To determine the importance of field boundary habitats for farmland biodiversity, we surveyed a total of 193 boundaries from four climatically and agriculturally dissimilar regions in Finland. We measured the current plant species richness and composition of the boundaries, and, based on the differences in vegetation characteristics, we describe six boundary types.The observed plant species were mainly indicators of fresh to wet soils and moderate to rich mineral nitrogen content. The most frequent species were tall, perennial monocots and dicots indicating the high productivity of the vegetation. Moreover, herbicide-tolerant species were common. No species rare for Finland were found. In animal husbandry regions, the most frequent species were sown grassland species and typical grassland weeds. In cereal production regions, fast-spreading root weeds tolerant of herbicides were the most frequent. Mean species richness was highest in the cluster Calamagrostis-Phalaris (24 species (s) / boundary (b)), which we considered as representative of moist sites with some disturbance by agricultural practices. Most species-poor were the clusters ElymusAnthriscus (14 s/b) and Elymus-Cirsium (16 s/b), both found predominantly in cereal production regions in southern Finland.Our results suggest that the biodiversity value of boundaries is lowest in the most intensive cereal production areas and highest in areas of mixed farming.

The cadmium (Cd) contents of oats (Avena sativa L.) in Finland were examined over a 3 year period in three types of trials: official variety, organic vs conventional cultivation, and nitrogen fertilization trials. Large seasonal and regional variations were found in the Cd concentrations. In official variety trials, the mean Cd contents in 1997, 1998, and 1999 were 0.046, 0.029, and 0.052 mg kg(-1) dry weight (dw), respectively, ranging from 0.008 to 0.120 mg kg(-1) dw. The concentrations were generally well below the maximum permitted level of 0.100 mg kg(-1) fresh weight. No significant differences were found between the organic and the conventional cultivation techniques. Nitrogen (N) fertilization increased the Cd contents of oats especially at high nitrogen rates (160 kg N hectare(-1) (ha)). Significant cultivar differences (p < 0.001) were determined in all trials. Cultivars Salo and Kolbu had consistently higher contents, and Belinda and Roope had lower Cd contents among the different growing conditions. Hence, it is possible to cultivate and develop oat cultivars less likely to accumulate Cd.

No abstract

The effects of soil forming (SF) and plant density (PD) on the carrot yield, mean root weight and internal quality was studied in field experiments in 1993 and 1994. 'Fontana BZ' carrots were grown in flat land, a narrow ridge, a broad ridge, and a compacted broad ridge soil configurations with low (LD) and high (HD) target plant densities, four and seven hundred thousand carrots per hectar. The total and marketable yields were larger in flat land and narrow ridge than in the broad- and compacted broad ridges in 1993 and in 1994 at HD. The number of marketable carrots were highest with the flat land soil configurations in both years. A dry spring in 1993 favored flat land growing conditions; in ridges the fine sand dried quickly. SF did not influence the mean weight of a marketable carrot in 1993, but in 1994 the narrow ridge configuration resulted in heavier carrots than the flat land or broad ridge growing conditions. In the climatically more unfavorable year of 1993, SF and PD affected quality; dry matter was lower in flat land than in the ridges. At HD, the flat land soil configuration produced higher glucose and fructose than carrots grown in the narrow and broad ridges. Dietary fiber and vitamin C were higher in narrow ridge than in compacted broad ridge grown carrots. At LD the flat land and broad ridge produced highest and compacted broad ridge the lowest beta-carotene contents; alpha-carotene was higher at LD than at HD.

No abstract