Task 113

Does Management Matter? Assessing the Effects of Charcoal Production and Management on Woodland Regeneration in Senegal

Principal Investigator(s):

K. Wurster

Sponsor(s):

M. Imhoff

Last Updated:

October 26, 2012 15:25:23

Description of Problem

In much of Sub-Saharan Africa, more than 75% of a rapidly growing urban population depends on charcoal as their primary source of energy for cooking. The high demand for charcoal has led many to believe that charcoal harvesting catalyzes widespread deforestation. The Senegalese government and international donors have initiated projects within protected areas to combat deforestation and created land management plans to sustainably harvest charcoal. To date, the effects of forest management techniques on forest sustainability are still in question. This research uses a multiphase approach integrating satellite analysis with field surveys to assess the effect of varying forest management strategies on forest regeneration and sustainability after charcoal harvesting.

Scientific Objectives and Approach

This research uses a combination of remote sensing, forestry surveys and semi-structured interviews to assess the effects of land management practices on forest regeneration and species composition around charcoal production areas from 2000 to 2008. The study also tests MISR’s ability to effectively detect vegetative structural change. To accomplish this, the following set of questions and hypotheses are addressed:

Can the MISR derived k (red) parameter detect changes in vegetative structure?

Do regeneration rates around charcoal production areas differ depending on land management type (locally managed commons vs. classified forest vs. co-managed forest)?

H1: Holding cover type constant, land management type will result in no significant variation in regeneration rates near charcoal production sites from 2000 to 2008.

How does charcoal production affect forest structure, biomass, and species composition?

H2: Controlling for cover type; forest structure, biomass levels, and tree species composition and richness will be less in areas of charcoal production when compared to areas of no production.

What are the factors that influence regeneration rates after charcoal production?

H3: Controlling for cover type; regeneration rates, species composition and richness, biomass levels and forest structure are negatively correlated with proximity to agricultural plots, grazing land, villages, and major roads.

Accomplishments

Field data for the Tambacounda study region of Senegal was collected from January to May of 2008. Plot and species characteristics were collected over 77 sites and recorded for over 2400 individual tree species across the four land management types. Preliminary analysis of the field data concludes that harvested and non-harvested sites are significantly different (P<0.001) when comparing species diversity indices, average diameter at breast height, and average tree height. There is little significant difference between land management types. Moreover, when the area is analyzed for long-term ecological resilience using size class distribution curves, all land management types are lacking in the proper distribution of seedlings/saplings to mature individuals to maintain a diverse woodland environment.

Field data from 2003 and 2008 were then used to validate the MISR derived k (red) parameter. All MISR scenes have been collected, processed, and analyzed from 2000 to 2008. Results indicate that the MISR derived k(red) parameter can successfully differentiate between bare, woodland, and forested land types (Wurster 2009 in press), but is not consistently detecting subtle changes in vegetation structure resulting from harvesting of the woodland land cover type for charcoal production. Future analysis of the MISR time series will further address how well the k (red) parameter can detect changes around sites harvested for charcoal production.

This research was completed in April 2010 with the completion of my Ph.D. from the University of Maryland, Department of Geography. The final dissertation title was “Management Matter? Effects of Charcoal Production Management on Woodland Regeneration in Senegal.”

Refereed Journal Publications

Wurster, K., 2009: Testing the Capability of MISR in Detecting Forest Changes Caused by Charcoal Production in Senegal. International Journal of Remote Sensing, 30(19), 5151-5157.

Other Publications and Conferences

Wurster, K. 2010: Analyzing the Impact of Charcoal Harvest and Land Management Type on Vegetation Regeneration in the Tambacounda Region of Senegal. BioEcon Conference, Venice, Italy, Sept 22, 2010.

Wurster, K. 2008: Using MISR to Monitor the Effects of Charcoal Production on Forest Structure and Regeneration in Senegal. MISR Conference, Pasadena, CA, Dec 12, 2008.

Wurster, Karl 2007: Multi-angle Imaging SpectroRadiometer (MISR) detection of charcoal production sites in Senegal. Conference Proceedings – ForestSat 2007, Montepelier, France, November 5-7, 2007.