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Scientifically advanced woody media for improved water quality from livestock woodchip heavy-use areas

Frontiers of Environmental Science & Engineering 2017年第3期11卷 35-43页

作者： Laura Christianson David DeVallance Joshua Faulkner Thomas Basden Crop Sciences University of Illinois Urbana IL 61801 USA Wood Science and Technology West Virginia University Morgantown WV 26506 USA university of Vermont extension UVM Center for Sustainable Agriculture Burlington VT 05401 USA west virginia university extension West Virginia University Morgantown WV 26506 USA

Overwintering cattle on pastures in many areas can damage the pasture and lead to impaired water quality. During these times, use ofa woodchip heavy-use area （HUA） presents advantages such as a soft, supportive, and dry toot surface for animals and protection of the pasture and pasture soils. However, woodchip HUAs can also be a centralized source of high nutrient loads due to their drainage outflows. A column study was conducted to assess the nutrient load reduction potential of： 1 ） six types of wood media （including torrefied wood media and biochar） that could be used in a woodchip HUA versus a gravel control, and 2） providing a 48 h retention time within the wood media to enhance nitrogen removal through denitrification. The woody media provided significant liquid waste volume reduction compared to the gravel in simulated events （53%-61% vs. 39% reductions, respectively）, and there may be additional liquid storage capacity in the woodchips not utilized during these rapid events. Substantial total nitrogen removal by the wood treatments （mean removal efficiencies 〉 50%） was observed across the sinmlated events, although nitrate leaching also occurred. Nitrate removal was enhanced during the 48 h retention test which showed removal was governed by availability of labile carbon （i.e., fresh woodchips exhibited 〉 70% nitrate removal）. The retention test also indicated biochar mixtures provided some of the best total phosphorus removal, but the greatest benefits across all parameters was provided by the Mixed Hardwood treatment.

关键词： Overwinter Heavy-use area Nutrient pollution Torrefied Woodchip

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Adaptive economic and ecological forest management under risk

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Forest Ecosystems 2015年第2期2卷 67-81页

作者： Joseph Buongiorno Mo Zhou university of Wisconsin-Madison west virginia university

Background： Forest managers must deal with inherently stochastic ecological and economic processes. The future growth of trees is uncertain, and so is their value. The randomness of low-impact, high frequency or rare catastrophic shocks in forest growth has significant implications in shaping the mix of tree species and the forest landscape. In addition, the fluctuations of wood prices influence greatly forest revenues. Methods： Markov decision process models （MDPs） offer a rigorous and practical way of developing optimum management strategies, given these multiple sources of risk. Results： Examples illustrate how such management guidelines are obtained with MDPs for combined ecological and economic objectives, including diversity of tree species and size, landscape diversity, old growth preservation, and carbon sequestration. Conclusions： The findings illustrate the power of the MDP approach to deal with risk in forest resource management. They recognize that the future is best viewed in terms of probabilities. Given these probabilities, MDPs tie optimum adaptive actions strictly to the state of the forest and timber prices at decision time. The methods are theoretically rigorous, numerically efficient, and practical for field implementation.

关键词： Risk Management Economics Ecology Markov Optimization

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Responses of early-successional songbirds to a two-stage shelterwood harvest for oak forest regeneration

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Avian Research 2018年第3期9卷 253-263页

作者： Eric L.Margenau Yong Wang Callie J.Schweitzer BrANDie K.Stringer Department of Biological and Environmental Sciences Alabama A&M University west virginia Cooperative Fish and Wildlife Research Unit School of Natural Resources West Virginia University Southern Research Station United States Forest Service

Background: The early stage of forest succession following disturbance is characterized by a shift in songbird composition as well as increased avian richness due to increased herbaceous growth in the forest understory. However, regeneration of woody species eventually outcompetes the herbaceous understory, subsequently shifting vegetation communities and decreasing availability of vital foraging and nesting cover for disturbance-dependent birds, ultimately resulting in their displacement. These early stages following forest disturbance, which are declining throughout the eastern United States, are ephemeral in nature and birds depend on such disturbances for nesting and other purposes throughout their ***: We investigated the use of a two-stage shelterwood method to manage long-term persistence of seven early successional songbirds over a 13-year period in an upland hardwood forest within the southern end of the midCumberland Plateau in the eastern United ***: Canopy and midstory gaps created after initial harvest were quickly exploited by tree growth and canopy cover returned to these areas, accelerating the displacement of early-successional species. Woody stem densities increased substantially following stage two harvest as advanced tree regeneration combined with the re-opening of the overstory layer increased resource competition for early-successional plants in the understory. Carolina Wren(Thryothorus ludovicianus), Eastern Towhee(Pipilo erythrophthalmus), Indigo Bunting(Passerina cyanea), and Yellowbreasted Chat(Icteria virens) were characterized by immediate increases following initial harvest in 2001; while the American Goldfinch(Spinus tristis), Prairie Warbler(Setophaga discolor), and White-eyed Vireo(Vireo griseus) did not show an immediate response. Stage two harvest in 2011 rejuvenated vegetation which benefitted focal species, with six of seven species showing increases in densities between 2010 and ***: The two-stag

关键词： Early-successional forests Mid-Cumberland Plateau Silviculture Shelterwood Songbird community

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Evaluation of forage-based weaning systems in spring-born cross-bred beef calves

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Open Journal of Animal Sciences 2013年第2期3卷 99-104页

作者： John Fredrick Odhiambo Robert Arthur Dailey Ronnie Helmondollar James Yeager Pritchard Phillip Irvin Osborne Division of Animal and Nutritional Sciences West Virginia University Morgantown USA west virginia university extension service Randolph County Extension Office Elkins USA

Preconditioned calves have greater marketvalue per unit weight than normal-weaned calves. Development of a low cost forage-based preconditioning system allows producers to add value to their calf-crop. This study evaluated calf performance in three forage-based weaning systems;early-weaned calves were backgrounded in legume/grass forage plots and supplemented with commercial preconditioning feed (Treatment 1) or an on-farm corn-mix (Treatment 2). Control (Treatment 3) calves suckled for an additional 45 days. Supplements provided2.17 kgTDN/calf/ day. Weights were collected on days -30, 0 and 45 with respect to early weaning, from135 inyear 1 and 150 calves in each of the two subsequent years. Effects of treatment, age of dam, sex of calf and their interactions on calf weight gain were analyzed by analysis of covariance using GLM procedures of SAS. Marginal effects of treatment and feed cost were used to evaluate economic feasibility. Sensitivity analyses were evaluated for anticipated market fluctuations in feed costs and calf premiums. Data are reported as least squares means. Calf weight gains differed (P < 0.001) among treatments and averaged 1.16, 1.03 and1.04 kg/calf/day for commercial supplement, corn-mix and controls, respectively. Calves from 2-year-old cows gained less (P < 0.001) weight compared to those from cows 3 - 4 and ≥5 years of age (44.8, 48.9 and51.5 kg, respectively). Steers calves gained more (P < 0.001) weight compared to heifer calves (51.2 vs.45.7 kg, respectively). Net returns for corn mix were greater than those for commercial feed ($1.48 vs. $1.35/kg weight gain, respectively). Sensitivity analyses indicated that selection of preconditioning treatment to a large degree was less sensitive to significant changes in market conditions due to the large gap in marginal costs between the two treatments. In conclusion, forage-based weaning systems can be utilized to precondition calves providing an economical means for calf weight gain and profit

关键词： Preconditioning Beef Calves Early Weaning Weight Gain

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Morphological and Biochemical Changes in Ginseng Seedling Roots Affected with Stripe Symptoms

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American Journal of Plant Sciences 2015年第16期6卷 2550-2560页

作者： Zamir K. Punja Mahfuzur Rahman Department of Biological Sciences Simon Fraser University Burnaby Canada WVU extension service West Virginia University Morgantown USA

A unique symptom of longitudinal red stripes on the surface of one-year-old ginseng roots was studied to determine the morphological and biochemical changes taking place. Light and scanning electron microscopy, measurements of phenolic and mineral element content, and enzyme activity, were compared between healthy and stripe-affected root tissues. Light microscopy revealed that the root epidermis had ruptured and fissures extended for 3 - 4 cell layers into the cortex. Phenolic compounds accumulated in the epidermal cells which stained with Toluidine blue 0. Total phenolic content was higher in tissues from striped roots compared to healthy roots and HPLC profiles showed increases in a number of specific phenolic compounds. Analysis of epidermal tissues by SEM-EDX for mineral element content showed a marked increase in levels of iron, silicon and aluminum and a decline in potassium in striped root tissues. The activity of the enzymes phenylalanine ammonia lyase and peroxidase were also found to be higher in striped root tissues. Striping of ginseng roots is a physiological condition caused by a rupture of the epidermis due to rapid growth of underlying cells, which results in phenolic accumulation and sequestration of several minerals. Further oxidation causes a visible red striping on the root surface.

关键词： Cell Disruption Iron Sequestration Panax quinquefolius Phenolics Root Epidermis

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CRITICAL ISSUES OF POWDER METALLURGY TURBINE DISKS

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Acta Metallurgica Sinica(English Letters) 1996年第6期9卷 467-471页

作者： K.M. Chang(Department of Mechanical and Aerospace Engineering,west virginia university, P.O. Box 6160, Morgantown,WV 26506, USA west virginia Univ Morgantown United States

P/M superalloy disks obtain their final strength by appropriate heat treatments; the maximum attainable strength depends on the rapid cooling rate from the solution annealing. A rapid quench of a large disk forging can cause two problems, surface cracking and shape *** the past,many attempts employ the finite element code to model and to predict temperature evolution and induced stress distribution in a large turbine disk. The major difficulty was the correct description of alloy behavior; particularly the thermomechanical properties and the failure criteria of material during the cooling. High temperature fatigue resistance is always the key requirement for disk materials. New methodology of residual life management emphasizes the initiation as well as the propagation of the cracks developed under the service conditions. One of major challenges to P/M superalloys is the time-dependent behavior of fatigue cracking, which relates to the well-known SAGBO (stress-assisted grain boundary oxidation) phenomenon.A great effort has been done to understand the micro-mechanism of time-dependent fatigue crack propagation resulted in the second generation of P/M superalloys. Further improvement on temperature capability of disk alloys at rim area may lead to the idea of dual-property *** grain structures at different portions of a large disk are possible,as the property requirements for different locations are different. This goal is achievable if the thermal history at specific disk locations can be controlled to develop desirable microstructures and *** suggestions on the future direction of research efforts will be discused.

关键词： superalloy disk,powder metallurgy (P/M) quench cracking,fatigue crack propagation SAGBO (stress-assisted grain boundary oxidation),dual-property disk grain size

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Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves

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Journal of Animal Science and Biotechnology 2012年第4期3卷 221-226页

作者： Stacey A Gunter Whitney A Whitworth T Gregory Montgomery Paul A Beck United States Department of Agriculture Agricultural Research Service Southern Plains Range Research Station university of Arkansas at Monticello Division of Agriculture Southeast Research & Extension Center University of Arkansas Division of Agriculture Southwest Research & Extension Center University of Arkansas

In December of 3 years, 87 beef cows with nursing calves （.594 ± 9.8 kg; calving season, September to November） at side were stratified by body condition score, body weight, cow age, and calf gender and divided randomly into 6 groups assigned to 1 of 6 cool-season annual pastures （0.45 ha/cow） that had been interseeded into a dormant common bermudagrass （Cynodon dactylon [L.] Pers.）/bahiagrass （Paspalum notatum Flugge） sod. Pastures contained 1 of the following 3 seeding mixtures （2 pastures/mixture）： 1） wheat （Triticum aestivurn L.） and ryegrass （Lofium multiflorum Lain., WRG）, 2） wheat and ryegrass plus red clover （Trifolium pretense L, WRR）, or 3） wheat and ryegrass plus white （Trifofium repens L.） and crimson clovers （Trifolium incarnatum L., WRW）. All groups had ad libitum access to grass hay （12% crude protein; 58% total digestible nutrients）. The second week in December, cow estrous cycles were synchronized and artificially inseminated. In late December, a bull was placed with each group for 60-d. Data were analyzed with an analysis of variance using a mixed model containing treatment as the fixed effect and year as the random effect. Body weight and condition scores did not differ （P ≥ 0.27） among cows between February and June. Calf birth weights or average daily gain did not differ （P≥ 0.17） among treatments; however, calves grazing pastures with clovers did tend （P= 0.06） to weigh more than calves grazing grass only. Weaning weight per cow exposed to a bull was greater （P= 0.02） for WRR and WRW than WRG. Cows grazing winter-annual pastures containing clovers tended to wean more calf body weight per cow exposed to a bull than cows grazing the grass only pastures.

关键词： Annual ryegrass Beef cows Clovers Nitrogen Pasture 1

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Developing a Historical Phenology Dataset through Community Involvement for Climate Change Research

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American Journal of Climate Change 2020年第1期9卷 11-22页

作者： Lori Petrauski Sheldon Owen George Constantz James T. Anderson Division of Forestry and Natural Resources West Virginia University Morgantown WV USA west virginia university extension service Morgantown WV USA 818 Great Plains Dr. Capon Bridge WV USA

There has been an increased effort to utilize untapped sources of historical phenological data such as museum specimens, journals written by nature-minded citizens, and dated photographs through local phenology projects for climate change research. Local phenology projects have contributed greatly to our current understanding of phenological changes over time and have an important role in the public’s engagement with natural history, but there are also significant challenges in finding and analyzing historical data. The west virginia Climate History Project collected historical phenology data (1890-2015) from citizens in west virginia with scientific and cultural results. We discuss the development of the project, issues we overcame, recommendations for future projects, and the conservation value of local phenology projects. Local phenology projects lend value to climate change research and conservation education. Policy directed towards supporting humanities grants and museum collections, including herbariums, is crucial in the success of these projects.

关键词： Historical Phenology Community Phenology Citizen Science Conservation Phenology

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Integrated pest management concepts for red imported fire ants Solenopsis invicta （Hymenoptera： Formicidae）

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Insect Science 2013年第4期20卷 429-438页

作者： Bastiaan M. Drees Alejandro A. Calixto Paul R. Nester Texas AgriLife extension service Texas A&M System Mail Stop 2475 Department of Entomology College Station TX 77843-2475 Dew AgroSciences CPRD Wesley Chapel FL 33543 Harris Co. Texas AgriLife Extension Service Texas A&M University System TXUSA

Management of imported fire ant species has evolved since their accidental introduction into the United States and currently uses integrated pest management concepts to design, implement, and evaluate suppression programs. Although eradication is the management goal in certain isolated infestation sites, localized goals vary dramatically in larger infestations where reinvasion of treated areas is likely. These goals are influenced by regulatory policies, medical liabilities, ecological impact, and/or economic considerations. Tactics employed in fire ant management programs presented here include cultural and biological control options along with judicious use of site-specific insecticide products. In addition, program design considerations that include management goal（s）, action level（s）, ant form （monogyne or polygyne）, presence ofnontarget ant species, size of treatment area, seasonality, implementation cost, and environmental impact are also presented. Optimally, elegant IPM programs are target specific, threshold driven, environmentally friendly and cost-effective.

关键词： imported fire ants integrated pest management IPM concepts Solenopsisinvicta Solenopsis richteri

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FATIGUE CRACK PROPAGATION OF Ni-BASE SUPERALLOYS

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Acta Metallurgica Sinica(English Letters) 2005年第1期18卷 55-64页

作者： E.Barbero Dept. of Mechanical & Aerospace Engineering West Virginia University Morgantown WV 26506-6106 USA

Time-dependent Fatigue Crack Propagation (FCP) behaviors of five Ni-base superalloys were investigated at various temperatures under fatigue with various holding times and sustained loading conditions. The new concept of damage zone is defined and employed to evaluate the alloys' resistance to hold-time FCP. A special testing procedure is designed to get the maximum damage zone of the alloys. Udimet 720 and Waspaloy show shorter damage zones than alloys 706 and 718. The fractographical analyses show that the fracture surfaces of the specimens under hold-time fatigue conditions are mixtures with intergranular and transgranular modes. As the extension of holding time per cycle, the portion of intergranular fracture increases, The effects of loading stress intensity, temperature, holding time, alloy chemistry, and alloy mi-crostructure on damage zone and the crack growth behaviors are studied. Hold-time usually increases the alloy's FCP rate, but there are few exemptions. For instance, the steady state hold-time FCP rate of Waspaloy at 760℃ is lower than that without hold-time. The beneficial effect of hold-time was attributed to the creep caused stress relaxation during the hold-time.

关键词： Ni-base superalloys fatigue crack growth hold-time

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