Rolf A. Groeneveld

Nitrate leaching in dairy farming: economic effects of environmental restrictions

Nitrate leaching is an important environmental problem, because it causes pollution of groundwater and surface water. Dairy farming makes an important contribution to nitrate leaching. This study analyses the economic impacts of reductions in nitrate leaching for dairy farms in the Netherlands. Using a non-linear partial optimisation model for the economic and ecological aspects of the problem, the study shows how the financial balances of dairy farms change when nitrate losses are reduced to the maximum admissible nitrate leakage of 34 kg N ha−1 year−1. Model results indicate that the differences in the reduction of financial balance vary between NLG 0 and 549 ha−1 year−1, while in some cases it is extremely difficult, if not impossible, to reach the maximum admissible level. (Note: NLG 1 = US

The role of spatial information in the preservation of the shrimp nursery function of mangroves: A spatially explicit bio-economic model for the assessment of land use trade-offs

0.50 as at 22 July 1998).

Costs and benefits of adapting spatial planning to climate change: lessons learned from a large-scale urban development project in the Netherlands

Conversion to aquaculture affects the provision of important ecosystem services provided by mangrove ecosystems, and this effect depends strongly on the location of the conversion. We introduce in a bio-economic mathematical programming model relevant spatial elements that affect the provision of the nursery habitat service of mangroves: (1) direct or indirect connection of mangroves to watercourses; (2) the spatial allocation of aquaculture ponds; and (3) the presence of non-linear relations between mangrove extent and juvenile recruitment to wild shrimp populations. By tracing out the production possibilities frontier of wild and cultivated shrimp, the model assesses the role of spatial information in the trade-off between aquaculture and the nursery habitat function using spatial elements relevant to our model of a mangrove area in Ca Mau Province, Viet Nam. Results show that where mangrove forests have to coexist with shrimp aquaculture ponds, the inclusion of specific spatial information on ecosystem functions in considerations of land allocation can achieve aquaculture benefits while largely preserving the economic benefits generated by the nursery habitat function. However, if spatial criteria are ignored, ill-advised land allocation decisions can easily lead to a collapse of the mangroves nursery function.

Wildlife as insurance against rainfall fluctuations in a semi-arid savanna setting of southeastern Zimbabwe

Climate change increases the vulnerability of low-lying coastal areas. Careful spatial planning can reduce this vulnerability, provided that decision-makers have insight into the costs and benefits of adaptation options. This paper addresses the question which adaptation options are suitable, from an economic perspective, to adapt spatial planning to climate change at a regional scale. We apply social cost–benefit analysis to assess the net benefits of adaptation options that deal with the impacts of climate change-induced extreme events. From the methods applied and results obtained, we also aim at learning lessons for assessing climate adaptation options. The case study area, the Zuidplaspolder, is a large-scale urban development project in the Netherlands. The costs as well as the primary and secondary benefits of adaptation options relating to spatial planning (e.g. flood-proof housing and adjusted infrastructure) are identified and where possible quantified. Our results show that three adaptation options are not efficient investments, as the investment costs exceed the benefits of avoided damages. When we focus on ‘climate proofing’ the total area of the Zuidplaspolder, when the costs and benefits of all the presented adaptation options are considered together, the total package has a positive net present value. The study shows that it is possible to anticipate climate change impacts and assess the costs and benefits of adjusting spatial planning. We have learned that scenario studies provide a useful tool but that decision-making under climate change uncertainty also requires insight into the probabilities of occurrence of weather extremes in the future.

Global warming and the economics of land-use and land-cover change

This paper presents modeling approaches for wildlife conservation in a semi-arid savanna setting where there are frequent occurrences of drought. The model was used to test the extent to which wildlife income offers opportunities to reduce fluctuations in income as a result of variations in annual rainfall. For the application of the model the wildlife and agro-pastoral systems of southeastern Zimbabwe were simulated. Results show that wildlife income has the potential to compensate for some of the losses in expected income from livestock during droughts. However, wildlife income becomes second best to irrigated agriculture in stabilizing income in areas that show highly fluctuating rainfall. Possible reasons for this include high costs of exploiting the wildlife resource, and the small fraction of wildlife revenues received by households and communities. In order to search for sustainable solutions in areas such as the southeastern low veld of Zimbabwe, it is also important to be aware that the current human population and livestock densities are far above current sustainable levels. Our results therefore suggest that current and future efforts to conserve biodiversity are doomed to fail if there are no efforts made to decongest areas surrounding parks of high densities of human and herbivore populations, and to let local households earn more revenues from wildlife.

Ecological Effectiveness of Agri-Environment Schemes in Different Agricultural Landscapes in The Netherlands

Land-use and land-cover change (LUCC) is driven by a combination of: (1) biophysical factors which determine the capability of land use; (2) technological and economic considerations which determine the socioeconomic feasibility of land use and (3) institutional and political arrangements which determine the acceptability of land use (e.g., Barlowe, 1986; Turner et al., 1995).