Publications

NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.

2000

Abstract

The main purpose of the risk assessment is to assess the future risk from cadmium in mineral P-fertilisers to human health, soils and waters using model calculations. The risk assessment of Cd in mineral fertilisers has been performed according to procedures suggested by ERM (2000). The procedure consists of three modules: 1) The accumulation module; 2) The exposure module; 3) The risk characterisation module. Two scenarios for Cd in mineral P-fertilisers were used: 2.3 mg Cd kg-1 P2O5-(present level of Cd ) and 60 mg Cd kg-1 P2O5 average EU-level).In the accumulation module the future (in 100 years) concentration of Cd in soils was calculated using a mass balance model. Application of P-fertiliser containing 60 mg Cd kg-1 P2O5 increases the soil concentration of Cd by 16 to nearly 100 percent depending on type of crop and region. In the exposure module, the uptake of Cd from the soil to wheat, potato and carrot is calculated as well as the relative contribution from fertilisers to the human uptake of Cd. The application of P-fertilisers containing 60 mg Cd kg-1 P2O5 in 100 years increase the daily intake of Cd by 7

Abstract

Aluminium (Al) has been considered to be a central element for risk evaluation of forest damage due to acidification. It has been hypothesised that Al reduces root growth, nutrient uptake and forest vitality. However, forest monitoring studies fail to show correlations between soil acidification and forest health. In general, no direct relation between Al concentration and forest health has been established. Here, Al concentrations in soil solution were manipulated by weekly additions of dilute AlCl3 to levels that are believed to be unfavorable for plant growth. Four treatments (in triplicate) including a reference and three Al addition levels were established. Effects of enhanced Al concentrations on fine root growth, nutrient uptake and crown condition in a mature Norway spruce forest in Norway were tested (1996-1999). After three years of manipulation, crown condition, tree growth and fine root growth were not affected by potentially toxic Al concentrations. However, the Mg content in current year\"s needles decreased at the highest Al addition treatment. The Mg/Al ratio of fine roots of the same treatment had declined too, which suggests that Al blocked Mg uptake at the root surface. The manipulation will be continued for two more years.