Biodiversity management of fens and fen meadows by grazing, cutting and burning

USGS Publications Warehouse

Middleton, B.A.; Holsten, B.; Van Diggelen, R.

2006-01-01

Question: Can the biodiversity of fens in Europe and North America be maintained through the use of grazing (especially cattle grazing), fire, and/or cutting? Location: European and North American fens. Methods: This paper is a review of the literature on the effects of grazing, fire and cutting on fens, to explore the relationship between management and biodiversity in fens. Results: A reduction of cattle grazing, mowing and burning in fens has led to a reduction in biodiversity in fens. The vegetation of abandoned fens shifts to trees and shrubs after 10-15 years, which shade the smaller and rarer species of these wetlands. While careful use of fire is used to manage fens in North America, it is not widely used in European fens, perhaps because the peat of drained fens may catch fire. Cattle grazing cannot be considered a natural disturbance in North America, since cattle did not evolve on that continent. In Europe, cattle do not generally graze in unaltered fens, but they do use slightly drained fen meadows. Conclusions: Three approaches have been used to control the dominance of tall woody and herbaceous species in abandoned fens, including the re-introduction of cattle, mowing, and burning. Overgrazing results in a permanent reduction in biodiversity, therefore cattle re-introduction must be approached cautiously. In Europe, but not in North America, mowing has been an important management tool, and mowing has been successful in maintaining species richness, particularly in fens that have been mowed annually for centuries. Fire has been the most common and successful management tool in North America although it is not effective in removing shrubs that have become large. Because the problems and solutions are similar, the literature of both European and North American fen management can be analyzed to better assess the management of fens on both continents. Many management questions require further study and these are listed in the paper. ?? IAVS; Opulus Press.

FORAGES AND PASTURES SYMPOSIUM: Improving soil health and productivity on grasslands using managed grazing of livestock.

PubMed

Russell, J R; Bisinger, J J

2015-06-01

Beyond grazing, managed grasslands provide ecological services that may offer economic incentives for multifunctional use. Increasing biodiversity of plant communities may maximize net primary production by optimizing utilization of available light, water, and nutrient resources; enhance production stability in response to climatic stress; reduce invasion of exotic species; increase soil OM; reduce nutrient leaching or loading in surface runoff; and provide wildlife habitat. Strategically managed grazing may increase biodiversity of cool-season pastures by creating disturbance in plant communities through herbivory, treading, nutrient cycling, and plant seed dispersal. Soil OM will increase carbon and nutrient sequestration and water-holding capacity of soils and is greater in grazed pastures than nongrazed grasslands or land used for row crop or hay production. However, results of studies evaluating the effects of different grazing management systems on soil OM are limited and inconsistent. Although roots and organic residues of pasture forages create soil macropores that reduce soil compaction, grazing has increased soil bulk density or penetration resistance regardless of stocking rates or systems. But the effects of the duration of grazing and rest periods on soil compaction need further evaluation. Because vegetative cover dissipates the energy of falling raindrops and plant stems and tillers reduce the rate of surface water flow, managing grazing to maintain adequate vegetative cover will minimize the effects of treading on water infiltration in both upland and riparian locations. Through increased diversity of the plant community with alterations of habitat structure, grazing systems can be developed that enhance habitat for wildlife and insect pollinators. Although grazing management may enhance the ecological services provided by grasslands, environmental responses are controlled by variations in climate, soil, landscape position, and plant community

Grazing-induced BVOC fluxes from a managed grassland

NASA Astrophysics Data System (ADS)

Mozaffar, Ahsan; Schoon, Niels; Bachy, Aurelie; Digrado, Anthony; Heinesch, Bernard; Aubinet, Marc; Fauconnier, Marie-laure; Delaplace, Pierre; Dujardin, Patrick; Amelynck, Crist

2017-04-01

Grassland ecosystems cover one fourth of the Earth's land surface and are both sources and sinks of Biogenic Volatile Organic Compounds (BVOCs) which play an important role in atmospheric chemistry and air pollution. The use of grassland for cattle breeding is a common practice in many parts of the world. As it has been widely demonstrated that plants emit large bursts of BVOCs when they are mechanically damaged, grass tearing and trampling during grazing are expected to induce large BVOC emissions as well. Nevertheless, to the best of our knowledge, no study has been performed on BVOC fluxes from grazed grassland yet. Therefore investigations were performed using automated dynamic chambers in a managed grassland in Belgium over the 2015 and 2016 growing season. BVOC fluxes, together with carbon dioxide (CO2) and water vapor (H2O) fluxes from grazed and undisturbed grassland were followed simultaneously using PTR-MS (Proton Transfer Reaction-Mass Spectrometry) and a LI-840 non-dispersive IR gas analyzer. In addition, air in the chamber was sampled occasionally for GC-MS (Gas Chromatography-Mass Spectrometry) analysis to assist compound identification. Significant differences between grazed and undisturbed grassland patches were observed in terms of BVOC, CO2 and H2O vapor fluxes. Grazing by cows was found to result in enhanced emissions of several BVOCs such as methanol, acetaldehyde, acetone, acetic acid and Green Leaf Volatiles (GLVs), and induced BVOC emissions generally lasted for around 5 days following a grazing event. Quantitative data on the impact of grazing on BVOC, CO2 and H2O exchange between grassland and the atmosphere will be presented, and correlations between BVOC fluxes and environmental conditions will be discussed.

Effect of agro-ecological zone and grazing system on incidence of East Coast Fever in calves in Mbale and Sironko Districts of Eastern Uganda.

PubMed

Rubaire-Akiiki, Christopher M; Okello-Onen, Joseph; Musunga, David; Kabagambe, Edmond K; Vaarst, Mettee; Okello, David; Opolot, Charles; Bisagaya, A; Okori, C; Bisagati, C; Ongyera, S; Mwayi, M T

2006-08-17

Between May 2002 and February 2003 a longitudinal survey was carried out in Mbale and Sironko Districts of Eastern Uganda to determine the influence of agro-ecological zones (AEZ) and grazing systems on tick infestation patterns and incidence of East Coast Fever (ECF) in bovine calves. The study area was stratified into AEZ (lowland, midland and upland) and grazing systems {zero grazing (ZG), restricted-outdoor grazing (ROG) and communal grazing (CG)}, whose strata had previously been shown to influence the prevalence of ECF, babesiosis and anaplasmosis. One hundred and eighty-five smallholder dairy farms with a total of 198 calves of both sexes, between the ages of 1 day and 6 weeks, were purposively selected from the AEZ-grazing system strata. Nine dynamic cohorts (11-51 calves in each) of these calves were examined and sampled monthly. Ticks infesting the calves were counted from one side of the animal body and categorized into the different species, sex and feeding status. Sera were collected at recruitment and monthly thereafter and antibodies against Theileria parva, T. mutans, Babesia bigemina, B. bovis and Anaplasma marginale were measured using ELISA. Tick challenge (total and specific) varied with AEZ and grazing system. The risk of infection with T. parva was higher in the lowland zone compared to the upland zone (hazard ratio (HR)=2.59; 95% CI: 1.00-6.34). The risk of infection with T. parva was higher in the CG system than the ZG system (HR=10.00; 95% CI: 3.61-27.92). The incidence risk for sero-conversion, over the 10 months study period, was 62, 16 and 9% in the lowland, midland and upland zones, respectively. Ninety-eight percent of the calves in lowland-CG stratum sero-converted by the age of 6 months, while 56 and 8% did so in the lowland-ROG and the lowland-ZG stratum, respectively. The results of this study show the need to consider farm circumstances and the variation in ECF risk, both spatially and temporally when designing control strategies

Strategic grazing management towards sustainable intensification at tropical pasture-based dairy systems.

PubMed

Congio, Guilhermo F S; Batalha, Camila D A; Chiavegato, Marília B; Berndt, Alexandre; Oliveira, Patrícia P A; Frighetto, Rosa T S; Maxwell, Thomas M R; Gregorini, Pablo; Da Silva, Sila C

2018-05-01

Agricultural systems are responsible for environmental impacts that can be mitigated through the adoption of more sustainable principles. Our objective was to investigate the influence of two pre-grazing targets (95% and maximum canopy light interception during pasture regrowth; LI 95% and LI Max , respectively) on sward structure and herbage nutritive value of elephant grass cv. Cameroon, and dry matter intake (DMI), milk yield, stocking rate, enteric methane (CH 4 ) emissions by Holstein × Jersey dairy cows. We hypothesized that grazing strategies modifying the sward structure of elephant grass (Pennisetum purpureum Schum.) improves nutritive value of herbage, increasing DMI and reducing intensity of enteric CH 4 emissions, providing environmental and productivity benefits to tropical pasture-based dairy systems. Results indicated that pre-sward surface height was greater for LI Max (≈135 cm) than LI 95% (≈100 cm) and can be used as a reliable field guide for monitoring sward structure. Grazing management based on LI 95% criteria improved herbage nutritive value and grazing efficiency, allowing greater DMI, milk yield and stocking rate by dairy cows. Daily enteric CH 4 emission was not affected; however, cows grazing elephant grass at LI 95% were more efficient and emitted 21% less CH 4 /kg of milk yield and 18% less CH 4 /kg of DMI. The 51% increase in milk yield per hectare overcame the 29% increase in enteric CH 4 emissions per hectare in LI 95% grazing management. Thereby the same resource allocation resulted in a 16% mitigation of the main greenhouse gas from pasture-based dairy systems. Overall, strategic grazing management is an environmental friendly practice that improves use efficiency of allocated resources through optimization of processes evolving plant, ruminant and their interface, and enhances milk production efficiency of tropical pasture-based systems. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of buffer strips and grazing management on soil loss from pastures

USDA-ARS?s Scientific Manuscript database

Intensive grazing pressure can cause soil erosion from pastures causing increased sediment loading to aquatic systems. The objectives of this work were to determine the long-term effects of grazing management and buffer strips on soil erosion from pastures fertilized with broiler litter. Field stud...

Long-term effects of grazing management and buffer strips on soil erosion from pastures

USDA-ARS?s Scientific Manuscript database

High grazing pressure can lead to soil erosion in pastures by compacting soil and increasing runoff and sediment delivery to waterways. Limited information exists on the effects of grazing management and best management practices (BMPs), such as buffer strips, on soil erosion from pastures. The obje...

Post-fire grazing management in the Great Basin

USDA-ARS?s Scientific Manuscript database

Increasing wildfire size and frequency in the Great Basin call for post-fire grazing management practices that ensure sagebrush steppe communities are productive and resilient to disturbances such as drought and species invasions. We provide guidelines for maintaining productive sagebrush steppe co...

Towards evenly distributed grazing patterns: including social context in sheep management strategies.

PubMed

di Virgilio, Agustina; Morales, Juan Manuel

2016-01-01

Background. A large proportion of natural grasslands around the world is exposed to overgrazing resulting in land degradation and biodiversity loss. Although there is an increasing effort in the promotion of sustainable livestock management, rangeland degradation still occurs because animals' foraging behaviour is highly selective at different spatial scales. The assessment of the ecological mechanisms modulating the spatial distribution of grazing and how to control it has critical implications for long term conservation of resources and the sustainability of livestock production. Considering the relevance of social interactions on animals' space use patterns, our aim was to explore the potential effects of including animals' social context into management strategies using domestic sheep grazing in rangelands as case study. Methods. We used GPS data from 19 Merino sheep (approximately 10% of the flock) grazing on three different paddocks (with sizes from 80 to 1000 Ha) during a year, to estimate resource selection functions of sheep grazing in flocks of different levels of heterogeneity. We assessed the effects of sheep class (i.e., ewes, wethers, and hoggets), age, body condition and time since release on habitat selection patterns. Results. We found that social rank was reflected on sheep habitat use, where dominant individuals (i.e., reproductive females) used more intensively the most preferred areas and low-ranked (i.e., yearlings) used less preferred areas. Our results showed that when sheep grazed on more heterogeneous flocks, grazing patterns were more evenly distributed at all the paddocks considered in this study. On the other hand, when high-ranked individuals were removed from the flock, low-ranked sheep shifted their selection patterns by increasing the use of the most preferred areas and strongly avoided to use less preferred sites (i.e., a highly selective grazing behaviour). Discussion. Although homogenization and segregation of flocks by classes

Towards evenly distributed grazing patterns: including social context in sheep management strategies

PubMed Central

Morales, Juan Manuel

2016-01-01

Background. A large proportion of natural grasslands around the world is exposed to overgrazing resulting in land degradation and biodiversity loss. Although there is an increasing effort in the promotion of sustainable livestock management, rangeland degradation still occurs because animals’ foraging behaviour is highly selective at different spatial scales. The assessment of the ecological mechanisms modulating the spatial distribution of grazing and how to control it has critical implications for long term conservation of resources and the sustainability of livestock production. Considering the relevance of social interactions on animals’ space use patterns, our aim was to explore the potential effects of including animals’ social context into management strategies using domestic sheep grazing in rangelands as case study. Methods. We used GPS data from 19 Merino sheep (approximately 10% of the flock) grazing on three different paddocks (with sizes from 80 to 1000 Ha) during a year, to estimate resource selection functions of sheep grazing in flocks of different levels of heterogeneity. We assessed the effects of sheep class (i.e., ewes, wethers, and hoggets), age, body condition and time since release on habitat selection patterns. Results. We found that social rank was reflected on sheep habitat use, where dominant individuals (i.e., reproductive females) used more intensively the most preferred areas and low-ranked (i.e., yearlings) used less preferred areas. Our results showed that when sheep grazed on more heterogeneous flocks, grazing patterns were more evenly distributed at all the paddocks considered in this study. On the other hand, when high-ranked individuals were removed from the flock, low-ranked sheep shifted their selection patterns by increasing the use of the most preferred areas and strongly avoided to use less preferred sites (i.e., a highly selective grazing behaviour). Discussion. Although homogenization and segregation of flocks by

Effects of previous grazing nutrition and management on feedlot performance of cattle.

PubMed

Drouillard, J S; Kuhl, G L

1999-01-01

Management strategies designed to improve grazing animal performance can influence feedlot performance and carcass traits both positively and negatively. In spite of the economic relevance of potential interactions between grazing and finishing performance, controlled experiments evaluating integrated production systems are limited in number. Effects of grazing treatments can result from, or be overshadowed by, changes in gut fill, thus making it difficult to assign precise costs to different phases of production. Published reports have considered the effects of stocking rate, duration of grazing, forage characteristics, supplementation, and growth-promoting implants on subsequent finishing performance. Improvements in cattle performance attributed to changes in stocking rate generally have been neutral to positive with respect to effects on finishing performance. Comparisons among forages have led to the suggestion that forage species may contribute to differences in gastrointestinal fill of grazing cattle, thereby influencing gain and efficiency during the subsequent finishing phase. Creep-feeding suckling calves generally has increased preweaning performance but has had relatively little influence on performance during the subsequent finishing phase. Grain supplementation of stocker cattle during the grazing period has improved grazing performance, but effects on subsequent feedlot performance have been inconsistent. Potential carryover effects from protein and mineral supplementation also have been inconclusive. Lack of congruence among studies is puzzling but may be the consequence of highly varied production systems, differences in experimental procedures, and changes in gut fill or mass of internal organs. Based on the studies reviewed, the expression or absence of compensatory growth during the finishing phase appears to be related to the nutritional quality of forages utilized in the grazing period, with higher quality forages tending to yield greater

Equine Grazing in Managed Subalpine Wetlands: Effects on Arthropods and Plant Structure as a Function of Habitat

NASA Astrophysics Data System (ADS)

Holmquist, Jeffrey G.; Schmidt-Gengenbach, Jutta; Haultain, Sylvia A.

2013-12-01

Grazing management necessarily emphasizes the most spatially extensive vegetation assemblages, but landscapes are mosaics, often with more mesic vegetation types embedded within a matrix of drier vegetation. Our primary objective was to contrast effects of equine grazing on both subalpine vegetation structure and associated arthropods in a drier reed grass ( Calamagrostis muiriana) dominated habitat versus a wetter, more productive sedge habitat ( Carex utriculata). A second objective was to compare reed grass and sedge as habitats for fauna, irrespective of grazing. All work was done in Sequoia National Park (CA, USA), where detailed, long-term records of stock management were available. We sampled paired grazed and control wet meadows that contained both habitats. There were moderate negative effects of grazing on vegetation, and effects were greater in sedge than in reed grass. Conversely, negative grazing effects on arthropods, albeit limited, were greater in the drier reed grass, possibly due to microhabitat differences. The differing effects on plants and animals as a function of habitat emphasize the importance of considering both flora and fauna, as well as multiple habitat types, when making management decisions. Sedge supported twice the overall arthropod abundance of reed grass as well as greater diversity; hemipteran and dipteran taxa were particularly abundant in sedge. Given the greater grazing effects on sedge vegetation, greater habitat provision for terrestrial arthropods, and value as aquatic arthropod habitat, the wetter sedge assemblage is worthy of additional consideration by managers when planning for grazing and other aspects of land usage.

Livestock grazing for management of reclaimed land at Navajo Mine: Animal response

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gamble, D.C.; Gadzia, K.L.; Raisbeck, M.F.

1997-12-31

Livestock responses dining grazing of reclaimed land were monitored at the Navajo Mine since 1994. The Navajo Mine Grazing Management Program (GNP) began in 1991 to prepare for bond release and return of reclaimed land to the Navajo Nation by demonstrating the ability of the land to sustain the post-mining land use of livestock grazing. Local Navajos, whose livestock are used in the GMP, are interested in the ability of the land to sustain their livestock. Sustainable livestock grazing implies the ability of animals to thrive, successfully reproduce and maintain the health of the land. Daily care and monitoring ofmore » livestock health was carried out by herders hired by the mining company. General animal health parameters including blood selenium levels were monitored quarterly. Livestock responses to grazing reclaimed land have been largely positive. Cows have produced healthy offspring and owners indicate satisfaction with calf size, and overall performance of the cows. Selenium and other blood testing parameters indicate no adverse effect on animal health to date. Hazards associated with reclamation and ongoing mining activities are important considerations for lands being reclaimed for livestock grazing as a post-mining land use and must be monitored carefully during any grazing program. Preliminary results indicate that planned grazing by cattle on reclaimed land at Navajo Mine is feasible and does not adversely affect animal health.« less

Grazing management for healthy watersheds

Treesearch

Karl Wood

2008-01-01

(Please note, this is an abstract only) New Mexico was historically grazed by many native and introduced ungulates, often called wildlife. Their distribution was limited especially in deserts until domestic animals were introduced and drinking water was provided. Plants respond to grazing with little resistance (black grama), to great resistance (blue grama), and to...

Sound management may sequester methane in grazed rangeland ecosystems

USDA-ARS?s Scientific Manuscript database

Considering their contribution to global warming, the sources and sinks of methane (CH4) should be accounted when undertaking a greenhouse gas inventory for grazed rangeland ecosystems. The aim of this study was to evaluate the mitigation potential of current ecological management programs implement...

Soil organic carbon stock in grasslands: Effects of inorganic fertilizers, liming and grazing in different climate settings.

PubMed

Eze, Samuel; Palmer, Sheila M; Chapman, Pippa J

2018-06-12

Grasslands store about 34% of the global terrestrial carbon (C) and are vital for the provision of various ecosystem services such as forage and climate regulation. About 89% of this grassland C is stored in the soil and is affected by management activities but the effects of these management activities on C storage under different climate settings are not known. In this study, we synthesized the effects of fertilizer (nitrogen and phosphorus) application, liming and grazing regime on the stock of SOC in global grasslands, under different site specific climatic settings using a meta-analysis of 341 datasets. We found an overall significant reduction (-8.5%) in the stock of SOC in global managed grasslands, mainly attributable to grazing (-15.0%), and only partially attenuated by fertilizer addition (+6.7%) and liming (+5.8%), indicating that management to improve biomass production does not contribute sufficient organic matter to replace that lost by direct removal by animals. Management activities had the greatest effect in the tropics (-22.4%) due primarily to heavy grazing, and the least effect in the temperate zone (-4.5%). The negative management effect reduced significantly with increasing mean annual temperature and mean annual precipitation in the temperate zone, suggesting that temperate grassland soils are potential C sinks in the face of climate change. For a sustainable management of grasslands that will provide adequate forage for livestock and mitigate climate change through C sequestration, we recommend that future tropical grassland management policies should focus on reducing the intensity of grazing. Also, to verify our findings for temperate grasslands and to better inform land management policy, future research should focus on the impacts of the projected climate change on net greenhouse gas exchange and potential climate feedbacks. Copyright © 2018 Elsevier Ltd. All rights reserved.

Economic modelling of grazing management against gastrointestinal nematodes in dairy cattle.

PubMed

van der Voort, M; Van Meensel, J; Lauwers, L; de Haan, M H A; Evers, A G; Van Huylenbroeck, G; Charlier, J

2017-03-15

Grazing management (GM) interventions, such as reducing the grazing time or mowing pasture before grazing, have been proposed to limit the exposure to gastrointestinal (GI) nematode infections in grazed livestock. However, the farm-level economic effects of these interventions have not yet been assessed. In this paper, the economic effects of three GM interventions in adult dairy cattle were modelled for a set of Flemish farms: later turnout on pasture (GM1), earlier housing near the end of the grazing season (GM2), and reducing the daily grazing time (GM3). Farm accountancy data were linked to Ostertagia ostertagi bulk tank milk ELISA results and GM data for 137 farms. The economic effects of the GM interventions were investigated through a combination of efficiency analysis and a whole-farm simulation model. Modelling of GM1, GM2 and GM3 resulted in a marginal economic effect of € 8.36, € -9.05 and € -53.37 per cow per year, respectively. The results suggest that the dairy farms can improve their economic performance by postponing the turnout date, but that advancing the housing date or reducing daily grazing time mostly leads to a lower net economic farm performance. Overall, the GM interventions resulted in a higher technical efficiency and milk production but these benefits were offset by increased feed costs as a result of higher maintenance and cultivation costs. Because the results differed highly between farms, GM interventions need to be evaluated at the individual level for appropriate decision support. Copyright © 2017 Elsevier B.V. All rights reserved.

43 CFR 4130.5 - Free-use grazing permits.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Free-use grazing permits. 4130.5 Section... MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE OF ALASKA Authorizing Grazing Use § 4130.5 Free-use grazing permits. (a) A free-use grazing permit shall be issued to...

43 CFR 4130.5 - Free-use grazing permits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Free-use grazing permits. 4130.5 Section... MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE OF ALASKA Authorizing Grazing Use § 4130.5 Free-use grazing permits. (a) A free-use grazing permit shall be issued to...

43 CFR 4130.5 - Free-use grazing permits.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Free-use grazing permits. 4130.5 Section... MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE OF ALASKA Authorizing Grazing Use § 4130.5 Free-use grazing permits. (a) A free-use grazing permit shall be issued to...

43 CFR 4130.5 - Free-use grazing permits.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Free-use grazing permits. 4130.5 Section... MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE OF ALASKA Authorizing Grazing Use § 4130.5 Free-use grazing permits. (a) A free-use grazing permit shall be issued to...

Critical review of the impacts of grazing intensity on soil organic carbon storage and other soil quality indicators in extensively managed grasslands.

PubMed

Abdalla, M; Hastings, A; Chadwick, D R; Jones, D L; Evans, C D; Jones, M B; Rees, R M; Smith, P

2018-02-01

Livestock grazing intensity (GI) is thought to have a major impact on soil organic carbon (SOC) storage and soil quality indicators in grassland agroecosystems. To critically investigate this, we conducted a global review and meta-analysis of 83 studies of extensive grazing, covering 164 sites across different countries and climatic zones. Unlike previous published reviews we normalized the SOC and total nitrogen (TN) data to a 30 cm depth to be compatible with IPCC guidelines. We also calculated a normalized GI and divided the data into four main groups depending on the regional climate (dry warm, DW; dry cool, DC; moist warm, MW; moist cool, MC). Our results show that taken across all climatic zones and GIs, grazing (below the carrying capacity of the systems) results in a decrease in SOC storage, although its impact on SOC is climate-dependent. When assessed for different regional climates, all GI levels increased SOC stocks under the MW climate (+7.6%) whilst there were reductions under the MC climate (-19%). Under the DW and DC climates, only the low (+5.8%) and low to medium (+16.1%) grazing intensities, respectively, were associated with increased SOC stocks. High GI significantly increased SOC for C4-dominated grassland compared to C3-dominated grassland and C3-C4 mixed grasslands. It was also associated with significant increases in TN and bulk density but had no effect on soil pH. To protect grassland soils from degradation, we recommend that GI and management practices should be optimized according to climate region and grassland type (C3, C4 or C3-C4 mixed).

Managing broiler litter application rate and grazing to decrease watershed runoff losses.

PubMed

Sistani, K R; Brink, G E; Oldham, J L

2008-01-01

Pasture management and broiler litter application rate are critical factors influencing the magnitude of nutrients being transported by runoff from fields. We investigated the impact of pasture management and broiler litter application rate on nutrient runoff from bermudagrass (Cynodon dactylon) pastures. The experiment was conducted on a Ruston fine sandy loam with a factorial arrangement on 21 large paddocks. Runoff water was collected from natural rainfall events from 2001 to 2003. Runoff water and soil samples were analyzed for nutrients and sediments. Runoff was generally greater (29%) from grazed than hayed pastures regardless of the litter application rate. There was greater inorganic N in the runoff from grazed paddocks when litter rate was based on N rather than P. The mean total P loss per runoff event for all treatments ranged from 7 to 45 g ha(-1) and the grazed treatment with litter applied on N basis had the greatest total P loss. Total dissolved P was the dominant P fraction in the runoff, ranging from 85% to 93% of the total P. The soluble reactive P was greater for treatments with litter applied on N basis regardless of pasture management. Runoff total sediments were greater for N-based litter application compared to those which received litter on P basis. Our results indicate that litter may be applied on N basis if the pasture is hayed and the soil P is low. In contrast, litter rates should be based on a P-basis if pasture is grazed.

Cattle as ecosystem engineers: New grazing management enhances rangeland biodiversity

USDA-ARS?s Scientific Manuscript database

A confluence of factors has shaped the composition and structure of vegetation on rangelands in the American West. These factors include climate, soils, topography, history of grazing and fire (both wildfire and prescribed fire) as well as legacy effects from prior land management practices. Despite...

Simulating grazing practices in a complete livestock system model: estimating soil carbon storage and greenhouse gas emissions in grazed versus un-grazed agroecosystems using the Manure-DNDC model

NASA Astrophysics Data System (ADS)

Campbell, E. E.; Dorich, C.; Contosta, A.; Varner, R. K.

2017-12-01

In livestock agroecosystems, the combined contributions of enteric fermentation, manure management, and livestock grazing and/or feed production play an important role in agroecosystem carbon (C) storage and GHG losses, with complete livestock system models acting as important tools to evaluate the full impacts of these complex systems. The Manure-DeNitrification-DeComposition (DNDC) model is one such example, simulating impacts on C and nitrogen cycling, estimating methane, carbon dioxide, nitrous oxide, and ammonium dynamics in fields, manure storage, and enteric emissions. This allows the evaluation of differences in GHG and soil C impacts between conventional and organic dairy production systems, which differ in their use of grazed pasture versus confined feeding operations. However, Manure-DNDC has received limited testing in representing variations in grazed pasture management (i.e. intensive rotational grazing versus standard grazing practices). Using a set of forage biomass, soil C, and GHG emissions data collected at four sites across New England, we parameterized and validated Manure-DNDC estimations of GHG emissions and soil C in grazed versus un-grazed systems. Soil observations from these sites showed little effect from grazing practices, but larger soil carbon differences between farms. This may be due to spatial variation in SOC, making it difficult to measure and model, or due to controls of edaphic properties that make management moot. However, to further address these questions, model development will be needed to improve Manure-DNDC simulation of rotational grazing, as high stocking density grazing over short periods resulted in forage not re-growing sufficiently within the model. Furthermore, model simulations did not account for variation in interactions between livestock and soil given variability in field microclimates, perhaps requiring simulations that divide a single field into multiple paddocks to move towards more accurate evaluation of

Does pulse-grazing influence within- and between-grazing season dietary quality of yearling steers in shortgrass steppe?

USDA-ARS?s Scientific Manuscript database

Pulse-grazing, high stock density with short grazing periods (weeks) followed by long (months to > 1 year) rest periods, is a grazing management strategy posited to decrease preferential selection by cattle and increase utilization of forage, but influences on dietary quality of grazing animals in s...

Western land managers will need all available tools for adapting to climate change, including grazing: a critique of Beschta et al.

PubMed

Svejcar, Tony; Boyd, Chad; Davies, Kirk; Madsen, Matthew; Bates, Jon; Sheley, Roger; Marlow, Clayton; Bohnert, David; Borman, Mike; Mata-Gonzàlez, Ricardo; Buckhouse, John; Stringham, Tamzen; Perryman, Barry; Swanson, Sherman; Tate, Kenneth; George, Mel; Ruyle, George; Roundy, Bruce; Call, Chris; Jensen, Kevin; Launchbaugh, Karen; Gearhart, Amanda; Vermeire, Lance; Tanaka, John; Derner, Justin; Frasier, Gary; Havstad, Kris

2014-06-01

In a previous article, Beschta et al. (Environ Manag 51(2):474-491, 2013) argue that grazing by large ungulates (both native and domestic) should be eliminated or greatly reduced on western public lands to reduce potential climate change impacts. The authors did not present a balanced synthesis of the scientific literature, and their publication is more of an opinion article. Their conclusions do not reflect the complexities associated with herbivore grazing. Because grazing is a complex ecological process, synthesis of the scientific literature can be a challenge. Legacy effects of uncontrolled grazing during the homestead era further complicate analysis of current grazing impacts. Interactions of climate change and grazing will depend on the specific situation. For example, increasing atmospheric CO₂ and temperatures may increase accumulation of fine fuels (primarily grasses) and thus increase wildfire risk. Prescribed grazing by livestock is one of the few management tools available for reducing fine fuel accumulation. While there are certainly points on the landscape where herbivore impacts can be identified, there are also vast grazed areas where impacts are minimal. Broad scale reduction of domestic and wild herbivores to help native plant communities cope with climate change will be unnecessary because over the past 20-50 years land managers have actively sought to bring populations of native and domestic herbivores in balance with the potential of vegetation and soils. To cope with a changing climate, land managers will need access to all available vegetation management tools, including grazing.

Livestock grazing, wildlife habitat, and rangeland values

Treesearch

Paul R. Krausman; David E. Naugle; Michael R. Frisina; Rick Northrup; Vernon C. Bleich; William M. Block; Mark C. Wallace; Jeffrey D. Wright

2009-01-01

Livestock managers make and implement grazing management decisions to achieve a variety of objectives including livestock production, sustainable grazing, and wildlife habitat enhancement. Assessed values of grazing lands and ranches are often based on aesthetics and wildlife habitat or recreational values, which can exceed agricultural values, thus providing...

Can Managed Grazing be Part of Healthy Agroecosystems? Impacts of Various Systems on Soil Water and other Ecosystem Services

NASA Astrophysics Data System (ADS)

DeLonge, M. S.; Basche, A.; Gonzalez, J.

2016-12-01

Due to the vast extent of grazing lands, value of grassland ecosystems, and environmental impacts of the agricultural sector, it is becoming increasingly important to understand to what extent managed grazing can be part of healthy agroecosystems. For example, grazing systems can degrade soils, pollute water, and result in substantial direct and indirect animal emissions. On the other hand, well-managed grasslands can store more carbon, support more biodiversity, and require fewer inputs than croplands or other land uses. Systems analyses are needed to evaluate how much grazing management (e.g., altering stocking rate intensity or regime, integrating versus separating crops and livestock, adopting silvopasture techniques) can affect agroecosystem properties and farm viability. As a result of climate change and likely increases to rainfall variability, the effects of grazing systems on soil water properties are particularly important. The primary goal of this study is to use meta-analytic techniques to better understand how changes to grazing systems affect soil water properties, focusing on soil water infiltration rates. Another goal is to conduct a literature survey to assess how similar changes to grazing have influenced other ecosystem services (e.g., soil carbon, farm profitability) and to identify gaps in knowledge. To date, our meta-analysis includes over 100 paired comparisons (>30 studies) related to grazing. The analysis is a subset of a broader study of agroecological practices that to date includes >350 paired observations. Preliminary results point to significant variability, but suggest that integrating livestock into croplands decreases infiltration (12%), whereas other changings to grazing (decreasing stocking rates, moving from continuous to rotational grazing, or converting to a silvopasture system) can improve infiltration (by an average of 223% including all practices). Findings also suggest that removing livestock tends to increase infiltration

Effects of Grazing Management and Buffer Strips on Metal Runoff from Pastures Fertilized with Poultry Litter.

PubMed

Pilon, C; Moore, P A; Pote, D H; Martin, J W; DeLaune, P B

2017-03-01

Metal runoff from fields fertilized with poultry litter may pose a threat to aquatic systems. Buffer strips located adjacent to fields may reduce nutrients and solids in runoff. However, scant information exists on the long-term effects of buffer strips combined with grazing management on metal runoff from pastures. The objective of this study was to assess the 12-yr impact of grazing management and buffer strips on metal runoff from pastures receiving poultry litter. The research was conducted using 15 watersheds (25 m wide and 57 m long) with five treatments: hayed (H), continuously grazed (CG), rotationally grazed (R), rotationally grazed with a buffer strip (RB), and rotationally grazed with a fenced riparian buffer strip (RBR). Poultry litter was applied annually in spring at 5.6 Mg ha. Runoff samples were collected after every rainfall event. Aluminum (Al) and iron (Fe) concentrations were strongly and positively correlated with total suspended solids, indicating soil erosion was the primary source. Soluble Al and Fe were not related to total Al and Fe. However, there was a strong positive correlation between soluble and total copper (Cu) concentrations. The majority of total Cu and zinc was in water-soluble form. The CG treatment had the highest metal concentrations and loads of all treatments. The RBR and H treatments resulted in lower concentrations of total Al, Cu, Fe, potassium, manganese, and total organic carbon in the runoff. Rotational grazing with a fenced riparian buffer and converting pastures to hayfields appear to be effective management systems for decreasing concentrations and loads of metals in surface runoff from pastures fertilized with poultry litter. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Livestock grazing and wildlife: developing compatabilities.

Treesearch

Martin Vavra

2005-01-01

Livestock grazing has been considered detrimental to wildlife habitat. Managed gazing programs, however, have the potential to maintain habitat diversity and quality. In cases in which single-species management predominates (sage-grouse [Centrocercus urophasianus] or elk [Cervus elaphus nelsoni] winter range), grazing systems...

Effect of grazing on vegetation and soil of the heuweltjieveld in the Succulent Karoo, South Africa

NASA Astrophysics Data System (ADS)

Schmiedel, Ute; Röwer, Inga Ute; Luther-Mosebach, Jona; Dengler, Jürgen; Oldeland, Jens; Gröngröft, Alexander

2016-11-01

We asked how historical and recent grazing intensity affect the patchy landscape of the heuweltjieveld in the semi-arid biodiversity hotspot Succulent Karoo. The study was carried out on a communal farmland 80 km south-west of Springbok, in Namaqualand. Heuweltjies are roughly circular earth mounds that are regularly distributed in this landscape. We sampled plant species and life-form composition, diversity measures, habitat and soil variables in 100 m2 plots, placed in three visually distinguishable heuweltjie zones (centre, fringe, and matrix) and distributed across grazing camps with different recent and historic grazing intensities. Differences between heuweltjie zones were assessed with ANOVAs and multiple linear regressions. The effect of past and recent grazing intensity on soil and plant variables was analysed by Generalized Linear Models for each heuweltjie zone separately. The three zones constituted clearly distinguishable units in terms of vegetation and soil characteristics. Soil pH and cover of annual plants increased from matrix to centres, while total vegetation cover, species richness and perennial plant cover decreased in the same direction. Historic (pre-2000) grazing patterns had the strongest effects on fringes, showing the strongest soil and vegetation-related signs of overutilization with increased stocking density. Centres showed signs of overutilization irrespective of the stocking density. The much shorter exposure to recent grazing pattern (post-2000), which was nearly inverse to the historic grazing pattern, showed increase of vegetation cover (centres) and species richness (matrix) with recent grazing intensity. We interpret these effects as still visible responses of the lower grazing intensity in these camps during the historic period. No recovery under recent grazing was observed at any of the zones. We conclude that irrespective of their conducive growing conditions, once transformed to a disturbed state, heuweltjie centres recover

Using dual-purpose crops in sheep-grazing systems.

PubMed

Dove, Hugh; Kirkegaard, John

2014-05-01

The utilisation of dual-purpose crops, especially wheat and canola grown for forage and grain production in sheep-grazing systems, is reviewed. When sown early and grazed in winter before stem elongation, later-maturing wheat and canola crops can be grazed with little impact on grain yield. Recent research has sought to develop crop- and grazing-management strategies for dual-purpose crops. Aspects examined have been grazing effects on crop growth, recovery and yield development along with an understanding of the grazing value of the crop fodder, its implications for animal nutrition and grazing management to maximise live-weight gain. By alleviating the winter 'feed gap', the increase in winter stocking rate afforded by grazing crops allows crop and livestock production to be increased simultaneously on the same farm. Integration of dual-purpose wheat with canola on mixed farms provides further systems advantages related to widened operational windows, weed and disease control and risk management. Dual-purpose crops are an innovation that has potential to assist in addressing the global food-security challenge. © 2013 Society of Chemical Industry.

Explaining variability in first grazing season heifer growth combining individually measured parasitological and clinical indicators with exposure to gastrointestinal nematode infection based on grazing management practice.

PubMed

Merlin, Aurélie; Chauvin, Alain; Madouasse, Aurélien; Froger, Sébastien; Bareille, Nathalie; Chartier, Christophe

2016-07-30

The objective of our study was to explain the variability of average daily weight gain (ADWG) due to gastrointestinal nematode (GIN) infection for 291 non treated first grazing season (FGS) heifers, from 12 independent groups in the western part of France, by combining parasitological and clinical indicators at individual level and grazing management indicators at group level. Parasitological indicators were faecal egg count (FEC), anti Ostertagia ostertagi antibody level (Ostertagia ODR), and pepsinogen level. Clinical indicators were diarrhea score (DISCO) and breech soiling score (BSS). At group level, grazing management practice (GMP), based on three variables (supplementation, month of turnout, grazing season duration), was clustered into three categories reflecting low, medium or high exposure (EXP) to GIN. Depending on the groups, turnout was from mid-March to early July and housing was from mid-October to late November, with a FGS duration ranging from 4 to 8.4 months. At turnout, the mean age of heifers was 8 months (range: 6-16 months) and they weighed between 175 and 268kg. In each GMP category, FEC significantly decreased between the mid-season and the housing, while Ostertagia ODR and pepsinogen level increased gradually throughout the grazing season. In contrast, clinical indicators did not show any seasonal variation. In a multivariate linear model, 22% of the ADWG variability was significantly explained by two individual indicators (Ostertagia ODR: 12.6%, DISCO: 4.8%) and by the group indicator (GMP category: 4.8%). ADWG losses due to GIN exposure (Ostertagia ODR) were estimated up to 39kg per heifer for the overall grazing season. For groups within the low EXP category the difference between animals with low (<697g/day) or high (>697g/day) ADWG was explained by the clinical indicator DISCO. In contrast, for groups within the medium and high EXP categories this difference was explained by a parasitological indicator (Ostertagia ODR). This study

Grazing in central hardwood forests

Treesearch

Robert A. McQuilkin; Harold Scholten

1989-01-01

Woodland grazing is a major forestry and land management problem in parts of the central hardwood region. Most forest grazing is by cattle and, to a lesser extent, hogs in woodlands adjacent to pastures or feedlots. The practice is particularly common in the cattle producing areas of the Corn Belt where often 50 percent or more of the upland forest is grazed. Woodland...

Effects of stocking rate, forage management, and grazing management on performance and economics of cow-calf production in Southwest Arkansas.

PubMed

Beck, P A; Stewart, C B; Sims, M B; Gadberry, M S; Jennings, J A

2016-09-01

The objective this research was to determine the effect of application of multiple grazing management practices at 2 stocking rates (SR) on the productivity and economics of the cow-calf enterprise in the Southeastern United States over a 4-yr period. Pasture management systems included: continuous grazing management at a moderate SR (0.8 ha/cow; CG) without additional forage management, rotational grazing management at a moderate SR (0.8 ha/cow (MR) with addition of stockpiled bermudagrass [ (L.) Pers.] and complementary cool season annuals, and rotational grazing management similar to MR but with a high SR (0.4 ha/cow; HR). Stockpiling in MR and HR was managed by fertilization of 0.2 ha/cow of bermudagrass in early August with 168 kg ammonium nitrate and deferring grazing until November. Wheat (; 112 kg/ha) and annual ryegrass ( Lam.; 28 kg/ha) were interseeded (0.2 ha/cow) in HR and MR with a no-till drill in the fall. Cow and calf performance and economics data were analyzed by ANOVA using the MIXED procedure of SAS (SAS Inst. Inc., Cary, NC) and pregnancy percentage was analyzed using the GLIMMIX procedure of SAS; pasture was the experimental unit and year was the random block. Hay feeding days decreased ( < 0.01) from 107 ± 10.9 d for CG to 37 ± 10.9 d for HR, which was further reduced ( = 0.01) to 15 ± 10.9 d for MR. Pregnancy percentage did not differ ( = 0.20) among treatments. Weaning BW in CG (237 ± 7.3 kg) tended ( = 0.09) to be greater than in MR (227 ± 7.3 kg) and were greater ( < 0.01) than in HR (219 ± 7.3 kg). However, total weaning BW per hectare was 89% greater ( < 0.01) for HR compared with CG and MR, which did not differ ( = 0.31). With rotational stocking, there was the opportunity to harvest excess forage as hay in both MR and HR with a net value of US$52.90/ha ± 25.73 and $15.50/ha ± 25.73, respectively. Net returns per hectare did not differ ( = 0.30) between CG ($429 ± 63.0/ha) and MR ($479 ± 63.0/ha) but were increased ( < 0

50 CFR 35.9 - Livestock grazing.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Livestock grazing. 35.9 Section 35.9... NATIONAL WILDLIFE REFUGE SYSTEM WILDERNESS PRESERVATION AND MANAGEMENT General Rules § 35.9 Livestock grazing. (a) The grazing of livestock, where established prior to the date of legislation which designates...

Arbuscular mycorrhizal fungi associated with vegetation and soil parameters under rest grazing management in a desert steppe ecosystem.

PubMed

Bai, Gegenbaoleer; Bao, Yuying; Du, Guoxin; Qi, Yunlong

2013-05-01

The impact of rest grazing on arbuscular mycorrhizal fungi (AMF) and the interactions of AMF with vegetation and soil parameters under rest grazing condition were investigated between spring and late summer in a desert steppe ecosystem with different grazing managements (rest grazing with different lengths of resting period, banned or continuous grazing) in Inner Mongolia, China. AMF diversity and colonization, vegetation biomass, soil properties and soil phosphatase activity were examined. In rest grazing areas of 60 days, AMF spore number and diversity index at a 0-10 cm soil depth as well as vesicular and hyphal colonization rates were higher compared with other grazing treatments. In addition, soil organic matter and total N contents were highest and soil alkaline phosphatase was most active under 60-day rest grazing. In August and September, these areas also had the highest amount of aboveground vegetation. The results indicated that resting grazing for an appropriate period of time in spring has a positive effect on AMF sporulation, colonization and diversity, and that under rest grazing conditions, AMF parameters are positively correlated with some soil characteristics.

Carbon sequestration potential of grazed pasture depends on prior management history

USDA-ARS?s Scientific Manuscript database

Grazed pastures are often assumed to be net sinks for removing carbon dioxide from the atmosphere and thus, are promoted as a management practice that can help mitigate climate change. The ability to serve as a C sink is especially pronounced following a history of tillage and row crop production. I...

Variability in carbon dioxide fluxes among six winter wheat paddocks managed under different tillage and grazing practices

USDA-ARS?s Scientific Manuscript database

Carbon dioxide (CO2) fluxes from six winter wheat (Triticum aestivum L.) paddocks (grain only, graze-grain, and graze-out) managed under conventional till (CT) and no-till (NT) systems were synthesized for the 2016-2017 growing season to compare the magnitudes and seasonal dynamics of CO2 fluxes and...

36 CFR 222.4 - Changes in grazing permits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... RANGE MANAGEMENT Grazing and Livestock Use on the National Forest System § 222.4 Changes in grazing... use permits in whole or in part as follows: (1) Cancel permits where lands grazed under the permit are... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Changes in grazing permits...

Mob grazing for dairy cows

USDA-ARS?s Scientific Manuscript database

Proponents of mob grazing emphasize increased forage use efficiency and soil improvement by grazing mature forage with stocking densities up to 560,425 lb/ac of beef cattle on small paddocks with rest periods up to 125 days. However, it is unclear if this management technique is appropriate for dair...

Alfalfa weevil (Coleoptera:Curculionidae) management in alfalfa by spring grazing with cattle.

PubMed

Buntin, G D; Bouton, J H

1996-12-01

The effect of continuous, intensive grazing by cattle in the 1st alfalfa growth cycle on larval densities of the alfalfa weevil, Hyera postica (Gyllenhal), was evaluated in "Alfagraze' and "Apollo' alfalfa, which are tolerant and not tolerant to grazing, respectively. In small-cage exclusion trials, grazing reduced larval numbers in 1991 by 65% in Alfagraze and by 32% in Apollo. Larval numbers in 1992 were low (< or = 0.6 larvae per stem) and were not reduced significantly by grazing. Grazing and use of early insecticide treatments of permethrin or carbofuran at low rates with < or = 7-d grazing restrictions to suppress larval numbers before grazing also were examined in large-plot exclusion trails in 1993 and 1994. Grazing reduced larval densities by 60% in 1993 and 45% in 1994 during a 3-wk period beginning 3 wk after grazing was initiated. However, alfalfa weevil larvae caused moderate leaf injury in 1993 and severe injury in 1994 before grazing reduced larval numbers. Use of permethrin at 0.11 kg (AI)/ha or carbofuran or chlorpyrifos at 0.28 kg (AI)/ha effectively reduced larval numbers and prevented leaf injury before grazing began. Therefore, a combination of an early application of an insecticide treatment with a short grazing restriction followed by continuous grazing will control alfalfa weevil larvae while allowing cattle to graze and directly use forage of grazing-tolerant alfalfa.

Response of mountain meadows to grazing by recreational pack stock

USGS Publications Warehouse

Cole, David N.; Van Wagtendonk, Jan W.; McClaran, Mitchel P.; Moore, Peggy E.; McDougald, Neil K.

2004-01-01

Effects of recreational pack stock grazing on mountain meadows in Yosemite National Park were assessed in a 5-year study. Yosemite is a designated wilderness, to be managed such that its natural conditions are preserved. Studies were conducted in 3 characteristic meadow types: shorthair sedge (Carex filifolia Nutt.), Brewer's reed grass (Calamagrostis breweri Thurber), and tufted hairgrass [Deschampsia cespitosa (L.) Beauv.]. Horses and mules grazed experimental plots at intensities of 15 to 69% utilization for 4 seasons. In all 3 meadows, grazing caused decreases in productivity. The mean reduction after 4 years of grazing was 18% in the shorthair sedge meadow, 17% in the Brewer's reed grass meadow, and 22% in the tufted hairgrass meadow. Grazing also caused shifts in basal groundcover (usually a reduction in vegetation cover and increase in bare soil cover), and changes in species composition. Productivity and vegetation cover decreased as percent utilization increased, while bare soil cover increased as utilization increased. Changes in species composition were less predictably related to differences in grazing intensity. Passive management of grazing is insufficient in wilderness areas that are regularly used by groups with recreational stock. Wilderness managers need to monitor meadow conditions and the grazing intensities that occur. Our study suggests that biomass and ground cover are more sensitive indicators of grazing impact than species composition. Managers must make decisions about maximum acceptable levels of grazing impact and then develop guidelines for maximum use levels, based on data such as ours that relates grazing intensity to meadow response.

Landscape management of fire and grazing regimes alters the fine-scale habitat utilisation by feral cats.

PubMed

McGregor, Hugh W; Legge, Sarah; Jones, Menna E; Johnson, Christopher N

2014-01-01

Intensification of fires and grazing by large herbivores has caused population declines in small vertebrates in many ecosystems worldwide. Impacts are rarely direct, and usually appear driven via indirect pathways, such as changes to predator-prey dynamics. Fire events and grazing may improve habitat and/or hunting success for the predators of small mammals, however, such impacts have not been documented. To test for such an interaction, we investigated fine-scale habitat selection by feral cats in relation to fire, grazing and small-mammal abundance. Our study was conducted in north-western Australia, where small mammal populations are sensitive to changes in fire and grazing management. We deployed GPS collars on 32 cats in landscapes with contrasting fire and grazing treatments. Fine-scale habitat selection was determined using discrete choice modelling of cat movements. We found that cats selected areas with open grass cover, including heavily-grazed areas. They strongly selected for areas recently burnt by intense fires, but only in habitats that typically support high abundance of small mammals. Intense fires and grazing by introduced herbivores created conditions that are favoured by cats, probably because their hunting success is improved. This mechanism could explain why, in northern Australia, impacts of feral cats on small mammals might have increased. Our results suggest the impact of feral cats could be reduced in most ecosystems by maximising grass cover, minimising the incidence of intense fires, and reducing grazing by large herbivores.

Landscape Management of Fire and Grazing Regimes Alters the Fine-Scale Habitat Utilisation by Feral Cats

PubMed Central

McGregor, Hugh W.; Legge, Sarah; Jones, Menna E.; Johnson, Christopher N.

2014-01-01

Intensification of fires and grazing by large herbivores has caused population declines in small vertebrates in many ecosystems worldwide. Impacts are rarely direct, and usually appear driven via indirect pathways, such as changes to predator-prey dynamics. Fire events and grazing may improve habitat and/or hunting success for the predators of small mammals, however, such impacts have not been documented. To test for such an interaction, we investigated fine-scale habitat selection by feral cats in relation to fire, grazing and small-mammal abundance. Our study was conducted in north-western Australia, where small mammal populations are sensitive to changes in fire and grazing management. We deployed GPS collars on 32 cats in landscapes with contrasting fire and grazing treatments. Fine-scale habitat selection was determined using discrete choice modelling of cat movements. We found that cats selected areas with open grass cover, including heavily-grazed areas. They strongly selected for areas recently burnt by intense fires, but only in habitats that typically support high abundance of small mammals. Intense fires and grazing by introduced herbivores created conditions that are favoured by cats, probably because their hunting success is improved. This mechanism could explain why, in northern Australia, impacts of feral cats on small mammals might have increased. Our results suggest the impact of feral cats could be reduced in most ecosystems by maximising grass cover, minimising the incidence of intense fires, and reducing grazing by large herbivores. PMID:25329902

Improved grazing management may increase soil carbon sequestration in temperate steppe

NASA Astrophysics Data System (ADS)

Chen, Wenqing; Huang, Ding; Liu, Nan; Zhang, Yingjun; Badgery, Warwick B.; Wang, Xiaoya; Shen, Yue

2015-07-01

Different grazing strategies impact grassland plant production and may also regulate the soil carbon formation. For a site in semiarid temperate steppe, we studied the effect of combinations of rest, high and moderate grazing pressure over three stages of the growing season, on the process involved in soil carbon sequestration. Results show that constant moderate grazing (MMM) exhibited the highest root production and turnover accumulating the most soil carbon. While deferred grazing (RHM and RMH) sequestered less soil carbon compared to MMM, they showed higher standing root mass, maintained a more desirable pasture composition, and had better ability to retain soil N. Constant high grazing pressure (HHH) caused diminished above- and belowground plant production, more soil N losses and an unfavorable microbial environment and had reduced carbon input. Reducing grazing pressure in the last grazing stage (HHM) still had a negative impact on soil carbon. Regression analyses show that adjusting stocking rate to ~5SE/ha with ~40% vegetation utilization rate can get the most carbon accrual. Overall, the soil carbon sequestration in the temperate grassland is affected by the grazing regime that is applied, and grazing can be altered to improve soil carbon sequestration in the temperate steppe.

Improved grazing management may increase soil carbon sequestration in temperate steppe.

PubMed

Chen, Wenqing; Huang, Ding; Liu, Nan; Zhang, Yingjun; Badgery, Warwick B; Wang, Xiaoya; Shen, Yue

2015-07-03

Different grazing strategies impact grassland plant production and may also regulate the soil carbon formation. For a site in semiarid temperate steppe, we studied the effect of combinations of rest, high and moderate grazing pressure over three stages of the growing season, on the process involved in soil carbon sequestration. Results show that constant moderate grazing (MMM) exhibited the highest root production and turnover accumulating the most soil carbon. While deferred grazing (RHM and RMH) sequestered less soil carbon compared to MMM, they showed higher standing root mass, maintained a more desirable pasture composition, and had better ability to retain soil N. Constant high grazing pressure (HHH) caused diminished above- and belowground plant production, more soil N losses and an unfavorable microbial environment and had reduced carbon input. Reducing grazing pressure in the last grazing stage (HHM) still had a negative impact on soil carbon. Regression analyses show that adjusting stocking rate to ~5SE/ha with ~40% vegetation utilization rate can get the most carbon accrual. Overall, the soil carbon sequestration in the temperate grassland is affected by the grazing regime that is applied, and grazing can be altered to improve soil carbon sequestration in the temperate steppe.

Cyanobacterial crusts linked to soil productivity under different grazing management practices in Northern Australia

NASA Astrophysics Data System (ADS)

Alchin, Bruce; Williams, Wendy

2015-04-01

In arid and semi-arid Australia, the central role of healthy soil ecosystems in broad-acre grazing lands may be attributed to the widespread presence of cyanobacterial crusts. In terms of soil nutrient cycling and stability their role is particularly crucial in a climate dominated by annual dry seasons and variable wet seasons. In this study, we aimed to measure the contribution of cyanobacteria to soil nutrient cycling under contrasting levels of disturbance associated with grazing management. Field sampling was carried out on six paired sites (twelve properties) located across an east-west 3,000 km transect that covered different rangeland types on grazing properties in northern Australia (Queensland, Northern Territory and Western Australia). At each location paired sites were established and two different management systems were assessed, cell-paddock rotations (25-400 ha) and continuous grazing (200-2,000 ha). Cyanobacterial soil crusts were recorded from all of the twelve sites and cyanobacteria with the capacity to fix nitrogen were found at ten of the twelve sites. The overall diversity of cyanobacteria varied from three to ten species under any type of grazing system. As field work was conducted in the dry season, it is likely that the diversity may be greater in the wet season than the initial data may indicate. The average cyanobacterial soil crust cover across soil surfaces, between grass tussocks, during the dry season was estimated to be 50.9% and, 42.6% in the early wet season. This reflected longer established crust cover (dry season) versus newly established crusts. There was a high level of variability in the biomass of cyanobacteria however; the grazing system did not have any marked effect on the biomass for any one rangeland type. The grazing system differences did not appear to significantly influence the diversity at any location except on a floodplain in the Pilbara (WA). Biological nitrogen fixation by cyanobacteria was recorded at all

25 CFR 166.307 - Will the grazing capacity be increased if I graze adjacent trust or non-trust rangelands not...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Will the grazing capacity be increased if I graze adjacent trust or non-trust rangelands not covered by the permit? 166.307 Section 166.307 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING PERMITS Land and Operations Management...

How Does “Hunger” Level Impact Grazing Behavior?

USDA-ARS?s Scientific Manuscript database

Grazing behavior can be influenced through feeding and grazing management decisions. Research at our USDA-ARS lab showed that ruminal fill, or how ‘hungry’ the cow is, can affect grazing behavior. Cows that had less ruminal fill took a bigger bite that was shallow and wide, compared to a ‘full’ cow ...

Patch-burn grazing management, vegetation heterogeneity and avian responses in a semi-arid grassland

USDA-ARS?s Scientific Manuscript database

Anthropogenic changes to disturbance regimes in grasslands, and associated homogenization of vegetation structure, have been implicated as factors contributing to declines in populations of grassland birds in North America. We examined the influence of patch-burn grazing management, which employs sp...

An agent-based model of cattle grazing toxic Geyer's larkspur.

PubMed

Jablonski, Kevin E; Boone, Randall B; Meiman, Paul J

2018-01-01

By killing cattle and otherwise complicating management, the many species of larkspur (Delphinium spp.) present a serious, intractable, and complex challenge to livestock grazing management in the western United States. Among the many obstacles to improving our understanding of cattle-larkspur dynamics has been the difficulty of testing different grazing management strategies in the field, as the risk of dead animals is too great. Agent-based models (ABMs) provide an effective method of testing alternate management strategies without risk to livestock. ABMs are especially useful for modeling complex systems such as livestock grazing management, and allow for realistic bottom-up encoding of cattle behavior. Here, we introduce a spatially-explicit, behavior-based ABM of cattle grazing in a pasture with a dangerous amount of Geyer's larkspur (D. geyeri). This model tests the role of herd cohesion and stocking density in larkspur intake, finds that both are key drivers of larkspur-induced toxicosis, and indicates that alteration of these factors within realistic bounds can mitigate risk. Crucially, the model points to herd cohesion, which has received little attention in the discipline, as playing an important role in lethal acute toxicosis. As the first ABM to model grazing behavior at realistic scales, this study also demonstrates the tremendous potential of ABMs to illuminate grazing management dynamics, including fundamental aspects of livestock behavior amidst ecological heterogeneity.

Coastal zone management

NASA Technical Reports Server (NTRS)

Tilton, E. L., III

1975-01-01

A panel of federal and state representatives concerned with coastal zone affairs discussed their problems in this area. In addition, several demonstrations of the application of remote sensing technology to coastal zone management were described. These demonstrations were performed by several agencies in a variety of geographical areas.

Mixed Grazing Systems Benefit both Upland Biodiversity and Livestock Production

PubMed Central

Fraser, Mariecia D.; Moorby, Jon M.; Vale, James E.; Evans, Darren M.

2014-01-01

Background With world food demand expected to double by 2050, identifying farming systems that benefit both agricultural production and biodiversity is a fundamentally important challenge for the 21st century, but this has to be achieved in a sustainable way. Livestock grazing management directly influences both economic outputs and biodiversity on upland farms while contributing to potentially damaging greenhouse gas emissions, yet no study has attempted to address these impacts simultaneously. Methods Using a replicated, landscape-scale field experiment consisting of five management ‘systems’ we tested the effects of progressively altering elements within an upland farming system, viz i) incorporating cattle grazing into an upland sheep system, ii) integrating grazing of semi-natural rough grazing into a mixed grazing system based on improved pasture, iii) altering the stocking ratio within a mixed grazing system, and iv) replacing modern crossbred cattle with a traditional breed. We quantified the impacts on livestock productivity and numbers of birds and butterflies over four years. Results, Conclusion and Significance We found that management systems incorporating mixed grazing with cattle improve livestock productivity and reduce methane emissions relative to sheep only systems. Systems that also included semi-natural rough grazing consistently supported more species of birds and butterflies, and it was possible to incorporate bouts of summer grazing of these pastures by cattle to meet habitat management prescriptions without compromising cattle performance overall. We found no evidence that the system incorporating a cattle breed popular as a conservation grazer was any better for bird and butterfly species richness than those based on a mainstream breed, yet methane emissions from such a system were predicted to be higher. We have demonstrated that mixed upland grazing systems not only improve livestock production, but also benefit biodiversity

Mixed grazing systems benefit both upland biodiversity and livestock production.

PubMed

Fraser, Mariecia D; Moorby, Jon M; Vale, James E; Evans, Darren M

2014-01-01

With world food demand expected to double by 2050, identifying farming systems that benefit both agricultural production and biodiversity is a fundamentally important challenge for the 21(st) century, but this has to be achieved in a sustainable way. Livestock grazing management directly influences both economic outputs and biodiversity on upland farms while contributing to potentially damaging greenhouse gas emissions, yet no study has attempted to address these impacts simultaneously. Using a replicated, landscape-scale field experiment consisting of five management 'systems' we tested the effects of progressively altering elements within an upland farming system, viz i) incorporating cattle grazing into an upland sheep system, ii) integrating grazing of semi-natural rough grazing into a mixed grazing system based on improved pasture, iii) altering the stocking ratio within a mixed grazing system, and iv) replacing modern crossbred cattle with a traditional breed. We quantified the impacts on livestock productivity and numbers of birds and butterflies over four years. We found that management systems incorporating mixed grazing with cattle improve livestock productivity and reduce methane emissions relative to sheep only systems. Systems that also included semi-natural rough grazing consistently supported more species of birds and butterflies, and it was possible to incorporate bouts of summer grazing of these pastures by cattle to meet habitat management prescriptions without compromising cattle performance overall. We found no evidence that the system incorporating a cattle breed popular as a conservation grazer was any better for bird and butterfly species richness than those based on a mainstream breed, yet methane emissions from such a system were predicted to be higher. We have demonstrated that mixed upland grazing systems not only improve livestock production, but also benefit biodiversity, suggesting a 'win-win' solution for farmers and conservationists.

Effects of Grazing Management in Brachiaria grass-forage Peanut Pastures on Canopy Structure and Forage Intake.

PubMed

Gomes, F K; Oliveira, M D B L; Homem, B G C; Boddey, R M; Bernardes, T F; Gionbelli, M P; Lara, M A S; Casagrande, D R

2018-06-13

Maintenance of mixed grass-legume pastures for stand longevity and improved animal utilization is a challenge in warm-season climates. The goal of this study was to assess grazing management on stand persistence, forage intake, and N balance of beef heifers grazing mixed pastures of Brachiaria brizantha and Arachis pintoi. A two-year experiment was carried out in Brazil, where four grazing management were assessed: rest period interrupted at 90%, 95%, and 100% of light interception (LI) and a fixed rest period of 42 days (90LI, 95LI, 100LI, and 42D, respectively). The LI were taken at 50 points at ground level and at five points above the canopy for each paddock using a canopy analyzer. For all treatments, the post-grazing stubble height was 15 cm. Botanical composition and canopy structure characteristics such as canopy height, forage mass, and vertical distribution of the morphological composition were evaluated pre-and post-grazing. Forage chemical composition, intake, and microbial synthesis were also determined. A randomized complete block design was used, considering the season of the year as a repeated measure over time. Grazing management and season were considered fixed, while block and year were considered random effects. In the summer, legume mass accounted for 19% of the canopy at 100LI, which was less than other treatments (a mean of 30%). The 100LI treatment had a greater grass stem mass compared with other treatments. In terms of vertical distribution for 100LI, 38.6% of the stem mass was above the stubble height, greater than the 5.7% for other treatments. The canopy structure limited neutral detergent fiber intake (P = 0.007) at 100LI (1.02% of BW/d), whereas 42D, 90LI, and 95LI treatments had NDF intake close to 1.2% of BW/d. The intake of digestible organic matter (OM; P = 0.007) and the ratio of crude protein/digestible OM (P < 0.001) were less at 100LI in relation to the other treatments. The production of microbial N (P < 0.001) and efficiency

Progress Report: Stratton Ecological Research Site - An Experimental Approach to Assess Effects of Various Grazing Treatments on Vegetation and Wildlife Communities Across Managed Burns and Habitat Controls

USGS Publications Warehouse

Erickson, Heidi J.; Aldridge, Cameron L.; Hobbs, N. Thompson

2009-01-01

Understanding how management practices affect wildlife is fundamental to wise decisions for conservation of public lands. Prescribed fire and grazing timing are two management tools frequently used within publicly owned sagebrush ecosystems. We conducted a variety of surveys in order to assess the impacts of grazing timing strategies (early summer before peak green-up, mid-summer at peak green-up, and late summer after peak green-up) in conjunction with prescribed fire on avian and small mammal populations in a high-elevation sagebrush ecosystem. Avian surveys resulted in a large detection sample size for three bird species: Brewer's sparrow (Spizella breweri), horned lark (Eremophila alpestris), and vesper sparrow (Pooecetes gramineus). Brewer's sparrows had the lowest number of detections within the mid-summer grazing treatment compared to early and late summer grazing treatments, while horned larks and vesper sparrows had higher detection frequencies within the late summer grazing treatment. Summer and fall sage-grouse (Centrocercus urophasianus) pellet counts revealed that the greatest over-winter and over-summer use by sage-grouse occurred within the early summer grazing treatment with minimal use of burn treatment areas across all grazing treatments. Deer-mice (Peromyscus maniculatus) represented approximately 90 percent of small mammals captured and were most prevalent within the mid-summer grazing treatment. Sagebrush cover was greatest within the mid-summer grazing treatment. We monitored 50 and 103 nests in 2007 and 2008, respectively. The apparent success rate for shrub-obligate nesting species was 58 percent in 2007 and 63 percent in 2008. This research will support management of sagebrush ecosystems by providing public land managers with direct comparisons of wildlife response to management regimes.

Livestock grazing and the desert tortoise in the Mojave Desert

USGS Publications Warehouse

Oldemeyer, John L.

1994-01-01

A large part of the Mojave Desert is not in pristine condition, and some current conditions can be related to past grazing-management practices. No information could be found on densities of the desert tortoise (Gopherus agassizii) or on vegetative conditions of areas that had not been grazed to allow managers a comparison of range conditions with data on tortoises. Experimental information to assess the effect of livestock grazing on tortoises is lacking, and researchers have not yet examined whether the forage that remains after grazing is sufficient to meet the nutritional needs of desert tortoises.

Estimating influence of stocking regimes on livestock grazing distributions

Treesearch

Matthew J. Rinella; Marty Vavra; Bridgett J. Naylor; Jennifer M. Boyd

2011-01-01

Livestock often concentrate grazing in particular regions of landscapes while partly or wholly avoiding other regions. Dispersing livestock from the heavily grazed regions is a central challenge in grazing land management. Position data gathered from GPS-collared livestock hold potential for increasing knowledge of factors driving livestock aggregation patterns, but...

25 CFR 166.305 - When is grazing capacity determined?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false When is grazing capacity determined? 166.305 Section 166.305 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING PERMITS Land and Operations Management § 166.305 When is grazing capacity determined? Before we grant, modify, or...

Grazing management effects on sediment, phosphorus, and pathogen loading of streams in cool-season grass pastures.

PubMed

Schwarte, Kirk A; Russell, James R; Kovar, John L; Morrical, Daniel G; Ensley, Steven M; Yoon, Kyoung-Jin; Cornick, Nancy A; Cho, Yong Il

2011-01-01

Erosion and runoff from pastures may lead to degradation of surface water. A 2-yr grazing study was conducted to quantify the effects of grazing management on sediment, phosphorus (P), and pathogen loading of streams in cool-season grass pastures. Six adjoining 12.1-ha pastures bisected by a stream in central Iowa were divided into three treatments: continuous stocking with unrestricted stream access (CSU), continuous stocking with restricted stream access (CSR), and rotational stocking (RS). Rainfall simulations on stream banks resulted in greater ( < 0.10) proportions of applied precipitation and amounts of sediment and P transported in runoff from bare sites than from vegetated sites across grazing treatments. Similar differences were observed comparing vegetated sites in CSU and RS pastures with vegetated sites in CSR pastures. Bovine enterovirus was shed by an average of 24.3% of cows during the study period and was collected in the runoff of 8.3 and 16.7% of runoff simulations on bare sites in CSU pastures in June and October of 2008, respectively, and from 8.3% of runoff simulations on vegetated sites in CSU pastures in April 2009. Fecal pathogens (bovine coronavirus [BCV], bovine rotavirus group A, and O157:H7) shed or detected in runoff were almost nonexistent; only BCV was detected in feces of one cow in August of 2008. Erosion of cut-banks was the greatest contributor of sediment and P loading to the stream; contributions from surface runoff and grazing animals were considerably less and were minimized by grazing management practices that reduced congregation of cattle by pasture streams. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Home on the range: might the cattle peacefully graze?

Treesearch

Sally Duncan

1999-01-01

Grazing and how it impacts the landscape is a concern for public and private land managers. This issue of "Science Findings" examines the issue of cattle and grazing and provides some background, perspective, and research results on various grazing systems. Researchers Jim McIver, of the Forest Service's Blue Mountains Natural Resources Institute, and...

The economic cost of noxious weeds on Montana grazing lands

USDA-ARS?s Scientific Manuscript database

We distributed a 16-question survey concerning noxious weed abundances, impacts and management to livestock producers grazing on privately-owned or leased grazing lands in Montana. The noxious weeds most commonly reported as being present on respondents’ grazing units were Canada thistle (64% of gra...

Grazing management contributions to net global warming potential: a long-term evaluation in the Northern Great Plains.

PubMed

Liebig, M A; Gross, J R; Kronberg, S L; Phillips, R L; Hanson, J D

2010-01-01

The role of grassland ecosystems as net sinks or sources of greenhouse gases (GHGs) is limited by a paucity of information regarding management impacts on the flux of nitrous oxide (N(2)O) and methane (CH(4)). Furthermore, no long-term evaluation of net global warming potential (GWP) for grassland ecosystems in the northern Great Plains (NGP) of North America has been reported. Given this need, we sought to determine net GWP for three grazing management systems located within the NGP. Grazing management systems included two native vegetation pastures (moderately grazed pasture [MGP], heavily grazed pasture [HGP]) and a heavily grazed crested wheatgrass [Agropyron desertorum (Fisch. ex. Link) Schult.] pasture (CWP) near Mandan, ND. Factors evaluated for their contribution to GWP included (i) CO(2) emissions associated with N fertilizer production and application, (ii) literature-derived estimates of CH(4) production for enteric fermentation, (iii) change in soil organic carbon (SOC) over 44 yr using archived soil samples, and (iv) soil-atmosphere N(2)O and CH(4) fluxes over 3 yr using static chamber methodology. Analysis of SOC indicated all pastures to be significant sinks for SOC, with sequestration rates ranging from 0.39 to 0.46 Mg C ha(-1) yr(-1). All pastures were minor sinks for CH(4) (<2.0 kg CH(4)-C ha(-1) yr(-1)). Greater N inputs within CWP contributed to annual N(2)O emission nearly threefold greater than HGP and MGP. Due to differences in stocking rate, CH(4) production from enteric fermentation was nearly threefold less in MGP than CWP and HGP. When factors contributing to net GWP were summed, HGP and MGP were found to serve as net CO(2equiv.) sinks, while CWP was a net CO(2equiv.) source. Values for GWP and GHG intensity, however, indicated net reductions in GHG emissions can be most effectively achieved through moderate stocking rates on native vegetation in the NGP.

From the lab bench: A systematic approach to grazing cattle

USDA-ARS?s Scientific Manuscript database

A column was written to discuss the use of grazing systems to overcome challenges of managing grazed pastures. Kentucky cattlemen must manage around summer slumps in growth of cool-season perennial grasses, periodic drought, and cattle markets that do not always cooperate with pasture growth patter...

The multi-year cumulative effects of alternative stocking rate and grazing management practices on pasture productivity and utilization efficiency.

PubMed

McCarthy, B; Delaby, L; Pierce, K M; McCarthy, J; Fleming, C; Brennan, A; Horan, B

2016-05-01

) utilization per hectare increased significantly with increasing SR (+0.026 and +0.081 for MSR and HSR, respectively). These results quantify the significant effect of grazing management practices on the feed production capability of modern perennial ryegrass pastures for intensive grazing dairy production systems. Furthermore, these results highlight the importance of consistently imposing grazing treatments over multiple years, and within integrated whole farm systems, to accurately assess the longer term effects of alternate grazing management practices on pasture productivity. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Modeling the grazing effect on dry grassland carbon cycling with modified Biome-BGC grazing model

NASA Astrophysics Data System (ADS)

Luo, Geping; Han, Qifei; Li, Chaofan; Yang, Liao

2014-05-01

Identifying the factors that determine the carbon source/sink strength of ecosystems is important for reducing uncertainty in the global carbon cycle. Arid grassland ecosystems are a widely distributed biome type in Xinjiang, Northwest China, covering approximately one-fourth the country's land surface. These grasslands are the habitat for many endemic and rare plant and animal species and are also used as pastoral land for livestock. Using the modified Biome-BGC grazing model, we modeled carbon dynamics in Xinjiang for grasslands that varied in grazing intensity. In general, this regional simulation estimated that the grassland ecosystems in Xinjiang acted as a net carbon source, with a value of 0.38 Pg C over the period 1979-2007. There were significant effects of grazing on carbon dynamics. An over-compensatory effect in net primary productivity (NPP) and vegetation carbon (C) stock was observed when grazing intensity was lower than 0.40 head/ha. Grazing resulted in a net carbon source of 23.45 g C m-2 yr-1, which equaled 0.37 Pg in Xinjiang in the last 29 years. In general, grazing decreased vegetation C stock, while an increasing trend was observed with low grazing intensity. The soil C increased significantly (17%) with long-term grazing, while the soil C stock exhibited a steady trend without grazing. These findings have implications for grassland ecosystem management as it relates to carbon sequestration and climate change mitigation, e.g., removal of grazing should be considered in strategies that aim to increase terrestrial carbon sequestrations at local and regional scales. One of the greatest limitations in quantifying the effects of herbivores on carbon cycling is identifying the grazing systems and intensities within a given region. We hope our study emphasizes the need for large-scale assessments of how grazing impacts carbon cycling. Most terrestrial ecosystems in Xinjiang have been affected by disturbances to a greater or lesser extent in the past

Satellite-Derived Management Zones

NASA Technical Reports Server (NTRS)

Lepoutre, Damien; Layrol, Laurent

2005-01-01

The term "satellite-derived management zones" (SAMZ) denotes agricultural management zones that are subdivisions of large fields and that are derived from images of the fields acquired by instruments aboard Earth-orbiting satellites during approximately the past 15 years. "SAMZ" also denotes the methodology and the software that implements the methodology for creating such zones. The SAMZ approach is one of several products of continuing efforts to realize a concept of precision agriculture, which involves optimal variations in seeding, in application of chemicals, and in irrigation, plus decisions to farm or not to farm certain portions of fields, all in an effort to maximize profitability in view of spatial and temporal variations in the growth and health of crops, and in the chemical and physical conditions of soils. As used here, "management zone" signifies, more precisely, a subdivision of a field within which the crop-production behavior is regarded as homogeneous. From the perspective of precision agriculture, management zones are the smallest subdivisions between which the seeding, application of chemicals, and other management parameters are to be varied. In the SAMZ approach, the main sources of data are the archives of satellite imagery that have been collected over the years for diverse purposes. One of the main advantages afforded by the SAMZ approach is that the data in these archives can be reused for purposes of precision agriculture at low cost. De facto, these archives contain information on all sources of variability within a field, including weather, crop types, crop management, soil types, and water drainage patterns. The SAMZ methodology involves the establishment of a Web-based interface based on an algorithm that generates management zones automatically and quickly from archival satellite image data in response to requests from farmers. A farmer can make a request by either uploading data describing a field boundary to the Web site or else

75 FR 18144 - Kemmerer Ranger District, Bridger-Teton National Forest, Wyoming Kemmerer Grazing and Rangeland...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-09

..., Wyoming Kemmerer Grazing and Rangeland Vegetation Management Project AGENCY: Forest Service, USDA. ACTION... appropriate within the project area. If livestock grazing is re-authorized then the adaptive management... allowed to continue to graze on 16 allotments within the project area, and if so, under what management...

Effects of seasonal changes in feeding management under part-time grazing on terpene concentrations of ewes' milk.

PubMed

Abilleira, Eunate; Virto, Mailo; Nájera, Ana Isabel; Albisu, Marta; Pérez-Elortondo, Francisco José; Ruiz de Gordoa, Juan Carlos; de Renobales, Mertxe; Barron, Luis Javier R

2011-05-01

Terpene composition of ewes' raw milk from nine commercial flocks was analysed from February to July. Ewes' diet consisted of concentrate and conserved forage in winter (indoor feeding) and part-time grazing from spring (transition and outdoor feeding). Regardless of the feeding, limonene and β-phellandrene were the most abundant monoterpenes and β-caryophyllene showed the highest concentrations among sesquiterpenes. Terpene content increased in the milks of commercial flocks when animals were reared under grazing management. Monoterpenes were detected in the milks of all the commercial flocks throughout the season, whereas sesquiterpenes were only detected in the milks from flocks grazing on non-cultivated community-owned grasslands in which a higher biodiversity of plant species grew. These preliminary results indicated that β-caryophyllene could be a potential pasture-diet marker in the case of milks from animals grazing a higher biodiversity of plant species but in-depth studies including information on terpene composition of plants ingested by the animals are necessary to evaluate the suitability of β-caryophyllene or another terpenoid compound as pasture biomarker.

Bivalve grazing can shape phytoplankton communities

USGS Publications Warehouse

Lucas, Lisa; Cloern, James E.; Thompson, Janet K.; Stacey, Mark T.; Koseff, Jeffrey K.

2016-01-01

The ability of bivalve filter feeders to limit phytoplankton biomass in shallow waters is well-documented, but the role of bivalves in shaping phytoplankton communities is not. The coupled effect of bivalve grazing at the sediment-water interface and sinking of phytoplankton cells to that bottom filtration zone could influence the relative biomass of sinking (diatoms) and non-sinking phytoplankton. Simulations with a pseudo-2D numerical model showed that benthic filter feeding can interact with sinking to alter diatom:non-diatom ratios. Cases with the smallest proportion of diatom biomass were those with the fastest sinking speeds and strongest bivalve grazing rates. Hydrodynamics modulated the coupled sinking-grazing influence on phytoplankton communities. For example, in simulations with persistent stratification, the non-sinking forms accumulated in the surface layer away from bottom grazers while the sinking forms dropped out of the surface layer toward bottom grazers. Tidal-scale stratification also influenced vertical gradients of the two groups in opposite ways. The model was applied to Suisun Bay, a low-salinity habitat of the San Francisco Bay system that was transformed by the introduction of the exotic clam Potamocorbula amurensis. Simulation results for this Bay were similar to (but more muted than) those for generic habitats, indicating that P. amurensis grazing could have caused a disproportionate loss of diatoms after its introduction. Our model simulations suggest bivalve grazing affects both phytoplankton biomass and community composition in shallow waters. We view these results as hypotheses to be tested with experiments and more complex modeling approaches.

43 CFR 4710.5 - Closure to livestock grazing.

Code of Federal Regulations, 2011 CFR

2011-10-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) PROTECTION, MANAGEMENT, AND CONTROL OF WILD FREE-ROAMING HORSES AND BURROS Management Considerations § 4710.5 Closure to livestock grazing. (a) If...

43 CFR 4710.5 - Closure to livestock grazing.

Code of Federal Regulations, 2013 CFR

2013-10-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) PROTECTION, MANAGEMENT, AND CONTROL OF WILD FREE-ROAMING HORSES AND BURROS Management Considerations § 4710.5 Closure to livestock grazing. (a) If...

43 CFR 4710.5 - Closure to livestock grazing.

Code of Federal Regulations, 2014 CFR

2014-10-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) PROTECTION, MANAGEMENT, AND CONTROL OF WILD FREE-ROAMING HORSES AND BURROS Management Considerations § 4710.5 Closure to livestock grazing. (a) If...

43 CFR 4710.5 - Closure to livestock grazing.

Code of Federal Regulations, 2012 CFR

2012-10-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) PROTECTION, MANAGEMENT, AND CONTROL OF WILD FREE-ROAMING HORSES AND BURROS Management Considerations § 4710.5 Closure to livestock grazing. (a) If...

32 CFR 643.33 - Policy-Coastal zone management.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 4 2011-07-01 2011-07-01 false Policy-Coastal zone management. 643.33 Section... PROPERTY REAL ESTATE Policy § 643.33 Policy—Coastal zone management. (a) The Coastal Zone Management Act of... affecting the coastal zone of a state, to conduct or support those activities in a manner which is, to the...

32 CFR 643.33 - Policy-Coastal zone management.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 true Policy-Coastal zone management. 643.33 Section... PROPERTY REAL ESTATE Policy § 643.33 Policy—Coastal zone management. (a) The Coastal Zone Management Act of... affecting the coastal zone of a state, to conduct or support those activities in a manner which is, to the...

Soil organic matter stabilization in grazing highland soils from the Andean Plateau

NASA Astrophysics Data System (ADS)

Muñoz, M. A.; Faz, A.; Zornoza, R.

2012-04-01

Grasslands comprise approximately 40% of the earth's land area and play a critical role in the global carbon cycle. Apolobamba is a grazing highland located in the Andean Plateau where sustainable vicuna (Vicugna vicugna) management programme is carried out. Understanding the soil properties and the organic matter dynamics is fundamental to determine the grazing impacts in the carbon reservoirs. However, the labile and recalcitrant fractions of C have not been widely studied under field conditions, especially in high grasslands. The objectives of this survey were to: (i) achieve a soil characterization through general physico-chemical properties and (ii) study soil organic matter stabilization through recalcitrant and labile carbon budgets in Apolobamba. Regarding the lastly vicuna censuses carried out in the studied area, eight representative zones with different vicuna densities were selected and soil samples were collected. Other characteristics were also considered to select the study zones: (1) alpaca densities, (2) vegetation communities (3) plant cover and (4) landscape and geo-morphological description. Recalcitrant and water soluble organic carbon were determined as well as recalcitrant index. General soil characterization showed strongly acid and no saline soils with high cation exchange capacity and sandy-loam and loam textures. Total nitrogen contents indicated no limitation for the native vegetation growth. In general, no relationships were found among general soil properties, vicuna and alpaca densities; however, zones with highest alpaca density could be prone to soil erosion based on the available P distribution and the texture results. Additionally, a negative alpaca grazing influence in the soil organic carbon stocks was observed. On the other hand, high soil recalcitrant carbon contents (3.7 ± 0.3 kg m-2) and recalcitrance index (0.8 ± 0.1) were found. Likewise, labile C exhibited similar values to those obtained from researchers conducted in

Effects of grazing on nesting by upland sandpipers in southcentral North Dakota

USGS Publications Warehouse

Bowen, Bonnie S.; Kruse, Arnold D.

1993-01-01

Grazing by livestock is often used to reduce litter, improve plant vigor, and alter plant species composition, but additional information is needed on the effects of these management practices on upland-nesting birds. Thus, we conducted an experimental study of the effect of grazing on nest density and nest success of upland sandpipers (Bartramia longicauda) in southcentral North Dakota from 1981 to 1987. Our experimental design consisted of 4 treatments and 1 control, each applied to 1 field in each of 3 study areas. The treatments represented options available to grassland managers: spring grazing, autumn grazing, autumn-and-spring grazing, season-long grazing, and control (ungrazed during the study). Nests (n = 342) were found by searching study areas with a cable-chain drag. Nest density was lower (P = 0.006) for treatments where cattle were present (spring, autumn-and-spring, and season-long) than where cattle were not present (autumn and control) during the nesting season. We concluded that grazing during the nesting season reduced the nest density of upland sandpipers. Nest success varied among years (P = 0.01) and was low in the first year of grazing and higher at the end of the study period. We found little evidence that the grazing treatment influenced nest success. We recommend that public lands with breeding populations of upland sandpipers include a complex of fields under various management practices, including fields undisturbed during the nesting season.

Wildfire: It's Economic Impact on Grazing Livestock in Northern Nevada

NASA Astrophysics Data System (ADS)

Honeycutt, S.

2015-12-01

As the climate changes and Nevada experiences long severe drought, a key understanding of the economic impacts of wildfire on grazing livestock is essential in the assurance of livestock production in future management of Nevada's rangeland. The focus of this research is to determine the economic impact in the reduction of rangeland available for livestock grazing due to wildfires. The datasets utilized in this research are from 2007 & 2012 and include Bureau of Land Management wildfire, grazing allotments and herd management area geospatial data along with USDA Census of Agriculture, Inventory & Sales Information for cattle & calves, sheep & lambs, and goats. Presented in the results will be the direct, indirect, and induced economic effects of wildfires on rangeland production.

25 CFR 166.306 - Can the BIA adjust the grazing capacity?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Can the BIA adjust the grazing capacity? 166.306 Section 166.306 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING PERMITS Land and Operations Management § 166.306 Can the BIA adjust the grazing capacity? Yes. In consultation...

Effects of grazing management and buffer strips on metal runoff from pastures fertilized with poultry litter

USDA-ARS?s Scientific Manuscript database

Metal runoff from fields fertilized with poultry litter may pose a threat to aquatic systems. Buffer strips have been added to fields to reduce nutrients and solids runoff. However, scant information exists on the effects of buffer strips combined with grazing management strategies on metal runoff f...

Fall and spring grazing influence fire ignitability and initial spread in shrub steppe communities

USDA-ARS?s Scientific Manuscript database

The interaction between grazing and fire influences ecosystems around the world. However, relatively little is known about the influence of grazing on fire, in particular ignition and initial spread and how it varies by grazing management differences. We investigated effects of fall grazing, spring...

Estimating influence of stocking regimes on livestock grazing distributions

USDA-ARS?s Scientific Manuscript database

Ungulates often concentrate grazing at small hotspots in the larger landscape, and dispersing livestock away from these intensively grazed areas is one of the central challenges in range management. We evaluated a technique based on shifting the stocking date to prevent overgrazing of small areas co...

Micro-zooplankton grazing as a means of fecal bacteria removal in stormwater BMPs.

PubMed

Burtchett, Jade M; Mallin, Michael A; Cahoon, Lawrence B

2017-06-01

A priority for environmental managers is control of stormwater runoff pollution, especially fecal microbial pollution. This research was designed to determine if fecal bacterial grazing by micro-zooplankton is a significant control on fecal bacteria in aquatic best management practices (BMPs); if grazing differs between a wet detention pond and a constructed wetland; and if environmental factors enhance grazing. Both 3-day grazing tests and 24-h dilution assays were used to determine grazing differences between the two types of BMP. Micro-zooplankton grazing was a stronger bacteria removal mechanism in stormwater wetlands rich in aquatic vegetation compared to a standard wet detention pond, although grazing was important in detention ponds as well. Our experiments indicated that the majority of grazers that fed on fecal bacteria were <20 μm in size. Grazing rates were positively correlated with fecal coliform abundance and increased water temperatures. Enumeration of grazers demonstrated that protozoans were significantly more abundant among wetland vegetation than in open water, and open wetland waters contained more flagellates and dinoflagellates than open wet detention pond waters. Grazing on fecal bacteria in BMPs is enhanced by aquatic vegetation, and grazing in aquatic BMPs in warmer climates should be greater than in cooler climates.

49 CFR 1105.9 - Coastal Zone Management Act requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 8 2010-10-01 2010-10-01 false Coastal Zone Management Act requirements. 1105.9... ENVIRONMENTAL LAWS § 1105.9 Coastal Zone Management Act requirements. (a) If the proposed action affects land or water uses within a State coastal zone designated pursuant to the Coastal Zone Management Act (16 U.S.C...

49 CFR 1105.9 - Coastal Zone Management Act requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 8 2011-10-01 2011-10-01 false Coastal Zone Management Act requirements. 1105.9... ENVIRONMENTAL LAWS § 1105.9 Coastal Zone Management Act requirements. (a) If the proposed action affects land or water uses within a State coastal zone designated pursuant to the Coastal Zone Management Act (16 U.S.C...

SAMZ: Satellite-Derived Management Zones

NASA Technical Reports Server (NTRS)

2004-01-01

The term "satellite-derived management zones" (SAMZ) denotes agricultural management zones that are subdivisions of large fields and that are derived from images of the fields acquired by instruments aboard Earth orbiting satellites during approximately the past 15 years. "SAMZ" also denotes the methodology and the software that implements the methodology for creating such zones. The SAMZ approach is one of several products of continuing efforts to realize a concept of precision agriculture, which involves optimal variations in seeding, in application of chemicals, and in irrigation, plus decisions to farm or not to farm certain portions of fields, all in an effort to maximize profitability in view of spatial and temporal variations in the growth and health of crops and in the chemical and physical conditions of soils. As used here, "management zone" signifies, more precisely, a subdivision of a field within which the crop production behavior is regarded as homogeneous. From the perspective of precision agriculture, management zones are the smallest subdivisions between which the seeding, application of chemicals, and other management parameters are to be varied. In the SAMZ approach, the main sources of data are the archives of satellite imagery that have been collected over the years for diverse purposes. One of the main advantages afforded by the SAMZ approach is that the data in these archives can be reused for purposes of precision agriculture at low cost. De facto, these archives contain information on all sources of variability within a field, including weather, crop types, crop management, soil types, and water drainage patterns. The SAMZ methodology involves the establishment of a Web-based interface based on an algorithm that generates management zones automatically and quickly from archival satellite image data in response to requests from farmers. A farmer can make a request by either uploading data describing a field boundary to the Web site or else

Shaping the Herders' "Mental Maps": Participatory Mapping with Pastoralists' to Understand Their Grazing Area Differentiation and Characterization

NASA Astrophysics Data System (ADS)

Wario, Hussein T.; Roba, Hassan G.; Kaufmann, Brigitte

2015-09-01

Understanding the perception of environmental resources by the users is an important element in planning its sustainable use and management. Pastoralist communities manage their vast grazing territories and exploit resource variability through strategic mobility. However, the knowledge on which pastoralists' resource management is based and their perception of the grazing areas has received limited attention. To improve this understanding and to document this knowledge in a way that can be communicated with `outsiders', we adopted a participatory mapping approach using satellite imagery to explore how Borana pastoralists of southern Ethiopia differentiated and characterized their grazing areas. The Borana herders conceptualized their grazing areas as set of distinctive grazing units each having specific names and characteristics. The precise location and the borders of each grazing unit were identified on the satellite image. In naming of the grazing units, the main differentiating criteria were landforms, vegetation types, prevalence of wildlife species, and manmade features. Based on the dominant soil type, the grazing units were aggregated into seasonal grazing areas that were described using factors such as soil drainage properties, extent of woody cover, main grass species, and prevalence of ecto-parasites. Pastoralists ranking of the seasonal grazing areas according to their suitability for cattle grazing matched with vegetation assessment results on the abundance of desirable fodder varieties. Approaching grazing area differentiation from the pastoralists' perspectives improves the understanding of rangeland characteristics that pastoralists considered important in their grazing management and visualization of their mental representation in digital maps eases communication of this knowledge.

Annual methane budgets of sheep grazing systems were regulated by grazing intensities in the temperate continental steppe: A two-year case study

NASA Astrophysics Data System (ADS)

Ma, Lei; Zhong, Mengying; Zhu, Yuhao; Yang, Helong; Johnson, Douglas A.; Rong, Yuping

2018-02-01

Methane (CH4) emission from animal husbandry accounts for a large percentage of anthropogenic contributions to CH4 emissions. Fully understanding of grazing management effects on the CH4 budget is essential for mitigating CH4 emissions in the temperate grazing steppe systems. Annual CH4 budgets for the sheep grazed steppes at various grazing intensities, un-grazing (UG, 0 sheep ha-1year-1), defer grazing (DG, 1.0 sheep ha-1 year-1), moderate grazing (MG, 1.43 sheep ha-1year-1), and heavy grazing (HG, 2.43 sheep ha-1year-1) were assessed across 2012-2014 in the agro-pastoral region of northern China. Annual soil CH4 uptake averaged across 2012-2014 were 1.1 ± 0.1, 2.4 ± 0.2, 2.2 ± 0.2, and 1.3 ± 0.1 kg CH4-C ha-1 for UG, DG (only 2013-2014), MG and HG sites. Non-growing season CH4 uptake comprised 50.0 ± 4.3% of annual CH4 uptake in 2012-2013 and 37.7 ± 2.0% in 2013-2014. DG and MG significantly promoted annual soil CH4 uptake (P < 0.05), while there was no difference between HG and UG (P > 0.05). Bell-shaped relationship was presented between stocking rates and soil CH4 uptake (r2 = 0.59, P < 0.05). Annual soil CH4 uptake significant linearly and positively correlated with root biomass (r2 = 0.30, P < 0.05). Annual CH4 budgets for the grazed grasslands were -1.1 ± 0.1, 5.7 ± 0.6, 11.5 ± 1.5 and 15.5 ± 1.3 kg CH4-C ha-1 year-1 in UG, DG (only 2013-2014), MG and HG across 2012-2014. Soil CH4 uptake could offset 29.7 ± 5.6, 15.9 ± 4.3 and 6.8 ± 1.0% of total annual CH4 emissions from sheep, sheepfold and faeces in DG, MG, and HG. All grazed steppes are sources for atmospheric CH4 and the magnitude is regulated by grazing intensities. Sheep CH4 emissions for 1-g liveweight gain were 0.21, 0.32 and 0.37 g CH4-C in DG, MG and HG, respectively. DG is the recommended grazing management in this region to achieve greater herbage mass, higher sheep performance and lower CH4 emissions simultaneously.

A look at dairy mob grazing in the Northeast

USDA-ARS?s Scientific Manuscript database

Proponents of ultra-high stocking density (UHSD) grazing emphasize increased forage use efficiency and soil improvement by grazing mature forage with stocking densities up to 560,425 kg/ha of beef cattle on small paddocks with rest periods up to 125 days. However, it is unclear if this management te...

Phytoplankton growth balanced by clam and zooplankton grazing and net transport into the low-salinity zone of the San Francisco Estuary

USGS Publications Warehouse

Kimmerer, Wim J.; Thompson, Janet K.

2014-01-01

We estimated the influence of planktonic and benthic grazing on phytoplankton in the strongly tidal, river-dominated northern San Francisco Estuary using data from an intensive study of the low salinity foodweb in 2006–2008 supplemented with long-term monitoring data. A drop in chlorophyll concentration in 1987 had previously been linked to grazing by the introduced clam Potamocorbula amurensis, but numerous changes in the estuary may be linked to the continued low chlorophyll. We asked whether phytoplankton continued to be suppressed by grazing and what proportion of the grazing was by benthic bivalves. A mass balance of phytoplankton biomass included estimates of primary production and grazing by microzooplankton, mesozooplankton, and clams. Grazing persistently exceeded net phytoplankton growth especially for larger cells, and grazing by microzooplankton often exceeded that by clams. A subsidy of phytoplankton from other regions roughly balanced the excess of grazing over growth. Thus, the influence of bivalve grazing on phytoplankton biomass can be understood only in the context of limits on phytoplankton growth, total grazing, and transport.

Grazing effects on species composition in different vegetation types (La Palma, Canary Islands)

NASA Astrophysics Data System (ADS)

Arévalo, J. R.; de Nascimento, L.; Fernández-Lugo, S.; Mata, J.; Bermejo, L.

2011-05-01

Grazing management is probably one of the most extensive land uses, but its effects on plant communities have in many cases been revealed to be contradictory. Some authors have related these contradictions to the stochastic character of grazing systems. Because of that, it is necessary to implement specific analyses of grazing effects on each community, especially in natural protected areas, in order to provide the best information to managers. We studied the effects of grazing on the species composition of the main vegetation types where it takes place (grasslands, shrublands and pine forests) on the island of La Palma, Canary Islands. We used the point-quadrat intersect method to study the species composition of grazed and ungrazed areas, which also were characterized by their altitude, distance to farms, distance to settlements, year of sampling, herbaceous aboveground biomass and soil organic matter. The variables organic matter, productivity and species richness were not significantly affected by grazing. The species composition of the analyzed plant communities was affected more by variables such as altitude or distance to farms than by extensive grazing that has been traditionally carried out on the island of La Palma involving certain practices such as continuous monitoring of animals by goat keepers, medium stocking rates adjusted to the availability of natural pastures, supplementation during the dry season using local forage shrubs or mown pastures and rotating animals within grazing areas Although some studies have shown a negative effect of grazing on endangered plant species, these results cannot be freely extrapolated to the traditional grazing systems that exert a low pressure on plant communities (as has been found in this study). We consider extensive grazing as a viable way of ensuring sustainable management of the studied ecosystems.

Effects of grazing management treatment on grassland plant communities and prairie grouse habitat

Treesearch

Llewellyn L. Manske; William T. Barker; Mario E. Biondini

1988-01-01

Seasonlong grazing treatments show no benefit to grass basal cover and visual obstruction is not adequate. Pastures with one grazing period in mid season show no positive change in grass basal cover but have better visual obstruction than seasonlong. Deferred grazing decreases basal cover of warm season grasses and visual obstruction reduced to inadequate levels the...

Patterns in Greater Sage-grouse population dynamics correspond with public grazing records at broad scales.

PubMed

Monroe, Adrian P; Aldridge, Cameron L; Assal, Timothy J; Veblen, Kari E; Pyke, David A; Casazza, Michael L

2017-06-01

Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (Centrocercus urophasianus) as a model organism to evaluate responses to livestock management. With annual counts of male Sage-grouse from 743 leks (breeding display sites) during 2004-2014, we modeled population trends in response to grazing level (represented by a relative grazing index) and timing across a gradient in vegetation productivity as measured by the Normalized Vegetation Difference Index (NDVI). We found grazing can have both positive and negative effects on Sage-grouse populations depending on the timing and level of grazing. Sage-grouse populations responded positively to higher grazing levels after peak vegetation productivity, but populations declined when similar grazing levels occurred earlier, likely reflecting the sensitivity of cool-season grasses to grazing during peak growth periods. We also found support for the hypothesis that effects of grazing management vary with local vegetation productivity. These results illustrate the importance of broad-scale analyses by revealing patterns in Sage-grouse population trends that may not be inferred from studies at finer scales, and could inform sustainable grazing management in these ecosystems. © 2017 by the Ecological Society of America.

Patterns in Greater Sage-grouse population dynamics correspond with public grazing records at broad scales

USGS Publications Warehouse

Monroe, Adrian; Aldridge, Cameron L.; Assal, Timothy J.; Veblen, Kari E.; Pyke, David A.; Casazza, Michael L.

2017-01-01

Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (Centrocercus urophasianus) as a model organism to evaluate responses to livestock management. With annual counts of male Sage-grouse from 743 leks (breeding display sites) during 2004–2014, we modeled population trends in response to grazing level (represented by a relative grazing index) and timing across a gradient in vegetation productivity as measured by the Normalized Vegetation Difference Index (NDVI). We found grazing can have both positive and negative effects on Sage-grouse populations depending on the timing and level of grazing. Sage-grouse populations responded positively to higher grazing levels after peak vegetation productivity, but populations declined when similar grazing levels occurred earlier, likely reflecting the sensitivity of cool-season grasses to grazing during peak growth periods. We also found support for the hypothesis that effects of grazing management vary with local vegetation productivity. These results illustrate the importance of broad-scale analyses by revealing patterns in Sage-grouse population trends that may not be inferred from studies at finer scales, and could inform sustainable grazing management in these ecosystems.

25 CFR 166.301 - How is Indian land for grazing purposes described?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false How is Indian land for grazing purposes described? 166.301 Section 166.301 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING PERMITS Land and Operations Management § 166.301 How is Indian land for grazing purposes described...

Grasshopper fecundity responses to grazing and fire in a tallgrass prairie.

PubMed

Laws, Angela N; Joern, Anthony

2011-10-01

Grasshopper abundance and diversity vary with management practices such as fire and grazing. Understanding how grasshopper life history traits such as fecundity respond to management practices is key to predicting grasshopper population dynamics in heterogeneous environments. Landscape-level experimental fire and bison grazing treatments at the Konza Prairie Biological Station (Manhattan, KS) provide an opportunity to examine how management affects grasshopper fecundity. Here we report on grasshopper fecundity for nine common species at Konza Prairie. From 2007 to 2009, adult female grasshoppers were collected every 3 wk from eight watersheds that varied in fire and grazing treatments. Fecundity was measured by examining female reproductive tracts, which contain a record of past and current reproductive activity. Body size was a poor predictor of fecundity for all species. Despite large differences in vegetation structure and composition with management regime (grazing and fire interval), we observed little effect of management on grasshopper fecundity. Habitat characteristics (grasshopper density, vegetation biomass, and vegetation quality; measured in 2008 and 2009) were better predictors of past fecundity than current fecundity, with species-specific responses. Fecundity increased throughout the summer, indicating that grasshoppers were able to acquire sufficient nutritional resources for egg production in the early fall when vegetation quality is generally low. Because fecundity did not vary across management treatments, population stage structure may be more important for determining population level reproduction than management regime at Konza Prairie.

Consequences of prescribed fire and grazing on grassland ant communities.

PubMed

Underwood, Emma C; Christian, Caroline E

2009-04-01

Prescribed fire and livestock grazing are used for the management and restoration of native grasslands the world over; however, the effects of these management techniques on ant communities are unclear. We examined the response of ants to these disturbances in grasslands in northern California. Twenty-four 30 by 30 m plots were established across two sites that received one of four treatments: grazing, fire, grazing and fire, or no treatment. Ants were censused using 240 pitfall traps with one preburn and two postburn samples (14 d and 1 yr after burning). We analyzed ant abundance using broadly defined groups based on feeding habit and/or habitat use and detected no grazing effect but a significant fire effect that differed by group. Immediate postfire sampling showed an increase in cryptic species (particularly Brachymyrmex depilis). One year after the fire, no response was detected for cryptic species, but burned plots had greater abundance of seed harvesters. Analysis of vegetation showed burned plots had significantly greater forb cover, which might have provided greater food resources, and also lower biomass, which might have facilitated foraging. Understanding the effects of these management tools on ant abundance complements our understanding of their effect on vegetation and assists conservation practitioners effectively manage grassland ecosystems both in California and beyond.

Revealing livestock effects on bunchgrass vegetation with Landsat ETM+ data across a grazing season

NASA Astrophysics Data System (ADS)

Jansen, Vincent S.

Remote sensing provides monitoring solutions for more informed grazing management. To investigate the ability to detect the effects of cattle grazing on bunchgrass vegetation with Landsat Enhanced Thematic Mapper Plus (ETM+) data, we conducted a study on the Zumwalt Prairie in northeastern Oregon across a gradient of grazing intensities. Biophysical vegetation data was collected on vertical structure, biomass, and cover at three different time periods during the grazing season: June, August, and October 2012. To relate these measures to the remotely sensed Landsat ETM+ data, Pearson's correlations and multiple regression models were computed. Using the best models, predicted vegetation metrics were then mapped across the study area. Results indicated that models using common vegetation indices had the ability to discern different levels of grazing across the study area. Results can be distributed to land managers to help guide grassland conservation by improving monitoring of bunchgrass vegetation for sustainable livestock management.

Influence of forest and rangeland management on anadromous fish habitat in Western North America: effects of livestock grazing.

Treesearch

William S. Platts

1981-01-01

This paper documents current knowledge on interactions of livestock and fish habitat. Included are discussions of incompatibility and compatibility between livestock grazing and fisheries, present management guidelines, information needed for problem solving, information available for problem solving, and future research needs.

Grazing effects on carbon fluxes in a northern China grassland

USDA-ARS?s Scientific Manuscript database

Grazing is a widespread use of grasslands in northern China, but if stocking rate exceeds grassland carrying capacity, degradation and desertification can occur. As a result, grazing management is critical and can play a significant role in driving C sink and source activity in grassland ecosystems...

Grazing limits natural biological controls of woody encroachment in Inner Mongolia Steppe.

PubMed

Guo, Hongyu; Guan, Linjing; Wang, Yinhua; Xie, Lina; Prather, Chelse M; Liu, Chunguang; Ma, Chengcang

2017-10-15

Woody encroachment in grasslands has become increasingly problematic globally. Grazing by domestic animals can facilitate woody encroachment by reducing competition from herbaceous plants and fire frequency. Herbivorous insects and parasitic plants can each exert forces that result in the natural biological control of encroaching woody plants through reducing seeding of their host woody plants. However, the interplay of grazing and dynamics of herbivorous insects or parasitic plants, and its effects on the potential biological control of woody encroachment in grasslands remains unclear. We investigated the flower and pod damage by herbivorous insects, and the infection rates of a parasitic plant on the shrub Caragana microphylla , which is currently encroaching in Inner Mongolia Steppe, under different grazing management treatments (33-year non-grazed, 7-year non-grazed, currently grazed). Our results showed that Caragana biomass was highest at the currently grazed site, and lowest at the 33-year non-grazed site. Herbaceous plant biomass followed the opposite pattern, suggesting that grazing is indeed facilitating the encroachment of Caragana plants in Inner Mongolia Steppe. Grazing also reduced the abundance of herbivorous insects per Caragana flower, numbers of flowers and pods damaged by insect herbivores, and the infection rates of the parasitic plant on Caragana plants. Our results suggest that grazing may facilitate woody encroachment in grasslands not only through canonical mechanisms (e.g. competitive release via feeding on grasses, reductions in fires, etc.), but also by limiting natural biological controls of woody plants (herbivorous insects and parasitic plants). Thus, management efforts must focus on preventing overgrazing to better protect grassland ecosystems from woody encroachment. © 2017. Published by The Company of Biologists Ltd.

Grazing limits natural biological controls of woody encroachment in Inner Mongolia Steppe

PubMed Central

Guo, Hongyu; Guan, Linjing; Wang, Yinhua; Xie, Lina; Prather, Chelse M.; Liu, Chunguang

2017-01-01

ABSTRACT Woody encroachment in grasslands has become increasingly problematic globally. Grazing by domestic animals can facilitate woody encroachment by reducing competition from herbaceous plants and fire frequency. Herbivorous insects and parasitic plants can each exert forces that result in the natural biological control of encroaching woody plants through reducing seeding of their host woody plants. However, the interplay of grazing and dynamics of herbivorous insects or parasitic plants, and its effects on the potential biological control of woody encroachment in grasslands remains unclear. We investigated the flower and pod damage by herbivorous insects, and the infection rates of a parasitic plant on the shrub Caragana microphylla, which is currently encroaching in Inner Mongolia Steppe, under different grazing management treatments (33-year non-grazed, 7-year non-grazed, currently grazed). Our results showed that Caragana biomass was highest at the currently grazed site, and lowest at the 33-year non-grazed site. Herbaceous plant biomass followed the opposite pattern, suggesting that grazing is indeed facilitating the encroachment of Caragana plants in Inner Mongolia Steppe. Grazing also reduced the abundance of herbivorous insects per Caragana flower, numbers of flowers and pods damaged by insect herbivores, and the infection rates of the parasitic plant on Caragana plants. Our results suggest that grazing may facilitate woody encroachment in grasslands not only through canonical mechanisms (e.g. competitive release via feeding on grasses, reductions in fires, etc.), but also by limiting natural biological controls of woody plants (herbivorous insects and parasitic plants). Thus, management efforts must focus on preventing overgrazing to better protect grassland ecosystems from woody encroachment. PMID:28912357

Response of soil methane uptake to simulated nitrogen deposition and grazing management across three types of steppe in Inner Mongolia, China.

PubMed

Li, Xianglan; He, Hong; Yuan, Wenping; Li, Linghao; Xu, Wenfang; Liu, Wei; Shi, Huiqiu; Hou, Longyu; Chen, Jiquan; Wang, Zhiping

2018-01-15

The response of soil methane (CH 4 ) uptake to increased nitrogen (N) deposition and grazing management was studied in three types of steppe (i.e., meadow steppe, typical steppe, and desert steppe) in Inner Mongolia, China. The experiment was designed with four simulated N deposition rates such as 0, 50, 100, and 200kgNha -1 , respectively, under grazed and fenced management treatments. Results showed that the investigated steppes were significant sinks for CH 4 , with an uptake flux of 1.12-3.36kgha -1 over the grass growing season and that the magnitude of CH 4 uptake significantly (P<0.05) decreased with increasing N deposition rates. The soil CH 4 uptake rates were highest in the desert steppe, moderate in the typical steppe, and lowest in the meadow steppe. Compared with grazed plots, fencing increased the CH 4 uptake by 4.7-40.2% with a mean value of 20.2% across the three different steppe types. The responses of soil CH 4 uptake to N deposition in the continental steppe varied depending on the N deposition rate, steppe type, and grazing management. A significantly positive correlation between CH 4 uptake and soil temperature was found in this study, whereas no significant relationship between soil moisture and CH 4 uptake occurred. Our results may contribute to the improvement of model parameterization for simulating biosphere-atmosphere CH 4 exchange processes and for evaluating the climate change feedback on CH 4 soil uptake. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of grazing on methane uptake from Eurasian steppe of China.

PubMed

Tang, Shiming; Zhang, Yujuan; Zhai, Xiajie; Wilkes, Andreas; Wang, Chengjie; Wang, Kun

2018-03-20

The effects of grazing on soil methane (CH 4 ) uptake in steppe ecosystems are important for understanding carbon sequestration and cycling because the role of grassland soil for CH 4 uptake can have major impacts at the global level. Here, a meta-analysis of 27 individual studies was carried out to assess the response patterns of soil CH 4 uptake to grazing in steppe ecosystems of China. The weighted log response ratio was used to assess the effect size. We found that heavy grazing significantly depressed soil CH 4 uptake by 36.47%, but light and moderate grazing had no significant effects in grassland ecosystem. The response of grassland soil CH 4 uptake to grazing also was found to depend upon grazing intensity, grazing duration and climatic types. The increase in soil temperature and reduced aboveground biomass and soil moisture induced by heavy grazing may be the major regulators of the soil CH 4 uptake. These findings imply that grazing effects on soil CH 4 uptake are highly context-specific and that grazing in different grasslands might be managed differently to help mitigate greenhouse gas emissions.

Relative importance of management, meteorological and environmental factors in the spatial distribution of Fasciola hepatica in dairy cattle in a temperate climate zone.

PubMed

Bennema, S C; Ducheyne, E; Vercruysse, J; Claerebout, E; Hendrickx, G; Charlier, J

2011-02-01

Fasciola hepatica, a trematode parasite with a worldwide distribution, is the cause of important production losses in the dairy industry. Diagnosis is hampered by the fact that the infection is mostly subclinical. To increase awareness and develop regionally adapted control methods, knowledge on the spatial distribution of economically important infection levels is needed. Previous studies modelling the spatial distribution of F. hepatica are mostly based on single cross-sectional samplings and have focussed on climatic and environmental factors, often ignoring management factors. This study investigated the associations between management, climatic and environmental factors affecting the spatial distribution of infection with F. hepatica in dairy herds in a temperate climate zone (Flanders, Belgium) over three consecutive years. A bulk-tank milk antibody ELISA was used to measure F. hepatica infection levels in a random sample of 1762 dairy herds in the autumns of 2006, 2007 and 2008. The infection levels were included in a Geographic Information System together with meteorological, environmental and management parameters. Logistic regression models were used to determine associations between possible risk factors and infection levels. The prevalence and spatial distribution of F. hepatica was relatively stable, with small interannual differences in prevalence and location of clusters. The logistic regression model based on both management and climatic/environmental factors included the factors: annual rainfall, mowing of pastures, proportion of grazed grass in the diet and length of grazing season as significant predictors and described the spatial distribution of F. hepatica better than the model based on climatic/environmental factors only (annual rainfall, elevation and slope, soil type), with an Area Under the Curve of the Receiver Operating Characteristic of 0.68 compared with 0.62. The results indicate that in temperate climate zones without large climatic

Carbon budgets for an irrigated intensively grazed dairy pasture and an unirrigated winter-grazed pasture

NASA Astrophysics Data System (ADS)

Hunt, John E.; Laubach, Johannes; Barthel, Matti; Fraser, Anitra; Phillips, Rebecca L.

2016-05-01

Intensification of pastoral agriculture is occurring rapidly across New Zealand, including increasing use of irrigation and fertiliser application in some regions. While this enables greater gross primary production (GPP) and livestock grazing intensity, the consequences for the net ecosystem carbon budget (NECB) of the pastures are poorly known. Here, we determined the NECB over one year for an irrigated, fertilised and rotationally grazed dairy pasture and a neighbouring unirrigated, unfertilised, winter-grazed pasture. Primary terms in the NECB calculation were: net ecosystem production (NEP), biomass carbon removed by grazing cows and carbon (C) input from their excreta. Annual NEP was measured using the eddy-covariance method. Carbon removal was estimated with plate-meter measurements calibrated against biomass collections, pre- and post-grazing. Excreta deposition was calculated from animal feed intake. The intensively managed pasture gained C (NECB = 103 ± 42 g C m-2 yr-1) but would have been subject to a non-significant C loss if cattle excreta had not been returned to the pasture. The unirrigated pasture was C-neutral (NECB = -13 ± 23 g C m-2 yr-1). While annual GPP of the former was almost twice that of the latter (2679 vs. 1372 g C m-2 yr-1), ecosystem respiration differed by only 68 % between the two pastures (2271 vs. 1352 g C m-2 yr-1). The ratio of GPP to the total annual water input of the irrigated pasture was 37 % greater than that of the unirrigated pasture, i.e. the former used the water input more efficiently than the latter to produce biomass. The NECB results agree qualitatively with those from many other eddy-covariance studies of grazed grasslands, but they seem to be at odds with long-term carbon-stock studies of other New Zealand pastures.

Dairy farmers using mob grazing in Pennsylvania and New York

USDA-ARS?s Scientific Manuscript database

Proponents of ultra-high stocking density grazing emphasize increased forage use efficiency and soil improvement by grazing mature forage with stocking densities up to 500,000 lb per acre of beef cattle on small paddocks with rest periods up to 180 days. However, it is unclear if this management tec...

Restoration of the fire-grazing interaction in Artemisia filifolia shrubland

USGS Publications Warehouse

Winter, S.L.; Fuhlendorf, S.D.; Goad, C.L.; Davis, C.A.; Hickman, K.R.; Leslie, David M.

2012-01-01

Patterns of landscape heterogeneity are crucial to the maintenance of biodiversity in shrublands and grasslands, yet management practices in these ecosystems typically seek to homogenize landscapes. Furthermore, there is limited understanding of how the interaction of ecological processes, such as fire and grazing, affects patterns of heterogeneity at different spatial scales. We conducted research in Artemisia filifolia (Asteraceae) shrublands located in the southern Great Plains of North America to determine the effect of restoring the fire-grazing interaction on vegetation structure. Data were collected for 3years in replicated pastures grazed by cattle Bos taurus where the fire-grazing interaction had been restored (fire and grazing=treatment pastures) and in pastures that were grazed but remained unburned (grazing only, no fire=control pastures). The effect of the fire-grazing interaction on heterogeneity (variance) of vegetation structure was assessed at scales from 12??5m 2 to 609ha. Most measurements of vegetation structure within treatment pastures differed from control pastures for 1-3years after being burned but were thereafter similar to the values found in unburned control pastures. Treatment pastures were characterized by a lower amount of total heterogeneity and a lower amount of heterogeneity through time. Heterogeneity of vegetation structure tended to decrease as the scale of measurement increased in both treatment and control pastures. There was deviation from this trend, however, in the treatment pastures that exhibited much higher heterogeneity at the patch scale (mean patch size=202ha) of measurement, the scale at which patch fires were conducted. Synthesis and applications.Vegetation structure in A. filifolia shrublands of our study was readily altered by the fire-grazing interaction but also demonstrated substantial resilience to these effects. The fire-grazing interaction also changed the total amount of heterogeneity characterizing this

Using Social Media to Discover Public Values, Interests, and Perceptions about Cattle Grazing on Park Lands

NASA Astrophysics Data System (ADS)

Barry, Sheila J.

2014-02-01

In the western United States, livestock grazing often co-exists with recreation, cultural resource management and biodiversity protection on federal and state protected rangelands as well as on many local government open space areas. While the value of livestock grazing for managing rangeland vegetation to reduce fire fuel loads and improve wildlife habitat is increasingly recognized by resource management professionals, public concerns, and conflict between recreationist and livestock have led to reductions in public land grazing. Traditional public input methods yield a constrained picture of people's attitudes toward cows and public land grazing. Public meetings, hearings, and surveys, the most commonly used mechanisms for public land managers to solicit public opinion, tend to foster participation of organized special interests or, in the case of surveys, focus on a specific topic. General public input is limited. This study explored the use of personal photography in social media to gain insight into public perceptions of livestock grazing in public spaces. Key findings of this study include that many recreationist in grazed San Francisco Bay Area parks shared views, interests, and concerns about cows and grazing on the photo-sharing website, FlickrTM that seldom show up at a public meeting or in surveys. Results suggest that social media analysis can help develop a more nuanced understanding of public viewpoints useful in making decisions and creating outreach and education programs for public grazing lands. This study demonstrates that using such media can be useful in gaining an understanding of public concerns about natural resource management.

Issues in Coastal Zone Management.

ERIC Educational Resources Information Center

Davis, Derrin

1992-01-01

Addresses the following issues relevant to coastal zone management: overcrowding, resource exploitation, pollution, agriculture, fisheries, industrial, and other uses. Describes conflicts and trade-offs in management typified by fragmented agency decision making. Discusses implications of the greenhouse effect, sustainable development, and the…

The effects of burning and grazing on soil carbon dynamics in managed Peruvian tropical montane grasslands

NASA Astrophysics Data System (ADS)

Oliver, Viktoria; Oliveras, Imma; Kala, Jose; Lever, Rebecca; Arn Teh, Yit

2017-12-01

Montane tropical soils are a large carbon (C) reservoir, acting as both a source and a sink of CO2. Enhanced CO2 emissions originate, in large part, from the decomposition and losses of soil organic matter (SOM) following anthropogenic disturbances. Therefore, quantitative knowledge of the stabilization and decomposition of SOM is necessary in order to understand, assess and predict the impact of land management in the tropics. In particular, labile SOM is an early and sensitive indicator of how SOM responds to changes in land use and management practices, which could have major implications for long-term carbon storage and rising atmospheric CO2 concentrations. The aim of this study was to investigate the impacts of grazing and fire history on soil C dynamics in the Peruvian montane grasslands, an understudied ecosystem, which covers approximately a quarter of the land area in Peru. A density fractionation method was used to quantify the labile and stable organic matter pools, along with soil CO2 flux and decomposition measurements. Grazing and burning together significantly increased soil CO2 fluxes and decomposition rates and reduced temperature as a driver. Although there was no significant effect of land use on total soil C stocks, the combination of burning and grazing decreased the proportion of C in the free light fraction (LF), especially at the lower depths (10-20 and 20-30 cm). In the control soils, 20 % of the material recovered was in the free LF, which contained 30 % of the soil C content. In comparison, the burnt-grazed soil had the smallest recovery of the free LF (10 %) and a significantly lower C content (14 %). The burnt soils had a much higher proportion of C in the occluded LF (12 %) compared to the not-burnt soils (7 %) and there was no significant difference among the treatments in the heavy fraction (F) ( ˜ 70 %). The synergistic effect of burning and grazing caused changes to the soil C dynamics. CO2 fluxes were increased and the dominant

Is grazing exclusion effective in restoring vegetation in degraded alpine grasslands in Tibet, China?

PubMed Central

Yan, Yan

2015-01-01

Overgrazing is considered one of the key disturbance factors that results in alpine grassland degradation in Tibet. Grazing exclusion by fencing has been widely used as an approach to restore degraded grasslands in Tibet since 2004. Is the grazing exclusion management strategy effective for the vegetation restoration of degraded alpine grasslands? Three alpine grassland types were selected in Tibet to investigate the effect of grazing exclusion on plant community structure and biomass. Our results showed that species biodiversity indicators, including the Pielou evenness index, the Shannon–Wiener diversity index, and the Simpson dominance index, did not significantly change under grazing exclusion conditions. In contrast, the total vegetation cover, the mean vegetation height of the community, and the aboveground biomass were significantly higher in the grazing exclusion grasslands than in the free grazed grasslands. These results indicated that grazing exclusion is an effective measure for maintaining community stability and improving aboveground vegetation growth in alpine grasslands. However, the statistical analysis showed that the growing season precipitation (GSP) plays a more important role than grazing exclusion in which influence on vegetation in alpine grasslands. In addition, because the results of the present study come from short term (6–8 years) grazing exclusion, it is still uncertain whether these improvements will be continuable if grazing exclusion is continuously implemented. Therefore, the assessments of the ecological effects of the grazing exclusion management strategy on degraded alpine grasslands in Tibet still need long term continued research. PMID:26157607

Is grazing exclusion effective in restoring vegetation in degraded alpine grasslands in Tibet, China?

PubMed

Yan, Yan; Lu, Xuyang

2015-01-01

Overgrazing is considered one of the key disturbance factors that results in alpine grassland degradation in Tibet. Grazing exclusion by fencing has been widely used as an approach to restore degraded grasslands in Tibet since 2004. Is the grazing exclusion management strategy effective for the vegetation restoration of degraded alpine grasslands? Three alpine grassland types were selected in Tibet to investigate the effect of grazing exclusion on plant community structure and biomass. Our results showed that species biodiversity indicators, including the Pielou evenness index, the Shannon-Wiener diversity index, and the Simpson dominance index, did not significantly change under grazing exclusion conditions. In contrast, the total vegetation cover, the mean vegetation height of the community, and the aboveground biomass were significantly higher in the grazing exclusion grasslands than in the free grazed grasslands. These results indicated that grazing exclusion is an effective measure for maintaining community stability and improving aboveground vegetation growth in alpine grasslands. However, the statistical analysis showed that the growing season precipitation (GSP) plays a more important role than grazing exclusion in which influence on vegetation in alpine grasslands. In addition, because the results of the present study come from short term (6-8 years) grazing exclusion, it is still uncertain whether these improvements will be continuable if grazing exclusion is continuously implemented. Therefore, the assessments of the ecological effects of the grazing exclusion management strategy on degraded alpine grasslands in Tibet still need long term continued research.

The effects of timing of grazing on plant and arthropod communities in high-elevation grasslands.

PubMed

Davis, Stacy C; Burkle, Laura A; Cross, Wyatt F; Cutting, Kyle A

2014-01-01

Livestock grazing can be used as a key management tool for maintaining healthy ecosystems. However, the effectiveness of using grazing to modify habitat for species of conservation concern depends on how the grazing regime is implemented. Timing of grazing is one grazing regime component that is less understood than grazing intensity and grazer identity, but is predicted to have important implications for plant and higher trophic level responses. We experimentally assessed how timing of cattle grazing affected plant and arthropod communities in high-elevation grasslands of southwest Montana to better evaluate its use as a tool for multi-trophic level management. We manipulated timing of grazing, with one grazing treatment beginning in mid-June and the other in mid-July, in two experiments conducted in different grassland habitat types (i.e., wet meadow and upland) in 2011 and 2012. In the upland grassland experiment, we found that both early and late grazing treatments reduced forb biomass, whereas graminoid biomass was only reduced with late grazing. Grazing earlier in the growing season versus later did not result in greater recovery of graminoid or forb biomass as expected. In addition, the density of the most ubiquitous grassland arthropod order (Hemiptera) was reduced by both grazing treatments in upland grasslands. A comparison of end-of-season plant responses to grazing in upland versus wet meadow grasslands revealed that grazing reduced graminoid biomass in the wet meadow and forb biomass in the upland, irrespective of timing of grazing. Both grazing treatments also reduced end-of-season total arthropod and Hemiptera densities and Hemiptera biomass in both grassland habitat types. Our results indicate that both early and late season herbivory affect many plant and arthropod characteristics in a similar manner, but grazing earlier may negatively impact species of conservation concern requiring forage earlier in the growing season.

Woodlands Grazing Issues in Mediterranean Basin

NASA Astrophysics Data System (ADS)

Campos, P.

2009-04-01

In Mediterranean basin, woodlands grazing still continue to be important commercial owners' benefits. These owners manage woodlands vegetations as if they were not at risk of degradation and declining. Frequently, no temporally grazing set-aside is taken into account to avoid overgrazing of annual and perennial vegetations. Although less common, in the northern shore of Mediterranean basin undergrazing might increase the frequency and the number of catastrophic forest fires. This under/over grazing regime occurs in the Mediterranean basin woodlands with contrasted differences on land property rights, local economies and government livestock policy incentives. Spain and Tunisia are examples of these Mediterranean livestock contrasts. Most of Spanish Mediterranean woodlands and livestock herds are large private ownerships and owners could maintain their lands and livestock herds properties on the basis of moderate cash-income compensation against land revaluation and exclusive amenity self-consumption. The later is less tangible benefit and it could include family land legacy, nature enjoyment, country stile of life development, social status and so on. In public woodlands, social and environmental goals -as they are cultural heritage, biodiversity loss mitigation, soil conservation and employment- could maintain market unprofitable woodlands operations. Last three decades Spanish Mediterranean woodlands owners have increased the livestock herds incentivized by government subsidies. As result, grazing rent is pending on the level of European Union and Spanish government livestock subsidies. In this context, Spanish Mediterranean woodlands maintain a high extensive livestock stoking population, which economy could be called fragile and environmentally unsustainable because forest degradation and over/under grazing practices. Tunisian Mediterranean woodlands are state properties and livestock grazing is practice as a free private regimen. Livestock herds are small herd

[Effects of grazing on zoobenthos community in beach].

PubMed

Zhao, Yun-long; An, Chuan-guang; Lin, Ling; Duan, Xiao-wei; Zeng, Cuo; Cui, Li-li

2007-05-01

In May (spring) and October (autumn) 2005, the effects of grazing on the zoobenthos community in Chongming Dongtan wetland of Shanghai were investigated. A total of 3 transects including 90 sampling plots were set up. Transects I and II were in feeding area, and transect III was in non-pasture area. All of these three transects were set in mid-tidal zone. 13 zoobenthos species were observed, with 7 species of arthropod, 4 species of mollusk, and 2 species of annelid. In spring, there were 6, 8 and 10 species in transects I , II and III while in autumn, the species number was 6, 8 and 12, respectively. The mean abundance of zoobenthos community in all transects was higher in autumn than in spring, and transect III had the highest mean abundance and biomass both in autumn and spring. Transect III also had the highest evenness, richness and diversity, indicating that grazing could change the species distribution of zoobenthos, and affect their abundance and biomass to different degree. Grazing had made certain negative effects on the biodiversity of zoobenthos community in Chongming Dongtan wetland.

Characterizing Manatee habitat use and seagrass grazing in Florida and Puerto Rico: Implications for conservation and management

USGS Publications Warehouse

Lefebvre, L.W.; Reid, J.P.; Kenworthy, W.J.; Powell, J.A.

2000-01-01

The Indian River Lagoon on the Atlantic coast of Florida, USA, and the east coast of Puerto Rico provide contrasting environments in which the endangered West Indian Manatee Trichechus manatus experiences different thermal regimes and seagrass communities. We compare Manatee feeding behaviour in these two regions, examine the ecological effects of Manatee grazing on a seagrass community in the Indian River Lagoon, describe the utility of aerial surveys, radio tracking, and seagrass mapping to study Manatee feeding patterns, and develop hypotheses on sirenian feeding strategies in temperate and tropical seagrass communities. In both the Indian River Lagoon and Puerto Rico, Manatees were typically observed grazing in water depths = 2.0 m and more frequently on the most abundant seagrasses present in the community: Halodule wrightii in the Indian River Lagoon and Thalassia testudinum in eastern Puerto Rico. Where both H. wrightii and Syringodium filiforme were consumed in the Indian River Lagoon, Manatees tended to remove more S. filiforme than H. wrightii rhizome + root biomass. Even though 80 to 95% of the short-shoot biomass and 50 to 67% of the rhizome + root biomass were removed, grazed patches of H. wrightii and S. filiforme recovered significantly between February and August. H. wrightii may be both more resistant and resilient than S. filiforme to the impacts of Manatee grazing. Despite the significantly greater abundance of T. testudinum in Puerto Rico, Manatees exhibited selective feeding by returning to specific sites with abundant H. wrightii. They also appeared to feed selectively on T. testudinum shoots associated with clumps of the calcareous alga Halimeda opuntia. We hypothesize that Florida Manatees are less specialized seagrass grazers than Manatees in tropical regions like Puerto Rico. Continued research on Manatee grazing ecology in temperate to tropical seagrass communities will enable better protection and management of these vital and unique

30 CFR 256.20 - Consideration of coastal zone management program.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Consideration of coastal zone management....20 Consideration of coastal zone management program. In the development of the leasing program, consideration shall be given to the coastal zone management program being developed or administered by an...

Combined effects of climatic gradient and domestic livestock grazing on reptile community structure in a heterogeneous agroecosystem.

PubMed

Rotem, Guy; Gavish, Yoni; Shacham, Boaz; Giladi, Itamar; Bouskila, Amos; Ziv, Yaron

2016-01-01

Grazing plays an important role in shaping ecological communities in human-related ecosystems. Although myriad studies have explored the joint effect of grazing and climate on plant communities, this interactive effect has rarely been studied in animals. We hypothesized that the effect of grazing on the reptile community varies along a climatic gradient in relation to the effect of grazing on habitat characteristics, and that grazing differentially affects reptiles of different biogeographic regions. We tested our hypotheses by collecting data on environmental characteristics and by trapping reptiles in four heterogeneous landscapes experiencing differing grazing intensities and distributed along a sharp climatic gradient. We found that while reptile diversity increased with grazing intensity at the mesic end of the gradient, it decreased with grazing intensity at the arid end. Moreover, the proportion of reptile species of differing biogeographic origins varied with the interactive effect of climate and grazing. The representation of species originating in arid biogeographic zones was highest at the arid end of the climatic gradient, and representation increased with grazing intensity within this area. Regardless of the climatic context, increased grazing pressure results in a reduction in vegetation cover and thus in changes in habitat characteristics. By reducing vegetation cover, grazing increased habitat heterogeneity in the dense mesic sites and decreased habitat heterogeneity in the arid sites. Thus, our results suggest that the same direction of habitat alteration caused by grazing may have opposite effects on biodiversity and community composition in different climatic contexts.

An Efficient Method for Detecting Misbehaving Zone Manager in MANET

NASA Astrophysics Data System (ADS)

Rafsanjani, Marjan Kuchaki; Pakzad, Farzaneh; Asadinia, Sanaz

In recent years, one of the wireless technologies increased tremendously is mobile ad hoc networks (MANETs) in which mobile nodes organize themselves without the help of any predefined infrastructure. MANETs are highly vulnerable to attack due to the open medium, dynamically changing network topology, cooperative algorithms, lack of centralized monitoring, management point and lack of a clear defense line. In this paper, we report our progress in developing intrusion detection (ID) capabilities for MANET. In our proposed scheme, the network with distributed hierarchical architecture is partitioned into zones, so that in each of them there is one zone manager. The zone manager is responsible for monitoring the cluster heads in its zone and cluster heads are in charge of monitoring their members. However, the most important problem is how the trustworthiness of the zone manager can be recognized. So, we propose a scheme in which "honest neighbors" of zone manager specify the validation of their zone manager. These honest neighbors prevent false accusations and also allow manager if it is wrongly misbehaving. However, if the manger repeats its misbehavior, then it will lose its management degree. Therefore, our scheme will be improved intrusion detection and also provide a more reliable network.

Bison grazing ecology at the Rocky Mountain Arsenal National Wildlife Refuge, Colorado

USGS Publications Warehouse

Germaine, Stephen S.; Zeigenfuss, Linda C.; Schoenecker, Kathryn A.

2013-01-01

The Rocky Mountain Arsenal (RMA) National Wildlife Refuge reintroduced bison to a small pasture in 2007. Refuge managers needed information on the effects of bison grazing on vegetation communities in the bison pasture as well as information on how bison might affect other management priorities at RMA. In particular, RMA managers were interested in bison grazing effects on vegetation productivity, amount of vegetation utilization by bison, and habitat selection by bison to inform RMA herd managers and for potential expansion of bison range on the refuge. In 2007, U.S. Geological Survey (USGS) designed a study to investigate bison grazing effects through measurement of vegetation in the 600-hectare enclosure where the bison are currently pastured. This research was a collaborative effort between USGS and RMA refuge staff and had active field components in 2007 and 2010. We found that the effects and intensity of bison grazing on vegetation in the RMA bison pasture is linked to prairie dog presence. Where both species were present, they were removing a significant amount of biomass compared to areas where only bison were present. Also, prairie dogs appeared to enhance the greater production of native forbs, but we were not able to identify the mechanism for this increased production. We were not able, however, to generate an accurate vegetation map for the bison pasture, and this limited our ability to achieve the level of statistical precision necessary to identify grazing impacts and habitat selection of bison.

30 CFR 256.20 - Consideration of coastal zone management program.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Consideration of coastal zone management... SHELF Oil and Gas Leasing Program § 256.20 Consideration of coastal zone management program. In the development of the leasing program, consideration shall be given to the coastal zone management program being...

Grazing and Land Management Strategies for Hardwood Rangelands

Treesearch

Melvin R. George

1991-01-01

Annual rangelands produce 84 percent of California's range forage which are used all year by sedentary ranching operations and seasonally by migratory operations. Environmental policy, energy and water costs may reduce traditional summer forage sources, resulting in increased grazing pressure on hardwood and annual rangelands. However, the landowner's...

In situ grazing experiments apply new technology to gain insights into deep-sea microbial food webs

NASA Astrophysics Data System (ADS)

Pachiadaki, Maria G.; Taylor, Craig; Oikonomou, Andreas; Yakimov, Michail M.; Stoeck, Thorsten; Edgcomb, Virginia

2016-07-01

Predation by grazing protists in aquatic habitats can influence prokaryotic community structure and provides a source of new, labile organic matter. Due to methodological difficulties associated with studies of deep-sea (below photic zone) microbiota, trophic interactions between eukaryotes and prokaryotes in mesopelagic and bathypelagic realms are largely obscured. Further complicating matters, examinations of trophic interactions using water samples that have been exposed to upwards of hundreds of atmospheres of pressure change prior to initiating experiments can potentially introduce significant artifacts. Here we present results of the first study of protistan grazing in water layers ranging from the euphotic zone to the bathypelagic, utilizing the Microbial Sampler-Submersible Incubation Device (MS-SID) that makes possible in situ studies of microbial activities. Protistan grazing in the mesopelagic and bathypelagic realm of the East Mediterranean Sea was quantified using fluorescently labeled prokaryotes (FLP) prepared from the naturally-occurring prokaryotic assemblages. These studies reveal daily prokaryotic removal due to grazing ranging from 31.3±5.9% at 40 m depth to 0.5±0.3% at 950 m. At 3540 m depth, where a chemocline habitat exists with abundant and active prokaryotes above Urania basin, the daily consumption of prokaryotes by protists was 19.9±6.6% of the in situ abundance.

Floodplains as a source of fine sediment in grazed landscapes: Tracing the source of suspended sediment in the headwaters of an intensively managed agricultural landscape

NASA Astrophysics Data System (ADS)

Yu, Mingjing; Rhoads, Bruce L.

2018-05-01

The flux of fine sediment within agricultural watersheds is an important factor determining the environmental quality of streams and rivers. Despite this importance, the contributions of sediment sources to suspended sediment loads within intensively managed agricultural watersheds remain poorly understood. This study assesses the provenance of fine suspended sediment in the headwater portion of a river flowing through an agricultural landscape in Illinois. Sediment source samples were collected from five sources: croplands, forested floodplains, grasslands, upper grazed floodplains, and lower grazed floodplains. Event-based and aggregated suspended sediment samples were collected from the stream at the watershed outlet. Quantitative geochemical fingerprinting techniques and a mixing model were employed to estimate the relative contributions of sediment from the five sources to the suspended sediment loads. To account for possible effects of small sample sizes, the analysis was repeated with only two sources: grazed floodplains and croplands/grasslands/forested floodplains. Results based on mean values of tracers indicate that the vast majority of suspended sediment within the stream (>95%) is derived from erosion of channel banks and the soil surface within areas of grazed floodplains. Uncertainty analysis based on Monte Carlo simulations indicates that mean values of tracer properties, which do not account for sampling variability in these properties, probably overestimate contributions from the two major sources. Nevertheless, this analysis still supports the conclusion that floodplain erosion accounts for the largest percentage of instream sediment (≈55-75%). Although grazing occurs over only a small portion of the total watershed area, grazed floodplains, which lie in close proximity to the stream channel, are an important source of sediment in this headwater steam system. Efforts to reduce fluxes of fine sediment in this intensively managed landscape should

Spatial distribution of nitrogen on grazed karst landscapes.

PubMed

Boyer, D G; Alloush, G A

2001-11-27

The impact on water quality by agricultural activity in karst terrain is an important consideration for resource management within the Appalachian region. Karst areas comprise about 18% of the region"s land area. An estimated one-third of the region"s farms, cattle, and agricultural market value are located on karst terrain. Mean nitrate concentrations in several karst springs in southeastern West Virginia exhibit a strong linear relationship with the percentage of agriculture land cover. Development of best management practices for efficient nitrogen (N) use and reduction of outflow of N to water from karst areas requires knowledge about N dynamics on those landscapes. Water extractable NO3-N and NH4-N were measured along transects at four soil depths in two grazed sinkholes and one wooded sinkhole. Distribution of soil NO3-N and NH4-N were related to frequency of animal presence and to topographic and hydrologic redistribution of soil and fecal matter in the grazed sinkholes. Karst pastures are characterized by under drainage and funneling of water and contaminants to the shallow aquifer. Control of NO3-N leaching from karst pasture may depend on management strategies that change livestock grazing behavior in sinkholes and reduce the opportunity for water and contaminants to quickly reach sinkhole drains.

Exotic-Dominated Grasslands Show Signs of Recovery with Cattle Grazing and Fire.

PubMed

Delaney, John T; Moranz, Raymond A; Debinski, Diane M; Engle, David M; Miller, James R

2016-01-01

In grasslands, overgrazing by domestic livestock, fertilization, and introduction of exotic forage species leads to plant communities consisting of a mixture of native and exotic species. These degraded grasslands present a problem for land managers, farmers, and restoration ecologists concerned with improving biodiversity while continuing to use the land for livestock production. Here we assessed the response of butterfly and plant community composition to the use of fire and moderate grazing by domestic cattle on degraded grasslands dominated by exotic plants. We evaluated change by comparing experimental pastures to two reference sites that were grasslands dominated by native plants. We used two burning and grazing treatments: 1) patch-burn graze, a heterogeneously managed treatment, where one third of the pasture is burned each year and cattle have free access to the entire pasture, and 2) graze-and-burn, a homogenously managed treatment, where the entire pasture is grazed each year and burned in its entirety every three years. We tested for change in the butterfly and plant community composition over seven years using Bray-Curtis dissimilarity measures. Over the course of seven years, degraded pastures in both treatments became more similar to reference sites with respect to the butterfly and plant communities. Only two butterfly species and two plant functional guilds exhibited significant linear trends over time, with varying responses. Compositional changes in both the butterfly and plant communities indicate that the use of moderate grazing and fire may shift butterfly and plant communities of exotic-dominated grasslands to be more similar to reference tallgrass prairies over time.

Spatial occupancy patterns and activity of arid rangeland cattle grazing small riparian pastures.

PubMed

Larson, Larry; Johnson, Douglas E; Wilson, Marie; Wilson, Kerry; Louhaichi, Mounir; Williams, John

2017-03-01

The spatial occupancy patterns and activity of cattle grazing three riparian pastures was investigated in northeastern Oregon using Global Positioning System (GPS) collars logging at 1-sec intervals. Cattle consistently selected plant communities as grazing areas that had forage in sufficient volume to meet their requirements and favored communities as resting areas that were dry and open. Cattle were stationary for more than 50% of the time in each pasture and consistently rested between dark and 04:00 hours. Interaction with stream channels was found to be 1-2% of total occupancy time and occurred on less than 10% of channel length. Cattle were indifferent or avoided channel areas relative to their area and, when in this zone, they spent most of their time moving not resting. Cattle did not prefer the stream bank zone and spent only 2% of their time in that zone. When occupied, the stream bank zone was used as a travel corridor to gain access to water or cross the channel to access other pasture areas. These results are in contrast with the general belief that cattle are a primary occupant of the stream bank/channel area; additional research is needed to define factors influencing cattle occupancy. © 2016 Japanese Society of Animal Science.

Transitions and coexistence along a grazing gradient in the Eurasian steppe

NASA Astrophysics Data System (ADS)

Ren, Haiyan; Taube, Friedelm; Zhang, Yingjun; Bai, Yongfei; Hu, Shuijin

2017-04-01

Ecological resilience theory has often been applied to explain species coexistence and range condition assessment of various community states and to explicate the dynamics of ecosystems. Grazing is a primary disturbance that can alter rangeland resilience by causing hard-to-reverse transitions in grasslands. Yet, how grazing affects the coexistence of plant functional group (PFG) and transition remains unclear. We conducted a six-year grazing experiment in a typical steppe of Inner Mongolia, using seven grazing intensities (0, 1.5, 3.0, 4.5, 6.0, 7.5 and 9.0 sheep/ hectare) and two grazing systems (i.e. a continuous annual grazing as in the traditional grazing system, and a mixed grazing system combining grazing and haymaking), to examine grazing effects on plant functional group shifts and species coexistence in the semi-arid grassland system. Our results indicate that the relative richness of dominant bunchgrasses and forbs had a compensatory coexistence at all grazing intensities, and the richness of rhizomatous grasses fluctuated but was persistent. The relative productivity of dominant bunchgrasses and rhizomatous grasses had compensatory interactions with grazing intensity and grazing system. Dominant bunchgrasses and rhizomatous grasses resist grazing effects by using their dominant species functional traits: high specific leaf area and low leaf nitrogen content. Our results suggest that: 1. Stabilizing mechanisms beyond grazing management are more important in determining plant functional group coexistence and ecological resilience. 2. Plant functional group composition is more important in influencing ecosystem functioning than diversity. 3. Ecosystem resilience at a given level is related to the biomass of dominant PFG, which is determined by a balanced shift between dominant species biomass. The relatively even ecosystem resilience along the grazing gradient is attributed to the compensatory interactions of dominant species in their biomass variations

Streambank response to simulated grazing

Treesearch

Warren P. Clary; John W. Kinney

2000-01-01

Simulated grazing techniques were used to investigate livestock impacts on structural characteristics of streambanks. The treatments consisted of no grazing, moderate early summer grazing, moderate mid summer grazing, and heavy season-long grazing. The heavy season-long treatment resulted in a 11.5 cm depression of the streambank surface, while the moderate treatments...

Semiarid rangeland is resilient to summer fire and post-fire grazing utilization

USDA-ARS?s Scientific Manuscript database

1. Most wildfires occur during summer in the northern hemisphere, the area burned annually is increasing, and fire effects during this season are least understood. Livestock grazing is a primary use of rangelands affected by wildfire, but post-fire grazing management is not well-supported with dat...

Evidence targeted grazing benefits to invaded rangelands can increase over extended time frames

USDA-ARS?s Scientific Manuscript database

Prescribed grazing uses livestock to address rangeland management issues such as woody plant encroachment, accumulations of flammable biomass and exotic weed invasions. Invasive weed responses to prescribed grazing have proven variable. For instance, a given livestock species can sharply reduce ab...

Effects of grazing intensity and chemical seedhead suppression on steers grazing tall fescue pastures

USDA-ARS?s Scientific Manuscript database

The first year of a 2 yr grazing study was conducted to evaluate use of Chaparral™ to suppress reproductive growth in tall fescue grazed with low and moderate grazing intensities. Chaparral applications (0 and 2.0 oz/acre) and grazing intensities were arranged as RCBD with three replications. Variab...

43 CFR 9239.3 - Grazing, Alaska.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., DEPARTMENT OF THE INTERIOR TECHNICAL SERVICES (9000) TRESPASS Kinds of Trespass § 9239.3 Grazing, Alaska. (a... other authorization from the Bureau of Land Management, is prohibited and constitutes trespass... in the notice will be deemed to have been willful. (3) Where the owner of the trespassing livestock...

43 CFR 9239.3 - Grazing, Alaska.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., DEPARTMENT OF THE INTERIOR TECHNICAL SERVICES (9000) TRESPASS Kinds of Trespass § 9239.3 Grazing, Alaska. (a... other authorization from the Bureau of Land Management, is prohibited and constitutes trespass... in the notice will be deemed to have been willful. (3) Where the owner of the trespassing livestock...

43 CFR 9239.3 - Grazing, Alaska.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., DEPARTMENT OF THE INTERIOR TECHNICAL SERVICES (9000) TRESPASS Kinds of Trespass § 9239.3 Grazing, Alaska. (a... other authorization from the Bureau of Land Management, is prohibited and constitutes trespass... in the notice will be deemed to have been willful. (3) Where the owner of the trespassing livestock...

43 CFR 9239.3 - Grazing, Alaska.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., DEPARTMENT OF THE INTERIOR TECHNICAL SERVICES (9000) TRESPASS Kinds of Trespass § 9239.3 Grazing, Alaska. (a... other authorization from the Bureau of Land Management, is prohibited and constitutes trespass... in the notice will be deemed to have been willful. (3) Where the owner of the trespassing livestock...

Nest survival of American Coots relative to grazing, burning, and water depths

USGS Publications Warehouse

Austin, Jane E.; Buhl, Deborah A.

2011-01-01

Water and emergent vegetation are key features influencing nest site selection and success for many marsh-nesting waterbirds. Wetland management practices such as grazing, burning, and water-level manipulations directly affect these features and can influence nest survival. We used model selection and before-after-control-impact approaches to evaluate the effects of water depth and four common land-management practices or treatments, i.e., summer grazing, fall grazing, fall burning, and idle (no active treatment) on nest survival of American coots (Fulica americana) nesting at Grays Lake, a large montane wetland in southeast Idaho. The best model included the variables year × treatment, and quadratic functions of date, water depth, and nest age; height of vegetation at the nest did not improve the best model. However, results from the before-after-control-impact analysis indicate that management practices affected nest success via vegetation and involved interactions of hydrology, residual vegetation, and habitat composition. Nest success in idled fields changed little between pre- and post-treatment periods, whereas nest success declined in fields that were grazed or burned, with the most dramatic declines the year following treatments. The importance of water depth may be amplified in this wetland system because of rapid water-level withdrawal during the nesting season. Water and land-use values for area ranchers, management for nesting waterbirds, and long-term wetland function are important considerations in management of water levels and vegetation.

32 CFR 644.318 - Compliance with State Coastal Zone Management Programs.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 32 National Defense 4 2010-07-01 2010-07-01 true Compliance with State Coastal Zone Management... (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal § 644.318 Compliance with State Coastal Zone Management Programs. Subpart H will outline the provisions of the Coastal Zone Management Act of 1972, as...

32 CFR 644.318 - Compliance with State Coastal Zone Management Programs.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 32 National Defense 4 2011-07-01 2011-07-01 false Compliance with State Coastal Zone Management... (CONTINUED) REAL PROPERTY REAL ESTATE HANDBOOK Disposal § 644.318 Compliance with State Coastal Zone Management Programs. Subpart H will outline the provisions of the Coastal Zone Management Act of 1972, as...

Livestock grazing supports native plants and songbirds in a California annual grassland.

PubMed

Gennet, Sasha; Spotswood, Erica; Hammond, Michele; Bartolome, James W

2017-01-01

Over eight years we measured the effects of plant community composition, vegetation structure, and livestock grazing on occurrence of three grassland bird species-Western Meadowlark (Sturnella neglecta), Horned Lark (Eremophila alpestris), and Grasshopper Sparrow (Ammodramus savannarum)-at sites in central California during breeding season. In California's Mediterranean-type climatic region, coastal and inland grassland vegetation is dominated by exotic annual grasses with occasional patches of native bunchgrass and forbs. Livestock grazing, primarily with beef cattle, is the most widely used management tool. Compared with ungrazed plots, grazed plots had higher bare ground, native plant cover, and vertically heterogeneous vegetation. Grazed plots also had less plant litter and shorter vegetation. Higher native plant cover, which is predominantly composed of bunchgrasses in our study area, was associated with livestock grazing and north-facing aspects. Using an information theoretic approach, we found that all three bird species had positive associations with native plant abundance and neutral (Western Meadowlark, Grasshopper Sparrow) or positive (Horned Lark) association with livestock grazing. All species favored flatter areas. Horned Larks and Western Meadowlark occurred more often where there were patches of bare ground. Western Meadowlarks and Grasshopper Sparrows were most common on north-facing slopes, suggesting that these species may be at risk from projected climate change. These findings demonstrate that livestock grazing is compatible with or supports grassland bird conservation in Mediterranean-type grasslands, including areas with high levels of exotic annual grass invasion, in part because grazing supports the persistence of native plants and heterogeneity in vegetation structure. However, conservation of low-lying grasslands with high native species presence, and active management to increase the abundance of native plant species are also likely to

Range-wide assessment of livestock grazing across the sagebrush biome

USGS Publications Warehouse

Veblen, Kari E.; Pyke, David A.; Jones, Christopher A.; Casazza, Michael L.; Assal, Timothy J.; Farinha, Melissa A.

2011-01-01

Domestic livestock grazing occurs in virtually all sagebrush habitats and is a prominent disturbance factor. By affecting habitat condition and trend, grazing influences the resources required by, and thus, the distribution and abundance of sagebrush-obligate wildlife species (for example, sage-grouse Centrocercus spp.). Yet, the risks that livestock grazing may pose to these species and their habitats are not always clear. Although livestock grazing intensity and associated habitat condition may be known in many places at the local level, we have not yet been able to answer questions about use, condition, and trend at the landscape scale or at the range-wide scale for wildlife species. A great deal of information about grazing use, management regimes, and ecological condition exists at the local level (for individual livestock management units) under the oversight of organizations such as the Bureau of Land Management (BLM). However, the extent, quality, and types of existing data are unknown, which hinders the compilation, mapping, or analysis of these data. Once compiled, these data may be helpful for drawing conclusions about rangeland status, and we may be able to identify relationships between those data and wildlife habitat at the landscape scale. The overall objective of our study was to perform a range-wide assessment of livestock grazing effects (and the relevant supporting data) in sagebrush ecosystems managed by the BLM. Our assessments and analyses focused primarily on local-level management and data collected at the scale of BLM grazing allotments (that is, individual livestock management units). Specific objectives included the following: 1. Identify and refine existing range-wide datasets to be used for analyses of livestock grazing effects on sagebrush ecosystems. 2. Assess the extent, quality, and types of livestock grazing-related natural resource data collected by BLM range-wide (i.e., across allotments, districts and regions). 3. Compile and

Effects of seasonal changes in feeding management under part-time grazing on the evolution of the composition and coagulation properties of raw milk from ewes.

PubMed

Abilleira, E; Virto, M; Nájera, A I; Salmerón, J; Albisu, M; Pérez-Elortondo, F J; Ruiz de Gordoa, J C; de Renobales, M; Barron, L J R

2010-09-01

Ewe raw milk composition, rennet coagulation parameters, and curd texture were monitored throughout the milk production season in 11 commercial flocks reared under a part-time grazing system. Milking season lasted from February to July. During that period, the diet of the animals shifted from indoor feeding, consisting of concentrate and forage, to an outdoor grazing diet. Lean dry matter, fat, protein, calcium, and magnesium contents increased throughout the milking season, as did rennet coagulation time, curd firmness, and curd resistance to compression. However, lean dry matter, protein content, and curd resistance to compression stabilized when sheep started to graze. Principal component analysis correlated curd resistance to compression and proteins, whereas curd firmness was highly correlated with fat content and minerals. Discriminant analysis distributed milk samples according to the feeding management. Curd firmness, fat, and magnesium turned out to be discriminant variables. Those variables reflected the evolution of the composition and coagulation parameters when fresh pasture prevailed over other feeds in the diet of the flocks. The present study shows that seasonal changes associated with feeding management influence milk technological quality and that milk of good processing quality can be obtained under part-time grazing. Copyright (c) 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A degree-day model of sheep grazing influence on alfalfa weevil and crop characteristics.

PubMed

Goosey, Hayes B

2012-02-01

Domestic sheep (Ovis spp.) grazing is emerging as an integrated pest management tactic for alfalfa weevil, Hypera postica (Gyllenhal), management and a degree-day model is needed as a decision and support tool. In response to this need, grazing exclosures with unique degree-days and stocking rates were established at weekly intervals in a central Montana alfalfa field during 2008 and 2009. Analyses indicate that increased stocking rates and grazing degree-days were associated with decreased crop levels of weevil larvae. Larval data collected from grazing treatments were regressed against on-site and near-site temperatures that produced the same accuracy. The near-site model was chosen to encourage producer acceptance. The regression slope differed from zero, had an r2 of 0.83, and a root mean square error of 0.2. Crop data were collected to achieve optimal weevil management with forage quality and yield. Differences were recorded in crude protein, acid and neutral detergent fibers, total digestible nutrients, and mean stage by weight. Stem heights differed with higher stocking rates and degree-days recording the shortest alfalfa canopy height at harvest. The degree-day model was validated at four sites during 2010 with a mean square prediction error of 0.74. The recommendation from this research is to stock alfalfa fields in the spring before 63 DD with rates between 251 and 583 sheep days per hectare (d/ha). Sheep should be allowed to graze to a minimum of 106 and maximum of 150 DD before removal. This model gives field entomologists a new method for implementing grazing in an integrated pest management program.

Cattle grazing and fish recovery on US federal lands: can social-ecological systems science help?

Treesearch

Susan Charnley; Hannah Gosnell; Kendra L Wendel; Mary M Rowland; Michael J Wisdom

2018-01-01

In the western US, grazing management on federal lands containing habitat for fish species listed under the US Endangered Species Act (ESA) has sparked social conflict and litigation for decades. To date, the problem has been addressed through a top-down environmental governance system, but rangeland managers and grazing permittees now believe there is a need for more...

Effects of cattle grazing and haying on wildlife conservation at National Wildlife Refuges in the United States

NASA Astrophysics Data System (ADS)

Strassmann, Beverly I.

1987-01-01

The National Wildlife Refuge System is perhaps the most important system of federal lands for protecting wildlife in the United States. Only at refuges has wildlife conservation been legislated to have higher priority than either recreational or commercial activities. Presently, private ranchers and farmers graze cattle on 981,954 ha and harvest hay on 12,021 ha at 123 National Wildlife Refuges. US Fish and Wildlife Service policy is to permit these uses primarily when needed to benefit refuge wildlife. To evaluate the success of this policy, I surveyed grassland management practices at the 123 refuges. The survey results indicate that in fiscal year 1980 there were 374,849 animal unit months (AUMs) of cattle grazing, or 41% more than was reported by the Fish and Wildlife Service. According to managers' opinions, 86 species of wildlife are positively affected and 82 are negatively affected by refuge cattle grazing or haying. However, quantitative field studies of the effect of cattle grazing and haying on wildlife coupled with the survey data on how refuge programs are implemented suggest that these activities are impeding the goal of wildlife conservation. Particular management problems uncovered by the survey include overgrazing of riparian habitats, wildlife mortality due to collisions with cattle fences, and mowing of migratory bird habitat during the breeding season. Managers reported that they spend 919,740 administering cattle grazing and haying; thus refuge grazing and haying programs are also expensive. At any single refuge these uses occupy up to 50% of refuge funds and 55% of staff time. In light of these results, prescribed burning may be a better wildlife management option than is either cattle grazing or haying.

Spatial and temporal variability of N2O emission on grazed pastures - influence of management and meteorological drivers

NASA Astrophysics Data System (ADS)

Ammann, Christof; Voglmeier, Karl; Jocher, Markus

2017-04-01

Grazed pastures are considered as strong sources of the greenhouse gas nitrous oxide (N2O) with local hot-spots resulting from the uneven spatial distribution of the excretion of the grazing animals. Especially urine patches can result in a high local nitrogen (N) surplus, which can cause large deviations from average soil conditions. The strong spatial and temporal variability of the gaseous emissions represents an inherent problem for the quantification, interpretation and modelling. Micrometeorological methods integrating over a larger domain like the eddy covariance method are well suited to quantify the integrated ecosystem emissions of N2O. In contrast, chamber methods are more useful to investigate specific underlying processes and their dependences on driving parameters. We present results of a pasture experiment in western Switzerland where eddy covariance and chamber measurements of N2O fluxes have been performed using a very sensitive and fast response quantum cascade laser (QCL) instrument. Small scale emissions of N2O from dung and urine patches as well as from other "background" pasture surface areas were quantified using an optimized 'fast-box' chamber system. Variable and partly high N2O emissions of the pasture were observed during all seasons. Beside management factors (grazing phases, fertiliser application), temperature and soil moisture showed a large effect on the fluxes. Fresh urine patches from grazing cows were found to be main emission sources and their temporal dynamics was studied in detail. We present a first approach to up-scale the chamber measurements to the field-scale and compare the results with the eddy covariance measurements.

Assessing the production and economic benefits from preventing cows grazing on wet soils in New Zealand.

PubMed

Laurenson, Seth; Houlbrooke, David J; Beukes, Pierre C

2016-10-01

Intensive grazing by cattle on wet pasture can have a negative effect on soil physical quality and future pasture production. On a North Otago dairy farm in New Zealand, experimental plots were monitored for four years to assess whether preventing cow grazing of wet pastures during the milking season would improve soil structure and pasture production compared with unrestricted access to pastures. The DairyNZ Whole Farm Model was used to scale up results to a farm system level and ascertain the cost benefit of deferred grazing management. Soils under deferred grazing management had significantly higher total porosity, yet no significant improvement in macroporosity (values ranging between 0.112 and 0.146 m(3)  m(-3) ). Annual pasture production did not differ between the control and deferred grazing treatments, averaging 17.0 ± 3.8 and 17.9 ± 4.1 t DM ha(-1) year(-1) respectively (P > 0.05). Furthermore, whole farm modelling indicated that farm operating profit was reduced by NZ$1683 ha(-1) year(-1) (four-year average) under deferred grazing management. Deferring dairy cow grazing from wet Pallic soils in North Otago was effective in improving soil structure (measured as total soil porosity), yet did not lead to a significant increase in pasture production. Whole farm modelling indicated no economic benefit of removing cows from wet soils during the milking season. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Methods for monitoring the effects of grazing management on bank erosion and channel morphology, Fever River, Pioneer Farm, Wisconsin, 2004

USGS Publications Warehouse

Peppler, Marie C.; Fitzpatrick, Faith A.

2005-01-01

Bank erosion is a natural process that occurs in meandering streams (Leopold and others, 1964); however, in the Midwestern United States, historical and present agricultural activities in uplands, riparian areas, and channels have increased erosion (Waters, 1995; Lyons and others, 2000; Simon and Rinaldi, 2000; and Knox, 2001). Reducing streambank erosion is important because sediment carried by streams has adverse environmental effects; for example, sediment carried by streams is a major source of phosphorus (Waters, 1995). Continuous cattle grazing in riparian areas may increase local erosion processes in a meandering stream by removal or trampling of bank vegetation, which in turn affects channel morphology, water chemistry, and fish and aquatic-insect habitat (Kauffman and Krueger, 1984; Fitch and Adams, 1998). However, studies of livestock exclusion from riparian corridors have shown mixed results in reducing bank erosion (Trimble, 1994; Sarr, 2002). Some studies have shown reduced bank erosion after row-cropped or continuously grazed riparian areas are converted to managed grazing (see inset box) (Lyons and others, 2000; Sovell and others, 2000; and Zaimes and others, 2004).

Phosphorus fertilizer and grazing management effects on phosphorus in runoff from dairy pastures.

PubMed

Dougherty, Warwick J; Nicholls, Paul J; Milham, Paul J; Havilah, Euie J; Lawrie, Roy A

2008-01-01

Fertilizer phosphorus (P) and grazing-related factors can influence runoff P concentrations from grazed pastures. To investigate these effects, we monitored the concentrations of P in surface runoff from grazed dairy pasture plots (50 x 25 m) treated with four fertilizer P rates (0, 20, 40, and 80 kg ha(-1) yr(-1)) for 3.5 yr at Camden, New South Wales. Total P concentrations in runoff were high (0.86-11.13 mg L(-1)) even from the control plot (average 1.94 mg L(-1)). Phosphorus fertilizer significantly (P < 0.001) increased runoff P concentrations (average runoff P concentrations from the P(20), P(40), and P(80) treatments were 2.78, 3.32, and 5.57 mg L(-1), respectively). However, the magnitude of the effect of P fertilizer varied between runoff events (P < 0.01). Further analysis revealed the combined effects on runoff P concentration of P rate, P rate x number of applications (P < 0.001), P rate x time since fertilizer (P < 0.001), dung P (P < 0.001), time since grazing (P < 0.05), and pasture biomass (P < 0.001). A conceptual model of the sources of P in runoff comprising three components is proposed to explain the mobilization of P in runoff and to identify strategies to reduce runoff P concentrations. Our data suggest that the principal strategy for minimizing runoff P concentrations from grazed dairy pastures should be the maintenance of soil P at or near the agronomic optimum by the use of appropriate rates of P fertilizer.

Impacts of cattle grazing on spatio-temporal variability of soil moisture and above-ground live plant biomass in mixed grasslands

NASA Astrophysics Data System (ADS)

Virk, Ravinder

Areas with relatively high spatial heterogeneity generally have more biodiversity than spatially homogeneous areas due to increased potential habitat. Management practices such as controlled grazing also affect the biodiversity in grasslands, but the nature of this impact is not well understood. Therefore this thesis studies the impacts of variation in grazing on soil moisture and biomass heterogeneity. These are not only important in terms of management of protected grasslands, but also for designing an effective grazing system from a livestock management point of view. This research is a part of the cattle grazing experiment underway in Grasslands National Park (GNP) of Canada since 2006, as part of the adaptive management process for restoring ecological integrity of the northern mixed-grass prairie region. An experimental approach using field measurements and remote sensing (Landsat) was combined with modelling (CENTURY) to examine and predict the impacts of grazing intensity on the spatial heterogeneity and patterns of above-ground live plant biomass (ALB) in experimental pastures in a mixed grassland ecosystem. The field-based research quantified the temporal patterns and spatial variability in both soil moisture (SM) and ALB, and the influence of local intra-seasonal weather variability and slope location on the spatio-temporal variability of SM and ALB at field plot scales. Significant impacts of intra-seasonal weather variability, slope position and grazing pressure on SM and ALB across a range of scales (plot and local (within pasture)) were found. Grazing intensity significantly affected the ALB even after controlling for the effect of slope position. Satellite-based analysis extended the scale of interest to full pastures and the surrounding region to assess the effects of grazing intensity on the spatio-temporal pattern of ALB in mixed grasslands. Overall, low to moderate grazing intensity showed increase in ALB heterogeneity whereas no change in ALB

Sheep grazing in the North Atlantic region: A long-term perspective on environmental sustainability.

PubMed

Ross, Louise C; Austrheim, Gunnar; Asheim, Leif-Jarle; Bjarnason, Gunnar; Feilberg, Jon; Fosaa, Anna Maria; Hester, Alison J; Holand, Øystein; Jónsdóttir, Ingibjörg S; Mortensen, Lis E; Mysterud, Atle; Olsen, Erla; Skonhoft, Anders; Speed, James D M; Steinheim, Geir; Thompson, Des B A; Thórhallsdóttir, Anna Gudrún

2016-09-01

Sheep grazing is an important part of agriculture in the North Atlantic region, defined here as the Faroe Islands, Greenland, Iceland, Norway and Scotland. This process has played a key role in shaping the landscape and biodiversity of the region, sometimes with major environmental consequences, and has also been instrumental in the development of its rural economy and culture. In this review, we present results of the first interdisciplinary study taking a long-term perspective on sheep management, resource economy and the ecological impacts of sheep grazing, showing that sustainability boundaries are most likely to be exceeded in fragile environments where financial support is linked to the number of sheep produced. The sustainability of sheep grazing can be enhanced by a management regime that promotes grazing densities appropriate to the site and supported by area-based subsidy systems, thus minimizing environmental degradation, encouraging biodiversity and preserving the integrity of ecosystem processes.

43 CFR 4120.3-9 - Water rights for the purpose of livestock grazing on public lands.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Water rights for the purpose of livestock grazing on public lands. 4120.3-9 Section 4120.3-9 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) GRAZING ADMINISTRATION-EXCLUSIVE OF ALASKA...

Cow weights and calf production for pasture 12-C Lehmann lovegrass grazing trials, 1982 to 1993

Treesearch

Phil R. Ogden; E. Lamar Smith

2003-01-01

The purpose of the grazing trials described in this paper was to provide information to aid in the development of grazing management strategies where Lehmann lovegrass has become a dominant species. Seven pastures were utilized from 1984 to 1987 for a comparison of four yearlong stocking rates to seasonal grazing rotated through three pastures. A second trial, 1988 to...

Effects of Introduced Grasses, Grazing and Fire on Regional Biogeochemistry in Hawaii

NASA Astrophysics Data System (ADS)

Elmore, A. J.; Asner, G. P.

2003-12-01

African grasses introduced for grazing have expanded in geographic extent in mesic tropical systems of Hawaii and other regions of the world. Grassland expansion leads to increases in fire frequency, speeding woodland and forest destruction at greater geographic scales than occurs with grazing alone. At Pu'uwa'awa'a Ranch, Hawaii, restoration of the native woodland habitat has become a critical objective following the introduction and dominance of the African grass species Pennisetum clandestinum and P. setaceum. Grazing and grass-fueled fires have destroyed over 60% of the original forest. To stabilize these communities, managers must balance the combined effects of grazing and fire. Grazing reduces the recruitment success of native tropical trees, but grazing also reduces fire risk by moderating grass fuel conditions and restricting the extent and density of the most flammable grass species. Our study focuses on two questions: (1) What grazing intensity is necessary to change the fire conditions of a region given in situ soil and precipitation conditions? (2) Have long-term grazing conditions altered soil carbon and nitrogen stocks? We used high resolution imaging spectrometer data to measure photosynthetic and non-photosynthetic vegetation cover, analysis of soil carbon and nitrogen stocks, and measurements of plant community composition along gradients in grazing intensity. P. setaceum, the more flammable alien grass, was dominant where grazing intensity was low and at lower elevations where precipitation is low. The less flammable grass, P. clandestinum, occurred in regions of high grazing intensity and higher precipitation. Grazing influenced the dominance of P. setaceum and P. clandestinum only where precipitation and soil characteristics were suitable for both grasses to occur. At suitable sites, grazing reduced fire conditions through a species sift towards P. clandestinum. Soil carbon and nitrogen stocks decreased with grazing intensity, which was

Traditional cattle grazing in a mosaic alkali landscape: effects on grassland biodiversity along a moisture gradient.

PubMed

Török, Péter; Valkó, Orsolya; Deák, Balázs; Kelemen, András; Tóthmérész, Béla

2014-01-01

Extensively managed pastures are of crucial importance in sustaining biodiversity both in local- and landscape-level. Thus, re-introduction of traditional grazing management is a crucial issue in grassland conservation actions worldwide. Traditional grazing with robust cattle breeds in low stocking rates is considered to be especially useful to mimic natural grazing regimes, but well documented case-studies are surprisingly rare on this topic. Our goal was to evaluate the effectiveness of traditional Hungarian Grey cattle grazing as a conservation action in a mosaic alkali landscape. We asked the following questions: (i) How does cattle grazing affect species composition and diversity of the grasslands? (ii) What are the effects of grazing on short-lived and perennial noxious species? (iii) Are there distinct effects of grazing in dry-, mesophilous- and wet grassland types? Vegetation of fenced and grazed plots in a 200-ha sized habitat complex (secondary dry grasslands and pristine mesophilous- and wet alkali grasslands) was sampled from 2006-2009 in East-Hungary. We found higher diversity scores in grazed plots compared to fenced ones in mesophilous- and wet grasslands. Higher cover of noxious species was typical in fenced plots compared to their grazed counterparts in the last year in every studied grassland type. We found an increasing effect of grazing from the dry- towards the wet grassland types. The year-to-year differences also followed similar pattern: the site-dependent effects were the lowest in the dry grassland and an increasing effect was detected along the moisture gradient. We found that extensive Hungarian Grey cattle grazing is an effective tool to suppress noxious species and to create a mosaic vegetation structure, which enables to maintain high species richness in the landscape. Hungarian Grey cattle can feed in open habitats along long moisture gradient, thus in highly mosaic landscapes this breed can be the most suitable livestock type.

Effects of grazing and burning on densities and habitats of breeding ducks in North Dakota

USGS Publications Warehouse

Kruse, Arnold D.; Bowen, Bonnie S.

1996-01-01

Native grassland communities controlled by public agencies become increasingly important to the maintenance of many wildlife species as privately owned grasslands are destroyed or degraded for farming, mining, and development. In turn, wildlife on publicly owned grasslands are affected by the management techniques practiced by local managers. We studied the effects of grazing and prescribed burning on upland-nesting ducks and the structure and type of vegetation from 1980 to 1988 at the Lostwood National Wildlife Refuge (NWR) in northwestern North Dakota. Mallard (Anas platyrhynchos), the most abundant species at Lostwood NWR, had lower (P < 0.05) annual nest densities on experimental and control fields in the later years than in the early years of the study. Spring burning reduced (P = 0.016) nest densities of gadwall (A. strepera). Spring grazing reduced nest densities of gadwall (P = 0.014), and blue-winged teal (A. discors, P = 0.023). Nest density of gadwall increased (P = 0.018) after spring grazing was terminated. On the summer burn/spring graze fields, blue-winged teal had lower (P = 0.010) nest densities after treatments (1987-88) than before treatments (1980-81). Nest success was high (mallard 34%, gadwall 45%, blue-winged teal 31%) but was not influenced (P 0.16) by the burning and grazing treatments. During the study, the amount of grass/brush increased, whereas the amount of brush and brush/grass decreased on control and treatment fields. During the years with burning and grazing, short vegetation increased and tall vegetation decreased. On the spring graze fields, 1 year after grazing ended the vegetation was similar to that on the control fields. The spring burn and summer burn/spring graze fields recovered more slowly. Brushy species such as western snowberry (Symphoricarpos occidentalis) provided attractive nesting habitat for many upland-nesting waterfowl species, especially mallard, gadwall, American wigeon (A. americana), and northern pintail (A

Effects of past and present livestock grazing on herpetofauna in a landscape-scale experiment.

PubMed

Kay, Geoffrey M; Mortelliti, Alessio; Tulloch, Ayesha; Barton, Philip; Florance, Daniel; Cunningham, Saul A; Lindenmayer, David B

2017-04-01

Livestock grazing is the most widespread land use on Earth and can have negative effects on biodiversity. Yet, many of the mechanisms by which grazing leads to changes in biodiversity remain unresolved. One reason is that conventional grazing studies often target broad treatments rather than specific parameters of grazing (e.g., intensity, duration, and frequency) or fail to account for historical grazing effects. We conducted a landscape-scale replicated grazing experiment (15,000 km 2 , 97 sites) to examine the impact of past grazing management and current grazing regimes (intensity, duration, and frequency) on a community of ground-dwelling herpetofauna (39 species). We analyzed community variables (species richness and composition) for all species and built multiseason patch-occupancy models to predict local colonization and extinction for the 7 most abundant species. Past grazing practices did not influence community richness but did affect community composition and patch colonization and extinction for 4 of 7 species. Present grazing parameters did not influence community richness or composition, but 6 of the 7 target species were affected by at least one grazing parameter. Grazing frequency had the most consistent influence, positively affecting 3 of 7 species (increased colonization or decreased extinction). Past grazing practice affected community composition and population dynamics in some species in different ways, which suggests that conservation planners should examine the different grazing histories of an area. Species responded differently to specific current grazing practices; thus, incentive programs that apply a diversity of approaches rather than focusing on a change such as reduced grazing intensity should be considered. Based on our findings, we suggest that determining fine-scale grazing attributes is essential for advancing grazing as a conservation strategy. © 2016 Society for Conservation Biology.

Explorative study on management model of tourism business zone at Kuta, Bali

NASA Astrophysics Data System (ADS)

Astawa, I. K.; Suardani, A. A. P.; Harmini, A. A. A. N.

2018-01-01

Business activities through asset management of indigenous village of Kuta provide an opportunity for the community to participate in improving their welfare. This study aims to analyze the management model of Kuta’s tourism business zone, the involvement of stakeholders in the management of Kuta’s tourism business zone in indigenous village of Kuta and the implications of each business tourism zone in indigenous village of Kuta in the level of community welfare in each zone. Data collection was done by observation, interview, questionnaire, and documentation. The main instrument of this study is the researchers themselves assisted with interview guideline. The results showed that the management model has been arranged in 5 tourism business zones in indigenous village of Kuta. The involvement of all stakeholders in the management of the tourism business zone follows the procedure of execution of duties and provides security, comfort and certainty of doing business activities at each zone. The implications of the tourism business in the level of community welfare in each zone in indigenous village of Kuta have been able to bring happiness in business and all community are satisfied with the income they earned from work in each business zone.

Influence of grazing management on the seasonal change in testicular morphology in Corriedale rams.

PubMed

Bielli, A; Pedrana, G; Gastel, M T; Castrillejo, A; Moraña, A; Lundeheim, N; Forsberg, M; Rodriguez-Martinez, H

1999-06-28

The present study was conducted: (a) to determine the degree of seasonal variation in testis stereology in Corriedale rams between autumn and winter; (b) to test the hypothesis that testis stereology of Corriedale rams grazing native pastures during autumn and winter would differ from those of Corriedale rams grazing sown pastures and supplemented with grain during the same period; and (c) to determine whether Sertoli cell numbers differ in adult rams between the breeding season (autumn) and the following non-breeding season (winter). Twenty experimental animals were studied. Six rams (autumn control group, C-A) that had been grazing on native pasture (stocking rate = 2-3 animals ha(-1)) were castrated at the beginning of the experiment (March, early autumn). Seven rams (winter control group, C-W) continued to graze on native pasture at the same stocking rate until the end of the experiment (August, late winter). Another seven rams (treated group, T) grazed on improved pasture (stocking rate = 1-2 animals ha(-1)) and were supplemented with 1 kg grain ram(-1) day(-1) until the end of the experiment. Live weight, scrotal circumference, serum testosterone concentration and selected testicular stereological parameters were measured. The treatment did not impede the winter reduction in testicular activity and reduced its magnitude slightly (group T) compared with controls (group C-W). Sertoli cell numbers were higher in autumn (group C-A) than in winter, both on native (group C-W) and sown pastures (group T). Diminishing Sertoli cell numbers between autumn and the following winter suggest the occurrence of that Sertoli cell death during this period. The results indicate that, although the reproductive activity of Corriedale rams is moderately seasonal, a restricted change in grazing and grain supplementation can only modify it to a limited extent.

Using Different Grazing Practices for Increasing Plant Biodiversity in the Dykes and Embankments Along the Rhône River (Southern France)

NASA Astrophysics Data System (ADS)

Moinardeau, Cannelle; Mesléard, François; Dutoit, Thierry

2016-12-01

Extensive grazing by domestic herbivores is a widespread management practice used since the 80s in many European agro-ecosystems such as semi-natural grasslands to maintain open habitats and to enhance biodiversity. Such grazing systems have principally been tested in cultural ecosystems of high nature value threatened by grazing abandonment. However, there have been few case studies of grazing management in very anthropized ecosystems, such as the new ecosystems created by urban or industrial conversions. In Southern France, the Rhône channeling for navigation and electricity production generated in the 1950s the construction of thousands of hectares of dams and dykes which were colonized naturally by diverse plant communities. Yet shrub encroachment and the consequent recourse to mechanical cutting to facilitate control and maintenance, raise the question of how best to maintain and manage these new habitats. Consequently, since 1999, different low-intensity grazing management systems using rustic breeds of cattle, horses and goats have been tested on a protected reserve of 1454 ha located in the lower part of the Rhône river. Extensive grazing, more than cutting or no management, positively modified vegetation heterogeneity (beta-diversity), the target open grassland species, but not plant species richness (alpha-diversity). However, the current monitoring shows that these benefits of grazing will be confirmed only if low-intensity grazing systems are sustained and if new adaptations can be also made, such as the use of mixed stocking and the establishment of multiyear contracts with breeders.

Using Different Grazing Practices for Increasing Plant Biodiversity in the Dykes and Embankments Along the Rhône River (Southern France).

PubMed

Moinardeau, Cannelle; Mesléard, François; Dutoit, Thierry

2016-12-01

Extensive grazing by domestic herbivores is a widespread management practice used since the 80s in many European agro-ecosystems such as semi-natural grasslands to maintain open habitats and to enhance biodiversity. Such grazing systems have principally been tested in cultural ecosystems of high nature value threatened by grazing abandonment. However, there have been few case studies of grazing management in very anthropized ecosystems, such as the new ecosystems created by urban or industrial conversions. In Southern France, the Rhône channeling for navigation and electricity production generated in the 1950s the construction of thousands of hectares of dams and dykes which were colonized naturally by diverse plant communities. Yet shrub encroachment and the consequent recourse to mechanical cutting to facilitate control and maintenance, raise the question of how best to maintain and manage these new habitats. Consequently, since 1999, different low-intensity grazing management systems using rustic breeds of cattle, horses and goats have been tested on a protected reserve of 1454 ha located in the lower part of the Rhône river. Extensive grazing, more than cutting or no management, positively modified vegetation heterogeneity (beta-diversity), the target open grassland species, but not plant species richness (alpha-diversity). However, the current monitoring shows that these benefits of grazing will be confirmed only if low-intensity grazing systems are sustained and if new adaptations can be also made, such as the use of mixed stocking and the establishment of multiyear contracts with breeders.

The effects of grazing intensity on soil processes in a Mediterranean protected area.

PubMed

Panayiotou, Evaggelia; Dimou, Maria; Monokrousos, Nikolaos

2017-08-08

We investigated the temporal and among-site differentiation of soil functionality properties in fields under different grazing intensities (heavy and light) and compared them to those found in their adjacent hedgerows, consisting either of wooden shrubs (Rubus canescens) or of high trees (Populus sp.), during the cold and humid seasons of the year. We hypothesized that greater intensity of grazing would result in higher degradation of the soil system. The grazing factor had a significant effect on soil organic C and N, microbial biomass C, microbial biomass N, microbial activity, and β-glucosidase, while acid phosphatase and urease activity were not found to differ significantly among the management systems. The intensity of grazing affected mostly the chemical properties of soil (organic C and N) and altered significantly the composition of the soil microbial community, as lower C:N ratio of the microbial biomass indicates the dominance of bacteria over fungi in the heavily grazed fields. All estimated biological variables presented higher values in the humid period, although the pattern of differentiation was similar at both sampling times, revealing that site-specific variations were more pronounced than the time-specific ones. Our results indicate that not all C, N, and P dynamics were equally affected by grazing. Management plans applied to pastures, in order to improve soil quality properties and accelerate passive reforestation, should aim at the improvement of soil parameters related primarily to C and secondly to N cycle.

Definition of management zones for enhancing cultivated land conservation using combined spatial data.

PubMed

Li, Yan; Shi, Zhou; Wu, Hao-Xiang; Li, Feng; Li, Hong-Yi

2013-10-01

The loss of cultivated land has increasingly become an issue of regional and national concern in China. Definition of management zones is an important measure to protect limited cultivated land resource. In this study, combined spatial data were applied to define management zones in Fuyang city, China. The yield of cultivated land was first calculated and evaluated and the spatial distribution pattern mapped; the limiting factors affecting the yield were then explored; and their maps of the spatial variability were presented using geostatistics analysis. Data were jointly analyzed for management zone definition using a combination of principal component analysis with a fuzzy clustering method, two cluster validity functions were used to determine the optimal number of cluster. Finally one-way variance analysis was performed on 3,620 soil sampling points to assess how well the defined management zones reflected the soil properties and productivity level. It was shown that there existed great potential for increasing grain production, and the amount of cultivated land played a key role in maintaining security in grain production. Organic matter, total nitrogen, available phosphorus, elevation, thickness of the plow layer, and probability of irrigation guarantee were the main limiting factors affecting the yield. The optimal number of management zones was three, and there existed significantly statistical differences between the crop yield and field parameters in each defined management zone. Management zone I presented the highest potential crop yield, fertility level, and best agricultural production condition, whereas management zone III lowest. The study showed that the procedures used may be effective in automatically defining management zones; by the development of different management zones, different strategies of cultivated land management and practice in each zone could be determined, which is of great importance to enhance cultivated land conservation

Effects of livestock species and stocking density on accretion rates in grazed salt marshes

NASA Astrophysics Data System (ADS)

Nolte, Stefanie; Esselink, Peter; Bakker, Jan P.; Smit, Christian

2015-01-01

Coastal ecosystems, such as salt marshes, are threatened by accelerated sea-level rise (SLR). Salt marshes deliver valuable ecosystem services such as coastal protection and the provision of habitat for a unique flora and fauna. Whether salt marshes in the Wadden Sea area are able to survive accelerated SLR depends on sufficient deposition of sediments which add to vertical marsh accretion. Accretion rate is influenced by a number of factors, and livestock grazing was recently included. Livestock grazing is assumed to reduce accretion rates in two ways: (a) directly by increasing soil compaction through trampling, and (b) indirectly by affecting the vegetation structure, which may lower the sediment deposition. For four years, we studied the impact of two livestock species (horse and cattle) at two stocking densities (0.5 and 1.0 animal ha-1) on accretion in a large-scale grazing experiment using sedimentation plates. We found lower cumulative accretion rates in high stocking densities, probably because more animals cause more compaction and create a lower canopy. Furthermore, a trend towards lower accretion rates in horse-compared to cattle-grazed treatments was found, most likely because (1) horses are more active and thus cause more compaction, and (2) herbage intake by horses is higher than by cattle, which causes a higher biomass removal and shorter canopy. During summer periods, negative accretion rates were found. When the grazing and non-grazing seasons were separated, the impact of grazing differed among years. In summer, we only found an effect of different treatments if soil moisture (precipitation) was relatively low. In winter, a sufficiently high inundation frequency was necessary to create differences between grazing treatments. We conclude that stocking densities, and to a certain extent also livestock species, affect accretion rates in salt marshes. Both stocking densities and livestock species should thus be taken into account in management

Ecology of grazing lawns in Africa.

PubMed

Hempson, Gareth P; Archibald, Sally; Bond, William J; Ellis, Roger P; Grant, Cornelia C; Kruger, Fred J; Kruger, Laurence M; Moxley, Courtney; Owen-Smith, Norman; Peel, Mike J S; Smit, Izak P J; Vickers, Karen J

2015-08-01

Grazing lawns are a distinct grassland community type, characterised by short-stature and with their persistence and spread promoted by grazing. In Africa, they reveal a long co-evolutionary history of grasses and large mammal grazers. The attractiveness to grazers of a low-biomass sward lies in the relatively high quality of forage, largely due to the low proportion of stem material in the sward; this encourages repeat grazing that concomitantly suppresses tall-grass growth forms that would otherwise outcompete lawn species for light. Regular grazing that prevents shading and maintains sward quality is thus the cornerstone of grazing lawn dynamics. The strong interplay between abiotic conditions and disturbance factors, which are central to grazing lawn existence, can also cause these systems to be highly dynamic. Here we identify differences in growth form among grazing lawn grass species, and assess how compositional differences among lawn types, as well as environmental variables, influence their maintenance requirements (i.e. grazing frequency) and vulnerability to degradation. We also make a clear distinction between the processes of lawn establishment and lawn maintenance. Rainfall, soil nutrient status, grazer community composition and fire regime have strong and interactive influences on both processes. However, factors that concentrate grazing pressure (e.g. nutrient hotspots and sodic sites) have more bearing on where lawns establish. Similarly, we discuss the relevance of enhanced rates of nitrogen cycling and of sodium levels to lawn maintenance. Grazer community composition and density has considerable significance to grazing lawn dynamics; not all grazers are adapted to foraging on short-grass swards, and differences in body size and relative mouth dimensions determine which species are able to convert tall-grass swards into grazing lawns under different conditions. Hence, we evaluate the roles of different grazers in lawn dynamics, as well as the

77 FR 8219 - Coastal Zone Management Program: Illinois

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-14

... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Coastal Zone Management Program: Illinois AGENCY: Office of Ocean and Coastal Resource Management (OCRM), National Oceanic and... of Decision (ROD) for Federal Approval of the Illinois Coastal Management Program (ICMP). SUMMARY...

76 FR 57022 - Coastal Zone Management Program: Illinois

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-15

... DEPARTMENT OF COMMERCE National Oceanic And Atmospheric Administration Coastal Zone Management Program: Illinois AGENCY: Office of Ocean and Coastal Resource Management (OCRM), National Oceanic and... Resource Management. The DEIS assesses the environmental impacts associated with approval of the Illinois...

76 FR 80342 - Coastal Zone Management Program: Illinois

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-23

... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Coastal Zone Management Program: Illinois AGENCY: Office of Ocean and Coastal Resource Management (OCRM), National Oceanic and... Environmental Impact Statement. SUMMARY: NOAA's Office of Ocean and Coastal Resource Management (OCRM) announces...

Dynamical stabilization of grazing systems: An interplay among plant-water interaction, overgrazing and a threshold management policy.

PubMed

Costa, Michel Iskin da Silveira; Meza, Magno Enrique Mendoza

2006-12-01

In a plant-herbivore system, a management strategy called threshold policy is proposed to control grazing intensity where the vegetation dynamics is described by a plant-water interaction model. It is shown that this policy can lead the vegetation density to a previously chosen level under an overgrazing regime. This result is obtained despite both the potential occurrence of vegetation collapse due to overgrazing and the possibility of complex dynamics sensitive to vegetation initial densities and parameter uncertainties.

Tree cover changes in mamane (Sophora chrysophylla) forests grazed by sheep and cattle

Treesearch

Paul G. Scowcroft

1983-01-01

Using aerial photographs taken in 1954, 1965, and 1975, percentage of tree cover was determined for three sections of the sheep- and cattle-grazed mamane (Sophora chrysophylla) forest of Mauna Kea, Hawaii. In one section, the Ka 'ohe Game Management Area, where grazing by sheep was judged light, tree cover increased slightly during the 21-yr...

A critical analysis of the long-term impact (1936-2015) of grazing management on Land Degradation in a marginal, rural community of Southern Italy

NASA Astrophysics Data System (ADS)

Quaranta, Giovanni; Salvia, Rosanna; De Paola, Velia; Coluzzi, Rosa; Imbrenda, Vito; Simoniello, Tiziana

2017-04-01

Unsustainable grazing, one of the most diffused problem in land management at the global scale, is considered as a serious pressure on natural landscapes. Particularly in the Mediterranean agroforestry landscapes, unsustainable grazing is regarded as a key factor of degradation processes, mostly determined and exacerbated by evolving socioeconomic and environmental conditions at the local scale, revised agricultural policies and changing international market scenario. The Common Agricultural Policy set at the European level plays a powerful and twofold role in shaping the dynamics at local level. Measures adopted for Less Favoured Areas, for example, have stimulated grazing intensification based on financial supports whose effectiveness is shaped by the socioeconomic local context. At the same time, pasture-based livestock farming systems are considered priority habitats preserving traditional and high natural value farmlands in Mediterranean Europe. A sustainable management of pastures may also contribute to limit soil erosion and to mitigate land degradation. This paper critically analyses the drivers of change and the challenges facing a Mediterranean upland pastoralist systems in Southern Italy along a period of almost 80 years (1936-2015). The detailed case study highlights the linkages between the evolution of landscape, grazing management, locally adapted animal breeds and social capital. Historical forest maps, aerial imagery and satellite data at different spatial resolutions have been used to trace land use trajectories occurred during the investigated period within the study area. The integration in a GIS environment of the obtained results with diachronic detailed farm management surveys and semi-structured interviews, shows a strong link between land use changes and economic performances mainly connected to policy orientation. Along the time period considered, different adaptation strategies adopted by local actors are analysed leading to the present

Impacts of overgrazing in a long term traditional grazing ecosystem on vegetation around watering points in a semi-arid rangeland of North-Eastern Iran.

PubMed

Hassani, N; Asghari, H R; Frid, A S; Nurberdief, M

2008-07-01

In this study, the effects of livestock overgrazing on vegetation of the critical area around livestock watering points in a traditional grazing ecosystem was investigated on a semi-arid rangeland in North-East of Iran. Transects were placed in 8 geographical directions around watering points and samples were taken systematically. In each experimental plot, 4 m2, percentage of canopy cover, abundance, density and species richness of vegetation were calculated. The results of this study showed that the percentage of canopy cover, density and species richness were changed with distance from watering points. Critical area immediately adjacent to watering points was dominated by unpalatable Peganum harmala and contained of ruderal species such as Sophora sp. Adjacent to this was a zone dominated by species of low palatability such as Acantholimon sp. and Hulthemia persica. In areas most distant from watering points relative importance of moderately palatable species such as Artemisia herba-alba increased. These results show the negative impacts of overgrazing on vegetation and palatability in a traditional grazing ecosystem, which may indicate the necessity of a monitoring programme, to manage livestock grazing and watering points in North-East of Iran.

Impact of livestock grazing on abundance of Miridae and Reduviidae (Hemiptera) in crested wheatgrass pastures.

PubMed

O'Neill, Kevin M; Blodgett, Sue; Olson, Bret E; Miller, Richard S

2008-04-01

Miridae of the genera Labops and Irbisia, collectively referred to as "black grass bugs," can cause significant damage to wheatgrasses (Poaceae) of several genera on western North American rangeland. Another mirid in the same area, Capsus cinctus (Kolenati), causes damage to bluegrass (Poa spp.). Previous studies suggest that grazing management may reduce mirid populations on rangeland by eliminating preferred oviposition sites and reducing accumulations of litter that provide diurnal refuges for nymphs. We tested the hypothesis that grazing reduces mirid populations, along with those of Reduviidae, during a controlled grazing experiment. Densities of mirids and reduviids declined with increasing intensity of grazing, even though grazing occurred after the peak of mirid abundance each year. This suggests that declines in hemipteran densities resulted from grazing that occurred during previous years, perhaps because the most heavily grazed plots had the least plant litter. The results further confirm that grazing has the potential to control black grass bug populations, although the benefits could be potentially offset by negative impacts on beneficial insects such as reduviids.

Current status of coastal zone issues and management in China: a review.

PubMed

Cao, Wenzhi; Wong, Ming H

2007-10-01

This paper identifies and examines social-economic and environmental issues recently emerged in China's coastal zone. Evaluation of management scheme and progress in perspectives of coordinated legislation, institutional arrangement, public participation, capacity building, and scientific research (mainly coastal planning and functional zoning) in China's coastal zone are made. The Chinese government has made a significant effort in developing legislation for the coastal zone. Jurisdictional and zoning boundaries, and allocating use rights for coastal and marine resources have been established. State Oceanic Administration is the leading agency responsible for China's ocean policymaking and overall management of ocean and coastal affairs. A demonstrated project for integrated coastal management in Xiamen has been implemented, and is characterized as "decentralization" approach in decision-making process. In view of the above, comprehensive coastal management in China is a big challenge, facing with many difficulties. Finally, recommendations are raised for tackling these issues for China's coastal zone management.

Final Environmental Assessment for the Semiannual Joint Integrated Fires Exercises at Avon Park Air Force Range, Florida

DTIC Science & Technology

2006-04-01

spring that would have the potential to create wildfires. 3.11 Grazing Management : All alternatives would have minimal impact to grazing...3.12 Invasive Plant Management : All alternatives would have minimal impact to management . 3.13 Timber Management : All alternatives would have...food and fuel within the local communities. 3.18 Coastal Zone Management : The alternatives would be consistent with the Florida Coastal Zone

High intensity, short duration rotational grazing on reclaimed cool season fescue/legume pastures: I. System development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erickson, W.R.; Carlson, K.E.

The Pittsburg & Midway Coal Mining Co.`s ({open_quotes}P&M{close_quotes}) Midway Mine lies 50 miles south of Kansas City, Kansas, straddling the border of Kansas and Missouri. P&M actively mined the area until 1989, when the mine was closed and reclaimed. Approximately 3,750 acres of surface mined land were topsoiled and revegetated to cool season fescue/legume pasture. Various pasture management methods are being utilized to meet reclamation success standards and achieve final bond release. The effectiveness and costs of various cool season fescue/legume pasture management methods are evaluated and contrasted. These methods include sharecropping, bush hogging, burning and livestock grazing. It presentsmore » guidelines used to develop a site specific rotational livestock grazing programs with land owners or contractors, and local, state and federal agencies. Rotational grazing uses both cow/calf or feeder livestock operations. Key managerial elements used to control grazing activities, either by the landowner or a contractor, are reviewed. Methods used to determine stocking levels for successful rotational grazing on this type of pasture are presented. Rotational grazing of livestock has proven to be the most effective method for managing established cool season fescue/legume pastures at this site. Initial stocking rates of 1 A.U.M. per 5 acres have been modified to a current stocking rate of 1 A.U.M. per 2.5 acres. Supporting physical and chemical data are presented and discussed.« less

Use of Data Layering to Address Changes in Nitrogen Management Zone Delineation

Treesearch

D.W. Franzen; T. Nanna

2006-01-01

Use of N management zones appears to be a practical method of revealing dominant patterns of residual soil nitrate in North Dakota crop fields, where fall soil nitrate sampling is a common N management tool. Delineation of zone boundaries to date has been a largely subjective process. A weighted, classified method of delineating nitrogen management zones is presented....

Chapter 2: Livestock and Grazed Lands Emissions

USDA-ARS?s Scientific Manuscript database

A total of 342 MMT CO2 eq. of greenhouse gasses (GHGs) were emitted from livestock, managed livestock waste, and grazed land in 2013. This represents about 66% of total emissions from the agricultural sector, which totaled 516 MMT CO2 eq. Compared to the base line year (1990), emissions from livesto...

Rangeland Brush Estimation Toolbox (RaBET): An Approach for Evaluating Brush Management Conservation Efforts in Western Grazing Lands

NASA Astrophysics Data System (ADS)

Holifield Collins, C.; Kautz, M. A.; Skirvin, S. M.; Metz, L. J.

2016-12-01

There are over 180 million hectares of rangelands and grazed forests in the central and western United States. Due to the loss of perennial grasses and subsequent increased runoff and erosion that can degrade the system, woody cover species cannot be allowed to proliferate unchecked. The USDA-Natural Resources Conservation Service (NRCS) has allocated extensive resources to employ brush management (removal) as a conservation practice to control woody species encroachment. The Rangeland-Conservation Effects Assessment Project (CEAP) has been tasked with determining how effective the practice has been, however their land managers lack a cost-effective means to conduct these assessments at the necessary scale. An ArcGIS toolbox for generating large-scale, Landsat-based, spatial maps of woody cover on grazing lands in the western United States was developed through a collaboration with NRCS Rangeland-CEAP. The toolbox contains two main components of operation, image generation and temporal analysis, and utilizes simple interfaces requiring minimum user inputs. The image generation tool utilizes geographically specific algorithms developed from combining moderate-resolution (30-m) Landsat imagery and high-resolution (1-m) National Agricultural Imagery Program (NAIP) aerial photography to produce the woody cover scenes at the Major Land Resource (MLRA) scale. The temporal analysis tool can be used on these scenes to assess treatment effectiveness and monitor woody cover reemergence. RaBET provides rangeland managers an operational, inexpensive decision support tool to aid in the application of brush removal treatments and assessing their effectiveness.

Multimedia Delivery of Coastal Zone Management Training.

ERIC Educational Resources Information Center

Clark, M. J.; And Others

1995-01-01

Describes Coastal Zone Management (CZM) multimedia course modules, educational software written by the GeoData Institute at the University of Southamptom for an environmental management undergraduate course. Examines five elements that converge to create CZM multimedia teaching: course content, source material, a hardware/software delivery system,…

Allelopathic cover crop prior to seeding is more important than subsequent grazing/mowing in Grassland establishment

USGS Publications Warehouse

Milchunas, D.G.; Vandever, M.W.; Ball, L.O.; Hyberg, S.

2011-01-01

The effects of grazing, mowing, and type of cover crop were evaluated in a previous winter wheat-fallow cropland seeded to grassland under the Conservation Reserve Program in eastern Colorado. Prior to seeding, the fallow strips were planted to forage sorghum or wheat in alternating strips (cover crops), with no grazing, moderate to heavy grazing, and mowing (grazing treatments) superimposed 4 yr after planting and studied for 3 yr. Plots previously in wheat had more annual and exotic species than sorghum plots. Concomitantly, there were much greater abundances of perennial native grass and all native species in sorghum than wheat cropped areas. The competitive advantage gained by seeded species in sorghum plots resulted in large increases in rhizomatous western wheatgrass. Sorghum is known to be allelopathic and is used in crop agriculture rotations to suppress weeds and increase crop yields, consistent with the responses of weed and desired native species in this study. Grazing treatment had relatively minor effects on basal and canopy cover composition of annual or exotic species versus perennial native grass or native species. Although grazing treatment never was a significant main effect, it occasionally modified cover crop or year effects. Opportunistic grazing reduced exotic cheatgrass by year 3 but also decreased the native palatable western wheatgrass. Mowing was a less effective weed control practice than grazing. Vegetative basal cover and aboveground primary production varied primarily with year. Common management practices for revegetation/restoration currently use herbicides and mowing as weed control practices and restrict grazing in all stages of development. Results suggest that allelopathic cover crop selection and opportunistic grazing can be effective alternative grass establishment and weed control practices. Susceptibility, resistance, and interactions of weed and seeded species to allelopathic cover species/cultivars may be a fruitful area of

Managing the herbage utilisation and intake by cattle grazing rangelands

USDA-ARS?s Scientific Manuscript database

To be able to predict the performance of grazing cattle in extensive rangeland environments, herbage intake is paramount because it quantifies energy intake and performance. Nutrient demand of the animals is the major driver of herbage intake and characteristics of the sward dictate how this demand...

Impact of rotational grazing on management of gastrointestinal nematodes in weaned lambs.

PubMed

Burke, J M; Miller, J E; Terrill, T H

2009-07-07

Gastrointestinal nematode (GIN) control for 'natural' or organic lamb production is needed, especially where Haemonchus contortus is prevalent. The objective was to determine the impact of rotational grazing on GIN infection of weaned lambs. In year 1, naturally infected Katahdin lambs (120 days of age) were randomly assigned to graze (1) continuous bermudagrass (CB; n=14), (2) rotational bermudagrass moved every 3.5 days and returned to original plot 35 days later for three rotations (RB; n=14), or (3) rotational bermudagrass rotated when forage height fell below 10 cm (RBH; n=7) where first day of grazing=Day 0. In late summer, all lambs were supplemented with 500 g corn/SBM because of poor condition. The following year, similar animals were used and included the CB (n=18) and the RB (n=36) groups only. In both years, fecal egg counts (FECs) and blood packed cell volume (PCV) were determined every 7-14 days and body weight every 28 days. Individuals were dewormed with 0.5 g copper oxide wire particles (COWP) when FAMACHA score increased to 3 or more. Between 0 and 3 deworming treatments per lamb were necessary and there tended to be fewer RB than CB lambs dewormed by Day 84 for both years combined (P<0.001). Worm free tracer lambs were introduced to CB (n=6) and RB (n=8) plots following the last rotation during the first year to determine worm burdens after 20 days of grazing. Abomasal worm burden tended to be greater in RB than CB or RBH tracer lambs (P<0.10), but intestinal worm numbers were similar. Differences may be due to differences in grazing patterns among groups. Body weight gains were similar between CB and RB groups. Economic value between the CB and RB lambs was similar based on number of lambs that could have been marketed as organic. For both years, lambs relied exclusively on COWP for GIN control with the exception of one lamb. In summary, while there was a reduced incidence of deworming in the RB compared with the CB group of lambs, estimated

Impact of Daily Grazing Time on Dairy Cow Welfare—Results of the Welfare Quality® Protocol

PubMed Central

Wagner, Kathrin; Brinkmann, Jan; March, Solveig; Hinterstoißer, Peter; Warnecke, Sylvia; Schüler, Maximilian; Paulsen, Hans Marten

2017-01-01

Simple Summary It is often presumed that grazing dairy cows experience better welfare than those that are housed all year round. But is this really the case? In this study, we wanted to find out whether the daily amount of time cows spent on pasture affected their welfare. We used the Welfare Quality® assessment protocol for dairy cattle to measure cow welfare on 32 farms (organic and conventional) once in winter (=housing period) and once in summer (=grazing period, if provided). Farms were grouped according to daily grazing time (‘minor/zero’, ‘medium’, and ‘high’). In farms with grazing, overall welfare improved from winter to summer, whereas the situation in minor/zero grazing farms remained largely unchanged. While we found no overall effect of the amount of daily grazing time on cow welfare, the individual measures “% of cows with hairless patches” and “% of lame cows” received better scores in the high grazing farms. However, other measures e.g., related to water provision, scored worse in the grazing farms in summer as opposed to winter. We conclude that grazing offers a high potential to enhance dairy cow welfare during summer. However, beneficial effects are not guaranteed when the overall management does not satisfy the cows´ needs. Abstract Grazing provides livestock better opportunities to act out their species-specific behavior compared to restrictive stable conditions. The aim of the present study was to examine the effects of daily grazing time on welfare of dairy cows in organic and conventional farms based on the Welfare Quality® assessment protocol for dairy cattle (WQ®). Therefore, we applied the WQ® on 32 dairy farms (classified in 3 groups: Group 0, minor/zero grazing, n = 14; Group 1, medium grazing, n = 10; Group 2, high grazing, n = 8). We assessed the status of animal welfare once in winter and once in summer. For statistical analyses we used mixed models for repeated measures, with group, season, and their

Management applicability of the intermediate disturbance hypothesis across Mongolian rangeland ecosystems.

PubMed

Sasaki, Takehiro; Okubo, Satoru; Okayasu, Tomoo; Jamsran, Undarmaa; Ohkuro, Toshiya; Takeuchi, Kazuhiko

2009-03-01

The current growing body of evidence for diversity-disturbance relationships suggests that the peaked pattern predicted by the intermediate disturbance hypothesis (IDH) may not be the rule. Even if ecologists could quantify the diversity-disturbance relationship consistent with the IDH, the applicability of the IDH to land management has rarely been addressed. We examined two hypotheses related to the generality and management applicability of the IDH to Mongolian rangeland ecosystems: that the diversity-disturbance relationship varies as a function of landscape condition and that some intermediate scales of grazing can play an important role in terms of sustainable rangeland management through a grazing gradient approach. We quantified the landscape condition of each ecological site using an ordination technique and determined two types of landscape conditions: relatively benign and harsh environmental conditions. At the ecological sites characterized by relatively benign environmental conditions, diversity-disturbance relationships were generally consistent with the IDH, and maximum diversity was observed at some intermediate distance from the source of the grazing gradient. In contrast, the IDH was not supported at most (but not all) sites characterized by relatively harsh environmental conditions. The intermediate levels of grazing were generally located below the ecological threshold representing the points or zones at which disturbance should be limited to prevent drastic changes in ecological conditions, suggesting that there is little "conundrum" with regard to intermediate disturbance in the studied systems in terms of land management. We suggest that the landscape condition is one of the primary factors that cause inconsistencies in diversity-disturbance relationships. The ecological threshold can extend its utility in rangeland management because it also has the compatibility with the maintenance of species diversity. This study thus suggests that some

Variability in carbon dioxide fluxes among six winter wheat paddocks managed under different tillage and grazing practices

NASA Astrophysics Data System (ADS)

Wagle, Pradeep; Gowda, Prasanna H.; Northup, Brian K.; Turner, Kenneth E.; Neel, James P. S.; Manjunatha, Priyanka; Zhou, Yuting

2018-07-01

Carbon dioxide (CO2) fluxes from six winter wheat (Triticum aestivum L.) paddocks (grain only, graze-grain, and graze-out) managed under conventional till (CT) and no-till (NT) systems were synthesized for the 2016-2017 growing season to compare the magnitudes and seasonal dynamics of CO2 fluxes and to investigate among-site variability of CO2 fluxes. Large variations in CO2 fluxes were observed among paddocks. Maximum daily (7-day averages) net ecosystem CO2 exchange (NEE) ranged from -3.39 to -8.68 g C m-2, gross primary production (GPP) ranged from 7.33 to 16.92 g C m-2, and ecosystem respiration (ER) ranged from 5.85 to 9.98 g C m-2. Seasonal sums of NEE ranged from -137 to -542 g C m-2. Optimum photosynthetically active radiation (PAR), air temperature (Ta), and vapor pressure deficit (VPD) for NEE were approximately 1700 μmol m-2 s-1, 22 °C, and 1.25 kPa, respectively. Across-site analysis showed percent of canopy cover (Canopy%) was strongly correlated with NEE (R2 = 0.76) and ecosystem light use efficiency (ELUE, R2 = 0.76). Integration of PAR with leaf area index (LAI) and integration of Ta with dry biomass weight (DW) explained 81% and 74% of variations in GPP and ER, respectively. Remotely-sensed enhanced vegetation index (EVI) explained 66% and normalized difference vegetation index (NDVI) explained 69% of the variations in NEE. Integration of PAR with NDVI or EVI explained ∼80% of variations in GPP, while NDVI × Ta explained 58% of variations in ER. Results illustrated that differences in wheat canopies related to paddock management, as indicated by differences in DW, LAI, Canopy%, NDVI, and EVI, must be accounted for explaining among-site variability of CO2 fluxes. Long-term measurements from our clustered and paired eddy covariance towers will provide insights into the effects of tillage and different grazing practices on CO2 dynamics in winter wheat.

High intensity, short duration rotational grazing on reclaimed cool season tall fescue/legume pastures: II. Forage production, soil and plant tissue comparisons between grazed and ungrazed pastures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carlson, K.E.; Erickson, W.R.; Bonine, R.C.

The Midway Mine is located 50 miles south of Kansas City, Kansas straddling the border of Kansas and Missouri. The Pittsburg & Midway Coal Mining Co. mined the area until 1989, when the mine was closed and reclaimed. Approximately 3,750 acres were topsoiled and revegetated with a cool season tall fescue/legume pasture. High intensity, short duration rotational grazing has become the preferred management practice on these pastures. This study evaluated soil and vegetation data collected on 1,250 acres of pasture which was grazed by about 550 cow/calf units. Ongoing monitoring programs are evaluating the effects of rotational grazing. Soil testingmore » includes macro-nutrients, micro-nutrients and microbial activity. Plant tissue analyses monitor levels of principal macro-nutrients and micro-nutrients. Vegetation monitoring consists of measuring forage production. Results were contrasted between pregrazing and postgrazing, and grazed and ungrazed pasture. Agronomic data from the grazed versus ungrazed treatments documented the following results: (1) higher levels of plant tissue nitrate, phosphorus, potassium, calcium, magnesium, sodium and sulfur; (2) higher microbial activity; (3) similar levels of soil nitrate, phosphorus, potassium, calcium, magnesium, sodium and sulfur; and (4) increased biomass production.« less

Plant community dynamics in the shortgrass steppe 24 years after reversal of a grazing exclosure experiment

USDA-ARS?s Scientific Manuscript database

State and Transition Models are important decision-support tools for rangeland managers that suggest directional effects of both long-term grazing imposition and relaxation on plant community composition. However, most studies of the effects of grazing on semiarid rangelands evaluate only one direct...

Defining Steamside Management Zones or Riparian Buffers

Treesearch

Thomas M. Williams; Donald J. Lipscomb; Christopher J. Post

2004-01-01

Forestry Best Management Practices (BMPs) have been highly successful in protecting water quality throughout the Southeast. Numerous studies have found them to be effective in protecting water quality. Despite being mostly voluntary, compliance is generally about 90 percent across the region. Streamside Management Zones (SMZs) or riparian buffers are specified for...

The Effect of Different Type of Herbivores, Grazing Types and Grazing Intensities on Alpine Basiphillous Vegetation of the Romanian Carpathians

NASA Astrophysics Data System (ADS)

Ballová, Zuzana; Pekárik, Ladislav; Šibík, Jozef

2017-04-01

The major purpose of the present study was to test the hypothesis that there are significant differences in vegetation structure, plant species composition, and soil chemical properties in relation to type of grazing animals, various levels of grazing intensity and grazing type, and if potential differences alter with ecosystem productivity (increase in more productive ecosystems). The study was conducted in three mountain ranges of the Romanian Carpathians with a predominance of alkaline substrates (the Bucegi Mts, the Little Retezat Mts and the Ceahlău Massif). Statistical analyses were performed in R statistical software environment. The effects of grazing animals (cattle, horses and sheep), grazing types (fence, regular, irregular) and grazing intensity (low, medium, high) on the community structure were tested using ordination methods. In the case of soil properties, General Linear Mixed Model was applied. Special statistical approach eliminated the differences between the examined mountains and sites. Type of grazing animal does not significantly influence species cover but it is related to specific species occurrence. According to our results, grazing horses had similar effects as cattle compared to sheep. Grazing in restricted areas (surrounded by fence) and regular unrestricted grazing were more similar if compared to irregular grazing. When comparing the intensity of grazing, high and medium intensity were more similar to each other than to the low intensity grazing. Cattle grazed sites had significantly higher lichens cover, while the sheep patches were covered with increased overall herb layer (forbs, graminoids and low shrubs together). Medium grazing intensity decreased the lichens cover, cover of overall herb layer, and total vegetation cover compared to high and low grazing intensity. Grazing type had important impact on the lichens cover and cover of overall herb layer. The lichens cover appeared to decrease while the cover of overall herb layer

Managing Semi-Arid Rangelands for Carbon Storage: Grazing and Woody Encroachment Effects on Soil Carbon and Nitrogen

PubMed Central

Yusuf, Hasen M.; Treydte, Anna C.; Sauerborn, Jauchim

2015-01-01

High grazing intensity and wide-spread woody encroachment may strongly alter soil carbon (C) and nitrogen (N) pools. However, the direction and quantity of these changes have rarely been quantified in East African savanna ecosystem. As shifts in soil C and N pools might further potentially influence climate change mitigation, we quantified and compared soil organic carbon (SOC) and total soil nitrogen (TSN) content in enclosures and communal grazing lands across varying woody cover i.e. woody encroachment levels. Estimated mean SOC and TSN stocks at 0–40 cm depth varied across grazing regimes and among woody encroachment levels. The open grazing land at the heavily encroached site on sandy loam soil contained the least SOC (30 ± 2.1 Mg ha-1) and TSN (5 ± 0.57 Mg ha-1) while the enclosure at the least encroached site on sandy clay soil had the greatest mean SOC (81.0 ± 10.6 Mg ha-1) and TSN (9.2 ± 1.48 Mg ha-1). Soil OC and TSN did not differ with grazing exclusion at heavily encroached sites, but were twice as high inside enclosure compared to open grazing soils at low encroached sites. Mean SOC and TSN in soils of 0–20 cm depth were up to 120% higher than that of the 21–40 cm soil layer. Soil OC was positively related to TSN, cation exchange capacity (CEC), but negatively related to sand content. Our results show that soil OC and TSN stocks are affected by grazing, but the magnitude is largely influenced by woody encroachment and soil texture. We suggest that improving the herbaceous layer cover through a reduction in grazing and woody encroachment restriction are the key strategies for reducing SOC and TSN losses and, hence, for climate change mitigation in semi-arid rangelands. PMID:26461478

Explaining landholders' decisions about riparian zone management: the role of behavioural, normative, and control beliefs.

PubMed

Fielding, Kelly S; Terry, Deborah J; Masser, Barbara M; Bordia, Prashant; Hogg, Michael A

2005-10-01

Water quality is a key concern in the current global environment, with the need to promote practices that help to protect water quality, such as riparian zone management, being paramount. The present study used the theory of planned behaviour as a framework for understanding how beliefs influence decisions about riparian zone management. Respondents completed a survey that assessed their behavioural, normative, and control beliefs in relation to intentions to manage riparian zones on their property. The results of the study showed that, overall, landholders with strong intentions to manage their riparian zones differed significantly in terms of their beliefs compared to landholders who had weak intentions to manage their riparian zones. Strong intentions to manage riparian zones were associated with a favourable cost-benefit analysis, greater perceptions of normative support for the practice and lower perceptions of the extent to which barriers would impede management of riparian zones. It was also evident that willingness to comply with the recommendations of salient referents, beliefs about the benefits of riparian zone management and perceptions of the extent to which barriers would impede riparian zone management were most important for determining intentions to manage riparian zones. Implications for policy and extension practice are discussed.

Cool-season annual grasses interseeded into bermudagrass with improved cold-tolerance for grazing in the upper south

USDA-ARS?s Scientific Manuscript database

Bermudagrass [Cynodon dactylon (Pers.) L.] cultivars with improved cold tolerance can be utilized for grazing in the transition zone between the temperate northeast and subtropical southeast, but these bermudagrasses generally do not provide adequate growth for stocking until late May to early June....

Retrospective assessment of dryland soil stability in relation to grazing and climate change.

PubMed

Washington-Allen, Robert A; West, Neil E; Ramsey, R Douglas; Phillips, Debra H; Shugart, Herman H

2010-01-01

Accelerated soil erosion is an aspect of dryland degradation that is affected by repeated intense drought events and land management activities such as commercial livestock grazing. A soil stability index (SSI) that detects the erosion status and susceptibility of a landscape at the pixel level, i.e., stable, erosional, or depositional pixels, was derived from the spectral properties of an archived time series (from 1972 to 1997) of Landsat satellite data of a commercial ranch in northeastern Utah. The SSI was retrospectively validated with contemporary field measures of soil organic matter and erosion status that was surveyed by US federal land management agencies. Catastrophe theory provided the conceptual framework for retrospective assessment of the impact of commercial grazing and soil water availability on the SSI. The overall SSI trend was from an eroding landscape in the early drier 1970s towards stable conditions in the wetter mid-1980s and late 1990s. The landscape catastrophically shifted towards an extreme eroding state that was coincident with the "The Great North American Drought of 1988". Periods of landscape stability and trajectories toward stability were coincident with extremely wet El Niño events. Commercial grazing had less correlation with soil stability than drought conditions. However, the landscape became more susceptible to erosion events under multiple droughts and grazing. Land managers now have nearly a year warning of El Niño and La Niña events and can adjust their management decisions according to predicted landscape erosion conditions.

Grassland Fire and Cattle Grazing Regulate Reptile and Amphibian Assembly Among Patches

NASA Astrophysics Data System (ADS)

Larson, Danelle M.

2014-12-01

Fire and grazing are common management schemes of grasslands globally and are potential drivers of reptilian and amphibian (herpetofauna) metacommunity dynamics. Few studies have assessed the impacts of fire and cattle grazing on herpetofauna assemblages in grasslands. A patch-burn grazing study at Osage Prairie, MO, USA in 2011-2012 created landscape patches with treatments of grazing, fire, and such legacies. Response variables were measured before and after the application of treatments, and I used robust-design occupancy modeling to estimate patch occupancy and detection rate within patches, and recolonization and extinction (i.e., dispersal) across patches. I conducted redundancy analysis and a permuted multivariate analysis of variance to determine if patch type and the associated environmental factors explained herpetofauna assemblage. Estimates for reptiles indicate that occupancy was seasonally constant in Control patches ( ψ ~ 0.5), but declined to ψ ~ 0.15 in patches following the applications of fire and grazing. Local extinctions for reptiles were higher in patches with fire or light grazing ( ɛ ~ 0.7) compared to the controls. For the riparian herpetofaunal community, patch type and grass height were important predictors of abundance; further, the turtles, lizards, snakes, and adult amphibians used different patch types. The aquatic amphibian community was predicted by watershed and in-stream characteristics, irrespective of fire or grazing. The varying responses from taxonomic groups demonstrate habitat partitioning across multiple patch types undergoing fire, cattle grazing, and legacy effects. Prairies will need an array of patch types to accommodate multiple herpetofauna species.

Floodplains as a source of fine sediment in grazed landscapes: tracing the source of suspended sediment in the headwaters of an intensively managed agricultural landscape

NASA Astrophysics Data System (ADS)

Yu, M.; Rhoads, B. L.; Stumpf, A.

2017-12-01

The flux of fine sediment within agricultural watersheds is an important factor determining the environmental quality of streams and rivers. Despite this importance, the contributions of sediment sources to suspended sediment loads within intensively managed agricultural watersheds remain poorly understood. This study assesses the provenance of fine suspended sediment in the headwater portion of a river flowing through an agricultural landscape in Illinois. Sediment source samples were collected from five potential sources: streambanks, forested floodplain, grassland, and grazed floodplains. Event-based and aggregated suspended sediment samples were collected from the stream at the watershed outlet. Quantitative geochemical fingerprinting techniques and a mixing model were employed to estimate the relative contributions of sediment from five potential sources to the suspended sediment loads. Organic matter content, trace elements, and fallout radionuclides were used as potential tracers. Principal Component analysis was employed to complement the results and Monte Carlo random sampling routine was used to test the uncertainty in estimated contributions of sources to in-stream sediment loads. Results indicate that the majority of suspended sediment is derived from streambanks and grazed floodplains. Erosion of the floodplain both by surface runoff and by streambank erosion from lateral channel migration contributes to the production of fine sediment within the stream system. These results suggest that human activities, in this case grazing, have converted portions of floodplains, normally net depositional environments, into sources of fine sediments. Efforts to reduce fluxes of fine sediment in this intensively managed landscape should focus on degraded floodplain surfaces and eroding channel banks within heavily grazed reaches of the stream.

Nickel, Cobalt, Chromium and Copper in agricultural and grazing land soils of Europe

NASA Astrophysics Data System (ADS)

Albanese, Stefano; Sadeghi, Martiya; De Vivo, Benedetto; Lima, Annamaria; Cicchella, Domenico; Dinelli, Enrico

2014-05-01

In the framework of the GEMAS (Geochemical Mapping of Agricultural and Grazing Land Soils) project, concentrations of Ni, Co, Cu and Cr were determined for the whole available dataset (2218 samples of agricultural soil and 2127 samples of grazing land soil) covering a total area of 5.6 million sq km all over Europe. The distribution pattern of Ni in the European soils (both agricultural and grazing land soils) shows the highest concentrations in correspondence with the Mediterranean area (especially in Greece, the Balcan Peninsula and NW Italy) with average values generally ranging between 40 mg/kg and 140 mg/kg and anomalous areas characterized by peaks higher than 2400 mg/kg. Concentrations between 10 mg/kg and 40 mg/kg characterize Continental Europe north of Alps and, partly, the Scandinavian countries. Lower concentrations (< 10 mg/kg) occurs near the Trans-European Suture Zone, one of the main tectonic borders in Europe, and they are limited on the south by the maximum extent limit of the last glaciation. Cobalt and Cr show distribution patterns similar to Ni in both agricultural and grazing land soils. The maximum concentration peaks of Cobalt and Cr rise up to respectively 126 mg/kg and 696 mg/kg in agricultural soils and up to 255 mg/kg and 577 mg/kg in grazing land soils. Copper distribution in the soils collected across Europe, although has a general correspondence with the patterns of Ni, Co, Cr, shows some peculiarities. Specifically, Cu is characterized by high concentration values (up to 395 mg/kg in agricultural soils and 373 mg/kg in Grazing land soils) also in correspondence with the Roman Comagmatic Province and the south western coast of France characterized by a wide spread of vineyards.

A Comparison of Management Strategies in the Oak Woodlands of Spain and California

Treesearch

Lynn Huntsinger; James W. Bartolome; Paul F. Starrs

1991-01-01

The characteristics, uses, and management of oak woodlands and savannas in California and southern Spain are compared. There are many similarities between the Spanish dehesa and the California oak woodland. Both are located in Mediterranean climate zones, and are used predominantly for livestock grazing. However the Spanish dehesa is a more diverse and long-standing...

Successive sheep grazing reduces population density of Brandt's voles in steppe grassland by altering food resources: a large manipulative experiment.

PubMed

Li, Guoliang; Yin, Baofa; Wan, Xinrong; Wei, Wanhong; Wang, Guiming; Krebs, Charles J; Zhang, Zhibin

2016-01-01

Livestock grazing has shaped grassland ecosystems around the world. Previous studies indicated grazing showed various impacts on small rodents; however, most studies were conducted over 1-2 years without controlling for confounding factors such as immigration/emigration and predation in rodents. Brandt's voles (Lasiopodomys brandtii) are generally recognized as pests because of food overlap with domestic herbivores, but are also important for biodiversity conservation because they provide nests or food to many birds. Fully understanding the ecological relationship between domestic herbivores and small mammals is essential to making ecosystem management decisions. To address these needs, we carried out a field experiment during the period 2010-2013 to assess the effects of sheep grazing on vegetation and the population density of Brandt's voles along a gradient of three grazing intensities by using 12 large-scale enclosures. Responses of Brandt's voles to livestock grazing varied with grazing intensity and year. As compared to the control group, sheep grazing had no effect on vole abundance in the first year but an overall negative effect on vole abundance in the following 3 years. Successive grazing caused decreases in survival and male body mass of voles, but had no significant effect on fecundity. Negative effects of grazing were associated with a grazing-induced deterioration in both food quantity (reflected by biomass and cover of less-preferred plants), and food quality (measured by tannin and total phenol content). Our findings highlight the urgent need for more flexible management of yearly rotational grazing to optimize livestock production while maintaining species diversity and ecosystem health.

Density and success of bird nests relative to grazing on western Montana grasslands

USGS Publications Warehouse

Fondell, Thomas F.; Ball, I.J.

2004-01-01

Grassland birds are declining at a faster rate than any other group of North American bird species. Livestock grazing is the primary economic use of grasslands in the western United States, but the effects of this use on distribution and productivity of grassland birds are unclear. We examined nest density and success of ground-nesting birds on grazed and ungrazed grasslands in western Montana. In comparison to grazed plots, ungrazed plots had reduced forb cover, increased litter cover, increased litter depth, and increased visual obstruction readings (VOR) of vegetation. Nest density among 10 of 11 common bird species was most strongly correlated with VOR of plots, and greatest nest density for each species occurred where mean VOR of the plot was similar to mean VOR at nests. Additionally, all bird species were relatively consistent in their choice of VOR at nests despite substantial differences in VOR among plots. We suggest that birds selected plots based in part on availability of suitable nest sites and that variation in nest density relative to grazing reflected the effect of grazing on availability of nest sites. Nest success was similar between grazed plots and ungrazed plots for two species but was lower for nests on grazed plots than on ungrazed plots for two other species because of increased rates of predation, trampling, or parasitism by brown-headed cowbirds (Molothrus ater). Other species nested almost exclusively on ungrazed plots (six species) or grazed plots (one species), precluding evaluation of the effects of grazing on nest success. We demonstrate that each species in a diverse suite of ground-nesting birds preferentially used certain habitats for nesting and that grazing altered availability of preferred nesting habitats through changes in vegetation structure and plant species composition. We also show that grazing directly or indirectly predisposed some bird species to increased nesting mortality. Management alternatives that avoid

The important role of scattered trees on the herbaceous diversity of a grazed Mediterranean dehesa

NASA Astrophysics Data System (ADS)

López-Sánchez, Aida; San Miguel, Alfonso; López-Carrasco, Celia; Huntsinger, Lynn; Roig, Sonia

2016-10-01

Scattered trees are considered keystone structures and play an important role in Mediterranean sylvopastoral systems. Such systems are associated with high biodiversity and provide important natural resources and ecosystem services. In this study, we measured the contribution of scattered trees and different grazing management (cattle, sheep and wildlife only) to the diversity of the grassland sward in a dehesa (open holm oak woodland) located in Central Spain. We analyzed alpha and beta diversity through measurement of species richness, Shannon-Wiener, and Whittaker indices, respectively; and the floristic composition of the herb layer using subplots within two adjacent plots (trees present vs. trees absent) under three different grazing management regimes, including wildlife only, during a year. We found a 20-30% increment in the alpha diversity of wooded plots, compared to those without trees, regardless of grazing management. All beta indices calculated showed more than 60% species turnover. Wooded plots were occupied by different herbaceous species in different heterogeneous microsites (under the canopy, in the ecotone or on open land) created by the trees. Livestock grazing modified species composition (e.g. more nitrophilous species) compared to wildlife only plots. In addition to all their other benefits, trees are important to maintaining grassland diversity in Mediterranean dehesas.

Linking remote-sensing and ecosystem services modeling to support and assess management for regenerative grazing in the South Gobi, Mongolia

NASA Astrophysics Data System (ADS)

Chaplin-Kramer, R.; Kowal, V. A.; Sharp, R.

2017-12-01

Managing and monitoring supply chain sustainability is a major challenge and opportunity for business, especially in rangelands, heavily managed and often degraded natural systems that provide significant resources and raw materials for production. One of the largest and most threatened rangeland systems in the world is in Mongolia, which has seen a rapid rise in grazing pressure due to increasing global demand for cashmere along with privatization of a formerly government-run livestock industry. A new opportunity is emerging for remote-sensing to improve the management decisions of the producers and their incentive-setters, leading to a more sustainable rangeland system and better outcomes for biodiversity and people in this unique and imperiled landscape. Oyu Tolgoi (OT), the Mongolian subsidiary of the mining company Rio Tinto, in cooperation with Kering, an apparel conglomerate that sources cashmere from the region, are providing financial incentives to improve grazing patterns through a Sustainable Cashmere program, in order to restore the degraded rangeland ecosystem in the Gobi desert region. We present a framework and approach for predicting the effect of changing grazing practices on biodiversity and ecosystem services, which we are developing into decision-support tools for OT, Kering, and their local partner Wildlife Conservation Society to quantify the impacts of their programs and where these interventions will have greatest benefit. Our approach integrates remote-sensing and ecosystem modeling to scale up field monitoring data and forecast future impacts. Our rangeland production model, based on the soil-vegetation model CENTURY and the livestock model GRAZPLAN, predicts biomass production and plant species composition changes, and can feed into ecosystem services models such as soil retention and water regulation in the InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) software suite. This presents a significant advance in ecosystem

[Defining of wheat growth management zones based on remote sensing and geostatistics].

PubMed

Huang, Yan; Zhu, Yan; Ma, Meng-Li; Wang, Hang; Cao, Wei-Xing; Tian, Yong-Chao

2011-02-01

Taking the winter wheat planting areas in Rugao City and Haian County of Jiangsu Province as test objects, the clustering defining of wheat growth management zones was made, based on the spatial variability analysis and principal component extraction of the normalized difference vegetation index (NDVI) data calculated from the HJ-1A/B CCD images (30 m resolution) at different growth stages of winter wheat, and of the soil nutrient indices (total nitrogen, organic matter, available phosphorus, and available potassium). The results showed that the integration of the NDVI at heading stage with above-mentioned soil nutrient indices produced the best results of wheat growth management zone defining, with the variation coefficients of NDVI and soil nutrient indices in each defined zone ranged in 4.5% -6.1% and 3.3% -87.9%, respectively. However, the variation coefficients were much larger when the wheat growth management zones were defined individually by NDVI or by soil nutrient indices, suggesting that the newly developed defining method could reduce the variability within the defined management zones and improve the crop management precision, and thereby, contribute to the winter wheat growth management and process simulation at regional scale.

Nonlocal grazing in patterned ecosystems.

PubMed

Siero, E

2018-01-07

Many ecosystems exhibit gapped, labyrinthine, striped or spotted patterns. Important examples are vegetation patterns in drylands: these patterns are viewed as precursors of a catastrophic transition to a degraded state. A possible source of degradation is overgrazing, but many current spatially extended models include grazing in a local linear way. In this article nonlocal grazing responses are derived, taking into account (1) how many consumers there are (demographic response) (2) where they are (aggregative response) and (3) how much they forage (functional response). Different assumptions lead to different grazing responses, the type of grazing has a large influence on how ecosystems adapt to changing environmental conditions. In dryland simulations the different types of grazing are shown to alter the desertification process driven by decreasing rainfall. A sufficiently strong aggregative response leads to the suppression of vegetation patterns, nuancing their role as generic early warning signals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Relationships among rotational and conventional grazing systems, stream channels, and macroinvertebrates

USGS Publications Warehouse

Raymond, K.L.; Vondracek, B.

2011-01-01

Cattle grazing in riparian areas can reduce water quality, alter stream channel characteristics, and alter fish and macroinvertebrate assemblage structure. The U.S. Department of Agriculture, Natural Resources Conservation Services has recommended Rotational Grazing (RG) as an alternative management method on livestock and dairy operations to protect riparian areas and water quality. We evaluated 13 stream channel characteristics, benthic macroinvertebrate larvae (BML), and chironomid pupal exuviae (CPE) from 18 sites in the Upper Midwest of the United States in relation to RG and conventional grazing (CG). A Biotic Composite Score comprised of several macroinvertebrate metrics was developed for both the BML assemblage and the CPE assemblage. Multi-Response Permutation Procedures (MRPP) indicated a significant difference in stream channel characteristics between RG and CG. Nonmetric Multidimensional Scaling indicated that RG sites were associated with more stable stream banks, higher quality aquatic habitat, lower soil compaction, and larger particles in the streambed. However, neither MRPP nor Mann-Whitney U tests demonstrated a difference in Biotic Composite Scores for BML or CPE along RG and CG sites. The BML and CPE metrics were significantly correlated, indicating that they were likely responding to similar variables among the study sites. Although stream channel characteristics appeared to respond to grazing management, BML and CPE may have responded to land use throughout the watershed, as well as local land use. ?? 2011 Springer Science+Business Media B.V. (outside the USA).

Seasonality constraints to livestock grazing intensity.

PubMed

Fetzel, Tamara; Havlik, Petr; Herrero, Mario; Erb, Karl-Heinz

2017-04-01

Increasing food production is essential to meet the future food demand of a growing world population. In light of pressing sustainability challenges such as climate change and the importance of the global livestock system for food security as well as GHG emissions, finding ways to increasing food production sustainably and without increasing competition for food crops is essential. Yet, many unknowns relate to livestock grazing, in particular grazing intensity, an essential variable to assess the sustainability of livestock systems. Here, we explore ecological limits to grazing intensity (GI; i.e. the fraction of net primary production consumed by grazing animals) by analysing the role of seasonality in natural grasslands. We estimate seasonal limitations to GI by combining monthly net primary production data and a map of global livestock distribution with assumptions on the length of nonfavourable periods that can be bridged by livestock (e.g. by browsing dead standing biomass, storage systems or biomass conservation). This allows us to derive a seasonality-limited potential GI, which we compare with the GI prevailing in 2000. We find that GI in 2000 lies below its potential on 39% of the total global natural grasslands, which has a potential for increasing biomass extraction of up to 181 MtC/yr. In contrast, on 61% of the area GI exceeds the potential, made possible by management. Mobilizing this potential could increase milk production by 5%, meat production by 4% or contribute to free up to 2.8 Mio km² of grassland area at the global scale if the numerous socio-ecological constraints can be overcome. We discuss socio-ecological trade-offs, which may reduce the estimated potential considerably and require the establishment of sound monitoring systems and an improved understanding of livestock system's role in the Earth system. © 2017 John Wiley & Sons Ltd.

Winter grazing decreases wildfire risk, severity, and behavior in semi-arid sagebrush rangelands

USDA-ARS?s Scientific Manuscript database

Wildfires are an ecological and economic risk for many semi-arid rangelands which has resulted in increased pressure for pre-suppression management of fuels. In rangelands, fuel management treatment options are limited by costs. We evaluated winter grazing as a tool to manage fuels and alter fire ...

36 CFR 293.7 - Grazing of livestock.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Grazing of livestock. 293.7...-PRIMITIVE AREAS § 293.7 Grazing of livestock. (a) The grazing of livestock, where such use was established..., shall be permitted to continue under the general regulations covering grazing of livestock on the...

Formulating a coastal zone health metric for landuse impact management in urban coastal zones.

PubMed

Anilkumar, P P; Varghese, Koshy; Ganesh, L S

2010-11-01

The need for ICZM arises often due to inadequate or inappropriate landuse planning practices and policies, especially in urban coastal zones which are more complex due to the larger number of components, their critical dimensions, attributes and interactions. A survey of literature shows that there is no holistic metric for assessing the impacts of landuse planning on the health of a coastal zone. Thus there is a need to define such a metric. The proposed metric, CHI (Coastal zone Health Indicator), developed on the basis of coastal system sustainability, attempts to gauge the health status of any coastal zone. It is formulated and modeled through an expert survey and pertains to the characteristic components of coastal zones, their critical dimensions, and relevant attributes. The proposed metric is applied to two urban coastal zones and validated. It can be used for more coast friendly and sustainable landuse planning/masterplan preparation and thereby for the better management of landuse impacts on coastal zones. Copyright 2010 Elsevier Ltd. All rights reserved.

25 CFR 167.11 - Tenure of grazing permits.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Tenure of grazing permits. (a) All active regular grazing permits shall be for one year and shall be... § 167.8 may become a livestock operator by obtaining an active grazing permit through negotiability or... handle each matter of unused grazing permit or portions of grazing permits on individual merits. Where...

Social capital, collective action, and communal grazing lands in Uganda

PubMed Central

Call, Maia; Jagger, Pamela

2018-01-01

Recent scholars have found that collective action can be harnessed to sustainably manage common property, contrary to longstanding hypotheses that without effective external regulation community members will exploit communal resources. Researchers have also found that social capital, in addition to biophysical conditions and community attributes, is an important element of successful collective action. However, few studies exploring this topic have specifically examined communal grazing land, which is a critical component of rural livelihoods in many parts of the developing world. To address this gap, we explore the role that collective action plays in maintaining communal grazing lands through bridging, bonding, and linking social capital. In cases where the community does have communal grazing lands, we also explore the role of social capital in determining the condition of the land and the inclusiveness of access. Our analyses draw upon a community-level dataset composed of Uganda RePEAT survey data linked with high resolution gridded socio-environmental data. We observe that strong community bonds are associated with higher odds of successful collective action. However, increased links to external market forces may decrease the odds of successful collective action. These findings provide additional evidence for the complex relationship between social capital, collective action, and common property natural resource management. PMID:29377036

The impact of buffer strips and stream-side grazing on small mammals in southwestern Wisconsin

USGS Publications Warehouse

Chapman, Erik W.; Ribic, C.A.

2002-01-01

The practice of continuously grazing cattle along streams has caused extensive degradation of riparian habitats. Buffer strips and managed intensive rotational grazing (MIRG) have been proposed to protect and restore stream ecosystems in Wisconsin. However, the ecological implications of a switch from traditional livestock management to MIRG or buffer strip establishment have not been investigated. Differences in small mammal communities associated with riparian areas on continuously grazed and MIRG pastures, as well as vegetative buffer strips adjacent to row crops, were investigated in southwestern Wisconsin during May-September 1997 and 1998. More species (mean of 6-7) were found on the buffer sites than on the pasture sites (mean of 2-5). Total small mammal abundance on buffer sites was greater than on the pastures as well: there were 3-5 times as many animals on the buffer sites compared to the pasture sites, depending on year. There were no differences in species richness or total abundance between MIRG and continuously grazed pastures in either year. Total small mammal abundance was greater near the stream than away from the stream, regardless of farm management practice but there were no differences in species richness. Buffer strips appear to support a particularly rich and abundant small mammal community. Although results did not detect a difference in small mammal use between pasture types, farm-wide implications of a conversion from continuous to MIRG styles of grazing may benefit small mammals indirectly by causing an increase in the prevalence of pasture in the agricultural landscape.

Livestock Grazing, Golden Trout, and Streams in the Golden Trout Wilderness, California: Impacts and Management Implications

Treesearch

R. Knapp; K. Matthews

1996-01-01

Impacts of livestock grazing on California golden trout Oncorhynchus rnykiss aguabonita and their habitat were studied inside and outside of livestock exclosures in the Golden Trout Wilderness, California. In two consecutive years, the majority of stream physical characteristics showed large differences between grazed and ungrazed areas, and the directions of these...

Genetic strain and diet effects on grazing behavior, pasture intake, and milk production.

PubMed

Sheahan, A J; Kolver, E S; Roche, J R

2011-07-01

Understanding how dairy cows adjust their grazing behavior in response to feed supplements is important for the development of management strategies that optimize profit from supplementation. New Zealand Holstein-Friesian (HF) cows have been selected for milk production on a predominantly pasture-based diet; in comparison, HF cows of North American (NA) ancestry have been selected almost exclusively for milk yield and fed diets high in nonfiber carbohydrates (NFC). We hypothesized, therefore, that supplementation would have differing effects on grazing behavior, pasture dry matter intake (DMI), and milk production in these genetic strains at peak, mid, and late lactation. A study was conducted over 2 consecutive lactations, with NA and NZ cows randomly allocated at calving to 0, 3, or 6 kg of dry matter/day concentrate plus unrestricted access to pasture. Pasture DMI, milk production, and grazing behavior were recorded at peak, mid, and late lactation. Concentrates were fed in equal amounts at morning and afternoon milking. The NA cows produced more milk and milk components, and had a greater pasture DMI, despite spending less time grazing. Declines in time spent grazing and pasture DMI were associated with increasing concentrate DMI. Grazing behavior following morning supplementation was different from that recorded following afternoon supplementation. Grazing ceased following morning supplementation before rumen fill could be a limiting factor, and the length of the grazing interval was inversely proportional to the amount of concentrate offered; these results suggest that physiological rather than physical stimuli were responsible for grazing cessation. The decrease in time spent grazing with increasing concentrate DMI is consistent with changes in neuroendocrine factors secreted in response to the presence of food in the digestive tract or with circulating products of digestion. After afternoon supplementation, sunset signaled the end of grazing irrespective of

23 CFR 630.1106 - Policy and procedures for work zone safety management.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 23 Highways 1 2011-04-01 2011-04-01 false Policy and procedures for work zone safety management... Policy and procedures for work zone safety management. (a) Each agency's policy and processes, procedures... established in accordance with 23 CFR 630.1006, shall include the consideration and management of road user...

Long-term grazing effects on vegetation characteristics and soil properties in a semiarid grassland, northern China.

PubMed

Zhang, Jing; Zuo, Xiaoan; Zhou, Xin; Lv, Peng; Lian, Jie; Yue, Xiyuan

2017-05-01

Understanding the responses of vegetation characteristics and soil properties to grazing disturbance is useful for grassland ecosystem restoration and management in semiarid areas. Here, we examined the effects of long-term grazing on vegetation characteristics, soil properties, and their relationships across four grassland types (meadow, Stipa steppe, scattered tree grassland, and sandy grassland) in the Horqin grassland, northern China. Our results showed that grazing greatly decreased vegetation cover, aboveground plant biomass, and root biomass in all four grassland types. Plant cover and aboveground biomass of perennials were decreased by grazing in all four grasslands, whereas grazing increased the cover and biomass of shrubs in Stipa steppe and of annuals in scattered tree grassland. Grazing decreased soil carbon and nitrogen content in Stipa steppe and scattered tree grassland, whereas soil bulk density showed the opposite trend. Long-term grazing significantly decreased soil pH and electrical conductivity (EC) in annual-dominated sandy grassland. Soil moisture in fenced and grazed grasslands decreased in the following order of meadow, Stipa steppe, scattered tree grassland, and sandy grassland. Correlation analyses showed that aboveground plant biomass was significantly positively associated with the soil carbon and nitrogen content in grazed and fenced grasslands. Species richness was significantly positively correlated with soil bulk density, moisture, EC, and pH in fenced grasslands, but no relationship was detected in grazed grasslands. These results suggest that the soil carbon and nitrogen content significantly maintains ecosystem function in both fenced and grazed grasslands. However, grazing may eliminate the association of species richness with soil properties in semiarid grasslands.

Multi-decadal impacts of grazing on soil physical and biogeochemical properties in southeast Utah

USGS Publications Warehouse

Neff, J.C.; Reynolds, R.L.; Belnap, J.; Lamothe, P.

2005-01-01

Many soils in southeastern Utah are protected from surface disturbance by biological soil crusts that stabilize soils and reduce erosion by wind and water. When these crusts are disturbed by land use, soils become susceptible to erosion. In this study, we compare a never-grazed grassland in Canyonlands National Park with two historically grazed sites with similar geologic, geomorphic, and geochemical characteristics that were grazed from the late 1800s until 1974. We show that, despite almost 30 years without livestock grazing, surface soils in the historically grazed sites have 38-43% less silt, as well as 14-51% less total elemental soil Mg, Na, P, and Mn content relative to soils never exposed to livestock disturbances. Using magnetic measurement of soil magnetite content (a proxy for the stabilization of far-traveled eolian dust) we suggest that the differences in Mg, Na, P, and Mn are related to wind erosion of soil fine particles after the historical disturbance by livestock grazing. Historical grazing may also lead to changes in soil organic matter content including declines of 60-70% in surface soil C and N relative to the never-grazed sites. Collectively, the differences in soil C and N content and the evidence for substantial rock-derived nutrient loss to wind erosion implies that livestock grazing could have long-lasting effects on the soil fertility of native grasslands in this part of southeastern Utah. This study suggests that nutrient loss due to wind erosion of soils should be a consideration for management decisions related to the long-term sustainability of grazing operations in arid environments.

7 CFR 760.305 - Eligible grazing losses.

Code of Federal Regulations, 2012 CFR

2012-01-01

... grazing losses. (a) A grazing loss due to drought is eligible for LFP only if the grazing loss for the... of grazing land or pastureland for the county, rated by the U.S. Drought Monitor as having a: (i) D2 (severe drought) intensity in any area of the county for at least 8 consecutive weeks during the normal...

7 CFR 760.305 - Eligible grazing losses.

Code of Federal Regulations, 2014 CFR

2014-01-01

... grazing losses. (a) A grazing loss due to drought is eligible for LFP only if the grazing loss for the... of grazing land or pastureland for the county, rated by the U.S. Drought Monitor as having a: (i) D2 (severe drought) intensity in any area of the county for at least 8 consecutive weeks during the normal...

7 CFR 760.305 - Eligible grazing losses.

Code of Federal Regulations, 2011 CFR

2011-01-01

... grazing losses. (a) A grazing loss due to drought is eligible for LFP only if the grazing loss for the... of grazing land or pastureland for the county, rated by the U.S. Drought Monitor as having a: (i) D2 (severe drought) intensity in any area of the county for at least 8 consecutive weeks during the normal...

7 CFR 760.305 - Eligible grazing losses.

Code of Federal Regulations, 2013 CFR

2013-01-01

... grazing losses. (a) A grazing loss due to drought is eligible for LFP only if the grazing loss for the... of grazing land or pastureland for the county, rated by the U.S. Drought Monitor as having a: (i) D2 (severe drought) intensity in any area of the county for at least 8 consecutive weeks during the normal...

Livestock grazing not detrimental to meadow wildflowers

Treesearch

Raymond D. Ratliff

1972-01-01

Wildflower growth, meadow conditions, and grazing methods were compared in the Bogard area, Lassen National Forest, northeastern California. The two grazing methods were rest-rotation, in which range units are periodically rested from grazing, and free-choice, in which range units are not provided any rest periods from use. The results suggest that grazing per se need...

Long-term modeling of the forest-grassland ecotone in the French Alps: implications for land management and conservation.

PubMed

Carlson, Bradley Z; Renaud, Julien; Biron, Pierre Eymard; Choler, Philippe

2014-07-01

Understanding decadal-scale land-cover changes has the potential to inform current conservation policies. European mountain landscapes that include numerous protected areas provide a unique opportunity to weigh the long-term influences of land-use practices and climate on forest-grassland ecotone dynamics. Aerial photographs from four dates (1948, 1978, 1993, and 2009) were used to quantify the extent of forest and grassland cover at 5-m resolution across a 150-km2 area in a protected area of the southwestern French Alps. The study area included a grazed zone and a nongrazed zone that was abandoned during the 1970s. We estimated time series of a forestation index (FI) and analyzed the effects of elevation and grazing on FI using a hierarchical linear mixed effect model. Forest extent (composed primarily of mountain pine, Pinus uncinata) expanded from 50.6 km2 in 1948 to 85.5 km2 in 2009, i.e., a 23% increase in relative cover at the expense of grassland communities. Over the sixty-year period, the treeline rose by 118 m, from 1564 to 1682 m. Rapid forest expansion within the nongrazed zone followed the cessation of logging activities and was likely accelerated by climate warming during the 1980s. Within the grazed zone, the maintained presence of sheep did not fully counteract mountain pine expansion and led to highly contrasting rates of land-cover change based on the location of shepherds' cabins and water sources. Projections of FI for 2030 showed remnant patches of intensively used grasslands interspersed in a densely forested matrix. Our analysis of mountain land-cover dynamics provided strong evidence for forest encroachment into grassland habitat despite consistent grazing pressure. This pattern may be attributed to the disappearance of traditional land-use practices such as shrub burning and removal. Our findings prompt land managers to reconsider their initial conservation priority (i.e., the protection of a renowned mountain pine forest) and to implement

Semi-arid grassland bird responses to patch-burn grazing and drought

USGS Publications Warehouse

Skagen, Susan K.; Augustine, David J.; Derner, Justin D.

2018-01-01

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 and 2012. Although no simple direct relationship to patch-burn grazing treatment existed, habitat selection depended on precipitation- and management-induced vegetation conditions and spatial scale. All species selected taller-than-expected vegetation at the nest site, whereas at the territory scale, horned larks and McCown’s longspurs selected areas with low vegetation height and sparse cover of tall plants (taller than the dominant shortgrasses). Buntings nested primarily in unburned grassland under average rainfall. Larks and longspurs shifted activity from patch burns during average precipitation (2011) to unburned pastures during drought (2012). Daily survival rate (DSR) of nests varied with time in season, species, weather, and vegetation structure. Daily survival rate of McCown’s longspur nests did not vary with foliar cover of relatively tall vegetation at the nest under average precipitation but declined with increasing cover during drought. At the 200-m scale, increasing cover of shortgrasses, rather than taller plant species, improved DSR of larks and longspurs. These birds experience tradeoffs in the selection of habitat at different spatial scales: tall structure at nests may reduce visual detection by predators and provide protection from sun, wind, and rain, yet

Low intensity, mixed livestock grazing improves the breeding abundance of a common insectivorous passerine.

PubMed

Evans, Darren M; Redpath, Stephen M; Evans, Sharon A; Elston, David A; Gardner, Charles J; Dennis, Peter; Pakeman, Robin J

2006-12-22

Livestock grazing is a major driver of ecosystem change and has been associated with significant declines in various bird species in Britain and worldwide. However, there is little experimental evidence to show how grazing affects bird populations. We manipulated livestock densities in a replicated field experiment and found that mixed sheep and cattle grazing, at low intensity, improved the breeding abundance of a common upland passerine, the meadow pipit Anthus pratensis, after two years. Plots stocked with sheep alone (at high or low density) or not stocked at all held fewer pipit territories. Despite a year-on-year decline in pairs of meadow pipits in intensively grazed plots, we found no effect of sheep number on breeding abundance. Our results support the hypothesis that mixed species of herbivores generate greater heterogeneity in vegetation structure, which modifies prey availability, resulting in a greater abundance of birds. The results of our study should inform the management of grassland areas and enhance the abundance of some bird species, particularly in areas that have seen significant shifts from mixed livestock grazing to grazing dominated by single species of animals.

Grazing sericea lespedeza for control of gastrointestinal nematodes in lambs

USDA-ARS?s Scientific Manuscript database

Alternatives to chemical dewormers are needed to counter anthelmintic resistance and improve organic management systems. The objective was to examine the effectiveness of grazing sericea lespedeza (SL) compared with grass pastures for control of gastrointestinal nematodes (GIN) in lambs. In Experi...

Whole-farm phosphorus loss from grazing-based dairy farms

USDA-ARS?s Scientific Manuscript database

Phosphorus (P) loss from agricultural farms persists as a water quality impairment issue. For dairy farms, P can be lost from cropland, pastures, and open-air lots. We used interview surveys to document land use, cattle herd characteristics, and manure management for four grazing-based dairy farms i...

An experimental analysis of grasshopper community responses to fire and livestock grazing in a northern mixed-grass prairie

USDA-ARS?s Scientific Manuscript database

The outcomes of grasshopper responses to both vertebrate grazing and fire vary across grassland ecosystems, and are strongly influenced by local climactic factors. Thus, the possible application of grazing and fire as components of an ecologically-based grasshopper management strategy must necessari...

Butterfly responses to prairie restoration through fire and grazing

USGS Publications Warehouse

Vogel, Jennifer A.; Debinski, Diane M.; Koford, Rolf R.; Miller, J.R.

2007-01-01

The development of land for modern agriculture has resulted in losses of native prairie habitat. The small, isolated patches of prairie habitat that remain are threatened by fire suppression, overgrazing, and invasion by non-native species. We evaluated the effects of three restoration practices (grazing only, burning only, and burning and grazing) on the vegetation characteristics and butterfly communities of remnant prairies. Total butterfly abundance was highest on prairies that were managed with burning and grazing and lowest on those that were only burned. Butterfly species richness did not differ among any of the restoration practices. Butterfly species diversity was highest on sites that were only burned. Responses of individual butterfly species to restoration practices were highly variable. In the best predictive regression model, total butterfly abundance was negatively associated with the percent cover of bare ground and positively associated with the percent cover of forbs. Canonical correspondence analysis revealed that sites with burned only and grazed only practices could be separated based on their butterfly community composition. Butterfly communities in each of the three restoration practices are equally species rich but different practices yield compositionally different butterfly communities. Because of this variation in butterfly species responses to different restoration practices, there is no single practice that will benefit all species or even all species within habitat-specialist or habitat-generalist habitat guilds. ?? 2007 Elsevier Ltd. All rights reserved.

Pasture size effects on the ability of off-stream water or restricted stream access to alter the spatial/temporal distribution of grazing beef cows.

PubMed

Bisinger, J J; Russell, J R; Morrical, D G; Isenhart, T M

2014-08-01

For 2 grazing seasons, effects of pasture size, stream access, and off-stream water on cow distribution relative to a stream were evaluated in six 12.1-ha cool-season grass pastures. Two pasture sizes (small [4.0 ha] and large [12.1 ha]) with 3 management treatments (unrestricted stream access without off-stream water [U], unrestricted stream access with off-stream water [UW], and stream access restricted to a stabilized stream crossing [R]) were alternated between pasture sizes every 2 wk for 5 consecutive 4-wk intervals in each grazing season. Small and large pastures were stocked with 5 and 15 August-calving cows from mid May through mid October. At 10-min intervals, cow location was determined with Global Positioning System collars fitted on 2 to 3 cows in each pasture and identified when observed in the stream (0-10 m from the stream) or riparian (0-33 m from the stream) zones and ambient temperature was recorded with on-site weather stations. Over all intervals, cows were observed more (P ≤ 0.01) frequently in the stream and riparian zones of small than large pastures regardless of management treatment. Cows in R pastures had 24 and 8% less (P < 0.01) observations in the stream and riparian zones than U or UW pastures regardless of pasture size. Off-stream water had little effect on the presence of cows in or near pasture streams regardless of pasture size. In 2011, the probability of cow presence in the stream and riparian zones increased at greater (P < 0.04) rates as ambient temperature increased in U and UW pastures than in 2010. As ambient temperature increased, the probability of cow presence in the stream and riparian zones increased at greater (P < 0.01) rates in small than large pastures. Across pasture sizes, the probability of cow presence in the stream and riparian zone increased less (P < 0.01) with increasing ambient temperatures in R than U and UW pastures. Rates of increase in the probability of cow presence in shade (within 10 m of tree

Plant community responses to livestock grazing: An assessment of alternative management practices in a semiarid grassland

Treesearch

Matthew R. Loeser; Thomas D. Sisk; Timothy E. Crews

2001-01-01

One of the most prevalent land-use practices in the American Southwest, and one of the most contentious issues among land-use policymakers, is the grazing of domestic livestock. In an effort to contribute scientific understanding to this debate, we have designed experiments comparing the effects of alternative grazing regimes on plant communities. In a semiarid...

Effects of Grazing Regimes on Plant Traits and Soil Nutrients in an Alpine Steppe, Northern Tibetan Plateau

PubMed Central

Sun, Jian; Wang, Xiaodan; Cheng, Genwei; Wu, Jianbo; Hong, Jiangtao; Niu, Shuli

2014-01-01

Understanding the impact of grazing intensity on grassland production and soil fertility is of fundamental importance for grassland conservation and management. We thus compared three types of alpine steppe management by studying vegetation traits and soil properties in response to three levels of grazing pressure: permanent grazing (M1), seasonal grazing (M2), and grazing exclusion (M3) in the alpine steppe in Xainza County, Tibetan Plateau. The results showed that community biomass allocation did not support the isometric hypothesis under different grassland management types. Plants in M1 had less aboveground biomass but more belowground biomass in the top soil layer than those in M2 and M3, which was largely due to that root/shoot ratios of dominant plants in M1 were far greater than those in M2 and M3. The interramet distance and the tiller size of the dominant clonal plants were greater in M3 than in M1 and M2, while the resprouting from rhizome buds did not differ significantly among the three greezing regimes. Both soil bulk density and soil available nitrogen in M3 were greater than in M1 at the 15–30 cm soil depth (P = 0.05). Soil organic carbon and soil total nitrogen were greater in M3 than in M1 and M2 (P = 0.05). We conclude that the isometric hypothesis is not supported in this study and fencing is a helpful grassland management in terms of plant growth and soil nutrient retention in alpine steppe. The extreme cold, scarce precipitation and short growing period may be the causation of the unique plant and soil responses to different management regimes. PMID:25268517

Root traits predict decomposition across a landscape-scale grazing experiment

PubMed Central

Smith, Stuart W; Woodin, Sarah J; Pakeman, Robin J; Johnson, David; van der Wal, René

2014-01-01

Root litter is the dominant soil carbon and nutrient input in many ecosystems, yet few studies have considered how root decomposition is regulated at the landscape scale and how this is mediated by land-use management practices. Large herbivores can potentially influence below-ground decomposition through changes in soil microclimate (temperature and moisture) and changes in plant species composition (root traits). To investigate such herbivore-induced changes, we quantified annual root decomposition of upland grassland species in situ across a landscape-scale livestock grazing experiment, in a common-garden experiment and in laboratory microcosms evaluating the influence of key root traits on decomposition. Livestock grazing increased soil temperatures, but this did not affect root decomposition. Grazing had no effect on soil moisture, but wetter soils retarded root decomposition. Species-specific decomposition rates were similar across all grazing treatments, and species differences were maintained in the common-garden experiment, suggesting an overriding importance of litter type. Supporting this, in microcosms, roots with lower specific root area (m2 g−1) or those with higher phosphorus concentrations decomposed faster. Our results suggest that large herbivores alter below-ground carbon and nitrogen dynamics more through their effects on plant species composition and associated root traits than through effects on the soil microclimate. PMID:24841886

Concentrate Supplement Modifies the Feeding Behavior of Simmental Cows Grazing in Two High Mountain Pastures.

PubMed

Romanzin, Alberto; Corazzin, Mirco; Piasentier, Edi; Bovolenta, Stefano

2018-05-16

During grazing on Alpine pastures, the use of concentrates in dairy cows' diet leads to a reduction of the environmental sustainability of farms, and influences the selective pressure on some plant species. In order to minimize the use of concentrates, it is imperative to obtain data on the grazing behavior of cows. The aim of this study was to assess the effect of concentrate levels on the behavior of dairy cows during grazing. One hundred and ten lactating Italian Simmental cows, that sequentially grazed two pastures characterized by Poion alpinae (Poion) and Seslerion caeruleae (Seslerion) alliance, were considered. For each pasture, eight cows were selected and assigned to two groups: High and Low, supplemented with 4 kg/head/d, and 1 kg/head/d of concentrate respectively. Cows were equipped with a noseband pressure sensor and a pedometer (RumiWatch system, ITIN-HOCH GmbH) to assess grazing, ruminating, and walking behavior. In addition, the plant selection of the animals was assessed. On Poion, increased supplement intake caused a more intense selection of legumes, without affecting feeding and walking times. On Seslerion, grazing time was higher in Low than High. Grazing management in alpine region must take into account the great variability of pastures that largely differ from a floristic and nutritional point of view.

Effect of morning vs. afternoon grazing on intramuscular fatty acid composition in lamb.

PubMed

Vasta, Valentina; Pagano, Renato Italo; Luciano, Giuseppe; Scerra, Manuel; Caparra, Pasquale; Foti, Francesco; Cilione, Caterina; Biondi, Luisa; Priolo, Alessandro; Avondo, Marcella

2012-01-01

The aim of this study was to assess whether different grazing management affect animal performance and meat fatty acid composition. Thirty-five lambs were divided into three groups: 12 lambs grazed from 9 am to 5 pm (8 h group); 11 lambs grazed from 9 am to 1 pm (4hAM group) and 12 lambs grazed from 1 pm to 5 pm (4hPM group). The trial was conducted over 72 days. The 8 h lambs had greater DMI (P<0.0005) and final body weight (P<0.05) than the 4hPM and 4hAM lambs while carcass weight was not different between the three groups. The meat of the 4hPM lambs contained greater (P<0.05) percentages of polyunsaturated fatty acids, C18:2 cis-9 trans-11 and lower saturated fatty acids and C18:0 than the meat of the 8 h and 4hAM lambs. It is concluded that allowing lambs to graze during the afternoon rather than during 8 h does not compromise the carcass yield and results in a healthier meat fatty acid profile. Copyright © 2011 Elsevier Ltd. All rights reserved.

Assessment of native species and ungulate grazing in the Southwest: Terrestrial wildlife

Treesearch

Patrick W. Zwartjes; Jean-Luc E. Cartron; Pamela L. L. Stoleson; Walter C. Haussamen; Tiffany E Crane

2005-01-01

Range managers in the Southwestern States are increasingly being required to develop management strategies that take into consideration the conservation of wildlife populations. However, information on many aspects of the fundamental biology and impacts of grazing on individual species is still lacking in the scientific and government literature. This report documents...

Effects of past logging and grazing on understory plant communities in a montane Colorado forest

USGS Publications Warehouse

Fornwalt, P.J.; Kaufmann, M.R.; Huckaby, L.S.; Stohlgren, T.J.

2009-01-01

Throughout Pinus ponderosa-Pseudotsuga menziesii forests of the southern Colorado Front Range, USA, intense logging and domestic grazing began at the time of Euro-American settlement in the late 1800s and continued until the early 1900s. We investigated the long-term impacts of these settlement-era activities on understory plant communities by comparing understory composition at a historically logged and grazed site to that of an environmentally similar site which was protected from past use. We found that species richness and cover within functional groups rarely differed between sites in either upland or riparian areas. Multivariate analyses revealed little difference in species composition between sites on uplands, though compositional differences were apparent in riparian zones. Our findings suggest that settlement-era logging and grazing have had only minor long-term impacts on understories of upland Front Range P. ponderosa-P. menziesii forests, though they have had a greater long-term influence on riparian understories, where these activities were likely the most intense. ?? 2008 Springer Science+Business Media B.V.

Grazing Affects Exosomal Circulating MicroRNAs in Cattle

PubMed Central

Muroya, Susumu; Ogasawara, Hideki; Hojito, Masayuki

2015-01-01

Circulating microRNAs (c-miRNAs) are associated with physiological adaptation to acute and chronic aerobic exercise in humans. To investigate the potential effect of grazing movement on miRNA circulation in cattle, here we profiled miRNA expression in centrifugally prepared exosomes from the plasma of both grazing and housed Japanese Shorthorn cattle. Microarray analysis of the c-miRNAs resulted in detection of a total of 231 bovine exosomal miRNAs in the plasma, with a constant expression level of let-7g across the duration and cattle groups. Expression of muscle-specific miRNAs such as miR-1, miR-133a, miR-206, miR-208a/b, and miR-499 were undetectable, suggesting the mildness of grazing movement as exercise. According to validation by quantitative RT-PCR, the circulating miR-150 level in the grazing cattle normalized by the endogenous let-7g level was down-regulated after 2 and 4 months of grazing (P < 0.05), and then its levels in housed and grazing cattle equalized when the grazing cattle were returned to a housed situation. Likewise, the levels of miR-19b, miR-148a, miR-221, miR-223, miR-320a, miR-361, and miR-486 were temporarily lowered in the cattle at 1 and/or 2 month of grazing compared to those of the housed cattle (P < 0.05). In contrast, the miR-451 level was up-regulated in the grazing cattle at 2 months of grazing (P = 0.044). The elevation of miR-451 level in the plasma was coincident with that in the biceps femoris muscle of the grazing cattle (P = 0.008), which suggests the secretion or intake of miR-451 between skeletal muscle cells and circulation during grazing. These results revealed that exosomal c-miRNAs in cattle were affected by grazing, suggesting their usefulness as molecular grazing markers and functions in physiological adaptation of grazing cattle associated with endocytosis, focal adhesion, axon guidance, and a variety of intracellular signaling, as predicted by bioinformatic analysis. PMID:26308447

Cattle Grazing in Delta Forests

Treesearch

Robert L. Johnson

1960-01-01

What effects do grazing cattle have on the hardwood forests of the Mississippi Delta? What is the value of the forage to the cattle? To answer such questions, grazing studies were conducted in 1957 on the Delta Experimental Forest, near Stoneville.

43 CFR 4110.3 - Changes in grazing preference.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Changes in grazing preference. 4110.3... Qualifications and Preference § 4110.3 Changes in grazing preference. (a) The authorized officer will periodically review the grazing preference specified in a grazing permit or lease and make changes in the...

Prioritising coastal zone management issues through fuzzy cognitive mapping approach.

PubMed

Meliadou, Aleka; Santoro, Francesca; Nader, Manal R; Dagher, Manale Abou; Al Indary, Shadi; Salloum, Bachir Abi

2012-04-30

Effective public participation is an essential component of Integrated Coastal Zone Management implementation. To promote such participation, a shared understanding of stakeholders' objectives has to be built to ultimately result in common coastal management strategies. The application of quantitative and semi-quantitative methods involving tools such as Fuzzy Cognitive Mapping is presently proposed for reaching such understanding. In this paper we apply the Fuzzy Cognitive Mapping tool to elucidate the objectives and priorities of North Lebanon's coastal productive sectors, and to formalize their coastal zone perceptions and knowledge. Then, we investigate the potential of Fuzzy Cognitive Mapping as tool for support coastal zone management. Five round table discussions were organized; one for the municipalities of the area and one for each of the main coastal productive sectors (tourism, industry, fisheries, agriculture), where the participants drew cognitive maps depicting their views. The analysis of the cognitive maps showed a large number of factors perceived as affecting the current situation of the North Lebanon coastal zone that were classified into five major categories: governance, infrastructure, environment, intersectoral interactions and sectoral initiatives. Furthermore, common problems, expectations and management objectives for all sectors were exposed. Within this context, Fuzzy Cognitive Mapping proved to be an essential tool for revealing stakeholder knowledge and perception and understanding complex relationships. Copyright © 2011 Elsevier Ltd. All rights reserved.

Prehospital burn management in a combat zone.

PubMed

Lairet, Kimberly F; Lairet, Julio R; King, Booker T; Renz, Evan M; Blackbourne, Lorne H

2012-01-01

The purpose of this article is to provide a descriptive study of the management of burns in the prehospital setting of a combat zone. A retrospective chart review was performed of U.S. casualties with >20% total-body-surface-area thermal burns, transported from the site of injury to Ibn Sina Combat Support Hospital (CSH) between January 1, 2006, and August 30, 2009. Ibn Sina CSH received 225 burn casualties between January 2006 and August 2009. Of these, 48 met the inclusion criteria. The mean Injury Severity Score was 31.7 (range 4 to 75). Prehospital vascular access was obtained in 24 casualties (50%), and 20 of the casualties received fluid resuscitation. Out of the 48 casualties enrolled, 28 (58.3%) did not receive prehospital fluid resuscitation. Of the casualties who received fluid resuscitation, nearly all received volumes in excess of the guidelines established by the American Burn Association and those recommended by the Committee for Tactical Combat Casualty Care. With regard to pain management in the prehospital setting, 13 casualties (27.1%) received pain medication. With regard to the prehospital fluid resuscitation of primary thermal injury in the combat zone, two extremes were noted. The first group did not receive any fluid resuscitation; the second group was resuscitated with fluid volumes higher than those expected if established guidelines were utilized. Pain management was not uniformly provided to major burn casualties, even in several with vascular access. These observations support improved education of prehospital personnel serving in a combat zone.

Quantification of uncertainties in global grazing systems assessment

NASA Astrophysics Data System (ADS)

Fetzel, T.; Havlik, P.; Herrero, M.; Kaplan, J. O.; Kastner, T.; Kroisleitner, C.; Rolinski, S.; Searchinger, T.; Van Bodegom, P. M.; Wirsenius, S.; Erb, K.-H.

2017-07-01

Livestock systems play a key role in global sustainability challenges like food security and climate change, yet many unknowns and large uncertainties prevail. We present a systematic, spatially explicit assessment of uncertainties related to grazing intensity (GI), a key metric for assessing ecological impacts of grazing, by combining existing data sets on (a) grazing feed intake, (b) the spatial distribution of livestock, (c) the extent of grazing land, and (d) its net primary productivity (NPP). An analysis of the resulting 96 maps implies that on average 15% of the grazing land NPP is consumed by livestock. GI is low in most of the world's grazing lands, but hotspots of very high GI prevail in 1% of the total grazing area. The agreement between GI maps is good on one fifth of the world's grazing area, while on the remainder, it is low to very low. Largest uncertainties are found in global drylands and where grazing land bears trees (e.g., the Amazon basin or the Taiga belt). In some regions like India or Western Europe, massive uncertainties even result in GI > 100% estimates. Our sensitivity analysis indicates that the input data for NPP, animal distribution, and grazing area contribute about equally to the total variability in GI maps, while grazing feed intake is a less critical variable. We argue that a general improvement in quality of the available global level data sets is a precondition for improving the understanding of the role of livestock systems in the context of global environmental change or food security.

77 FR 62494 - Proposed Information Collection; Comment Request; Evaluations of Coastal Zone Management Act...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-15

... Collection; Comment Request; Evaluations of Coastal Zone Management Act Programs--State Coastal Management... request is for a new information collection. The Coastal Zone Management Act of 1972, as amended (CZMA; 16 U.S.C. 1451 et seq.) requires that state coastal management programs and national estuarine research...

Manatee grazing impacts on a mixed species seagrass bed

USGS Publications Warehouse

Lefebvre, Lynn W.; Provancha, Jane A.; Slone, Daniel H.; Kenworthy, W. Judson

2017-01-01

The endangered manatee Trichechus manatus is one of few large grazers in seagrass systems. To assess the long-term impacts of repeated grazing on seagrasses, we selected a study site within Kennedy Space Center in the northern Banana River, Brevard County, Florida, that was typically grazed by large numbers of manatees in spring. Two 13x13 m manatee exclosures and 2 paired open plots of equal size were established at the study site in October 1990. Shoot counts, biomass, and species composition of the co-dominant seagrass species, Syringodium filiforme and Halodule wrightii, were sampled 3 times per year in all 4 plots between October 1990 and October 1994. We used a Bayesian modelling approach, accounting for the influence of depth, to detect treatment (exclosed vs. open) effects. S. filiforme shoot counts, total biomass, and frequency of occurrence significantly increased in the exclosures. By July 1993, mean biomass values in the exclosures (167 g dry wt m-2) greatly exceeded those in the open plots (28 g dry wt m-2). H. wrightii decreased in the exclosures by 1994. Initially, both S. filiforme and H. wrightii responded positively to release from manatee grazing pressure. As S. filiforme continued to become denser in the exclosures, it gradually replaced H. wrightii. Our findings may be helpful to biologists and managers interested in predicting seagrass recovery and manatee carrying capacity of repeatedly grazed seagrass beds in areas of special significance to manatees and seagrass conservation.

Modelling Parasite Transmission in a Grazing System: The Importance of Host Behaviour and Immunity

PubMed Central

Fox, Naomi J.; Marion, Glenn; Davidson, Ross S.; White, Piran C. L.; Hutchings, Michael R.

2013-01-01

Parasitic helminths present one of the most pervasive challenges to grazing herbivores. Many macro-parasite transmission models focus on host physiological defence strategies, omitting more complex interactions between hosts and their environments. This work represents the first model that integrates both the behavioural and physiological elements of gastro-intestinal nematode transmission dynamics in a managed grazing system. A spatially explicit, individual-based, stochastic model is developed, that incorporates both the hosts’ immunological responses to parasitism, and key grazing behaviours including faecal avoidance. The results demonstrate that grazing behaviour affects both the timing and intensity of parasite outbreaks, through generating spatial heterogeneity in parasite risk and nutritional resources, and changing the timing of exposure to the parasites’ free-living stages. The influence of grazing behaviour varies with the host-parasite combination, dependent on the development times of different parasite species and variations in host immune response. Our outputs include the counterintuitive finding that under certain conditions perceived parasite avoidance behaviours (faecal avoidance) can increase parasite risk, for certain host-parasite combinations. Through incorporating the two-way interaction between infection dynamics and grazing behaviour, the potential benefits of parasite-induced anorexia are also demonstrated. Hosts with phenotypic plasticity in grazing behaviour, that make grazing decisions dependent on current parasite burden, can reduce infection with minimal loss of intake over the grazing season. This paper explores how both host behaviours and immunity influence macro-parasite transmission in a spatially and temporally heterogeneous environment. The magnitude and timing of parasite outbreaks is influenced by host immunity and behaviour, and the interactions between them; the incorporation of both regulatory processes is required to

Incorporating grazing into an eco-hydrologic model: Simulating coupled human and natural systems in rangelands

NASA Astrophysics Data System (ADS)

Reyes, J. J.; Liu, M.; Tague, C.; Choate, J. S.; Evans, R. D.; Johnson, K. A.; Adam, J. C.

2013-12-01

Rangelands provide an opportunity to investigate the coupled feedbacks between human activities and natural ecosystems. These areas comprise at least one-third of the Earth's surface and provide ecological support for birds, insects, wildlife and agricultural animals including grazing lands for livestock. Capturing the interactions among water, carbon, and nitrogen cycles within the context of regional scale patterns of climate and management is important to understand interactions, responses, and feedbacks between rangeland systems and humans, as well as provide relevant information to stakeholders and policymakers. The overarching objective of this research is to understand the full consequences, intended and unintended, of human activities and climate over time in rangelands by incorporating dynamics related to rangeland management into an eco-hydrologic model that also incorporates biogeochemical and soil processes. Here we evaluate our model over ungrazed and grazed sites for different rangeland ecosystems. The Regional Hydro-ecologic Simulation System (RHESSys) is a process-based, watershed-scale model that couples water with carbon and nitrogen cycles. Climate, soil, vegetation, and management effects within the watershed are represented in a nested landscape hierarchy to account for heterogeneity and the lateral movement of water and nutrients. We incorporated a daily time-series of plant biomass loss from rangeland to represent grazing. The TRY Plant Trait Database was used to parameterize genera of shrubs and grasses in different rangeland types, such as tallgrass prairie, Intermountain West cold desert, and shortgrass steppe. In addition, other model parameters captured the reallocation of carbon and nutrients after grass defoliation. Initial simulations were conducted at the Curlew Valley site in northern Utah, a former International Geosphere-Biosphere Programme Desert Biome site. We found that grasses were most sensitive to model parameters affecting

Nest sites of ducks in grazed mixed-grass prairie in North Dakota

USGS Publications Warehouse

Duebbert, H.F.; Lokemoen, J.T.; Sharp, D.E.

1986-01-01

Habitat use and nesting success of seven species of dabbling ducks were evaluated in five vegetative associations within grazed mixed-grass prairie in central North Dakota. During 1976-80, 548 nests were found on 412 ha of grazed prairie for an annual average density of 27 nests/100 ha. Numbers of nests found ranged from 1/100 ha in 1977 (a drought year) to 58/100 ha in 1979 (a very wet year), reflecting the variability that may be expected in a dynamic prairie wetland environment. Nesting success ranged from an average of 23% in the western snowberry (Symphoricarpos occidentalis) association to 34% in the mixed-grass association. Forty-two percent of the mallard (Anas platyrhynchos) nests and 35% of the gadwall (A. strepera) nests were in patches of western snowberry and/or Wood's rose (Rosa woodsii) that made up 2% of the available cover. Numbers of nests of blue-winged teal (A. discors) and northern shoveler (A. clypeata) were highest in cool-season grasses, especially green needlegrass (Stipa viridula) and western wheatgrass (Agropyron smithii). Height/density (HD) of residual cover decreased exponentially with increased grazing pressure. Use of grazed prairie by blue-winged teal was maximized when the HD of residual cover was 0.5 dm or higher, as could be maintained under light grazing. Results of this study indicated that properly grazed mixed-grass prairie can provide adequate nesting habitat for dabbling ducks. We recommend that preservation and sound ecological management be focused on large tracts of mixed-grass prairie with complexes of seasonal and semipermanent wetlands.

Reduced fine-scale spatial genetic structure in grazed populations of Dianthus carthusianorum

PubMed Central

Rico, Y; Wagner, H H

2016-01-01

Strong spatial genetic structure in plant populations can increase homozygosity, reducing genetic diversity and adaptive potential. The strength of spatial genetic structure largely depends on rates of seed dispersal and pollen flow. Seeds without dispersal adaptations are likely to be dispersed over short distances within the vicinity of the mother plant, resulting in spatial clustering of related genotypes (fine-scale spatial genetic structure, hereafter spatial genetic structure (SGS)). However, primary seed dispersal by zoochory can promote effective dispersal, increasing the mixing of seeds and influencing SGS within plant populations. In this study, we investigated the effects of seed dispersal by rotational sheep grazing on the strength of SGS and genetic diversity using 11 nuclear microsatellites for 49 populations of the calcareous grassland forb Dianthus carthusianorum. Populations connected by rotational sheep grazing showed significantly weaker SGS and higher genetic diversity than populations in ungrazed grasslands. Independent of grazing treatment, small populations showed significantly stronger SGS and lower genetic diversity than larger populations, likely due to genetic drift. A lack of significant differences in the strength of SGS and genetic diversity between populations that were recently colonized and pre-existing populations suggested that populations colonized after the reintroduction of rotational sheep grazing were likely founded by colonists from diverse source populations. We conclude that dispersal by rotational sheep grazing has the potential to considerably reduce SGS within D. carthusianorum populations. Our study highlights the effectiveness of landscape management by rotational sheep grazing to importantly reduce genetic structure at local scales within restored plant populations. PMID:27381322

Reduced fine-scale spatial genetic structure in grazed populations of Dianthus carthusianorum.

PubMed

Rico, Y; Wagner, H H

2016-11-01

Strong spatial genetic structure in plant populations can increase homozygosity, reducing genetic diversity and adaptive potential. The strength of spatial genetic structure largely depends on rates of seed dispersal and pollen flow. Seeds without dispersal adaptations are likely to be dispersed over short distances within the vicinity of the mother plant, resulting in spatial clustering of related genotypes (fine-scale spatial genetic structure, hereafter spatial genetic structure (SGS)). However, primary seed dispersal by zoochory can promote effective dispersal, increasing the mixing of seeds and influencing SGS within plant populations. In this study, we investigated the effects of seed dispersal by rotational sheep grazing on the strength of SGS and genetic diversity using 11 nuclear microsatellites for 49 populations of the calcareous grassland forb Dianthus carthusianorum. Populations connected by rotational sheep grazing showed significantly weaker SGS and higher genetic diversity than populations in ungrazed grasslands. Independent of grazing treatment, small populations showed significantly stronger SGS and lower genetic diversity than larger populations, likely due to genetic drift. A lack of significant differences in the strength of SGS and genetic diversity between populations that were recently colonized and pre-existing populations suggested that populations colonized after the reintroduction of rotational sheep grazing were likely founded by colonists from diverse source populations. We conclude that dispersal by rotational sheep grazing has the potential to considerably reduce SGS within D. carthusianorum populations. Our study highlights the effectiveness of landscape management by rotational sheep grazing to importantly reduce genetic structure at local scales within restored plant populations.

Grazing effects on soil characteristics and vegetation of grassland in northern China

NASA Astrophysics Data System (ADS)

Wang, Z.; Johnson, D. A.; Rong, Y.; Wang, K.

2016-01-01

Large areas of grassland in the agro-pastoral region of northern China were converted into cropland for grain production, and the remaining grasslands are being overgrazed and seriously degraded. The objective of this study was to evaluate how reductions in grazing intensity affect the soil and vegetation characteristics in grasslands of northern China. Soil heterogeneity and vegetation characteristics were evaluated for ungrazed (UG), moderate grazing (MG), and heavy grazing (HG) sites. Grazing increased diversity, but heavy grazing decreased aboveground biomass and increased the non-grass component. The non-grass proportion of total biomass increased with grazing intensity, which was 8, 16 and 48 % for UG, MG and HG sites, respectively. Species richness at the MG and HG sites was significantly higher than at the UG site (P< 0.05) with 3.6, 5.5 and 5.7 for UG, MG and HG sites, respectively. Strong spatial dependence of the examined soil properties at 10 m scale for all grazed sites was revealed by the ratio of nugget to total variation (0-23 %). Overgrazing homogenized soil characteristics at a 10 m scale. The ranges of spatial autocorrelation for soil organic C (SOC) and total N were both > 120 m at the HG site, which was considerably larger than that at the MG and UG sites with corresponding distances of 17.3 and 20.8 m for the MG site and 8.6 and 15.0 m for the UG site, respectively. The sampling density and sampling space for the HG site could be decreased under this scale sampling interval (10 m). Therefore, MG was recommended as the preferred management alternative for grasslands in northern China because of increased plant diversity without negative consequences related to decreased forage quality, forage quantity and soil heterogeneity for the investigated soil properties in northern China's grasslands.

Grazing alters net ecosystem C fluxes and the global warming potential of a subtropical pasture.

PubMed

Gomez-Casanovas, Nuria; DeLucia, Nicholas J; Bernacchi, Carl J; Boughton, Elizabeth H; Sparks, Jed P; Chamberlain, Samuel D; DeLucia, Evan H

2018-03-01

The impact of grazing on C fluxes from pastures in subtropical and tropical regions and on the environment is uncertain, although these systems account for a substantial portion of global C storage. We investigated how cattle grazing influences net ecosystem CO 2 and CH 4 exchange in subtropical pastures using the eddy covariance technique. Measurements were made over several wet-dry seasonal cycles in a grazed pasture, and in an adjacent pasture during the first three years of grazer exclusion. Grazing increased soil wetness but did not affect soil temperature. By removing aboveground biomass, grazing decreased ecosystem respiration (R eco ) and gross primary productivity (GPP). As the decrease in R eco was larger than the reduction in GPP, grazing consistently increased the net CO 2 sink strength of subtropical pastures (55, 219 and 187 more C/m 2 in 2013, 2014, and 2015). Enteric ruminant fermentation and increased soil wetness due to grazers, increased total net ecosystem CH 4 emissions in grazed relative to ungrazed pasture (27-80%). Unlike temperate, arid, and semiarid pastures, where differences in CH 4 emissions between grazed and ungrazed pastures are mainly driven by enteric ruminant fermentation, our results showed that the effect of grazing on soil CH 4 emissions can be greater than CH 4 produced by cattle. Thus, our results suggest that the interactions between grazers and soil hydrology affecting soil CH 4 emissions play an important role in determining the environmental impacts of this management practice in a subtropical pasture. Although grazing increased total net ecosystem CH 4 emissions and removed aboveground biomass, it increased the net storage of C and decreased the global warming potential associated with C fluxes of pasture by increasing its net CO 2 sink strength. © 2017 by the Ecological Society of America.

Coastal zone - Terra (and aqua) incognita - Integrated Coastal Zone Management in the Black Sea

NASA Astrophysics Data System (ADS)

Kosyan, R. D.; Velikova, V. N.

2016-02-01

In the Black Sea coastal states (Bulgaria, Georgia, Romania, Russian Federation, Turkey, and Ukraine), Integrated Coastal Zone Management (ICZM) has no properly established legal and institutional framework. The term "coastal zone" is undefined in national (reportedly with the exception of Bulgaria) and regional legislative documents. The interface between science and policy within ICZM remains poorly developed. Policies for streamlining efforts have been ill-managed and decisions taken in functional zoning and the balanced use and protection of coastal zones have often been shown to be incorrect. The observed proliferation of consultative committees and councils has not been much helpful, public participation has been widely neglected. Illegal practices are in place, and coastal developments continue being largely unsustainable. These problems are often explained by the low awareness of ICZM benefits, and hence, a shortage of political good will, but also by the lack of appropriate Black Sea scientific research, which would ensure a fundamental knowledge-base. There are hundreds of organizations involved in collection of data and information of relevance for ICZM, although there is a distinct lack of coordination. Consequently, there is a substantial overlap of activities, whilst important scientific and policy questions remain unanswered. We review the status of ICZM or mismanagement (ICZmisM) in the Black Sea region, building links between environmental problems and policy measures in response, and providing appropriate examples. Recommendations are put forward with regard to major gaps in ICZM at levels of its theoretical development and practical implementation within the region. The review is intended to remind of major disastrous consequences of present complacency and laissez-faire in the management of the Black Sea. This paper calls for urgent implementation of ICZM in the Black Sea at national and regional levels.

Nitrous oxide production and consumption by denitrification in a grassland: Effects of grazing and hydrology.

PubMed

Hu, Jing; Inglett, Kanika S; Clark, Mark W; Inglett, Patrick W; Ramesh Reddy, K

2015-11-01

Denitrification is generally recognized as a major mechanism contributing to nitrous oxide (N2O) production, and is the only known biological process for N2O consumption. Understanding factors controlling N2O production and consumption during denitrification will provide insights into N2O emission variability, and potentially predict capacity of soils to serve as sinks or sources of N2O. This study investigated the effects of hydrology and grazing on N2O production and consumption in a grassland based agricultural watershed. A batch incubation study was conducted on soils (0-10 cm) collected along a hydrological gradient representing isolated wetland (Center), transient zone (Edge) and pasture upland (Upland), from both grazed and ungrazed areas. Production and consumption potentials of N2O were quantified on soils under four treatments, including (i) ambient condition, and amended with (ii) NO3(-), (iii) glucose-C, and (iv) NO3(-) +glucose-C. The impacts of grazing on N2O production and consumption were not observed. Soils in hydrologically distinct zones responded differently to N2O production and consumption. Under ambient conditions, both production and consumption rates of Edge soils were higher than those observed for Center and Upland soils. Results of amended incubations suggested NO3(-) was a key factor limiting N2O production and consumption rates in all hydrological zones. Over 5-d incubation with NO3(-) amendment, cumulative production and consumption of N2O for Center soils were 1.6 and 3.3 times higher than Edge soils, and 3.6 and 7.6 times higher than Upland soils, respectively. However, cumulative N2O net production for Edge soils was the highest, with 2 to 3 times higher than Upland and Center soils. Our results suggest that the transient areas between wetland and upland are likely to be "hot spots" of N2O emissions in this ecosystem. Wetlands within agricultural landscapes can potentially function to reduce both NO3(-) leaching and N2O emissions

Grazing history effects on rangeland biomass, cover and diversity responses to fire and grazing utilization

USDA-ARS?s Scientific Manuscript database

Exclusion of large grazers from rangelands that evolved with significant grazing pressure can alter natural processes and may have legacy effects by changing magnitude or direction of community responses to subsequent disturbance. Three moderately grazed pastures were paired with 12-ha areas that h...

Grazed grass was estimated via satellite images better then mowed grass

NASA Astrophysics Data System (ADS)

Koncz, Péter; Gubányi, András; Gecse, Bernadett; Tolnai, Márton; Pintér, Krisztina; Kertész, Péter; Fóti, Szilvia; Balogh, János; Nagy, Zoltán

2017-04-01

Precise livestock management requires objective alert system about the potential threats of overgrazing and intensive mowing. This kind of system could be based on the estimation of the amount of grazed and mowed biomass by remote sensing of vegetation indices. In our study we used the Normalized Difference Vegetation Index (NDVI) derived from Landsat 7 and 8 satellites to establish a regression between the vegetation index and the biomass (cut from ten, 40× 40 cm plots, during 52 measurement campaigns, 2011-2013) in a semi-arid grassland of Hungary, Bugac. Based on the regression time series of NDVI data were converted into biomass data in case of grazed and mowed areas (2011?2016). Biomass changes, inferred from NDVI data, were compared to the estimated grazed (based on daily dry matter uptake of cattle) and measured mowed (weighted) biomass. We found significant correlation between the NDVI and the total biomass (r2=0.6, p<0.05, n=52, RMSE=52.8 g m-2) and a stronger one between the NDVI and the green biomass (r2=0.75, p<0.05, n=52, RMSE=36.8 g m-2). We found that the amount of grazed biomass based on dry matter uptake was in close agreement with the biomass changes inferred from NDVI data (r2=0.42, p=0.11, n=7, RMSE=25.2 g m-2). However, there was no correlation between the biomass of the measured hay and the biomass inferred from NDVI data (r2=0.16, p=0.49, n=5, RMSE=67.4 g m-2). This was most probably due to the fact that mowing is a sudden, while grazing is a prolonged event, hence satellite data are less likely to be available before and after the mowing events (i.e. within days) compared to the grazing periods which usually lasts for months (only 12±2 satellite images were suitable per year). Therefore, NDVI changes are more accurately captured when grazing is observed than when mowing. We concluded that NDVI data from satellite images could be used to estimate the amount of grazed biomass, however to estimate the amount of mowed hay more frequent data

Riparian-fisheries habitat responses to late spring cattle grazing

Treesearch

Warren P. Clary; John W. Kinney

2000-01-01

A grazing study was conducted on a cold, mountain meadow riparian system in central Idaho in response to cattle grazing-salmonid fisheries conflicts. Six pastures were established along a 3rd order, 2 to 3 m wide stream to study the effects on fisheries habitat of no grazing, light grazing (20 to 25% use), and medium grazing (35 to 50%) during late June. Most...

15 CFR Appendix F to Subpart M of... - Davidson Seamount Management Zone

Code of Federal Regulations, 2011 CFR

2011-01-01

... 15 Commerce and Foreign Trade 3 2011-01-01 2011-01-01 false Davidson Seamount Management Zone F Appendix F to Subpart M of Part 922 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign... Sanctuary Pt. 922, Subpt. M, App. F Appendix F to Subpart M of Part 922—Davidson Seamount Management Zone...

Characterization and typification of small ruminant farms providing fuelbreak grazing services for wildfire prevention in Andalusia (Spain).

PubMed

Mena, Y; Ruiz-Mirazo, J; Ruiz, F A; Castel, J M

2016-02-15

Several wildfire prevention programs in Spain are using grazing livestock to maintain fuelbreaks with low levels of biomass. Even though shepherds are remunerated for these services, many of their farms are hardly viable in the current socio-economic context. By analyzing 54 small ruminant farms participating in the Grazed Fuelbreak Network in Andalusia (southern Spain), this research aimed to identify the main types and characteristics of such farms and, considering the challenges they are facing, propose strategies to improve both their economic viability and their effectiveness in fuelbreak grazing. Based on data collected through a survey on key farm management aspects, a multivariate analysis was performed and four main types of farm were identified: two clusters of dairy goat farms and two composed mostly of meat-purpose sheep farms. Farms in all clusters could benefit from improvements in the feeding and reproductive management of livestock, either to enhance their productivity or to make better use of the pasture resources available. Dairy goat farms remain more dependent on external animal feed to ensure a better lactation, therefore they should either diminish their workforce costs per animal or sell transformed products directly to consumers to improve their economic viability. Best fuelbreak grazing results were related to larger flocks combining sheep and goats, lower ratios of fuelbreak surface area per animal, and longer (year-long) grazing periods on fuelbreaks. Therefore, such farm features and adjusted fuelbreak assignments should be favored in wildfire prevention programs using grazing services. Copyright © 2015 Elsevier B.V. All rights reserved.

Precision control of soil N cycling via soil functional zone management

USDA-ARS?s Scientific Manuscript database

Managing the soil nitrogen (N) cycle is a major component of agricultural sustainability. Soil functional zone management (SFZM), a novel framework of agroecosystem management, may improve soil N management compared with conventional and no-tillage approaches by focusing on the timing and location (...

Meta-analysis of the effect of pregrazing pasture mass on pasture intake, milk production, and grazing behavior of dairy cows strip-grazing temperate grasslands.

PubMed

Pérez-Prieto, L A; Delagarde, R

2012-09-01

Grazing management is a key factor in pasture-based dairy systems, which can be improved given advanced knowledge of the effects of pregrazing pasture mass (PM) on the performance of dairy cows. The aim of this study was to quantify the effects of PM on the pasture intake, milk production, milk composition, and grazing behavior of strip- or rotational-grazing dairy cows, based on a meta-analysis of published research papers. A database was created that included experiments in which the effects of PM on pasture intake and milk production of dairy cows were studied. Papers were selected only if at least 2 PM were compared under similar experimental conditions, particularly the same pasture allowance (SPA). The final database included 15 papers with 27 PM comparisons. For analytical purposes, the database was subdivided into 3 subsets that varied according to the estimation height at which pasture allowance was determined; that is, where PM were compared at the SPA above ground level (SPA(0) subset), above 2 to 3 cm (SPA(3) subset), and above 4 to 5 cm (SPA(5) subset). Statistical analyses were conducted on the entire database (global analysis) and within each subset using linear model procedures. An interaction between PM and estimation height was found for pasture intake and milk production in the global analysis. On the basis of the predictive equations, pasture intake increased by 1.58 kg of dry matter/d per tonne increase in PM when PM were compared at SPA(0), was not affected by PM when PM were compared at SPA(3), and decreased by 0.65 kg of dry matter/d per tonne increase in PM when PM were compared at SPA(5). This is consistent with the effect of PM on milk production, which was positive and negative (1.04 and -0.79 kg/t of PM, respectively) when PM were compared at SPA(0) and SPA(5), respectively. Grazing time was only slightly affected by PM, irrespective of estimation height, because the effect of PM on pasture intake was mainly dependent on the variation

78 FR 48046 - Safety Zone; Kuoni Destination Management Fireworks; San Diego, CA

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-07

...-AA00 Safety Zone; Kuoni Destination Management Fireworks; San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a safety zone on the navigable..., 2013. This temporary safety zone is necessary to provide for the safety of the participants, crew...

Comparing the Relative Importance of Water-Borne Cues and Direct Grazing for the Induction of Defenses in the Brown Seaweed Fucus vesiculosus

PubMed Central

Flöthe, Carla R.; John, Uwe; Molis, Markus

2014-01-01

Some seaweed species have been shown to release water-borne cues after herbivore attack, for example, to attract natural enemies of the herbivore. These cues may also be sensed by neighboring seaweeds and used to adjust their defenses in anticipation of a possible herbivore attack. Several studies indicated information transfer between seaweed individuals in the past, including the brown seaweed Fucus vesiculosus. Previous work showed induction of defenses in F. vesiculosus in response to water-borne cues released by isopod-grazed conspecifics. In contrast, another study on induced responses after exposure to cues from isopod-grazed neighbors using the same seaweed species yielded contradictory results. This study reassessed the ability of F. vesiculosus individuals to sense water-borne cues released by isopod-grazed neighbors in a series of experiments that monitored F. vesiculosus palatability in response to direct grazing by Idotea baltica and water-borne cues from isopod-grazed neighbors relative to unmanipulated seaweed pieces. Two-choice feeding assays were conducted with both fresh and reconstituted seaweed pieces. Direct grazing by I. baltica induced a chemical defense in F. vesiculosus, confirming results of previous studies. In contrast, evidence for increased herbivore resistance in seaweed pieces that were located downstream of isopod-grazed F. vesiculosus could not be provided. The lack of defense induction in response to grazing of conspecific neighbors may be explained by the environmental conditions and the scattered distribution of F. vesiculosus individuals in the intertidal zone of Helgoland, which may render resource investment in the emission and/or response to water-borne cues at this site unprofitable. PMID:25279662

Assessing the opportunity cost of implementing streamside management zone guidelines in eastern hardwood forests

Treesearch

Chris B. LeDoux

2006-01-01

Forest landowners, managers, loggers, land-use planners, and other decision/policy makers need to understand the opportunity cost associated with different levels of allowable management and required/voluntary protection in streamside management zones (SMZs). Four different logging technologies, two mature hardwood stands, three levels of streamside zone protection,...

The Influence of Climate, Soil and Pasture Type on Productivity and Greenhouse Gas Emissions Intensity of Modeled Beef Cow-Calf Grazing Systems in Southern Australia

PubMed Central

Bell, Matthew J.; Cullen, Brendan R.; Eckard, Richard J.

2012-01-01

Simple Summary Livestock production systems and the agricultural industries in general face challenges to meet the global demand for food, whilst also minimizing their environmental impact through the production of greenhouse gas (GHG) emissions. Livestock grazing systems in southern Australia are low input and reliant on pasture as a low-cost source of feed. The balance between productivity and GHG emission intensity of beef cow-calf grazing systems was studied at sites chosen to represent a range of climatic zones, soil and pasture types. While the climatic and edaphic characteristics of a location may impact on the emissions from a grazing system, management to efficiently use pasture can reduce emissions per unit product. Abstract A biophysical whole farm system model was used to simulate the interaction between the historical climate, soil and pasture type at sites in southern Australia and assess the balance between productivity and greenhouse gas emissions (expressed in carbon dioxide equivalents, CO2-eq.) intensity of beef cow-calf grazing systems. Four sites were chosen to represent a range of climatic zones, soil and pasture types. Poorer feed quality and supply limited the annual carrying capacity of the kikuyu pasture compared to phalaris pastures, with an average long-term carrying capacity across sites estimated to be 0.6 to 0.9 cows/ha. A relative reduction in level of feed intake to productivity of calf live weight/ha at weaning by feeding supplementary feed reduced the average CO2-eq. emissions/kg calf live weight at weaning of cows on the kikuyu pasture (18.4 and 18.9 kg/kg with and without supplementation, respectively), whereas at the other sites studied an increase in intake level to productivity and emission intensity was seen (between 10.4 to 12.5 kg/kg without and with supplementary feed, respectively). Enteric fermentationand nitrous oxide emissions from denitrification were the main sources of annual variability in emissions intensity

Allelopathic cover crop prior to seeding is more important than subsequent grazing/mowing in grassland establishment

USGS Publications Warehouse

Milchunas, Daniel G.; Vandever, Mark W.; Ball, Leonard O.; Hyberg, Skip

2011-01-01

The effects of grazing, mowing, and type of cover crop were evaluated in a previous winter wheat–fallow cropland seeded to grassland under the Conservation Reserve Program in eastern Colorado. Prior to seeding, the fallow strips were planted to forage sorghum or wheat in alternating strips (cover crops), with no grazing, moderate to heavy grazing, and mowing (grazing treatments) superimposed 4 yr after planting and studied for 3 yr. Plots previously in wheat had more annual and exotic species than sorghum plots. Concomitantly, there were much greater abundances of perennial native grass and all native species in sorghum than wheat cropped areas. The competitive advantage gained by seeded species in sorghum plots resulted in large increases in rhizomatous western wheatgrass. Sorghum is known to be allelopathic and is used in crop agriculture rotations to suppress weeds and increase crop yields, consistent with the responses of weed and desired native species in this study. Grazing treatment had relatively minor effects on basal and canopy cover composition of annual or exotic species versus perennial native grass or native species. Although grazing treatment never was a significant main effect, it occasionally modified cover crop or year effects. Opportunistic grazing reduced exotic cheatgrass by year 3 but also decreased the native palatable western wheatgrass. Mowing was a less effective weed control practice than grazing. Vegetative basal cover and aboveground primary production varied primarily with year. Common management practices for revegetation/restoration currently use herbicides and mowing as weed control practices and restrict grazing in all stages of development. Results suggest that allelopathic cover crop selection and opportunistic grazing can be effective alternative grass establishment and weed control practices. Susceptibility, resistance, and interactions of weed and seeded species to allelopathic cover species/cultivars may be a fruitful area

Simulating runoff from small grazed pasture watersheds located at North Appalachian Experimental Watershed in Ohio

USDA-ARS?s Scientific Manuscript database

Runoff from grazing pasture lands can impact water quality in receiving streams if not well managed. Management consists of conservation practices to reduce runoff and pollutants transport. Simulation models have been effectively used to design and implement these conservation practices. The Agricul...

Small mammal communities of streamside management zones in intensively managed pine forests of Arkansas

Treesearch

Darren A. Miller; Ronald E. Thill; M. Anthony Melchiors; T. Bently Wigley; Philip A. Tappe

2004-01-01

Streamside management zones (SMZs), composed primarily of hardwoods in the southeastern United States, provide habitat diversity within intensively managed pine (Pinus spp.) plantations. However, effects of SMZ width and adjacent plantation structure on riparian wildlife communities are poorly understood. Therefore, during 1990-1995, we examined small mammal...

76 FR 77769 - North Finger Grazing Authorization Project, Malheur National Forest, Grant County, OR

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-14

... allotments within the North Finger Landscape. These allotments are within the Upper Deer Creek, Basin Creek... is to authorize grazing on all or portions of the North Finger landscape in such a manner that will... incorporating adaptive management strategies across the North Finger landscape. Adaptive Management is defined...

A Systematic Review of Wild Burro Grazing Effects on Mojave Desert Vegetation, USA

NASA Astrophysics Data System (ADS)

Abella, Scott R.

2008-06-01

Wild burros ( Equus asinus), protected by the 1971 Wild Free-Roaming Horse and Burro Act on some federal lands but exotic animals many ecologists and resource mangers view as damaging to native ecosystems, represent one of the most contentious environmental management problems in American Southwest arid lands. This review synthesizes the scattered literature about burro effects on plant communities of the Mojave Desert, a center of burro management contentions. I classified 24 documents meeting selection criteria for this review into five categories of research: (i) diet analyses directly determining which plant species burros consume, (ii) utilization studies of individual species, (iii) control-impact comparisons, (iv) exclosure studies, and (v) forage analyses examining chemical characteristics of forage plants. Ten diet studies recorded 175 total species that burros consumed. However, these studies and two exclosure studies suggested that burros preferentially eat graminoid and forb groups over shrubs. One study in Death Valley National Park, for example, found that Achnatherum hymenoides (Indian ricegrass) was 11 times more abundant in burro diets than expected based on its availability. Utilization studies revealed that burros also exhibit preferences within the shrub group. Eighty-three percent of reviewed documents were produced in a 12-year period, from 1972 to 1983, with the most recent document produced in 1988. Because burros remain abundant on many federal lands and grazing may interact with other management concerns (e.g., desert wildfires fueled by exotic grasses), rejuvenating grazing research to better understand both past and present burro effects could help guide revegetation and grazing management scenarios.

A systematic review of wild burro grazing effects on Mojave Desert vegetation, USA.

PubMed

Abella, Scott R

2008-06-01

Wild burros (Equus asinus), protected by the 1971 Wild Free-Roaming Horse and Burro Act on some federal lands but exotic animals many ecologists and resource mangers view as damaging to native ecosystems, represent one of the most contentious environmental management problems in American Southwest arid lands. This review synthesizes the scattered literature about burro effects on plant communities of the Mojave Desert, a center of burro management contentions. I classified 24 documents meeting selection criteria for this review into five categories of research: (i) diet analyses directly determining which plant species burros consume, (ii) utilization studies of individual species, (iii) control-impact comparisons, (iv) exclosure studies, and (v) forage analyses examining chemical characteristics of forage plants. Ten diet studies recorded 175 total species that burros consumed. However, these studies and two exclosure studies suggested that burros preferentially eat graminoid and forb groups over shrubs. One study in Death Valley National Park, for example, found that Achnatherum hymenoides (Indian ricegrass) was 11 times more abundant in burro diets than expected based on its availability. Utilization studies revealed that burros also exhibit preferences within the shrub group. Eighty-three percent of reviewed documents were produced in a 12-year period, from 1972 to 1983, with the most recent document produced in 1988. Because burros remain abundant on many federal lands and grazing may interact with other management concerns (e.g., desert wildfires fueled by exotic grasses), rejuvenating grazing research to better understand both past and present burro effects could help guide revegetation and grazing management scenarios.

The role of grazing land on the buffalo population dynamics in Brebes regency

NASA Astrophysics Data System (ADS)

Sumanto

2017-04-01

Brebes District is one of the centre of grazing buffalo in Indonesia that involve thousands of rearers usually kept as a family savings. This paper highlighted the availability of land and the role of the grazing land for the durability of the maintenance of buffalo in Brebes Regency. The information obtained is from interviewed the livestock facilitators in the sub-district (primary data) and from statistic of agriculture in Brebes Regency 2014 (secondary data). Generally the buffalo kept semi-intensively and commonly the buffaloes graze in the fields that are not used from morning until evening and during nights buffaloes are placed in the stalls. Rearers chose the semi-intensive system in rearing the buffalo because it is considered easy to manage and they do not need to provide fresh money to prepare the roughage for feed, because commonly the grazing buffalo are shepherd by herdman that will receive buffalo as their payment. The population density is very high (1.056 heads/km2), the buffalo ownership is between 2-4 head/households; generally the location of the grazing land is in the forest, rice fields fallow, and sleeping land, and estimated that greenfeed stock is still available abunandtly, on the other hand the urban land is less capacity of feed. The spread of buffalo is only in 125 villages from 297 villages in Brebes. The acceptance of buffalo business is around IDR 3.5 million to IDR 7.5 million/family/year. The availability of grazing land strongly influence the maintaining of buffalo farming by rearers.

Response of mountain meadows to grazing by recreational pack stock

Treesearch

David N. Cole; Jan W. van Wagtendonk; Mitchel P. McClaran; Peggy E. Moore; Neil K. McDougald

2004-01-01

Effects of recreational pack stock grazing on mountain meadows in Yosemite National Park were assessed in a 5-year study. Yosemite is a designated wilderness, to be managed such that its natural conditions are preserved. Studies were conducted in 3 characteristic meadow types: shorthair sedge (Carex filifolia Nutt.), Brewer’s reed grass (...

50 CFR 648.148 - Special management zones.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Black Sea Bass Fishery § 648.148 Special management zones. The recipient of a U.S. Army Corps of... purposes of fishing may request that an area surrounding and including the site be designated by the MAFMC... fishing gear that are not compatible with the intent of the artificial reef or fish attraction device or...

Effects of Grazing Management and Cattle on Aquatic Habitat Use by the Anuran Pseudopaludicola mystacalis in Agro-Savannah Landscapes

PubMed Central

Garey, Michel V.; Rossa-Feres, Denise C.

2016-01-01

Because of their strong dependence on the environment, the spatial distribution of pond-breeding amphibians can be greatly influenced by anthropogenic habitat alteration. In some agricultural landscapes in Brazil, the anuran Pseudopaludicola mystacalis appears to be highly influenced by land use. Because adult males and tadpoles of this species are usually found in marshy areas with cattle hoof prints, we hypothesized that P. mystacalis preferentially occupies aquatic habitats with marshy areas that are trampled by cattle. To test our hypothesis, we assessed whether the occurrence of P. mystacalis is associated with the presence of cattle and trampled marshy areas, and which environmental features best explain the spatial distribution and abundance of P. mystacalis. To do so, we sampled 38 aquatic habitats in an area intensely used for livestock in southeastern Brazil. We found that the presence of cattle and trampled marshy areas in aquatic habitats are positively associated to P. mystacalis occurrence. Additionally, the abundance of calling males is better predicted by variables of landscape and local habitat structure. Specifically, the size of trampled marshy areas and the proportion of herbaceous vegetation within the aquatic habitat are positively associated with abundance, while distance to nearest aquatic habitat are negatively associated with abundance of calling males. All three of these variables can be directly or indirectly linked to the presence of cattle or grazing management. Therefore, this work shows evidence that Pseudopaludicola mystacalis is positively influenced by grazing management with cattle, and draws attention to other unknown potential consequences of different land use to fresh water diversity. PMID:27658203

Fire and grazing regulate belowground processes in tallgrass prairie

USGS Publications Warehouse

Johnson, Loretta C.; Matchett, John R.

2001-01-01

In tallgrass prairie, belowground processes are even more important than in forested systems because aboveground biomass and standing dead litter are periodically removed by frequent fires or grazers. Thus, studies that address factors regulating belowground processes are especially relevant for tallgrass prairie. We predicted that effects of grazing and burning differ belowground and that changes in root productivity caused by burning or grazing provide feedback that affects ecosystem fluxes of C and N. These differences in belowground response should be driven largely by changes in N dynamics and the degree to which burning and grazing affect the pathway and magnitude of N loss and the degree of N limitation in these systems. Fire, the major pathway of N loss in ungrazed tallgrass prairie, should result in reduced net N mineralization and N availability. We expected plants to compensate for increased N limitation by increasing their allocation to roots, as manifested in increased soil respiration and C cycling belowground. In contrast, grazing conserves N in the ecosystem by redistributing the N once contained in grass to labile forms in urine and dung. Thus, we predicted that grazing should increase N cycling rates and N availability to plants. Consequently, grazed plants should be less N limited and should allocate less C to roots and more to shoots. This, in turn, should decrease belowground C cycling, manifested as reduced soil CO2 flux.We explored the roles of grazing and burning on root growth in experimental watersheds at Konza Prairie, Kansas, USA. To assess effects of fire on root productivity, we installed root ingrowth cores in two watersheds without grazers that differ in fire frequency: annually vs. infrequently burned (four years since the last fire). To assess effects of grazing, we installed root ingrowth cores in an annually burned watershed grazed by bison and in fenced controls (exclosures). Within bison “grazing lawns,” root ingrowth cores

Effect of continuous v. daytime grazing on feed intake and growth of sheep grazing in a semi-arid grassland steppe.

PubMed

Müller, K; Lin, L; Wang, C; Glindemann, T; Schiborra, A; Schönbach, P; Wan, H; Dickhoefer, U; Susenbeth, A

2012-03-01

In the Inner Mongolian steppe, China, sheep generally graze during daytime and are kept in yards overnight. Hence, nutrients are not returned to the grassland, which might reduce its long-term productivity. Furthermore, the restricted grazing time may limit forage intake and thus the performance of sheep. The aim of this study was therefore to evaluate the impact of continuous 24-h grazing (CG) v. the common daytime grazing (DG) on herbage mass (HM), feed quality, feed organic matter intake (OMI) and live weight gain (LWG) of sheep in the Inner Mongolian steppe. Experiments were carried out from July to September, between 2005 and 2007 on two 2-ha plots per grazing treatment. Each month, the external faecal marker titanium dioxide (TiO(2)) was orally administered to six sheep per plot on 10 consecutive days. Faecal grab samples were obtained from day 6 to 10 and analysed for CP concentrations to estimate digestibility of organic matter (dOM). Faecal TiO(2) concentrations were used to determine the total faecal output and hence OMI of sheep. Concomitant to faeces collection, HM and quality, as well as LWG of the animals were measured. HM and herbage quality did not differ between treatments. However, as the season progressed, concentrations of NDF, ADF and ADL increased, whereas HM and CP concentrations declined. HM and herbage quality parameters differed between years according to the annual precipitation. dOM was similar in CG (0.577) and DG (0.572) sheep, but it decreased from July (0.583) to September (0.558) and differed between years. Accordingly, the OMI of sheep was similar for both treatments across the entire grazing season and all study years. Although mean LWG differed between months and years, it was identical in CG (101.5 g/day) and DG sheep (101.8 g/day). Additional time on pasture during night does not increase feed intake or animal performance. Positive effects of a nutrient reflux on grassland productivity and herbage quality when animals remained

Effects of Grazing and Fire Frequency on Floristic Quality and its Relationship to Indicators of Soil Quality in Tallgrass Prairie

NASA Astrophysics Data System (ADS)

Manning, George C.; Baer, Sara G.; Blair, John M.

2017-12-01

Fire and grazing are widely used to manage grasslands for conservation purposes, but few studies have evaluated the effects of these drivers on the conservation value of plant communities measured by the floristic quality index (FQI). Further, the influence of fire and grazing on soil properties and functions are difficult for land managers and restoration practitioners to assess. The objectives of this study were to: (1) quantify the independent and interactive effects of grazing and fire frequency on floristic quality in native tallgrass prairie to provide potential benchmarks for community assessment, and (2) to explore whether floristic quality can serve as an indicator of soil structure and function for more holistic ecosystem assessments. A factorial combination of fire frequencies (1-2, 4, and 20 years return intervals) and grazing (by bison or ungrazed) treatments were sampled for plant species composition, and for several indicators of soil quality in lowland tallgrass prairie. Floristic quality, diversity, and richness were higher in grazed than ungrazed prairie over all fire frequencies ( P < 0.05). Available inorganic N, microbial biomass N, total N, and soil bulk density were also higher in grazed prairie soil over all fire frequencies ( P < 0.05). Microbial biomass C, total organic C, and total soil N were positively correlated with FQI ( P < 0.05). This study shows that floristic quality and soil N pools are more strongly influenced by grazing than fire and that floristic quality can be an indicator of total soil C and N stocks in never cultivated lowland prairie.

Effects of Grazing and Fire Frequency on Floristic Quality and its Relationship to Indicators of Soil Quality in Tallgrass Prairie.

PubMed

Manning, George C; Baer, Sara G; Blair, John M

2017-12-01

Fire and grazing are widely used to manage grasslands for conservation purposes, but few studies have evaluated the effects of these drivers on the conservation value of plant communities measured by the floristic quality index (FQI). Further, the influence of fire and grazing on soil properties and functions are difficult for land managers and restoration practitioners to assess. The objectives of this study were to: (1) quantify the independent and interactive effects of grazing and fire frequency on floristic quality in native tallgrass prairie to provide potential benchmarks for community assessment, and (2) to explore whether floristic quality can serve as an indicator of soil structure and function for more holistic ecosystem assessments. A factorial combination of fire frequencies (1-2, 4, and 20 years return intervals) and grazing (by bison or ungrazed) treatments were sampled for plant species composition, and for several indicators of soil quality in lowland tallgrass prairie. Floristic quality, diversity, and richness were higher in grazed than ungrazed prairie over all fire frequencies (P < 0.05). Available inorganic N, microbial biomass N, total N, and soil bulk density were also higher in grazed prairie soil over all fire frequencies (P < 0.05). Microbial biomass C, total organic C, and total soil N were positively correlated with FQI (P < 0.05). This study shows that floristic quality and soil N pools are more strongly influenced by grazing than fire and that floristic quality can be an indicator of total soil C and N stocks in never cultivated lowland prairie.

Effects of anthropogenic fragmentation and livestock grazing on western riparian bird communities

USGS Publications Warehouse

Tewksbury, J.J.; Black, A.E.; Nur, N.; Saab, V.A.; Logan, B.D.; Dobkin, D.S.

2002-01-01

(Turdus migratorius), Brown-headed Cowbird (Molothrus ater), and Black-billed Magpie (Pica pica), all species that use both agricultural and riparian areas. Grazing effects varied considerably among riparian systems, but avian abundance and richness were significantly lower at grazed survey locations. Fifteen species were significantly less abundant in grazed sites while only five species were more abundant therein. Management should focus on (1) preserving and enlarging deciduous habitats, (2) reducing cattle grazing in deciduous habitats, and (3) protecting the few relatively pristine landscapes surrounding large deciduous riparian areas in the West.

Restoration of the fire-grazing interaction in Artemisia filifolia shrubland of the Southern Great Plains, North America

USGS Publications Warehouse

Winter, Stephen L.; Fuhlendorf, Samuel D.; Goad, Carla L.; Davis, Craig A.; Hickman, Karen R.; Leslie, David M.

2011-01-01

6.Synthesis and applications. Vegetation structure in A. filifolia shrublands of our study was readily altered by the fire–grazing interaction but also demonstrated substantial resilience to these effects. The fire–grazing interaction also changed the total amount of heterogeneity characterizing this system, the scale at which heterogeneity in this system was expressed and the amount of heterogeneity expressed through time. Land managers seeking to impose a shifting mosaic of heterogeneity on this vegetation type can do so by restoring the fire–grazing interaction with potential conservation benefits similar to what has been achieved in other ecosystems where historic cycles of disturbance and rest have been restored.

Field Trial Assessment of Biological, Chemical, and Physical Responses of Soil to Tillage Intensity, Fertilization, and Grazing

NASA Astrophysics Data System (ADS)

Vargas Gil, Silvina; Becker, Analia; Oddino, Claudio; Zuza, Mónica; Marinelli, Adriana; March, Guillermo

2009-08-01

Soil microbial populations can fluctuate in response to environmental changes and, therefore, are often used as biological indicators of soil quality. Soil chemical and physical parameters can also be used as indicators because they can vary in response to different management strategies. A long-term field trial was conducted to study the effects of different tillage systems (NT: no tillage, DH: disc harrow, and MP: moldboard plough), P fertilization (diammonium phosphate), and cattle grazing (in terms of crop residue consumption) in maize ( Zea mays L.), sunflower ( Heliantus annuus L.), and soybean ( Glycine max L.) on soil biological, chemical, and physical parameters. The field trial was conducted for four crop years (2000/2001, 2001/2002, 2002/2003, and 2003/2004). Soil populations of Actinomycetes, Trichoderma spp., and Gliocladium spp. were 49% higher under conservation tillage systems, in soil amended with diammonium phosphate (DAP) and not previously grazed. Management practices also influenced soil chemical parameters, especially organic matter content and total N, which were 10% and 55% higher under NT than under MP. Aggregate stability was 61% higher in NT than in MP, 15% higher in P-fertilized soil, and also 9% higher in not grazed strips, bulk density being 12% lower in NT systems compared with MP. DAP application and the absence of grazing also reduced bulk density (3%). Using conservation tillage systems, fertilizing crops with DAP, and avoiding grazing contribute to soil health preservation and enhanced crop production.

Investigating the Effect of Livestock Grazing and Associated Plant Community Shifts on Carbon and Nutrient Cycling in Alberta, Canada

NASA Astrophysics Data System (ADS)

Hewins, D. B.; Chuan, S.; Stolnikova, E.; Bork, E. W.; Carlyle, C. N.; Chang, S. X.

2015-12-01

Grassland ecosystems are ubiquitous across the globe covering an estimated 40 % of Earth's terrestrial landmass. These ecosystems are widely valued for providing forage for domestic livestock and a suite of important ecosystem goods and services including carbon (C) storage. Despite storing more than 30 % of soil C globally, the effect of both livestock grazing and the associated change in plant community structure in response to grazing on C and nutrient cycling remains uncertain. To gain a quantitative understanding of the direct and indirect effects of livestock grazing on C and nutrient cycling, we established study sites at 15 existing site localities with paired long-term grazing (ca. 30 y) and non-grazed treatments (totaling 30 unique plant communities). Our sites were distributed widely across Alberta in three distinct grassland bioclimatic zones allowing us to make comparisons across the broad range of climate variability typical of western Canadian grasslands. In each plant community we decomposed 5 common plant species that are known to increase or decrease in response to grazing pressure, a unique plant community sample, and a cellulose paper control. We measured mass loss, initial lignin, C and N concentrations at 0, 1, 3, 6 and 12 months of field incubation. In addition we assayed hydrolytic and oxidative extracellular enzymes associated with for C (n= 5 hydrolytic; phenoloxidase and peroxidase) and nutrients (i.e. N and P; n=1 ea.) cycling from each litter sample at each collection. Our results suggest that by changing the plant community structure, grazing can affect rates of decomposition and associated biogeochemical cycling by changing plant species and associated litter inputs. Moreover, measures of microbial function are controlled by site-specific conditions (e.g. temperature and precipitation), litter chemistry over the course of our incubation.

Application of Zoning and ``Limits of Acceptable Change'' to Manage Snorkelling Tourism

NASA Astrophysics Data System (ADS)

Roman, George S. J.; Dearden, Philip; Rollins, Rick

2007-06-01

Zoning and applying Limits of Acceptable Change (LAC) are two promising strategies for managing tourism in Marine Protected Areas (MPAs). Typically, these management strategies require the collection and integration of ecological and socioeconomic data. This problem is illustrated by a case study of Koh Chang National Marine Park, Thailand. Biophysical surveys assessed coral communities in the MPA to derive indices of reef diversity and vulnerability. Social surveys assessed visitor perceptions and satisfaction with conditions encountered on snorkelling tours. Notably, increased coral mortality caused a significant decrease in visitor satisfaction. The two studies were integrated to prescribe zoning and “Limits of Acceptable Change” (LAC). As a biophysical indicator, the data suggest a LAC value of 0.35 for the coral mortality index. As a social indicator, the data suggest that a significant fraction of visitors would find a LAC value of under 30 snorkellers per site as acceptable. The draft zoning plan prescribed four different types of zones: (I) a Conservation Zone with no access apart from monitoring or research; (II) Tourism Zones with high tourism intensities at less vulnerable reefs; (III) Ecotourism zones with a social LAC standard of <30 snorkellers per site, and (IV) General Use Zones to meet local artisanal fishery needs. This study illustrates how ecological and socioeconomic field studies in MPAs can be integrated to craft zoning plans addressing multiple objectives.

Application of zoning and "limits of acceptable change" to manage snorkelling tourism.

PubMed

Roman, George S J; Dearden, Philip; Rollins, Rick

2007-06-01

Zoning and applying Limits of Acceptable Change (LAC) are two promising strategies for managing tourism in Marine Protected Areas (MPAs). Typically, these management strategies require the collection and integration of ecological and socioeconomic data. This problem is illustrated by a case study of Koh Chang National Marine Park, Thailand. Biophysical surveys assessed coral communities in the MPA to derive indices of reef diversity and vulnerability. Social surveys assessed visitor perceptions and satisfaction with conditions encountered on snorkelling tours. Notably, increased coral mortality caused a significant decrease in visitor satisfaction. The two studies were integrated to prescribe zoning and "Limits of Acceptable Change" (LAC). As a biophysical indicator, the data suggest a LAC value of 0.35 for the coral mortality index. As a social indicator, the data suggest that a significant fraction of visitors would find a LAC value of under 30 snorkellers per site as acceptable. The draft zoning plan prescribed four different types of zones: (I) a Conservation Zone with no access apart from monitoring or research; (II) Tourism Zones with high tourism intensities at less vulnerable reefs; (III) Ecotourism zones with a social LAC standard of <30 snorkellers per site, and (IV) General Use Zones to meet local artisanal fishery needs. This study illustrates how ecological and socioeconomic field studies in MPAs can be integrated to craft zoning plans addressing multiple objectives.

Grazing weakens temporal stabilizing effects of diversity in the Eurasian steppe.

PubMed

Ren, Haiyan; Taube, Friedhelm; Stein, Claudia; Zhang, Yingjun; Bai, Yongfei; Hu, Shuijin

2018-01-01

Many biodiversity experiments have demonstrated that plant diversity can stabilize productivity in experimental grasslands. However, less is known about how diversity-stability relationships are mediated by grazing. Grazing is known for causing species losses, but its effects on plant functional groups (PFGs) composition and species asynchrony, which are closely correlated with ecosystem stability, remain unclear. We conducted a six-year grazing experiment in a semi-arid steppe, using seven levels of grazing intensity (0, 1.5, 3.0, 4.5, 6.0, 7.5, and 9.0 sheep per hectare) and two grazing systems (i.e., a traditional, continuous grazing system during the growing period (TGS), and a mixed one rotating grazing and mowing annually (MGS)), to examine the effects of grazing system and grazing intensity on the abundance and composition of PFGs and diversity-stability relationships. Ecosystem stability was similar between mixed and continuous grazing treatments. However, within the two grazing systems, stability was maintained through different pathways, that is, along with grazing intensity, persistence biomass variations in MGS, and compensatory interactions of PFGs in their biomass variations in TGS. Ecosystem temporal stability was not decreased by species loss but rather remain unchanged by the strong compensatory effects between PFGs, or a higher grazing-induced decrease in species asynchrony at higher diversity, and a higher grazing-induced increase in the temporal variation of productivity in diverse communities. Ecosystem stability of aboveground net primary production was not related to species richness in both grazing systems. High grazing intensity weakened the temporal stabilizing effects of diversity in this semi-arid grassland. Our results demonstrate that the productivity of dominant PFGs is more important than species richness for maximizing stability in this system. This study distinguishes grazing intensity and grazing system from diversity effects on

Grazing impacts on infiltration rates at Vernal Pools in the Modoc Plateau

USDA-ARS?s Scientific Manuscript database

Vernal pools are depressions of land that are seasonally inundated with water. They host rare and endemic plant and animal species and are sensitive to livestock grazing management and climate change impacts on hydrology and vegetation. Climate change forecasts predicting a hotter, drier climate sug...

A systematic review of socio-economic assessments in support of coastal zone management (1992-2011).

PubMed

Le Gentil, Eric; Mongruel, Rémi

2015-02-01

Cooperation between the social and natural sciences has become essential in order to encompass all the dimensions of coastal zone management. Socio-economic approaches are increasingly recommended to complement integrated assessment in support of these initiatives. A systematic review of the academic literature was carried out in order to analyze the main types of socio-economic assessments used to inform the coastal zone management process as well as their effectiveness. A corpus of 1682 articles published between 1992 and 2011 was identified by means of the representative coverage approach, from which 170 were selected by applying inclusion/exclusion criteria and then classified using a content analysis methodology. The percentage of articles that mention the use of socio-economic assessment in support of coastal zone management initiatives is increasing but remains relatively low. The review examines the links between the issues addressed by integrated assessments and the chosen analytical frameworks as well as the various economic assessment methods which are used in the successive steps of the coastal zone management process. The results show that i) analytical frameworks such as 'risk and vulnerability', 'DPSIR', 'valuation', 'ecosystem services' and 'preferences' are likely to lead to effective integration of social sciences in coastal zone management research while 'integration', 'sustainability' and 'participation' remain difficult to operationalize, ii) risk assessments are insufficiently implemented in developing countries, and iii) indicator systems in support of multi-criteria analyses could be used during more stages of the coastal zone management process. Finally, it is suggested that improved collaboration between science and management would require that scientists currently involved in coastal zone management processes further educate themselves in integrated assessment approaches and participatory methodologies. Copyright © 2014 Elsevier Ltd

30 CFR 250.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 250.226 Section 250.226 Mineral Resources MINERALS MANAGEMENT SERVICE... and Information Contents of Exploration Plans (ep) § 250.226 What Coastal Zone Management Act (CZMA...

30 CFR 250.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 250.226 Section 250.226 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... Zone Management Act (CZMA) information must accompany the EP? The following CZMA information must...

Traffic incident management in construction and maintenance work zones.

DOT National Transportation Integrated Search

2009-01-01

In 2004, the Federal Highway Administration published updated rules governing work zone safety and mobility; all highway construction and maintenance projects using federal-aid highway funds are required to develop transportation management plans (TM...

25 CFR 700.715 - Assignment, modification, and cancellation of grazing permits.

Code of Federal Regulations, 2011 CFR

2011-04-01

... permit and may be transferred with the term permit if the transferee signs the range unit management plan... not be transferred and shall be null and void if the term permit transferee does not sign the... § 700.711. (d) Grazing permits must be transferred in whole to a single transferee—the transferor...

25 CFR 700.715 - Assignment, modification, and cancellation of grazing permits.

Code of Federal Regulations, 2010 CFR

2010-04-01

... permit and may be transferred with the term permit if the transferee signs the range unit management plan... not be transferred and shall be null and void if the term permit transferee does not sign the... § 700.711. (d) Grazing permits must be transferred in whole to a single transferee—the transferor...

Construction Project Administration and Management for Mitigating Work Zone Accidents and Fatalities: An Integrated Risk Management Model

DOT National Transportation Integrated Search

2009-10-01

The goal of this research is to mitigate the risk of highway accidents (crashes) and fatalities in work zones. The approach of this research has been to address the mitigation of work zone crashes through the creation of a formal risk management mode...

Integrating sheep grazing into wheat-fallow systems: Crop yield and soil properties

USDA-ARS?s Scientific Manuscript database

The two predominant systems for weed management in summer fallow are tillage with a field cultivator or multiple applications of broad spectrum herbicides with zero tillage. Both systems are based on substantial use of off farm resources. Strategic grazing of sheep may allow grain growers to more ...

The effects of grazing by gastropods and physical factors on the upper limits of distribution of intertidal macroalgae.

PubMed

Underwood, A J

1980-01-01

The cover of foliose algae is sparse to non-existent above a low-level algal zone on many shores in N.S.W., except in rock-pools. Above this algal zone, encrusting algae, mostly Hildenbrandia prototypus, occupy most of the primary substratum on sheltered shores. Experimental manipulations at midtidal levels were used to test hypotheses about the effects of grazing by molluses and of physical factors during low tide on this pattern of algal community structure.Fences and cages were used to exclude grazers: molluscs grazed under roofs and in open areas. Cages and roofs provided shade, and decreased the harshness of the environment during low tide: fences and open areas had the normal environmental regime.In the absence of grazers, rapid colonization of Ulva and slower colonization by other foliose algae occurred in all experimental areas. The rate of colonization by Ulva sporelings was initially retarded on existing encrusting algae, but after a few months, cover of Ulva equalled that on cleared rock.Most species of algae only grew to maturity inside cages, and remained as a turf of sporelings inside fences. No foliose algae grew to a visible size in open, grazed areas. Grazing thus prevents the establishment of foliose algae above their normal upper limit on the shore, but the effects of physical factors during low tide prevent the growth of algae which become established when grazers are removed. Physical factors thus limit the abundance of foliose algae at mid-tidal levels.The recolonization of cleared areas by Hildenbrandia was not affected by the presence of a turf of sporelings, nor by the shade cast by roofs, but was retarded in cages where mature algae formed a canopy. Even under such a canopy, Hildenbrandia eventually covered as much primary substratum as in open, grazed areas. This encrusting alga is able to escape from the effects of grazing by having a tough thallus, and by its vegetative growth which allows individual plants to cover a lot of substratum

Should heterogeneity be the basis for conservation? Grassland bird response to fire and grazing

USGS Publications Warehouse

Fuhlendorf, S.D.; Harrell, W.C.; Engle, David M.; Hamilton, R.G.; Davis, C.A.; Leslie, David M.

2006-01-01

In tallgrass prairie, disturbances such as grazing and fire can generate patchiness across the landscape, contributing to a shifting mosaic that presumably enhances biodiversity. Grassland birds evolved within the context of this shifting mosaic, with some species restricted to one or two patch types created under spatially and temporally distinct disturbance regimes. Thus, management-driven reductions in heterogeneity may be partly responsible for declines in numbers of grassland birds. We experimentally altered spatial heterogeneity of vegetation structure within a tallgrass prairie by varying the spatial and temporal extent of fire and by allowing grazing animals to move freely among burned and unburned patches (patch treatment). We contrasted this disturbance regime with traditional agricultural management of the region that promotes homogeneity (traditional treatment). We monitored grassland bird abundance during the breeding seasons of 2001-2003 to determine the influence of altered spatial heterogeneity on the grassland bird community. Focal disturbances of patch burning and grazing that shifted through the landscape over several years resulted in a more heterogeneous pattern of vegetation than uniform application of fire and grazing. Greater spatial heterogeneity in vegetation provided greater variability in the grassland bird community. Some bird species occurred in greatest abundance within focally disturbed patches, while others occurred in relatively undisturbed patches in our patch treatment. Henslow's Sparrow, a declining species, occurred only within the patch treatment. Upland Sandpiper and some other species were more abundant on recently disturbed patches within the same treatment. The patch burn treatment created the entire gradient of vegetation structure required to maintain a suite of grassland bird species that differ in habitat preferences. Our study demonstrated that increasing spatial and temporal heterogeneity of disturbance in grasslands

Eaten Out of House and Home: Impacts of Grazing on Ground-Dwelling Reptiles in Australian Grasslands and Grassy Woodlands

PubMed Central

Howland, Brett; Stojanovic, Dejan; Gordon, Iain J.; Manning, Adrian D.; Fletcher, Don; Lindenmayer, David B.

2014-01-01

Large mammalian grazers can alter the biotic and abiotic features of their environment through their impacts on vegetation. Grazing at moderate intensity has been recommended for biodiversity conservation. Few studies, however, have empirically tested the benefits of moderate grazing intensity in systems dominated by native grazers. Here we investigated the relationship between (1) density of native eastern grey kangaroos, Macropus giganteus, and grass structure, and (2) grass structure and reptiles (i.e. abundance, richness, diversity and occurrence) across 18 grassland and grassy Eucalyptus woodland properties in south-eastern Australia. There was a strong negative relationship between kangaroo density and grass structure after controlling for tree canopy cover. We therefore used grass structure as a surrogate for grazing intensity. Changes in grazing intensity (i.e. grass structure) significantly affected reptile abundance, reptile species richness, reptile species diversity, and the occurrence of several ground-dwelling reptiles. Reptile abundance, species richness and diversity were highest where grazing intensity was low. Importantly, no species of reptile was more likely to occur at high grazing intensities. Legless lizards (Delma impar, D. inornata) were more likely to be detected in areas subject to moderate grazing intensity, whereas one species (Hemiergis talbingoensis) was less likely to be detected in areas subject to intense grazing and three species (Menetia greyii, Morethia boulengeri, and Lampropholis delicata) did not appear to be affected by grazing intensity. Our data indicate that to maximize reptile abundance, species richness, species diversity, and occurrence of several individual species of reptile, managers will need to subject different areas of the landscape to moderate and low grazing intensities and limit the occurrence and extent of high grazing. PMID:25501680

Eaten out of house and home: impacts of grazing on ground-dwelling reptiles in Australian grasslands and grassy woodlands.

PubMed

Howland, Brett; Stojanovic, Dejan; Gordon, Iain J; Manning, Adrian D; Fletcher, Don; Lindenmayer, David B

2014-01-01

Large mammalian grazers can alter the biotic and abiotic features of their environment through their impacts on vegetation. Grazing at moderate intensity has been recommended for biodiversity conservation. Few studies, however, have empirically tested the benefits of moderate grazing intensity in systems dominated by native grazers. Here we investigated the relationship between (1) density of native eastern grey kangaroos, Macropus giganteus, and grass structure, and (2) grass structure and reptiles (i.e. abundance, richness, diversity and occurrence) across 18 grassland and grassy Eucalyptus woodland properties in south-eastern Australia. There was a strong negative relationship between kangaroo density and grass structure after controlling for tree canopy cover. We therefore used grass structure as a surrogate for grazing intensity. Changes in grazing intensity (i.e. grass structure) significantly affected reptile abundance, reptile species richness, reptile species diversity, and the occurrence of several ground-dwelling reptiles. Reptile abundance, species richness and diversity were highest where grazing intensity was low. Importantly, no species of reptile was more likely to occur at high grazing intensities. Legless lizards (Delma impar, D. inornata) were more likely to be detected in areas subject to moderate grazing intensity, whereas one species (Hemiergis talbingoensis) was less likely to be detected in areas subject to intense grazing and three species (Menetia greyii, Morethia boulengeri, and Lampropholis delicata) did not appear to be affected by grazing intensity. Our data indicate that to maximize reptile abundance, species richness, species diversity, and occurrence of several individual species of reptile, managers will need to subject different areas of the landscape to moderate and low grazing intensities and limit the occurrence and extent of high grazing.

30 CFR 550.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 550.226 Section 550.226 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Contents of Exploration Plans (ep) § 550.226 What Coastal Zone Management Act (CZMA...

30 CFR 550.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 2 2014-07-01 2014-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 550.226 Section 550.226 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Contents of Exploration Plans (ep) § 550.226 What Coastal Zone Management Act (CZMA...

30 CFR 550.226 - What Coastal Zone Management Act (CZMA) information must accompany the EP?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the EP? 550.226 Section 550.226 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... and Information Contents of Exploration Plans (ep) § 550.226 What Coastal Zone Management Act (CZMA...

Livestock Grazing as a Driver of Vernal Pool Ecohydrology

NASA Astrophysics Data System (ADS)

Michaels, J.; McCarten, N. F.

2017-12-01

Vernal pools are seasonal wetlands that host rare plant communities of high conservation priority. Plant community composition is largely driven by pool hydroperiod. A previous study found that vernal pools grazed by livestock had longer hydroperiods compared with pools excluded from grazing for 10 years, and suggests that livestock grazing can be used to protect plant diversity. It is important to assess whether observed differences are due to the grazing or due to water balance variables including upland discharge into or out of the pools since no a priori measurements were made of the hydrology prior to grazing. To address this question, in 2016 we compared 15 pools that have been grazed continuously and 15 pools that have been fenced off for over 40 years at a site in Sacramento County. We paired pools based on abiotic characteristics (size, shape, slope, soil type) to minimize natural variation. We sampled vegetation and water depth using Solinst level loggers. We found that plant diversity and average hydroperiod was significantly higher in the grazed pools. We are currently measuring groundwater connectivity and upland inputs in order to compare the relative strength of livestock grazing as a driver of hydroperiod to these other drivers.

Are there consistent grazing indicators in Drylands? Testing plant functional types of various complexity in South Africa's Grassland and Savanna Biomes.

PubMed

Linstädter, Anja; Schellberg, Jürgen; Brüser, Katharina; Moreno García, Cristian A; Oomen, Roelof J; du Preez, Chris C; Ruppert, Jan C; Ewert, Frank

2014-01-01

Despite our growing knowledge on plants' functional responses to grazing, there is no consensus if an optimum level of functional aggregation exists for detecting grazing effects in drylands. With a comparative approach we searched for plant functional types (PFTs) with a consistent response to grazing across two areas differing in climatic aridity, situated in South Africa's grassland and savanna biomes. We aggregated herbaceous species into PFTs, using hierarchical combinations of traits (from single- to three-trait PFTs). Traits relate to life history, growth form and leaf width. We first confirmed that soil and grazing gradients were largely independent from each other, and then searched in each biome for PFTs with a sensitive response to grazing, avoiding confounding with soil conditions. We found no response consistency, but biome-specific optimum aggregation levels. Three-trait PFTs (e.g. broad-leaved perennial grasses) and two-trait PFTs (e.g. perennial grasses) performed best as indicators of grazing effects in the semi-arid grassland and in the arid savanna biome, respectively. Some PFTs increased with grazing pressure in the grassland, but decreased in the savanna. We applied biome-specific grazing indicators to evaluate if differences in grazing management related to land tenure (communal versus freehold) had effects on vegetation. Tenure effects were small, which we mainly attributed to large variability in grazing pressure across farms. We conclude that the striking lack of generalizable PFT responses to grazing is due to a convergence of aridity and grazing effects, and unlikely to be overcome by more refined classification approaches. Hence, PFTs with an opposite response to grazing in the two biomes rather have a unimodal response along a gradient of additive forces of aridity and grazing. The study advocates for hierarchical trait combinations to identify localized indicator sets for grazing effects. Its methodological approach may also be useful

Concentrate Supplement Modifies the Feeding Behavior of Simmental Cows Grazing in Two High Mountain Pastures

PubMed Central

Romanzin, Alberto; Piasentier, Edi

2018-01-01

, eight cows were selected and assigned to two groups: High and Low, supplemented with 4 kg/head/d, and 1 kg/head/d of concentrate respectively. Cows were equipped with a noseband pressure sensor and a pedometer (RumiWatch system, ITIN-HOCH GmbH) to assess grazing, ruminating, and walking behavior. In addition, the plant selection of the animals was assessed. On Poion, increased supplement intake caused a more intense selection of legumes, without affecting feeding and walking times. On Seslerion, grazing time was higher in Low than High. Grazing management in alpine region must take into account the great variability of pastures that largely differ from a floristic and nutritional point of view. PMID:29772724

25 CFR 161.207 - What livestock are authorized to graze?

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false What livestock are authorized to graze? 161.207 Section... LANDS GRAZING PERMITS General Provisions § 161.207 What livestock are authorized to graze? The following livestock are authorized to graze on the Navajo Partitioned Lands: horses, cattle, sheep, goats, mules...

Response of a depleted sagebrush steppe riparian system to grazing control and woody plantings

Treesearch

Warren P. Clary; Nancy L. Shaw; Jonathan G. Dudley; Victoria A. Saab; John W. Kinney; Lynda C. Smithman

1996-01-01

To find out if a depleted riparian system in the sagebrush steppe of eastern Oregon would respond quickly to improved management, five management treatments were applied for 7 years, ranging from ungrazed to heavily grazed treatments, including in some cases, planting of woody species. While the results varied, all treatments were too limited to significantly restore...

Herbaceous stubble height as a warning of impending cattle grazing damage to riparian areas.

Treesearch

Frederick C. Hall; Larry Bryant

1995-01-01

Prevention of damage to riparian areas from cattle grazing is essential for sound watershed management. Various stubble heights of the most palatable species are used to predict when unacceptable impacts-heavy use or trampling, or both-are about to occur. Managers can observe stubble height and usage and recommend moving the cattle if undesirable effects from continued...

Wild Herbivore Grazing Enhances Insect Diversity over Livestock Grazing in an African Grassland System.

PubMed

Pryke, James S; Roets, Francois; Samways, Michael J

2016-01-01

Southern Africa's grassland biodiversity is threatened by habitat transformation such as commercial forestry. Ecological networks (ENs) have been instigated to alleviate the pressure of habitat transformation on local biodiversity. ENs are large scale webs of corridors and patches of natural vegetation criss-crossing production landscapes that can simulate conditions in protected areas (PAs). Many ENs have lost many native large mammal species, which have been replaced by domestic livestock to retain natural grazing dynamics, which could have an impact on the long-term value of ENs for insects. Here we compared dung beetle, butterfly and grasshopper diversity in ENs across a landscape mosaic of timber plantations, where 1) wild megaherbivores were maintained, 2) in ENs where these herbivores were replaced by livestock and, 3) in a nearby World Heritage PA which retained its natural complement of megaherbivores. Sites in the PA far from any plantation were similar in composition to those in the wild grazed EN. Presence of the wild grazers improved the alpha- and beta-diversity of all focal insect taxa when compared to domestic grazing. Furthermore, species composition shows significant differences between the two grazing systems indicating that an assemblage of native large mammals facilitates insect diversity conservation. We support the maintenance or introduction of large native mammals in ENs or similar conservation areas in production landscapes to simulate the ecological conditions and natural heterogeneity in nearby PAs.

Soil quality parameters for row-crop and grazed pasture systems with agroforestry buffers

USDA-ARS?s Scientific Manuscript database

Incorporation of trees and establishment of buffers are practices that can improve soil quality. Soil enzyme activities and water stable aggregates are sensitive indices for assessing soil quality by detecting early changes in soil management. However, studies comparing grazed pasture and row crop...

A multi-criteria inference approach for anti-desertification management.

PubMed

Tervonen, Tommi; Sepehr, Adel; Kadziński, Miłosz

2015-10-01

We propose an approach for classifying land zones into categories indicating their resilience against desertification. Environmental management support is provided by a multi-criteria inference method that derives a set of value functions compatible with the given classification examples, and applies them to define, for the rest of the zones, their possible classes. In addition, a representative value function is inferred to explain the relative importance of the criteria to the stakeholders. We use the approach for classifying 28 administrative regions of the Khorasan Razavi province in Iran into three equilibrium classes: collapsed, transition, and sustainable zones. The model is parameterized with enhanced vegetation index measurements from 2005 to 2012, and 7 other natural and anthropogenic indicators for the status of the region in 2012. Results indicate that grazing density and land use changes are the main anthropogenic factors affecting desertification in Khorasan Razavi. The inference procedure suggests that the classification model is underdetermined in terms of attributes, but the approach itself is promising for supporting the management of anti-desertification efforts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Restoring sand shinnery oak prairies with herbicide and grazing in New Mexico

USGS Publications Warehouse

Zavaleta, Jennifer C.; Haukos, David A.; Grisham, Blake A.; Boal, Clint W.; Dixon, Charles

2016-01-01

Sand shinnery oak (Quercus havardii) prairies are increasingly disappearing and increasingly degraded in the Southern High Plains of Texas and New Mexico. Restoring and managing sand shinnery oak prairie can support biodiversity, specific species of conservation concern, and livestock production. We measured vegetation response to four treatment combinations of herbicide (tebuthiuron applied at 0.60 kg/ha) and moderate-intensity grazing (50% removal of annual herbaceous production) over a 10-year period in a sand shinnery oak prairie of eastern New Mexico. We compared the annual vegetation response to the historical climax plant community (HCPC) as outlined by the U.S. Department of Agriculture Ecological Site Description. From 2 to 10 years postapplication, tebuthiuron-treated plots had reduced shrub cover with twice as much forb and grass cover as untreated plots. Tebuthiuron-treated plots, regardless of the presence of grazing, most frequently met HCPC. Tebuthiuron and moderate-intensity grazing increased vegetation heterogeneity and, based on comparison of the HCPC, successfully restored sand shinnery oak prairie to a vegetation composition similar to presettlement.

Effects of grazing on spatiotemporal variations in community structure and ecosystem function on the grasslands of Inner Mongolia, China.

PubMed

Su, Rina; Cheng, Junhui; Chen, Dima; Bai, Yongfei; Jin, Hua; Chao, Lumengqiqige; Wang, Zhijun; Li, Junqing

2017-02-28

Grasslands worldwide are suffering from overgrazing, which greatly alters plant community structure and ecosystem functioning. However, the general effects of grazing on community structure and ecosystem function at spatial and temporal scales has rarely been examined synchronously in the same grassland. Here, during 2011-2013, we investigated community structure (cover, height, and species richness) and aboveground biomass (AGB) using 250 paired field sites (grazed vs. fenced) across three vegetation types (meadow, typical, and desert steppes) on the Inner Mongolian Plateau. Grazing, vegetation type, and year all had significant effects on cover, height, species richness, and AGB, although the primary factor influencing variations in these variables was vegetation type. Spatially, grazing significantly reduced the measured variables in meadow and typical steppes, whereas no changes were observed in desert steppe. Temporally, both linear and quadratic relationships were detected between growing season precipitation and cover, height, richness, or AGB, although specific relationships varied among observation years and grazing treatments. In each vegetation type, the observed community properties were significantly correlated with each other, and the shape of the relationship was unaffected by grazing treatment. These findings indicate that vegetation type is the most important factor to be considered in grazing management for this semi-arid grassland.

How grazing and soil quality affect native and exotic plant diversity in Rocky Mountain grasslands

USGS Publications Warehouse

Stohlgren, T.J.; Schell, L.D.; Vanden, Heuvel B.

1999-01-01

We used multiscale plots to sample vascular plant diversity and soil characteristics in and adjacent to 26 long-term grazing exclosure sites in Colorado, Wyoming, Montana, and South Dakota, USA. The exclosures were 7-60 yr old (31.2 ?? 2.5 yr, mean ?? 1 SE). Plots were also randomly placed in the broader landscape in open rangeland in the same vegetation type at each site to assess spatial variation in grazed landscapes. Consistent sampling in the nine National Parks, Wildlife Refuges, and other management units yielded data from 78 1000-m2 plots and 780 1-m2 subplots. We hypothesized that native species richness would be lower in the exclosures than in grazed sites, due to competitive exclusion in the absence of grazing. We also hypothesized that grazed sites would have higher native and exotic species richness compared to ungrazed areas, due to disturbance (i.e., the intermediate-disturbance hypothesis) and the conventional wisdom that grazing may accelerate weed invasion. Both hypotheses were soundly rejected. Although native species richness in 1-m2 subplots was significantly higher (P < 0.05) in grazed sites, we found nearly identical native or exotic species richness in 1000-m2 plots in exclosures (31.5 ?? 2.5 native and 3.1 ?? 0.5 exotic species), adjacent grazed plots (32.6 ?? 2.8 native and 3.2 ?? 0.6 exotic species), and randomly selected grazed plots (31.6 ?? 2.9 native and 3.2 ?? 0.6 exotic species). We found no significant differences in species diversity (Hill's diversity indices, N1 and N2), evenness (Hill's ratio of evenness, E5), cover of various life-forms (grasses, forbs, and shrubs), soil texture, or soil percentage of N and C between grazed and ungrazed sites at the 1000-m2 plot scale. The species lists of the long-ungrazed and adjacent grazed plots overlapped just 57.9 ?? 2.8%. This difference in species composition is commonly attributed solely to the difference in grazing regimes. However, the species lists between pairs of grazed plots

Grazing disturbance increases transient but decreases persistent soil seed bank.

PubMed

Ma, Miaojun; Walck, Jeffrey L; Ma, Zhen; Wang, Lipei; Du, Guozhen

2018-04-30

Very few studies have examined whether the impacts of grazing disturbance on soil seed banks occur directly or indirectly through aboveground vegetation and soil properties. The potential role of the seed bank in alpine wetland restoration is also unknown. We used SEM (structural equation modeling) to explore the direct effect of grazing disturbance on the seed bank and the indirect effect through aboveground vegetation and soil properties. We also studied the role of the seed bank on the restoration potential in wetlands with various grazing intensities: low (fenced, winter grazed only), medium (seasonally grazed), and high (whole-year grazed). For the seed bank, species richness and density per plot showed no difference among grazing intensities for each depth (0-5, 5-10, 10-15 cm) and for the whole depth (0-15 cm) in spring and summer. There was no direct effect of grazing disturbance on seed bank richness and density both in spring and summer, and also no indirect effect on the seed bank through its direct effect on vegetation richness and abundance. Grazing disturbance indirectly increased spring seed bank density but decreased summer seed bank density through its direct effect (negative correlation) on soil moisture and total nitrogen and its indirect effect on vegetation abundance. Species composition of the vegetation changed with grazing regime, but that of the seed bank did not. An increased trend of similarity between the seed bank and aboveground vegetation with increased grazing disturbance was found in the shallow depth and in the whole depth only in spring. Although there was almost no change in seed bank size with grazing intensities, grazing disturbance increased the quantity of transient seeds but decreased persistent seeds. Persistent seeds stored in the soil could play a crucial role in vegetation regeneration and in restoration of degraded wetland ecosystems. The seed bank should be an integral part of alpine wetland restoration programs. �

Indicators of grazing impact in Inner Mongolian steppe ecosystems

NASA Astrophysics Data System (ADS)

Blank, B.; Breuer, L.; Butterbach-Bahl, K.; Frede, H.-G.

2009-04-01

The DFG research group 536 MAGIM (Matter fluxes in grasslands of Inner Mongolia as influenced by stocking rate) investigates the influence of grazing intensity on matter and water cycles in grazed steppe ecosystems of Inner Mongolia. This Sino-German co-operation applies an interdisciplinary approach to investigate major ecosystem functions and how they are affected by grazing and overgrazing. Within the research group an indicator system is developed to systemize the feedback of ecosystem parameters to the influence of grazing and to analyse, which parameter or parameter group reacts most sensitively. Parameters were measured at up to five different grazing intensities (from ungrazed to heavy grazed) and are related to four thematic indicator groups (plant productivity, atmosphere, pedosphere, hydrosphere). The parameters were scaled to allow assessing the influence of grazing intensity between different sets of parameters. For this the average value of a parameter at the lowest grazing intensity (ungrazed) was set 100%, so that the values at the other intensities could be scaled scaled adequately. Then the difference between highest and lowest grazing intensity was determined. According to this difference the influence of grazing was characterized as weak (< 20% difference), medium (20-40%), strong (40-60%) and very strong (> 60%). Impact of grazing on the parameters will be marked as weak (w), medium (m), strong (s) and very strong (vs) in the text. The group plant productivity includes the vegetation parameters aboveground biomass and belowground biomass. Belowground biomass (s) was significantly different between grazing treatments with the highest value at the ungrazed site (399.00 g m-2 a-1) and the lowest at the heavy grazed site (208.00 g m-2 a-1). Aboveground biomass (m) ranged between 91.33-131.67 g m-2 a-1 and differed significantly between the ungrazed and the heavy grazed site, again with higher values at the ungrazed site (Gao et al. 2008). The group

Sequence Grazing of Perennial and Annual Cool-Season Grasses to Extend the Grazing Season for Stocker Calves

USDA-ARS?s Scientific Manuscript database

Grazing of cool-season grasses by beef calves before entry into the feedlot for finishing is an important component of the US beef production system. The length of time in the feedlot and the quantity of feed grain required to reach market BW would be reduced if more BW was gained during the grazing...

A narrower gap of grazing intensity. Reply to Fetzel et al. 2017. Seasonality constrains to livestock grazing intensity

USDA-ARS?s Scientific Manuscript database

Fetzel et al. (2017) globally mapped the gap between observed and potential grazing intensity (GI): the ratio between consumption by livestock and ANPP. Fetzel et al. (2017) estimated grazing land, forage production and livestock demand at a half-degree resolution. They mapped GI below 15% for most ...

Reindeer grazing in subarctic boreal forest - influences on the soil carbon dynamics

NASA Astrophysics Data System (ADS)

Koster, Kajar; Berninger, Frank; Köster, Egle; Pumpanen, Jukka

2015-04-01

Reindeer (Rangifer tarandus L.) are the most important large mammalian herbivores in the northern ecosystems , which have many effects on plant diversity, soil nutrient cycling and soil organic matter decomposition. Changes caused by reindeer in vegetation have indirect effects on physical features of the soil e.g. soil microclimate, root biomass and also on soil C dynamics. Earlier, the role of reindeer grazing in ground vegetation dynamics and in soil carbon (C) dynamics has been mostly investigated in open tundra heaths. The objectives of this study were to examine if and how the reindeer grazing (and the possible temperature changes in soil caused by heavy grazing) is affecting the soil C dynamics (CO2 efflux from the soil, C storage in soil, microbial biomass in the soil). In a field experiment in Finnish Lapland, in Värriö Strict Nature Reserve (67° 46' N, 29° 35' E) we have assessed the changes occurring in above- and belowground biomasses, and soil C dynamics (CO2 efflux, soil C content, soil microbial biomass C) among areas grazed and ungrazed by reindeer. Our study areas are located in the northern boreal subarctic coniferous forest at the zone of the last intact forest landscapes in Fennoscandia, where large areas of relatively undisturbed subarctic Scots pine (Pinus sylvestris L.) forests can still be found. The sample plots located in the Värriö Strict Nature Reserve (10 sample plots in total established in year 2013) are situated along the borderline between Finland and Russia, where the ungrazed area was excluded from the reindeer grazing already in 1918, to prevent the Finnish reindeer from going to the Russian side and there are not many reindeer on Russian side of the area. To characterize the stands we have established circular sample plots on areas with a radius of 11.28 m, where different tree characteristics were measured (diameter at 1.3 m, height, height of a tree, crown height, crown diameter, stand age, etc.). On every sample plot

Effects of sequential treatments with eprinomectin on performance and grazing behaviour in dairy cattle under daily-paddock stocking management.

PubMed

Gibb, M J; Huckle, C A; Forbes, A B

2005-10-10

To evaluate the effect of gastrointestinal parasites on grazing behaviour, herbage intake and milk production in spring calving dairy cows, 12 naturally infected control cows were compared with 12 similar animals treated on three occasions (June, July and September) with eprinomectin. The cows were blocked according to calving date, parity, live weight and milk yield during week 2 after turnout and then allocated to the treatments. The grazing area was sub-divided into two sets of 12 replicated paddocks of equivalent size and topography. Pairs of either control or treated animals were randomly assigned to graze each paddock over the duration of the study. Within each plot, the pair of cows grazed a series of 1-day paddocks, of areas calculated to provide 72 kg of herbage dry matter measured to ground level. Faecal samples were collected from each cow in April, prior to allocation, and every 28 days thereafter. Samples were submitted for counts of nematode eggs (sensitivity 1 epg) and the presence of Dictyocaulus viviparus larvae. Additional faecal samples were taken on each occasion for culture and nematode identification. Pasture samples for direct larval counts were collected at the same time as faecal sampling. Behaviour measurements on all cows were made during three periods, once before the first treatment with eprinomectin and thence after the 2nd and 3rd treatments. During each behaviour measurement period, grazing and ruminating behaviour were recorded over two 24-h periods and measurements of components of short-term intake rate were made during a morning and a late afternoon grazing meal. Milk yield was recorded daily and milk quality was recorded weekly. Live weight and body condition score were recorded on the day of allocation, the day of initial treatment and thereafter at weekly intervals until the end of the trial. The parasitological results showed low levels of faecal egg output throughout the study with group arithmetic means ranging from 0 to 6

A two reservoir model to predict Escherichia coli losses to water from pastures grazed by dairy cows.

PubMed

Muirhead, R W; Monaghan, R M

2012-04-01

Animal agriculture has been identified as an important source of diffuse faecal microbial pollution of water. Our current understanding of the losses of faecal microbes from grazed pasture systems is however poor. To help synthesise our current knowledge, a simple two reservoir model was constructed to represent the faecal and environmental sources of Escherichia coli found in a grazed pastoral system. The size of the faecal reservoir was modelled on a daily basis with inputs from grazing animals, and losses due to die-off of E. coli and decomposition of the faecal material. Estimates were made of transport coefficients of E. coli losses from the two reservoirs. The concentration of E. coli measured in overland flow and artificial drainage from grazed plots, used for calibration of the model, showed a significant (P<0.0001) decrease with days since last grazing - up to 120 days. Modelled E. coli runoff concentrations calibrated well with the regression line from the measured data up to 120 days. Variability of E. coli concentrations in the source faecal material could account for the variability in the measured runoff concentrations. Measured E. coli concentrations in artificial drainage water from 120 to 1300 days since last grazing appeared to be greater than the model predicted. The longer term data clearly illustrated the need for an environmental reservoir of E. coli in models of grazed pasture systems. Research is needed to understand the behaviour and impact of this environmental reservoir. Scenario analysis using the model indicated that rather than manipulating the faecal material itself post defecation, mitigation options should focus on manipulating grazing management. Copyright © 2011 Elsevier Ltd. All rights reserved.

Grazing management effects on stream bank erosion and phosphorus delivery to a pasture stream

USDA-ARS?s Scientific Manuscript database

Pasture lands may deliver significant sediment and phosphorus (P) to surface waters. To determine the effects of beef (Bos taurus) grazing practices on stream bank erosion and P losses, three treatments [rotational stocking (RS), continuous stocking with restricted stream access (CSR), and continuou...

Wild Herbivore Grazing Enhances Insect Diversity over Livestock Grazing in an African Grassland System

PubMed Central

Roets, Francois; Samways, Michael J.

2016-01-01

Southern Africa’s grassland biodiversity is threatened by habitat transformation such as commercial forestry. Ecological networks (ENs) have been instigated to alleviate the pressure of habitat transformation on local biodiversity. ENs are large scale webs of corridors and patches of natural vegetation criss-crossing production landscapes that can simulate conditions in protected areas (PAs). Many ENs have lost many native large mammal species, which have been replaced by domestic livestock to retain natural grazing dynamics, which could have an impact on the long-term value of ENs for insects. Here we compared dung beetle, butterfly and grasshopper diversity in ENs across a landscape mosaic of timber plantations, where 1) wild megaherbivores were maintained, 2) in ENs where these herbivores were replaced by livestock and, 3) in a nearby World Heritage PA which retained its natural complement of megaherbivores. Sites in the PA far from any plantation were similar in composition to those in the wild grazed EN. Presence of the wild grazers improved the alpha- and beta-diversity of all focal insect taxa when compared to domestic grazing. Furthermore, species composition shows significant differences between the two grazing systems indicating that an assemblage of native large mammals facilitates insect diversity conservation. We support the maintenance or introduction of large native mammals in ENs or similar conservation areas in production landscapes to simulate the ecological conditions and natural heterogeneity in nearby PAs. PMID:27783685

Environmental management zoning for coal mining in mainland China based on ecological and resources conditions.

PubMed

Geng, Haiqing; Chen, Fan; Wang, Zhiyuan; Liu, Jie; Xu, Weihua

2017-05-01

The purpose of this research is to establish an environmental management zoning for coal mining industry which is served as a basis for making environmental management policies. Based on the specific impacts of coal mining and regional characteristics of environment and resources, the ecological impact, water resources impact, and arable land impact are chose as the zoning indexes to construct the index system. The ecological sensitivity is graded into three levels of low, medium, and high according to analytical hierarchy processes and gray fixed weight clustering analysis, and the water resources sensitivity is divided into five levels of lower, low, medium, high, and higher according to the weighted sum of sub-indexes, while only the arable land sensitive zone was extracted on the basis of the ratio of arable land to the county or city. By combining the ecological sensitivity zoning and the water resources sensitive zoning and then overlapping the arable-sensitive areas, the mainland China is classified into six types of environmental management zones for coal mining except to the forbidden exploitation areas.

76 FR 23708 - Safety Zone; Pierce County Department of Emergency Management Regional Water Exercise, East...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-28

...-AA00 Safety Zone; Pierce County Department of Emergency Management Regional Water Exercise, East... the Regional Water Rescue Exercise. Basis and Purpose The Pierce County, Washington, Department of... to read as follows: Sec. 165.T13-0251 Safety Zone; Pierce County Department of Emergency Management...

Developmental instability and fitness in Periploca laevigata experiencing grazing disturbance

USGS Publications Warehouse

Alados, C.L.; Giner, M.L.; Dehesa, L.; Escos, J.; Barroso, F.; Emlen, J.M.; Freeman, D.C.

2002-01-01

We investigated the sensitivity of developmental instability measurements (leaf fluctuating asymmetry, floral radial asymmetry, and shoot translational asymmetry) to a long‐standing natural stress (grazing) in a palatable tannin‐producing shrub (Periploca laevigata Aiton). We also assessed the relationship between these measures of developmental instability and fitness components (growth and floral production). Developmental instability, measured by translational asymmetry, was the most accurate estimator of a plant’s condition and, consequently, environmental stress. Plants with less translational asymmetry grew more and produced more flowers. Plants from the medium‐grazed population were developmentally more stable, as estimated by translational and floral asymmetry, than either more heavily or more lightly grazed populations. Leaf fluctuating asymmetry was positively correlated with tannin concentration. The pattern of internode growth also responded to grazing impact. Plants under medium to heavy grazing pressure accelerated early growth and consequently escaped herbivory later in the season, i.e., at the beginning of the spring, when grazing activity was concentrated in herbaceous plants. Periploca laevigata accelerated growth and finished growing sooner than in the other grazing treatment. Thus, its annual growth was more mature and less palatable later in the season when grazers typically concentrate on shrubs. The reduction of developmental instability under medium grazing is interpreted as a direct effect of grazing and not as the release from competition.

Development of a lifetime merit-based selection index for US dairy grazing systems

USDA-ARS?s Scientific Manuscript database

Pasture-based dairy producers in the US face costs, revenues and management challenges that differ from those associated with conventional dairy production systems. Three Grazing Merit indexes (GM$1, GM$2, and GM$3), parallel to the US Lifetime Net Merit (NM$) index, were constructed using economic ...

Transcriptome responses in alfalfa associated with tolerance to intensive animal grazing

PubMed Central

Wang, Junjie; Zhao, Yan; Ray, Ian; Song, Mingzhou

2016-01-01

Tolerance of alfalfa (Medicago sativa L.) to animal grazing varies widely within the species. However, the molecular mechanisms influencing the grazing tolerant phenotype remain uncharacterized. The objective of this study was to identify genes and pathways that control grazing response in alfalfa. We analyzed whole-plant de novo transcriptomes from grazing tolerant and intolerant populations of M. sativa ssp. falcata subjected to grazing by sheep. Among the Gene Ontology terms which were identified as grazing responsive in the tolerant plants and differentially enriched between the tolerant and intolerant populations (both grazed), most were associated with the ribosome and translation-related activities, cell wall processes, and response to oxygen levels. Twenty-one grazing responsive pathways were identified that also exhibited differential expression between the tolerant and intolerant populations. These pathways were associated with secondary metabolite production, primary carbohydrate metabolic pathways, shikimate derivative dependent pathways, ribosomal subunit composition, hormone signaling, wound response, cell wall formation, and anti-oxidant defense. Sequence polymorphisms were detected among several differentially expressed homologous transcripts between the tolerant and intolerant populations. These differentially responsive genes and pathways constitute potential response mechanisms for grazing tolerance in alfalfa. They also provide potential targets for molecular breeding efforts to develop grazing-tolerant cultivars of alfalfa. PMID:26763747

Integrating space and time: A case for phenological context in grazing studies and management

USDA-ARS?s Scientific Manuscript database

In water-limited landscapes, patterns in primary production are highly variable across space and time. Livestock grazing is a common agricultural practice worldwide and a concern is localized overuse of specific pasture resources that can exacerbate grass losses and soil erosion. On a research ranch...

Near grazing scattering from non-Gaussian ocean surfaces

NASA Technical Reports Server (NTRS)

Kim, Yunjin; Rodriguez, Ernesto

1993-01-01

We investigate the behavior of the scattered electromagnetic waves from non-Gaussian ocean surfaces at near grazing incidence. Even though the scattering mechanisms at moderate incidence angles are relatively well understood, the same is not true for near grazing rough surface scattering. However, from the experimental ocean scattering data, it has been observed that the backscattering cross section of a horizontally polarized wave can be as large as the vertical counterpart at near grazing incidence. In addition, these returns are highly intermittent in time. There have been some suggestions that these unexpected effects may come from shadowing or feature scattering. Using numerical scattering simulations, it can be shown that the horizontal backscattering cannot be larger than the vertical one for the Gaussian surfaces. Our main objective of this study is to gain a clear understanding of scattering mechanisms underlying the near grazing ocean scattering. In order to evaluate the backscattering cross section from ocean surfaces at near grazing incidence, both the hydrodynamic modeling of ocean surfaces and an accurate near grazing scattering theory are required. For the surface modeling, we generate Gaussian surfaces from the ocean surface power spectrum which is derived using several experimental data. Then, weakly nonlinear large scale ocean surfaces are generated following Longuet-Higgins. In addition, the modulation of small waves by large waves is included using the conservation of wave action. For surface scattering, we use MOM (Method of Moments) to calculate the backscattering from scattering patches with the two scale shadowing approximation. The differences between Gaussian and non-Gaussian surface scattering at near grazing incidence are presented.

Optimized active traffic management and speed harmonization in work zones.

DOT National Transportation Integrated Search

2014-01-01

Traffic and demand management are major strategies to control delay and congestion in : highway bottlenecks including work zones. The Federal Highway Administration (FHWA) : introduced innovative strategies, called Active Traffic and Demand Managemen...

MEASURING INVERTEBRATE GRAZING ON SEAGRASSES AND EPIPHYTES

EPA Science Inventory

The chapter describes methods to assess grazing rates, grazer preferences, and grazer impacts, by mobile organisms living in the canopy or in the rhizome layer in any seagrass system. One set of methods quantifies grazing activity in small to medium sized, mobile organisms livin...

Feedback dynamics of grazing lawns: Coupling vegetation change with animal growth

USGS Publications Warehouse

Person, Brian T.; Herzog, M.P.; Ruess, Roger W.; Sedinger, J.S.; Anthony, R. Michael; Babcock, C.A.

2003-01-01

We studied the effects of grazing by Black Brant (Branta bernicla nigricans) geese (hereafter Brant) on plant community zonation and gosling growth between 1987 and 2000 at a nesting colony in southwestern Alaska. The preferred forage of Brant, Carex subspathacea, is only found as a grazing lawn. An alternate forage species, C. ramenskii, exists primarily as meadow but also forms grazing lawns when heavily grazed. We mowed plots of ungrazed C. ramenskii meadows to create swards that Brant could select and maintain as grazing lawns. Fecal counts were higher on mowed plots than on control plots in the year after plots were mowed. Both nutritional quality and aboveground biomass of C. ramenskii in mowed plots were similar to that of C. subspathacea grazing lawns. The areal extent of grazing lawns depends in part on the population size of Brant. High Brant populations can increase the areal extent of grazing lawns, which favors the growth of goslings. Grazing lawns increased from 3% to 8% of surface area as the areal extent of C. ramenskii meadows declined between 1991 and 1999. Gosling mass was lower early in this time period due to density dependent effects. As the goose population stabilized, and area of grazing lawns increased, gosling mass increased between 1993 and 1999. Because larger goslings have increased survival, higher probability of breeding, and higher fecundity, herbivore-mediated changes in the distribution grazing lawn extent may result in a numerical increase of the population within the next two decades.

The influence of grazing on surface climatological variables of tallgrass prairie

NASA Technical Reports Server (NTRS)

Seastedt, T. R.; Dyer, M. I.; Turner, Clarence L.

1992-01-01

Mass and energy exchange between most grassland canopies and the atmosphere are mediated by grazing activities. Ambient temperatures can be increased or decreased by grazers. Data have been assembled from simulated grazing experiments on Konza Prairie Research Natural Area and observations on adjacent pastures grazed by cattle show significant changes in primary production, nutrient content, and bidirectional reflectance characteristics as a function of grazing intensity. The purpose of this research was to provide algorithms that would allow incorporation of grazing effects into models of energy budgets using remote sensing procedures. The approach involved: (1) linking empirical measurements of plant biomass and grazing intensities to remotely sensed canopy reflectance, and (2) using a higher resolution, mechanistic grazing model to derive plant ecophysiological parameters that influence reflectance and other surface climatological variables.

Effects of soils and grazing on breeding birds of uncultivated upland grasslands of the Northern Great Plains

USGS Publications Warehouse

Kantrud, H.A.; Kologiski, R.L.

1982-01-01

The principal use of uncultivated upland grasslands in the northern Great Plains is for livestock production. However, on lands set aside for wildlife or for scientific or recreational use, grazing by livestock may be used as a management measure to enhance populations of game species or to create conditions that increase the diversity of plant or animal species. To determine the effects of grazing on the avifauna of various types of Great Plains grasslands, we conducted bird censuses and plant surveys during 1974-78 on 615 plots of lightly, moderately, or heavily grazed native rangeland.Numbers of horned lark (Eremophila alpestris), western meadowlark (Sturnella neglecta), lark bunting (Calamospiza melanocorys), and chestnut-collared longspur (Calcarius ornatus) accounted for 65-75% of the total bird population, regardless of grazing intensity. For the entire area sampled (600,000 km2), horned lark, western meadowlark, and chestnut-collared longspur were the dominant birds. Major differences in composition of the dominant species and species richness occurred among the major soils. Increased mean annual soil temperature seemingly had a greater negative influence on avian species richness than did decreased soil moisture or organic matter content. Differences in total bird density were not significant among soils and among grazing intensities within most soils. For the area as a whole, light or moderate grazing resulted in increased species richness. Of the 29 species studied, 2 responded significantly to grazing for the area as a whole and 6 others to grazing on the soil in which peak densities occurred. Response of several other species to grazing effects evidently varied among strata.A list of plants with mean cover values of more than 1% in any of the 18 combinations of soils and grazing intensities contained less than 25 species, attesting to the relative simplicity of the grassland vegetation in the northern Great Plains. Agropyron spp. and Bouteloua gracilis

Knowledge and tools to enhance resilience of beef grazing systems for sustainable animal protein production.

PubMed

Steiner, Jean L; Engle, David M; Xiao, Xiangming; Saleh, Ali; Tomlinson, Peter; Rice, Charles W; Cole, N Andy; Coleman, Samuel W; Osei, Edward; Basara, Jeffrey; Middendorf, Gerad; Gowda, Prasanna; Todd, Richard; Moffet, Corey; Anandhi, Aavudai; Starks, Patrick J; Ocshner, Tyson; Reuter, Ryan; Devlin, Daniel

2014-11-01

Ruminant livestock provides meat and dairy products that sustain health and livelihood for much of the world's population. Grazing lands that support ruminant livestock provide numerous ecosystem services, including provision of food, water, and genetic resources; climate and water regulation; support of soil formation; nutrient cycling; and cultural services. In the U.S. southern Great Plains, beef production on pastures, rangelands, and hay is a major economic activity. The region's climate is characterized by extremes of heat and cold and extremes of drought and flooding. Grazing lands occupy a large portion of the region's land, significantly affecting carbon, nitrogen, and water budgets. To understand vulnerabilities and enhance resilience of beef production, a multi-institutional Coordinated Agricultural Project (CAP), the "grazing CAP," was established. Integrative research and extension spanning biophysical, socioeconomic, and agricultural disciplines address management effects on productivity and environmental footprints of production systems. Knowledge and tools being developed will allow farmers and ranchers to evaluate risks and increase resilience to dynamic conditions. The knowledge and tools developed will also have relevance to grazing lands in semiarid and subhumid regions of the world. © 2014 New York Academy of Sciences.

The effect of grazing exclusion over time on structure, biodiversity, and regeneration of high nature value farmland ecosystems in Europe.

PubMed

Listopad, Claudia M C S; Köbel, Melanie; Príncipe, Adriana; Gonçalves, Paula; Branquinho, Cristina

2018-01-01

Climate change and increasing socio-economic pressure is placing many ecosystems of high ecological and economic value at risk. This is particularly urgent in dryland ecosystems, such as the montado, a multifunctional savannah-like system heavily modeled by grazing. There is still an ongoing debate about the trade-offs between livestock grazing and the potential for ecosystem regeneration. While it is consensual that overgrazing hinders the development of the shrubs and trees in this system, the effects of undergrazing or grazing exclusion are unclear. This study provides the unique opportunity to study the impact of grazing on compositional and structural biodiversity by examining the ecological chronosequence in a long-term ecological research site, located in Portugal, where grazing exclusion was controlled for over 15years. As the threat of intensification persists, even in areas where climate shifts are evident, there is a critical need to understand if and how the montado might recover by removing grazing pressure. We evaluate succession on structural and compositional diversity after grazing pressure is removed from the landscape at 5, 10, and 15years post-cattle exclusion and contrast it with currently grazed plots. A LiDAR-derived structural diversity index (LHDI), a surrogate of ecosystem structure and function first developed for the pine-grassland woodland systems, is used to quantify the impact of grazing exclusion on structure and natural regeneration. The distribution of the vegetation, particularly those of the herbaceous and shrub strata (>10≤150cm), presents statistically significant changes. The LHDI closely mimics the compositional biodiversity of the shrubs, with an increase in diversity with increased years without grazing. Under present climate conditions, both shrub regeneration and the establishment of tree saplings were strongly promoted by grazing exclusion, which has important management implications for the long-term sustainability of

Grazing behavior and production characteristics among cows differing in residual feed intake while grazing late season Idaho rangeland

USDA-ARS?s Scientific Manuscript database

The objectives were to determine if cows classified as either low- or high-residual feed intake (LRFI or HRFI) differed in BW, BCS, and winter grazing activity over time. Thirty Hereford x Angus (LRFI = 16; HRFI = 14) 2-year-old cows grazed sagebrush-steppe for 78 d beginning 29 September 2016. Body...

Using packrat middens to assess grazing effects on vegetation change

USGS Publications Warehouse

Fisher, J.; Cole, K.L.; Anderson, R. Scott

2009-01-01

Research on grazing effects usually compares the same sites through time or grazed and ungrazed sites over the same time period. Both approaches are complicated in arid environments where grazing can have a long undocumented history and landscapes can be spatially heterogenous. This work employs both approaches simultaneously by comparing grazed and ungrazed samples through both time and space using fossil plant macrofossils and pollen from packrat middens. A series of 27 middens, spanning from 995 yr BP to the present, were collected from Glen Canyon in southeastern Utah, USA. These middens detail vegetation change just prior to, and following, the historical introduction of domesticated grazers and also compares assemblages from nearby ungrazable mesas. Pre-grazing middens, and modern middens from ungrazed areas, record more native grasses, native herbs, and native shrubs such as Rhus trilobata, Amelanchier utahensis, and Shepherdia rotundifolia than modern middens from grazed areas. Ordinations demonstrate that site-to-site variability is more important than any temporal changes, making selection of comparable grazed versus ungrazed study treatments difficult. But within similar sites, the changes through time show that grazing lowered the number of taxa recorded, and lessened the pre-existing site differences, homogenizing the resultant plant associations in this desert grassland.

25 CFR 166.400 - Who establishes grazing rental rates?

Code of Federal Regulations, 2010 CFR

2010-04-01

... rental rate that is less or more than the grazing rental rate established by us. We will assist a tribe... under paragraph (a) of this section. (c) Indian landowners may give us written authority to grant... grazing rental rate set by us; or (2) Below the grazing rental rate set by us, subject to our approval...

INVITED REVIEW: Getting more information from your grazing research beyond cattle performance 1,2

USDA-ARS?s Scientific Manuscript database

Research examining the nutrition of grazing ruminants can be a rewarding career; however, this type of science possesses great challenges. This type of research requires the scientist to make many assumptions, deal with great variability across a landscape, and requires careful planning to manage t...

Effects of co-grazing dairy heifers with goats on animal performance, dry matter yield, and pasture forage composition.

PubMed

Dennis, T S; Unruh-Snyder, L J; Neary, M K; Nennich, T D

2012-12-01

Mixed livestock grazing can offer an alternative management system for rearing dairy replacement heifers (Bos taurus). A 2-yr study was conducted during 2009 (yr 1) and 2010 (yr 2) to determine the effects of co-grazing Holstein heifers under rotational stocking with Boer × Kiko goats on animal performance, pasture DM yield, and botanical composition. Each year, 24 heifers (134 ± 6 d of age and 147.4 ± 31.2 kg BW in yr 1; 166 ± 11 d of age and 168.0 ± 27.6 kg BW in yr 2) and 6 goats (2 yr old and 39.7 ± 16.2 kg BW in yr 1; 1 yr old and 33.7 ± 7.4 kg BW in yr 2) were divided into 6 paddocks with 4 heifers and 2 goats, where applicable, per group. Low endophyte-infected tall fescue (Festuca arundinacea Schreb.) and white clover (Trifolium repens L.) pastures were used to evaluate 2 grazing strategies (heifers grazed alone [HO] or heifers co-grazed with goats [HG]). In addition, 6 goats were assigned to 2 paddocks and grazed alone (GO) each year to estimate goat pasture forage intake and compare Haemonchus contortus infection to co-grazed goats. Forage samples were taken monthly to assess DM yield and botanical composition. Samples collected for botanical composition were manually sorted into grass, legume, and weed species. Forage DMI was estimated using a rising plate meter before and after grazing. Heifer BW at the conclusion of yr 1 and yr 2 did not differ between HO and HG (P = 0.40 and P = 0.12, respectively). Likewise, overall ADG did not differ between HO and HG, averaging 0.65 kg/d and 0.63 kg/d over both grazing seasons (P = 0.70). Grazing strategy did not affect forage or total DMI in yr 1; however, HO consumed 2.3 kg/d more forage DM than HG (P < 0.01), resulting in greater total DMI for HO in yr 2 (P < 0.01). Heights at the hip and withers were greater for HO than for HG during both grazing seasons (P < 0.05). Weed presence did not differ between grazing strategies over both grazing seasons as determined by manual harvesting, but visual estimation

Are There Consistent Grazing Indicators in Drylands? Testing Plant Functional Types of Various Complexity in South Africa’s Grassland and Savanna Biomes

PubMed Central

Linstädter, Anja; Schellberg, Jürgen; Brüser, Katharina; Moreno García, Cristian A.; Oomen, Roelof J.; du Preez, Chris C.; Ruppert, Jan C.; Ewert, Frank

2014-01-01

Despite our growing knowledge on plants’ functional responses to grazing, there is no consensus if an optimum level of functional aggregation exists for detecting grazing effects in drylands. With a comparative approach we searched for plant functional types (PFTs) with a consistent response to grazing across two areas differing in climatic aridity, situated in South Africa’s grassland and savanna biomes. We aggregated herbaceous species into PFTs, using hierarchical combinations of traits (from single- to three-trait PFTs). Traits relate to life history, growth form and leaf width. We first confirmed that soil and grazing gradients were largely independent from each other, and then searched in each biome for PFTs with a sensitive response to grazing, avoiding confounding with soil conditions. We found no response consistency, but biome-specific optimum aggregation levels. Three-trait PFTs (e.g. broad-leaved perennial grasses) and two-trait PFTs (e.g. perennial grasses) performed best as indicators of grazing effects in the semi-arid grassland and in the arid savanna biome, respectively. Some PFTs increased with grazing pressure in the grassland, but decreased in the savanna. We applied biome-specific grazing indicators to evaluate if differences in grazing management related to land tenure (communal versus freehold) had effects on vegetation. Tenure effects were small, which we mainly attributed to large variability in grazing pressure across farms. We conclude that the striking lack of generalizable PFT responses to grazing is due to a convergence of aridity and grazing effects, and unlikely to be overcome by more refined classification approaches. Hence, PFTs with an opposite response to grazing in the two biomes rather have a unimodal response along a gradient of additive forces of aridity and grazing. The study advocates for hierarchical trait combinations to identify localized indicator sets for grazing effects. Its methodological approach may also be

77 FR 28854 - Proposed Information Collection; Comment Request; Coastal Zone Management Program Administration

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-16

... federally approved coastal management programs; complete information for the Coastal Zone Management Program.... Gwellnar Banks, Management Analyst, Office of the Chief Information Officer. [FR Doc. 2012-11777 Filed 5-15... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Proposed Information...

Simulated grazing responses on the proposed prairies National Park

NASA Astrophysics Data System (ADS)

Parton, William J.; Wright, R. Gerald; Risser, Paul G.

1980-03-01

The tallgrass prairie version of the ELM Grassland Model was used to evaluate the potential impact of establishing a tallgrass prairie National Park in the Flint Hills region of Kansas. This total ecosystem model simulates ( a) the flow of water, heat, nitrogen, and phosphorus through the ecosystem and( b) the biomass dynamics of plants and consumers. It was specifically developed to study the effects of levels and types of herbivory, climatic variation, and fertilization upon grassland ecosystems. The model was used to simulate the impact of building up herds of bison, elk, antelope, and wolves on a tallgrass prairie. The results show that the grazing levels in the park should not be decreased below the prepark grazing levels (moderate grazing with cattle) and that the final grazing levels in the park could be maintained at a slightly higher level than the prepark grazing levels.

Mycobacterium tuberculosis infection in grazing cattle in central Ethiopia.

PubMed

Ameni, Gobena; Vordermeier, Martin; Firdessa, Rebuma; Aseffa, Abraham; Hewinson, Glyn; Gordon, Stephen V; Berg, Stefan

2011-06-01

A preliminary study to characterise mycobacteria infecting tuberculous cattle from two different management systems in central Ethiopia was carried out. Approximately 27% of isolates from grazing cattle were Mycobacterium tuberculosis, while cattle in a more intensive-production system were exclusively infected with M. bovis. The practice of local farmers discharging chewed tobacco directly into the mouths of pastured cattle was identified as a potential route of human-to-cattle transmission of M. tuberculosis. Copyright © 2010 Elsevier Ltd. All rights reserved.

Effect of increased concentrate allotment before evening grazing on herbage intake, nitrogen utilization and rumen fermentation in dairy cows grazed on perennial ryegrass pasture.

PubMed

Ueda, Koichiro; Mitani, Tomohiro; Kondo, Seiji

2016-10-01

Two experiments were conducted to elucidate the effect of increased concentrate allotment before evening grazing on herbage intake, nitrogen utilization and rumen fermentation in dairy cows. In experiment 1, nine lactating cows were grazed in the morning and evening sessions (2.5 h each). The cows were allocated to treatments of three concentrate allotment levels before the evening grazing session by altering proportions to daily total offered; 25%, 50% and 75%. Daily herbage dry matter intake quadratically decreased with increasing the concentrate allotment levels (P < 0.05). Nitrogen utilization was similar among treatments. To investigate diurnal changes in rumen fermentation, a second experiment was conducted where six ruminally cannulated non-lactating dairy cows grazed in the morning and evening sessions (3 h each) were subjected to the same treatments as experiment 1. Total volatile fatty acid concentration in the rumen linearly increased with increasing the concentrate allotment levels throughout the pre-evening grazing session to the post-morning grazing session (P < 0.01). The results indicate that dairy cows reduce daily herbage intake but do not alter nitrogen utilization with increasing concentrate allotment before evening grazing. © 2016 Japanese Society of Animal Science. © 2016 Japanese Society of Animal Science.

Green leaf allowance and dairy ewe performance grazing on tropical pasture.

PubMed

De Souza, J; Batistel, F; Ticiani, E; Sandri, E C; Pedreira, C G S; Oliveira, D E

2014-06-01

pattern in responses to GLA levels as reported in the literature with temperate pastures, the magnitude of the process changed and the maximum response in milk yield from lactating dairy ewes grazing a tropical pasture would be achieved with higher forage allowances than in temperate pastures. Overall, Aruana guineagrass grazed by lactating dairy ewes should be managed to provide 7 to 10 GLA in kg DM/100 kg BW according to the production goals.

Amazing Grazing.

ERIC Educational Resources Information Center

Peterson, Cris

Countless acres of grasslands stretch across the American West. Centuries ago, bison roamed the range freely and lived off the grass. By the 19th century, herds of cattle grazed the same land. Over time, much of the original grassland was either plowed and planted or trampled to dust, causing the topsoil to dry up and blow away. Today many…

Carbon balance of an intensively grazed permanent grassland in southern Belgium

NASA Astrophysics Data System (ADS)

Gourlez de la Motte, Louis; Jérôme, Elisabeth; Mamadou, Ossénatou; Beckers, Yves; Bodson, Bernard; Heineisch, Bernard; Aubinet, Marc

2016-04-01

Grasslands are an important component of the global carbon balance but their carbon storage potential is still highly uncertain. Especially, the impact of weather variability and management practices on grassland carbon budgets need to be assessed. This study investigates the carbon balance of an intensively managed permanent grassland (Dorinne Terrestrial Observatory (DTO)) and its uncertainties by combining 5-years of eddy covariance measurements and other organic carbon exchanges estimates. The specificities of this study lie in: (i) the age of the pasture, which has probably been established since more than one century; (ii) the intensive character of the management with a mean grazing pressure larger than 2 livestock unit ha-1 and stocking cycle including stocking and rest periods, (iii) the livestock production system, typical of Wallonia, farming intensively Belgian Blue breed of cattle in order to produce meat. The results showed that, despite the high stocking rate and the old age of the pasture and the high stocking rate, the site acted as a relatively stable carbon sink from year to year with a 5-year average Net Biome Productivity of ‒173 [‒128 ‒203] g C m-2 yr-1. The carbon sink behavior of the pasture was directly increased by management practices through food complementation and organic fertilization and indirectly by mineral fertilization. The relatively low carbon budget inter-annual variability could be explained both by: (i) grazing management of the farmer that regulated Growth Primary Productivity by adapting the stocking rate to the Leaf Area Index which itself depends on weather conditions, (ii) carbon imports through food complements only when grass regrowth was not sufficient to feed the cattle. The results suggest that management practices that tend to optimize forage availability for meat production could contribute to maintaining a carbon sink. Keywords : grassland, carbon budget, carbon dioxide flux, management, eddy covariance

Greenhouse gas exchange over grazed systems

NASA Astrophysics Data System (ADS)

Felber, R.; Ammann, C.; Neftel, A.

2012-04-01

Grasslands act as sinks and sources of greenhouse gases (GHG) and are, in conjunction with livestock production systems, responsible for a large share of GHG emissions. Whereas ecosystem scale flux measurements (eddy covariance) are commonly used to investigate CO2 exchange (and is becoming state-of-the-art for other GHGs, too), GHG emissions from agricultural animals are usually investigated on the scale of individual animals. Therefore eddy covariance technique has to be tested for combined systems (i.e. grazed systems). Our project investigates the ability of field scale flux measurements to reliably quantify the contribution of grazing dairy cows to the net exchange of CO2 and CH4. To quantify the contribution of the animals to the net flux the position, movement, and grazing/rumination activity of each cow are recorded. In combination with a detailed footprint analysis of the eddy covariance fluxes, the animal related CO2 and CH4 emissions are derived and compared to standard emission values derived from respiration chambers. The aim of the project is to test the assumption whether field scale CO2 flux measurements adequately include the respiration of grazing cows and to identify potential errors in ecosystem Greenhouse gas budgets.

30 CFR 250.260 - What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What Coastal Zone Management Act (CZMA) information must accompany the DPP or DOCD? 250.260 Section 250.260 Mineral Resources MINERALS MANAGEMENT... Operations Coordination Documents (docd) § 250.260 What Coastal Zone Management Act (CZMA) information must...

Animal and pasture responses to grazing management of chemically suppressed tall fescue in mixed pastures

USDA-ARS?s Scientific Manuscript database

Treatment of toxic endophyte-infected tall fescue [Lolium arundinaceum (Schreb.) Darbysh] with metsulfuran-methyl can mitigate fescue toxicosis and enhance forage nutritive value by suppressing seedhead emergence. A grazing experiment was conducted with steers (2013) and heifers (2014) to evaluate a...

Species-abundance--seed-size patterns within a plant community affected by grazing disturbance.

PubMed

Wu, Gao-lin; Shang, Zhan-huan; Zhu, Yuan-jun; Ding, Lu-ming; Wang, Dong

2015-04-01

Seed size has been advanced as a key factor that influences the dynamics of plant communities, but there are few empirical or theoretical predictions of how community dynamics progress based on seed size patterns. Information on the abundance of adults, seedlings, soil seed banks, seed rains, and the seed mass of 96 species was collected in alpine meadows of the Qinghai-Tibetan Plateau (China), which had different levels of grazing disturbance. The relationships between seed-mass-abundance patterns for adults, seedlings, the soil seed bank, and seed rain in the plant community were evaluated using regression models. Results showed that grazing levels affected the relationship between seed size and abundance properties of adult species, seedlings, and the soil seed bank, suggesting that there is a shift in seed-size--species-abundance relationships as a response to the grazing gradient. Grazing had no effect on the pattern of seed-size-seed-rain-abundance at four grazing levels. Grazing also had little effect on the pattern of seed-size--species-abundance and pattern of seed-size--soil-seed-bank-abundance in meadows with no grazing, light grazing, and moderate grazing), but there was a significant negative effect in meadows with heavy grazing. Grazing had little effect on the pattern of seed-size--seedling-abundance with no grazing, but had significant negative effects with light, moderate, and heavy grazing, and the |r| values increased with grazing levels. This indicated that increasing grazing pressure enhanced the advantage of smaller-seeded species in terms of the abundances of adult species, seedlings, and soil seed banks, whereas only the light grazing level promoted the seed rain abundance of larger-seeded species in the plant communities. This study suggests that grazing disturbances are favorable for increasing the species abundance for smaller-seeded species but not for the larger-seeded species in an alpine meadow community. Hence, there is a clear

Herbage intake, methane emissions and animal performance of steers grazing dwarf elephant grass v. dwarf elephant grass and peanut pastures.

PubMed

Andrade, E A; Almeida, E X; Raupp, G T; Miguel, M F; de Liz, D M; Carvalho, P C F; Bayer, C; Ribeiro-Filho, H M N

2016-10-01

Management strategies for increasing ruminant legume consumption and mitigating methane emissions from tropical livestock production systems require further study. The aim of this work was to evaluate the herbage intake, animal performance and enteric methane emissions of cattle grazing dwarf elephant grass (DEG) (Pennisetum purpureum cv. BRS Kurumi) alone or DEG with peanut (Arachis pintoi cv. Amarillo). The experimental treatments were the following: DEG pastures receiving nitrogen fertilization (150 kg N/ha as ammonium nitrate) and DEG intercropped with peanut plus an adjacent area of peanut that was accessible to grazing animals for 5 h/day (from 0700 to 1200 h). The animals grazing legume pastures showed greater average daily gain and herbage intake, and shorter morning and total grazing times. Daily methane emissions were greater from the animals grazing legume pastures, whereas methane emissions per unit of herbage intake did not differ between treatments. Allowing animals access to an exclusive area of legumes in a tropical grass-pasture-based system can improve animal performance without increasing methane production per kg of dry matter intake.

Short communication: grazing pattern of dairy cows that were selected for divergent residual feed intake as calves.

PubMed

Gregorini, P; Waghorn, G C; Kuhn-Sherlock, B; Romera, A J; Macdonald, K A

2015-09-01

The aim of this study was to investigate and assess differences in the grazing pattern of 2 groups of mature dairy cows selected as calves for divergent residual feed intake (RFI). Sixteen Holstein-Friesian cows (471±31kg of body weight, 100 d in milk), comprising 8 cows selected as calves (6-8 mo old) for low (most efficient: CSCLowRFI) and 8 cows selected as calves for high (least efficient: CSCHighRFI) RFI, were used for the purpose of this study. Cows (n=16) were managed as a single group, and strip-grazed (24-h pasture allocation at 0800h) a perennial ryegrass sward for 31 d, with measurements taken during the last 21 d. All cows were equipped with motion sensors for the duration of the study, and jaw movements were measured for three 24-h periods during 3 random nonconsecutive days. Measurements included number of steps and jaw movements during grazing and rumination, plus fecal particle size distribution. Jaw movements were analyzed to identify bites, mastication (oral processing of ingesta) during grazing bouts, chewing during rumination, and to calculate grazing and rumination times for 24-h periods. Grazing and walking behavior were also analyzed in relation to the first meal of the day after the new pasture was allocated. Measured variables were subjected to multivariate analysis. Cows selected for low RFI as calves appeared to (a) prioritize grazing and rumination over idling; (b) take fewer steps, but with a higher proportion of grazing steps at the expense of nongrazing steps; and (c) increase the duration of the first meal and commenced their second meal earlier than CSCHighRFI. The CSCLowRFI had fewer jaw movements during eating (39,820 vs. 45,118 for CSCLowRFI and CSCHighRFI, respectively), more intense rumination (i.e., 5 more chews per bolus), and their feces had 30% less large particles than CSCHighRFI. These results suggest that CSCLowRFI concentrate their grazing activity to the time when fresh pasture is allocated, and graze more efficiently

Solid-state 13C NMR experiments reveal effects of aggregate size on the chemical composition of particulate organic matter in grazed steppe soils

NASA Astrophysics Data System (ADS)

Steffens, M.; Kölbl, A.; Kögel-Knabner, I.

2009-04-01

Grazing is one of the most important factors that may reduce soil organic matter (SOM) stocks and subsequently deteriorate aggregate stability in grassland topsoils. Land use management and grazing reduction are assumed to increase the input of OM, improve the soil aggregation and change species composition of vegetation (changes depth of OM input). Many studies have evaluated the impact of grazing cessation on SOM quantity. But until today little is known about the impact of grazing cessation on the chemical quality of SOM in density fractions, aggregate size classes and different horizons. The central aim of this study was to analyse the quality of SOM fractions in differently sized aggregates and horizons as affected by increased inputs of organic matter due to grazing exclusion. We applied a combined aggregate size, density and particle size fractionation procedure to sandy steppe topsoils with different organic matter inputs due to different grazing intensities (continuously grazed = Cg, winter grazing = Wg, ungrazed since 1999 = Ug99, ungrazed since 1979 = Ug79). Three different particulate organic matter (POM; free POM, in aggregate occluded POM and small in aggregate occluded POM) and seven mineral-associated organic matter fractions were separated for each of three aggregate size classes (coarse = 2000-6300 m, medium = 630-2000 m and fine =

Low-grazing angle laser scans of foreshore topography, swash and inner surf-zone wave heights, and mean water level: validation and storm response

NASA Astrophysics Data System (ADS)

Brodie, K. L.; McNinch, J. E.; Forte, M.; Slocum, R.

2010-12-01

Accurately predicting beach evolution during storms requires models that correctly parameterize wave runup and inner surf-zone processes, the principle drivers of sediment exchange between the beach and surf-zone. Previous studies that aimed at measuring wave runup and swash zone water levels have been restricted to analyzing water-elevation time series of (1) the shoreward-most swash excursion using video imaging or near-bed resistance wires, or (2) the free water surface at a particular location on the foreshore using pressure sensors. These data are often compared with wave forcing parameters in deeper water as well as with beach topography observed at finite intervals throughout the time series to identify links between foreshore evolution, wave spectra, and water level variations. These approaches have lead to numerous parameterizations and empirical equations for wave runup but have difficulty providing adequate data to quantify and understand short-term spatial and temporal variations in foreshore evolution. As a result, modeling shoreline response and changes in sub-aerial beach volume during storms remains a substantial challenge. Here, we demonstrate a novel technique in which a terrestrial laser scanner is used to continuously measure beach and foreshore topography as well as water elevation (and wave height) in the swash and inner surf-zone during storms. The terrestrial laser scanner is mounted 2-m above the dune crest at the Field Research Facility in Duck, NC in line with cross-shore wave gauges located at 2-m, 3-m, 5-m, 6-m, and 8-m of water depth. The laser is automated to collect hourly, two-dimensional, 20-minute time series of data along a narrow swath in addition to an hourly three-dimensional laser scan of beach and dune topography +/- 250m alongshore from the laser. Low grazing-angle laser scans are found to reflect off of the surface of the water, providing spatially (e.g. dx <= 0.1 m) and temporally (e.g. dt = 3Hz) dense elevation data of

Effects of nitrogen deposition and cattle grazing on productivity, invasion impact, and soil microbial processes in a serpentine grassland

NASA Astrophysics Data System (ADS)

Pasari, J.; Hernandez, D.; Selmants, P. C.; Keck, D.

2010-12-01

In recent decades, human activities have vastly increased the amount of biologically available nitrogen (N) in the biosphere. The resulting increase in N availability has broadly affected ecosystems through increased productivity, changes in species composition, altered nutrient cycles, and increases in invasion by exotic plant species, especially in systems that were historically low in N. California serpentine grasslands are N-limited ecosystems historically dominated by native species including several threatened and endangered plants and animals. Cattle grazing has emerged as the primary tool for controlling the impact of nitrophilic exotic grasses whose increased abundance has paralleled the regional traffic-derived increase in atmospheric N deposition. We examined the interactive effects of cattle grazing and N deposition on plant community composition, productivity, invasion resistance, and microbial processes in the Bay Area's largest serpentine grassland to determine the efficacy of current management strategies as well as the biogeochemical consequences of exotic species invasion. In the first two years of the study, aboveground net primary productivity decreased in response to grazing and increased in response to nitrogen addition. However, contrary to our hypotheses the change in productivity was not due to an increase in exotic species cover as there was little overall effect of grazing or N addition on species composition. Microbial activity was more responsive to grazing and N. Potential net N mineralization rates increased with N addition, but were not affected by grazing. In contrast, soil respiration rates were inhibited by grazing, but were not affected by N addition; suggesting strong carbon-limitation of soil microbial activity, particularly under grazing. Site differences in soil depth and grazing intensity were often more important than treatment effects. We suspect that the unusually dry conditions in the first two growing seasons inhibited

The effect of bermudagrass hybrid on forage characteristics, animal performance, and grazing behavior of beef steers.

PubMed

Scaglia, G; Boland, H T

2014-03-01

Bermudagrass (Cynodon dactylon [L.] Pers.) is a major feed source for ruminants across the southeastern United States. In 4 consecutive yr, 3 different bermudagrass hybrids, Alicia, Jiggs, and Tifton-85, were evaluated under a low stocking rate as forage and hay sources. The nutritive value, in situ DM digestibility, and performance and grazing behavior of beef steers under similar management were evaluated. Sampling day had an effect (P < 0.05) on all forage variables. Percentages of CP and TDN decreased while concentration of ADF, NDF, lignin, and nonfiber carbohydrates (NFC) increased as grazing season advanced. Alicia had lower nutritive value, showing greater lignin (5.3%) and indigestible fraction (44.9%) compared to Jiggs (4.9 and 35.6%, respectively) and Tifton-85 (4.5 and 40.1%, respectively). Tifton-85 contained the lowest concentration of NFC (11.8%). Steers grazing Jiggs and Tifton-85 had greater ADG (0.51 and 0.55 kg, respectively) and BW gain per hectare (258 and 279 kg, respectively) than those on Alicia (0.36 kg and 184 kg/ha, respectively); results that are probably explained by the lower nutritive value characteristics of the latter. Most grazing behavior variables were affected (P < 0.05) by time of the day (TOD) and grazing period. Two major grazing events were observed at dawn and dusk. Grazing time (32 min) was lowest (P = 0.003) while standing (140 min) and lying (98 min) time were greater (P = 0.001 and 0.04, respectively) from 1100 to 1559 h, probably as an effect of temperature and humidity at that time of the day. During summer, the temperature humidity index (THI) is above 72 (mild heat load) for the entire season and above 79 (severe heat load) during most of the daylight hours from June to August. Heat load likely affected animal performance and grazing behavior; however, some characteristics associated with these bermudagrass hybrids, especially with Alicia, such as its percentages of lignin and indigestible fraction may also

Commercial timber value of streamside management zones in managed pine and hardwood stands

Treesearch

William A. III Lakel; W. Michael Aust; C. Andrew Dollof; Elizabeth P. Sharp

2005-01-01

Streamside management zones (SMZs) are widely recommended for protection of water quality, but the costs associated with maintaining SMZs are not well documented. This project documented the commercial timber values of 16 watersheds in the Piedmont region and 16 watersheds in the Allegheny Plateau region before and after SMZs were established. Four blocks were...

Commercial timber value of streamside management zones in managed pine and hardwood stands

Treesearch

William A. Lake; W. Michael Aust; C. Andrew Dolloff; Elizabeth P. Sharp

2006-01-01

Streamside management zones (SMZs) are widely recommended for protection of water quality, but the costs associated with maintaining SMZs are not well documented. This project documented the commercial timber values of 16 watersheds in the Piedmont region and 16 watersheds in the Allegheny Plateau region before and after SMZs were established. Four blocks were...

Carrion odor and cattle grazing

PubMed Central

Lev-Yadun, Simcha; Gutman, Mario

2013-01-01

Recently, it has been proposed on theoretical grounds that carrion odor from flowers may not only attract pollinators, but also repel mammalian herbivores. Two grazing experiments involving 16 to 26 cattle heads per year, one for eight years (1982–1989) and the other for seven (1994–2000), in a region with no large carnivores that could influence cattle behavior, show that cattle avoid areas where dead cattle have recently been dumped. They grazed much less in these unfenced plots that were used to dump dead cattle each year. In the first experiment, with an area of ca. 20,000 m2 per head, the average grass biomass at the end of the season was 124.6 gr/m2 for the regular grazing area, whereas it was 236.5 gr/m2 for the carcass dumping area. In the second experiment, with a higher stocking level, with ca. 9,000 m2 per head, the average grass biomass at the end of the season was 61.7 gr/m2 for the regular grazing area, and 153.7 gr/m2 for the carcass dumping area. These significant differences existed throughout the 15 y of the experiments. We propose that these results are clear evidence of necrophobia in cattle, a character that might defend them from both pathogenic microbes and predators. This in turn demonstrates that carrion odor, primarily used by plants to attract pollinators, can simultaneously defend plants from herbivory by mammals as proposed. PMID:25210579

Profitability of grazing versus mechanical forage harvesting on New York dairy farms.

PubMed

Gloy, B A; Tauer, L W; Knoblauch, W

2002-09-01

The profitability of rotational grazing versus mechanical harvesting of forages was estimated using data from 237 nongrazing and 57 grazing farms participating in the New York farm business summary program in the year 2000. The objective was to perform an empirical comparison of the profitability of grazing versus mechanical forage harvesting systems. A regression analysis technique that controls for treatment selection bias is used to determine the impact of grazing on the rate of return on assets. This is accomplished by joint maximum likelihood estimation of a probit adoption function and a profit function. The results indicate that treatment selection does not have an important impact on the estimate of the profitability of grazing. There were wide ranges and overlap of profitability among herds using the two systems. However, other things equal, farmers utilizing grazing systems were at least if not more profitable than farmers not using grazing systems. After controlling for the factors influencing the decision to graze, we found that herd size, rate of milk production per cow, and prices received for milk have a strong positive impact on profitability. Farmers who perceive potential lifestyle benefits that might be obtained by implementing a grazing system likely do not have to pay an income penalty for adopting a grazing system.

25 CFR 166.308 - Can the number of animals and/or season of use be modified on the permitted land if I graze...

Code of Federal Regulations, 2013 CFR

2013-04-01

... 25 Indians 1 2013-04-01 2013-04-01 false Can the number of animals and/or season of use be... AND WATER GRAZING PERMITS Land and Operations Management § 166.308 Can the number of animals and/or... an on-and-off grazing permit? Yes. The number of animals and/or season of use may be modified on...

25 CFR 166.308 - Can the number of animals and/or season of use be modified on the permitted land if I graze...

Code of Federal Regulations, 2012 CFR

2012-04-01

... 25 Indians 1 2012-04-01 2011-04-01 true Can the number of animals and/or season of use be modified... WATER GRAZING PERMITS Land and Operations Management § 166.308 Can the number of animals and/or season... on-and-off grazing permit? Yes. The number of animals and/or season of use may be modified on...

25 CFR 166.308 - Can the number of animals and/or season of use be modified on the permitted land if I graze...

Code of Federal Regulations, 2011 CFR

2011-04-01

... 25 Indians 1 2011-04-01 2011-04-01 false Can the number of animals and/or season of use be... AND WATER GRAZING PERMITS Land and Operations Management § 166.308 Can the number of animals and/or... an on-and-off grazing permit? Yes. The number of animals and/or season of use may be modified on...

25 CFR 166.308 - Can the number of animals and/or season of use be modified on the permitted land if I graze...

Code of Federal Regulations, 2010 CFR

2010-04-01

... 25 Indians 1 2010-04-01 2010-04-01 false Can the number of animals and/or season of use be... AND WATER GRAZING PERMITS Land and Operations Management § 166.308 Can the number of animals and/or... an on-and-off grazing permit? Yes. The number of animals and/or season of use may be modified on...

25 CFR 166.308 - Can the number of animals and/or season of use be modified on the permitted land if I graze...

Code of Federal Regulations, 2014 CFR

2014-04-01

... 25 Indians 1 2014-04-01 2014-04-01 false Can the number of animals and/or season of use be... AND WATER GRAZING PERMITS Land and Operations Management § 166.308 Can the number of animals and/or... an on-and-off grazing permit? Yes. The number of animals and/or season of use may be modified on...

36 CFR 251.103 - Mediation of term grazing permit disputes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Mediation of term grazing... Lands § 251.103 Mediation of term grazing permit disputes. (a) Decisions subject to mediation. In those States with Department of Agriculture certified mediation programs, any holder of a term grazing permit...

Milk yield and somatic cell score of northeastern United States organic dairy farms during the grazing and non-grazing seasons

USDA-ARS?s Scientific Manuscript database

The objective of this study was to evaluate milk yield and composition of organically-certified dairy herds during grazing season (GS) and non-grazing season (NGS) in the Northeast region of the United States. Dairy Herd Improvement records of Holstein, Jersey, and Holstein-Jersey crossbred cows fro...

Grazing winter rye cover crop in a cotton no-till system: yield and economics

USDA-ARS?s Scientific Manuscript database

Winter cover crop adoption in conservation management systems continues to be limited in the US but could be encouraged if establishment costs could be offset. A 4-yr field experiment was conducted near Watkinsville, Georgia in which a rye (Secale cereale L.) cover crop was either grazed by catt...

Disentangling niche competition from grazing mortality in phytoplankton dilution experiments

PubMed Central

Weitz, Joshua S.

2017-01-01

The dilution method is the principal tool used to infer in situ microzooplankton grazing rates. However, grazing is the only mortality process considered in the theoretical model underlying the interpretation of dilution method experiments. Here we evaluate the robustness of mortality estimates inferred from dilution experiments when there is concurrent niche competition amongst phytoplankton. Using a combination of mathematical analysis and numerical simulations, we find that grazing rates may be overestimated—the degree of overestimation is related to the importance of niche competition relative to microzooplankton grazing. In response, we propose a conceptual method to disentangle the effects of niche competition and grazing by diluting out microzooplankton, but not phytoplankton. Our theoretical results suggest this revised “Z-dilution” method can robustly infer grazing mortality, regardless of the dominant phytoplankton mortality driver in our system. Further, we show it is possible to independently estimate both grazing mortality and niche competition if the classical and Z-dilution methods can be used in tandem. We discuss the significance of these results for quantifying phytoplankton mortality rates; and the feasibility of implementing the Z-dilution method in practice, whether in model systems or in complex communities with overlap in the size distributions of phytoplankton and microzooplankton. PMID:28505212

Implementing Rotational Partial Rest/Patch-Burn Grazing in the Flint Hills, Kansas

DTIC Science & Technology

2008-09-30

recently published a paper about the project in Ecological Restoration, titled Managing for Grassland Diversity: A Study on Grazing-Fire Interactions in...Eagle, print and online editions July 2008 From Beef to Butterflies: Enhancing Diversity in the Tallgrass Prairie Plants & Pollinators Symposium...Wolfe, E. Shochat, and S.K. Sherrod. 2005. Habitat fragmentation, rapid evolution and population persistence. Evolutionary Ecology Research 7: 235-249

Responses of microbial respiration in grazed and ungrazed grasslands to glucose addition

NASA Astrophysics Data System (ADS)

Xu, Xingliang; Liu, Qianyuan; Pang, Rui

2017-04-01

Grazing can change species composition, alter soil properties, and thus modify microbial activities, affecting biogeochemical processes in grasslands. However, it remains unclear how microbial respiration in grazed and ungrazed grasslands responds to glucose addition. Here we hypothesize that microbial respiration in grazed grasslands will respond more strongly to glucose addition than in ungrazed grasslands because moderate grazing can enhance microbial activity. To examine the hypothesis above, we collected the upper 10 cm soil from grazed and ungrazed grasslands at five sites of China. Three sites (Hulunbuir 1, Hulunbuir 2 and Xielingele) were located in Inner Mongolia and two in the Tibet Plateau) Soils were incubated with low glucose input (50% MBC), high glucose input (150% MBC), and water for 60 days in 21oC. CO2 released from soil was trapped with 1 M NaOH. The results showed that the effect of grazing on microbial respiration has two distinct patterns, depending on soil types and addition amount. After glucose addition, cumulative CO2 efflux from grazed soils was significantly higher than from ungrazed soils in two temperate grasslands (Hulunbuir 1 and Xielingele). This may be ascribed to that moderate grazing promoted microbial activity. On the contrary, microbial respirations from grazed soils were lower than ungrazed soils in two alpine meadows of Haibei and Dangxiong and in Hulunbuir 2. This effect of grazing was not obvious in Hulunbeier 2 soils at low carbon addition level. Grazing may decrease soil organic carbon, nitrogen availability and thus microbial activity in alpine grasslands. These findings indicate that soil microorganisms could have different adaptation mechanisms to grazing in temperate and alpine grasslands.

Hydrology and grazing jointly control a large-river food web.

PubMed

Strayer, David L; Pace, Michael L; Caraco, Nina F; Cole, Jonathan J; Findlay, Stuart E G

2008-01-01

Inputs of fresh water and grazing both can control aquatic food webs, but little is known about the relative strengths of and interactions between these controls. We use long-term data on the food web of the freshwater Hudson River estuary to investigate the importance of, and interactions between, inputs of fresh water and grazing by the invasive zebra mussel (Dreissena polymorpha). Both freshwater inputs and zebra mussel grazing have strong, pervasive effects on the Hudson River food web. High flow tended to reduce population size in most parts of the food web. High grazing also reduced populations in the planktonic food web, but increased populations in the littoral food web, probably as a result of increases in water clarity. The influences of flow and zebra mussel grazing were roughly equal (i.e., within a factor of 2) for many variables over the period of our study. Zebra mussel grazing made phytoplankton less sensitive to freshwater inputs, but water clarity and the littoral food web more sensitive to freshwater inputs, showing that interactions between these two controlling factors can be strong and varied.

Influence of elk grazing on soil properties in Rocky Mountain National Park

USGS Publications Warehouse

Binkley, Dan; Singer, F.; Kaye, M.; Rochelle, R.

2003-01-01

We used three 35-year exclosures to examine the effects of high elk populations on a variety of soil properties in three vegetation types: upland sagebrush, aspen, and meadow. Grazing and hoof action by elk significantly increased bulk density (from 0.87 kg/l ungrazed to 0.94 kg/l grazed), with greater effects on soils with fewer rocks. Grazing substantially reduced extractable calcium, magnesium, potassium and phosphorus in the sagebrush type, but not in the aspen or meadow types. The only grazing effect on pH came in aspen types, where grazing prevented aspen establishment, and kept soil pH about 0.7 units higher than under aspen inside the exclosures. Grazing had no overall effect on total soil C and N across all exclosures and vegetation types. The availability of soil nitrogen, indexed by in-field resin bags and net mineralization in soil cores, showed little overall effect of grazing. Limited data on soil leaching indicated a possibility of strong increases in nitrate leaching with grazing for an aspen vegetation type at one exclosure. Although we found little effect of grazing on soil N supply, we note that N fertilization doubled the production of grasses and shrubs; if grazing eventually led to changes in soil N supply, species composition and growth would likely change. ?? 2003 Elsevier B.V. All rights reserved.

Reconsidering rest following fire: Northern mixed-grass prairie is resilient to grazing following spring wildfire

USDA-ARS?s Scientific Manuscript database

Current federal post-fire land management recommendations in the United States suggest that rangelands be rested from grazing for two growing seasons following fire to allow for proper recovery, despite the lack of empirical literature supporting this recommendation. This project was designed to de...

Importance of early season conditions and grazing on carbon dioxide fluxes in Colorado shortgrass steppe

USDA-ARS?s Scientific Manuscript database

Understanding the influence of environmental and management drivers on fluxes of carbon dioxide (CO2) is essential for optimizing carbon (C) uptake and storage in livestock production systems. Herein, using 15 treatment-years (two three-year experiments, one with three grazing treatments, the other ...

Grazing effect on woody plant recruitment in a Sonoran Desert grassland across space and time

USDA-ARS?s Scientific Manuscript database

Livestock grazing is a commonly cited factor contributing to shrub encroachment in savannas and grasslands. Patterns of woody plant proliferation are known to influence rates of erosion and spread of disturbance and are of practical importance to livestock management with regard to forage distribut...

Effects of rotational and continuous grazing on herbage quality, feed intake and performance of sheep on a semi-arid grassland steppe.

PubMed

Hao, Jun; Dickhoefer, Uta; Lin, Lijun; Müller, Katrin; Glindemann, Thomas; Schönbach, Philipp; Schiborra, Anne; Wang, Chengjie; Susenbeth, Andreas

2013-02-01

Compared to continuous grazing (CG), rotational grazing (RG) increases herbage production and thereby the resilience of grasslands to intensive grazing. Results on feed intake and animal performance, however, are contradictory. Hence, the objective of the study was to determine the effects of RG and CG on herbage mass, digestibility of ingested organic matter (dOM), organic matter intake (OMI) and live weight gain (LWG) of sheep in the Inner Mongolian steppe, China. During June-September 2005-2008, two 2-ha plots were used for each grazing system. In RG, plots were divided into four 0.5-ha paddocks that were grazed for 10 days each at a moderate stocking rate. Instead, CG sheep grazed the whole plots throughout the entire grazing season. At the beginning of every month, dOM was estimated from faecal crude protein concentration. Faeces excretion was determined using titanium dioxide in six sheep per plot. The animals were weighed every month to determine their LWG. Across the years, herbage mass did not differ between systems (p = 0.820). However, dOM, OMI and LWG were lower in RG than in CG (p ≤ 0.005). Thus, our study showed that RG does not improve herbage growth, feed intake and performance of sheep and suggests that stocking rates rather than management system determine the ecological sustainability of pastoral livestock systems in semi-arid environments.

Effect of alternate and simultaneous grazing on endoparasite infection in sheep and cattle.

PubMed

Brito, Daiana Lima; Dallago, Bruno Stéfano Lima; Louvandini, Helder; dos Santos, Viviane Rodrigues Verdolin; Torres, Sonia Emília Figueirêdo de Araújo; Gomes, Edgard Franco; do Amarante, Alessandro Francisco Talamini; de Melo, Cristiano Barros; McManus, Concepta Margaret

2013-01-01

This experiment was carried out on 8 ha of Panicum maximum cv. Tanzania pastures, with rotational grazing consisting of 7 days of occupation and 21 days of rest. Four treatments were evaluated: cattle grazing alone (BOV), sheep grazing alone (OVI), cattle and sheep grazing simultaneously (SIM) and cattle grazing followed by sheep (alternate - ALT). Twenty heifers and 30 male Santa Inês lambs were used. Fecal egg count (FEC) and fecal cultures were carried out. Blood was also collected to examine red and white cell series, total plasma protein (TPP), albumin and hemoglobin. FEC and estimated nematode pathogenicity index in sheep were lower in the SIM treatment. The Haemonchus spp. proportion was higher in isolated grazing systems. For sheep, mixed grazing was shown to reduce endoparasite infection, and SIM was better than ALT. For cattle, no difference between grazing systems was seen. Therefore, simultaneous grazing (sheep and cattle) may be a tool for reducing the need for anthelmintic treatments in sheep.

Vertebrate herbivory in managed coastal wetlands: A manipulative experiment

USGS Publications Warehouse

Johnson, L.A.; Foote, A.L.

1997-01-01

Structural marsh management and nutria herbivory are both believed to strongly influence plant production in the brackish, deltaic marshes of coastal Louisiana, USA. Previous studies have tested the effects of structural management on aboveground biomass after implementing management, but very few studies have collected data before and after management. Thus, to test the effects of structural marsh management on Spartina patens (Ait.) Muhl. and Scirpus americanus Pers., the aboveground biomass of both species was estimated before and after the construction of shallow, leveed impoundments. The water level in each impoundment was managed with a single flap-gated culvert fitted with a variable crest weir. Additionally, the influence of nutria grazing on aboveground biomass was measured by nondestructively sampling fenced (ungrazed) and unfenced (grazed) plots in both managed and unmanaged areas. While there was no significant difference in S. patens production between managed and unmanaged areas, marsh management negatively affected Sc. americanus production the two species also differed in their responses to grazing. Grazing dramatically reduced the sedge, Sc. americanus, while the grass, S. patens, remained at similar biomass levels in grazed and ungrazed plant stands. These findings support the belief that herbivory has a strong influence on plant production, but do not support the claim that management increases plant production in the deltaic marshes of Louisiana.

Targeted livestock grazing to improve and restore rangelands

USDA-ARS?s Scientific Manuscript database

Targeted grazing is the application of a specific kind of livestock at the appropriate season, duration, and intensity to accomplish defined vegetation or landscape goals. Grazing by wild and domestic animals is a powerful natural force working in all ecosystems. The ability of selective herbivory t...

Critical Zone Services as a Measure for Evaluating the Trade-offs in Intensively Managed Landscapes

NASA Astrophysics Data System (ADS)

Richardson, M.; Kumar, P.

2015-12-01

The Critical Zone includes the range of biophysical processes occurring from the top of the vegetation canopy to the weathering zone below the groundwater table. These services (Field et al. 2015) provide a measure to value processes that support the goods and services from our landscapes. In intensively managed landscapes the provisioning and regulating services are being altered through anthropogenic energy inputs so as to derive more agricultural productivity from the landscapes. Land use change and other alterations to the environment result in positive and/or negative net Critical Zone services. Through studies in the Critical Zone Observatory for Intensively Managed Landscapes (IMLCZO), this research seeks to answer questions such as: Are perennial bioenergy crops or annual replaced crops better for the land and surrounding environment? How do we evaluate the products and services from the land for the energy and resources we put in? Before the economic valuation of Critical Zone services, these questions seemed abstract. However, with developments such as Critical Zone services and life cycle assessments, they are more concrete. To evaluate the trade-offs between positive and negative impacts, life cycle assessments are used to create an inventory of all the energy inputs and outputs in a landscape management system. Total energy is computed by summing the mechanical energy used to construct tile drains, fertilizer, and other processes involved in intensely managed landscapes and the chemical energy gained by the production of biofuels from bioenergy crops. A multi-layer canopy model (MLCan) computes soil, water, and nutrient outputs for each crop type, which can be translated into Critical Zone services. These values are then viewed alongside the energy inputs into the system to show the relationship between agricultural practices and their corresponding ecosystem and environmental impacts.

Willow establishment in relation to cattle grazing on an eastern Oregon stream

Treesearch

Nancy L. Shaw; Warren P. Clary

1996-01-01

Natural regeneration and growth of coyote willow (Salix exigua Nutt. ssp. exigua) and whiplash willow (S. lasiandra Bemth. var. caudata [Nutt.] Sudw.) were monitored from 1987 to 1993 on a low-elevation eastern Oregon stream degraded by more than a century of heavy livestock grazing. Treatments were no grazing, moderate spring grazing, moderate fall grazing, and...