Midsummer Standing Crops of Wetland Sedge Meadows Along a Transect from Forest to Prairie

Midsummer standing crops of wetland sedges have been measured along a transect from forest to prairie in northwestern Minnesota. The eight forest stands, all but one on waterlogged fibrous peats, are dominated by Carex lacustris (4 stands), C. lasiocarpa (2), C. rostrata (1) and C. atherodes (1). They exhibit above-ground standing crops ranging from 425 to 738 g dry wt/m2, with a mean of 606 g/m2. The five prairie stands on well-drained silty peats are all dominated by Carex atherodes, and their standing crops range from 679 to 1248 g dry wt/m2, with a mean of 941 g/m2. Above-ground standing crop in the prairie sites is therefore 55% greater than in the forest sites

Influence of Soil Acidity on the Occurrence of Athiorhodaceae

Enrichment cultures from strongly acid Sphagnum bog peats and moderately acid to circumneutral fen peats revealed Athiorhodaceae to be present in almost all suitably wet samples above pH 5.3 and absent from almost all samples below pH 4.7. These bacteria were recorded in only one of fifty cultures from acid humus layers in a jack pine forest, and in none of thirty cultures from moderately acid humus layers in a mixed woodland. They were also absent from old-field surface soils, which often contained considerable amounts of organic litter

Midsummer Standing Crops of Wetland Sedge Meadows Along a Transect from Forest to Prairie

Midsummer standing crops of wetland sedges have been measured along a transect from forest to prairie in northwestern Minnesota. The eight forest stands, all but one on waterlogged fibrous peats, are dominated by Carex lacustris (4 stands), C. lasiocarpa (2), C. rostrata (1) and C. atherodes (1). They exhibit above-ground standing crops ranging from 425 to 738 g dry wt/m2, with a mean of 606 g/m2. The five prairie stands on well-drained silty peats are all dominated by Carex atherodes, and their standing crops range from 679 to 1248 g dry wt/m2, with a mean of 941 g/m2. Above-ground standing crop in the prairie sites is therefore 55% greater than in the forest sites

Influence of Soil Acidity on the Occurrence of Athiorhodaceae

Enrichment cultures from strongly acid Sphagnum bog peats and moderately acid to circumneutral fen peats revealed Athiorhodaceae to be present in almost all suitably wet samples above pH 5.3 and absent from almost all samples below pH 4.7. These bacteria were recorded in only one of fifty cultures from acid humus layers in a jack pine forest, and in none of thirty cultures from moderately acid humus layers in a mixed woodland. They were also absent from old-field surface soils, which often contained considerable amounts of organic litter

The value of paleoecology as an aid to monitoring ecosystems and landscapes, chiefly with reference to North America

Paleoecological indicators are examined as to their accuracy in reconstructing past biotic communities and environmental conditions, their utility in answering important questions about such communities and conditions, and the temporal and spatial scales over which they are effective. Next, environmental problems susceptible of paleoecological analysis are considered, as are the ecosystem and landscape properties that can be inferred from such an analysis. The usefulness of paleoecology in anticipating ecological surprises is then discussed. Finally, a set of conclusions and recommendations is presented

Reflections on the Life in a Deteriorating World: How Chance Made Me an Environmental Activist

Full Text PDFThis memoir describes how I, a young scientist who believed that "applied science" was second-rate science, found myself -- by chance and serendipity -- studying the ecological consequences of acid rain and radioactive fallout, purely as fascinating phenomena and without thought of mitigation. As I continued with their study and taught students about them, I became more and more aware of their significance for society, so that after twenty years -- and again by chance and serendipity – I became an environmental activist. Since then I have testified about environmental deterioration, attended scientific committees and workshops, and advocated for pollution control in both academic and societal settings

Four Poems About the Natural World

Full text PDFThese poems were written in the 1970’s, inspired especially by the English poet Kathleen Raine, a Cambridge M.A. in botany and zoology with a strong focus on the natural world. Soon I was asked by my friend Professor Dennis Hurrell to speak to a class on Women’s Literature entitled “Form and Function in Literature” and to provide a contrast by focusing on “Form and Function in the Biosphere.” In doing so, I read and described the significance of a set of poems that had an ecological context, and slipped in a couple of my own