Thesis (M.S.)--University of Wisconsin--Madison. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 121-124).

Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 99-100).

Thesis (Ph. D.)--University of Louisville, 2009. / Department of Teaching and Learning. Vita. "August 2009." Includes bibliographical references (leaves 304-320).

Thesis (M.S.)--Ohio University, June, 2009. / Title from PDF t.p. Includes bibliographical references.

Universiẗat, Diss., 2004--Bonn.

The Rio Gavilan watershed, located in Mexico 's northern Sierra Madre Occidental , has significance in conservation history. Upon visiting the remote, largely un­developed watershed during two hunting trips in the 1930s, renowned conservationist Aldo Leopold thought it was the best picture of land health he had seen. His main indicators of healthy land were slow water runoff rates regulating erosion and historical predator-prey relationships. The visits confirmed Leopold's concept of land health, inspired many of his essays, and helped shape his land ethic. Leopold proposed the area as a control site to research healthy land throughout North America . The proposal never went forward and the area has since been more intensively logged and grazed. This dissertation research used extensive literature review, archives, oral histories, citizen surveys, and rapid assessment of forest, rangeland, riparian, and socioeconomic health to assess impacts of past cultures and update the area's land health status. Projects that could restore land health, such as linked eco-tourism, forest density reduction, and rotational grazing, were assessed for feasibility. Recent critiques of Leopold's land ethic were also reviewed. Results indicate most pre-1940s impacts were light, current land health status is moderate, and local interest exists in restoring land health. Many fish and wildlife populations are reduced, temporarily stabilized, but still at risk. Soil and riverbed erosion, service sector economics, and (at some ridge-top sites) forest density are the land health indicators in worst condition. Land health restoration projects are feasible.

Dénonçant dès le début de sa carrière une dégradation catastrophique de la fertilité des sols, de la diversité biologique et de la disponibilité de l'eau douce au sud-ouest des États-Unis, Aldo Leopold propose une nouvelle voie originale pour le mouvement de conservation de la nature. Il développe une éthique de la terre qui redonne sa juste part de responsabilité aux propriétaires privés, qui doivent viser un usage de la terre en harmonie avec celle-ci. De ce point de vue, l'éthique de la terre semble tout indiquée pour guider un usage écologique de la terre qu'on cultive. En effet, la terre en usage agricole est à l'intersection de l'humanité et la nature. Toutefois, John Baird Callicott, commentateur et ardent défenseur de la valeur philosophique de l'éthique de la terre de Leopold, a peu traité de la posture de ce dernier sur l'agriculture. Paul B. Thompson accuse non seulement Callicott, mais la plupart des philosophes de l'environnement américains de se désintéresser des questions agricoles, au moins jusqu'à la décennie 1990. Quelle est la source de ce divorce apparent entre l'agriculture et l'éthique environnementale ? Comment l'éthique de la terre de Leopold peut-elle guider un usage des terres qu'on cultive ? En réexaminant les textes de Leopold, sa conception de la terre comme communauté biotique, sa maxime morale de l'éthique de la terre et son idéal du *husbandry*, on voit se dessiner un ensemble de savoirs et de savoir-faire qui construisent une relation riche à la terre. À travers le regard de Leopold, un regard aiguisé par l'immersion dans la communauté biotique, on aperçoit une esquisse d'une agriculture biotique et d'une éthique de la terre qu'on cultive. / Early in his career, Aldo Leopold exposes a catastrophic degradation of soil fertility, biological diversity and freshwater availability in the southwestern United States. Many years later, he suggests a new path forward for the nature conservation movement, a land ethic that hands back their share of responsibilities to private landowners, who must aim for harmony between man and land. In this perspective, a land ethic could be a promising way to guide an ecological use of agricultural land. Indeed, farmland is at the intersection of humanity and nature. However, John Baird Callicott, who passionately advocated the philosophical value of Leopold's land ethic, wrote very little about Leopold's stance on agriculture. Paul B. Thompson accuses not only Callicott, but most American environmental philosophers of showing little to no interest to agricultural issues, at least until de 1990s. How can the apparent chasm between agriculture and environmental ethics be explained? How can Leopold's land ethic guide our use of agricultural land? By re-examining Leopold's texts, his concept of land as a biotic community, the land ethic moral maxim and his ideal of husbandry, we begin to understand how the right knowledge and know-how leads us to a closer and richer relationship to land. Through Leopold's gaze, a gaze sharpened by immersion in the biotic community, we begin to see a sketch of a biotic agriculture and of a land ethic applied to agriculture.