Whilst the prevailing view is that the environment is being contained within the economy, most ecological economists argue that the economy exists within the environment, as there are physical limits and constraints on resource extraction and economic growth . More specifically, scale represents the ‘throughput’ or quantity of raw materials, i.e. timber and agricultural products, flowing from the environment, into the economy and then back to the environment in the form of waste . In the case of tropical deforestation, the scale of the economy has grown larger than the forest environment that contains it.
In most tropical regions, deforestation is being carried out on an unsustainable scale. Between 2000 and 2012, the tropical forest biome experienced the greatest forest cover loss of all forest types . An estimated 15% of tropical forest species have already become extinct due to deforestation and land use change . Deforestation accounts for roughly 20% of total anthropogenic carbon dioxide emissions . One study found that the tropical forest biome is the only environment in which deforestation rates are increasing annually . Tropical forest ecosystems cannot withstand this damage and will eventually collapse, leading to loss of profit and increased costs to the industries and economies that rely on them.
Contributing to this unsustainable scale of tropical deforestation are a host of complex drivers and activities occurring at various international, national and local levels. These can be generally separated into two categories: underlying drivers and direct drivers .
The underlying drivers are the result of the interactions between economic, political, social and technological factors that control the activities leading to deforestation and forest degradation. They include: the prices of forest and agricultural products which are determined by international markets; population growth; economic growth; national legislation as well as poverty and development issues. Two critical underlying drivers highlighted by the UN are: “...economic growth based on the export of primary commodities and an increasing demand for timber and agricultural products in a globalizing economy” . These pressures are projected to increase due to growing populations; global urbanisation; rises in meat consumption; economic growth and increasing GDP of developing countries .
Direct drivers are the activities that lead to forest clearance. Land-use change is the biggest cause of tropical deforestation . It is estimated that agriculture drives approximately 80% of deforestation worldwide . Forest is often burned to clear space for crop plantations such as soy and oil palm, or for grazing pasture for cattle. This practice completely disregards the true value of forests and the ecosystem services they provide, such as climate regulation, flood defence and as sources of food and medicine. Logging is the other major direct driver of tropical deforestation, contributing to roughly 70% of deforestation in South America and sub-tropical Asia . Both drivers must be targeted by policy to slow deforestation.
To ensure that the world’s tropical forests are not degraded beyond recovery, deforestation must be reduced to a sustainable scale. This could require the scale of the economy to decrease so that it remains within the limits of the tropical forest ecosystem. To achieve this, it is vital to decouple economic growth and deforestation in tropical countries . It is also crucial that rates of extraction be kept well below the rate at which forest naturally regenerates .
At the country level, improved forest management is necessary. Establishment of protected areas have been shown to reduce deforestation . Governments can utilize a combination of policy and market based approaches to reduce deforestation. Logging export bans and taxes can lower the market prices of timber. At the global level, a consumer boycott of cheap beef, soy products and processed foods containing palm oil could also disincentivize agricultural expansion in tropical forests.
Fundamental to achieving this reduction in scale is a shift in values and perception of the economy and natural resources. Policy makers must acknowledge that economic growth is limited by the finite environment and that growth by increasing the scale of the economy can create more costs than benefits due to environmental degradation . Trees have value when left in the ground: for mitigating future climate change as well as a source of materials and medicines for future generations.
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