Meat and bone meal (MBM) contains appreciable amounts of nitrogen (N), phosphorus and calcium making it interesting as fertilizer to various crops. The effect of Norwegian MBM as N fertilizer has been evaluated in pot and field experiments. The soils used in the pot experiment were peat and a sand/peat mixture, both low in content of plant nutrients. The field experiment was carried out on a silt loam. In the pot experiment increasing amounts of MBM gave significantly increased yields, although there was a partly N immobilisation shortly after seeding the soil based on peat organic matter. In the field experiment there was no period of N immobilisation and good N effect was found also for small amounts of MBM (Total N 50 kg ha -1 ). At total N 100 kg ha -1 there were no significant differences in grain yield of spring wheat between the treatments with MBM, mineral N fertilizer, and combination of MBM and mineral N fertilizer (N 50 kg ha -1 from each). The results indicate that the relative N efficiency of MBM compared to mineral fertilizer is 80% or higher, if MBM is applied to cereals in spring.

Quantifying P losses to surface waters at different scales and partitioning of the loads into P losses from point sources and diffuse sources are significant future challenges for river basin managers. The agricultural share of P losses to surface waters is, in many river basins, increasing and therefore becoming more important to quantify and analyse. The importance of phosphorus losses from agricultural land was analysed using monitoring data and two different models for 35 micro-catchments (<30 km 2 ) in the Nordic-Baltic region of Europe, 17 European macro-catchments (250-11 000 km 2 ) and 10 large European river basins (>50 000 km 2 ). Average annual phosphorus loss from agricultural land in the micro-catchments varied from 0.1 to 4.7 kg P ha )1 and showed no relationship with the short-term P surplus on agricultural land. The average annual total P loss from agricultural land showed equally large variation in the 17 macro-catchments (0.1-6.0 kg P ha )1 ), but the range was less for the 10 larger river basins (0.09-2.0 kg P ha )1 ). The annual P loss from the 35 micro-catchments was greatest in the micro-catchments characterized by soil erosion and a high proportion of surface run-off as in the Norwegian catchments. The same pattern was true for the 17 macro-catchments where the model-simulated total P loss from agricultural land was greatest in the catchments in northern and southern parts of Europe. The main diffuse pathways for total P loads in the 17 macro-catchments were simulated with the MONERIS model. On average, soil erosion and surface run-off was estimated to have contributed 53% (4.1-81%), groundwater 14% (0.2-41.7%) and tile drainage water 3% (0-14.0%).

This paper describes nitrogen losses from, and the characteristics of, 35 selected catchments (12 to 2000 ha) in the Nordic and Baltic countries. Average annual losses of N in 19941997 ranged from 5 to 75 kg ha 1 . Generally, the lowest losses were observed in the Baltic countries and the highest in Norway. The N losses were also characterised by significant within-country and interannual variations, particularly in the Norwegian catchments. An important finding of the study is that the average nutrient losses varied greatly among the catchments studied. The main explanations for this variability were water runoff, fertiliser use (especially the amount of manure), soil type and erosion (including stream bank erosion). However, there were several exceptions, and it was difficult to find general relationships between the individual factors. For example, there was poor correlation between nitrogen losses and surpluses. Therefore, the results suggest that the observed variability in N losses cannot have been due solely to differences in farm management practices, although the studied catchments do include a wide range of nutrient application levels, animal densities and other relevant elements. There is considerable spatial variation in the physical properties (soil, climate, hydrology, and topography) and the agricultural management of the basins, and the interaction between and relative effects of these factors has an important impact on erosion and nutrient losses. In particular, hydrological processes may have a marked effect on N losses measured in the catchment stream water. The results indicate that significant differences in hydrological pathways (e.g. the relationship between fast-and slow-flow processes) lead to major regional differences in N inputs to surface waters and therefore also in the response to changes in field management practices. Agricultural practices such as crop rotation systems, nutrient inputs and soil conservation measures obviously play a significant role in the site-specific effects, although they cannot explain the large regional differences observed in this study. The interactions between agricultural practices and basic catchment characteristics, including hydrological processes, determine the final losses of nitrogen to surface waters, hence it is necessary to understand these interactions to manage diffuse losses of agricultural nutrients efficiently.

A proposal of a differentiated regulatory framework for genetically engineered organisms that can stimulate research and development while maintaining oversight and control.

Large areas in Europe may experience frozen soils during winter periods which pose special challenges to modelling. Extensive data are collected in small agricultural catchments in Nordic and Baltic countries. An analysis on measurements, carried out in four small agricultural catchments has shown that a considerable amount of the yearly nutrient loss occurs during the freezing period. A freezing period was defined as the time period indicated by the maximum and minimum points on the cumulative degree-day curve. On average 6-32% of the yearly runoff was generated during this period while N-loss varied from 5-35% and P loss varied from 3-33%. The results indicate that infiltration into frozen soils might occur during the freezing period and that the runoff generating processes, at least during a considerable part of the freezing period, are rather similar compared to the processes outside the freezing period. Freeze-thaw cycles affect the infiltration capacity and aggregate stability, thereby the erosion and nutrient losses. The Norwegian catchment had a high P loss during the freezing period compared to the other catchments, most likely caused by catchment characteristics such as slope, soil types, tillage methods and fertiliser application. It is proposed to use data, collected on small agricultural dominated catchments, in the calibration and validation of watershed management models and to take into account runoff and nutrient loss processes which are representative for cold climates, thereby obtaining reliable results.