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2011

Physical and Environmental Geography

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Articles 1 - 30 of 63

Full-Text Articles in Geography

Investigating The Impact Of Restricted Irrigation Practices On Soil Moisture Variability And Distribution In A Dry Farmed Vineyard Site, Boise, Idaho, J. Duffin, David Wilkins, J. Guenther Dec 2011

Investigating The Impact Of Restricted Irrigation Practices On Soil Moisture Variability And Distribution In A Dry Farmed Vineyard Site, Boise, Idaho, J. Duffin, David Wilkins, J. Guenther

David E. Wilkins

Changing climate in semiarid regions may result in increased water stresses for agricultural production as timing and form of precipitation may result in diminished surface water for irrigation. To prepare for these changing conditions, studies are being conducted on the possibility of dry farmed agriculture as an alternative to irrigated production. This study specifically investigates the ability to grow productive wine grapes with limited or zero irrigation in the Boise Front Foothills, West Foothills TIC Vineyard, located in a climate zone receiving less than 300 mm of annual precipitation. Traditional vineyard performance factors such as planting densities, soil type, rootstock, …


Sophomore Field Experiences As An Introduction To The Nature Of Geosciences: Data Collection And Analysis Using Dendrochronology, David Wilkins, M. Kunkel Dec 2011

Sophomore Field Experiences As An Introduction To The Nature Of Geosciences: Data Collection And Analysis Using Dendrochronology, David Wilkins, M. Kunkel

David E. Wilkins

Opportunities for field experiences are often presented as a primary reason that undergraduate students gravitate towards geosciences as a major field of study. What those students may not understand is that, for professional geoscientists, field experiences go beyond the freshman-level field trip, and students may overlook the processes of observation, data collection and analysis that are inherent to the science. The Department of Geosciences at Boise State has developed a set of sophomore field experience courses designed to "set the hook" into new majors and prepare them for field experiences in upper division coursework. These sophomore courses have been shown …


Missouri National Recreational River, Natural Resource Condition Assessment, Kevin J. Stark, Lucas J. Danzinger, Michael R. Komp, Andy J. Nadeau, Shannon Amberg, Eric J. Iverson, David Kadlec, Barry Drazkowski Dec 2011

Missouri National Recreational River, Natural Resource Condition Assessment, Kevin J. Stark, Lucas J. Danzinger, Michael R. Komp, Andy J. Nadeau, Shannon Amberg, Eric J. Iverson, David Kadlec, Barry Drazkowski

United States National Park Service: Publications

Executive Summary

As a unit in the National Park Service (NPS), Missouri National Recreational River (MNRR) is responsible for the management and conservation of natural resources within its boundaries. This mandate is supported by the National Park Service Organic Act of 1916, which directs the NPS to:

conserve the scenery and natural and historic objects and the wildlife therein and to provide for the enjoyment of the same in such a manner and by such means as will leave them unimpaired for the enjoyment of future generations.

In 2003, NPS Water Resources Division received funding through the Natural Resource Challenge …


Scotts Bluff National Monument Plant Community Composition And Structure Monitoring, 2011 Annual Report, Isabel W. Ashton, Michael Prowatzke, Michael R. Bynum, Tim Shepherd, Stephen K. Wilson, Kara Paintner-Green Dec 2011

Scotts Bluff National Monument Plant Community Composition And Structure Monitoring, 2011 Annual Report, Isabel W. Ashton, Michael Prowatzke, Michael R. Bynum, Tim Shepherd, Stephen K. Wilson, Kara Paintner-Green

United States National Park Service: Publications

Executive Summary

The Northern Great Plains Inventory & Monitoring Network (NGPN) was established to develop and provide scientifically credible information on the current status and long-term trends of the composition, structure, and function of ecosystems in thirteen parks located in five northern Great Plains states. NGPN identified upland plant communities, exotic plant early detection, and riparian lowland communities as vital signs that can be used to better understand the condition of terrestrial park ecosystems (Gitzen et al. 2010). Upland and riparian ecosystems are important targets for vegetation monitoring because the status and trends in plant communities provide critical insights into …


Agate Fossil Beds National Monument Plant Community Composition And Structure Monitoring, 2011 Annual Report, Isabel W. Ashton, Michael Prowatzke, Michael R. Bynum, Tim Shepherd, Stephen K. Wilson, Kara Paintner-Green Dec 2011

Agate Fossil Beds National Monument Plant Community Composition And Structure Monitoring, 2011 Annual Report, Isabel W. Ashton, Michael Prowatzke, Michael R. Bynum, Tim Shepherd, Stephen K. Wilson, Kara Paintner-Green

United States National Park Service: Publications

Executive Summary

The Northern Great Plains Inventory & Monitoring Network (NGPN) was established to develop and provide scientifically credible information on the current status and long-term trends of the composition, structure, and function of ecosystems in thirteen parks located in five northern Great Plains states. NGPN identified upland plant communities, exotic plant early detection, and riparian lowland communities as vital signs that can be used to better understand the condition of terrestrial park ecosystems (Gitzen et al. 2010). Upland and riparian ecosystems are important targets for vegetation monitoring because the status and trends in plant communities provide critical insights into …


Perception Of Aquifer Depletion And The Effects Of Land Use Change Across The Madaba Plain, Jordan, Mohammad Salem Dec 2011

Perception Of Aquifer Depletion And The Effects Of Land Use Change Across The Madaba Plain, Jordan, Mohammad Salem

Graduate Theses and Dissertations

In Jordan, demand for water for agricultural purposes has put a high strain on aquifer resources. Water mining, erosion, and desertification have all increased as global temperatures rise. This along with fragmentation of the landscape have altered the environment in a profound way. The Madaba Plain was chosen for this study due to the agricultural activities that take place there, as well as the proximity to a number of population centers. The purpose of the study is to examine how fragmentation of irrigated landscape has affected the aquifers underneath, while taking into account perceptions of risk of the local population. …


Spatial Analysis Of Fatal Automobile Crashes In Kentucky, William Nathan Oris Dec 2011

Spatial Analysis Of Fatal Automobile Crashes In Kentucky, William Nathan Oris

Masters Theses & Specialist Projects

Fatal automobile crashes have claimed the lives of over 33,000 people each year in the United States since 1995. As in any point event, fatal crash events do not occur randomly in time or space. The objectives of this study were to identify spatial patterns and hot spots in FARS (Fatal Analysis Reporting System) fatal crash events based on temporal and demographic characteristics. The methods employed included 1) rate calculation using FARS points and average daily traffic flow; 2) planar kernel density estimation of FARS crash events based on temporal and demographic attributes within the data; and 3) two case …


Multiple Storm Event Impacts On Epikarst Storage And Transport Of Organic Soil Amendments In South-Central Kentucky, Sean M. Vanderhoff Dec 2011

Multiple Storm Event Impacts On Epikarst Storage And Transport Of Organic Soil Amendments In South-Central Kentucky, Sean M. Vanderhoff

Masters Theses & Specialist Projects

The groundwater in agricultural karst areas is susceptible to contamination from organic soil amendments and pesticides. During major storm events during 2011, dye traces were initiated using sulphorhodamine-B, fluorescein and eosine in a groundwater recharge area where manure was applied to the ground. Fecal coliform samples were collected from significant storm events from January-September 2011. Water samples and geochemical data were collected every four hours before, during, and between the storm events from a waterfall in Crumps cave flowing from the known recharge area to track the transport and residence time of the epikarst water and organic soil amendments during …


Quasi‐Hidden Markov Model And Its Applications In Cluster Analysis Of Earthquake Catalogs, Zhengxiao Wu Dec 2011

Quasi‐Hidden Markov Model And Its Applications In Cluster Analysis Of Earthquake Catalogs, Zhengxiao Wu

Research Collection School of Economics

We identify a broad class of models, quasi-hidden Markov models (QHMMs), which include hidden Markov models (HMMs) as special cases. Applying the QHMM framework, this paper studies how an earthquake cluster propagates statistically. Two QHMMs are used to describe two different propagating patterns. The “mother-and-kids” model regards the first shock in an earthquake cluster as “mother” and the aftershocks as “kids,” which occur in a neighborhood centered by the mother. In the “domino” model, however, the next aftershock strikes in a neighborhood centered by the most recent previous earthquake in the cluster, and therefore aftershocks act like dominoes. As the …


Land Systems Of The Kimberley Region, Western Australia, A L. Payne, N Schoknecht Dec 2011

Land Systems Of The Kimberley Region, Western Australia, A L. Payne, N Schoknecht

Technical Bulletins

The Land Systems of the Kimberley Region Report describes and maps the landscapes, soils and vegetation of the Kimberley region. This report is a consolidation of surveys carried out by different organisations, across different areas of the Kimberley, since the 1940s. The Kimberley region, as defined in this bulletin, covers 330 070km². The report categorises the Kimberley region into 111 land systems. Under each land system, the report identifies the vulnerabilities of those areas, and provides recommendations on how to achieve sustainable use. The report also publishes pasture types for the entire region and the grazing potential for each pasture, …


The Temporal And Spatial Connectivity Of The Gambles Mill Corridor, Richmond, Va, R.M. Price, K. Billups, S. Bodner, M. Burbank, L. Cohan, S. Elliott, C. Landesberg, G. Leonard, J. Marconi, M. Mcgovern, J. Petrosino, A. Phadke, C. Phelan, A. Purdy, David S. Salisbury Nov 2011

The Temporal And Spatial Connectivity Of The Gambles Mill Corridor, Richmond, Va, R.M. Price, K. Billups, S. Bodner, M. Burbank, L. Cohan, S. Elliott, C. Landesberg, G. Leonard, J. Marconi, M. Mcgovern, J. Petrosino, A. Phadke, C. Phelan, A. Purdy, David S. Salisbury

Geography and the Environment Poster Presentations

The City of Richmond and the Virginia Department of Transportation proposed to rehabilitate the Gambles Mill Trail connecting the University of Richmond (UR) to the intersection of Huguenot and River Road. Planners envision this trail as a sustainable model for the reduction of nutrient and sediment flow and as a vital path in a city-wide network of bike and pedestrian trails. Meanwhile, UR also proposes to rehabilitate the corridor in their new Master Plan. Nevertheless, until now, no substantive studies exist on the trail or the corridor linking the trail to the south side of the James River through the …


Beyond The Epsilon Band: Polygonal Modeling Of Gradation/Uncertainty In Area-Class Maps, Barry J. Kronenfeld Nov 2011

Beyond The Epsilon Band: Polygonal Modeling Of Gradation/Uncertainty In Area-Class Maps, Barry J. Kronenfeld

Barry J. Kronenfeld

A spatial modeling technique is proposed to represent boundary uncertainty or gradation on area-class maps using a simple polygon tessellation with designated zones of indeterminacy or transition zones. The transition zone can be conceptualized as a dual of the epsilon band, but is more flexible and allows for a wide range of polygonal configurations, including polygons with sinuous boundaries, spurs, three-way transition zones, and null polygons. The model is specified using the medial axis to capture the general shape characteristics of a transition zone. Graph theoretic representation of an extended version of the medial axis captures key junctions in both …


Future Flooding Impacts On Transportation Infrastructure And Traffic Patterns Resulting From Climate Change, Heejun Chang, Martin Lafrenz, Il-Won Jung, Miguel A. Figliozzi, Rolando Melgoza, David Ruelas, Deena Platman, Cindy Pederson Nov 2011

Future Flooding Impacts On Transportation Infrastructure And Traffic Patterns Resulting From Climate Change, Heejun Chang, Martin Lafrenz, Il-Won Jung, Miguel A. Figliozzi, Rolando Melgoza, David Ruelas, Deena Platman, Cindy Pederson

Geography Faculty Publications and Presentations

This study investigated potential impacts of climate change on travel disruption resulting from road closures in two urban watersheds in the Portland metropolitan area. We used ensemble climate change scenarios, a hydrologic model, stream channel survey, a hydraulic model, and a travel forecast model to develop an integrated impact assessment method. High-resolution climate change scenarios are based on the combinations of two emission scenarios and eight general circulation models. The Precipitation-Runoff Modeling System was calibrated and validated for the period 1988-2006, and simulated for determining the probability of floods from 2020-2049. We surveyed stream cross sections at five road crossings …


Beyond The Epsilon Band: Polygonal Modeling Of Gradation/Uncertainty In Area-Class Maps, Barry J. Kronenfeld Nov 2011

Beyond The Epsilon Band: Polygonal Modeling Of Gradation/Uncertainty In Area-Class Maps, Barry J. Kronenfeld

Faculty Research and Creative Activity

A spatial modeling technique is proposed to represent boundary uncertainty or gradation on area-class maps using a simple polygon tessellation with designated zones of indeterminacy or transition zones. The transition zone can be conceptualized as a dual of the epsilon band, but is more flexible and allows for a wide range of polygonal configurations, including polygons with sinuous boundaries, spurs, three-way transition zones, and null polygons. The model is specified using the medial axis to capture the general shape characteristics of a transition zone. Graph theoretic representation of an extended version of the medial axis captures key junctions in both …


Beyond The Epsilon Band: Polygonal Modeling Of Gradation/Uncertainty In Area-Class Maps, Barry Kronenfeld Nov 2011

Beyond The Epsilon Band: Polygonal Modeling Of Gradation/Uncertainty In Area-Class Maps, Barry Kronenfeld

Faculty Research and Creative Activity

A spatial modeling technique is proposed to represent boundary uncertainty or gradation on area-class maps using a simple polygon tessellation with designated zones of indeterminacy or transition zones. The transition zone can be conceptualized as a dual of the epsilon band, but is more flexible and allows for a wide range of polygonal configurations, including polygons with sinuous boundaries, spurs, three-way transition zones, and null polygons. The model is specified using the medial axis to capture the general shape characteristics of a transition zone. Graph theoretic representation of an extended version of the medial axis captures key junctions in both …


Surface Modeling Topsoil Distribution On A Reclaimed Coal-Mine Site At Blackmesa Mine Complex, Kayenta, Arizona, Janine Ferarese Oct 2011

Surface Modeling Topsoil Distribution On A Reclaimed Coal-Mine Site At Blackmesa Mine Complex, Kayenta, Arizona, Janine Ferarese

Geography and the Environment: Graduate Student Capstones

A necessary precursor to ensure proper vegetation growth on reclaimed coal-mine areas is even distribution of topsoil. This capstone discusses development of surface models to describe the accurate determination and visualization of the distribution of topsoil. Prediction surfaces from topsoil-depth point samples were created using the surface interpolation methods, Inverse Distance Weighted and Kriging. The validity and accuracy of each method was assessed to determine the best method to evaluate actual topsoil distribution at a coal mining site. The model can be utilized by non- spatially trained personnel working in the mining arena as an aid in assessing how appropriately …


Exploiting The Power Law Distribution Properties Of Satellite Fire Redaiative Power Retrials: A Method To Estimate Fire Radiative Energy And Biomass Burned From Sparse Satellite Observations, S. S. Kumar, David P. Roy, L. Boschetti, R. Kremens Oct 2011

Exploiting The Power Law Distribution Properties Of Satellite Fire Redaiative Power Retrials: A Method To Estimate Fire Radiative Energy And Biomass Burned From Sparse Satellite Observations, S. S. Kumar, David P. Roy, L. Boschetti, R. Kremens

GSCE Faculty Publications

Instantaneous estimates of the power released by fire (fire radiative power, FRP) are available with satellite active fire detection products. The temporal integral of FRP provides an estimate of the fire radiative energy (FRE) that is related linearly to the amount of biomass burned needed by the atmospheric emissions modeling community. The FRE, however, is sensitive to satellite temporal and spatial FRP undersampling due to infrequent satellite overpasses, cloud and smoke obscuration, and failure to detect cool and/or small fires. Satellite FRPs derived over individual burned areas and fires have been observed to exhibit power law distributions. This property is …


Review Of Hard Grass: Life On The Crazy Woman Bison Ranch. By Mary Zeiss Stange, Linda M. Hasselstrom Oct 2011

Review Of Hard Grass: Life On The Crazy Woman Bison Ranch. By Mary Zeiss Stange, Linda M. Hasselstrom

Great Plains Research: A Journal of Natural and Social Sciences

Twenty years ago, Stange and her husband traded a modest New Jersey house for seven square miles of overgrazed prairie and set out to right the wrongs done to a place that had been mismanaged ecologically as well as environmentally. The restoration begins disastrously with llamas before it proceeds to success with bison. Her narration includes her own experiences, but most of her essays are serious, in-depth studies of the broader topics that constitute life in the great grasslands spreading across the interior of the country. She begins with prehistory, analyzing the evolution of both plants and animals in the …


Carbon Storage And Cycling Of Reclaimed Mine Soils In Southeastern Kentucky, Alice Jones, Kelly Barber, Peter Acton, James Fox Sep 2011

Carbon Storage And Cycling Of Reclaimed Mine Soils In Southeastern Kentucky, Alice Jones, Kelly Barber, Peter Acton, James Fox

Alice Jones

Since the passage of the Surface Mining and Reclamation Act (SMCRA) in 1977, the most common type of surface mine reclamation is heavy compaction followed by grass seeding. To promote better vegetative recovery after mining, the Appalachian Regional Reforestation Initiative (ARRI) promotes leaving the top four feet of fill material loose and planting a seedling mix of native hardwood trees. This study aims to quantify the effects of the resulting soil bulk densities on decomposition processes through the analysis of carbon storage and cycling in the soil column. Soil carbon storage mechanisms are divided into specific size classes/pools, each corresponding …


Professional Development For Graduate Students Through Outreach Partnerships With Science Learning Centers, Karen Viskupic, Jennie Rylee, Cindy Busche, Sara Focht, David Cannamela, Annelise Carleton-Hug, James Belthoff, David Wilkins Sep 2011

Professional Development For Graduate Students Through Outreach Partnerships With Science Learning Centers, Karen Viskupic, Jennie Rylee, Cindy Busche, Sara Focht, David Cannamela, Annelise Carleton-Hug, James Belthoff, David Wilkins

David E. Wilkins

With funding from the National Science Foundation’s Graduate STEM Fellows in K-12 Education program (GK-12), students from Boise State University’s graduate programs in biology and geosciences gain experience in curriculum development and delivery in a wide range of settings. The project uniquely partners graduate students with educators at three informal science centers that use their settings to focus on science and environmental issues of local, regional, and global importance. Two-three graduate students per year (GK-12 Fellows) are placed at each learning center where they work to create, modify, and deliver learning activities that incorporate local and regional themes as well …


Homestead National Monument Of America, Geologic Resources Inventory Report, J. Graham Sep 2011

Homestead National Monument Of America, Geologic Resources Inventory Report, J. Graham

United States National Park Service: Publications

Executive Summary

This report accompanies the digital geologic map data for Homestead National Monument of America in Nebraska, produced by the Geologic Resources Division in collaboration with its partners. It contains information relevant to resource management and scientific research. This document incorporates preexisting geologic information and does not include new data or additional fieldwork.

Established as a memorial to pioneer life and the Homestead Act of 1862, Homestead National Monument of America preserves approximately 92 ha (228 acres) of terraced grassland and riparian, floodplain environments. Included in the monument are about 40 ha (100 acres) of restored tallgrass prairie and …


Coca And Conservation: Cultivation, Eradication, And Trafficking In The Amazon Borderlands, David S. Salisbury, C. Fagan Aug 2011

Coca And Conservation: Cultivation, Eradication, And Trafficking In The Amazon Borderlands, David S. Salisbury, C. Fagan

Geography and the Environment Faculty Publications

The cultivation and traffic of coca, Erythrolxylum coca, and coca derivatives remain understudied threats to the conservation of the Amazon rainforest. Currently the crop is transforming land use and livelihoods in the ecologically and culturally rich borderlands of Amazonian Peru. The isolated nature of this region characterized by indigenous populations (both settled and uncontacted), conservation units, resource concessions, and a lack of state presence provides fertile ground for the boom and bust cycle of coca production and facilitates the international transport of the product to neighboring Brazil. This paper explores the social and environmental impacts of coca production, eradication, and …


From Lakes To Plants: Spatial Assessment Of Vegetation Dynamics Along 52 Disappearing Lakes In The Boreal Forests Of Alaska From 1984-2009 In The Yukon Flats Wildlife Refuge, Steve Ewest Jul 2011

From Lakes To Plants: Spatial Assessment Of Vegetation Dynamics Along 52 Disappearing Lakes In The Boreal Forests Of Alaska From 1984-2009 In The Yukon Flats Wildlife Refuge, Steve Ewest

Geography and the Environment: Graduate Student Capstones

A spatial assessment of vegetation change along the areas of shrinking lakes was conducted in 2011. The analysis utilized Landsat TM/ETM imagery bands 3 and 4 to calculate NDVI (normalized difference vegetation index) from 1984 to 2009 and applied cell and zonal statistics to measure the change as well as create an animation of the change. Also, three 30 meter bands and the zonal averages for the maximum values were assessed. The band in the 60-90 buffer bands has the greatest ratio amount of the maximum vegetation values when compared to the 0-30 meter and the 30-60 meter buffered bands. …


Geopolitics Of The Kaliningrad Exclave And Enclave: Russian And Eu Perspectives, Alexander Diener, Joshua Hagen Jul 2011

Geopolitics Of The Kaliningrad Exclave And Enclave: Russian And Eu Perspectives, Alexander Diener, Joshua Hagen

Geography Faculty Research

Two U.S. political geographers examine a range of geopolitical issues associated with the shifting sovereignty of Russia's Kaliningrad Oblast (a part of the former German province of East Prussia) during the 20th century, as well as the region's evolving geopolitical status as a consequence of the European Union's enlargement to embrace Poland and Lithuania. They argue that Kaliningrad today can be considered a "double" borderland, situated simultaneously on the European Union's border with Russia as well as physically separated from Russia, its home country, by the surrounding land boundaries of EU states. Although technically neither an exclave nor an enclave, …


Soil Development Processes On The Western Slope Of The Southern Sierra Nevada Mountains: A Geographic Study, Kristopher (Kris) Osterloh Jun 2011

Soil Development Processes On The Western Slope Of The Southern Sierra Nevada Mountains: A Geographic Study, Kristopher (Kris) Osterloh

Earth and Soil Sciences

No abstract provided.


The Ecology Of San Luis Obispo: A Children's Book, Heidi Van Campen Jun 2011

The Ecology Of San Luis Obispo: A Children's Book, Heidi Van Campen

Social Sciences

San Luis Obispo is one of the most loved places in the world by its residents and visitors. Located halfway between San Francisco and Los Angeles, San Luis Obispo is the heart of California's Central Coast. However, this paper is not about the present-day cities or residents. It is an ecological history; the story of life and land over time.

Historians tend to treat nature as the setting for history, rather than a participant. Ecology is a history written knowing that we shape our environment and it shapes us.

This is a story of the ecology of San Luis Obispo.


Assessing Seasonal Features Of Tropical Forests Using Remote Sensing, Roberto Bonifaz-Alfonzo May 2011

Assessing Seasonal Features Of Tropical Forests Using Remote Sensing, Roberto Bonifaz-Alfonzo

Department of Geography: Dissertations, Theses, and Student Research

Tropical forests are key components of the biogeochemical cycles, complex in structure, diversity and dynamics, also, tropical regions have been deforested and modified by human activities particularly for agriculture. Understanding the inter-annual and intra-annual variation dynamics of tropical regions could give valuable information on temporal characteristics of ecosystems behavior which is important for mapping and monitoring. This dissertation assesses seasonal and inter-annual changes in the tropical land cover that may be related to changes in the natural environment and/or human activities. Research was focused on the Mayan forest located in southern Mexico and Northwest Guatemala, one of the northern-most important …


Wallace-Mcharg’S Plans For Greater Baltimore, Garrett Power May 2011

Wallace-Mcharg’S Plans For Greater Baltimore, Garrett Power

Garrett Power

This essay considers the growth of the partnership between David Wallace and Ian McHarg into one of the nation’s dominant urban design and environmental planning firms. It focuses on the firm’s undertaking in the Greater Baltimore region in the 1950’s, 1960’s, and 1970’s. With the benefit of fifty years of hindsight it looks at the successes and failures of their plans for Charles Center, the Green Spring and Worthington Valleys, and the Inner Harbor. Surprisingly, prize-winning innovations praised in one generation came to be judged as the design flaws of the next. Less surprisingly, their plans to “design with nature” …


Spatial Variation In Organic Carbon And Stable Isotope Composition Of Lake Sediments At Laguna Zoncho, Costa Rica, Zachary P Taylor May 2011

Spatial Variation In Organic Carbon And Stable Isotope Composition Of Lake Sediments At Laguna Zoncho, Costa Rica, Zachary P Taylor

Doctoral Dissertations

Lake sediments are valuable paleoenvironmental archives that provide information on past climate and land-use change. Most lake sediment studies rely on a single core, usually recovered from the center of a lake, and do not consider spatial variability in the lake basin. My dissertation presents a spatially-explicit record of prehistoric agriculture from Laguna Zoncho, Costa Rica and evaluates spatial variability in lake sediment proxies based on a network of five sediment cores. Results extend earlier proxy analyses of a single core collected near the center of the lake, which documented prehistoric agriculture and forest clearance from 3000 to about 500 …


Defining The Regional And Seasonal Climatic Response Of Long Douglas-Fir Tree-Ring Chronologies In Central Mexico, Grant Howard West May 2011

Defining The Regional And Seasonal Climatic Response Of Long Douglas-Fir Tree-Ring Chronologies In Central Mexico, Grant Howard West

Graduate Theses and Dissertations

Problems with instrumental climate data and difficulties arising from the distribution of sensitive, long-term tree-ring chronologies across Mexico's complex terrain have made it difficult to model the climate signal of tree-rings in Mexico. The objective of this research is to utilize the improved long-term, high-resolution, gridded instrumental climate dataset for Mexico recently developed by Zhu and Lettenmaier (2007) to document the climate signal of Douglas-fir in central Mexico. Through correlation analysis between five Douglas-fir tree-ring chronologies created by the University of Arkansas-Fayetteville Tree-Ring Laboratory and Zhu and Lettenmaier's (2007) gridded historical climate dataset, this research aims to define the regional …