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• 1. [Article] Forest Resource Use, Land-Use, and Ecotourism in the Río Plátano Biosphere Reserve, Honduras

  The Río Pláttano Biosphere Reserve, a tropical rainforest reserve in the northeastern corner of Honduras, is home to several subsistence-based indigenous groups, including the Miskito, Pech and Garifuna, ...

  Citation × Citation Citation Abstract Copy Title: Forest Resource Use, Land-Use, and Ecotourism in the Río Plátano Biosphere Reserve, Honduras Author: Friedle, Christina Marie Year: 2005 The Río Pláttano Biosphere Reserve, a tropical rainforest reserve in the northeastern corner of Honduras, is home to several subsistence-based indigenous groups, including the Miskito, Pech and Garifuna, as well as the non-indigenous Ladinos. Communities within the reserve depend on forest resources, swidden agriculture, marine resources and/or small-scale ranching as the foundations for local economies. Regulations placed on these subsistence practices, after establishment of the biosphere reserve in 1980, have created unique and new pressures and resulted in a blend of traditional and innovative resource use. A notable result is the promotion of ecotourism as a solution for meeting the economic needs of local populations while conserving local resources. This thesis documents current resource use in the Miskito and Ladino communities of Banaka, Brans, and Fuente de Jacob, in the Río Pláttano Biosphere Reserve and the potential of ecotourism to maintain both local economies and consumption of tropical rainforest resources in these communities. Analysis suggests that a community-based approach to ecotourism can result in economic benefits and maintain local culture. This thesis documents current resource use (agricultural crops and trees, gathered and cultivated plants, tree-use, and hunting), resident perspectives on ecotourism development and industry, and provides the foundation for long-term monitoring and analysis on the effects of ecotomism on forest resource and land-use in the greater Banaka region. Title: Forest Resource Use, Land-Use, and Ecotourism in the Río Plátano Biosphere Reserve, Honduras Author: Friedle, Christina Marie Year: 2005 The Río Pláttano Biosphere Reserve, a tropical rainforest reserve in the northeastern corner of Honduras, is home to several subsistence-based indigenous groups, including the Miskito, Pech and Garifuna, as well as the non-indigenous Ladinos. Communities within the reserve depend on forest resources, swidden agriculture, marine resources and/or small-scale ranching as the foundations for local economies. Regulations placed on these subsistence practices, after establishment of the biosphere reserve in 1980, have created unique and new pressures and resulted in a blend of traditional and innovative resource use. A notable result is the promotion of ecotourism as a solution for meeting the economic needs of local populations while conserving local resources. This thesis documents current resource use in the Miskito and Ladino communities of Banaka, Brans, and Fuente de Jacob, in the Río Pláttano Biosphere Reserve and the potential of ecotourism to maintain both local economies and consumption of tropical rainforest resources in these communities. Analysis suggests that a community-based approach to ecotourism can result in economic benefits and maintain local culture. This thesis documents current resource use (agricultural crops and trees, gathered and cultivated plants, tree-use, and hunting), resident perspectives on ecotourism development and industry, and provides the foundation for long-term monitoring and analysis on the effects of ecotomism on forest resource and land-use in the greater Banaka region. Close

• 2. [Article] Determinants of the Spatial Distribution of Peri-Urban to Rural Agriculture in the United States

  Two issues are focal to the subject of the spatial distribution of crops in peri-urban zones. The first deals with developments in the fields of transportation, other technology, urbanization, and other ...

  Citation × Citation Citation Abstract Copy Title: Determinants of the Spatial Distribution of Peri-Urban to Rural Agriculture in the United States Author: Abdel-Karim, Ibrahim Amin Year: 1987 Two issues are focal to the subject of the spatial distribution of crops in peri-urban zones. The first deals with developments in the fields of transportation, other technology, urbanization, and other factors which are not only prevalent in developed world economies, but which also are thought to force the cultivation of freshly consumed agricultural commodities away from the immediate vicinity of the market center. The second issue pertains to indirectly consumed crops, which are thought to shun proximity to the market center, where land rents per unit area are characteristically high, even when conditions for productions are ideal. Traditional models have shown a zonal pattern of crop distribution in peri-urban areas. The present study sets forth two hypotheses, one pertaining to the spatial distribution of freshly consumed crops, and the other pertaining to the spatial distribution of indirectly consumed crops. It was hypothesized in the present study that freshly consumed crops will continue to be cultivated in the near vicinity of the market center due to characteristics of the crops and the urban market. It was further hypothesized that indirectly consumed crops will continue to be cultivated in the near vicinity of the market center by virtue of greater intensity of production that may be obtained through the use of the environment of designated places. In the case of both crops, the cited factors, as well as others, offset the disadvantages of higher land rent per unit area common to areas close to the market center. These offsetting factors permit agriculture to compete successfully for land in the peri-urban zone. To test these hypotheses, variables were selected to measure the influence that urbanization, transportation, other technologies, the market, the environment, and land use regulations have on agricultural siting patterns in the peri-urban zones of the "Wheat Region" of the central United States. These variables were expressed as equations and were subjected to multiple linear regression (MLR) analysis. The present findings tended to support the research hypotheses. On the basis of these findings, the present research offers a revised model of agricultural cropping patterns, one that reflects the sectoral, rather than the zonal, pattern of crop distribution in peri-urban zones. In the revised model, the mixing of different crops at various locations around the market is feasible, and low-priced grains may compete successfully for high-rent locations in the near vicinity of the urban market. The findings also show that the production of perishable crops in the iIl'.mediate vicinity of the urban market is here to stay, largely due to access to varied means of transportation as well as characteristics of the crops themselves. Furthermore, the findings show that environmental conditions influence the locating of grain production, although economic considerations were seen to supersede them, particularly at high-rent sites. Title: Determinants of the Spatial Distribution of Peri-Urban to Rural Agriculture in the United States Author: Abdel-Karim, Ibrahim Amin Year: 1987 Two issues are focal to the subject of the spatial distribution of crops in peri-urban zones. The first deals with developments in the fields of transportation, other technology, urbanization, and other factors which are not only prevalent in developed world economies, but which also are thought to force the cultivation of freshly consumed agricultural commodities away from the immediate vicinity of the market center. The second issue pertains to indirectly consumed crops, which are thought to shun proximity to the market center, where land rents per unit area are characteristically high, even when conditions for productions are ideal. Traditional models have shown a zonal pattern of crop distribution in peri-urban areas. The present study sets forth two hypotheses, one pertaining to the spatial distribution of freshly consumed crops, and the other pertaining to the spatial distribution of indirectly consumed crops. It was hypothesized in the present study that freshly consumed crops will continue to be cultivated in the near vicinity of the market center due to characteristics of the crops and the urban market. It was further hypothesized that indirectly consumed crops will continue to be cultivated in the near vicinity of the market center by virtue of greater intensity of production that may be obtained through the use of the environment of designated places. In the case of both crops, the cited factors, as well as others, offset the disadvantages of higher land rent per unit area common to areas close to the market center. These offsetting factors permit agriculture to compete successfully for land in the peri-urban zone. To test these hypotheses, variables were selected to measure the influence that urbanization, transportation, other technologies, the market, the environment, and land use regulations have on agricultural siting patterns in the peri-urban zones of the "Wheat Region" of the central United States. These variables were expressed as equations and were subjected to multiple linear regression (MLR) analysis. The present findings tended to support the research hypotheses. On the basis of these findings, the present research offers a revised model of agricultural cropping patterns, one that reflects the sectoral, rather than the zonal, pattern of crop distribution in peri-urban zones. In the revised model, the mixing of different crops at various locations around the market is feasible, and low-priced grains may compete successfully for high-rent locations in the near vicinity of the urban market. The findings also show that the production of perishable crops in the iIl'.mediate vicinity of the urban market is here to stay, largely due to access to varied means of transportation as well as characteristics of the crops themselves. Furthermore, the findings show that environmental conditions influence the locating of grain production, although economic considerations were seen to supersede them, particularly at high-rent sites. Close

• 3. [Article] Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management

  This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted ...

  Citation × Citation Citation Abstract Copy Title: Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management Author: Warren, Kelly Year: 2010 This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted geese (Anser albifrons frontalis). Ancillary questions that are considered are as follows: • If global warming is affecting these species, what is the nature of the effects? • How are the changes affecting the human environment and what can be done about these effects? In 1994, the majority of the cackler population in the Pacific Flyway began to winter in Oregon’s Willamette Valley rather than in their historical wintering areas in California’s Central Valley. In recent years, the Pacific white-fronted goose has shown a change in behavior similar to that of cacklers just before their major shift. The reasons for this shift have not been clear, though climate change, agricultural shifts, or competition with other species were thought to be possible causes. Analyses of historical breeding and wintering surveys, bird band data, harvest data, agricultural data, and climate and weather data were undertaken in the course of this thesis to see if the cause or causes could be identified. The results showed that climate and weather data, i.e. an increase in average annual temperature coupled with occasional severe winters, most closely correlated with the cacklers’ shift northward. The data comparison revealed that there is a direct relationship between cacklers and a warming shift seen on the wintering grounds. There also was a secondary correlation between the northward shift and recent changes in agricultural crops in the Willamette Valley. Substantially less data are available for white-fronts, and the relationship between their recent migration changes and climate and/or other factors is much less clear. The following recommendations for management and further study are aimed at more completely understanding the scope and causes of migration shifts and formulating well-founded management plans for geese in the Pacific Flyway: • Continue research to determine if climate change is causing changes in goose population numbers and behavior. • Expand breeding ground flight surveys to include cacklers and habitat preference to learn how habitat change on the Y-K Delta is altering cackler behavior and breeding success. • Expand radio transmitter studies and collar programs for cacklers in Oregon and Washington to verify northerly wintering shifts. • Expand collar programs for cacklers wintering in the Willamette Valley to determine if the population is continuing to shift northward. • Expand banding programs for white-fronted geese to gather more data about migration patterns. • Develop models that will allow researchers and managers to correlate migration behavior with various environmental factors including climate change in order to: 1) determine which factors are causing migration changes in specific waterfowl populations and 2) allow managers to make changes to management plans in advance of rapid changes. • Inform the public about how it can assist in collar surveys or volunteer for the U.S. Fish and Wildlife Service (USFWS). This will enable USFWS to have more concrete data and give the public an opportunity gain a greater understanding of geese and goose management. • Expand research on urban cackling geese to determine the nature and scope of their effect on the human environment and to devise management strategies. • Research energetics in migrating geese to determine whether the shift in migration patterns has its basis in climate change. • Increase data exchange and coordination among agencies. • Formulate and implement plans at the city and county levels to manage growing numbers of geese in urban areas. • Recognize and anticipate the possibility that goose populations may move into new wintering areas and formulate plans for management of those species. • Implement low cost techniques, such as more liberal bag limits and seasons, hazing, etc., to assist agricultural landowners in decreasing goose-related crop damage. Title: Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management Author: Warren, Kelly Year: 2010 This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted geese (Anser albifrons frontalis). Ancillary questions that are considered are as follows: • If global warming is affecting these species, what is the nature of the effects? • How are the changes affecting the human environment and what can be done about these effects? In 1994, the majority of the cackler population in the Pacific Flyway began to winter in Oregon’s Willamette Valley rather than in their historical wintering areas in California’s Central Valley. In recent years, the Pacific white-fronted goose has shown a change in behavior similar to that of cacklers just before their major shift. The reasons for this shift have not been clear, though climate change, agricultural shifts, or competition with other species were thought to be possible causes. Analyses of historical breeding and wintering surveys, bird band data, harvest data, agricultural data, and climate and weather data were undertaken in the course of this thesis to see if the cause or causes could be identified. The results showed that climate and weather data, i.e. an increase in average annual temperature coupled with occasional severe winters, most closely correlated with the cacklers’ shift northward. The data comparison revealed that there is a direct relationship between cacklers and a warming shift seen on the wintering grounds. There also was a secondary correlation between the northward shift and recent changes in agricultural crops in the Willamette Valley. Substantially less data are available for white-fronts, and the relationship between their recent migration changes and climate and/or other factors is much less clear. The following recommendations for management and further study are aimed at more completely understanding the scope and causes of migration shifts and formulating well-founded management plans for geese in the Pacific Flyway: • Continue research to determine if climate change is causing changes in goose population numbers and behavior. • Expand breeding ground flight surveys to include cacklers and habitat preference to learn how habitat change on the Y-K Delta is altering cackler behavior and breeding success. • Expand radio transmitter studies and collar programs for cacklers in Oregon and Washington to verify northerly wintering shifts. • Expand collar programs for cacklers wintering in the Willamette Valley to determine if the population is continuing to shift northward. • Expand banding programs for white-fronted geese to gather more data about migration patterns. • Develop models that will allow researchers and managers to correlate migration behavior with various environmental factors including climate change in order to: 1) determine which factors are causing migration changes in specific waterfowl populations and 2) allow managers to make changes to management plans in advance of rapid changes. • Inform the public about how it can assist in collar surveys or volunteer for the U.S. Fish and Wildlife Service (USFWS). This will enable USFWS to have more concrete data and give the public an opportunity gain a greater understanding of geese and goose management. • Expand research on urban cackling geese to determine the nature and scope of their effect on the human environment and to devise management strategies. • Research energetics in migrating geese to determine whether the shift in migration patterns has its basis in climate change. • Increase data exchange and coordination among agencies. • Formulate and implement plans at the city and county levels to manage growing numbers of geese in urban areas. • Recognize and anticipate the possibility that goose populations may move into new wintering areas and formulate plans for management of those species. • Implement low cost techniques, such as more liberal bag limits and seasons, hazing, etc., to assist agricultural landowners in decreasing goose-related crop damage. Close

• 4. [Article] The Theory and Practice of Genetically Engineered Crops and Agricultural Sustainability

  The development of genetically engineered (GE) crops has focused predominantly on enhancing conventional pest control approaches. Scientific assessments show that these GE crops generally deliver significant ...

  Citation × Citation Citation Abstract Copy Title: The Theory and Practice of Genetically Engineered Crops and Agricultural Sustainability Author: Ervin, David E., Glenna, Leland L., Jussaume, Raymond Adelard Year: 2011 The development of genetically engineered (GE) crops has focused predominantly on enhancing conventional pest control approaches. Scientific assessments show that these GE crops generally deliver significant economic and some environmental benefits over their conventional crop alternatives. However, emerging evidence indicates that current GE crops will not foster sustainable cropping systems unless the negative environmental and social feedback effects are properly addressed. Moreover, GE crop innovations that promote more sustainable agricultural systems will receive underinvestment by seed and chemical companies that must understandably focus on private returns for major crops. Opportunities to promote crops that convey multi-faceted benefits for the environment and the poor are foundational to a sustainable food system and should not be neglected because they also represent global public goods. In this paper, we develop a set of criteria that can guide the development of GE crops consistent with contemporary sustainable agriculture theory and practice. Based on those principles, we offer policy options and recommendations for reforming public and private R&D and commercialization processes to further the potential contributions of GE crops to sustainable agriculture. Two strategies that would help achieve this goal would be to restore the centrality of the public sector in agricultural R&D and to open the technology development process to more democratic participation by farmers and other stakeholders. Title: The Theory and Practice of Genetically Engineered Crops and Agricultural Sustainability Author: Ervin, David E., Glenna, Leland L., Jussaume, Raymond Adelard Year: 2011 The development of genetically engineered (GE) crops has focused predominantly on enhancing conventional pest control approaches. Scientific assessments show that these GE crops generally deliver significant economic and some environmental benefits over their conventional crop alternatives. However, emerging evidence indicates that current GE crops will not foster sustainable cropping systems unless the negative environmental and social feedback effects are properly addressed. Moreover, GE crop innovations that promote more sustainable agricultural systems will receive underinvestment by seed and chemical companies that must understandably focus on private returns for major crops. Opportunities to promote crops that convey multi-faceted benefits for the environment and the poor are foundational to a sustainable food system and should not be neglected because they also represent global public goods. In this paper, we develop a set of criteria that can guide the development of GE crops consistent with contemporary sustainable agriculture theory and practice. Based on those principles, we offer policy options and recommendations for reforming public and private R&D and commercialization processes to further the potential contributions of GE crops to sustainable agriculture. Two strategies that would help achieve this goal would be to restore the centrality of the public sector in agricultural R&D and to open the technology development process to more democratic participation by farmers and other stakeholders. Close

• 5. [Article] Agricultural Management Decisions Impact Isoprene Emission and Physiology of Arundo donax, an Emerging Bioenergy Crop

  Arundo donax (Giant Reed) is quickly being developed as a rapidly-growing, robust, and highly productive bioenergy crop, with large scale cultivation of this species planned for the Columbia River basin ...

  Citation × Citation Citation Abstract Copy Title: Agricultural Management Decisions Impact Isoprene Emission and Physiology of Arundo donax, an Emerging Bioenergy Crop Author: Maxfield, Jason Charles Year: 2014 Arundo donax (Giant Reed) is quickly being developed as a rapidly-growing, robust, and highly productive bioenergy crop, with large scale cultivation of this species planned for the Columbia River basin of the Pacific Northwest (USA). Despite its potential as a next generation biomass crop, relatively few studies have examined the physiological performance of A. donax under agricultural conditions. Unlike traditional crops, A. donax is known to be a high-emitter of the volatile compound isoprene, which may significantly impact regional air quality, but it has not been widely cultivated in North America and little is known about how this species will perform in the Pacific Northwest. Over two field seasons, we measured isoprene fluxes from A. donax plants in both greenhouse conditions and in an agricultural field setting under a variety of conditions and fertilizer treatments. We also measured several other attributes of A. donax productivity and leaf physiology including chlorophyll content, photosynthesis rate, stomatal conductance, specific leaf mass, water use efficiency and gas exchange. We found that A. donax physiologically performs well under cultivation in the Columbia River basin, but that it also emits isoprene at significantly higher rates than previous reports indicate. We also found that both isoprene emission and leaf physiology were highly affected by agricultural management decisions, including nitrogen and irrigation management. Our findings indicate that crop management strategies can be developed that simultaneously seek to minimize isoprene emission while maximizing biomass production in this newly emerging bioenergy crop. Title: Agricultural Management Decisions Impact Isoprene Emission and Physiology of Arundo donax, an Emerging Bioenergy Crop Author: Maxfield, Jason Charles Year: 2014 Arundo donax (Giant Reed) is quickly being developed as a rapidly-growing, robust, and highly productive bioenergy crop, with large scale cultivation of this species planned for the Columbia River basin of the Pacific Northwest (USA). Despite its potential as a next generation biomass crop, relatively few studies have examined the physiological performance of A. donax under agricultural conditions. Unlike traditional crops, A. donax is known to be a high-emitter of the volatile compound isoprene, which may significantly impact regional air quality, but it has not been widely cultivated in North America and little is known about how this species will perform in the Pacific Northwest. Over two field seasons, we measured isoprene fluxes from A. donax plants in both greenhouse conditions and in an agricultural field setting under a variety of conditions and fertilizer treatments. We also measured several other attributes of A. donax productivity and leaf physiology including chlorophyll content, photosynthesis rate, stomatal conductance, specific leaf mass, water use efficiency and gas exchange. We found that A. donax physiologically performs well under cultivation in the Columbia River basin, but that it also emits isoprene at significantly higher rates than previous reports indicate. We also found that both isoprene emission and leaf physiology were highly affected by agricultural management decisions, including nitrogen and irrigation management. Our findings indicate that crop management strategies can be developed that simultaneously seek to minimize isoprene emission while maximizing biomass production in this newly emerging bioenergy crop. Close

• 6. [Article] Agricultural Classification of Multi-Temporal MODIS Imagery in Northwest Argentina Using Kansas Crop Phenologies

  Subtropical deforestation in Latin America is thought to be driven by demand for agricultural land, particularly to grow soybeans. However, existing remote sensing methods that can differentiate crop types ...

  Citation × Citation Citation Abstract Copy Title: Agricultural Classification of Multi-Temporal MODIS Imagery in Northwest Argentina Using Kansas Crop Phenologies Author: Keifer, Jarrett Alexander Year: 2014 Subtropical deforestation in Latin America is thought to be driven by demand for agricultural land, particularly to grow soybeans. However, existing remote sensing methods that can differentiate crop types to verify this hypothesis require high spatial or spectral resolution data, or extensive ground truth information to develop training sites, none of which are freely available for much of the world. I developed a new method of crop classification based on the phenological signatures of crops extracted from multi-temporal MODIS vegetation indices. I tested and refined this method using the USDA Cropland Data Layer from Kansas, USA as a reference. I then applied the method to classify crop types for a study site in Pellegrini, Santiago Del Estero, Argentina. The results show that this method is unable to effectively separate summer crops in Pellegrini, but can differentiate summer crops and non-summer crops. Unmet assumptions about agricultural practices are primarily responsible for the ineffective summer crop classification, underlining the need for researchers to have a complete understanding of ground conditions when designing a remote sensing analysis. Title: Agricultural Classification of Multi-Temporal MODIS Imagery in Northwest Argentina Using Kansas Crop Phenologies Author: Keifer, Jarrett Alexander Year: 2014 Subtropical deforestation in Latin America is thought to be driven by demand for agricultural land, particularly to grow soybeans. However, existing remote sensing methods that can differentiate crop types to verify this hypothesis require high spatial or spectral resolution data, or extensive ground truth information to develop training sites, none of which are freely available for much of the world. I developed a new method of crop classification based on the phenological signatures of crops extracted from multi-temporal MODIS vegetation indices. I tested and refined this method using the USDA Cropland Data Layer from Kansas, USA as a reference. I then applied the method to classify crop types for a study site in Pellegrini, Santiago Del Estero, Argentina. The results show that this method is unable to effectively separate summer crops in Pellegrini, but can differentiate summer crops and non-summer crops. Unmet assumptions about agricultural practices are primarily responsible for the ineffective summer crop classification, underlining the need for researchers to have a complete understanding of ground conditions when designing a remote sensing analysis. Close

• 7. [Article] Genetically Engineering Crops for a Sustainable Agriculture

  The article examines the role of genetically engineered (GE) crops in fostering a more sustainable agriculture. An overview of the National Academy of Sciences metal study of the impacts of GE crops on ...

  Citation × Citation Citation Abstract Copy Title: Genetically Engineering Crops for a Sustainable Agriculture Author: Ervin, David E., Welsh, Rick Year: 2010 The article examines the role of genetically engineered (GE) crops in fostering a more sustainable agriculture. An overview of the National Academy of Sciences metal study of the impacts of GE crops on farm sustainability in the U.S. is given. The two types of GE crops are discussed, one which produces its own insecticide called insect resistant (IR) crops and the other is engineered to resist particular herbicides. An explanation for sustainable agriculture is also presented. Title: Genetically Engineering Crops for a Sustainable Agriculture Author: Ervin, David E., Welsh, Rick Year: 2010 The article examines the role of genetically engineered (GE) crops in fostering a more sustainable agriculture. An overview of the National Academy of Sciences metal study of the impacts of GE crops on farm sustainability in the U.S. is given. The two types of GE crops are discussed, one which produces its own insecticide called insect resistant (IR) crops and the other is engineered to resist particular herbicides. An explanation for sustainable agriculture is also presented. Close

• 8. [Article] Methane and Nitrous Oxide Emissions From Subtropical Rice Agriculture in China

  Emissions of methane and nitrous oxide, two significant greenhouse gases, were measured from rice fields at Qingyuan in Guangdong Province, China. The region has a subtropical climate which allows two ...

  Citation × Citation Citation Abstract Copy Title: Methane and Nitrous Oxide Emissions From Subtropical Rice Agriculture in China Author: Khalil, M. A. K., Shearer, Martha J., Rasmussen, R. A., Xu, Li, Liu, Jin-Luan Year: 2008 Emissions of methane and nitrous oxide, two significant greenhouse gases, were measured from rice fields at Qingyuan in Guangdong Province, China. The region has a subtropical climate which allows two crops of rice to be grown every year. The prevailing agricultural practices create a complex interaction between factors known to have a major effect on methane and nitrous oxide emissions from rice fields, namely, intermittent flooding and use of organic fertilizers. In this region, the farmers depend on nitrogen fertilizers and, at least in recent years, have only intermittently flooded their fields during the growing seasons. These factors tend to reduce methane emissions. But the rice straw and crop residues from the first crop of the year are plowed into the fields, providing a large addition of organic material under hot weather conditions favorable to quick decomposition during the second crop period. This, and the addition of farmyard manure, increases emissions of methane emissions from these fields. The results of the present study show that the effect of these competing factors and their timing lead to an average rate of emissions of 5 ± 2 and 6 ± 2 mg/m2/h from the first crops for the 2 years when measurements were taken (2003 and 2004), and 12 ± 8 and 13 ± 8 mg/m2/h from the second crop. Further, production measurements showed that during the 2 years of these experiments, the average production rates were about 27 mg/m2/h for the first crop and 22–34 mg/m2/h for the second crop, resulting in estimated oxidation rates of about 80% for the first crop and 50–60% for the second crop. The higher fluxes in the second crop therefore appear to be caused more by reduced oxidation than higher production. Nitrous oxide emissions, when they were detected, usually occurred within a few days after the application of nitrogen fertilizers. The seasonally averaged emissions were between 0.01 and 0.02 mg/m2/h except in the first year when large emissions over one short period pushed the average upward Title: Methane and Nitrous Oxide Emissions From Subtropical Rice Agriculture in China Author: Khalil, M. A. K., Shearer, Martha J., Rasmussen, R. A., Xu, Li, Liu, Jin-Luan Year: 2008 Emissions of methane and nitrous oxide, two significant greenhouse gases, were measured from rice fields at Qingyuan in Guangdong Province, China. The region has a subtropical climate which allows two crops of rice to be grown every year. The prevailing agricultural practices create a complex interaction between factors known to have a major effect on methane and nitrous oxide emissions from rice fields, namely, intermittent flooding and use of organic fertilizers. In this region, the farmers depend on nitrogen fertilizers and, at least in recent years, have only intermittently flooded their fields during the growing seasons. These factors tend to reduce methane emissions. But the rice straw and crop residues from the first crop of the year are plowed into the fields, providing a large addition of organic material under hot weather conditions favorable to quick decomposition during the second crop period. This, and the addition of farmyard manure, increases emissions of methane emissions from these fields. The results of the present study show that the effect of these competing factors and their timing lead to an average rate of emissions of 5 ± 2 and 6 ± 2 mg/m2/h from the first crops for the 2 years when measurements were taken (2003 and 2004), and 12 ± 8 and 13 ± 8 mg/m2/h from the second crop. Further, production measurements showed that during the 2 years of these experiments, the average production rates were about 27 mg/m2/h for the first crop and 22–34 mg/m2/h for the second crop, resulting in estimated oxidation rates of about 80% for the first crop and 50–60% for the second crop. The higher fluxes in the second crop therefore appear to be caused more by reduced oxidation than higher production. Nitrous oxide emissions, when they were detected, usually occurred within a few days after the application of nitrogen fertilizers. The seasonally averaged emissions were between 0.01 and 0.02 mg/m2/h except in the first year when large emissions over one short period pushed the average upward Close

• 9. [Article] Transgenic Crops: An Environmental Assessment

  The report focuses on the environmental impacts of transgenic crops, and covers biosafety regulations in the US and EU, intellectual property rights, and market and trade developments.

  Citation × Citation Citation Abstract Copy Title: Transgenic Crops: An Environmental Assessment Author: Ervin, David E., Batie, Sandra S., Welsh, Rick, Carpentier, Chantal L., Fern, Jacqueline I., Richman, Nessa J., Schulz, Mary A. Year: 2000 The report focuses on the environmental impacts of transgenic crops, and covers biosafety regulations in the US and EU, intellectual property rights, and market and trade developments. Title: Transgenic Crops: An Environmental Assessment Author: Ervin, David E., Batie, Sandra S., Welsh, Rick, Carpentier, Chantal L., Fern, Jacqueline I., Richman, Nessa J., Schulz, Mary A. Year: 2000 The report focuses on the environmental impacts of transgenic crops, and covers biosafety regulations in the US and EU, intellectual property rights, and market and trade developments. Close

• 10. [Article] Transgenic Crops and the Environment: Missing Markets and Public Roles

  The rapidity of change has left scant opportunity for investigation of the consequences of adoption of transgenic crops on long-term ecosystem or economic system functioning. Economic theory suggests that, ...

  Citation × Citation Citation Abstract Copy Title: Transgenic Crops and the Environment: Missing Markets and Public Roles Author: Ervin, David E., Batie, Sandra S. Year: 2001 The rapidity of change has left scant opportunity for investigation of the consequences of adoption of transgenic crops on long-term ecosystem or economic system functioning. Economic theory suggests that, if the "Biotechnology Revolution" is left to market forces alone, there will be neglected public goods. Theory and limited empirical evidence suggests that there are significant incentives for private firms to discount and neglect certain environmental impacts and to develop products that meet mainly the needs of those able and willing to pay. Negative distributional impacts on rural societies and economies will not normally enter the private calculus nor will the long-term problems of insect and plant resistance. Thus, there is a strong case for enhanced public roles with respect to the use of transgenic crops. The adoption of the precautionary approach in public policies addressing transgenic crops is one alternative to better reflect public concerns. Title: Transgenic Crops and the Environment: Missing Markets and Public Roles Author: Ervin, David E., Batie, Sandra S. Year: 2001 The rapidity of change has left scant opportunity for investigation of the consequences of adoption of transgenic crops on long-term ecosystem or economic system functioning. Economic theory suggests that, if the "Biotechnology Revolution" is left to market forces alone, there will be neglected public goods. Theory and limited empirical evidence suggests that there are significant incentives for private firms to discount and neglect certain environmental impacts and to develop products that meet mainly the needs of those able and willing to pay. Negative distributional impacts on rural societies and economies will not normally enter the private calculus nor will the long-term problems of insect and plant resistance. Thus, there is a strong case for enhanced public roles with respect to the use of transgenic crops. The adoption of the precautionary approach in public policies addressing transgenic crops is one alternative to better reflect public concerns. Close