Science Wednesday: Sustaining Tropical Forests

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The Amazon basin contains more than half the world’s remaining tropical rainforest, and is facing unprecedented changes that will have major impacts on biodiversity, regional hydrology and the global carbon cycle.

But the need for employment is causing tropical deforestation on a vast scale.

Stopping deforestation requires forest management strategies that provide jobs for people living in or near forests while also creating incentives for forest conservation. The andiroba tree (C. guianensis)– valued for the high-quality oil extracted from its seeds and for its mahogany-like timber—could provide this opportunity.

Collect the seeds, cut down the tree, or a little of both?

image of author standing on a root of a big tree over waterThrough my research, I am looking at the intersection of conservation and economics related to harvesting C. guianensis. I am using ecological models with an economic component to answer the question: Under what ecological and market conditions would the collection of C. guianensis seed oil be favored and, conversely, under what ecological and market conditions would C. guianensis timber harvest be favored?

Since 2004, I have been measuring growth, survival and reproduction of C. guianensis trees at my research site in the Brazilian Agricultural Research Institute’s 1,200-hectare research forest in Acre, Brazil.

Using these measurements, I plan to fine-tune models about future tree growth under various management scenarios, as well as identify how different life stages, such as seedlings, saplings, mature trees, etc., contribute to growth of the entire tree population. For example, it is possible that leaving a certain number of reproducing trees per hectare would maintain a growing population, leaving other, non-reproductive trees to be harvested?

I will use the new model to determine sustainable harvest limits for both timber and seed, and then incorporate the results into a financial assessment of these two competing strategies to manage the species. To ensure that the tree population is maintained and that it generates income, I plan to compare the relative compatibility of timber vs. seed harvest.

After I finish writing up my results, I will return to Brazil to give a series of training workshops and seminars on my results so they can be applied to forest management practices. In addition, I will compile materials (including comic-book-like illustrated pamphlets) that break down my results into tools that can benefit forest residents and local nongovernmental organizations. By sharing my research results in this way, I hope that I can provide important information to the local Brazilian government and play a part in helping people living near the forest find a sustainable way to create income based on a standing (or managed) forest.

About the author: Christie Klimas is a PhD student at the University of Florida in the department of Forest Resources and Conservation. A 2004-2006 EPA Science to Achieve Results (STAR) Graduate Research Fellowship supported her Master’s Degree research.

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