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Burned Area Mapping Of An Escaped Fire Into Tropical Dry Forest In Western Madagascar Using Multi-Season Landsat Oli Data, Anne C. Axel Mar 2018

Burned Area Mapping Of An Escaped Fire Into Tropical Dry Forest In Western Madagascar Using Multi-Season Landsat Oli Data, Anne C. Axel

Biological Sciences Faculty Research

A human-induced fire cleared a large area of tropical dry forest near the Ankoatsifaka Research Station at Kirindy Mitea National Park in western Madagascar over several weeks in 2013. Fire is a major factor in the disturbance and loss of global tropical dry forests, yet remotely sensed mapping studies of fire-impacted tropical dry forests lag behind fire research of other forest types. Methods used to map burns in temperature forests may not perform as well in tropical dry forests where it can be difficult to distinguish between multiple-age burn scars and between bare soil and burns. In this study, the …


Forest Ecosystems Of Temperate Climatic Regions: From Ancient Use To Climate Change, Frank S. Gilliam Dec 2016

Forest Ecosystems Of Temperate Climatic Regions: From Ancient Use To Climate Change, Frank S. Gilliam

Biological Sciences Faculty Research

Humans have long utilized resources from all forest biomes, but the most indelible anthropogenic signature has been the expanse of human populations in temperate forests. The purpose of this review is to bring into focus the diverse forests of the temperate region of the biosphere, including those of hardwood, conifer and mixed dominance, with a particular emphasis on crucial challenges for the future of these forested areas. Implicit in the term ‘temperate’ is that the predominant climate of these forest regions has distinct cyclic, seasonal changes involving periods of growth and dormancy. The specific temporal patterns of seasonal change, however, …


Effects Of Excess Nitrogen On Biogeochemistry Of A Temperate Hardwood Forest: Evidence Of Nutrient Redistribution By A Forest Understory Species, Frank S. Gilliam, Jake H. Billmyer, Christopher A. Walter, William T. Peterjohn Dec 2016

Effects Of Excess Nitrogen On Biogeochemistry Of A Temperate Hardwood Forest: Evidence Of Nutrient Redistribution By A Forest Understory Species, Frank S. Gilliam, Jake H. Billmyer, Christopher A. Walter, William T. Peterjohn

Biological Sciences Faculty Research

Excess nitrogen (N) in terrestrial ecosystems can arise from anthropogenically-increased atmospheric N deposition, a phenomenon common in eastern US forests. In spite of decreased N emissions over recent years, atmospheric concentrations of reactive N remain high in areas within this region. Excess N in forests has been shown to alter biogeochemical cycling of essential plant nutrients primarily via enhanced production and leaching of nitrate, which leads to loss of base cations from the soil. The purpose of our study was to investigate this phenomenon using a multifaceted approach to examine foliar nutrients of two herbaceous layer species in one N-treated …


Twenty-Five Year Response Of The Herbaceous Layer Of A Temperate Hardwood Forest To Elevated Nitrogen Deposition, Frank S. Gilliam, Nicole Turrill Welch, Anne Hockenberry Phillips, Jake H. Billmyer, William T. Peterjohn, Zachariah K. Fowler, Christopher A. Walter, Mark B. Burnham, Jeffrey D. May, Mary Beth Adams Jan 2016

Twenty-Five Year Response Of The Herbaceous Layer Of A Temperate Hardwood Forest To Elevated Nitrogen Deposition, Frank S. Gilliam, Nicole Turrill Welch, Anne Hockenberry Phillips, Jake H. Billmyer, William T. Peterjohn, Zachariah K. Fowler, Christopher A. Walter, Mark B. Burnham, Jeffrey D. May, Mary Beth Adams

Biological Sciences Faculty Research

Increasing rates of atmospheric deposition of nitrogen (N) present a novel threat to the biodiversity of terrestrial ecosystems. Many forests are particularly susceptible to excess N given their proximity to sources of anthropogenic N emissions. This study summarizes results of a 25-yr treatment of an entire central Appalachian hardwood forest watershed via aerial applications of N with a focus on effects of added N on the cover, species richness, and composition of the herbaceous layer. Research was carried out on two watersheds of the Fernow Experimental Forest (FEF), West Virginia. The long-term reference watershed at FEF (WS4) was used as …


In Situ Nitrogen Mineralization, Nitrification, And Ammonia Volatilization In Maize Field Fertilized With Urea In Huanghuaihai Region Of Northern China, Xuelin Zhang, Qun Wang, Jun Xu, Frank S. Gilliam, Nicolas Tremblay, Chaohai Li Jan 2015

In Situ Nitrogen Mineralization, Nitrification, And Ammonia Volatilization In Maize Field Fertilized With Urea In Huanghuaihai Region Of Northern China, Xuelin Zhang, Qun Wang, Jun Xu, Frank S. Gilliam, Nicolas Tremblay, Chaohai Li

Biological Sciences Faculty Research

Nitrogen (N) fertilization potentially affects soil N mineralization and leaching, and can enhance NH3 volatilization, thus impacting crop production. A fertilizer experiment with five levels of N addition (0, 79, 147, 215 and 375 kg N ha-1) was performed in 2009 and 2010 in a maize field in Huanghuaihai region, China, where > 300 kg N ha-1 has been routinely applied to soil during maize growth period of 120 days. Responses of net N mineralization, inorganic N flux (0–10cm), NH3 volatilization, and maize yield to N fertilization were measured. During the growth period, net N mineralization …


A Novel Mechanism To Explain Success Of Invasive Herbaceous Species At The Expense Of Natives In Eastern Hardwood Forests, Frank S. Gilliam Jan 2015

A Novel Mechanism To Explain Success Of Invasive Herbaceous Species At The Expense Of Natives In Eastern Hardwood Forests, Frank S. Gilliam

Biological Sciences Faculty Research

Among the more intriguing topics in general ecology courses are the symbiotic relationships (the ‘-isms’ as I sometimes present them – mutualism, commensalism, and parasitism). Of these, mutualism is typically the most appealing to students. The scenario that different species can not only co-exist, but can also provide essential resources/services for one another, resonates well with all but the least interested in the course. Ultimately, however, there is also the palpable degree of dismay when they discover that these relationships arise from mutual exploitation, rather than from some benign force of nature. A flip-side of this, in many ways a …


Spatial Variation In Carbon And Nitrogen In Cultivated Soils In Henan Province, China: Potential Effect On Crop Yield, Xuelin Zhang, Qun Wang, Frank S. Gilliam, Yilun Wang, Feina Cha, Chaohai Li Oct 2014

Spatial Variation In Carbon And Nitrogen In Cultivated Soils In Henan Province, China: Potential Effect On Crop Yield, Xuelin Zhang, Qun Wang, Frank S. Gilliam, Yilun Wang, Feina Cha, Chaohai Li

Biological Sciences Faculty Research

Improved management of soil carbon (C) and nitrogen (N) storage in agro-ecosystems represents an important strategy for ensuring food security and sustainable agricultural development in China. Accurate estimates of the distribution of soil C and N stores and their relationship to crop yield are crucial to developing appropriate cropland management policies. The current study examined the spatial variation of soil organic C (SOC), total soil N (TSN), and associated variables in the surface layer (0–40 cm) of soils from intensive agricultural systems in 19 counties within Henan Province, China, and compared these patterns with crop yield. Mean soil C and …


Nitrogen Deposition Contributes To Soil Acidification In Tropical Ecosystems, Xiankai Lu, Qinggong Mao, Frank S. Gilliam, Yiqi Luo, Jiangming Mo Jun 2014

Nitrogen Deposition Contributes To Soil Acidification In Tropical Ecosystems, Xiankai Lu, Qinggong Mao, Frank S. Gilliam, Yiqi Luo, Jiangming Mo

Biological Sciences Faculty Research

Elevated anthropogenic nitrogen (N) deposition has greatly altered terrestrial ecosystem functioning, threatening ecosystem health via acidification and eutrophication in temperate and boreal forests across the northern hemisphere. However, response of forest soil acidification to N deposition has been less studied in humid tropics compared to other forest types. This study was designed to explore impacts of long-term N deposition on soil acidification processes in tropical forests. We have established a long-term N deposition experiment in an N-rich lowland tropical forest of Southern China since 2002 with N addition as NH4NO3 of 0, 50, 100 and 150 kg …


Variation In Vegetation And Microbial Linkages With Slope Aspect In A Montane Temperate Hardwood Forest, Frank S. Gilliam, Radim Hedl, Marketa Chudomelova, Rebecca L. Mcculley, Jim Nelson May 2014

Variation In Vegetation And Microbial Linkages With Slope Aspect In A Montane Temperate Hardwood Forest, Frank S. Gilliam, Radim Hedl, Marketa Chudomelova, Rebecca L. Mcculley, Jim Nelson

Biological Sciences Faculty Research

Plant ecologists have long been interested in aspect-related contrasts of montane forests. Few studies have assessed correlation (linkage) among vegetation strata; fewer have included soil microbial communities. This study assessed contrasts in overstory, spring herbaceous, and soil microbial communities between northeast (NE) - and southwest (SW) -facing slopes in a second-growth West Virginia hardwood forest. We addressed three questions: (1) how do soil microbial, herbaceous layer, and overstory communities vary with slope aspect? (2) do forest vegetation strata and soil microbial communities exhibit linkage? (3) do biotic relationships and linkage vary with slope aspect? Moisture, organic matter, pH, soil NO …


Nutrient Limitation In Three Lowland Tropical Forests In Southern China Receiving High Nitrogen Deposition: Insights From Fine Root Responses To Nutrient Additions, Feifei Zhu, Muneoki Yoh, Frank S. Gilliam, Xiankai Lu, Jiangming Mo Dec 2013

Nutrient Limitation In Three Lowland Tropical Forests In Southern China Receiving High Nitrogen Deposition: Insights From Fine Root Responses To Nutrient Additions, Feifei Zhu, Muneoki Yoh, Frank S. Gilliam, Xiankai Lu, Jiangming Mo

Biological Sciences Faculty Research

Elevated nitrogen (N) deposition to tropical forests may accelerate ecosystem phosphorus (P) limitation. This study examined responses of fine root biomass, nutrient concentrations, and acid phosphatase activity (APA) of bulk soil to five years of N and P additions in one old-growth and two younger lowland tropical forests in southern China. The old-growth forest had higher N capital than the two younger forests from long-term N accumulation. From February 2007 to July 2012, four experimental treatments were established at the following levels: Control, N-addition (150 kg N ha–1 yr–1), P-addition (150 kg P ha–1 yr–1 …


Changes In Soil Carbon Sequestration In Pinus Massoniana Forests Along An Urban-To-Rural Gradient Of Southern China, H. Chen, W. Zhang, Frank S. Gilliam, L. Liu, J. Huang, T. Zhang, W. Wang, J. Mo Oct 2013

Changes In Soil Carbon Sequestration In Pinus Massoniana Forests Along An Urban-To-Rural Gradient Of Southern China, H. Chen, W. Zhang, Frank S. Gilliam, L. Liu, J. Huang, T. Zhang, W. Wang, J. Mo

Biological Sciences Faculty Research

Urbanization is accelerating globally, causing a variety of environmental changes such as increases in air temperature, precipitation, atmospheric CO2, and nitrogen (N) deposition. However, the effects of these changes on forest soil carbon (C) sequestration remain largely unclear. Here, we used urban-to-rural environmental gradients in Guangdong Province, southern China, to address the potential effects of these environmental changes on soil C sequestration in Pinus massoniana forests. In contrast to our expectations and earlier observations, soil C content in urban sites was significantly lower than that in suburban and rural sites. Lower soil C pools in urban sites were …


Long-Term Nitrogen Addition Decreases Carbon Leaching In A Nitrogen-Rich Forest Ecosystem, X. Lu, Frank S. Gilliam, G. Yu, H. Chen, J. Mo Jun 2013

Long-Term Nitrogen Addition Decreases Carbon Leaching In A Nitrogen-Rich Forest Ecosystem, X. Lu, Frank S. Gilliam, G. Yu, H. Chen, J. Mo

Biological Sciences Faculty Research

Dissolved organic carbon (DOC) plays a critical role in the carbon (C) cycle of forest soils, and has been recently connected with global increases in nitrogen (N) deposition. Most studies on effects of elevated N deposition on DOC have been carried out in N-limited temperate regions, with far fewer data available from N-rich ecosystems, especially in the context of chronically elevated N deposition. Furthermore, mechanisms for excess N-induced changes of DOC dynamics have been suggested to be different between the two kinds of ecosystems, because of the different ecosystem N status. The purpose of this study was to experimentally examine …


Interactive Effects Of Nitrogen And Phosphorus On Soil Microbial Communities In A Tropical Forest, Lei Liu, Tao Zhang, Frank S. Gilliam, Per Gundersen, Wei Zhang, Hao Chen, Jiangming Mo Apr 2013

Interactive Effects Of Nitrogen And Phosphorus On Soil Microbial Communities In A Tropical Forest, Lei Liu, Tao Zhang, Frank S. Gilliam, Per Gundersen, Wei Zhang, Hao Chen, Jiangming Mo

Biological Sciences Faculty Research

Elevated nitrogen (N) deposition in humid tropical regions may exacerbate phosphorus (P) deficiency in forests on highly weathered soils. However, it is not clear how P availability affects soil microbes and soil carbon (C), or how P processes interact with N deposition in tropical forests. We examined the effects of N and P additions on soil microbes and soil C pools in a N-saturated old-growth tropical forest in southern China to test the hypotheses that (1) N and P addition will have opposing effects on soil microbial biomass and activity, (2) N and P addition will alter the composition of …


Estimated Losses Of Plant Biodiversity Across The U.S. From Historical N Deposition From 1985—2010., Christopher M. Clark, Philip E. Morefield, Frank S. Gilliam, Linda H. Pardo Feb 2013

Estimated Losses Of Plant Biodiversity Across The U.S. From Historical N Deposition From 1985—2010., Christopher M. Clark, Philip E. Morefield, Frank S. Gilliam, Linda H. Pardo

Biological Sciences Faculty Research

Although nitrogen (N) deposition is a significant threat to herbaceous plant biodiversity worldwide, it is not a new stressor for many developed regions. Only recently has it become possible to estimate historical impacts nationally for the United States. We used 26 years (1985–2010) of deposition data, with ecosystem-specific functional responses from local field experiments and a national critical loads (CL) database, to generate scenario-based estimates of herbaceous species loss. Here we show that, in scenarios using the low end of the CL range, N deposition exceeded critical loads over 0.38, 6.5, 13.1, 88.6, and 222.1 million ha for the Mediterranean …


Effect Of Nitrogen Fertilization On Net Nitrogen Mineralization In Grassland Soil Of Northern China: Implications For Grassland Management, X. Zhang, Q. Wang, Frank S. Gilliam, W. Bai, X. Han, L. Li Jan 2012

Effect Of Nitrogen Fertilization On Net Nitrogen Mineralization In Grassland Soil Of Northern China: Implications For Grassland Management, X. Zhang, Q. Wang, Frank S. Gilliam, W. Bai, X. Han, L. Li

Biological Sciences Faculty Research

Nitrogen (N) applications can have a significant effect on soil N availability. The effect of 3 years of N fertilization on soil net N mineralization during the growing season (May–September) was studied in 2005 and 2006 in grassland of northern China. The experimental design was a randomized complete block with four replications of five rates of N addition as urea (0, 2, 4, 8 and 16 g N m−2 year−1). Results indicated that net N mineralization rate varied seasonally and between years, ranging from −0.04 to 0.52 μg g−1 d−1 in 2005 and from −0.09 …


Effects Of Experimental Nitrogen Additions On Plant Diversity In Tropical Forests Of Contrasting Disturbance Regimes In Southern China, Xiankai Lu, Jiangming Mo, Frank S. Gilliam, Guirui Yu, Wei Zhang, Yunting Fang, Juan Huang Oct 2011

Effects Of Experimental Nitrogen Additions On Plant Diversity In Tropical Forests Of Contrasting Disturbance Regimes In Southern China, Xiankai Lu, Jiangming Mo, Frank S. Gilliam, Guirui Yu, Wei Zhang, Yunting Fang, Juan Huang

Biological Sciences Faculty Research

Responses of understory plant diversity to nitrogen (N) additions were investigated in reforested forests of contrasting disturbance regimes in southern China from 2003 to 2008: disturbed forest (withharvesting of understory vegetation and litter) and rehabilitated forest (without harvesting). Experimental additions of N were administered as the following treatments: Control, 50 kg N ha1yr1, and 100kg N ha1yr1. Nitrogen additions did not significantly affect understory plant richness, density,and cover in the disturbed forest. Similarly, no significant response was found for canopy closure in thisforest. In the rehabilitated forest, species richness and density showed no significant response to Nadditions; however, understory cover …


Eastern Temperate Forests, Frank S. Gilliam, Christine L. Goodale, Linda H. Pardo, Linda H. Geiser, Erik A. Lilleskov May 2011

Eastern Temperate Forests, Frank S. Gilliam, Christine L. Goodale, Linda H. Pardo, Linda H. Geiser, Erik A. Lilleskov

Biological Sciences Faculty Research

Human activity in the last century has led to a substantial increase in nitrogen (N) emissions and deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the level of pollution that would be harmful to ecosystems is the critical loads approach. The critical load is dei ned as the level of a pollutant below which no detrimental ecological effect occurs over the long term according to present knowledge.

The objective of this project was to synthesize …


0784: L. D. Fowler Papers, 1900-1920, Marshall University Special Collections Jan 2011

0784: L. D. Fowler Papers, 1900-1920, Marshall University Special Collections

Guides to Manuscript Collections

The papers in this collection are both the professional and personal records of L.D. Fowler from 1900-1920 while working out of Durbin, WV. As an employee of the Pocahontas Tanning Company, L.D. Fowler’s business papers relate primarily to timber and the acquisition of bark associated with the tanning process. Among the type of materials included in the collection are correspondences (i.e. letters, telegraphs, and postcards), well-documented business transactions with a wide range of business partners, business cards, diaries, maps, popular culture items (calendars, etc.), and materials related to legal issues and political affiliations. This collection is divided into two overarching …


Effects Of Nitrogen On Temporal And Spatial Patterns Of Nitrate In Streams And Soil Solution Of A Central Hardwood Forest, Frank S. Gilliam, Mary Beth Adams Jan 2011

Effects Of Nitrogen On Temporal And Spatial Patterns Of Nitrate In Streams And Soil Solution Of A Central Hardwood Forest, Frank S. Gilliam, Mary Beth Adams

Biological Sciences Faculty Research

This study examined changes in stream and soil water NO3−and their relationship to temporal and spatial patterns of NO3−in soil solution of watersheds at the Fernow Experimental Forest, West Virginia. Following tenfold increases in stream NO3−concentrations over a 13-year period (1969–1981) on untreated WS4, concentrations have declined through 2006. Followingfourfold increases in stream NO3−on treatment WS3 from pretreatment levels to a 1998 maximum, concentrations have declinedthrough 2006, despite additions of N. Concentrations of soil water NO3−were consistently lower for WS4 compared to WS3.Data for soil water NO3−on WS3 versus WS4 followed patterns of net mineralization and nitrification for these watersheds.Nitrogen …


Nitrogen Addition Shapes Soil Phosphorus Availability In Two Reforested Tropical Forests In Southern China, Xiankai Lu, Jiangming Mo, Frank S. Gilliam, Hua Fang, Feifei Zhu, Yunting Fang, Wei Zhang, Juan Huang Jan 2011

Nitrogen Addition Shapes Soil Phosphorus Availability In Two Reforested Tropical Forests In Southern China, Xiankai Lu, Jiangming Mo, Frank S. Gilliam, Hua Fang, Feifei Zhu, Yunting Fang, Wei Zhang, Juan Huang

Biological Sciences Faculty Research

Scant information is available on how soil phosphorus (P) availability responds to atmospheric nitrogen (N) deposition, especially in the tropical zones. This study examined the effect of N addition on soil P availability, and compared this effect between forest sites of contrasting land-use history. Effects of N addition on soil properties, litterfall production, P release from decomposing litter, and soil P availability were studied in a disturbed (reforested pine forest with previous understory vegetation and litter harvesting) and a rehabilitated (reforested mixed pine/broadleaf forest with no understory vegetation and litter harvesting) tropical forest in southern China. Experimental N-treatments (above ambient) …


Effects Of Experimental Nitrogen Additions On Plant Diversity In An Old-Growth Tropical Forest, Xiankai Lu, Jiangming Mo, Frank S. Gilliam, Guoyi Zhou, Yunting Fang Oct 2010

Effects Of Experimental Nitrogen Additions On Plant Diversity In An Old-Growth Tropical Forest, Xiankai Lu, Jiangming Mo, Frank S. Gilliam, Guoyi Zhou, Yunting Fang

Biological Sciences Faculty Research

Response of plant biodiversity to increased availability of nitrogen (N) has been investigated in temperate and boreal forests, which are typically N-limited, but little is known in tropical forests. We examined the effects of artificial N additions on plant diversity (species richness, density and cover) of the understory layer in an N saturated old-growth tropical forest in southern China to test the following hypothesis: N additions decrease plant diversity in N saturated tropical forests primarily from N-mediated changes in soil properties. Experimental additions of N were administered at the following levels from July 2003 to July 2008: no addition (Control); …


Effects Of Experimental Freezing On Soil Nitrogen Dynamics In Soils From A Net Nitrification Gradient In A Nitrogen-Saturated Hardwood Forest Ecosystem, Frank S. Gilliam, Adam Cook, Salina Lyter Mar 2010

Effects Of Experimental Freezing On Soil Nitrogen Dynamics In Soils From A Net Nitrification Gradient In A Nitrogen-Saturated Hardwood Forest Ecosystem, Frank S. Gilliam, Adam Cook, Salina Lyter

Biological Sciences Faculty Research

This study examined effects of soil freezing on N dynamics in soil along an N processing gradient within a mixed hardwood dominated watershed at Fernow Experimental Forest, West Virginia. Sites were designated as LN (low rates of N processing), ML (moderately low), MH (moderately high), and HN (high). Soils underwent three 7-day freezing treatments (0, –20, or –80 °C) in the laboratory. Responses varied between temperature treatments and along the gradient. Initial effects differed among freezing treatments for net N mineralization, but not nitrification, in soils across the gradient, generally maintained at LN < ML ≤ MH < HN for all treatments. Net N mineralization potential was higher following freezing at –20 and –80 °C than control; all were higher than at 0 °C. Net nitrification potential exhibited similar patterns. LN was an exception, with net nitrification low regardless of treatment. Freezing response of N mineralization differed greatly from that of nitrification, suggesting that soil freezing may decouple two processes of the soil N cycle that are otherwise tightly linked at our site. Results also suggest that soil freezing at temperatures commonly experienced at this site can further increase net nitrification in soils already exhibiting high nitrification from N saturation.


Global Assessment Of Nitrogen Deposition Effects On Terrestrial Plant Diversity : A Synthesis, R. Bobbink, K. Hicks, J. Galloway, T. Spranger, R. Alkemade, M. Ashmore, M. Bustamante, S. Cinderby, E. Davidson, F. Dentener, B. Emmett, J. W. Erisman, M. Fenn, Frank S. Gilliam, A. Nordin, L. Pardo, W. Devries Jan 2010

Global Assessment Of Nitrogen Deposition Effects On Terrestrial Plant Diversity : A Synthesis, R. Bobbink, K. Hicks, J. Galloway, T. Spranger, R. Alkemade, M. Ashmore, M. Bustamante, S. Cinderby, E. Davidson, F. Dentener, B. Emmett, J. W. Erisman, M. Fenn, Frank S. Gilliam, A. Nordin, L. Pardo, W. Devries

Biological Sciences Faculty Research

Atmospheric nitrogen (N) deposition is a recognized threat to plant diversity in temperate and northern parts of Europe and North America. This paper assesses evidence from field experiments for N deposition effects and thresholds for terrestrial plant diversity protection across a latitudinal range of main categories of ecosystems, from arctic and boreal systems to tropical forests. Current thinking on the mechanisms of N deposition effects on plant diversity, the global distribution of G200 ecoregions, and current and future (2030) estimates of atmospheric N-deposition rates are then used to identify the risks to plant diversity in all major ecosystem types now …


The Ecological Significance Of The Herbaceous Layer In Temperate Forest Ecosystems, Frank S. Gilliam Nov 2007

The Ecological Significance Of The Herbaceous Layer In Temperate Forest Ecosystems, Frank S. Gilliam

Biological Sciences Faculty Research

Despite a growing awareness that the herbaceous layer serves a special role in maintaining the structure and function of forests, this stratum remainsan underappreciated aspect of forest ecosystems. In this article I review and synthesize information concerning the herb layer’s structure,composition, and dynamics to emphasize its role as an integral component of forest ecosystems. Because species diversity is highest in the herb layeramong all forest strata, forest biodiversity is largely a function of the herb-layer community. Competitive interactions within the herb layer candetermine the initial success of plants occupying higher strata, including the regeneration of dominant overstory tree species. Furthermore, …


Response Of The Herbaceous Layer Of Forest Ecosystems To Excess Nitrogen Deposition, Frank S. Gilliam Nov 2006

Response Of The Herbaceous Layer Of Forest Ecosystems To Excess Nitrogen Deposition, Frank S. Gilliam

Biological Sciences Faculty Research

  • 1 This review brings into focus what is known about the response of the herbaceous layer of forest ecosystems to increasing nitrogen deposition. The emphasis on forests in general is important for two reasons. First, forests often occupy areas receiving high rates of atmospheric deposition of N. Second, compared with herb-dominated communities, about which much is known regarding response to excess N, forests generally display greater biological and structural complexity. The more specific focus on the herbaceous layer – here defined as all vascular (herbaceous and woody) plants ≤ 1 m in height – is warranted because most of the …


Conservation And Restoration Of The Pinus Palustris Ecosystem, Frank S. Gilliam, William J. Platt May 2006

Conservation And Restoration Of The Pinus Palustris Ecosystem, Frank S. Gilliam, William J. Platt

Biological Sciences Faculty Research

The well-documented decline of the Pinus palustris ecosystem has resulted from several anthropogenic influences, such as forest clearing (e.g. pine plantation forestry, agriculture) and urban development, both of which are closely related to increases in human populations. Other impacts have arisen from alterations in disturbance regimes responsible for maintaining the structure and function of these ecosystems. Restoration and management of degraded pine savanna ecosystems is critical. Identification of ecological processes that determine the structure and function of the intact system are important because successful restoration efforts should be based on sound scientific understanding. In this paper, we introduce this special …


Natural Disturbances And The Physiognomy Of Pine Savannas : A Phenomenological Model, Frank S. Gilliam, William J. Platt, Robert K. Peet May 2006

Natural Disturbances And The Physiognomy Of Pine Savannas : A Phenomenological Model, Frank S. Gilliam, William J. Platt, Robert K. Peet

Biological Sciences Faculty Research

Abstract. Question: The decline of the Pinus palustris ecosystems has resulted from anthropogenic influences, such as conversion to pine plantation forestry, agriculture and land development, all of which are closely related to increases in human populations. Other effects, however, have arisen from alterations in disturbance regimes that maintain the structure and function of these ecosystems. How have alterations of the disturbance regime altered the physiognomy of ‘old-growth’ stands, and what are the implications for ecosystem conservation and restoration?

Methods: In contrast to models that emphasize close interactions among the vertically complex strata, we develop a conceptual phenomenological model for the …


Effects Of Atmospheric Nitrogen Deposition On The Herbaceous Layer Of A Central Appalachian Hardwood Forest, Frank S. Gilliam, Anne W. Hockenberry, Mary Beth Adams Apr 2006

Effects Of Atmospheric Nitrogen Deposition On The Herbaceous Layer Of A Central Appalachian Hardwood Forest, Frank S. Gilliam, Anne W. Hockenberry, Mary Beth Adams

Biological Sciences Faculty Research

Additions of nitrogen (N) have been shown to alter species diversity of plant communities, with most experimental studies having been carried out in communities dominated by herbaceous species. We examined seasonal and inter-annual patterns of change in the herbaceous layer of two watersheds of a central Appalachian hardwood forest that differed in experimental treatment. This study was carried out at the Fernow Experimental Forest, West Virginia, using two adjacent watersheds: WS4 (mature, second-growth hardwood stand, untreated reference), and WS3. Seven circular 0.04-ha sample plots were established in eachwatershed to represent its full range of elevation and slope aspect. The herbaceous …


Acidification And Nutrient Cycling, Mary Beth Adams, William T. Peterjohn, Frank S. Gilliam Jan 2006

Acidification And Nutrient Cycling, Mary Beth Adams, William T. Peterjohn, Frank S. Gilliam

Biological Sciences Faculty Research

Additions of acid anions can alter the cycling of other nutrients and elements within an ecosystem. As strong acid ions move through a forest, they may increase the concentrations of nitrogen (N) and sulfur (S) in the soil solution and stream water. Such treatments also may increase or decrease the availability of other anions, cations and metal ions in the soil. A number of studies in Europe and North America have documented increases in base cation concentrations such as calcium (Ca) and magnesium (Mg) with increased N and S deposition (Foster and Nicolson 1988, Feger 1992, Norton et al. 1994, …


Vegetation And Acidification, David R. Dewalle, James N. Kochenderfer, Mary Beth Adams, Gary W. Miller, Frank S. Gilliam, Frederica Wood, Stephanie S. Odenwald-Clemens, William E. Sharpe Jan 2006

Vegetation And Acidification, David R. Dewalle, James N. Kochenderfer, Mary Beth Adams, Gary W. Miller, Frank S. Gilliam, Frederica Wood, Stephanie S. Odenwald-Clemens, William E. Sharpe

Biological Sciences Faculty Research

In this chapter, the impact of watershed acidification treatments on WS3 at the Fernow Experimental Forest (FEF) and at WS9 on vegetation is presented and summarized in a comprehensive way for the first time. WS7 is used as a vegetative reference basin for WS3, while untreated plots within WS9 are used as a vegetative reference for WS9. Bioindicators of acidification impacts that will be considered include several measures of tree and stand growth rates, foliar chemistry, bolewood chemistry, and herbaceous species composition and diversity. These studies enhance our understanding of the inter-relationships of changes in soil conditions caused by the …