A computer controlled dry kiln system, designed and assembled at Virginia Tech, was used in a comparison study of end check damage and acoustic emission count rate for red oak wood samples using two variations of a drying schedule based upon a standard 4/4 red oak drying schedule (T4D2). Time was the controlling variable for the system. In run A, the lumber samples were dried using eight large step changes in temperature and relative humidity. In run B, a similar charge was dried over the same time period using 48 smaller step changes in temperature and relative humidity. The lumber samples that were dried with the schedule featuring large changes in temperature and relative humidity suffered much more extensive end check damage than the wood samples dried with a schedule employing smaller changes in temperature and humidity. The acoustic emission count rate data were not recorded in the final tests due to equipment malfunction. Acoustic emission count rate data recorded from preliminary drying runs indicated that the acoustic emission count rate from a sample board increases with large changes in the ambient air temperature and relative humidity. It then decreases to zero as the wood surfaces achieve an equilibrium state. The automated kiln control system performed successfully. / M.S.

Small-scale timber farming provides alternative income for growers selling to forestry, procurement companies and timber suppliers or agents. The research used focus groups and structured questionnaires in the Sokhulu area to determine the contribution of small-scale timber farming to enhance sustainable livelihood. The Sustainable Livelihood Framework measured livelihood levels of different grower types in terms of access to natural, human, financial, social and physical assets. Findings show that timber suppliers had a higher asset composition, than growers selling to companies or growers selling to timber suppliers. Households lacking access to forestry resources sold timber to agents and households wanting to avoid harvesting and transport risks sold timber to suppliers. Timber farming contributes income, employment and business opportunities towards alleviating poverty rather than providing a complete solution. Tree harvesting support households during financial hardship and reduce vulnerability through diversified livelihood strategies. Disadvantages include: trees taking time to mature while immediate income is required, trees exposed to natural hazards, cheating by local harvesting and transport contractors and timber plot sales sometimes do not receive the agreed price. Despite disadvantages, timber farming provide economic benefits and further studies are needed to determine income level on mature trees, by-product sales and whether higher prices for more tonnage will sustain households that wait for tree maturity, thereby determining optimal break-even point for rural timber farmers. / Environmental Sciences / M.A. (Human Ecolgy)

Small-scale timber farming provides alternative income for growers selling to forestry, procurement companies and timber suppliers or agents. The research used focus groups and structured questionnaires in the Sokhulu area to determine the contribution of small-scale timber farming to enhance sustainable livelihood. The Sustainable Livelihood Framework measured livelihood levels of different grower types in terms of access to natural, human, financial, social and physical assets. Findings show that timber suppliers had a higher asset composition, than growers selling to companies or growers selling to timber suppliers. Households lacking access to forestry resources sold timber to agents and households wanting to avoid harvesting and transport risks sold timber to suppliers. Timber farming contributes income, employment and business opportunities towards alleviating poverty rather than providing a complete solution. Tree harvesting support households during financial hardship and reduce vulnerability through diversified livelihood strategies. Disadvantages include: trees taking time to mature while immediate income is required, trees exposed to natural hazards, cheating by local harvesting and transport contractors and timber plot sales sometimes do not receive the agreed price. Despite disadvantages, timber farming provide economic benefits and further studies are needed to determine income level on mature trees, by-product sales and whether higher prices for more tonnage will sustain households that wait for tree maturity, thereby determining optimal break-even point for rural timber farmers. / Environmental Sciences / M.A. (Human Ecolgy)

Progress in tree biotechnology initially trailed behind agricultural crops due to their long life cycle, difficult tissue culture and regeneration protocols, and their abundance in natural forests. However, rapid global deforestation rates, together with an increased world demand for pulp, paper and timber products, have prompted scientific and commercial focus to improve genetic timber stocks. South Africa, a tree-poor country (where indigenous forests are protected), has relied almost solely on exotic plantations to meet its demand for timber. A pioneer study investigating the feasibility of using direct (biolistic) and indirect (Agrobacterium-mediated) methods for gene transfer was undertaken in Pinus patula Schiede et Deppe, a Mexican softwood and a forerunner for saw timber, pulpwood and paper in the South African forest industries. The aim of the transformation methods was to impart herbicide resistance to the trees. This was achieved via the introduction of a bar-GUS pAHC25 cassette under the control of the ubiquitin promoter. To provide target material for transformation, two in vitro micropropagation pathways were used: somatic embryogenesis and organogenesis. Both embryonal suspensor masses (ESM) and somatic embryos at various stages of development were initially used as target explants for the biolistic study using an established in vitro protocol. A stepwise selection was implemented in order to allow transformed (particularly bombarded) cultures the opportunity to regenerate under selection pressure using MSG3 maintenance medium supplemented with BASTA® herbicide at 1 mg l ¯¹ followed by 3 mg l¯¹ active ingredient at the next subculture. Biolistic transgene delivery was more efficient when sorbitol was included in the pre-bombardment medium enabling use of higher vacuum and shooting pressures, without lowering the regeneration potential of ESM significantly. Bombarded material from two genotypes (Lines 2 and 3) was regenerated to produce mature somatic embryos using an optimized regeneration regimen. The indirect study with Agrobacterium tumefaciens (LBA4404), transformed with the pAHC25 vector via triparental mating or heat shock, used a variety of target tissues including: mature somatic embryos, ESM and mature zygotic embryos (MZE's) - a novel in vitro system for P. patula. The Agrobacterium-mediated method resulted in optimized decontamination conditions using a combination of liquid MSG3 (or sterile dH₂O for mature embryos) supplemented with 500 mg l ¯¹ cefotaxime, with rotation, and sterile 65 mm Whatman No. 3 filter paper stacks, which avoided excess filtering and stress to transformation material. Further efforts to aid regeneration during the indirect study included L-proline post-transformation, though no mature somatic embryos were regenerated at the conclusion of the Agrobacterium-mediated study. Recovery of transformed ESM in both studies was best during the active growth phase 4-6 d after subculture. Regeneration with good somatic embryo potential was an exigent aspect in both transformation studies. Expression of positive histochemical GUS activity in all transformed material was confirmed by polymerase chain reaction (PCR) analysis indicating that Pinus patula tissue was amenable to transformation. A new bar PCR regime was implemented in P. patula. In the biolistic study, a higher transformation efficiency of bar amplicons (53%) than GUS amplicons (45%) was observed, reflecting their non-linked status on the pAHC25 transformation vector. This is the first report of biolistic transformation of P. patula that will allow for the production of transgenic ESM. The production of transgenic P. patula holds great promise for commercial development in the South African forestry industry. The application of transgenic trees in the timber industry is numerous but the aims most relevant to P. patula include wood modification and disease resistance to pathogens like pitch canker fungus. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.

Timber-dependent, rural communities in the Pacific Northwest face dramatic economic, political, and cultural change. New philosophies of forest management, primarily formulated in urban communities, require new approaches to the use and extraction of resources. What are the roles of rural communities that wish to adapt and sustain themselves? Two rural communities, one from Washington State, and one from Oregon, serve as case studies for coping with change. These cases build an ethnographic foundation on which to explore the rural-urban dynamic. The theories that elaborate the rural-urban relationship are central-place theory, and hermeneutic theory, which is used to understand the symbols and meaning of actions and ideas. Adaptive management, with new power relations, provides one possible solution to expedite the environmental and cultural sustainability of rural communities. / Graduation date: 1996

The ecologically and culturally rich Amazonian border zones are increasingly targeted for development and the exploitation of natural resources, even as these zones often double as existing or proposed sites for the conservation of biodiversity and protection of indigenous lands. Governmental and Non-Governmental Organizations alike project their goals from central offices onto borderland landscapes assumed to be empty of local people but full of valuable resources, biodiversity or development potential. Simultaneously, loggers, miners, drug traffickers, and others operate illegally or quasi-legally within these border zones and, in the absence of a strong governmental presence, cultivate the borderland's reputation as a violent hinterland. Within this complex borderland reality, the local people (indigenous and non-indigenous), largely invisible to authorities, struggle to survive with subsistence strategies while either negotiating with illegal interlopers to supplement their income or resisting them for their very survival. The resulting landscape is a tangle of overlapping and competing concessions, conservation units, and indigenous territories whose contestation and resulting confusion advances the agenda of illegal extractivists and drug traffickers. This study highlights the continued importance of fieldwork in geography. Here, field-based research provides insight into the poorly understood borderlands of Peru and Brazil. Research used a combination of participatory methods, Geographic Information Systems, ethnography, document research, and remote sensing to analyze mapping, logging, and coca cultivation within four borderland watersheds. These data were combined with regional data on coca eradication, resource concessions, conservation units, and indigenous territories from both Brazil and Peru. Field-based results demonstrate these borderlands to be highly contested and poorly mapped with an exploitative and poorly managed timber industry and a dynamic front of coca cultivation contributing to social disruption and environmental degradation. More fieldwork is needed to generate the geographic information necessary for sustainable development and conservation planning and to help local people defend their territory from illegal operators and the imposition of state resource concessions. Ecological Economic Zoning is recommended as a participatory policy framework to improve geographic information and long term planning. / text