Microbial and chemical markers: runoff transfer in animal manure-amended soils

Fecal contamination of water resources is evaluated by the enumeration of the fecal coliforms and Enterococci. However, the enumeration of these indicators does not allow us to differentiate between the sources of fecal contamination. Therefore, it is important to use alternative indicators of fecal contamination to identify livestock contamination in surface waters. The concentration of fecal indicators (, enteroccoci, and F-specific bacteriophages), microbiological markers (Rum-2-bac, Pig-2-bac, and ), and chemical fingerprints (sterols and stanols and other chemical compounds analyzed by 3D-fluorescence excitation-matrix spectroscopy) were determined in runoff waters generated by an artificial rainfall simulator. Three replicate plot experiments were conducted with swine slurry and cattle manure at agronomic nitrogen application rates. Low amounts of bacterial indicators (1.9-4.7%) are released in runoff water from swine-slurry-amended soils, whereas greater amounts (1.1-28.3%) of these indicators are released in runoff water from cattle-manure-amended soils. Microbial and chemical markers from animal manure were transferred to runoff water, allowing discrimination between swine and cattle fecal contamination in the environment via runoff after manure spreading. Host-specific bacterial and chemical markers were quantified for the first time in runoff waters samples after the experimental spreading of swine slurry or cattle manure.     

Discourses of Place: Environmental Interpretation about Vermont Forests

Motivated by a lack of scholarly attention to the substance of interpretive messages and materials, this study examines discursive aspects of interpretative brochures available at forest recreation and tourism sites in Vermont, United States. Directive statements that instruct and guide visitor experiences—and the discourses to which they contribute—were analyzed for content, form, and meaning. Across the interpretive brochures, four broad discourses were identified: the natural forest, the recreational forest, the productive forest, and the dependent forest. Consideration of intertextuality revealed a fifth, hybrid discourse that linked forests to meanings of Vermont as a distinctive place. The convergence of these discourses across the set of brochures gives insight into the ways interpretation serves to both direct individual visitor experiences at particular sites, and to influence the development of larger-scale place meanings.     

Spectroscopic and molecular characterization of humic substances (HS) from soils and sediments in a watershed: comparative study of HS chemical fractions and the origins

Environmental Science and Pollution Research - Optical properties and molecular composition of humic substances (HS) can provide valuable information on the sources and the history of the...