Forest Communities of the Great Valley of East Tennessee and Their Relationship to Soil and Topographic Properties

The complex physiographic and climatic history of the Great Valley of East Tennessee has resulted in development of diverse alternating ridge and valley land forms and soils which provide equally diverse forest habitats. The objectives of this study were (1) to quantify certain topographic features, (2) to analyze statistical relationships of vegetation and tree taxa to selected soil properties and topographic features, (3) to assess magnitude and predictability of these relationships, (4) to document taxonomic diversity of tree taxa, (5) to document and delimit contemporary forest communities and describe interactions with soil-site properties, and (6) to consider relationships of these communities to other forests of the Southern Appalachians. In all, 684 concentric 1/10- and 1/100-acre temporary, circular plots were established among 58 old-growth forest stands; plot number varied with stand size. On 1/10-acre plots, trees 5 in. dbh and greater were measured and recorded and stumps of Castanea dentata were counted. On 1/100-acre plots, trees less than 5 in. dbh were recorded by taxon. At each plot, slope characteristics were recorded. Within 34 stands, soil samples were collected and physical properties were described. Properties determined in the field were thickness of A and B horizons, stone percent, pedon and mottling depth. Laboratory analysis included pH and textural determinations for each horizon; available water was calculated from published data. Topographic properties were quantified by field measurement and determinations from topographic maps. These included slope angle and aspect, calculation of slope form by width/depth ratios of concavities and convexities, slope position by relative relief, size of ridge and valley units, external protection afforded by adjacent land forms, and local relief. Statistical analyses included simple linear correlations among soil and site properties and tree taxa. Linear models were as informative as logarithmic models. Stepwise multiple regression was used to predict relationships of relative density, relative basal area and importance value of selected overstory tree taxa to selected soil and topographic properties; quadratic and interaction terms of independent variables were also employed. Soil and site correlations showed several interrelationships. Soil separates were frequently intercorrelated. Soil depth and stone content are two important variables controlling water availability in this area. Local relief and topographic length and width were frequently correlated with site variables; ecological significance is indirect and other on-site characteristics must be considered concomitantly. Correlations between slope angle and soil properties were the most important soil-topography interactions. Stepwise regression analysis indicated that vegetation and values of overstory tree taxa were not easily predicted. Total density, total basal area, and values of oak, hickory and pine taxa had R2 values of 0.10 or less. Three taxa had R2 values of 0.25. Equations for Fagus grandifolia had the highest predictive values. Topographic characteristics accounted for more variation among taxa than soil properties. The most important soil variable predicting importance of various taxa was water availability. Other commonly correlated soil variables made limited contributions. Interaction and quadratic terms of independent variables were of limited value. Genetic variability among taxa, inherent differences among soils, low precision and accuracy in measuring soil characteristics, omission of important environmental parameters, and unknown stand histories were considered factors contributing to low predictability. Forest communities recognized were associated with soil-parent material units of ridges and valleys. Overstory density was 110 ± 30 stems per acre; basal area was approximately 100 ± 40 ft.2 per acre. Of the 57 tree taxa recognized, the majority was widely distributed in deciduous forests; oak and hickory taxa comprised 30 percent. Four vegetation complexes were recognized as the central core of forest development. The White Oak complex, comprised of the largest number of communities, is largest in aerial extent. The dominant or co-dominant, Quercus alba, appears to have the greatest ecological amplitude of any taxon in this area. Chestnut Oak, Mixed Mesophytic and Tulip Poplar Complexes and pine, restricted upland oak, and bottomland hardwood communities were also recognized. Major taxa that apparently replace Castanea dentata are Quercus prinus and/or Quercus alba

Some Relationships of Vegetation to Soil and Site Factors on Wilson Mountain, Morgan County, Tennessee

INTRODUCTION In this study, the forest composition of Wilson Mountain, Morgan County, Tennessee, is described and distribution of tree taxa and site factors are related. The study arose from the need for geographic knowledge of an area where resource understanding is of great national concern, and to provide data for characterization of local forest and soil resources as an aid in their management. Of further interest is characterization of the genetic and ecological amplitude of forest tree taxa in this area close to the center of Deciduous Forest diversity. The objectives in this study of the vegetation of Wilson Mountain were: (a) to describe the pattern of tree communities, (b) to analyze the variation in environmental factors which may be responsible for the distribution of tree taxa, (c) to evaluate the degree of correlation between environmental factors and vegetational pattern, (d) to determine if variation in characteristics of overstory and understory tree taxa was related to soil characteristics, slope direction and (or) topography. Tree vegetation occupying approximately 830 acres of Wilson Mountain was sampled during the summer months of 1965

CUMBRIA (Reino Unido) (Inglaterra). Central. Mapas generales (1789). 1:65400

Comprende la zona central del condado inglés de CumbriaEscala gráfica de 5 millas [= 12,3 cm]. Coordenadas de la ciudad de Keswick, referidas, al parecer, al meridiano de Greenwich (O 3°01'30''/N 54°03'30''). Orientado con lis en rosa de ocho vientosOrografía a trazosTítulo enmarcado en un paisaje montañosoForma parte de la Colección Mendoz

Selenium-Modified TiO2 and Its Impact on Photocatalysis

This work describes the preparation of a selenium-modified TiO2 photocatalyst and a preliminary evaluation of its photocatalytic activity. Se-TiO2 displayed greater visible absorption than undoped TiO2 and was still capable of degrading quinoline at a slightly faster rate than undoped TiO2 under UV light. Se-TiO2 was also able to degrade organic molecules under purely visible light by a single electron transfer pathway. Irradiation with \u3e435 nm light showed no evidence of efficient production of HO•-like species. Se-TiO2 was also examined under hypoxic conditions, where the Se atoms were capable of trapping photogenerated electrons as evidenced by XPS

The physical science behind climate change

For a scientist studying climate change, 'eureka' moments are unusually rare. Instead progress is generally made by a painstaking piecing together of evidence from every new temperature measurement, satellite sounding or climate-model experiment. Data get checked and rechecked, ideas tested over and over again. Do the observations fit the predicted changes? Could there be some alternative explanation? Good climate scientists, like all good scientists, want to ensure that the highest standards of proof apply to everything they discover. And the evidence of change has mounted as climate records have grown longer, as our understanding of the climate system has improved and as climate models have become ever more reliable. Over the past 20 years, evidence that humans are affecting the climate has accumulated inexorably, and with it has come ever greater certainty across the scientific community in the reality of recent climate change and the potential for much greater change in the future. This increased certainty is starkly reflected in the latest report of the Intergovernmental Panel on Climate Change (IPCC), the fourth in a series of assessments of the state of knowledge on the topic, written and reviewed by hundreds of scientists worldwide. The panel released a condensed version of the first part of the report, on the physical science basis of climate change, in February. Called the 'Summary for Policymakers,' it delivered to policymakers and ordinary people alike an unambiguous message: scientists are more confident than ever that humans have interfered with the climate and that further human-induced climate change is on the way. Although the report finds that some of these further changes are now inevitable, its analysis also confirms that the future, particularly in the longer term, remains largely in our hands--the magnitude of expected change depends on what humans choose to do about greenhouse gas emissions. The physical science assessment focuses on four topics: drivers of climate change, changes observed in the climate system, understanding cause-and-effect relationships, and projection of future changes. Important advances in research into all these areas have occurred since the IPCC assessment in 2001. In the pages that follow, we lay out the key findings that document the extent of change and that point to the unavoidable conclusion that human activity is driving it

SCOPE New Photographic Practices

The photographic practices brought together for this exhibition and publication provide a broad scope of how photographic and lens based media may be used in order to have a visceral and conceptual impact. The methods on show demonstrate the way that artists might pick and choose from the approaches, processes and debates that have arisen through the medium’s history. This collection of work features film, video and photography that demand a renegotiation of the relationship between camera, subject and viewer. Visual Art Centre Gallery, Tsinghua University, Beijing, Chin

Complete Hemodynamic Profiling With Pulmonary Artery Catheters in Cardiogenic Shock Is Associated With Lower In-Hospital Mortality

OBJECTIVES: The purpose of this study was to investigate the association between obtaining hemodynamic data from early pulmonary artery catheter (PAC) placement and outcomes in cardiogenic shock (CS). BACKGROUND: Although PACs are used to guide CS management decisions, evidence supporting their optimal use in CS is lacking. METHODS: The Cardiogenic Shock Working Group (CSWG) collected retrospective data in CS patients from 8 tertiary care institutions from 2016 to 2019. Patients were divided by Society for Cardiovascular Angiography and Interventions (SCAI) stages and outcomes analyzed by the PAC-use group (no PAC data, incomplete PAC data, complete PAC data) prior to initiating mechanical circulatory support (MCS). RESULTS: Of 1,414 patients with CS analyzed, 1,025 (72.5%) were male, and 494 (34.9%) presented with myocardial infarction; 758 (53.6%) were in SCAI Stage D shock, and 263 (18.6%) were in Stage C shock. Temporary MCS devices were used in 1,190 (84%) of those in advanced CS stages. PAC data were not obtained in 216 patients (18%) prior to MCS, whereas 598 patients (42%) had complete hemodynamic data. Mortality differed significantly between PAC-use groups within the overall cohort (p \u3c 0.001), and each SCAI Stage subcohort (Stage C: p = 0.03; Stage D: p = 0.05; Stage E: p = 0.02). The complete PAC assessment group had the lowest in-hospital mortality than the other groups across all SCAI stages. Having no PAC assessment was associated with higher in-hospital mortality than complete PAC assessment in the overall cohort (adjusted odds ratio: 1.57; 95% confidence interval: 1.06 to 2.33). CONCLUSIONS: The CSWG is a large multicenter registry representing real-world patients with CS in the contemporary MCS era. Use of complete PAC-derived hemodynamic data prior to MCS initiation is associated with improved survival from CS

Challenges in quantifying changes in the global water cycle

Human influences have likely already impacted the large-scale water cycle but natural variability and observational uncertainty are substantial. It is essential to maintain and improve observational capabilities to better characterize changes. Understanding observed changes to the global water cycle is key to predicting future climate changes and their impacts. While many datasets document crucial variables such as precipitation, ocean salinity, runoff, and humidity, most are uncertain for determining long-term changes. In situ networks provide long time-series over land but are sparse in many regions, particularly the tropics. Satellite and reanalysis datasets provide global coverage, but their long-term stability is lacking. However, comparisons of changes among related variables can give insights into the robustness of observed changes. For example, ocean salinity, interpreted with an understanding of ocean processes, can help cross-validate precipitation. Observational evidence for human influences on the water cycle is emerging, but uncertainties resulting from internal variability and observational errors are too large to determine whether the observed and simulated changes are consistent. Improvements to the in situ and satellite observing networks that monitor the changing water cycle are required, yet continued data coverage is threatened by funding reductions. Uncertainty both in the role of anthropogenic aerosols, and due to large climate variability presently limits confidence in attribution of observed changes