帮助小的和不那么小的企业提高他们的三重底线成绩

要维持其市场地位,中小企业就必须提高他们的效率.然而,他们往往因为缺少时间、金钱和信息而难以对他们自己的活动、制定目标以及因此不断提高产品和服务(经济上、社会上和环境上)做出正确估价.现有的复杂的国际环境管理方案,对于中小企业常常不适用.不同级别信息“门童“间的合作,对于提高中小企业的环境与社会健康生产方式意识、教给他们日常业务中一体化关注环境与社会的方法、确立经济地位以及奖励这些努力,都是十分必要的.     

The plankton tower. II. Release of nutrients from sediments due to changes in the density of bottom water

Results of an enclosure experiment carried out in Kiel Bight are presented. A water column of about 30 m³, extending from the surface to the bottom over a 3 m² patch of sediment (coarse sand), was isolated and observed over a period of 33 days. Considerable water exchange took place with the surroundings partly because of near-surface openings that appeared in the enclosure but mainly because of density changes due to salinity fluctuations in the surrounding water. This denser water entered the enclosure through the sediments, displacing the lighter water through the near-surface openings. Very high nutrient and low oxygen values were measured in the bottom water immediately following this higher-density water influx. The same effect was observed outside the enclosure, but this phenomenon was not marked here, probably due to greater turbulent mixing obscuring this effect. It is postulated that interstitial, water is flushed out of coarse-grained sediments by gravity displacement due to changes in the density of bottom water. In certain areas this mechanism of nutrient release from the sediments is presumably of great ecological importance, both for the phytoplankton and the benthos.Publication no. 83 of the Joint Research Program at Kiel University (Sonderforschungsbereich 95 der Deutschen Forschungsgemeinschaft).     

Complex courtship in a bimodal grasshopper hybrid zone

Grasshoppers of the Chorthippus albomarginatus-group, which is outstanding with respect to its complex courtship song, were studied at fifteen localities in the Ukraine and Moldova. The analysis of the courtship songs revealed two species: C. albomarginatus in north-eastern Ukraine and Chorthippus oschei in the south-western Ukraine and Moldova. In a belt about 200 km wide, not only were one or the other pure species found, but also males with intermediate song characters. C. albomarginatus and C. oschei were hybridised in the laboratory, and F1 hybrid males as well as F2 hybrid males produced intermediate song patterns, quite similar to those recorded in the field. We defined a "hybrid song score" for intermediate songs. The score showed a bimodal distribution with most songs resembling one or other parental type, but with only a few intermediates. At several localities, where hybrids with songs similar to one of the parental species dominated, some individual males sang more similarly to the other species. In one locality, two hybrid populations only 3 km apart had different parental types. Hybrid songs can contain novel elements, even more complex than the parental ones, which may offer a new starting point for sexual selection. We suggest that genetic introgression occurs between the two sibling species C. albomarginatus and C. oschei within a wide hybrid zone stretching over a distance of several hundred kilometres, but with a patchy spatial distribution. Electronic Supplementary Material Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material. Communicated by D. Gwynne