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Brian G. Wolff

Bio: Brian G. Wolff is an academic researcher from University of Minnesota. The author has contributed to research in topics: Agriculture & Agricultural productivity. The author has an hindex of 4, co-authored 4 publications receiving 3342 citations.

Papers
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Journal ArticleDOI
13 Apr 2001-Science
TL;DR: Should past dependences of the global environmental impacts of agriculture on human population and consumption continue, 109 hectares of natural ecosystems would be converted to agriculture by 2050, accompanied by 2.4- to 2.7-fold increases in nitrogen- and phosphorus-driven eutrophication of terrestrial, freshwater, and near-shore marine ecosystems.
Abstract: During the next 50 years, which is likely to be the final period of rapid agricultural expansion, demand for food by a wealthier and 50% larger global population will be a major driver of global environmental change. Should past dependences of the global environmental impacts of agriculture on human population and consumption continue, 10(9) hectares of natural ecosystems would be converted to agriculture by 2050. This would be accompanied by 2.4- to 2.7-fold increases in nitrogen- and phosphorus-driven eutrophication of terrestrial, freshwater, and near-shore marine ecosystems, and comparable increases in pesticide use. This eutrophication and habitat destruction would cause unprecedented ecosystem simplification, loss of ecosystem services, and species extinctions. Significant scientific advances and regulatory, technological, and policy changes are needed to control the environmental impacts of agricultural expansion.

3,606 citations

01 Jan 2010
TL;DR: This paper examined the relationship between student participation in asynchronous online discussions and final exam scores via regression and non-parametric analyses and found that participation was a statistically significant predictor of final exam score and course completion rates.
Abstract: Many online courses require participation in asynchronous online discussions. While various studies aimed at measuring the efficacy of these discussions indicate that participation enhances learning, course design consultants commonly warn instructors to avoid schemes that could foster excessive student participation. Excessive participation should be of concern, for example, if students are likely to be distracted from more important coursework. The authors examine the relationship between student participation in asynchronous online discussions and final exam scores via regression and non-parametric analyses. Participation was determined to be a statistically significant predictor of final exam scores and course completion rates. No indication was found that participation, even at the most robust levels encountered (posting >19,000 words per semester), interferes with learning.

12 citations

Journal ArticleDOI
TL;DR: Al impaired reproduction in Japanese quail Coturnix coturnix japonica at concentrations below those observed in aquatic insects emerging from that lake and increasing dietary Ca and P was found to mitigate this effect.
Abstract: Aluminum leached from granitic rocks by acidic precipitation has been implicated as a cause of reproductive failure in insectivorous passeriformes. Aluminum in emerging aquatic insects has been linked to elevated skeletal Al and reproductive failure in Pied Flycatchers Ficedula hypoleuca nesting near an acidified Swedish lake. In this study, Al impaired reproduction in Japanese quail Coturnix coturnix japonica at concentrations below those observed in aquatic insects emerging from that lake. Aluminum citrate was added to the diet of 65-day-old quail to obtain dietary Al concentrations of 120, 500, 1500 ppm at the onset of medullary bone formation and was continued for a period of three weeks after the onset of laying. Two basal diets containing differing concentrations of Ca and P were used. None of the diets was acutely toxic but the addition of Al significantly influenced eggshell thickness. Increasing dietary Ca and P was found to mitigate this effect.

9 citations

Journal Article
TL;DR: Wolff et al. as mentioned in this paper define environmental ethics more broadly and teach utilitarian ethics in a non-pejorative fashion so that graduates of environmental studies and policy programs understand the merits of utilitarian arguments and can comfortably participate in the policymaking arena.
Abstract: Email: wolff017@tc.umn.edu Abstract: Environmental ethicists have focused much attention on the limits of utilitarianism and have generally defined “environmental ethics” in a manner that treats utilitarian environmental ethics as an oxymoron. This is unfortunate because utilitarian ethics can support strong environmental policies, and environmental ethicists have not yet produced a contemporary environmental ethic with such broad appeal. I believe educators should define environmental ethics more broadly and teach utilitarian ethics in a non-pejorative fashion so that graduates of environmental studies and policy programs understand the merits of utilitarian arguments and can comfortably participate in the policymaking arena, where utilitarian ethics continue to play a dominant role.

6 citations


Cited by
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Journal ArticleDOI
22 Jul 2005-Science
TL;DR: Global croplands, pastures, plantations, and urban areas have expanded in recent decades, accompanied by large increases in energy, water, and fertilizer consumption, along with considerable losses of biodiversity.
Abstract: Land use has generally been considered a local environmental issue, but it is becoming a force of global importance. Worldwide changes to forests, farmlands, waterways, and air are being driven by the need to provide food, fiber, water, and shelter to more than six billion people. Global croplands, pastures, plantations, and urban areas have expanded in recent decades, accompanied by large increases in energy, water, and fertilizer consumption, along with considerable losses of biodiversity. Such changes in land use have enabled humans to appropriate an increasing share of the planet’s resources, but they also potentially undermine the capacity of ecosystems to sustain food production, maintain freshwater and forest resources, regulate climate and air quality, and ameliorate infectious diseases. We face the challenge of managing trade-offs between immediate human needs and maintaining the capacity of the biosphere to provide goods and services in the long term.

10,117 citations

Journal ArticleDOI
12 Feb 2010-Science
TL;DR: A multifaceted and linked global strategy is needed to ensure sustainable and equitable food security, different components of which are explored here.
Abstract: Continuing population and consumption growth will mean that the global demand for food will increase for at least another 40 years. Growing competition for land, water, and energy, in addition to the overexploitation of fisheries, will affect our ability to produce food, as will the urgent requirement to reduce the impact of the food system on the environment. The effects of climate change are a further threat. But the world can produce more food and can ensure that it is used more efficiently and equitably. A multifaceted and linked global strategy is needed to ensure sustainable and equitable food security, different components of which are explored here.

9,125 citations

Journal ArticleDOI
08 Aug 2002-Nature
TL;DR: A doubling in global food demand projected for the next 50 years poses huge challenges for the sustainability both of food production and of terrestrial and aquatic ecosystems and the services they provide to society.
Abstract: A doubling in global food demand projected for the next 50 years poses huge challenges for the sustainability both of food production and of terrestrial and aquatic ecosystems and the services they provide to society. Agriculturalists are the principal managers of global useable lands and will shape, perhaps irreversibly, the surface of the Earth in the coming decades. New incentives and policies for ensuring the sustainability of agriculture and ecosystem services will be crucial if we are to meet the demands of improving yields without compromising environmental integrity or public health.

6,569 citations

Journal ArticleDOI
11 Oct 2001-Nature
TL;DR: Recent studies show that a loss of resilience usually paves the way for a switch to an alternative state, which suggests that strategies for sustainable management of such ecosystems should focus on maintaining resilience.
Abstract: All ecosystems are exposed to gradual changes in climate, nutrient loading, habitat fragmentation or biotic exploitation. Nature is usually assumed to respond to gradual change in a smooth way. However, studies on lakes, coral reefs, oceans, forests and arid lands have shown that smooth change can be interrupted by sudden drastic switches to a contrasting state. Although diverse events can trigger such shifts, recent studies show that a loss of resilience usually paves the way for a switch to an alternative state. This suggests that strategies for sustainable management of such ecosystems should focus on maintaining resilience.

6,213 citations

Journal ArticleDOI
20 Oct 2011-Nature
TL;DR: It is shown that tremendous progress could be made by halting agricultural expansion, closing ‘yield gaps’ on underperforming lands, increasing cropping efficiency, shifting diets and reducing waste, which could double food production while greatly reducing the environmental impacts of agriculture.
Abstract: Increasing population and consumption are placing unprecedented demands on agriculture and natural resources. Today, approximately a billion people are chronically malnourished while our agricultural systems are concurrently degrading land, water, biodiversity and climate on a global scale. To meet the world's future food security and sustainability needs, food production must grow substantially while, at the same time, agriculture's environmental footprint must shrink dramatically. Here we analyse solutions to this dilemma, showing that tremendous progress could be made by halting agricultural expansion, closing 'yield gaps' on underperforming lands, increasing cropping efficiency, shifting diets and reducing waste. Together, these strategies could double food production while greatly reducing the environmental impacts of agriculture.

5,954 citations