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Full-Text Articles in Physical Sciences and Mathematics

Biomass Burning Fuel Consumption Rates: A Field Measurement Database, T. T. Van Leeuwen, G. R. Van Der Werf, A. A. Hoffmann, R. G. Detmers, G. Rücker, Nancy H. F. French, S. Archibald, J. A. Carvalho Jr, G. D. Cook, William J. De Groot, C. Hély, Eric S. Kasischke, S. Kloster, Jessica Mccarty, M. L. Pettinari, P. Savadogo, E. C. Alvarado, L. Boschetti, S. Manuri, C. P. Meyer, F. Siegert, L. A. Trollope, W. S. W. Trollope Dec 2014

Biomass Burning Fuel Consumption Rates: A Field Measurement Database, T. T. Van Leeuwen, G. R. Van Der Werf, A. A. Hoffmann, R. G. Detmers, G. Rücker, Nancy H. F. French, S. Archibald, J. A. Carvalho Jr, G. D. Cook, William J. De Groot, C. Hély, Eric S. Kasischke, S. Kloster, Jessica Mccarty, M. L. Pettinari, P. Savadogo, E. C. Alvarado, L. Boschetti, S. Manuri, C. P. Meyer, F. Siegert, L. A. Trollope, W. S. W. Trollope

Michigan Tech Research Institute Publications

Landscape fires show large variability in the amount of biomass or fuel consumed per unit area burned. Fuel consumption (FC) depends on the biomass available to burn and the fraction of the biomass that is actually combusted, and can be combined with estimates of area burned to assess emissions. While burned area can be detected from space and estimates are becoming more reliable due to improved algorithms and sensors, FC is usually modeled or taken selectively from the literature. We compiled the peer-reviewed literature on FC for various biomes and fuel categories to understand FC and its variability better, and …


Low Cost Infrared And Near Infrared Sensors For Uavs, Samuel T. Aden, James P. Bialas, Zachary Champion, Eugene Levin, Jessica L. Mccarty Nov 2014

Low Cost Infrared And Near Infrared Sensors For Uavs, Samuel T. Aden, James P. Bialas, Zachary Champion, Eugene Levin, Jessica L. Mccarty

Michigan Tech Research Institute Publications

Thermal remote sensing has a wide range of applications, though the extent of its use is inhibited by cost. Robotic and computer components are now widely available to consumers on a scale that makes thermal data a readily accessible resource. In this project, thermal imagery collected via a lightweight remote sensing Unmanned Aerial Vehicle (UAV) was used to create a surface temperature map for the purpose of providing wildland firefighting crews with a cost-effective and time-saving resource. The UAV system proved to be flexible, allowing for customized sensor packages to be designed that could include visible or infrared cameras, GPS, …


Remote Sensing Estimates Of Stand-Replacement Fires In Russia, 2002–2011, Alexander Krylov, Jessica L. Mccarty, Peter Potapov, Tatiana Loboda, Alexandra Tyukavina, Svetlana Turubanova, Matthew Hansen Oct 2014

Remote Sensing Estimates Of Stand-Replacement Fires In Russia, 2002–2011, Alexander Krylov, Jessica L. Mccarty, Peter Potapov, Tatiana Loboda, Alexandra Tyukavina, Svetlana Turubanova, Matthew Hansen

Michigan Tech Research Institute Publications

The presented study quantifies the proportion of stand-replacement fires in Russian forests through the integrated analysis of Landsat and Moderate Resolution Imaging Spectroradiometer (MODIS) data products. We employed 30 m Landsat Enhanced Thematic Mapper Plus derived tree canopy cover and decadal (2001–2012) forest cover loss (Hansen et al 2013 High-resolution global maps of 21st-century forest cover change Science 342 850–53) to identify forest extent and disturbance. These data were overlaid with 1 km MODIS active fire (earthdata.nasa.gov/data/near-real-time-data/firms) and 500 m regional burned area data (Loboda et al 2007 Regionally adaptable dNBR-based algorithm for burned area mapping from …


Information And Entropy Theory For The Sustainability Of Coupled Human And Natural Systems, Audrey L. Mayer, Richard P. Donovan, Christopher W. Pawlowski Sep 2014

Information And Entropy Theory For The Sustainability Of Coupled Human And Natural Systems, Audrey L. Mayer, Richard P. Donovan, Christopher W. Pawlowski

College of Forest Resources and Environmental Science Publications

For coupled human and natural systems (CHANS), sustainability can be defined operationally as a feasible, desirable set of flows (material, currency, information, energy, individuals, etc.) that can be maintained despite internal changes and changes in the environment. Sustainable development can be defined as the process by which CHANS can be moved toward sustainability. Specific indicators that give insight into the structure and behavior of feedbacks in CHANS are of particular interest because they would aid in the sustainable management of these systems through an understanding of the structures that govern system behavior. However, the use of specific feedbacks as monitoring …


Modeling Regional-Scale Wildland Fire Emissions With The Wildland Fire Emissions Information System, Nancy H. F. French, Donald Mckenzie, Tyler Erickson, Benjamin Koziol, Michael Billmire, K. A. Endsley, Naomi K. Yager Scheinerman, Liza K. Jenkins, Mary Ellen Miller, Roger Ottmar, Susan Prichard Sep 2014

Modeling Regional-Scale Wildland Fire Emissions With The Wildland Fire Emissions Information System, Nancy H. F. French, Donald Mckenzie, Tyler Erickson, Benjamin Koziol, Michael Billmire, K. A. Endsley, Naomi K. Yager Scheinerman, Liza K. Jenkins, Mary Ellen Miller, Roger Ottmar, Susan Prichard

Michigan Tech Research Institute Publications

As carbon modeling tools become more comprehensive, spatial data are needed to improve quantitative maps of carbon emissions from fire. The Wildland Fire Emissions Information System (WFEIS) provides mapped estimates of carbon emissions from historical forest fires in the United States through a web browser. WFEIS improves access to data and provides a consistent approach to estimating emissions at landscape, regional, and continental scales. The system taps into data and tools developed by the U.S. Forest Service to describe fuels, fuel loadings, and fuel consumption and merges information from the U.S. Geological Survey (USGS) and National Aeronautics and Space Administration …


Development Of Methods For Detection And Monitoring Of Fire Disturbance In The Alaskan Tundra Using A Two-Decade Long Record Of Synthetic Aperture Radar Satellite Images, Liza K. Jenkins, Laura Bourgeau-Chavez, Nancy H. F. French, Tatiana V. Loboda, Brian Thelen Jul 2014

Development Of Methods For Detection And Monitoring Of Fire Disturbance In The Alaskan Tundra Using A Two-Decade Long Record Of Synthetic Aperture Radar Satellite Images, Liza K. Jenkins, Laura Bourgeau-Chavez, Nancy H. F. French, Tatiana V. Loboda, Brian Thelen

Michigan Tech Research Institute Publications

Using the extensive archive of historical ERS-1 and -2 synthetic aperture radar (SAR) images, this analysis demonstrates that fire disturbance can be effectively detected and monitored in high northern latitudes using radar technology. A total of 392 SAR images from May to August spanning 1992–2010 were analyzed from three study fires in the Alaskan tundra. The investigated fires included the 2007 Anaktuvuk River Fire and the 1993 DCKN178 Fire on the North Slope of Alaska and the 1999 Uvgoon Creek Fire in the Noatak National Preserve. A 3 dB difference was found between burned and unburned tundra, with the best …


Management And Climate Contributions To Satellite-Derived Active Fire Trends In The Contiguous United States, Hsiao-Wen Lin, Jessica L. Mccarty, Dongdong Wang, Brendan M. Rogers, Douglas C. Morton, G. James Collatz, Yufang Jin, James T. Randerson Apr 2014

Management And Climate Contributions To Satellite-Derived Active Fire Trends In The Contiguous United States, Hsiao-Wen Lin, Jessica L. Mccarty, Dongdong Wang, Brendan M. Rogers, Douglas C. Morton, G. James Collatz, Yufang Jin, James T. Randerson

Michigan Tech Research Institute Publications

Fires in croplands, plantations, and rangelands contribute significantly to fire emissions in the United States, yet are often overshadowed by wildland fires in efforts to develop inventories or estimate responses to climate change. Here we quantified decadal trends, interannual variability, and seasonality of Terra Moderate Resolution Imaging Spectroradiometer (MODIS) observations of active fires (thermal anomalies) as a function of management type in the contiguous U.S. during 2001–2010. We used the Monitoring Trends in Burn Severity database to identify active fires within the perimeter of large wildland fires and land cover maps to identify active fires in croplands. A third class …


Melt Water Input From The Bering Glacier Watershed Into The Gulf Of Alaska, Edward G. Josberger, Robert Shuchman, Liza K. Jenkins, K. A. Endsley Feb 2014

Melt Water Input From The Bering Glacier Watershed Into The Gulf Of Alaska, Edward G. Josberger, Robert Shuchman, Liza K. Jenkins, K. A. Endsley

Michigan Tech Research Institute Publications

The annual runoff from the melting of large glaciers and snow fields along the northern perimeter of the Gulf of Alaska is a critical component of marine physical and biological systems; yet, most of this freshwater is not measured. Here we show estimates of melt for the watershed that contains the largest and longest glacier in North America, the Bering Glacier. The procedure combines in situ observations of snow and ice melt acquired by a long-term monitoring program, multispectral satellite observations, and nearby temperature measurements. The estimated melt is 40 km3 per melt season, ± 3.0 km3, observed over the …


Light Detection And Ranging (Lidar) And Multispectral Scanner (Mss) Studies Examine Coastal Environments Influenced By Mining, W. Charles Kerfoot, Martin M. Hobmeier, Foad Yousef, Sarah A. Green, Robert Regis, Colin N. Brooks, Robert Shuchman, Jamey Anderson, Molly Reif Jan 2014

Light Detection And Ranging (Lidar) And Multispectral Scanner (Mss) Studies Examine Coastal Environments Influenced By Mining, W. Charles Kerfoot, Martin M. Hobmeier, Foad Yousef, Sarah A. Green, Robert Regis, Colin N. Brooks, Robert Shuchman, Jamey Anderson, Molly Reif

Michigan Tech Research Institute Publications

There are numerous examples of past and present mine disposal into freshwater and marine coastal bays and riverine environments. Due to its high spatial resolution and extended water penetration, coastal light detection and ranging (LiDAR), coupled with multispectral scanning (MSS), has great promise for resolving disturbed shoreline features in low turbidity environments. Migrating mine tailings present serious issues for Lake Superior and coastal marine environments. Previous investigations in Lake Superior uncovered a metal-rich “halo” around the Keweenaw Peninsula, related to past copper mining practices. For over a century, waste rock migrating from shoreline tailing piles has moved along extensive stretches …


How Much Is Enough? Minimal Responses Of Water Quality And Stream Biota To Partial Retrofit Stormwater Management In A Suburban Neighborhood, Allison H. Roy, Lee K. Rhea, Audrey L. Mayer, William D. Shuster, Jake J. Beaulieu, Matthew E. Hopton, Matthew A. Morrison, Ann St. Amand Jan 2014

How Much Is Enough? Minimal Responses Of Water Quality And Stream Biota To Partial Retrofit Stormwater Management In A Suburban Neighborhood, Allison H. Roy, Lee K. Rhea, Audrey L. Mayer, William D. Shuster, Jake J. Beaulieu, Matthew E. Hopton, Matthew A. Morrison, Ann St. Amand

College of Forest Resources and Environmental Science Publications

Decentralized stormwater management approaches (e.g., biofiltration swales, pervious pavement, green roofs, rain gardens) that capture, detain, infiltrate, and filter runoff are now commonly used to minimize the impacts of stormwater runoff from impervious surfaces on aquatic ecosystems. However, there is little research on the effectiveness of retrofit, parcel-scale stormwater management practices for improving downstream aquatic ecosystem health. A reverse auction was used to encourage homeowners to mitigate stormwater on their property within the suburban, 1.8 km2 Shepherd Creek catchment in Cincinnati, Ohio (USA). In 2007–2008, 165 rain barrels and 81 rain gardens were installed on 30% of the properties …


Impacts Of Climate Change On Soil Microorganisms In Northern Hardwood Forests, Carley Jane Kratz Jan 2014

Impacts Of Climate Change On Soil Microorganisms In Northern Hardwood Forests, Carley Jane Kratz

Dissertations, Master's Theses and Master's Reports - Open

As global climate continues to change, it becomes more important to understand possible feedbacks from soils to the climate system. This dissertation focuses on soil microbial community responses to climate change factors in northern hardwood forests. Two soil warming experiments at Harvard Forest in Massachusetts, and a climate change manipulation experiment with both elevated temperature and increased moisture inputs in Michigan were sampled. The hyphal in-growth bag method was to understand how soil fungal biomass and respiration respond to climate change factors. Our results from phospholipid fatty acid (PLFA) analyses suggest that the hyphal in-growth bag method allows relatively pure …


The Study Of Agricultural Non-Point Source Pollution Control Policy System, Qin Xu Jan 2014

The Study Of Agricultural Non-Point Source Pollution Control Policy System, Qin Xu

Dissertations, Master's Theses and Master's Reports - Open

As the agricultural non-point source pollution(ANPSP) has become the most significant threat for water environmental deterioration and lake eutrophication in China, more and more scientists and technologists are focusing on the control countermeasure and pollution mechanism of agricultural non-point source pollution. The unreasonable rural production structure and limited scientific management measures are the main reasons for acute ANSPS problems in China. At present, the problem for pollution control is a lack of specific regulations, which affects the government's management efficiency.

According to these characteristics and problems, this paper puts forward some corresponding policies. The status of the agricultural non-point source …


Assessment Of Flood Risk Under Future Climate Conditions, Kaye M. Lafond Jan 2014

Assessment Of Flood Risk Under Future Climate Conditions, Kaye M. Lafond

Dissertations, Master's Theses and Master's Reports - Open

Global climate change is predicted to have impacts on the frequency and severity of flood events. In this study, output from Global Circulation Models (GCMs) for a range of possible future climate scenarios was used to force hydrologic models for four case study watersheds built using the Soil and Water Assessment Tool (SWAT). GCM output was applied with either the "delta change" method or a bias correction. Potential changes in flood risk are assessed based on modeling results and possible relationships to watershed characteristics. Differences in model outputs when using the two different methods of adjusting GCM output are also …


Volume Yields Of Smallholder Eucalyptus Grandis W. Hill Ex Maiden Stands In Eastern Paraguay, Brook F. Alloway Jan 2014

Volume Yields Of Smallholder Eucalyptus Grandis W. Hill Ex Maiden Stands In Eastern Paraguay, Brook F. Alloway

Dissertations, Master's Theses and Master's Reports - Open

Smallholders in eastern Paraguay plant small stands of Eucalyptus grandis W. Hill ex Maiden intended for sale on the local market. Smallholders have been encouraged to plant E. grandis by local forestry extension agents who offer both forestry education and incentive programs. Smallholders who practice recommended forestry techniques geared towards growing large diameter trees of good form are financially rewarded by the local markets which desire saw log quality trees. The question was posed, are smallholders engaging in recommended silvicultural practices and producing reasonable volume yields? It was hypothesized that smallholders, having received forestry education and having financial incentives from …


The Domestic Natural Gas Shortage In China, Ting Guo Jan 2014

The Domestic Natural Gas Shortage In China, Ting Guo

Dissertations, Master's Theses and Master's Reports - Open

This thesis analyzes the domestic shortage in the Chinese natural gas market. Both the domestic supply and demand of natural gas are growing fast in China. However, the supply cannot catch up with the demand. Under the present pricing mechanism, the Chinese natural gas market cannot get the equilibrium by itself. Expensive imports are inadequate to fill the increasing gap between the domestic demand and supply. Therefore, the shortage problem occurs. Since the energy gap can result in the arrested development of economics, the shortage problem need to be solved. This thesis gives three suggestions to solve the problem: the …


Electrocatalytic Processing Of Renewable Biomass-Derived Compounds For Production Of Chemicals, Fuels And Electricity, Le Xin Jan 2014

Electrocatalytic Processing Of Renewable Biomass-Derived Compounds For Production Of Chemicals, Fuels And Electricity, Le Xin

Dissertations, Master's Theses and Master's Reports - Open

The dual problems of sustaining the fast growth of human society and preserving the environment for future generations urge us to shift our focus from exploiting fossil oils to researching and developing more affordable, reliable and clean energy sources. Human beings had a long history that depended on meeting our energy demands with plant biomass, and the modern biorefinery technologies realize the effective conversion of biomass to production of transportation fuels, bulk and fine chemicals so to alleviate our reliance on fossil fuel resources of declining supply. With the aim of replacing as much non-renewable carbon from fossil oils with …


Remediation Of Tetracycline From Water Sources Using Vetiver Grass (Chrysopogon Zizanioides L. Nash) And Tetracycline-Tolerant Root-Associated Bacteria, Aparupa Sengupta Jan 2014

Remediation Of Tetracycline From Water Sources Using Vetiver Grass (Chrysopogon Zizanioides L. Nash) And Tetracycline-Tolerant Root-Associated Bacteria, Aparupa Sengupta

Dissertations, Master's Theses and Master's Reports - Open

Antibiotics are emerging contaminants worldwide. Due to insufficient policy regulations, public awareness, and the constant exposure of the environment to antibiotic sources has created a major environmental concern. Wastewater treatment plants (WWTP) are not equipped to filter-out these compounds before the discharge of the disinfected effluent into water sources (e.g., lakes and streams) and current available technologies are not equipped to remediate these compounds from environmental sources. Hence, the challenge remains to establish a biological system to remove these antibiotics from wastewater. An invitro hydroponic remediation system was developed using vetiver grass (Chrysopogon zizanioides L. Nash) to remediate tetracycline …


A Cost Analysis Of Carbon Dioxide Emission Reduction Strategies For New Plants In Michigan's Electric Power Sector, Fei Li Jan 2014

A Cost Analysis Of Carbon Dioxide Emission Reduction Strategies For New Plants In Michigan's Electric Power Sector, Fei Li

Dissertations, Master's Theses and Master's Reports - Open

This thesis attempts to find the least-cost strategy to reduce CO2 emission by replacing coal by other energy sources for electricity generation in the context of the proposed EPA’s regulation on CO2 emissions from existing coal-fired power plants. An ARIMA model is built to forecast coal consumption for electricity generation and its CO2 emissions in Michigan from 2016 to 2020. CO2 emission reduction costs are calculated under three emission reduction scenarios- reduction to 17%, 30% and 50% below the 2005 emission level. The impacts of Production Tax Credit (PTC) and the intermittency of renewable energy are …


Application Of An Imputation Method For Geospatial Inventory Of Forest Structural Attributes Across Multiple Spatial Scales In The Lake States, U.S.A., Ram K. Deo Jan 2014

Application Of An Imputation Method For Geospatial Inventory Of Forest Structural Attributes Across Multiple Spatial Scales In The Lake States, U.S.A., Ram K. Deo

Dissertations, Master's Theses and Master's Reports - Open

Credible spatial information characterizing the structure and site quality of forests is critical to sustainable forest management and planning, especially given the increasing demands and threats to forest products and services. Forest managers and planners are required to evaluate forest conditions over a broad range of scales, contingent on operational or reporting requirements. Traditionally, forest inventory estimates are generated via a design-based approach that involves generalizing sample plot measurements to characterize an unknown population across a larger area of interest. However, field plot measurements are costly and as a consequence spatial coverage is limited. Remote sensing technologies have shown remarkable …


Participant Impacts From A Participatory Water Modeling Workshop In The Sonora River Basin, Mexico, David J. Kossak Jan 2014

Participant Impacts From A Participatory Water Modeling Workshop In The Sonora River Basin, Mexico, David J. Kossak

Dissertations, Master's Theses and Master's Reports - Open

Much of the research in the field of participatory modeling (PM) has focused on the developed world. Few cases are focused on developing regions, and even fewer on Latin American developing countries. The work that has been done in Latin America has often involved water management, often specifically involving water users, and has not focused on the decision making stage of the policy cycle. Little work has been done to measure the effect PM may have on the perceptions and beliefs of decision makers. In fact, throughout the field of PM, very few attempts have been made to quantitatively measure …


The Effect Of Annealing On Amorphous Silicon Based Solar Photovoltaic Thermal System (Pv/T) And Appropriate Global Dispatch Strategies, Joseph Rozario Jan 2014

The Effect Of Annealing On Amorphous Silicon Based Solar Photovoltaic Thermal System (Pv/T) And Appropriate Global Dispatch Strategies, Joseph Rozario

Dissertations, Master's Theses and Master's Reports - Open

Previous work has shown that high-temperature short-term spike thermal annealing of hydrogenated amorphous silicon (a-Si:H) photovoltaic thermal (PVT) systems results in higher electrical energy output. The relationship between temperature and performance of a-Si:H PVT is not simple as high temperatures during thermal annealing improves the immediate electrical performance following an anneal, but during the anneal it creates a marked drop in electrical performance. In addition, the power generation of a-Si:H PVT depends on both the environmental conditions and the Staebler-Wronski Effect kinetics. In order to improve the performance of a-Si:H PVT systems further, this paper reports on the effect of …


Enzyme Optimization For Lignocellulose Hydrolysis Using Mechanistic Modeling, Adam S. Marlowe Jan 2014

Enzyme Optimization For Lignocellulose Hydrolysis Using Mechanistic Modeling, Adam S. Marlowe

Dissertations, Master's Theses and Master's Reports - Open

A novel mechanistic model for the saccharification of cellulose and hemicellulose is utilized to predict the products of hydrolysis over a range of enzyme loadings and times. The mechanistic model considers the morphology of the substrate and the kinetics of enzymes to optimize enzyme concentrations for the enzymatic hydrolysis of cellulose and hemicellulose simultaneously. Substrates are modeled based on their fraction of accessible sites, glucan content, xylan content, and degree of polymerizations. This enzyme optimization model takes into account the kinetics of six core enzymes for lignocellulose hydrolysis: endoglucanase I (EG1), cellobiohydrolase I (CBH1), cellobiohydrolase II (CBH2), and endo-xylanase (EX) …


Characterizing And Improving Production Of Fermentable Sugars And Co-Products From A Forest Product Industry Wastewater Stream, Jifei Liu Jan 2014

Characterizing And Improving Production Of Fermentable Sugars And Co-Products From A Forest Product Industry Wastewater Stream, Jifei Liu

Dissertations, Master's Theses and Master's Reports - Open

Hardboard processing wastewater was evaluated as a feedstock in a bio refinery co-located with the hardboard facility for the production of fuel grade ethanol. A thorough characterization was conducted on the wastewater and the composition changes of which during the process in the bio refinery were tracked. It was determined that the wastewater had a low solid content (1.4%), and hemicellulose was the main component in the solid, accounting for up to 70%. Acid pretreatment alone can hydrolyze the majority of the hemicellulose as well as oligomers, and over 50% of the monomer sugars generated were xylose. The percentage of …


Genetic Variation, Local Adaptation And Population Structure In North American Red Oak Species, Quercus Rubra L. And Q. Ellipsoidalis E. J. Hill, Jennifer F. Lind-Riehl Jan 2014

Genetic Variation, Local Adaptation And Population Structure In North American Red Oak Species, Quercus Rubra L. And Q. Ellipsoidalis E. J. Hill, Jennifer F. Lind-Riehl

Dissertations, Master's Theses and Master's Reports - Open

Forest trees, like oaks, rely on high levels of genetic variation to adapt to varying environmental conditions. Thus, genetic variation and its distribution are important for the long-term survival and adaptability of oak populations. Climate change is projected to lead to increased drought and fire events as well as a northward migration of tree species, including oaks. Additionally, decline in oak regeneration has become increasingly concerning since it may lead to decreased gene flow and increased inbreeding levels. This will in turn lead to lowered levels of genetic diversity, negatively affecting the growth and survival of populations. At the same …


Review Of Factors Affecting Sustainability In The Universities, Hosna Ajilian Jan 2014

Review Of Factors Affecting Sustainability In The Universities, Hosna Ajilian

Dissertations, Master's Theses and Master's Reports - Open

Purpose – The focus of this research is to find out a meaningful relationship between adopting sustainability practices and some of the characteristics of institutions of higher education (IHE). IHE can be considered as the best place to promote sustainability and develop the culture of sustainability in society. Thus, this research is conducted to help developing sustainability in IHE which have significant direct and indirect impact on society and the environment.

Design/methodology/approach – First, the sustainability letter grades were derived from “Greenreportcard.org” which have been produced based on an evaluation of each school in nine main categories including: Administration, Climate …


Denitrification In Soils: From Genes To Environmental Outcomes, Jianqiu Zheng Jan 2014

Denitrification In Soils: From Genes To Environmental Outcomes, Jianqiu Zheng

Dissertations, Master's Theses and Master's Reports - Open

Denitrification is an important process of global nitrogen cycle as it removes reactive nitrogen from the biosphere, and acts as the primary source of nitrous oxide (N2O). This thesis seeks to gain better understanding of the biogeochemistry of denitrification by investigating the process from four different aspects: genetic basis, enzymatic kinetics, environmental interactions, and environmental consequences. Laboratory and field experiments were combined with modeling efforts to unravel the complexity of denitrification process under microbiological and environmental controls.

Dynamics of denitrification products observed in laboratory experiments revealed an important role of constitutive denitrification enzymes, whose presence were further confirmed …