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  • Unknown author (2005-04-22
  • McMahon, Peg (2006-04-25
      In many parts of the world, waste water and run-off from greenhouse roofs is captured in ponds and held or recycled. In low-lying areas, the ponds have to be above ground level.
  • McMahon, Peg (2006-04-25
      Water collection ponds collect waste and run-off water from greenhouses. The water is held or recycled.
  • Wilson, Sandra (2005-04-21
      Orchids are finished off at 80F daytime and 60F nighttime temperatures. Blackout curtains are used to shorten the daylength.
  • Koliba, C. J.; Mills, R. M.; Zia, A. (Public Administration Review, 2011
      What is the most effective framework for analyzing complex accountability challenges within governing networks? Recognizing the multiscale and intersector (public, private, and nonprofit) characteristics of these networks, an accountability model is advanced organized around democratic (elected representatives, citizens, and the legal system), market (owners and consumers), as well as administrative (bureaucratic, professional and collaborative) relationships. This concept draws from 2005 events following Hurricane Katrina. Multiple failures of governing networks to plan for and respond to Katrina include a breakdown in democratic, market, and administrative accountability as well as a pervasive confusion over trade-offs between accountability types emerging from crises. This essay offers several useful recommendations for emergency management planners as well as for those who teach and research.
  • Zia, A.; Koliba, C. (Journal of Comparative Policy Analysis, 2011
      How can accountability be institutionalized across complex governance networks that are dealing with the transboundary pollution problem of mitigating greenhouse gas emissions at multiple spatial, temporal and social scales? To address this question, we propose an accountability framework that enables comparison of the democratic, market and administrative anchorage of actor accountability within and across governance networks. A comparative analysis of performance measures in a sample of climate governance networks is undertaken. This comparative analysis identifies four critical performance management dilemmas in the areas of strategy, uncertain science, integration of multiple scales, and monitoring and verification of performance measures.
  • Marland, G.; Buchholz, T.; Kowalcyzk, T. (Journal of Industrial Ecology, 2013
  • Hirsch, P. D.; Adams, W. M.; Brosius, J. P.; Zia, A.; Bariola, N.; Dammert, J. L. (Conservation Biology, 2011
      There is a growing recognition that conservation often entails trade-offs. A focus on trade-offs can open the way to more complete consideration of the variety of positive and negative effects associated with conservation initiatives. In analyzing and working through conservation trade-offs, however, it is important to embrace the complexities inherent in the social context of conservation. In particular, it is important to recognize that the consequences of conservation activities are experienced, perceived, and understood differently from different perspectives, and that these perspectives are embedded in social systems and preexisting power relations. We illustrate the role of trade-offs in conservation and the complexities involved in understanding them with recent debates surrounding REDD (Reducing Emissions from Deforestation and Degradation), a global conservation policy designed to create incentives to reduce tropical deforestation. Often portrayed in terms of the multiple benefits it may provide: poverty alleviation, biodiversity conservation, and climate-change mitigation; REDD may involve substantial trade-offs. The gains of REDD may be associated with a reduction in incentives for industrialized countries to decrease carbon emissions; relocation of deforestation to places unaffected by REDD; increased inequality in places where people who make their livelihood from forests have insecure land tenure; loss of biological and cultural diversity that does not directly align with REDD measurement schemes; and erosion of community-based means of protecting forests. We believe it is important to acknowledge the potential trade-offs involved in conservation initiatives such as REDD and to examine these trade-offs in an open and integrative way that includes a variety of tools, methods, and points of view.
  • Bell, Michael M.; Lloyd, Sarah E.; Vatovec, Christine (Sociologia Ruralis, 2010
      Against the current moment of rural doubt, we argue that the material, symbolic and relational practices of the rural continue to be articulate aspects of our politics. We term the material practices 'rural power' and the symbolic practices 'the power of the rural'. The relational practices we term 'rural constituencies' when relations are bounded materially and 'constituencies of the rural' when they are bounded symbolically. We apply this framework to a critique of contemporary theory, especially mobilities research, which, we argue, typically speaks with a passive rural voice. We argue for recognising the active rural voice in the mobilisation and stabilisation of the rural.
  • Armitage, D. R.; Plummer, R.; Berkes, F.; Arthur, R. I.; Charles, A. T.; Davidson-Hunt, I. J.; Diduck, A. P.; Doubleday, N. C.; Johnson, D. S.; Marschke, M.; McConney, P.; Pinkerton, E. W.; Wollenberg, E. K. (Frontiers in Ecology and the Environment, 2009
      Building trust through collaboration, institutional development, and social learning enhances efforts to foster ecosystem management and resolve multi-scale society-environment dilemmas. One emerging approach aimed at addressing these dilemmas is adaptive co-management. This method draws explicit attention to the learning ( experiential and experimental) and collaboration ( vertical and horizontal) functions necessary to improve our understanding of, and ability to respond to, complex social-ecological systems. Here, we identify and outline the core features of adaptive co-management, which include innovative institutional arrangements and incentives across spatiotemporal scales and levels, learning through complexity and change, monitoring and assessment of interventions, the role of power, and opportunities to link science with policy.
  • Kollat, J. B.; Reed, P. M.; Rizzo, D. M. (Geophysical Research Letters, 2008
      This work contributes a combination of laboratory-based aquifer tracer experimentation and bias-aware Ensemble Kalman Filtering (EnKF) to demonstrate that systematic modeling errors ( or bias) in source loading dynamics and the spatial distribution of hydraulic conductivity pose severe challenges for groundwater transport forecasting under uncertainty. The impacts of model bias were evaluated using an ammonium chloride tracer experiment conducted in a three dimensional laboratory tank aquifer with 105 near real-time sampling locations. This study contributes a bias-aware EnKF framework that (i) dramatically enhances the accuracy of concentration breakthrough forecasts in the presence of systematic, spatio-temporally correlated modeling errors, (ii) clarifies in space and time where transport gradients are maximally impacted by model bias, and (iii) expands the size and scope of flow- and-transport problems that can be considered in the future.
  • Besaw, L. E.; Rizzo, D. M.; Bierman, P. R.; Hackett, W. R. (Journal of Hydrology, 2010
      In this work, we develop and test two artificial neural networks (ANNs) to forecast streamflow in ungauged basins. The model inputs include time-lagged records of precipitation and temperature. In addition, recurrent feedback loops allow the ANN streamflow estimates to be used as model inputs. Publically available climate and US Geological Survey streamflow records from sub-basins in Northern Vermont are used to train and test the methods. Time-series analysis of the climate-flow data provides a transferable and systematic methodology to determine the appropriate number of time-lagged input data. To predict streamflow in an ungauged basin, the recurrent ANNs are trained on climate-flow data from one basin and used to forecast streamflow in a nearby basin with different (more representative) climate inputs. One of the key results of this work, and the reason why time-lagged predictions of steamflow improve forecasts, is these recurrent flow predictions are being driven by time-lagged locally-measured climate data. The successful demonstration of these flow prediction methods with publicly available USGS flow and NCDC climate datasets shows that the ANNs, trained on a climate-discharge record from one basin, prove capable of predicting streamflow in a nearby basin as accurately as in the basin on which they were trained. This suggests that the proposed methods are widely applicable, at least in the humid, temperate climate zones shown in this work. A scaling ratio, based on a relationship between bankfull discharge and basin drainage area, accounts for the change in drainage area from one basin to another. Hourly streamflow predictions were superior to those using daily data for the small streams tested due the loss of critical lag times through upscaling. The ANNs selected in this work always converge, avoid stochastic training algorithms, and are applicable in small ungauged basins. (C) 2010 Elsevier B.V. All rights reserved.
  • Olander, Lydia; Wollenberg, Eva; Tubiello, Francesco; Herold, Martin (Environmental Research Letters, 2013
  • Bomblies, A. (Parasites & VectorsParasites Vectors, 2014
      Background: The modeling of malaria vector mosquito populations yields great insight into drivers of malaria transmission at the village scale. Simulation of individual mosquitoes as "agents" in a distributed, dynamic model domain may be greatly beneficial for simulation of spatial relationships of vectors and hosts. Methods: In this study, an agent-based model is used to simulate the life cycle and movement of individual malaria vector mosquitoes in a Niger Sahel village, with individual simulated mosquitoes interacting with their physical environment as well as humans. Various processes that are known to be epidemiologically important, such as the dependence of parity on flight distance between developmental habitat and blood meal hosts and therefore spatial relationships of pools and houses, are readily simulated using this modeling paradigm. Impacts of perturbations can be evaluated on the basis of vectorial capacity, because the interactions between individuals that make up the population-scale metric vectorial capacity can be easily tracked for simulated mosquitoes and human blood meal hosts, without the need to estimate vectorial capacity parameters. Results: As expected, model results show pronounced impacts of pool source reduction from larvicide application and draining, but with varying degrees of impact depending on the spatial relationship between pools and human habitation. Results highlight the importance of spatially-explicit simulation that can model individuals such as in an agent-based model. Conclusions: The impacts of perturbations on village scale malaria transmission depend on spatial locations of individual mosquitoes, as well as the tracking of relevant life cycle events and characteristics of individual mosquitoes. This study demonstrates advantages of using an agent-based approach for village-scale mosquito simulation to address questions in which spatial relationships are known to be important.
  • Eppstein, M. J.; Grover, D. K.; Marshall, J. S.; Rizzo, D. M. (Energy Policy, 2011
      A spatially explicit agent-based vehicle consumer choice model is developed to explore sensitivities and nonlinear interactions between various potential influences on plug-in hybrid vehicle (PHEV) market penetration. The model accounts for spatial and social effects (including threshold effects, homophily, and conformity) and media influences. Preliminary simulations demonstrate how such a model could be used to identify nonlinear interactions among potential leverage points, inform policies affecting PHEV market penetration, and help identify future data collection necessary to more accurately model the system. We examine sensitivity of the model to gasoline prices, to accuracy in estimation of fuel costs, to agent willingness to adopt the PHEV technology, to PHEV purchase price and rebates, to PHEV battery range, and to heuristic values related to gasoline usage. Our simulations indicate that PHEV market penetration could be enhanced significantly by providing consumers with ready estimates of expected lifetime fuel costs associated with different vehicles (e.g., on vehicle stickers), and that increases in gasoline prices could nonlinearly magnify the impact on fleet efficiency. We also infer that a potential synergy from a gasoline tax with proceeds is used to fund research into longer-range lower-cost PHEV batteries. (C) 2011 Elsevier Ltd. All rights reserved.
  • Vermeulen, Sonja Joy; Aggarwal, PK; Ainslie, A; Angelone, C; Campbell, Bruce Morgan; Challinor, AJ; Hansen, J; Ingram, JSI; Jarvis, A; Kristjanson, P (2010
  • Mendez, V. E.; Bacon, C. M.; Olson, M. B.; Morris, K. S.; Shattuck, A. (2010
      We used households as the primary unit of analysis to synthesize agrobiodiversity research in small-scale coffee farms and cooperatives of Nicaragua and El Salvador. Surveys, focus groups, and plant inventories were used to analyze agrobiodiversity and its contribution to livelihoods. Households managed high levels of agrobiodiversity, including 100 shade tree and epiphyte species, food crops, and medicinals. Small farms contained higher levels of agrobiodiversity than larger, collectively managed cooperatives. Households benefited from agrobiodiversity through consumption and sales. To better support agrobiodiversity conservation, our analysis calls for a hybrid approach integrating bottom-up initiatives with the resources from top-down projects.

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