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Full-Text Articles in Life Sciences

Effect Of Grazing Prairie Dog—Colonized Rangeland On Cattle Nutrition And Performance: A Progress Report, Kenneth C. Olson, Christopher Schauer, Chanda Engel, Janna J. Kincheloe, Jameson R. Brennan, Ben L. Hauptman Feb 2016

Effect Of Grazing Prairie Dog—Colonized Rangeland On Cattle Nutrition And Performance: A Progress Report, Kenneth C. Olson, Christopher Schauer, Chanda Engel, Janna J. Kincheloe, Jameson R. Brennan, Ben L. Hauptman

Natural Resource Management Faculty Publications

On the Ground

  • One objective of the ongoing Renewal on Standing Rock Reservation project is to evaluate the response of grazing steers to the level of prairie dog colonization on Northern Mixed Grass Prairie.
  • We fenced four pastures to create an increasing gradient of a proportion of the pasture area colonized by prairie dogs. Pastures are stocked with yearling steers during each growing season.
  • Comparing steer performance, Global Positioning System (GPS) locations of grazing, diet samples, and ingestive behavior at each proportion of the prairie dog colony per pasture allows prediction of the optimal proportion of colonization, which enables selection …


Probing The Past 30-Year Phenology Trend Of Us Deciduous Forests, X. Yue, N. Unger, Xiaoyang Zhang, C.S. Vogel Aug 2015

Probing The Past 30-Year Phenology Trend Of Us Deciduous Forests, X. Yue, N. Unger, Xiaoyang Zhang, C.S. Vogel

GSCE Faculty Publications

Phenology is experiencing dramatic changes over deciduous forests in the USA. Estimates of trends in phenology on the continental scale are uncertain, however, with studies failing to agree on both the magnitude and spatial distribution of trends in spring and autumn. This is due to the sparsity of in situ records, uncertainties associated with remote sensing data, and the regional focus of many studies. It has been suggested that reported trends are a result of recent temperature changes, though multiple processes are thought to be involved and the nature of the temperature forcing remains unknown. To date, no study has …


Mate Replacement And Alloparental Care In Ferruginous Hawk, Shubham Datta, Will M. Inselman, Jonathan A. Jenks, Kent Jensen, Christopher C. Swanson, Robert W. Klaver, Indrani Sasmal, Troy W. Grovenburg Jun 2015

Mate Replacement And Alloparental Care In Ferruginous Hawk, Shubham Datta, Will M. Inselman, Jonathan A. Jenks, Kent Jensen, Christopher C. Swanson, Robert W. Klaver, Indrani Sasmal, Troy W. Grovenburg

Natural Resource Management Faculty Publications

Alloparental care (i.e., care for unrelated offspring) has been documented in various avian species (Maxson 1978, Smith et al. 1996, Tella et al. 1997, Lislevand et al. 2001, Literak and Mraz 2011). A male replacement mate that encounters existing broods has options, which include alloparental care or infanticide. Infanticide may be beneficial in some species (Rohwer 1986, Kermott et al. 1990), but in long-lived avian species, like the ferruginous hawk (Buteo regalis) that do not renest within a season, infanticide might be detrimental. Adoption and rearing success likely provide direct evidence of competence of replacement mates as potential parents for …


Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaled Modis Vegetation Indices Improve Performance?, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiaoyang Zhang, Andrew Suyker, Shashi Verma, Yanmin Shuai, Elizabeth M. Middleton Jan 2015

Estimation Of Crop Gross Primary Production (Gpp): Ii. Do Scaled Modis Vegetation Indices Improve Performance?, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiaoyang Zhang, Andrew Suyker, Shashi Verma, Yanmin Shuai, Elizabeth M. Middleton

GSCE Faculty Publications

Satellite remote sensing estimates of gross primary production (GPP) have routinely been made using spectral vegetation indices (VIs) over the past two decades. The Normalized Difference Vegetation Index (NDVI), the Enhanced Vegetation Index (EVI), the green band Wide Dynamic Range Vegetation Index (WDRVIgreen), and the green band Chlorophyll Index (CIgreen) have been employed to estimate GPP under the assumption that GPP is proportional to the product of VI and photosynthetically active radiation (PAR) (where VI is one of four VIs: NDVI, EVI, WDRVIgreen, or CIgreen). However, the empirical regressions between VI*PAR and …


An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Larry Janssen, Bronc Mcmurtry, Matthew Stockton, Alexander Smart, Sharon A. Clay Jan 2015

An Economic Analysis Of High-Intensity, Short-Duration Grazing Systems In South Dakota And Nebraska, Larry Janssen, Bronc Mcmurtry, Matthew Stockton, Alexander Smart, Sharon A. Clay

Agronomy, Horticulture and Plant Science Faculty Publications

Four different grazing systems: two rotational systems, a continuous grazing system, and a modified high-intensity, short-duration (mob) system were evaluated from an economic return and risk perspective. Stocking rates and average daily gains (ADG) were obtained from 2011 – 2014 from university ranch experiments in northern Nebraska. Simulation models were used to examine net returns and risk in each system and rank systems according to risk preferences. A twice through rotational grazing system was most profitable. Mob grazing was the least preferred, although when risk aversion increased, it rose in preference. Mob grazing could be profitable if adjustments increased animal …


Effects Of Climate Change On Phenology Of Blackbirds And Orioles (Icterids) In Eastern South Dakota, Kelsey Bedford, Nicole Burkard, Brandi Crider, Emma Barnett, N. H. Troelstrup Jr. Jan 2013

Effects Of Climate Change On Phenology Of Blackbirds And Orioles (Icterids) In Eastern South Dakota, Kelsey Bedford, Nicole Burkard, Brandi Crider, Emma Barnett, N. H. Troelstrup Jr.

Oak Lake Field Station Research Publications

Birds are among the first responders to climate change, often having clearly observable phenological responses to less perceptible levels of climate shift. Declines in populations of a number of bird species have been witnessed both in the United States and abroad, with up to a 48% decline in grassland birds of the Central U.S. Understanding changes in bird abundance and distribution is essential because birds supply a wide variety of critical ecosystem services, including pollination and pest control. While the effects of climate change on many bird species’ phenology have been studied intensely, research on the family Icteridae is limited. …


Prototype For Monitoring And Forecasting Fall Foliage Coloration In Real Time From Satellite Data, Xiaoyang Zhang, Mitchell D. Goldberg, Yunyue Yu Jun 2012

Prototype For Monitoring And Forecasting Fall Foliage Coloration In Real Time From Satellite Data, Xiaoyang Zhang, Mitchell D. Goldberg, Yunyue Yu

GSCE Faculty Publications

While determining vegetation phenology from the time series of historical satellite data has been widely investigated throughout the last decade, little effort has been devoted to real-time monitoring and short-term forecasting. The latter is more important for numerical weather modeling, ecosystem forecasting, forest and crop management, and health risk warning. In this study we developed a prototype approach for the real-time monitoring and short-term forecasting of fall foliage status (including low coloration, moderate coloration, near-peak coloration, peak coloration, and post-peak coloration) using temporal satellite observations. The algorithm combined the climatology of vegetation phenology and temporally available satellite observations to establish …


Cropland Expansion Into Prairie Pothole Wetlands, 2001-2010, Carol A. Johnston Jan 2012

Cropland Expansion Into Prairie Pothole Wetlands, 2001-2010, Carol A. Johnston

Natural Resource Management Faculty Publications

No abstract provided.


Seed Abundance For Waterfowl In Wetlands Managed By The Illinois Department Of Natural Resources, Joshua D. Stafford, Aaron P. Yetter, Christopher S. Hine, Randolph S. Smith, Michelle M. Horath Jun 2011

Seed Abundance For Waterfowl In Wetlands Managed By The Illinois Department Of Natural Resources, Joshua D. Stafford, Aaron P. Yetter, Christopher S. Hine, Randolph S. Smith, Michelle M. Horath

Natural Resource Management Faculty Publications

Managed wetlands on public lands in Illinois, United States, provide foraging habitats for migrating and wintering waterfowl. However, few studies have estimated abundances of waterfowl foods in mid-migration regions of North America, yet such information is needed to inform management and conservation decision-making. During 2005– 2007, we used a multistage sampling design to estimate moist-soil plant seed production (kg/ha, dry mass) and energetic carrying capacity at sites managed by the Illinois Department of Natural Resources and modeled variation in seed biomass. Average seed biomass among all sites ranged from 1,030.0 6 64.1 (SE) kg/ha in 2005 to 501.5 6 124.1 …


Radiative Forcing Over The Conterminous United States Due To Contemporary Land Cover Use Change And Sensitivity To Snow And Interannual Albedo Variability, Christoper A. Barnes, David P. Roy Dec 2010

Radiative Forcing Over The Conterminous United States Due To Contemporary Land Cover Use Change And Sensitivity To Snow And Interannual Albedo Variability, Christoper A. Barnes, David P. Roy

GSCE Faculty Publications

Satellite‐derived land cover land use (LCLU), snow and albedo data, and incoming surface solar radiation reanalysis data were used to study the impact of LCLU change from 1973 to 2000 on surface albedo and radiative forcing for 58 ecoregions covering 69% of the conterminous United States. A net positive surface radiative forcing (i.e., warming) of 0.029 Wm−2 due to LCLU albedo change from 1973 to 2000 was estimated. The forcings for individual ecoregions were similar in magnitude to current global forcing estimates, with the most negative forcing (as low as −0.367 Wm−2) due to the transition to forest and the …


What Limits Fire? An Examination Of Driver's Of Burnt Area In Southern Africa, Sally Archibald, David P. Roy, Brian W. Van Wilgen, Robert J. Scholes Jan 2008

What Limits Fire? An Examination Of Driver's Of Burnt Area In Southern Africa, Sally Archibald, David P. Roy, Brian W. Van Wilgen, Robert J. Scholes

GSCE Faculty Publications

The factors controlling the extent of fire in Africa south of the equator were investigated using moderate resolution (500 m) satellite-derived burned area maps and spatial data on the environmental factors thought to affect burnt area. A random forest regression tree procedure was used to determine the relative importance of each factor in explaining the burned area fraction and to address hypotheses concerned with human and climatic influences on the drivers of burnt area. The model explained 68% of the variance in burnt area. Tree cover, rainfall in the previous 2 years, and rainfall seasonality were the most important predictors. …


Prairie Wetlands And Climate Change - Droughts And Ducks On The Prairies, Glenn R. Guntenspergen, W.Carter Johnson, David E. Naugle Jan 2006

Prairie Wetlands And Climate Change - Droughts And Ducks On The Prairies, Glenn R. Guntenspergen, W.Carter Johnson, David E. Naugle

Natural Resource Management Faculty Publications

The Prairie Pothole Region (PPR) contains 5-8 million small wetlands and is one of the most ecologically valuable freshwater resources of the Nation. These wetlands provide abundant ecosystem services, including groundwater recharge, water for agriculture, water purification, and recreation. The PPR is best known as the “duck factory” of North America. By some estimates, this region produces over 50% of the ducks in North America.


Fire-Induced Albedo Change And Its Radative Forcing At The Surface In Northern Austrailia, Y. Jin, David P. Roy Jul 2005

Fire-Induced Albedo Change And Its Radative Forcing At The Surface In Northern Austrailia, Y. Jin, David P. Roy

GSCE Faculty Publications

This paper investigates the impact of fire on surface albedo and the associated radiative forcing over 56% of continental Australia encompassing the fire-prone northern tropical savanna. Fire-affected areas and albedos are derived for the 2003 fire season using daily Moderate Resolution Imaging Spectroradiometer (MODIS) surface reflectance data. Near-infrared and total shortwave albedos are observed to generally decrease after fire occurrence. Regionally, the total shortwave albedo drops by an average of 0.024, with increasing reductions as the dry season progresses and larger reductions in grasslands than woody savannas. These fire-induced albedo changes exert a positive forcing at the surface that increases …


Herbicide Movement And Dissipation At Four Midwestern Sites, S. A. Clay, R. H. Dowdy, J. A. Lamb, J. L. Anderson, B. Lowery, R. E. Knight, D. E. Clay May 2000

Herbicide Movement And Dissipation At Four Midwestern Sites, S. A. Clay, R. H. Dowdy, J. A. Lamb, J. L. Anderson, B. Lowery, R. E. Knight, D. E. Clay

Agronomy, Horticulture and Plant Science Faculty Publications

This study was conducted to evaluate atrazine (2‐chloro‐4‐ethylamino‐6‐isopropyl‐1, 3, 5‐triazine) and alachlor (2‐chIoro‐N‐(methoxymethyl)acetamide) dissipation and movement to shallow aquifers across the Northern Sand Plains region of the United States. Sites were located at Minnesota on a Zimmerman fine sand, North Dakota on Hecla sandy loam, South Dakota on a Brandt silty clay loam, and Wisconsin on a Sparta sand. Herbicide concentrations were determined in soil samples taken to 90 cm four times during the growing season and water samples taken from the top one m of aquifer at least once every three months. Herbicides were detected to a …