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Yale Tropical Resources Institute
Dr. Michael Dove, Director
Nathaniel Delafield, Program Director
School of Forestry & Environmental Studies
210 Prospect Street
New Haven, CT 06511
U.S.A.
phone 203.432.3660
fax 203.436.4404
www.yale.edu/tri
©2006 by Yale Tropical Resources Institute
Web construction by MetaGlyfix
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TRI Fellows Research Projects, 2004
 North America
 Sharifa Gulamhussein, MFS 2005
Leaf Adaptations of Acacia koa (Gray) to moisture across varying elevation and substrate age gradients in Hawaii, USA.
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Sharifa hanging out with Pele, Hawaiian volcano goddess at the Thomas A. Jaggar Museum, Hawaii Volcanoes National Park.
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Location: North America, Hawaii
One environmentally-friendly approach to reforesting degraded tropical lands involves planting native tree species. Acacia koa (Gray), commonly referred to as ?koa,? is a native Hawaiian hardwood with immense potential for reforesting Hawaii's montane forests. In order to make informed and successful koa reforestation decisions, it is essential to understand how koa trees respond physiologically to limiting factors such as moisture availability in the field.
I'm interested in finding out what environmental conditions are optimal for koa growth, and in particular, how water and drought stressed conditions affect koa tree physiology. Water can be one of the most influential plant limiting factors in the wild, significantly affecting tree health and forest structure and productivity. By examining phyllode (pseudo-leaf) anatomical characteristics in tandem with carbon 13 isotope analyses, we can gain insight into how koa trees adapt and respond to drought-stressed soil conditions along various environmental gradients.
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Analysing Koa phyllode physiology at the histology lab in the Komohana Agricultural Complex — Hilo, Hawaii
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Ultimately, quantifying water-use of koa trees across varying environmental conditions is imperative for making informed conservation and forest management decisions in Hawaii. My study asked: what is the water-use efficiency of koa trees across different altitudinal and substrate gradients, and how does phyllode morphology & physiology differ across these gradients?I conducted my TRI summer research project on the big island of Hawaii in collaboration with Hawaii Volcanoes National Park, the University of Hawaii, Manoa, and the USDA Forest Service. I spent my days hiking up and down the slopes of Mauna Loa volcano equipped with a sling-shot to collect koa phyllodes from the forest canopy in order to assess the water-use efficiency of these magnificent trees. I'll be analyzing my data for my thesis work leading to a Master of Forest Science under the direction of Dr. Graeme Berlyn at Yale University.
Alder Keleman, MESc/MA 2005
Genealogies of Globalization: Stories of crop loss, crop persistence, and the formal and informal economies in Northern Mexico
Location: North America, Mexico
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On a break from research to attend a conference in Oaxaca, TRI Fellow Alder Keleman explores the 3000-year old Zapotec ruins at Monte Alban.
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Located in the south of the Mexican state of Sonora, the municipality of Alamos lies just miles from one of the epicenters of the Green Revolution. One of the few regions in the state where small-scale dry-land farming is still practiced, Alamos, too, has adopted increasing degrees of mechanization in past decades, and observers have expressed the concern that a concurrent loss of native crop varieties has occurred. In this context, the goals of the present project were twofold: first, to assess the persistence of native varities of bean, corn, and squash in the region, using data from the Tucson-based seed bank, Native Seeds/SEARCH, as a baseline; and second to examine relationships between the state of regional crop diversity and broader socioeconomic and environmental trends.
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On Ejido La Higuera, an older farmer plows his soon-to-be maize field with mules. While many farmers in the region have taken to the practice of hiring a tractor, traditional plowing methods remain a common method of cultivation.
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Data gathered through a combination of surveys, interviews, and participant observation suggest that farmers in the Alamos region do continue to plant a wide variety of native crops, exhibiting consistent within-farm diversity of beans and squash. However, while a number of varieties of native corn are still grown in the region as a whole, within-farm corn diversity is low. It is uncommon to find more than two to three corn varieties grown on a single farm, and the loss of particular corn varieties is clearly marked in Alamos farmers’ memories. Deeper exploration of the causes of such losses identified prolonged drought, increased cash flow resulting from a rise in drug trafficking in the local economy, and changes in local tastes and preferences all emerged as interdependent influences on the persistence of native crops.
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