Progress 09/01/13 to 08/31/18
Outputs
Target Audience: Students (undergraduate and graduate students) Scientists Changes/Problems:Challenges and Solutions MSc thesis tied to objective 2 was not completed as planned due to student personal circumstances. We expect thesis completion and manuscript submission in 2019. PhD student (Elnaz), 1.5 year into program, is completing experiments for objectives 4 and 5. We anticipate dissertation completion in 2020 and report them to NIFA. Other funding sources are being used to support the PhD work. Objective 4 has been slightly modified to include 3 levels of temperature, 3 levels of moisture, 2 litter placement methods, and pulses of moisture addition. Although manuscripts were submitted in 2018, reviews and revisions took longer than expected. The papers will be shared with NIFA once they have been published. We anticipate to include the metadata with each publication. What opportunities for training and professional development has the project provided? Graduate student writing workshop (PhD student) Teaching assistant opportunity (MSc student, Sanford) R Club (PhD student) How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
The overall goal of the proposed project is to contribute to the understanding of how contrasting nutrient return patterns influence the nature and fate of the nutrient pulse at both the micro (i.e., at or near a urine/dung patch) and macro (pasture) scales in rangelands. Overall Project Accomplishment Summary: Five graduate students trained/training 11 undergraduate students, 1 postdoc; A conference symposium Two field days/stakeholder engagement; 10 presentations; Objective 1: Quantify the nutrient pulses' size and quality in relation to grazing strategies Litter deposition rate ranged from 1.7 to 14.2 kg OM ha-1 d-1. Annual litter on average of 27.7 kg N ha-1 yr-1 returned to soil while standing dead tied up 12.5 kg N ha-1 yr-1. Ultrahigh stocking densities short duration rotational grazing did not result in more litter deposition compared to more conventional low stocking density grazing management strategies. Manuscript on litter dynamic has been drafted and reviewed by co-authors Metadata on litter data (2 years) were completed MSc. Graduate Student, Aaron Shropshire completed thesis in Nov. 2018. Results: Aboveground plant production did not differ among grazing strategies Grazing strategies (low or high stocking densities) resulted in greater above ground production than non-grazed control Warm-season grasses were favored by the control and were unchanged in the grazed pastures. Soil carbon stock and bulk density did not differ among grazing management strategies. Objective 2: Measure the macro-scale spatial and temporal distribution of the nutrient pulses in relation to grazing strategies MSc. Graduate Student, Amanda Sandford (to be completed June 2019) Objective 3: Determine the micro-scale vertical and lateral transport/movement of nutrients from dung into soil by physical and biological (e.g., dung beetle) processes under varied moisture conditions, and into atmosphere as GHG emissions Overall, the study concluded that dung beetles increased GHG fluxes from dung deposits on meadows of the semi-arid Nebraska Sandhills. This study also concluded that dung beetles facilitated dung moisture and dry matter losses and subsequent increase of soil analytes in the top 10-cm soils. The results showed that dung beetles: Increased fluxes of CO2 by 0.2 g C d-1 m-2 Increased fluxes of CH4 by 0.2 mg C d-1 m-2. had no consistent on N2O fluxes, increased found by 0.4 mg N d-1 m-2 only in 2015 late in the grazing season Contributed 7 percent and 4 percent in the losses of dung moisture and dry matter, respectively Enhanced soil analytes in the top 10-cm depth of soil beneath the dung, with no effect observed in soil depth > 10 cm Objectives 4 & 5: Assess the macro-scale effect of grazing strategies on soil nitrogen mineralization P availability and carbon storage. Integrate macro-scale pattern of nutrient pulses from dung and urine, and micro-scale decomposition processes to improve existing process-based carbon and nitrogen biogeochemical models. PhD student- Elnaz Hosseini. Under field conditions in semiarid grasslands where soil-litter mixing occurs, grazing may impact the responses of soil respiration to soil moisture and temperature. The specific research questions include Which environmental variables control soil respiration? Is substrate accessibility the most important control for soil respiration? How does substrate addition, soil temperature and soil moisture interact to influence CO2 emission from grassland soil? The PhD student hypotheses have been formulated Litter addition buffers decomposers from high temperatures and low moisture conditions, thus enhancing soil CO2 emissions, Soil moisture has a larger influence during the growing season in the semi-arid grassland in the eastern Nebraska Sand Hills. A laboratory mesocosm experiment set up: soil samples collected and prepared CO2 sensors calibrated; pilot study completed to determine column size, soil volume, measurement frequency, duration of measurement, and length of incubation.
Publications
- Type:
Theses/Dissertations
Status:
Under Review
Year Published:
2018
Citation:
Grazing Strategy Effects on Utilization, Animal Performance,
Aboveground Production, Species Composition, and Soil Properties
on Nebraska Sandhills Meadow
- Type:
Journal Articles
Status:
Under Review
Year Published:
2019
Citation:
Kenneth S. Evans, Martha Mamo,* Ana Wingeyer, Walter H. Schacht, Kent M. Eskridge, Jeff Bradshaw, and Daniel Ginting. Contribution of Soil Fauna in Dung Pat Decomposition and Analyte Translocation into Grassland Soil. J. Rangeland Ecology and Management
- Type:
Journal Articles
Status:
Accepted
Year Published:
2019
Citation:
Schick, Bradley D., Guretzky, John A., Schacht, Walter, Mamo, Martha. Cattle Dung Quality, Decomposition, and Nutrient Movement into Soil Relative to Pasture Type and Time after Deposition. Crop Science
- Type:
Journal Articles
Status:
Under Review
Year Published:
2019
Citation:
Torie Lindsey, John A. Guretzky, Ana Wingeyer, Walter Schacht, Jerry Volesky, and Martha Mamo. Dynamics of litter and Nitrogen primary productivity under different Animal Stocking density in Sandhills subirrigated meadow.
- Type:
Journal Articles
Status:
Under Review
Year Published:
2019
Citation:
Kenneth S. Evans, Martha Mamo,* Ana Wingeyer, Walter H. Schacht, Kent M. Eskridge, Jeff Bradshaw, and Daniel Ginting. Dung beetles increase greenhouse gas fluxes from dung pats in a north temperate grassland
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Progress 09/01/15 to 08/31/16
Outputs
Target Audience:Scientific community Ranchers Technical service providers NRCS Grazing Coalition Students (undergraduate and graduate students) Changes/Problems:The first no-cost extension was requested and approved. This was necessary in order to complete components of objectives 2, 4, and 5. Due to existing FAA regulations and the subsequent difficulty of finding a qualified and available pilot, acquisition of images from the research site at Barta Brothers Ranch was delayed until the end of the third rotation of cattle (end of June). After finding a qualified and willing pilot, we were still challenged by the fact that the research site is four hours from Lincoln and required a long commute by the pilot. This led to a fewer number of flights being performed over the season than originally anticipated. This difficulty should be resolved by next season since FAA regulations will change at the end of August and will facilitate certification of more students as remote Pilots in Command of the sUAS. Weather (primarily rain and wind) presented some challenges in both flying the UAV and in obtaining hyperspectral proximal scans and collecting dung samples. A new multispectral sensor (Micasense RedEdge) was mounted on the UAV this year for image acquisition and we encountered some problems with the sensor which may have an effect on the completeness of coverage over a few of the pastures on some of the imaging dates. We are working with Micasense to resolve this problem. What opportunities for training and professional development has the project provided? Participation and presentations at both national and branch professional conferences (ASA-SSSA- CSA and ESA) Leading and participating in discussion in team organized symposium at the joint ESA and ASA-SSSA-CSA meeting in Minneapolis Participation and presention in weekly noon hour range meeting and discussion during the academic year; Graduate students participated in oral and/or poster presentations competition (Ken Evans 2nd place and Pat Wagner 3rd place in graduate student poster comptetition at the joint ESA and ASA-SSSA national meeting in Nov. 2015; Pat Wagner 1st place in oral competition at the ESA branch meeting in June 2016) Participation in the UNL-sponsored UAV mini-symposium, January, 2016. Attendance at UNL-sponsored Women In Science conference, August, 2016. Graduate student participation in a class geared towards preparation for taking the FAA ground school exam (to meet FAA regulations for certification to fly sUAS. How have the results been disseminated to communities of interest?Presentations at professional conferences; local meetings; and advisory board presentation. What do you plan to do during the next reporting period to accomplish the goals?Recruit the last and fourth graduate student at the PhD level to integrate grazing strategies, dung beetle, temporal and spatial distrubtion of energy in modeling C and N dynamics; Complete the peer review publications from MSc. theses/projects;
Impacts
What was accomplished under these goals?
Objective 1: Nutrient pulses' size and quality in relation to grazing strategies We examined interactive effects of grazing methods, time of grazing, sampling month, and year on mass of litter and standing dead vegetation components; monthly litter deposition rates; and annual litter, standing dead, and total dead unharvested vegetation production rates in pastures. With regard to litter deposition rates, there were grazing method x sampling month interactions that are difficult to explain and may be related to precipitation patterns. Overall, analyses showed that when cattle are stocked at the same rate grazing method does not affect the size of litter and standing dead vegetation pools nor the rate of production of these pools in pastures. In addition, new MSc. graduate student, Amanda Sandford, collected physical dung samples from 120 dung pats of differing ages (one day to fourteen days old), portions of the samples dried to obtain percent moisture values, and are currently stored frozen for further analyses of carbon, nitrogen, ammonia and nitrate content (size and quality of pulses). These same dung samples were part (subsample) of a set of 260 hyperspectral scans (Ocean Optics hyperspectral sensor) performed on site in order to eventually research the connection between spectral response (recorded by the OceanOptics) and dung characteristics. Objective 2: Macro-scale spatial and temporal distribution of the nutrient pulses and beetles in relation to grazing strategies: Mapping trampling, dung, urine at Barta and Ranches; A two chapter thesis was completed in June 2016. The project evaluated dung beetle abundance and communities in 2014 and 2015 as influenced by grazing strategies. Results showed significantly higher dung beetle diversity on pastures exposed to rotational grazing practices compared to continuous grazing or no grazing. Based on these data, rotational cattle grazing may favor the colonization of dung beetles on rangeland, regardless of stocking density. The total number of beetles collected across the three ranches over both study years was 4,192. A total of 22 different dung beetle species were found. Out of the 22 species, there were 20 new county records between Rock and Brown counties in Nebraska. In addition, dung from cattle in three different grazing practices were used to test dung beetle preference: continuous, low-stocking rotational, and high-stocking rotational. Dung beetle abundance was measured as well as the nutrient and physical properties of each dung type. Results of the study revealed no significant differences in dung beetle abundance between dung collected from each grazing practice. A journal manuscript is being prepared. New graduate student, Amanda Sanford, led the mapping at the Barta Brothers ranch using aerial platform. UAV flights were made before animals grazed the pastures; during grazing (mid point); towards end of the grazing; and after cattle were removed from the pastures. In addition, around 200 ground control/ground truth points were located in the field using a Trimble GPS unit in order to verify accuracy of an eventual classification algorithm on images obtained from the UAV. These points consisted of dung pats, bare soil patches, closely-cropped vegetation with soil exposed beneath (<50% vegetation coverage), trampled vegetation and points where both dung and soil were mixed together. Objective 3: Micro-scale transport/movement of nutrients from dung into soil and into atmosphere A three chapter thesis was completed in June 2016 evaluating the effect of dung beetle presence on the fluxes of greenhouse gasses (GHG's) from dung pats, the timing and magnitude of decomposition of dung, and subsequent fluxes of dung derived C and N into soil. Higher fluxes of GHG's from dung pats were observed. However, while higher fluxes of CO2 and N2O, and lower fluxes of CH4 due to dung pat exposure to dung beetles were observed, these effects were only significant in one experiment out of the four seasonal experiments performed. We also found that dung pat exposure to dung beetles can increase rates of mass loss in field moist dung pats, as well as rates of moisture loss. While higher concentrations of nutrients from dung pats in soil were observed, dung beetles had a minimal impact on the soil nutrient concentrations below decomposing dung pats. Two journal manuscripts are being prepared. Objective 4: to be accomplished in 2016-17 from mapping analyses. Objective 5: Integrate macro-scale pattern of nutrient pulses from dung and urine and micro scale decomposition processes to improve existing process-based CN models The DK C&N model was calibrated for the two cases of dung decomposition: with or without beetles. After calibration, the model predicted stronger C mineralization and more N released when presence of beetles than without beetles in the early moist part of the season (June). However, late season observations (July and beyond) showed the opposite trend, i.e., the presence of beetles slowed down C mineralization of the dung and likely so for N mineralization. The possible reasons for the opposite trend could be due to the relative extent of two opposite effects from beetles: acceleration of decomposition due to breakdown of large chunks of dung, and slowdown of decomposition due to drying up of dung as a result of breakdown of large chunks. In addition, a module for N leaching has been developed to account for the situation when soil moisture at lower depth of soil profile becomes higher that field capacity and nitrate concentration in soil water is significant. This part requires daily simulation of soil water dynamics with consideration of soil profile in layers. PI/CO-PIs meetings held for update and progress of project activities November 2015 April 2016 Student recruitment and training Two MSc. students successfully completed and defended their research thesis in June 2016. Ken Evans addressed microscale processes at the dung pat level, and Pat Wagner on dung beetle abundance and species. With partial support from the UNL Agricultural Research, a third MSc. graduate student, Amanda Sanford, was recruited and joined in Januray 2016. Amanda is working on spatial and temporal distribution of dung and litter using UAV and remote sensing technology and is being supervised by Drs Mamo and Volesky. Amanda has taken the FAA pilot short course to obtain certification to fly UAV. In addition the team was awarded funding of $92,000 to support a PhD student to develop an integrated model. The student will be supervised by Drs. Yang and Mamo and will join in January 2017. Three undergraduate students were mentored and assisted in field work, lab analyses, and data entry activities (Samantha Teten, freshman; Matt Judkins, senior; and Julio Rangel, exchange student from Brazil). These students also participated in project and/or group meetings. Collaboration developed with CALMIT and potential collaboration under discussion for soil biology & health initiative The team is interested in expanding reserch questions related to grazing management strategies, particularly understanding how root death from grazing and trampling and manure deposition affects soil biology-plant feedbacks. In Nov. 2015, Dr Wingeyer, Mamo, and Schatman had an initial meeting to discuss potential collaboration in November 2015. Collaboration with UNL's CALMIT (Center for Advanced Land Management and Imaging Technologies) to utilize Trimble technology for GPS location of ground truth points and the Ocean Optics hyperspectral sensor (proximal, backpack-mounted) for advanced non-invasive spectral analysis of dung pats across space and time. New graduate student, Amanda Sanford, is working closely with CALMIT.
Publications
- Type:
Theses/Dissertations
Status:
Accepted
Year Published:
2016
Citation:
EFFECT OF DUNG BEETLES ON DUNG DECOMPOSITION AND NUTRIENT
CYCLING IN A NEBRASKA RANGELAND. MSc. thesis of Kenneth Evans - Advisor Martha Mamo
- Type:
Theses/Dissertations
Status:
Accepted
Year Published:
2016
Citation:
INFLUENCE OF CATTLE GRAZING PRACTICES ON DUNG BEETLE (COLEOPTERA: SCARABAEOIDEA) COMMUNITIES IN THE SANDHILL RANGELANDS OF CENTRAL NEBRASKA. MSc. thesis of Patrick Wagner- Advisor Jeff Bradshaw
- Type:
Theses/Dissertations
Status:
Accepted
Year Published:
2016
Citation:
VEGETATION COVER AND CATTLE RESPONSES TO GRAZING STRATEGIES ON NEBRASKA SANDHILLS. MSc. thesis of Torie Lindsey. AdvisorS Walter Schacht and Jerry Volesky.
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2015
Citation:
Symposium-Organized by Bradshaw, Mamo, and Wingeyer
-Partnering to Understand Complexity: Biogeochemical Cycles in Agricultural Systems. 8 papers presented. ASA-CSA-SSSA Annual Meeting. Minneapolis, MN.
https://scisoc.confex.com/scisoc/2015am/webprogram/Session14488.html
1) Nitrogen Use Efficiency and Cycling in Pastures Managed with Reduced Nitrogen Inputs.John A. Guretzky, Walter Schacht, Terry Klopfenstein, ; Anita Wingeyer
2) Dung Decomposition As a Function of Cattle Diet.Brad Schick
3) Grazing Management Effect on Micro- and Macro- Scale Fate of Carbon and Nitrogen in Rangelands.Ana B. Wingeyer, Martha Mamo, Jeffrey Bradshaw, Walter Schacht, Jerry Volesky, John A. Guretzky, Richard B. Ferguson, Haishun Yang, Kent Eskridge, Sean Whipple,Karla Jenkins.
4) Fate of Nutrient Inputs from Dung Pats.Kenneth Evans, Anita Wingeyer, Martha Mamo, Walter Schacht, Pamela J Sutton, Kent Eskridge.
5)Influence of Cattle Grazing Practices on Dung Beetle Communities.
Patrick Wagner
6)Using Model Simulation to Quantify the Role of Dung Beetle in Dung C and N Decomposition.Haishun Yang, Martha Mamo, Anita Wingeyer, Walter Schacht, Jeff Bradshaw, Kenneth Evans, Kent Eskridge.
- Type:
Conference Papers and Presentations
Status:
Accepted
Year Published:
2016
Citation:
ESA NCB Meeting June 2016. Two presentation on Cattle Grazing Practices Influence Dung Beetle Communities on Rangeland
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Progress 09/01/14 to 08/31/15
Outputs
Target Audience:Scientific community Ranchers Technical service providers NRCS Grazing Coalition Students (undergraduate and graduate students) Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?Participation and presentations at professional conferences for scientists and students (undergduate and graduate) Nebraska Range Short Course (one graduate student participant) Oganize a symposium at the ASA-SSSA-CSA annual meeting in Minneapolis, MN; How have the results been disseminated to communities of interest?Presentations at field days to ranchers and NRCS personnel What do you plan to do during the next reporting period to accomplish the goals?Recruit 3rd graduate student for aerial UAV mapping and data processing component of grazing strategies plus modelling; complete two MSc. theses with associated publications; begin the process of formulating a new model that combines the strength of different modeling approaches for more robust simulation of C and N decomposition processes for grazing rangeland; develop extension circular for dissemination;
Impacts
What was accomplished under these goals?
Objective 1: Nutrient pulses' size and quality in relation to grazing strategies In 2014, we completed the first year of data collection on litter deposition rates and total annual production of standing dead vegetation and litter pools. We measured litter deposition at the same locations seven times from 19 May 2014 to 15 March 2015. From these data, we computed litter deposition rates by dividing by the number of days between sampling intervals. After the first year of data collection, we did not observe differences among cattle stocking (i.e., grazing) methods on litter deposition rates. Rates at which dead plant material was detached from live vegetation and deposited on the soil surface, regardless of whether vegetation was left standing or trampled, was similar in pastures with 4-paddock, once-over, cattle rotations as pastures managed with mob stocking. Main effects of sampling date and stocking method by sampling date interactions were important. Highest litter deposition rates coincided with the 60-day grazing period between mid-June and mid-August. Total annual production (April 2014-March 2015) of standing dead vegetation and litter also was similar between stocking methods, averaging 1333 and 2631 kg ha-1 (dry matter basis), respectively. Objective 2: Macro-scale spatial and temporal distribution of the nutrient pulses and beetles in relation to grazing strategies: Mapping trampling, dung, urine at Barta and Ranches; We collected samples of dung beetles using pitfall traps at three different ranches; Barta Brothers and two collaborating ranches (Mr. Rick Marshall and Mr. Randall Shinn). Trapping for dung beetles ran for the duration of the grazing season (May/June - August/September). Results indicated significantly higher dung beetle diversity in treatments where rotational grazing was practiced compared to continuous grazing or no grazing. Also, upland mob grazing at the Marshall ranch yielded higher diversity than meadow grazing overall. The total number of beetles collected on the three ranches were 760 individuals at Barta Brothers, 528 at Rick Marshall, and 565 at Randall Shinn. A grand total of 1,853 dung beetles were collected in 2014. Across the three ranches, a total of 20 different dung beetle species were found. Out of the 20 species, there were 16 new records for Rock and Brown counties in Nebraska. We are in the process of calibrating UAV taken images with ground GPS coordinates. We have thus far refined methods to delineate pats using floor tiles as reference points on the ground. We have accomplished the following: -Pilot flight at Mead NE ARDC grazing study (20%, 40%, and 60% utilization)- May 13 2015 -Georeferenced pats and non pats area for calibration with aerial map and for subsequent dung pat sampling for CN analyses (June 17) -Several images taken at Barta Brothers ranch on mob grazing and four pasture once over treatments (June 17) Objective 3: Micro-scale transport/movement of nutrients from dung into soil and into atmosphere A four-month long dung decomposition experiment at Barta Brothers Ranch in Summer of 2014 was conducted. The treatments included homogenized 20-cm dung pat covered with mesh to exclude dung beetles, exposed dung pat, and control (no dung pat). The treatments were arranged in a repeated measurement RCB with 8 blocks and replicated during the grazing season (sequential June and July experiment). Gas samples were taken at 1, 2, 3, 7, 10, 14, 21, 28, and 56 days after dung placement. Soil samples at 0-10 and 10-20 cm depths taken below dung pat at 1, 3, 7, 14, 28, and 56 days after dung placement. In 2014, there was no consistent trend in GHG flux when pat was covered to exclude dung beetles and flux was similar between NO BEETLE and BEETLE TRTs. Ammonium and nitrate in soil were higher under dung pat as expected. However, ammonium level in dung pat exposed to dung beetle was higher compared to no dung beetle exposure. Objective 4: to be accomplished in 2016 Objective 5: Integrate macro-scale pattern of nutrient pulses from dung and urine and micro scale decomposition processes to improve existing process-based CN models We have set up the two models we proposed to use in the project: the DK C&N model and the DNDC model. Preliminary runs have been made using both model to test their sensitivities of C and N mineralization to environmental, soil and management variables, including temperature, C:N ratio of incoming organic substrates, time of substrate incorporation, and soil pH and Eh. Temperature is found be one of the key environmental variables that drive the intensity of decomposition. We are currently collecting and processing the data from 2014 and 2015 and calibrating the two models for the specific conditions of the experiment. Quarterly meetings held for update and progress of project activities August 29 2014 December 18 2014 March 19 2015 June 30 2015 (included field day) Organizing Special Session at joint 2015 ESA-ASA meeting Title: Symposium--Partnering to Understand Complexity: Biogeochemical Cycles in Agricultural Systems Organizers: Ana B. Wingeyer , Martha Mamo and Jeff Bradshaw Presiders: Jeff Bradshaw and Martha Mamo Lead Community Sponsor: Cosponsor: Soil & Water Management & Conservation Community Cosponsor: Animal Agriculture and the Environment Community, Soil Carbon and Greenhouse Gas Emissions Community Format: Oral Symposium Keywords: Session Description: The increasing food demand and the emerging environmental challenges, including nutrient loads in ground and surface water and greenhouse gas emissions, call for fine tuning of nutrient management in agricultural systems. Grazing and manure additions add to the complexity of biogeochemical cycles in agricultural systems, by impacting soil, water, air and biota processes and relationships. This special session is focused on the partnering for solutions across societies to study the complexity of nutrient cycling in agricultural systems by fostering of interdisciplinary research approaches. The session aims to bring 3-4 presentations per project that will showcase how the interdisciplinary approach contributes to the synergy in science and the results across disciplines. Student recruitment and training Two MSc. students are completing (May 2016) their projects, Ken Evans on objective 3 microscale processes at the dung pat level, and Pat Wagner on dung beetle abundance and species. We are in the process of recruiting a third graduate student with partial support from UNL to address components of objectives 1, 2, 4, and 5. In addition, a total of seven undergraduate students (Beckmann, Franck, Siel, Brown, Hatch, Judkins, Zhang), have participated in project activities including four completing special supporting research projects as follows: Matt Judkins - 2014-15. Assessing dung beetle colonization in the decomposition of dung pat (presented at Section SMR and National SRM meetings) Jenna Beckman - 2014. Evaluating methods for dung pat moisture and dry matter determination Erin Hatch - 2014- Evaluation of insect exclosures' effect on dung pat decomposition and nutrient movement Zhang Yu-tong - 2015. (Northwest China University Intern). 2015. Soil microbial community structure under dung with or without dung beetle exposures using genomic tools New collaboration developed with animal gut microbiologist Understanding how soil microbes interact with environmental conditions and affect GHG flux dynamics in managed pastures. Overarching goal is to evaluate how moisture (wetness or drought), dung pats interacts to effect microbial community structure and associated GHG flux.Preliminary work being conducted to assess how age of dung pat affect microbial community both in the early and late grazing season.
Publications
- Type:
Conference Papers and Presentations
Status:
Published
Year Published:
2014
Citation:
Evans, K., Wingeyer, A., Mamo, M., Sutton, P., Bradshaw, J., Eskridge, K., Beckmann, J., Hatch, E., ASA-CSA-SSSA Annual Meeting, Long Beach, "Fate of C and N Inputs from Dung Pats into Soil", Research/Creative Activity, Conference. (November 2014).
Evans, K., Wingeyer, A., Mamo, M., Schacht, W., Sutton, P., Eskridge, K., ASA-CSA-SSSA Annual Meeting, Long Beach, "Greenhouse Gas Emissions from Dung Pats". (November 2014).
Guretzky, J., Wingeyer, A., Schacht, W., Volesky, J., Mamo, M., Stockton, M., ASA, CSSA, and SSSA International Annual Meetings, Crop Science Society of America, Long Beach, CA, "Demonstrating Mob Grazing Impacts in the Nebraska Sandhills - Lessons Learned", Research/Creative Activity, Conference, International, Accepted. (November 4, 2014).
Mamo, M., Bradshaw, J., Ferguson, R., Eskridge, K., Guretzky, J., Jenkins, K., Schacht, W., Volesky, J., Whipple, S., Wingeyer, A., Yang, H., NIFA Project Director Meeting, USDA-AFRI, DC, "Grazing Management Effect on Micro- and Macro- Scale Fate of C and N in Rangelands", Research/Creative Activity, Conference. (October 2014).
Judkins, M., Mamo, M., Wingeyer, A., Bradshaw, J., Evans, K., and Schacht. Society of Range Management Annual Meeting, Sacramento, "Assessing Cattle Dung Colonization by Dung Beetle". (February 2015).
Judkins, M., Mamo, M., Wingeyer, A., Bradshaw, J., Evans, K., and Schacht. Nebraska Section of Society of Range Management, North Platte, "Assessing Cattle Dung Colonization by Dung Beetle". (October 2014).
Mamo, M., Bradshaw, J., Ferguson, R., Eskridge, K., Evans, K, Guretzky, J., Jenkins, K., Schacht, W., Volesky, J., Wagner, P., Whipple, S., Wingeyer, A., Yang, H., NIFA Project Director Meeting, USDA-AFRI, DC, "Grazing Management Effect on Micro- and Macro- Scale Fate of C and N in Rangelands", Research/Creative Activity, Conference. (July 2015).
- Type:
Websites
Status:
Published
Year Published:
2014
Citation:
http://agronomy.unl.edu/grazingmanagement
http://agronomy.unl.edu/mobgrazing
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