Chapter 16 Case Study: Can Agroforestry Serve Economics and Ecology? Capturing Carbon with Crops
Han de Groot of the Rainforest Alliance writes for Scientific American that trees are our best technology to use against global warming. Sometimes nature gives us all we need. The alarm over global climate change is being sounded now louder than ever. The IPCC warns that effects from global warming of 2° Celsius could be catastrophic. Policymakers typically emphasize solutions such as reducing carbon emissions or even expensive machinery that captures carbon from the atmosphere. De Groot argues that forests are actually the most efficient “carbon-capture technology” we have. In fact, this method of carbon capture could be responsible for achieving 37% of the climate target—massive results could be achieved by a natural solution as simple as reforesting. A single tree can store 48 pounds of carbon in a year, and large forests can store the equivalent of the emissions of entire countries—Columbia is given as an example. What stops us from reforesting? Not surprisingly, it is often economics.
Rather than replanting forests and so that they will grow and recapture carbon, we are seeing forests cut down, often for agricultural purposes. Many of the crops are specialty commodities (e.g., cocoa trees) that end up competing with the world’s great forests for space. Yet, de Groot argues that maintaining forests so that they can capture carbon need not represent an economic disaster—ecological and economic interests can both be accommodated: “It is estimated that increased investment in the multi-strata agroforestry area could help sequester up to 9.28 gigatons of carbon dioxide, while saving a net $709.8 billion by 2050. In production landscapes where large-scale tree cover increases are difficult, agroforestry serves as an attractive compromise.”
Agroforestry produces crops but using a blend of different trees mixed together, each representing a different layer of the forest. For example, tall trees like macadamia can be grown with coffee and cacao in the shade. While producing crops with economic value, an acre of agroforest sequesters approximately 2.8 tons of carbon a year. In addition to carbon capture, it also protects the land from water erosion, restores groundwater, restores soil, and supports biodiversity.
De Groot points to success stories such as community-managed forests in Guatemala which have seen a zero percent deforestation rate over more than a decade. He directs our attention to the Bonn Challenge adopted by 56 countries, which has the goal of restoring 150 million hectares of natural landscape by 2020 and 350 million by 2030. This is given as an example by de Groot of both an ecological and economic gain:
Landscape restoration promises an unparalleled return on investment, in terms of ecosystem services and carbon sequestered and stored. Landscape restoration could potentially sequester up to 1.7 gigatons of carbon dioxide every year, according to the International Union for Conservation of Nature. Reforestation projects can also intersect neatly and positively with human systems—restored forests provide a renewed resource base and new economic opportunities for communities.
Which sort of sustainability does de Groot’s proposal for reforestation using investment in agroforestry best exemplify? Broad, weak, narrow? How does his approach to sustainability view the relationship between the value of nature and economic goods? Are they commensurable?
Case study by Robert Reed