Agricultural emissions are the primary source of ammonia (NH 3) deposition in Rocky Mountain Nati... more Agricultural emissions are the primary source of ammonia (NH 3) deposition in Rocky Mountain National Park (RMNP), a Class I area, that is granted special air quality protections under the Clean Air Act. Between 2014 and 2016, the pilot phase of the Colorado agricultural nitrogen early warning system (CANEWS) was developed for agricultural producers to voluntarily and temporarily minimize emissions of NH 3 during periods of upslope winds. The CANEWS was created using trajectory analyses driven by outputs from an ensemble of numerical weather forecasts together with the climatological expertize of human forecasters. Here, we discuss the methods for the CANEWS and offer preliminary analyses of 33 months of the CANEWS based on atmospheric deposition data from two sites in RMNP as well as responses from agricultural producers after warnings were issued. Results showed that the CANEWS accurately predicted 6 of 9 high N deposition weeks at a lower-elevation observation site, but only 4 of 11 high N deposition weeks at a higher-elevation site. Sixty agricultural producers from 39 of Colorado's agricultural operations volunteered for the CANEWS, and a two-way line of communication between agricultural producers and scientists was formed. For each warning issued, an average of 23 producers responded to a postwarning survey. Over 75% of responding CANEWS participants altered their practices after an alert. While the current effort was insufficient to reduce atmospheric deposition, we were encouraged by the collaborative spirit between agricultural, scientific, and resource management communities. Solving a broad and complex socialecological problem requires both a technological approach, such as the CANEWS, and collaboration and trust from all participants, including agricultural producers, land managers, university researchers, and environmental agencies.
Great Plains Regional Technical Input Report, 2015
The Great Plains region experiences a wide range of extreme weather and climate events that affec... more The Great Plains region experiences a wide range of extreme weather and climate events that affect society, ecosystems, and infrastructure. The large longitudinal range from North Dakota and Montana in the north to Texas in the south contributes to the extreme range in hot and cold temperatures. Climatic phenomena that have major impacts on the Great Plains include droughts, floods, winter storms, convective storms, heat waves, cold waves, hurricanes, and sea-level rise along the coastal area of Texas. The coastal regions are affected by storms reaching in the Gulf of Mexico and convective storms across the region can lead to heavy rainfall conditions throughout the Great Plains in the summer.
Drought is a natural part of the historical climate variability in the northern Rocky Mountains a... more Drought is a natural part of the historical climate variability in the northern Rocky Mountains and high plains region of the United States. However, recent drought impacts and climate change projections have increased the need for a systematized way to document and understand drought in a manner that is meaningful to public land and resource managers. The purpose of this exploratory study was to characterize the ways in which some federal and tribal natural resource managers experienced and dealt with drought on lands managed by the U.S. Department of the Interior (DOI) and tribes in two case site examples (northwest Colorado and southwest South Dakota) that have experienced high drought exposure in the last two decades. The authors employed a social–ecological system framework, whereby key informant interviews and local and regional drought indicator data were used characterize the social and ecological factors that contribute to drought vulnerability and the ways in which drought...
Great Plains Regional Technical Input Report, 2015
Climate-ecosystem interactions and the inherent uncertainty associated with a variable and changi... more Climate-ecosystem interactions and the inherent uncertainty associated with a variable and changing climate pose a formidable threat to the region’s biological diversity and the function of aquatic and terrestrial ecosystems. Recent alterations of seasonal trends and extreme events (i.e., droughts, heat waves, floods, etc.) have affected ecosystem functions and triggered thresholds of physiological and life-cycle patterns of various species. These changes have led to changes in habitat conditions and species composition shifts. These threshold changes also have impacts on species mortality and the persistence of plant and animal populations (Allen 2010). The invasion of exotic species into terrestrial systems is likely to accelerate in response to longer growing seasons, because they will have more time to establish themselves.
Historically, pastoral people were able to more freely use the services their semi-arid and arid ... more Historically, pastoral people were able to more freely use the services their semi-arid and arid ecosystems provide, and they adapted to changes in ways that improved their well-being. More recently, their ability to adapt has been constrained due to changes from within and from outside their communities. To compare possible responses by pastoral communities, we modeled ecosystem services and tied those services to decisions that people make at the household level. We created an agent-based household model called DECUMA, joined that model with the ecosystem model SAVANNA, and applied the linked models to southeastern Kajiado District, Kenya. The structure of the new agent-based model and linkages between the models are described, and then we demonstrate the model results using a scenario that shows changes in Maasai well-being in response to drought. We then explore two additional but related scenarios, quantifying household well-being if access to a grazing reserve is lost and if access is lost but those most affected are compensated. In the second scenario, households in group ranches abutting the grazing reserve that lost access had large declines in livestock populations, less food energy from animal sources, increased livestock sales and grain purchases, and increased need for supplemental foods. Households in more distant areas showed no changes or had increases in livestock populations because their herds had fewer animals with which to compete for forage. When households neighboring the grazing reserve were compensated for the lease of the lands they had used, they prospered. We describe some benefits and limitations of the agent-based approach.
Nitrogen in the Environment: Sources, Problems and Management, 2001
This chapter discusses simulated effects of land use; soil texture; and precipitation on N gas em... more This chapter discusses simulated effects of land use; soil texture; and precipitation on N gas emissions using DAYCENT. The chapter describes the N gas flux submodel used in the DAYCENT ecosystem model and demonstrates the ability of DAYCENT to simulate the low N gas emissions observed from native soils, the intermediate emissions associated with dryland agriculture, and the high emissions observed for irrigated agricultural soils. DAYCENT has been used to compare N gas emissions from soils for native range grass, winter wheat conventional till and no till, winter wheat/corn/fallow no till, irrigated corn and irrigated silage cropping. NO x made up the majority of N gas fluxes in all cases followed by N 2 O and N 2 . Soil water inputs, tillage, timing of crop/fallow periods, and fertilizer application interact to control N gas emissions so generalizations regarding land use are difficult to make. Switching to no till without changing the winter wheat cropping schedule resulted in higher N 2 O emissions because the increased soil water content induced by no till supported higher denitrification rates. Finally, the soil water savings associated with no till also allows a reduction in the fallow period and the 3-year winter wheat rotations had lower N 2 O and NO x emissions than the 2-year winter wheat/fallow systems considered.
ABSTRACT Dramatic changes due to climate and land use dynamics in the Mongolian Plateau are affec... more ABSTRACT Dramatic changes due to climate and land use dynamics in the Mongolian Plateau are affecting ecosystem services and agro-pastoral livelihoods in Mongolia and China. Recently, evaluation of pastoral systems, where humans depend on livestock and grassland ecosystem services, have demonstrated the vulnerability of the social-ecological system to climate change. Current social-ecological changes in ecosystem services are affecting land productivity and carrying capacity, land-atmosphere interactions, water resources, and livelihood strategies. Regional dust events, changes in hydrological cycle, and land use changes contribute to changing interactions between ecosystem and landscape processes which then affect social-ecological systems. The general trend involves greater intensification of resource exploitation at the expense of traditional patterns of extensive range utilization. Thus we expect climate-land use-land cover relationships to be crucially modified by the socio-economic forces. The analysis incorporates information of the socio-economic transitions taking place in the region which affect land-use, food security, and ecosystem dynamics. The region of study extends from the Mongolian plateau in Mongolia and China to the fertile northeast China plain. Sustainability of agro-pastoral systems in the region needs to integrate the impact of climate change on ecosystem services with socio-economic changes shaping the livelihood strategies of pastoral systems in the region. Adaptation strategies which incorporate landscape management provides a potential framework to link ecosystem services across space and time more effectively to meet the needs of agro-pastoral land use, herd quality, and herder's living standards. Under appropriate adaptation strategies agro-pastoralists will have the opportunity to utilize seasonal resources and enhance their ability to process and manufacture products from the available ecosystem services in these dynamic social-ecological systems.
The impact of vegetation on the microclimate has not been adequately considered in the analysis o... more The impact of vegetation on the microclimate has not been adequately considered in the analysis of temperature forecasting and modelling. To fill part of this gap, the following study was undertaken.A daily 850–700 mb layer mean temperature, computed from the National Center for Environmental Prediction‐National Center for Atmospheric Research (NCEP‐NCAR) reanalysis, and satellite‐derived greenness values, as defined by NDVI (Normalised Difference Vegetation Index), were correlated with surface maximum and minimum temperatures at six sites in northeast Colorado for the years 1989–98. The NDVI values, representing landscape greenness, act as a proxy for latent heat partitioning via transpiration. These sites encompass a wide array of environments, from irrigated‐urban to short‐grass prairie. The explained variance (r2 value) of surface maximum and minimum temperature by only the 850–700 mb layer mean temperature was subtracted from the corresponding explained variance by the 850–700 ...
Agricultural emissions are the primary source of ammonia (NH 3) deposition in Rocky Mountain Nati... more Agricultural emissions are the primary source of ammonia (NH 3) deposition in Rocky Mountain National Park (RMNP), a Class I area, that is granted special air quality protections under the Clean Air Act. Between 2014 and 2016, the pilot phase of the Colorado agricultural nitrogen early warning system (CANEWS) was developed for agricultural producers to voluntarily and temporarily minimize emissions of NH 3 during periods of upslope winds. The CANEWS was created using trajectory analyses driven by outputs from an ensemble of numerical weather forecasts together with the climatological expertize of human forecasters. Here, we discuss the methods for the CANEWS and offer preliminary analyses of 33 months of the CANEWS based on atmospheric deposition data from two sites in RMNP as well as responses from agricultural producers after warnings were issued. Results showed that the CANEWS accurately predicted 6 of 9 high N deposition weeks at a lower-elevation observation site, but only 4 of 11 high N deposition weeks at a higher-elevation site. Sixty agricultural producers from 39 of Colorado's agricultural operations volunteered for the CANEWS, and a two-way line of communication between agricultural producers and scientists was formed. For each warning issued, an average of 23 producers responded to a postwarning survey. Over 75% of responding CANEWS participants altered their practices after an alert. While the current effort was insufficient to reduce atmospheric deposition, we were encouraged by the collaborative spirit between agricultural, scientific, and resource management communities. Solving a broad and complex socialecological problem requires both a technological approach, such as the CANEWS, and collaboration and trust from all participants, including agricultural producers, land managers, university researchers, and environmental agencies.
Great Plains Regional Technical Input Report, 2015
The Great Plains region experiences a wide range of extreme weather and climate events that affec... more The Great Plains region experiences a wide range of extreme weather and climate events that affect society, ecosystems, and infrastructure. The large longitudinal range from North Dakota and Montana in the north to Texas in the south contributes to the extreme range in hot and cold temperatures. Climatic phenomena that have major impacts on the Great Plains include droughts, floods, winter storms, convective storms, heat waves, cold waves, hurricanes, and sea-level rise along the coastal area of Texas. The coastal regions are affected by storms reaching in the Gulf of Mexico and convective storms across the region can lead to heavy rainfall conditions throughout the Great Plains in the summer.
Drought is a natural part of the historical climate variability in the northern Rocky Mountains a... more Drought is a natural part of the historical climate variability in the northern Rocky Mountains and high plains region of the United States. However, recent drought impacts and climate change projections have increased the need for a systematized way to document and understand drought in a manner that is meaningful to public land and resource managers. The purpose of this exploratory study was to characterize the ways in which some federal and tribal natural resource managers experienced and dealt with drought on lands managed by the U.S. Department of the Interior (DOI) and tribes in two case site examples (northwest Colorado and southwest South Dakota) that have experienced high drought exposure in the last two decades. The authors employed a social–ecological system framework, whereby key informant interviews and local and regional drought indicator data were used characterize the social and ecological factors that contribute to drought vulnerability and the ways in which drought...
Great Plains Regional Technical Input Report, 2015
Climate-ecosystem interactions and the inherent uncertainty associated with a variable and changi... more Climate-ecosystem interactions and the inherent uncertainty associated with a variable and changing climate pose a formidable threat to the region’s biological diversity and the function of aquatic and terrestrial ecosystems. Recent alterations of seasonal trends and extreme events (i.e., droughts, heat waves, floods, etc.) have affected ecosystem functions and triggered thresholds of physiological and life-cycle patterns of various species. These changes have led to changes in habitat conditions and species composition shifts. These threshold changes also have impacts on species mortality and the persistence of plant and animal populations (Allen 2010). The invasion of exotic species into terrestrial systems is likely to accelerate in response to longer growing seasons, because they will have more time to establish themselves.
Historically, pastoral people were able to more freely use the services their semi-arid and arid ... more Historically, pastoral people were able to more freely use the services their semi-arid and arid ecosystems provide, and they adapted to changes in ways that improved their well-being. More recently, their ability to adapt has been constrained due to changes from within and from outside their communities. To compare possible responses by pastoral communities, we modeled ecosystem services and tied those services to decisions that people make at the household level. We created an agent-based household model called DECUMA, joined that model with the ecosystem model SAVANNA, and applied the linked models to southeastern Kajiado District, Kenya. The structure of the new agent-based model and linkages between the models are described, and then we demonstrate the model results using a scenario that shows changes in Maasai well-being in response to drought. We then explore two additional but related scenarios, quantifying household well-being if access to a grazing reserve is lost and if access is lost but those most affected are compensated. In the second scenario, households in group ranches abutting the grazing reserve that lost access had large declines in livestock populations, less food energy from animal sources, increased livestock sales and grain purchases, and increased need for supplemental foods. Households in more distant areas showed no changes or had increases in livestock populations because their herds had fewer animals with which to compete for forage. When households neighboring the grazing reserve were compensated for the lease of the lands they had used, they prospered. We describe some benefits and limitations of the agent-based approach.
Nitrogen in the Environment: Sources, Problems and Management, 2001
This chapter discusses simulated effects of land use; soil texture; and precipitation on N gas em... more This chapter discusses simulated effects of land use; soil texture; and precipitation on N gas emissions using DAYCENT. The chapter describes the N gas flux submodel used in the DAYCENT ecosystem model and demonstrates the ability of DAYCENT to simulate the low N gas emissions observed from native soils, the intermediate emissions associated with dryland agriculture, and the high emissions observed for irrigated agricultural soils. DAYCENT has been used to compare N gas emissions from soils for native range grass, winter wheat conventional till and no till, winter wheat/corn/fallow no till, irrigated corn and irrigated silage cropping. NO x made up the majority of N gas fluxes in all cases followed by N 2 O and N 2 . Soil water inputs, tillage, timing of crop/fallow periods, and fertilizer application interact to control N gas emissions so generalizations regarding land use are difficult to make. Switching to no till without changing the winter wheat cropping schedule resulted in higher N 2 O emissions because the increased soil water content induced by no till supported higher denitrification rates. Finally, the soil water savings associated with no till also allows a reduction in the fallow period and the 3-year winter wheat rotations had lower N 2 O and NO x emissions than the 2-year winter wheat/fallow systems considered.
ABSTRACT Dramatic changes due to climate and land use dynamics in the Mongolian Plateau are affec... more ABSTRACT Dramatic changes due to climate and land use dynamics in the Mongolian Plateau are affecting ecosystem services and agro-pastoral livelihoods in Mongolia and China. Recently, evaluation of pastoral systems, where humans depend on livestock and grassland ecosystem services, have demonstrated the vulnerability of the social-ecological system to climate change. Current social-ecological changes in ecosystem services are affecting land productivity and carrying capacity, land-atmosphere interactions, water resources, and livelihood strategies. Regional dust events, changes in hydrological cycle, and land use changes contribute to changing interactions between ecosystem and landscape processes which then affect social-ecological systems. The general trend involves greater intensification of resource exploitation at the expense of traditional patterns of extensive range utilization. Thus we expect climate-land use-land cover relationships to be crucially modified by the socio-economic forces. The analysis incorporates information of the socio-economic transitions taking place in the region which affect land-use, food security, and ecosystem dynamics. The region of study extends from the Mongolian plateau in Mongolia and China to the fertile northeast China plain. Sustainability of agro-pastoral systems in the region needs to integrate the impact of climate change on ecosystem services with socio-economic changes shaping the livelihood strategies of pastoral systems in the region. Adaptation strategies which incorporate landscape management provides a potential framework to link ecosystem services across space and time more effectively to meet the needs of agro-pastoral land use, herd quality, and herder's living standards. Under appropriate adaptation strategies agro-pastoralists will have the opportunity to utilize seasonal resources and enhance their ability to process and manufacture products from the available ecosystem services in these dynamic social-ecological systems.
The impact of vegetation on the microclimate has not been adequately considered in the analysis o... more The impact of vegetation on the microclimate has not been adequately considered in the analysis of temperature forecasting and modelling. To fill part of this gap, the following study was undertaken.A daily 850–700 mb layer mean temperature, computed from the National Center for Environmental Prediction‐National Center for Atmospheric Research (NCEP‐NCAR) reanalysis, and satellite‐derived greenness values, as defined by NDVI (Normalised Difference Vegetation Index), were correlated with surface maximum and minimum temperatures at six sites in northeast Colorado for the years 1989–98. The NDVI values, representing landscape greenness, act as a proxy for latent heat partitioning via transpiration. These sites encompass a wide array of environments, from irrigated‐urban to short‐grass prairie. The explained variance (r2 value) of surface maximum and minimum temperature by only the 850–700 mb layer mean temperature was subtracted from the corresponding explained variance by the 850–700 ...
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