682 research outputs found

    Measuring and modeling near-surface reflected and emitted radiation fluxes at the FIFE site

    Get PDF
    Information is presented pertaining to the measurement and estimation of reflected and emitted components of the radiation balance. Information is included about reflectance and transmittance of solar radiation from and through the leaves of some grass and forb prairie species, bidirectional reflectance from a prairie canopy is discussed and measured and estimated fluxes are described of incoming and outgoing longwave and shortwave radiation. Results of the study showed only very small differences in reflectances and transmittances for the adaxial and abaxial surfaces of grass species in the visible and infrared wavebands, but some differences in the infrared wavebands were noted for the forbs. Reflectance from the prairie canopy changed as a function of solar and view zenith angles in the solar principal plane with definite asymmetry about nadir. The surface temperature of prairie canopies was found to vary by as much as 5 C depending on view zenith and azimuth position and on the solar azimuth. Aerodynamic temperature calculated from measured sensible heat fluxes ranged from 0 to 3 C higher than nadir-viewed temperatures. Models were developed to estimate incoming and reflected shortwave radiation from data collected with a Barnes Modular Multiband Radiometer. Several algorithms for estimating incoming longwave radiation were evaluated and compared to actual measures of that parameter. Net radiation was calculated using the estimated components of the shortwave radiation streams, determined from the algorithms developed, and from the longwave radiation streams provided by the Brunt, modified Deacon, and the Stefan-Boltzmann models. Estimates of net radiation were compared to measured values and found to be within the measurement error of the net radiometers used in the study

    Estimating carbon stock change in agroforestry and family forestry practices

    Get PDF
    Paper presented at the 11th North American Agroforesty Conference, which was held May 31-June 3, 2009 in Columbia, Missouri.In Gold, M.A. and M.M. Hall, eds. Agroforestry Comes of Age: Putting Science into Practice. Proceedings, 11th North American Agroforestry Conference, Columbia, Mo., May 31-June 3, 2009.The Carbon Management Evaluation Tool for Voluntary Reporting (COMET-VR) is an online tool that estimates short-term carbon stock (CS) changes under different farm or forest land management systems, including temperate agroforestry practices. It was developed by the USDA Natural Resources Conservation Service in conjunction with Colorado State University. The intended audience includes private farm and forest landowners, NRCS field staff, and technical service providers. Through the online interface, users identify their location, parcel size, surface soil texture, crop rotation history and tillage intensity. The user can choose either of two methods to estimate CS change for their agroforestry practice: 1) for new or future plantings, by using standard prescriptions common to their geographic region, or 2) for a more accurate estimate of an existing planting, by using a summary of live-tree stand inventory data collected from their parcel. Above and below-ground individual tree biomass is calculated using diameter-based allometric equations generalized for tree genera groups. For existing agroforestry plantings, growth estimates are based on empirical models developed from forest inventory data specific to species and region. For new or future plantings, growth estimates were derived for standard agroforestry prescriptions using the Forest Vegetation Simulator. COMET-VR uses the Century soil carbon model to estimate CS change in soil. The output of the tool is a report estimating CS changes over the forthcoming 10 years in the above and below-ground portions of live trees and in the soil. Although specifically designed to meet the requirements of the US Dept. of Energy voluntary greenhouse gas reporting program, COMET-VR may also be applicable to other private and public sector carbon offset programs.Miles L. Merwin (1), Mark Easter (2), Lyn R. Townsend (1), Roel C. Vining (1) and Greg L. Johnson (1) ; 1. USDA Natural Resources Conservation Service, 1201 NE Lloyd Blvd., Portland, OR 97232. 2. Natural Resource Ecology Laboratory, Colorado State University, Ft. Collins, CO.Includes bibliographical references

    Bringing Habits and Emotions into Food Waste Behaviour

    Get PDF
    This study examined consumer food waste behaviour using a comprehensive model integrating the theory of planned behaviour (TPB), the theory of interpersonal behaviour, and the comprehensive model of environmental behaviour. Using a temporally lagged design, one hundred and seventy-two respondents answered four questionnaires over a period of 14 months. Questionnaires measured emotions in relation to food waste, habits, the TPB variables, intention to reduce food waste, and self-reported food waste behaviour. Results showed that the less well-studied variables of habits and emotions were important determinants of participants’ intentions to reduce food waste and their current food waste behaviour. As expected, we found that negative emotions were associated with greater intentions to reduce food waste, but contrary to our predictions they were also associated with higher levels of food waste behaviour. In other words, participants who experienced more negative emotion when thinking about food waste intended to reduce their waste but actually ended up wasting more food. Results also show that participants with a greater sense of control, and more normative support for reducing food waste also had stronger intentions to engage in the behaviour. Our findings extend existing understanding and underscore the importance of the non-cognitive determinants of behaviour, namely emotions and habits. The implications for research and practice are discussed

    B844: Checklist of the Vascular Plants of Maine Third Revision

    Get PDF
    This is the third revision of the Checklist of Vascular Plants of Maine. Like its predecessors, it lists all ferns and related plants, conifers, and flowering plants native and naturalized in Maine and records their county-level distribution in the state. The first Check- list (Ogden et al. 1948) was based on specimens in herbaria at the University of Maine (hereafter referred to as MAINE), Portland Society of Natural History, New England Botanical Club, Gray Herbarium of Harvard University, and the private collection of Glen D. Chamberlain of Presque Isle, Maine (now part of MAINE). Bean et al. (1966) revised the checklist to include additions to the flora and update the nomenclature to follow Fernald (1950). Richards et al. (1983) added many new state and county records in the second revision. The purpose of this revision is twofold. First, we have included many new county and state records. Since Richards et al. (1983) there has been considerable collecting in Maine, much of it directed at searching for new state and county records in relatively neglected regions of the state. Second, there have been numerous changes in the scientific names of Maine plants since Fernald (1950), the nomenclatural basis of Richards et al. (1983). We have largely followed Kartesz\u27s (1994) nomenclature (see Taxonomy and Nomenclature section). Recent work on rare plants and establishment of an official list of endangered and threatened plants in Maine (Dibble et al. 1989; Maine State Planning Office 1990) also motivate updating the known distribution and taxonomy of Maine\u27s flora.https://digitalcommons.library.umaine.edu/aes_bulletin/1121/thumbnail.jp

    Life in 2.5D: Animal Movement in the Trees

    Get PDF
    The complex, interconnected, and non-contiguous nature of canopy environments present unique cognitive, locomotor, and sensory challenges to their animal inhabitants. Animal movement through forest canopies is constrained; unlike most aquatic or aerial habitats, the three-dimensional space of a forest canopy is not fully realized or available to the animals within it. Determining how the unique constraints of arboreal habitats shape the ecology and evolution of canopy-dwelling animals is key to fully understanding forest ecosystems. With emerging technologies, there is now the opportunity to quantify and map tree connectivity, and to embed the fine-scale horizontal and vertical position of moving animals into these networks of branching pathways. Integrating detailed multi-dimensional habitat structure and animal movement data will enable us to see the world from the perspective of an arboreal animal. This synthesis will shed light on fundamental aspects of arboreal animals’ cognition and ecology, including how they navigate landscapes of risk and reward and weigh energetic trade-offs, as well as how their environment shapes their spatial cognition and their social dynamics

    30 days wild: development and evaluation of a large-scale nature engagement campaign to improve well-being

    Get PDF
    There is a need to increase people’s engagement with and connection to nature, both for human well-being and the conservation of nature itself. In order to suggest ways for people to engage with nature and create a wider social context to normalise nature engagement, The Wildlife Trusts developed a mass engagement campaign, 30 Days Wild. The campaign asked people to engage with nature every day for a month. 12,400 people signed up for 30 Days Wild via an online sign-up with an estimated 18,500 taking part overall, resulting in an estimated 300,000 engagements with nature by participants. Samples of those taking part were found to have sustained increases in happiness, health, connection to nature and pro-nature behaviours. With the improvement in health being predicted by the improvement in happiness, this relationship was mediated by the change in connection to nature

    From thermal rectifiers to thermoelectric devices

    Full text link
    We discuss thermal rectification and thermoelectric energy conversion from the perspective of nonequilibrium statistical mechanics and dynamical systems theory. After preliminary considerations on the dynamical foundations of the phenomenological Fourier law in classical and quantum mechanics, we illustrate ways to control the phononic heat flow and design thermal diodes. Finally, we consider the coupled transport of heat and charge and discuss several general mechanisms for optimizing the figure of merit of thermoelectric efficiency.Comment: 42 pages, 22 figures, review paper, to appear in the Springer Lecture Notes in Physics volume "Thermal transport in low dimensions: from statistical physics to nanoscale heat transfer" (S. Lepri ed.
    corecore