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Full-Text Articles in Physical Sciences and Mathematics

Analysis Of Drought-Flood Abrupt Alternation Events And Their Impacts In Kenya, Betty Makena Aug 2024

Analysis Of Drought-Flood Abrupt Alternation Events And Their Impacts In Kenya, Betty Makena

School of Natural Resources: Dissertations, Theses, and Student Research

Drought-Flood Abrupt Alternation (DFAA) is a compound disaster event that refers to the abrupt shift of extreme drought events to extreme floods resulting in exacerbated impacts on already vulnerable communities and hindering their coping abilities. This study aimed to analyze drought-flood abrupt alternation events and their impacts in Kenya. The first chapter aimed to understand historical drought events in the Greater Horn of Africa and their impacts, while drawing comparisons with the recent 2020-2022 drought period, referred to as the ‘triple dip La Niña’. Datasets used in this study include the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS), Normalized …


Water Whiplash In Mediterranean Regions Of The World, Citlalli Madrigal, Rama Bedri, Thomas Piechota, Wenzhao Li, Glenn Tootle, Hesham El-Askary Jan 2024

Water Whiplash In Mediterranean Regions Of The World, Citlalli Madrigal, Rama Bedri, Thomas Piechota, Wenzhao Li, Glenn Tootle, Hesham El-Askary

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The presence of weather and water whiplash in Mediterranean regions of the world is analyzed using historical streamflow records from 1926 to 2023, depending on the region. Streamflow from the United States (California), Italy, Australia, Chile, and South Africa is analyzed using publicly available databases. Water whiplash—or the rapid shift of wet and dry periods—are compared. Wet and dry periods are defined based on annual deviations from the historical record average, and whiplash occurs when there is an abrupt change that overcomes an accommodated deficit or surplus. Of all the stations, there are more dry years (56%) than wet years …


Using Seasonal Climate Scenarios In The Forageahead Annual Forage Production Model For Early Drought Impact Assessment, M. Podebradska, B. K. Wylie, M. J. Hayes, D. J. Bathke, Y. A. Bayissa, S. P. Boyte, J. F. Brown, B. D. Wardlow Jan 2023

Using Seasonal Climate Scenarios In The Forageahead Annual Forage Production Model For Early Drought Impact Assessment, M. Podebradska, B. K. Wylie, M. J. Hayes, D. J. Bathke, Y. A. Bayissa, S. P. Boyte, J. F. Brown, B. D. Wardlow

School of Natural Resources: Faculty Publications

No abstract provided.


Evolution Of The Southwest Drought Learning Network: Collective Response To Exceptional Drought, E. Elias, B. Fuchs, J. Lisonbee, T. Bernadt, V. Martinez, T. Haigh Jan 2023

Evolution Of The Southwest Drought Learning Network: Collective Response To Exceptional Drought, E. Elias, B. Fuchs, J. Lisonbee, T. Bernadt, V. Martinez, T. Haigh

School of Natural Resources: Documents and Reviews

No abstract provided.


The Cascading And Compounding Impacts Of Drought, 2023, K. H. Smith, C. Knutson, M. Svoboda Jan 2023

The Cascading And Compounding Impacts Of Drought, 2023, K. H. Smith, C. Knutson, M. Svoboda

School of Natural Resources: Faculty Publications

No abstract provided.


Comparative Behavioral Ecotoxicology Of Inland Silverside Larvae Exposed To Pyrethroids Across A Salinity Gradient, Sara J. Hutton, Samreen Siddiqui, Emily I. Pedersen, Christopher Y. Markgraf, Amelie Segarra, Michelle L. Hladik, Richard E. Connon, Susanne M. Brander Oct 2022

Comparative Behavioral Ecotoxicology Of Inland Silverside Larvae Exposed To Pyrethroids Across A Salinity Gradient, Sara J. Hutton, Samreen Siddiqui, Emily I. Pedersen, Christopher Y. Markgraf, Amelie Segarra, Michelle L. Hladik, Richard E. Connon, Susanne M. Brander

United States Geological Survey: Staff Publications

Pyrethroids, a class of commonly used insecticides, are frequently detected in aquatic environments, including estuaries. The influence that salinity has on organism physiology and the partitioning of hydrophobic chemicals, such as pyrethroids, has driven interest in how toxicity changes in saltwater compared to freshwater. Early life exposures in fish to pyrethroids cause toxicity at environmentally relevant concentrations, which can alter behavior. Behavior is a highly sensitive endpoint that influences overall organism fitness and can be used to detect toxicity of environmentally relevant concentrations of aquatic pollutants. Inland Silversides (Menidia beryllina), a commonly used euryhaline model fish species, were exposed …


Coupling Dendrochronology And Remote Sensing Techniques To Assess The Biophysical Traits Of Juniperus Virginiana And Pinus Ponderosa Within Grassland Communities In The Semi-Arid Grasslands Of The Nebraska Sandhills, Reece Allen Jul 2022

Coupling Dendrochronology And Remote Sensing Techniques To Assess The Biophysical Traits Of Juniperus Virginiana And Pinus Ponderosa Within Grassland Communities In The Semi-Arid Grasslands Of The Nebraska Sandhills, Reece Allen

School of Natural Resources: Dissertations, Theses, and Student Research

Woody species encroachment is occurring within the sandhills region in Nebraska, primarily driven by Juniperus virginiana and Pinus ponderosa, altering ecosystems and the services they provide. Effective, low cost, and cross-scale monitoring of woody species growth and performance is necessary for integrated grassland and forest management in the face of climate variability and change. In this study, we sought to establish a relationship between remote sensing-derived vegetation indices (VIs) and dendrochronological (raw and standardized tree ring width) measurements to assess the performance of encroaching woody J. virginiana and P. ponderosa located within the Nebraska National Forest in the sandhills. …


Disturbance Reduces Fungal White-Rot Litter Mat Cover In A Wet Subtropical Forest, D. Jean Lodge, Ashley E. Van Beusekom, Grizelle González, Mareli Sánchez-Julia, Sarah Stankavich Feb 2022

Disturbance Reduces Fungal White-Rot Litter Mat Cover In A Wet Subtropical Forest, D. Jean Lodge, Ashley E. Van Beusekom, Grizelle González, Mareli Sánchez-Julia, Sarah Stankavich

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Fungi that bind leaf litter into mats and produce white-rot via degradation of lignin and other aromatic compounds influence forest nutrient cycling and soil fertility. Extent of white-rot litter mats formed by basidiomycete fungi in Puerto Rico decreased in response to disturbances—a simulated hurricane treatment executed by canopy trimming and debris addition in 2014, a drought in 2015, a treefall, and two hurricanes 10 days apart in September 2017. Percent fungal litter mat cover ranged from 0.4% after Hurricanes Irma and Maria to a high of 53% in forest with undisturbed canopy prior to the 2017 hurricanes, with means mostly …


Validity And Reliability Of Drought Reporters In Estimating Soil Water Content And Drought Impacts In Central Europe, Lenka Bartošová, Milan Fischer, Jan Balek, Monika Bláhová, Lucie Kudláčková, Filip Chuchma, Petr Hlavinka, Martin Možný, Pavel Zahradníček, Nicole Wall, Michael Hayes, Christopher Hain, Martha Anderson, Wolfgang Wagner, Zdeněk Žalud, Miroslav Trnka Jan 2022

Validity And Reliability Of Drought Reporters In Estimating Soil Water Content And Drought Impacts In Central Europe, Lenka Bartošová, Milan Fischer, Jan Balek, Monika Bláhová, Lucie Kudláčková, Filip Chuchma, Petr Hlavinka, Martin Možný, Pavel Zahradníček, Nicole Wall, Michael Hayes, Christopher Hain, Martha Anderson, Wolfgang Wagner, Zdeněk Žalud, Miroslav Trnka

School of Natural Resources: Faculty Publications

Increasing drought is considered one of the major threats associated with climate change in central Europe. To provide an objective, quantitative tool that represents current drought conditions, the Czech Drought Monitor System (CzechDM) was established in 2012. Like other drought monitoring systems worldwide, the CzechDM uses several approaches to provide drought data. However, the CzechDM is unique internationally due to its utilization of a network of voluntary reporters (farmers) who complete a weekly online questionnaire to provide information about soil water content and the impacts of drought on crop yield. In this study, the results from the questionnaires from individual …


Planning Strategies And Barriers To Achieving Local Drought Preparedness, T. Haigh, E. Wickham, S. Hamlin, C. Knutson Jan 2022

Planning Strategies And Barriers To Achieving Local Drought Preparedness, T. Haigh, E. Wickham, S. Hamlin, C. Knutson

School of Natural Resources: Faculty Publications

No abstract provided.


A Statistical Evaluation Of Earth-Observation-Based Composite Drought Indices For A Localized Assessment Of Agricultural Drought In Pakistan, C. Schwartz, W. Lee Ellenburg, V. Mishra, T. Mayer, R. Griffin, F. Qamer, M. Matin, Tsegaye Tadesse Jan 2022

A Statistical Evaluation Of Earth-Observation-Based Composite Drought Indices For A Localized Assessment Of Agricultural Drought In Pakistan, C. Schwartz, W. Lee Ellenburg, V. Mishra, T. Mayer, R. Griffin, F. Qamer, M. Matin, Tsegaye Tadesse

School of Natural Resources: Faculty Publications

No abstract provided.


When To Prepare: "Water" You Thinking About Drought?, O. G. Campbell, C. Schwartz, Deborah J. Bathke Jan 2022

When To Prepare: "Water" You Thinking About Drought?, O. G. Campbell, C. Schwartz, Deborah J. Bathke

School of Natural Resources: Faculty Publications

No abstract provided.


Polycentric Governance In Nebraska, U.S., For Ground And Surface Water, Theresa Jedd, Anthony B. Schutz, Mark Burbach Jan 2022

Polycentric Governance In Nebraska, U.S., For Ground And Surface Water, Theresa Jedd, Anthony B. Schutz, Mark Burbach

School of Natural Resources: Faculty Publications

This chapter describes the locally driven, but centrally coordinated, water governance model in Nebraska, U.S. It offers a snapshot of water resources and the importance of agriculture, then moves to the relevant political institutions in the state, and federal controls related to water quantity. The focus of the chapter is on the Nebraska Department of Natural Resources’ (NeDNR) and Natural Resources Districts’ (NRDs) management of surface and groundwater, which has some distinct and some overlapping authority. The main area of overlap is in addressing the connection between ground and surface water, particularly in situations when either or both are over …


Evidence For Irruptive Fluctuation In Axis Deer Of Hawai‘I, Steven C. Hess, Jonathan Sprague, Jacob Muise Jan 2022

Evidence For Irruptive Fluctuation In Axis Deer Of Hawai‘I, Steven C. Hess, Jonathan Sprague, Jacob Muise

United States Department of Agriculture Wildlife Services: Staff Publications

Axis deer on the Hawaiian Islands of Maui, Lāna‘i, and Moloka‘i simultaneously experienced one of the most dramatic population crashes on record in 2020-2021, which coincided with extended drought conditions and prompted an emergency declaration for these islands. This phenomenon has been anecdotally documented during previous drought events in 2011-2012, but never formally studied. Newspaper articles document abundant deer becoming a nuisance to agriculture and natural resources, and then experiencing high mortality during droughts. This phenomenon fits Caughley’s (1970) operational definition of eruptive (sic) fluctuation “…as an increase in numbers over at least two generations, followed by a marked decline.” …


California Drought Outlooks Based On Climate Change Models’ Effects On Water Availability, Lauren Lynam, Thomas Piechota Nov 2021

California Drought Outlooks Based On Climate Change Models’ Effects On Water Availability, Lauren Lynam, Thomas Piechota

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Future streamflow in California is evaluated based on eight climate projections models and the effects on water availability. The unimpaired projected streamflow for eleven California rivers, collected from Cal-Adapt, are compared with unimpaired historical flows (1950–2015) using eight climate model projections (2020–2099) identified as representative as possible future scenarios; Warm Dry RCP 4.5, Average RCP 4.5, Cool Wet RCP 4.5, Other RCP 4.5, Warm Dry RCP 8.5, Average RCP 8.5, Cool Wet RCP 8.5, and Other RCP 8.5. Projected drought deficits (or magnitudes), durations, and intensities are statistically tested against historical values to determine significance of differences between past streamflow …


An Integrated Food, Energy, And Water Nexus, Human Well-Being, And Resilience (Few-Wise) Framework: New Mexico, Kamini Yadav, Hatim M. Geli, Andres F. Cibils, Michael Hayes, Alexander Fernald, James Peach, Mohammed N. Sawalhah, Vincent C. Tidwell, Lindsay E. Johnson, Ashraf J. Zaied, Melakeneh G. Gedefaw Jun 2021

An Integrated Food, Energy, And Water Nexus, Human Well-Being, And Resilience (Few-Wise) Framework: New Mexico, Kamini Yadav, Hatim M. Geli, Andres F. Cibils, Michael Hayes, Alexander Fernald, James Peach, Mohammed N. Sawalhah, Vincent C. Tidwell, Lindsay E. Johnson, Ashraf J. Zaied, Melakeneh G. Gedefaw

School of Natural Resources: Faculty Publications

Interconnected food, energy, and water (FEW) nexus systems face many challenges to support human well-being (HWB) and maintain resilience, especially in arid and semiarid regions like New Mexico (NM), United States (US). Insufficient FEW resources, unstable economic growth due to fluctuations in prices of crude oil and natural gas, inequitable education and employment, and climate change are some of these challenges. Enhancing the resilience of such coupled socio-environmental systems depends on the efficient use of resources, improved understanding of the interlinkages across FEW system components, and adopting adaptable alternative management strategies. The goal of this study was to develop a …


Informing Drought Mitigation Policy By Estimating The Value Of Water For Crop Production, Renata Rimsaite, Justin Gibson, Nicholas Brozovic Apr 2021

Informing Drought Mitigation Policy By Estimating The Value Of Water For Crop Production, Renata Rimsaite, Justin Gibson, Nicholas Brozovic

School of Natural Resources: Faculty Publications

Farmers use irrigation to mitigate drought risk and reduce yield uncertainty. A clear understanding of the monetary value of irrigation water and how it varies across time and space can help to inform farmers and policymakers about the potential impacts of water shortages and reduce uncertainty in decision making. Here, we introduce a framework for understanding the economic value of water used to produce corn in the central High Plains region during the period 2010–2017. Our analysis uses publicly available data for corn price and for irrigated and non-irrigated yields and incorporates irrigation requirement adjustments to account for the hydrologic …


Effects Of Drought On Groundwater-Fed Lake Areas In The Nebraska Sand Hills, N. Shrestha, A. R. Mittelstet, T. E. Gilmore, V. Zlotnik, C. Neale Jan 2021

Effects Of Drought On Groundwater-Fed Lake Areas In The Nebraska Sand Hills, N. Shrestha, A. R. Mittelstet, T. E. Gilmore, V. Zlotnik, C. Neale

School of Natural Resources: Faculty Publications

No abstract provided.


Connections Between The Hydrological Cycle And Crop Yield In The Rainfed U.S. Corn Belt, Wang Zhou, Kaiyu Guan, Bin Peng, Jiancheng Shi, Chongya Jiang, Brian Wardlow, Ming Pan, John S. Kimball, Trenton Franz, Pierre Gentine, Mingzhu He, Jingwen Zhang Aug 2020

Connections Between The Hydrological Cycle And Crop Yield In The Rainfed U.S. Corn Belt, Wang Zhou, Kaiyu Guan, Bin Peng, Jiancheng Shi, Chongya Jiang, Brian Wardlow, Ming Pan, John S. Kimball, Trenton Franz, Pierre Gentine, Mingzhu He, Jingwen Zhang

School of Natural Resources: Faculty Publications

No abstract provided.


Habitat Patchiness, Ecological Connectivity And The Uneven Recovery Of Boreal Stream Ecosystems From An Experimental Drought, Amelie Truchy, Romain Sarremejane, Timo Muotka, Heikki Mykra, David G. Angeler, Kaisa Lehosmaa, Ari Huusko, Richard K. Johnson, Ryan A. Sponseller, Brendan G. Mckie Feb 2020

Habitat Patchiness, Ecological Connectivity And The Uneven Recovery Of Boreal Stream Ecosystems From An Experimental Drought, Amelie Truchy, Romain Sarremejane, Timo Muotka, Heikki Mykra, David G. Angeler, Kaisa Lehosmaa, Ari Huusko, Richard K. Johnson, Ryan A. Sponseller, Brendan G. Mckie

School of Natural Resources: Faculty Publications

Ongoing climate change is increasing the occurrence and intensity of drought episodes worldwide, including in boreal regions not previously regarded as drought prone, and where the impacts of drought remain poorly understood. Ecological connectivity is one factor that might influence community structure and ecosystem functioning post-drought, by facilitating the recovery of sensitive species via dispersal at both local (e.g. a nearby habitat patch) and regional (from other systems within the same region) scales. In an outdoor mesocosm experiment, we investigated how impacts of drought on boreal stream ecosystems are altered by the spatial arrangement of local habitat patches within stream …


Whose Ground Truth Is It? Harvesting Lessons From Missouri’S 2018 Bumper Crop Of Drought Observations, Kelly Helm Smith, Mark E. Burbach, Michael J. Hayes, A. Tyre, Patrick E. Guinan, Brian Fuchs, Tonya Haigh, Mark D. Svoboda Jan 2020

Whose Ground Truth Is It? Harvesting Lessons From Missouri’S 2018 Bumper Crop Of Drought Observations, Kelly Helm Smith, Mark E. Burbach, Michael J. Hayes, A. Tyre, Patrick E. Guinan, Brian Fuchs, Tonya Haigh, Mark D. Svoboda

School of Natural Resources: Faculty Publications

No abstract provided.


Czech Drought Monitor System For Monitoring And Forecasting Of Agricultural Drought And Drought Impacts, Miroslav Trnka, Petr Hlavinka, Martin Možný, Daniela Semerádová, Petr Štěpánek, Jan Balek, Lenka Bartošová, Pavel Zahradníček, Monika Bláhová, Petr Skalák, Aleš Farda, Michael Hayes, Mark D. Svoboda, Wolfgang Wagner, Josef Eitzinger, Milan Fischer, Zdeněk Zalud Jan 2020

Czech Drought Monitor System For Monitoring And Forecasting Of Agricultural Drought And Drought Impacts, Miroslav Trnka, Petr Hlavinka, Martin Možný, Daniela Semerádová, Petr Štěpánek, Jan Balek, Lenka Bartošová, Pavel Zahradníček, Monika Bláhová, Petr Skalák, Aleš Farda, Michael Hayes, Mark D. Svoboda, Wolfgang Wagner, Josef Eitzinger, Milan Fischer, Zdeněk Zalud

School of Natural Resources: Faculty Publications

The awareness of drought and its impacts on Central Europe increased after the significant drought episodes in 2000, 2003, 2012 and 2015, which were all estimated to have caused over 500 million Euro in damage in the Czech Republic alone. These events indicated the need for timely and highresolution monitoring tools that would enable analysing, monitoring and forecasting of drought events. Monitoring soil water availability in near real time and at high-resolution (up to 0.5 × 0.5 km for some products) helps farmers and water managers to mitigate impacts of these extreme events. The Czech Drought Monitor was developed between …


Multi-Dimensional Nature Of Drought In Abbay/Upper Blue Nile Basin And The Importance Of Regional Coordination Efforts For Mitigation, Y.A. Bayissa, S. Moges, A.M. Malesse, T. Tadesse, A.Z. Abiy Jan 2020

Multi-Dimensional Nature Of Drought In Abbay/Upper Blue Nile Basin And The Importance Of Regional Coordination Efforts For Mitigation, Y.A. Bayissa, S. Moges, A.M. Malesse, T. Tadesse, A.Z. Abiy

School of Natural Resources: Faculty Publications

No abstract provided.


Rangeland Management During Drought: Assessing Social-Ecological And Cognitive Indicators Of Ranchers’ Adaptive Capacity, Tonya Haigh Oct 2019

Rangeland Management During Drought: Assessing Social-Ecological And Cognitive Indicators Of Ranchers’ Adaptive Capacity, Tonya Haigh

School of Natural Resources: Dissertations, Theses, and Student Research

Rangeland managers face challenges to adapt to climate extremes, and research is needed on how to support their adaptive capacity for managing climate risk. This study evaluates adaptive capacity using an integrated vulnerability and resilience conceptual model and three cognitive behavioral models. Overarching research questions focus on the relationship between protective action and impacts and the best predictors of taking action in response to drought. Three studies address these questions, using quantitative data collected from two post-drought surveys of rangeland-based livestock managers in the Northern Great Plains of the U.S. The studies find evidence of the roles of social-ecological sources …


Drought Impacts Assessment In Brazil - A Remote Sensing Approach, Denis Mariano Aug 2019

Drought Impacts Assessment In Brazil - A Remote Sensing Approach, Denis Mariano

School of Natural Resources: Dissertations, Theses, and Student Research

Climate extremes are becoming more frequent in Brazil; studies project an increase in drought occurrences in many regions of the country. In the south, drought events lead to crop yield losses affecting the value chain and, therefore, the local economy. In the northeast, extended periods of drought lead to potential land degradation, affecting the livelihood and hindering local development. In the southern Amazon, an area that experienced intense land use change (LUC) in the last, the impacts are even more complex, ranging from crop yield loss and forest resilience loss, affecting ecosystem health and putting a threat on the native …


Analysis Of Gravity Recovery And Climate Experiment (Grace) Satellite-Derived Data As A Groundwater And Drought Monitoring Tool, Anthony James Mucia Jul 2018

Analysis Of Gravity Recovery And Climate Experiment (Grace) Satellite-Derived Data As A Groundwater And Drought Monitoring Tool, Anthony James Mucia

School of Natural Resources: Dissertations, Theses, and Student Research

This research compares Gravity Recovery and Climate Experiment (GRACE) groundwater storage (GWS) and root zone soil moisture (RZSM) percentiles to measured data, other drought indicators (DIs) and indices, and stakeholder observations for the purpose of assessing the feasibility and usefulness of these products to detect drought conditions. GRACE percentiles were directly compared to historic groundwater percentiles at 89 Nebraska well locations. Spatial time-series correlations over CONUS were performed between GRACE GWS and RZSM and the U.S. Drought Monitor (USDM), Standardized Precipitation Index (SPI), and soil moisture parameters from several North American Land Data Assimilation System (NLDAS) models. A survey of …


A Modis Photochemical Reflectance Index (Pri) As An Estimator Of Isoprene Emissions In A Temperate Deciduous Forest, Iolanda Filella, Chao Zhang, Roger Seco, Mark Potosnak, Alex Guenther, Thomas Karl, John A. Gamon, Stephen Pallardy, Lianhong Gu, Saewung Kim, Manuela Balzarolo, Marcos Fernandez-Martinez, Josep Penuelas Jan 2018

A Modis Photochemical Reflectance Index (Pri) As An Estimator Of Isoprene Emissions In A Temperate Deciduous Forest, Iolanda Filella, Chao Zhang, Roger Seco, Mark Potosnak, Alex Guenther, Thomas Karl, John A. Gamon, Stephen Pallardy, Lianhong Gu, Saewung Kim, Manuela Balzarolo, Marcos Fernandez-Martinez, Josep Penuelas

School of Natural Resources: Faculty Publications

The quantification of isoprene and monoterpene emissions at the ecosystem level with available models and field measurements is not entirely satisfactory. Remote-sensing techniques can extend the spatial and temporal assessment of isoprenoid fluxes. Detecting the exchange of biogenic volatile organic compounds (BVOCs) using these techniques is, however, a very challenging goal. Recent evidence suggests that a simple remotely sensed index, the photochemical reflectance index (PRI), which is indicative of light-use efficiency, relative pigment levels and excess reducing power, is a good indirect estimator of foliar isoprenoid emissions. We tested the ability of PRI to assess isoprenoid fluxes in a temperate …


Anatomy Of An Interrupted Irrigation Season: Micro-Drought At The Wind River Indian Reservation, Shannon M. Mcneeley, Cadida F. Dewes, Crystal J. Stiles, Tyler A. Beeton, Imtiaz Rangwala, Michael T. Hobbins, Cody L. Knutson Jan 2018

Anatomy Of An Interrupted Irrigation Season: Micro-Drought At The Wind River Indian Reservation, Shannon M. Mcneeley, Cadida F. Dewes, Crystal J. Stiles, Tyler A. Beeton, Imtiaz Rangwala, Michael T. Hobbins, Cody L. Knutson

School of Natural Resources: Faculty Publications

Drought is a complex phenomenon manifested through interactions between biophysical and social factors. At the Wind River Indian Reservation (WRIR) in west-central Wyoming, water shortages have become increasingly common since the turn of the 21st century. Here we discuss the 2015 water year as an exemplar year, which was characterized by wetter-than-normal conditions across the reservation and, according to the U.S. Drought Monitor, remained drought-free throughout the year. Yet parts of the reservation experienced harmful water shortages, or “microdrought” conditions, during the growing season in 2015. In this assessment of the 2015 water year at the WRIR we: (1) describe …


Semi-Arid Grassland Bird Responses To Patch-Burn Grazing And Drought, Susan K. Skagen, David J. Augustine, Justin D. Derner Jan 2017

Semi-Arid Grassland Bird Responses To Patch-Burn Grazing And Drought, Susan K. Skagen, David J. Augustine, Justin D. Derner

United States Geological Survey: Staff Publications

As grassland birds of central North America experience steep population declines with changes in land use, management of remaining tracts becomes increasingly important for population viability. The integrated use of fire and grazing may enhance vegetation heterogeneity and diversity in breeding birds, but the subsequent effects on reproduction are unknown. We examined the influence of patch-burn grazing management in shortgrass steppe in eastern Colorado on habitat use and reproductive success of 3 grassland bird species, horned lark (Eremophila alpestris), lark bunting (Calamospiza melanocorys), and McCown’s longspur (Rhynchophanes mccownii), at several spatial scales during 2011 …


Interannual Variability In Dry Mixed-Grass Prairie Yield: A Comparison Of Modis, Spot, And Field Measurements, Donald C. Wehlage, John A. Gamon, Donnette Thayer, David V. Hildebrand Jan 2016

Interannual Variability In Dry Mixed-Grass Prairie Yield: A Comparison Of Modis, Spot, And Field Measurements, Donald C. Wehlage, John A. Gamon, Donnette Thayer, David V. Hildebrand

School of Natural Resources: Faculty Publications

Remote sensing is often used to assess rangeland condition and biophysical parameters across large areas. In particular, the relationship between the Normalized Difference Vegetation Index (NDVI) and above-ground biomass can be used to assess rangeland primary productivity (seasonal carbon gain or above-ground biomass “yield”). We evaluated the NDVI–yield relationship for a southern Alberta prairie rangeland, using seasonal trends in NDVI and biomass during the 2009 and 2010 growing seasons, two years with contrasting rainfall regimes. The study compared harvested biomass and NDVI from field spectrometry to NDVI from three satellite platforms: the Aqua and Terra Moderate Resolution Imaging Spectroradiometer (MODIS) …