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Kristin Nerlich Frieder Seidl Klaus Mastel Simone Graeff-H?nninger Wilhelm Claupein 《Gesunde Pflanzen》2012,64(3):129-139
The increasing cultivation of energy crops in the last few years may have an impact on changes in the environment, biodiversity and the landscape. Due to a longer rest of soil and reduced application of pesticides, perennial crops such as short rotation coppice (SRC) offer benefits that can have a positive effect on the biodiversity. However, to assess the overall impact of SRC on biodiversity, information on the quality of SRC as a habitat for animals and plants, depending on the woody species over several years and the management is required. In the years 2010 and 2011, the diversity of ground beetles of willow and poplar in SRC were examined using pitfall traps at three sites in southwestern Germany. It was distinguished between species, variety and age of the SRC. At all sites ground beetle diversity was significantly higher in the studied poplar stands than in those of the willows. In addition, significant differences between the varieties could be observed depending on the location and the year of examination. The older stands of the SRC showed in general a higher level of diversity. Due to the different variety preference of ground beetles it is recommended to plant a mixture of varieties. Furthermore, SRC of different ages should be established side by side, as with increasing tree age species of the open area decrease and forest species settle. Overall, SRC offer the potential to increase biodiversity in natural landscapes. 相似文献
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Faisal Khan Frieder Enzmann Michael Kersten Andreas Wiegmann Konrad Steiner 《Journal of Soils and Sediments》2012,12(1):86-96
Purpose
The purpose of this hydropedological work is to investigate the feasibility of a method to calculate permeability of soil peds on the matrix pore scale resolution. This paper focuses on imaging of the intra-aggregate microstructure and, based on the three-dimensional (3D) images, quantification of the pore network connectivity and permeability tensor. Finally, lattice Boltzmann equation (LBE) simulations of Navier–Stokes flow in the thus derived pore network allow to compute the heterogeneous 3D flow velocity field. 相似文献4.
Studies of the ultrastructure and morphogenesis of fish pathogenic viruses grown in cell culture 总被引:2,自引:0,他引:2
A birnavirus (infectious pancreatic necrosis virus, IPNV), three rhabdoviruses (viral haemorrhagic septicaemia virus, VHSV; infectious haematopoietic necrosis virus, IHNV; and spring viraemia of carp virus, SVCV) and an iridovirus (isolate from a sheatfish) were investigated with regard to their morphogenetic interactions with cells in culture. In cells infected with birnavirus, a granular viromatrix, single virions randomly distributed in the cytoplasm, viral particles aggregated in pseudocrystals and cytoplasmic tubuli similar in diameter to that of the virus were found. Rhabdoviruses entered the cells by viropexis and replicated within the cytoplasm. Maturation occurred predominantly at the cell membrane and sporadically at membranes of the Golgi cisternae. Inclusion bodies were found partially consisting of viral nucleocapsids. After budding, new virions were found adsorbed to the cell membrane. Viral haemorrhagic septicaemia virus, known to exhibit an atypical shape because of preparative procedures, could be identified by immunostaining using two monoclonal antibodies directed against G- and N-proteins and colloidal gold. Iridoviruses entered the cells by viropexis. Viral particles were found in coated vesicles. Subsequently, vesicles without a clathrin coat were detected. Replication occurred within prominent cytoplasmic inclusion bodies. Isometric viral nucleocapsids were transported in an unknown manner to the cell membrane and matured by budding. 相似文献
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Wiebke Züghart Armin Benzler Frank Berhorn Ulrich Sukopp Frieder Graef 《Euphytica》2008,164(3):845-852
According to Directive 2001/18/EC commercial cultivation of genetically modified plants (GMPs) have to be monitored. The aim
of the monitoring is to identify potential adverse effects of the GMPs and their use on human health and the environment.
There are few concepts showing how GMP monitoring may be implemented. This article indicates monitoring requirements with
a focus on environmental issues. GMP monitoring has to be appropriate to detect direct and indirect, immediate and long-term
as well as unforeseen effects. For choosing suitable monitoring indicators and methods, we propose a case-by-case approach,
which is hypothesis-driven and related to specified protection targets. We present criteria for selecting suitable monitoring
sites and demonstrate possibilities to integrate GMP monitoring with existing environmental monitoring programmes. To ensure
comparability, interpretability and quality of GMP monitoring data a harmonisation on both national and international level
is proposed. 相似文献
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