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RS/CS Suggestions

RS/CS Suggestions (21)

Wednesday, 14 November 2012 09:19

Everglades

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Everglades

Brief description

Nutrient and flow management. Management potentially stuck in a rigidity trap - no new ideas are able to take hold, due to vested capital and power dynamics.

Key References

  1. Potential contact: Lance Gunderson
Wednesday, 14 November 2012 09:17

Glen Canyon Dam

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Glen Canyon Dam

Brief description

Grand Canyon/Colorado River - Dam caused a large regime shift in ecology, but over time management has been adapted to try to approximate the original regime through water releases etc. Learnign how to do this has been achieved through experimentation & adaptive management.

Key References

  1. Mentioned by Lance Gunderson
Tuesday, 06 November 2012 18:46

Aquaculture-related regime shifts

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Aquaculture-related regime shifts

Brief description

Aquaculture growth has led to worries about overfishing and reduction in wild-caught food fish supply because of increased demand for fish meal. As such, the price ratio between fish meal and soybean meal has received much attention as an indicator of changing market conditions. In recent years, the price ratio between these two commodities has become more volatile. Several authors have suggested that the traditional relationship between fish meal and soybean meal has broken down and that this is evidence of increased demand pressure on fish meal. In this article, we investigate the hypothesis that there are two regimes for the relative price between fish meal and soybean meal. The empirical results support this hypothesis, with the low-price regime representing the traditional stable relative price. The continued linkages between the fish meal and the soybean meal markets indicate that aquaculture is reducing its dependency on marine proteins in favour of vegetable proteins.

Key References

  1. Asche, F., Oglend, A. and Tveteras, S. (2012), Regime Shifts in the Fish Meal/Soybean Meal Price Ratio. Journal of Agricultural Economics. doi: 10.1111/j.1477-9552.2012.00357.x
Thursday, 18 October 2012 10:13

Seabird populations

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Seabird populations

Brief description

What they found was a remarkable global consistency between access to fish and seabird breeding success. Wherever they occurred in the world the effect of low fish was similar. Österblom and his colleagues found that breeding reaches a plateau and does not change even as food abundance increases. When the amount of fish in the sea was greater than one-third of maximum levels of fish, the number of chicks produced remained pretty much unaffected. But if the fish abundance fell below this one-threshold, the number of chicks produced declined. "The global pattern shows a threshold below which the numerical breeding response declines strongly as food abundance decreases," says Henrik Österblom. Österblom and his colleagues also found that breeding reaches a plateau and does not change even as food abundance increases.

Key References

  1. Philippe M. Cury, Ian L. Boyd, Sylvain Bonhommeau, Tycho Anker-Nilssen, Robert J.M. Crawford, Robert W. Furness, James A. Mills, Eugene J. Murphy, Henrik u00d6sterblom, Michelle Paleczny, John F. Piatt, Jean-Paul Roux, Lynne Shannon and William J. Sydeman. 2011. Global seabird response to forage fish depletion u2014 one-third for the birds. Science 334, Issue 6063.
  2. http://www.stockholmresilience.org/research/researchnews/saveathirdforthebirds.5.3f0adc2c1344ec370d380001569.html
Thursday, 18 October 2012 10:05

Shrimp farming in Thailand

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Shrimp farming in Thailand

Brief description

We explain how a shift from culture of the black tiger shrimp (Penaeus monodon) to the Pacific white shrimp (Litopenaeus vannamei) took place during 2002-6 in Thailand. We use system innovation theory to help explain how niche substitution led to a regime change within a Thai aquaculture industry trying to maintain international competitiveness but under pressures from a global landscape in which consumers are increasingly concerned with health and ecological sustainability. Support from a vertically integrated major firm, an extensive foundation of learning networks within the industry, and early profitability made the scaling-up and embedding of the experiment with white shrimp very rapid once the formal ban on import of exotic broodstock was lifted. Disease management with domesticated, specific pathogen-free strains of white shrimp has proven much easier than with black shrimp still dependent on capture of wild broodstock. Moreover relative production costs are lower. The switch in species had significant consequences for the environment and firms. Using life cycle analysis we found that rearing white shrimp requires less resource and produces less waste than black shrimp. The shift in regime, however, also made it more difficult for small farms and hatchery businesses.  

Key References

  1. Louis Lebel, Rattanawan Mungkung, Shabbir H. Gheewala, Phimphakan Lebel, Innovation cycles, niches and sustainability in the shrimp aquaculture industry in Thailand, Environmental Science & Policy, Volume 13, Issue 4, June 2010, Pages 291-302, ISSN 1462-9011, 10.1016/j.envsci.2010.03.005. (http://www.sciencedirect.com/science/article/pii/S1462901110000237)
Thursday, 18 October 2012 09:59

Disease virulence

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Disease virulence

Brief description

Environmental transmission can select for increased virulence when direct transmission is low. Increasing the efficiency of direct transmission gives rise to an evolutionary bi-stability, with coexistence of different levels of virulence. The overlooked contribution of environmental transmission may explain the curious appearance of high virulence in pathogens that are typically only moderately pathogenic, as observed for avian influenza viruses and cholera.

Key References

  1. Roche, Benjamin, John M. Drake, Pejman Rohani. 2011. The curse of the Pharaoh revisited: evolutionary bi-stability in environmentally transmitted pathogens. Ecology Letters DOI: 10.1111/j.1461-0248.2011.01619.x
Thursday, 18 October 2012 09:52

Fragmentation & biodiversity loss

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Fragmentation & biodiversity loss

Brief description

Regime shifts in biodiversity associated with landscape fragmentation.

Key References

  1. Pardini R, Bueno Ade A, Gardner TA, Prado PI, Metzger JP. 2010. Beyond the fragmentation threshold hypothesis: regime shifts in biodiversity across fragmented landscapes. PLoS One 5(10):e13666.
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