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Selection of overburden surface mining method in West virginia by analytical hierarchy process

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International Journal of Coal Science & Technology 2014年第3期1卷 306-314页

作者： Timothy A.Nolan Vladislav Kecojevic Department of Mining Engineering West Virginia UniversityMorgantownWVUSA

The broad objective of this research was to improve current surface mining practices and reduce negative environmental impact of overburden removal in West virginia(WV).The specific objectives were to(i)compare conventional surface mining method(drilling,blasting,digging,and loading)to a surface miner(SM)method,and(ii)apply the analytical hierarchy process(AHP)to help select the optimal mining method based on production,cost and environmental *** design and the procedures used in this research involve five interrelated modules:(i)rock properties of overburden in WV,(ii)drilling and blasting,(iii)digging and loading,(iv)SM method,and(v)comparative analysis and selection of the optimal mining method by *** of this research indicate that application of SM method would yield higher cost of overburden removal than conventional mining methods in rocks with a high unconfined compressive strength and abrasivity.A significant advantage of SM method,where applicable,is the elimination of the negative environmental impacts associated with blasting.

关键词： Surface mining West virginia Overburden Production rate Cost Environmental impact AHP model

Effects of historic wildfire and prescribed fire on site occupancy of bats in Shenandoah National Park,virginia,USA

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Journal of Forestry Research 2020年第4期31卷 1255-1270页

作者： Lauren V.Austin Alexander Silvis W.Mark Ford Karen E.Powers Department of Fish and Wildlife Conservation Virginia TechBlacksburgVA 24061USA Resource Environmental Solutions WarrentonVA 20187USA U.S.Geological Survey Virginia Cooperative Fish and Wildlife Research UnitBlacksburgVA 24061USA Biology Department Radford UniversityRadfordVA 24141USA

Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome,it is critical that the impacts of forest management activities,such as prescribed fire,are known in order to minimize potentially additive negative effects on bat *** wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning,implementing and assessing burn *** examine the effects of historic fire on bats,we sampled bat activities at 24 transect locations in burned and unburned forest stands in the central Appalachian Mountains of Shenandoah National Park(SNP),virginia,*** was limited evidence of positive fire effects over time on hoary bats(Lasiurus cinereus Beauvois)and big brown bats(Eptesicus fuscus Beauvois)***,there were few or mostly equivocal relationships of bat occupancy relative to burn conditions or time since fire in SNP across species using a false-positive occupancy *** results suggest that fire does not strongly affect bat site occupancy short-or long-term in the central Appalachians.

关键词： Appalachian mountains Bats False-positive occupancy Prescribed fire Wildfire

Eye Disease and Eye Care Needs of West virginia:Results of the WV Eye Health Survey

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Eye Disease and Eye Care Needs of West Virginia:Results of t...

ANALYSES OF RECENT GEOMORPHIC EVOLUTION OF GARGATHY INLET, EASTERN SHORE OF virginia, U. S. A.

中华医学会第十二届全国眼科学术大会

作者： J.Vernon Odom West virginia University USA

We report results of a several statewide telephone sur- veys conducted in West *** purposes of these sur- veys was 1)to determine the need for low vision *** the state of WV,2)to determine how patients who visited

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Chinese Journal of Oceanology and Limnology 1992年第1期10卷 9-22页

作者：张乔民 R.J.Byrne G.R.Thomas South China Sea Institute of Oceanology Academia Sinica Guangzhou 510301 virginia Institute of Marine Science VA 23062 U.S.A

Uargathy Inlet is a small natural tidal inlet in the northern region ol the virginia Darner island chain. It is 100 m wide with a throat cross-sectional area of 384m2 and an average tidal prism of 6.47 x 106 m3. The inside drainage system is 7.8 km long and 2.2km wide. The main channels comprise 5.8% of the area, shallow lagoons 19.8%, and Spartina marshes 74.4% in 1970. Over the period 1851 - 1989 the inlet narrowed and migrated northward while maintaining a weakening downdrift offset. The nearby barrier island coastline’s rapid retreat (average rate 4.78m /a, 138 years retreat 660 m) was accompanied by back barrier channel and lagoon filling and a decrease in intertidal water volume which was probably the main reason for the entrance narrowing. The northward migration of the inlet was related to the dredging of the Inside Passage (before 1949) and the breaching of southern Metompkin Island (since 1957) connected with the inlet system. This altered the interior tidal circulation and likely shifted

关键词： geomorphic evolution Gargathy Inlet

Mercury concentrations in blood and feathers of nestling Bald Eagles in coastal and inland virginia

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Avian Research 2019年第1期10卷 36-42页

作者： David E.Kramar Bill Carstensen Steve Prisley Jim Campbell Department of Anthropology and Earth Science Minnesota State University Moorhead Department of Geography Virginia Tech National Council for Air and Stream Improvement

Background:Mercury(Hg) and methylmercury are widely considered significant issues for wildlife,and in particular,piscivorous birds due to their widespread availability and neurotoxic *** a substantial number of studies of Hg contamination of Bald Eagles(Haliaeetus leucocephalus) have been conducted throughout the east coast of the United States,little has been done that directly addresses Hg contamination in Bald Eagles in virginia,particularly the inland ***:We collected blood and feather samples from nestling Bald Eagles in the coastal plain,piedmont,and western regions of virginia in an effort to determine which areas of the state were more likely to contain populations showing evidence of Hg *** analyzed the samples for total Hg using a Milestone ***:Samples collected from individuals located in the coastal region exhibited low concentrations of Hg compared to those further inland located on freshwater rivers and *** collected from the inland population exhibited levels in some areas that are approaching what may be considered to be sub-lethal to avian health(blood:mean 0.324 mg/kg,SE = 0.13,range = 0.06-0.97 mg/kg;feather:mean = 8.433 mg/kg,SE = 0.3,range = 3.811-21.14 mg/kg).Conclusions:Even after accounting for known point-sources of Hg,the inland eagle population in virginia is susceptible to concentrations of Hg that are significantly higher than their coastal ***,several locations besides those currently known to be impacted by point-sources are exhibiting concentrations that are approaching a sub-lethal level.

关键词： Bald Eagle Haliaeetus leucocephalus Mercury Methyl-mercury virginia

Forests of West virginia,U.S.A. and Shaanxi,China:a study in forest exploitation and recovery

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Journal of Forestry Research 2004年第1期15卷 49-54,J002-J003页

作者： Jack E.Coster 彭鸿张秦岭 Morgantown West Virginia.U.S.A 陕西水土保持局西安710004 西北农林科技大学生命科学学院陕西杨凌712100

A review of the period of unregulated exploitation of forests in the state of West virginia (U.S.) and in Shaanxi Province, PRC was presented. Economic and ecological recovery from exploitation has been different in the two regions due to basic differences in nature of the forest and in the degree and persistence of exploitive pressures. After a century since unregulated exploitation, West virginia forests are well on the road to management for sustainability and conservation. Shaanxi's recovery from overuse and unregulated exploitation is less certain; forests are still in the early phases of ecological recovery there. Full recovery to a period of sustainability will take a century or longer. Suggestions are made for measures needed to enhance the forest recovery. Keywords Forests - Shaanxi - West virginia - Central China - Forest exploitation - Recovery CLC number S754 Document code A Article ID 1007-662X(2004)01-0049-06 Foundation item: The project was sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (2002–2004) and Shaanxi Provincial Foreign Expert Bureau (2003).Biography: Jack E. Coster (1935-), male, professor of West virginia University, Morgantown, West virginia. U.S.A.Responsible editor: Song Funan

关键词： Forests Shaanxi West virginia Central China Forest exploitation Recovery

An Analysis of Farming in the Rural Economic Development of West virginia

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Journal of Agricultural Science and Technology(B) 2012年第7期2卷 848-855页

作者： Saima Bashir Janaranjana Herath Tesfa Gebremedhin College of Business Administration and Public Affairs Lander University Greenwood SC 29649 USA Division of Resource Management West Virginia University Morgantown WV26506 USA

Farming is still an important sector in rural economic development of West virginia where 44% of the population lives in rural areas and 24% of the land is used for farming. While income earnings, education and employment rates are low in rural areas, poverty rates and unemployment are high compared to the urban areas. Thus, in the context of rural development farming is a potential major economic sector where 42% of the people＇s primary occupation is reported as farming. The objective of this study is to identify and estimate the potential impacts of farm employment in rural economic growth of West virginia. Data from U.S. Bureau of Labor Statistics and U.S Census Bureau for the period of 1993 to 2008 are used for the empirical analysis. A model derived from the three simultaneous equations of Duncan is used for analysis. Three-Stage Least Squares （3SLS） method using the statistical package of STATA is used for estimation. The results concerning simultaneous relationships with population density growth, per capita income growth, and farm employment growth reveal significant importance of farming in rural economic development of West virginia. Furthermore, the results indicate the positive impacts of population density, number of people with farming as principal occupation, and crop production on rural farming sector.

关键词： Farming rural economic development simultaneous equation 3SLS analysis West virginia.

Mechanisms for Cross-Scaling, Flexibility and Social Learning in Building Resilience to Sea Level Rise: Case Study of Hampton Roads, virginia

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American Journal of Climate Change 2017年第2期6卷 385-402页

作者： Carol Considine Michelle Covi Juita-Elena (Wie) Yusuf Batten College of Engineering & Technology Old Dominion University Norfolk VA USA College of Sciences Old Dominion University and Virginia Sea Grant Climate Adaptation and Resilience Program Norfolk VA USA Strome College of Business Old Dominion University Norfolk VA USA

This case study examines how the Hampton Roads Sea Level Rise Preparedness and Resilience Intergovernmental Planning Pilot Project, a whole-of-government and whole-of-community approach to planning for and adapting to sea level rise, addressed coastal resilience in a southeastern virginia watershed that spans multiple jurisdictions. Meeting the challenge of sea level rise requires that actors across multiple sectors—citizens, community organizations, industry and government—understand the risks and work together to make critical decisions regarding adaptation strategies and actions. The case study area includes Little Creek Amphibious Base, which is bordered by the cities of Norfolk and virginia Beach. Adaptation responses to sea level rise by the military base and the local governments will impact each other and the residents of the area, but no cooperative agreements are in place for a joint or collaborative response. This case study examines public and private infrastructure at risk, the infrastructure interdependencies, and mechanisms for providing collaborative solutions. Engagement of area residents and other stakeholders is also integral to the process of adaptation, which includes educating about sea level rise risk and provides a mechanism for social learning that enables stakeholders to participate in critical adaptation decisions. The case study demonstrates a method to improve resiliency in the case study area and inform a regional, multi-sectoral response to sea level rise adaptation strategies.

关键词： Sea Level Rise Multi-Sectoral Adaptation Hampton Roads Critical Infrastructure Social Learning Socio-Ecological Resilience Cross-Scaling

Grain Consumption and Production in virginia: A Trend and Spatial Examination

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Agricultural Sciences 2016年第4期7卷 250-269页

作者： Peter Caffarelli Gustavo Ferreira Gordon Groover Kathryn Boys Agricultural Marketing Service United States Department of Agriculture Washington DC USA Economic Research Service United States Department of Agriculture Washington DC USA Department of Agricultural and Applied Economics Virginia Tech Blacksburg VA USA Department of Agricultural and Resource Economics North Carolina State University Raleigh NC USA

This article couples an examination of grain production with virginia’s livestock and poultry sector to analyze the overall magnitude and distribution of grain consumption in virginia. Specifically, this paper describes the sources and trends over time of grain production and consumption;identifies grain surplus (and deficit) areas across virginia’s counties;describes and applies a methodology to quantify livestock and poultry consumption requirements at the state- and county-levels;provides an updated assessment of virginia’s ability to meet its feed grain needs;and discusses implications on the overall distribution system. Important results of the analysis reveal that grain consumption in virginia is due mainly to demand in the poultry sector (primarily broilers and chickens). Furthermore, grain consumption in this state has generally declined over the last twenty years, due to decreasing livestock population numbers. Coupled with a slight upward trend in grain production, virginia appears to be increasingly capable of meeting its grain needs. There is, however, an important east-west divide in the state, with western counties requiring more grain than they produce. Since grain does not appear to move from the relatively “production-rich” eastern counties, transportation infrastructure is important to bring in grain from outside the state.

关键词： Animal Feed-Grain County Grain Consuming Animal Unit