Thesis Master of Science University of Washington 2013

List of Figures.. List of Tables.. Preface.. Chapter I. Forest Community Changes Resulting From Firewood Harvest in the Highlands of Chiapas, Mexico.. 1. Introduction.. 2. Methods.. 2.1 Study area.. 2.2 Analysis.. 3. Results.. 3.1 Tree species and species class.. 3.2 Tree community variation among zones.. 3.3 Environmental characteristics affecting plots across management zones.. 3.4 Regeneration.. 4. Discussion.. 4.1 Characteristics of firewood extraction zones.. 4.2 The degradation process.. 4.3 Restoration.. 5. Conclusions.. Chapter II: Firewood Use in a Community-Managed Forest in the Chiapas Highlands.. 1. Introduction.. 1.2 Firewood use by communities in Mexico.. 1.3 Induced pine forests.. 1.4 Potential for regeneration.. 1.5 Study purpose.. 2. Methods.. 2.1 Learning about local perceptions of the forest.. 2.2 Assessing current forest composition.. 3. Results.. 3.1 Perceived value of Lázaro Cárdenas' forest.. 3.2 Formal and informal community forest management.. 3.3 How much firewood the community uses.. 3.4 Current forest composition.. 3.5 Observed changes in the ejido's forest.. 4. Discussion.. 4.1 Impact of firewood harvest on the forest community.. 4.2 Impact of existing forest management on the forest community.. 4.3 Management reforms to ensure stability of the pine oak forest.. 4.4 Limitations.. 5. Conclusion.. Points for Further Research.. Acknowledgments.. References.. Appendix 1. Tree species documented in data collection.. Appendix 2. Relationships between biomass, regeneration and stump presence by zone.. Appenidx 3. Indicator Species Analysis.. Appendix 4. Relationships among regeneration communities.. Appendix 5. Interview guide.. Interview Guide: Women and Men in Household.. Interview guide: chainsaw operator

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I examined the impact of firewood extraction on the degradation of an oak-pine forest in the highlands of Chiapas, Mexico. The study site, Lázaro Cárdenas, is a 1702 ha community-man-aged forest (i.e. ejido) supporting 1177 indigenous Tzotzil people. The ejido owns and actively manages the land including: milpa agriculture, grazing livestock, collecting non-timber forest products for ceremonial and medicinal uses, extracting pine lumber, and collecting firewood for cooking and heating. I collected forest vegetation data at 24 plots in the ejido spanning a range of degradation. I also used semi-structured interviews of 16 households to assess firewood use and perceptions of forest change. Firewood extraction causes forest degradation with heavily used sites showing lower biomass of oaks, lower forest cover, lower species diversity, and higher pine establishment than in sites where firewood is not extracted. Interviews documented people's preference for burning oak, and interviewees noted a decline and access to oak for fire-wood. The average firewood use calculated from interviews is 2.45 kg person-1 day-1, while cal-culations from direct measurement of woodpiles suggests an average of 10.5 kg person-1 day-1; a total of 831 MgC is removed each year. The results suggest that preferential selection of oak for firewood over pine is an early cause of induced pine dominance, pinarización, in the Chiapas highlands. Inglés

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