• Programmeringsstudie Veranderend Landgebruik ; Gedrag van geaccumuleerde stoffen in verband met veranderingen in landgebruik en herstelbaarheid van ecosystemen

      Meulen-Smidt GRB ter; Vries W de; Bril J; Ma W; Dienst Landbouwkundig Onderzoek (DLO); LBG; AB-DLO, Haren; SC-DLO, Wageningen; IBN-DLO, Arnhem (Rijksinstituut voor Volksgezondheid en Milieu RIVM, 1996-12-31)
      The aim of this Programming Study on 'Behaviour of Accumulated Contaminants in relation to Land Use Changes and Recoverability of Ecosystems' was to determine: 1) the available knowledge and 2) the short-, medium- and long-term research, needed to develop a risk assessment for the effects of mobilisation of nutrients and contaminants due to land-use changes from agriculture to nature or forest conservation. The most relevant changes in soil condition, which can take place after afforestation, are concluded to be acidification and increase in dissolved organic carbon. The development of wetlands can lead to decreases in redoxpotential and acidification. These changes in soil condition can result in mobilisation of phosphate and heavy metals. Risks from organic micropollutants are probably lower ; however, as yet not much is known about this. Increased contaminant mobility can lead to a decrease in decomposition, an increase in internal concentrations of toxicants in soil fauna and secondary poisoning of terrestrial fauna. The study also concludes that risk assessment for land-use changes will require integration of existing models. A 'quick-and-dirty' model integration is recommended as a 1 to 2-year research programme, along with research on existing nature-development projects to be used as model systems for medium-term research programmes. For long-term research priority will be given to monitoring, process research and model integration.