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Registros recuperados: 8
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Biological control of invasive plant species: stochastic economic analysis AgEcon
Chalak-Haghighi, Morteza; Ruijs, Arjan; van Ierland, Ekko C..
We analysed to what extent the stochastic effects of two biological control agents (i.e. weevils and mycoherbicides) affect the optimal choice of Californian thistle control. A stochastic, dynamic optimisation model was set up to analyse strategies that maximise the expected net present values. We analysed the cost-effective strategies to control the thistle for deterministic and stochastic cases. Results show that the stochasticity of the efficacy of weevils does not affect the optimal strategy. Compared to the deterministic case, however, mycoherbicides will be introduced at a higher level of weed density if we take the stochastic effect of mycoherbicides into account.
Tipo: Conference Paper or Presentation Palavras-chave: Stochastic; Optimisation; Biological control; Californian thistle; Economics..
Ano: 2009 URL: http://purl.umn.edu/48153
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Climate Change and the Stability of Water Allocation Agreements AgEcon
Ansink, Erik; Ruijs, Arjan.
We analyse agreements on river water allocation between riparian countries. Besides being efficient, water allocation agreements need to be stable in order to be effective in increasing the efficiency of water use. In this paper, we assess the stability of water allocation agreements, using a game theoretic model. We consider the effects of climate change and the choice of a sharing rule on stability. Our results show that both a decrease in mean river flow and an increase in the variance of river flow decrease the stability of an agreement. An agreement where the downstream country is allocated a fixed amount of water has the lowest stability compared to other sharing rules.
Tipo: Working or Discussion Paper Palavras-chave: Resource /Energy Economics and Policy.
Ano: 2007 URL: http://purl.umn.edu/10272
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Designing a Decision Support System for Marine Reserves Management: An Economic Analysis for the Dutch North Sea AgEcon
van Ierland, Ekko C.; Ding, Hongyu; Ruijs, Arjan.
In this paper we discuss how a Decision Support System (DSS) for managing the marine environment can be set up. We use the Driving force-Pressure-State-Impact-Respond (DPSIR) framework to analyze which are the major driving forces impacting upon the marine environment in the North Sea. Moreover, a number of potential responses are identified. Furthermore, a preliminary and simplified optimization model has been set up and can be used in a DSS to decide on the best location of marine reserves for the protection of species. The model is based on a bio-economic metapopulation model that can be used to decide which parts of the sea should be opened for fisheries and which should be protected as marine reserve. It accounts for the dispersal of fish and...
Tipo: Working or Discussion Paper Palavras-chave: Resource /Energy Economics and Policy.
Ano: 2007 URL: http://purl.umn.edu/10266
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Economics of controlling invasive species: optimal control and stability of ecological-economic system AgEcon
Chalak, Morteza; Ruijs, Arjan; Hemerik, Lia; van der Werf, Wopke; van Ierland, Ekko C..
Natural enemies such as herbivores that are introduced to reduce invasive plants can spill over into nature, threaten indigenous species and impose significant costs. We develop a bioeconomic model to analyse the optimal control management strategy of an introduced herbivore that has spilled over from a managed system to a natural area. Cost-effective control strategies are analysed that reduce the spillover effects of herbivores on endangered plants species to reduce the risk of extinction and increase benefits obtained from the ecosystem. We consider two competing indigenous plant species as the representatives of the plant community. Only one of these species is consumed by introduced herbivore. We show that the optimal level of controlling herbivores...
Tipo: Presentation Palavras-chave: Economics; Biological agent; Externality; Spillover; Control; Environmental Economics and Policy.
Ano: 2012 URL: http://purl.umn.edu/124374
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Effects of Great Barrier Reef Degradation on Recreational Demand: A Contingent Behaviour Approach AgEcon
Kragt, Marit Ellen; Roebeling, Peter C.; Ruijs, Arjan.
Agricultural run-off from the Great Barrier Reef catchment area may cause degradation of coral reefs, affecting the tourism sector that relies on healthy reefs for its income generation. A Contingent Behaviour approach is used to determine the effect of reef degradation on demand for recreational dive and snorkel trips, for a case study of the Great Barrier Reef (GBR) in Australia. We assessed how reef degradation affects GBR tourism and to what extent reef-trip demand depends on the visitors' socio-economic characteristics. A count data model is developed, and results indicate that an average visitor would undertake about 60% less trips to the GBR per year, given a combined 80%, 30% and 70% decrease in coral cover, coral diversity and fish diversity,...
Tipo: Conference Paper or Presentation Palavras-chave: Coral reef; Recreation; Contingent Behaviour model; Count data models; Resource /Energy Economics and Policy; Q26; Q51; Q57.
Ano: 2006 URL: http://purl.umn.edu/25753
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Effects of Great Barrier Reef Degradation on Recreational Demand: A Contingent Behaviour Approach AgEcon
Kragt, Marit Ellen; Roebeling, Peter C.; Ruijs, Arjan.
Degradation of coral reefs may affect the number of tourists visiting the reef and, consequently, the economic sectors that rely on healthy reefs for their income generation. A Contingent Behaviour approach is used to estimate the effect of reef degradation on demand for recreational dive and snorkel trips, for a case study of the Great Barrier Reef (GBR) in Australia. We assessed how reef degradation affects GBR tourism and to what extent reef-trip demand depends on the visitors’ socio-economic characteristics. A count data model is developed, and results indicate that an average visitor would undertake about 60% less reef trips per year given a combined 80%, 30% and 70% decrease in coral cover, coral diversity and fish diversity, respectively. This...
Tipo: Working or Discussion Paper Palavras-chave: Environmental Economics and Policy.
Ano: 2006 URL: http://purl.umn.edu/12228
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THE IMPACT OF TRANSPORT- AND TRANSACTION-COST REDUCTIONS ON FOOD MARKETS IN DEVELOPING COUNTRIES: EVIDENCE FOR TEMPERED EXPECTATIONS FOR BURKINA FASO AgEcon
Ruijs, Arjan; Schweigman, Caspar; Lutz, Clemens.
Reductions in transport and transaction costs are expected to have a major effect on the functioning of food markets in developing countries. For many developing countries, this is a relevant issue as it may have important consequences for the food markets in urban and rural deficit areas. A partial equilibrium model is presented to analyze the effects of reduced costs on cereal price formation, inter-regional cereal trade, and farmers' and traders' storage strategies for the case of Burkina Faso. Our results show that the high expectations with regard to the direct effects of cost reductions on food prices and food availability require some nuance. First, the effects of even a huge reduction of transport costs only will be small. Secondly, an element...
Tipo: Conference Paper or Presentation Palavras-chave: Marketing.
Ano: 2003 URL: http://purl.umn.edu/25866
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Welfare and Distribution Effects of Water Pricing Policies AgEcon
Ruijs, Arjan.
In this paper, distribution and welfare effects of changes in block price systems are evaluated. A method is discussed to determine, for a Marshallian demand function, equivalent variation in case of a block price system. The method is applied to analyze welfare and distribution effects of changing water prices in the Metropolitan Region of São Paulo. Results show that there is a trade off between average welfare and income distribution. A pro-poor price system may result in lower average welfare than a flat price system, but in higher individual welfare for the poor. Moreover, there is a trade off between revenues for the water company and income distribution. Even though pro-poor price systems may not be as good for average welfare as flat price systems,...
Tipo: Working or Discussion Paper Palavras-chave: Water demand; Welfare economics; Equivalent variation; Food Security and Poverty; Resource /Energy Economics and Policy; D63; Q25; Q56.
Ano: 2007 URL: http://purl.umn.edu/7441
Registros recuperados: 8
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