Time filter

Source Type

Fort Davis, WV, United States

Constantz G.D.,Canaan Valley Institute
Southeastern Naturalist | Year: 2015

To place the prehistoric people of Canaan Valley (hereafter, the Valley), WV, in spatial and temporal contexts, I reviewed general trends in climate, environment, technology, and society through the major periods of prehistory. A network of trails integrated the people of the Valley area within broader regional trends. Based on the widespread patterns, inferences of local environments and natural resources, and findings at local archeological sites-including recently discovered prehistoric artifacts in the Valley-I synthesized a general theory about the ecology of prehistoric people of the Valley area: from settlements in optimal habitats of the Cheat and/or South Branch Potomac River floodplains, people occupied the sub-optimal habitat of the Valley for extended stays (e.g., one or two months) during annual migrations, for brief stopovers (one or two days) while central-place foraging, or both. From this general model, I derived several specific hypotheses, most of which are testable with current archaeological methods. I conclude by comparing the environmental ethics of prehistoric and modern inhabitants of the Valley. This review will help residents and visitors appreciate the Valley's prehistoric forerunners, commercial developers minimize archaeological impacts, and public land managers design interpretive exhibits.

Emanuel R.E.,Appalachian State University | Emanuel R.E.,North Carolina State University | Epstein H.E.,University of Virginia | McGlynn B.L.,Montana State University | And 3 more authors.
Water Resources Research | Year: 2010

Vegetation water stress plays an important role in the movement of water through the soil-plant-atmosphere continuum. However, the effects of water stress on evapotranspiration (ET) and other hydrological processes at the watershed scale remain poorly understood due in part to spatially and temporally heterogeneous conditions within the watershed, especially in areas of mountainous terrain. We used a spatially distributed model to understand and evaluate the relationship between water stress and ET in a forested mountain watershed during the snow-free growing season. Vegetation water stress increased as the growing season progressed, due to continued drying of soils, and persisted late into the growing season, even as vapor pressure deficit decreased with lower temperatures. As a result, ET became decoupled from vapor pressure deficit and became increasingly dependent on soil moisture later in the growing season, shifting from demand limitation to supply limitation. We found water stress and total growing season ET to be distributed nonuniformly across the watershed due to interactions between topography and vegetation. Areas having tall vegetation and low topographic index experienced the greatest water stress, yet they had some of the highest evapotranspiration rates in the watershed. Copyright 2010 by the American Geophysical Union.

Pacific V.J.,Montana State University | McGlynn B.L.,Montana State University | Riveros-Iregui D.A.,University of Nebraska - Lincoln | Welsch D.L.,Canaan Valley Institute | Epstein H.E.,University of Virginia
Hydrological Processes | Year: 2011

Variability in soil respiration at various spatial and temporal scales has been the focus of much research over the last decade aimed to improve our understanding and parameterization of physical and environmental controls on this flux. However, few studies have assessed the control of landscape position and groundwater table dynamics on the spatiotemporal variability of soil respiration. We investigated growing season soil respiration in a ∼393 ha subalpine watershed in Montana across eight riparian-hillslope transitions that differed in slope, upslope accumulated area (UAA), aspect, and groundwater table dynamics. We collected daily-to-weekly measurements of soil water content (SWC), soil temperature, soil CO2 concentrations, surface CO2 efflux, and groundwater table depth, as well as soil C and N concentrations at 32 locations from June to August 2005. Instantaneous soil surface CO2 efflux was not significantly different within or among riparian and hillslope zones at monthly timescales. However, cumulative integration of CO2 efflux during the 83-day growing season showed that efflux in the wetter riparian zones was ∼25% greater than in the adjacent drier hillslopes. Furthermore, greater cumulative growing season efflux occurred in areas with high UAA and gentle slopes, where groundwater tables were higher and more persistent. Our findings reveal the influence of landscape position and groundwater table dynamics on riparian versus hillslope soil CO2 efflux and the importance of time integration for assessment of soil CO2 dynamics, which is critical for landscape-scale simulation and modelling of soil CO2 efflux in complex landscapes. © 2010 John Wiley & Sons, Ltd.

Riveros-Iregui D.A.,University of Nebraska - Lincoln | McGlynn B.L.,Montana State University | Marshall L.A.,Montana State University | Welsch D.L.,Canaan Valley Institute | And 3 more authors.
Water Resources Research | Year: 2011

Growing season soil CO2 efflux is known to vary laterally by as much as seven fold within small subalpine watersheds (<5 km2), and such degree of variability has been strongly related to the landscape-imposed redistribution of soil water. Current empirical or process models offer low potential to simulate this variability or to simulate watershed-scale dynamics of soil CO2 efflux. We modified an existing process soil CO 2 production and efflux model to include spatially variable soil moisture, and applied it to a well-studied and moderately complex watershed of the northern Rocky Mountains. We started at the point scale and progressively modeled processes up to the watershed scale. We corroborated model performance using an independent data set of soil CO2 efflux measurements from 53 sites distributed across the 393 ha watershed. Our approach (1) simulated the seasonality of soil CO2 efflux at riparian sites; (2) reproduced short-term (diel) dynamics of soil CO2 concentration ([CO 2]) at riparian sites, particularly observed hysteresis patterns in the soil [CO2]-soil temperature relationship; and (3) simulated growing season estimates of soil CO2 efflux at dry sites across the landscape (98% of area). Model limitations included poor simulation of growing season (cumulative) soil CO2 efflux at sites with a large drainage area, likely as a result of poorly modeled soil water content and challenges in parametrization of root and microbial activities. Our study provides important insight into coupling hydrological and biogeochemical models at landscape scales, and highlights the role of landscape structure and heterogeneity when modeling spatial variability of biogeochemical processes. © 2011 by the American Geophysical Union.

Griscom B.,The Nature Conservancy | Griscom H.,James Madison University | Deacon S.,Canaan Valley Institute
Restoration Ecology | Year: 2011

Herbaceous competition and herbivory have been identified as critical barriers to restoration of native tree species in degraded landscapes around the world; however, the combined effects of competition and herbivory are poorly understood. We experimentally manipulated levels of herbivory and herbaceous competition and analyzed the response of tree seedling performance over three growing seasons as a function of species and habitat in north-central West Virginia. Four native tree species were planted in old field and forest experimental plots: Castanea dentata (American chestnut), Quercus rubra (red oak), Acer saccharum (sugar maple), and Picea rubens (red spruce). Red spruce demonstrated the highest growth increment and greatest survival (64%) and most consistent results among treatments and habitats. Red spruce survival was not reduced in the presence of Odocoileus virginianus (white-tailed deer) browse and herbaceous competition; however, growth was improved by suppression of herbaceous competition. We suspect that this deciduous forest landscape would regenerate to a red spruce dominated forest if seed source was available. In contrast, the other three species tested had very low survival when exposed to deer and were more responsive to competing vegetation and habitat type. American chestnut had low survival and growth across all treatments, suggesting basic climate limitations. Vigorous natural regeneration of Prunus serotina (black cherry) occurred in forest plots where both competing herbs and deer were excluded. Our results demonstrated the importance of testing multiple potential recruitment barriers and species at once and the need for species and habitat-specific restoration treatments. © 2010 Society for Ecological Restoration International.

Discover hidden collaborations