Ph.D., Antioch University, 2018, Antioch New England: Environmental Studies

Changes in forest cover especially changes within tropical forests, affect global climate change, together with ecosystems and forest carbon. Forests play a key role in both carbon emission and carbon sequestration. Efforts to reduce emissions through reduced deforestation and degradation of forests have become a common discussion among scientists and politicians under the auspices of the United Nations Programme on Reducing Emissions from Deforestation and Forest Degradation (UN-REDD Programme). This dissertation research assessed the impacts of land use land cover change upon ecosystem services from a protected area focusing on forest carbon distribution and vegetation mapping using remote sensing and geographical information systems (GIS). I also assessed Rwanda's preparedness in the United Nations global program, Reducing Emissions from Deforestation and forest Degradation, Measuring, Monitoring, Reporting, and Verifying (REDD+MMRV). I carried out research in Nyungwe National Park (NNP), one of four National Parks of Rwanda. NNP is a montane tropical forest located in the Albertine Rift, one of the most biodiverse places in central and east Africa. I used remote sensing and field data collection from December 2011 and July 2012 in the western part of the Park to assess distribution and quantities of aboveground (ABG) forest carbon using generalized allometric functions. Using Landsat data together with 2009 high resolution color orthophotos and groundtruthing, I analyzed land cover changes between 1986 and 2011 for NNP. The land-use land cover change analysis showed that between 1986 and 1995 there was a minor increase in forest cover from 53% to 58% while from 1995-2003 a substantial decrease in forest cover occurred. Between 2003 and 2011 was a period of recovery with forest cover increasing by 59%. Vegetation analysis based on a 2009 Park biodiversity survey yielded 13 vegetation communities based on dominant and co-dominant species. Macaranga kilimandschar (open full item for complete abstract)

Committee: Beth Kaplin PhD (Committee Chair); Peter Palmiotto DF (Committee Member); Naikoa Aguilar-Amuchastegui PhD (Committee Member) Subjects: Environmental Studies; Geographic Information Science; Remote Sensing

PhD, University of Cincinnati, 2016, Arts and Sciences: Biological Sciences

Tropical and temperate plant species in forests around the world are threatened by human-induced land-use changes which produce various outcomes such as increased spread of invasive species, habitat fragmentation, and alterations of community structure among others. These factors can lower population sizes and genetic diversity levels of native plant species, making the risk of extinction imminent. Methodologies to mitigate such effects can involve introducing endangered plant species back to their native habitats either via in situ management of exploited species, or ex situ conservation. To study such species conservation, highly-replicated predictive computer modeling can be an inexpensive tool to suggest those scenarios that can better maintain viable population sizes and genetic diversity levels over the long term, since field studies are less feasible given the limited time and resources available. I used a species-specific, spatially-explicit, individual-based computer program (NEWGARDEN) capable of modeling and monitoring plant population growth and genetic diversity patterns in simulated stands over time to comparatively model various restoration methodologies for different threatened tree species. Specifically, I examined: 1) effective reintroduction geometries of the American chestnut; 2) sustainable spatial deforestation patterns for long-lived canopy tree species in tropical lowland rain forests (TLRFs); and 3) seed collection strategies capable of maximizing the harvest of genetic variation from rare TLRF tree species for use in developing ex situ rescue populations. These species conservation methodologies were tested under differing offspring and pollen dispersal distances, as this life-history trait can affect the spatial distribution of allelic diversity in populations. Results indicate that for reintroductions of the American chestnut, planting and stewarding a limited number of individuals at least 100m in from the preserve border (for (open full item for complete abstract)

Committee: Steven Rogstad Ph.D. (Committee Chair); Theresa Culley Ph.D. (Committee Member); Stephen Matter Ph.D. (Committee Member); Eric Maurer Ph.D. (Committee Member); Stephan Pelikan Ph.D. (Committee Member) Subjects: Botany

Master of Science (MS), Ohio University, 2015, Environmental Studies (Voinovich)

This thesis is an analysis of land use patterns in the Copan Valley, Honduras. It is a comparative, GIS-based analysis of the archaeological/population site data of the ancient Copan Maya population (A.D. 250-1300) and the 1978 modern Copan Valley population. These two populations were compared to ascertain the resilience of the Valley's ecosystem over time. Time series data from the ancient Maya was combined with mean center and standard distances tests on both populations and these were overlain onto slope and aspect data to determine how both populations utilized similar landscapes. Results demonstrate that the ancient Mayan utilization of the valley was nonresilient, and unsustainable, while the 1978 population was also non resilient, and only currently sustainable due to outside markets.

Committee: AnnCorinne Freter-Abrams (Committee Chair); Elliot Abrams (Committee Member); Dorothy Sack (Committee Member) Subjects: Agricultural Economics; Agriculture; Ancient Civilizations; Ancient History; Archaeology; Cultural Anthropology; Demography; Ecology; Environmental Philosophy; Environmental Science; Environmental Studies; Geographic Information Science; Latin American History; Latin American Studies; Sustainability