Designing a Decision Support System for Marine Reserves Management: An Economic Analysis for the Dutch North Sea

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 considers both the economic returns from fisheries and the ecological value of marine biodiversity. A number of suggestions are given on how to extend and improve the DSS.Decision Support System, Marine Biodiversity Conservation, DPSIR Framework, Bioeconomic Modeling, North Sea

The Effect of HIV/AIDS Driven Labor Organization on Agrobiodiversity: an Empirical Study in Ethiopia

Improved micronutrient intake contributes to delaying the progression of HIV into AIDS and to reducing HIV infection rates. Higher agrobiodiversity in the homegarden contributes to improving the nutritional status of farm households. Farm households with HIV/AIDS affected members observe a decrease in labor supply and productivity causing them to reallocate labor. The reallocation of labor may result in change in agrobiodiversity. Sharecropping is often used to alleviate labor shortage in agricultural production. The purpose of this paper is to analyze the implications of HIV/AIDS on agrobiodiversity through sharecropping arrangements. The study is based on a survey among 205 farm households in the Jimma zone of South Western Ethiopia. Results show that HIV/AIDS driven increase in sharecropping has a positive effect on perennial and overall agrobiodiversity in the homegarden. This offers additional intervention options to mitigate the impacts of HIV/AIDS among farm households.agrobiodiversity, Ethiopia, HIV/AIDS, labor organization, sharecropping, Farm Management, Labor and Human Capital,

Economic Incentives for Entry and Exit in Gum Arabic Agroforestry System in Sudan

The gum tree (Acacia senegal) in the Sahel-Sudan zone has many environmental benign functions. An important function is to control desertification. In this paper we analyze farmers' economic incentives to preserve the existing gum trees and their incentives to create new plantations using a real options approach. Results indicate that agricultural crops provide higher economic benefits as compared to gum agroforestry system. However, on the one hand, as gum arabic is produced during the dry period and land is abundant, there are low incentives for deforestation. Instead, farmers' tend to leave the land idle and let the tree growing. On the other hand, our results suggest that an increase in the prices of gum arabic of about 330 per cent is needed to induce entry and a shift in land use system from continuous agricultural production to gum agroforestry system.gum arabic, deforestation, entry and exit, real options, Sudan, Crop Production/Industries, D4, N5, O13, Q12, Q23,

Biological control of invasive plant species: stochastic economic analysis

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.Stochastic, Optimisation, Biological control, Californian thistle, Economics.,

DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality.Resource /Energy Economics and Policy,

Measuring the Economic Value of Two Habitat Defragmentation Policy Scenarios for the Veluwe, The Netherlands

This paper offers an economic value assessment of a nature protection programme in the Veluwe. This programme involves two defragmentation scenarios: the first scenario connects the central part of the Veluwe with the IJssel river forelands in a north-eastern direction, while the second scenario is focused on defragmentation in a south-western direction, where the Rhine river forelands are located. The valuation is based on a questionnaire that was administered during face-to-face interviews in the Veluwe area and through the Internet. We employ a contingent valuation approach to assess the respondents’ willingness to pay for the realisation of the defragmentation scenarios. It appears that the mean willingness to pay for the two defragmentation scenarios are € 59.7 and € 162.2 per respondent. These two willingness-to-pay estimates, which refer to a lump sum payment (or ‘once-and-for-all payment’), are based on a lognormal and Weibull distribution respectively. In addition to the willingness to pay, we also estimate recreation benefits of the Veluwe. To that end, we use the travel cost technique, the purpose of which is to arrive at an estimate of the site’s consumer surplus. According to this technique, the yearly recreational benefits are estimated between € 0.06 and € 0.45 per visitor. Whereas the former estimate is based on the fuel costs only, the latter covers also insurance and maintenance costs, and capital depreciation. Finally, we performed an aggregation of individual WTP estimates over Dutch households. With the resulting aggregate estimates we are able to compare the total costs and benefits of the two scenarios for habitat fragmentation in the Veluwe. The result of such a simple comparison turns out to critically depend on whether the mean or median estimate is used for aggregation. If aggregation of individual WTP estimates is based on mean values, then the benefits far exceed the estimated costs of defragmentation. In other words, based on an integrated economic-ecological analysis it makes sense to execute the defragmentation measures described in the scenarios. However, aggregate estimates obtained by using median values result in higher costs than aggregate estimates that are based on mean values. Even stronger, median-based estimates show that the costs of implementing scenario 2 are higher than the total benefits of this scenario.Economic value, Nature protection, Defragmentation policy, Veluwe

Flexible strategies for coping with rainfall variability: seasonal adjustments in cropped area in the Ganges basin

This work was partly carried out by the Himalayan Adaptation, Water and Resilience (HIAWARE) consortium under the Collaborative Adaptation Research Initiative in Africa and Asia (CARIAA). Under this initiative, CS and HB received financial support from the UK Government’sDepartment for International Development and the International Development Research Centre, Ottawa, Canada. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.One of the main manifestations of climate change will be increased rainfall variability. How to deal with this in agriculture will be a major societal challenge. In this paper we explore flexibility in land use, through deliberate seasonal adjustments in cropped area, as a specific strategy for coping with rainfall variability. Such adjustments are not incorporated in hydro-meteorological crop models commonly used for food security analyses. Our paper contributes to the literature by making a comprehensive model assessment of inter-annual variability in crop production, including both variations in crop yield and cropped area. The Ganges basin is used as a case study. First, we assessed the contribution of cropped area variability to overall variability in rice and wheat production by applying hierarchical partitioning on time-series of agricultural statistics. We then introduced cropped area as an endogenous decision variable in a hydro-economic optimization model (WaterWise), coupled to a hydrology-vegetation model (LPJmL), and analyzed to what extent its performance in the estimation of inter-annual variability in crop production improved. From the statistics, we found that in the period 1999–2009 seasonal adjustment in cropped area can explain almost 50% of variability in wheat production and 40% of variability in rice production in the Indian part of the Ganges basin. Our improved model was well capable of mimicking existing variability at different spatial aggregation levels, especially for wheat. The value of flexibility, i.e. the foregone costs of choosing not to crop in years when water is scarce, was quantified at 4% of gross margin of wheat in the Indian part of the Ganges basin and as high as 34% of gross margin of wheat in the drought-prone state of Rajasthan. We argue that flexibility in land use is an important coping strategy to rainfall variability in water stressed regions