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Comparison of the spatio-temporal dynamics of vegetation between the Changbai Mountains of eastern Eurasia and the Appalachian Mountains of eastern North America 被引量:3
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作者 GUO Xiao-yi ZHANG Hong-yan +5 位作者 WANG Ye-qiao HE Hong-shi WU Zheng-fang JIN Ying-hua ZHANG Zheng-xiang ZHAO Jian-jun 《Journal of Mountain Science》 SCIE CSCD 2018年第1期1-12,共12页
The Changbai Mountains and the Appalachian Mountains have similar spatial contexts.The elevation,latitude,and moisture gradients of both mountain ranges offer regional insight for investigating the vegetation dynamics... The Changbai Mountains and the Appalachian Mountains have similar spatial contexts.The elevation,latitude,and moisture gradients of both mountain ranges offer regional insight for investigating the vegetation dynamics in eastern Eurasia and eastern North America.We determined and compared the spatial patterns and temporal trends in the normalized difference vegetation index(NDVI)in the Changbai Mountains and the Appalachian Mountains using time series data from the Global Inventory Modeling and Mapping Studies 3^(rd) generation dataset from 1982 to 2013.The spatial pattern of NDVI in the Changbai Mountains exhibited fragmentation,whereas NDVI in the Appalachian Mountains decreased from south to north.The vegetation dynamics in the Changbai Mountains had an insignificant trend at the regional scale,whereas the dynamics in the Appalachian Mountains had a significant increasing trend.NDVI increased in 55% of the area of the Changbai Mountains and in 95% of the area of the Appalachian Mountains.The peak NDVI occurred one month later in the Changbai Mountains than in the Appalachian Mountains.The results revealed a significant increase in NDVI in autumn in both mountain ranges.The climatic trend in the Changbai Mountains included warming and decreased precipitation,and whereas that in the Appalachian Mountains included significant warming and increased precipitation.Positive and negative correlations existed between NDVI and temperature and precipitation,respectively,in both mountain ranges.Particularly,the spring temperature and NDVI exhibited a significant positive correlation in both mountain ranges.The results of this study suggest that human actives caused the differences in the spatial patterns of NDVI and that various characteristics of climate change and intensity of human actives dominated the differences in the NDVI trends between the Changbai Mountains and the Appalachian Mountains.Additionally,the vegetation dynamics of both mountain ranges were not identical to those in previous broader-scale studies. 展开更多
关键词 Changbai mountains appalachian mountains Vegetation dynamics Vegetation index Climate factors Human activities
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Predicting intensity of white-tailed deer herbivory in the Central Appalachian Mountains
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作者 Andrew B.Kniowski W.Mark Ford 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第3期830-839,共10页
In eastern North America, white-tailed deer(Odocoileus virginianus) can have profound influences on forest biodiversity and forest successional processes.Moderate to high deer populations in the central Appalachians h... In eastern North America, white-tailed deer(Odocoileus virginianus) can have profound influences on forest biodiversity and forest successional processes.Moderate to high deer populations in the central Appalachians have resulted in lower forest biodiversity.Legacy effects in some areas persist even following deer population reductions or declines. This has prompted managers to consider deer population management goals in light of policies designed to support conservation of biodiversity and forest regeneration while continuing to support ample recreational hunting opportunities. However,despite known relationships between herbivory intensity and biodiversity impact, little information exists on the predictability of herbivory intensity across the varied and spatially diverse habitat conditions of the central Appalachians. We examined the predictability of browsing rates across central Appalachian landscapes at four environmental scales: vegetative community characteristics, physical environment, habitat configuration, and local human and deer population demographics. In an information-theoretic approach, we found that a model fitting the number of stems browsed relative to local vegetation characteristics received most(62%) of the overall support of all tested models assessing herbivory impact. Our data suggest that deer herbivory responded most predictably to differences in vegetation quantity and type. No other spatial factors or demographic factors consistently affected browsing intensity. Because herbivory, vegetation communities, and productivity vary spatially, we suggest that effective broad-scale herbivory impact assessment should include spatially-balanced vegetation monitoring that accounts for regional differences in deer forage preference.Effective monitoring is necessary to avoid biodiversity impacts and deleterious changes in vegetation community composition that are difficult to reverse and/or may not be detected using traditional deer-density based management goals. 展开更多
关键词 BIODIVERSITY Central appalachian mountains HERBIVORY Odocoileus virginianus Predicting browsing intensity White-tailed deer
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Effects of historic wildfire and prescribed fire on site occupancy of bats in Shenandoah National Park,Virginia,USA
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作者 Lauren V.Austin Alexander Silvis +1 位作者 W.Mark Ford Karen E.Powers 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第4期1255-1270,共16页
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... 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 populations.Historic wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning,implementing and assessing burn programs.To 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,USA.There was limited evidence of positive fire effects over time on hoary bats(Lasiurus cinereus Beauvois)and big brown bats(Eptesicus fuscus Beauvois)occupancy.Overall,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 approach.Our results suggest that fire does not strongly affect bat site occupancy short-or long-term in the central Appalachians. 展开更多
关键词 appalachian mountains Bats False-positive occupancy Prescribed fire WILDFIRE
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Stipitate hydnoid fungi of the temperate southeastern United States
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作者 Richard Baird Lisa E.Wallace +1 位作者 Gerald Baker Mary Scruggs 《Fungal Diversity》 SCIE 2013年第5期41-114,共74页
An 11 year study was conducted to reevaluate the species of stipitate hydnums from the southern United States especially the Great Smoky Mountains and surrounding geography.The genera evaluated included Bankera herein... An 11 year study was conducted to reevaluate the species of stipitate hydnums from the southern United States especially the Great Smoky Mountains and surrounding geography.The genera evaluated included Bankera herein reduced to synonym with Phellodon,Hydnellum,Sarcodon,and Phellodon.Basidiomata of many stipitate hydnum species from this region were abundant but nitrogen depositions during the last 20 years have impacted their occurrences.Therefore it became critical to do a definitive study of these fungi using current taxonomic tools.Many species within Hydnellum and Phellodon have a indeterminate type growth often dependant on environmental conditions making discrimination between closely related species difficult without supportive molecular sequence data.Once sequence data(ITS)was obtained a phylogenetic analyzes were conducted and the sequences were compared to those in GenBank with particular attention to European data.A total of 41 distinct taxa were determined and many of those were confirmed based on morphological data.A specific new combination from Bankera fuligineoalbum to Phellodon fuligineoalbus is made herein.Futhermore,Phellodon brunneoolivaceus is described as new based on morphological and sequence data. 展开更多
关键词 Stipitate hydnums Southern appalachian mountains Morphological and molecular data Three genera
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