A semi-empirical dynamic soil acidification model for use in spatially explicit integrated assessment models for Europe

A semi-empirical soil acidification model was developed for use in integrated assessment models on a European scale. The model simulates the time development of base saturation and aluminium concentration using an empirical relationship with pH. An accompanying data set was developed by overlaying European maps of soils, land use, climate and altitude followed by a procedure that aggragates the input data over soil-texture combinations in each EMEP 150 km x 150 km grid cell. Model tests show that themodel gives results comparable to the SMART model, although it overestimates initial base saturation in some areas with high acid input and simulates a faster recovery from acidification than SMART

Market Sampling of Landings of Commercial Fish Species in the Netherlands in 2002

This report contains information on the biological sampling for the market sampling program: which species are sampled, how they were caught, when and where the samples are taken (date and position), how many fish have been measured, how many fish have been aged, etc. The report gives an overview of all the biological sampling activities in 2002 by RIVO on the landings of the commercial important species of herring, mackerel, horse mackerel, blue whiting, greater argentine, sole, plaice, turbot, brill, dab, lemon sole, cod, whiting, Norway lobster and four different species of rays from all ICES areas. This biological sampling took place on landings by both the Dutch fleet as well as foreign fleets landing in the Netherlands. In addition this report contains information on the biological samples collected during research vessel surveys and discard trips both on commercial and non-commercial species

Efficient resource management in dairy farming on sandy soil

Sandy soils in the Netherlands are mainly used for dairy farming. As a result of intensification of dairy farming in the recent past, valued functions of sandy regions now are threatened by high emissions of nitrogen (N) and phosphorus (P) and by increased water consumption by forage crops. Improved utilization efficiency of resources is proposed as a strategy to realise environmental targets in an economically viable way. Experimental results of the prototype system 'De Marke' indicate that an average intensive commercial farm can halve inputs of fertilizers and feeds at least, without the need to reduce milk yield/ha or to export slurry. Water consumption can be reduced by 13%, increasing groundwater 'production' by 570 msuperscript 3/ha. Nitrate concentration in the upper groundwater decreased from 200 to 50 mg/litre. Changes in soil fertility did not lead to serious agricultural problems but costs of milk production increased by 5%. However, additional costs may be compensated for if the extra groundwater is 'harvested' by water companies, because of high cost of purification of surface water and consumer preference for drinking groundwater instead of river-water. In 1999, the examined strategy of improved resource management was implemented on 12 commercial farms, representing the full range of conditions for dairy farming in the Netherlands