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81.
An extracellular H2O2-requiring Remazol Brilliant Blue R (RBBR) decolorizing enzyme activity was detected after cultivation of cells of various plant species both in liquid medium and when growing on agar plates containing RBBR. Level of the enzyme activity was compared with the ability to metabolize polychlorinated biphenyls (PCBs). The ability to decolorize RBBR was tested in the presence and absence of PCBs. The cultures with high PCB-transforming activity proved to exhibit RBBR oxidase much more resistant towards the influence of PCBs. In addition low activities of lignin peroxidase (LiP) and manganese dependent peroxidase (MnP) were detected in medium and in plant cells. No correlation of MnP and LiP activities with PCB degradation could be found. The RBBR decolorization could be used as a rough screening method for plant cultures able to metabolize PCBs. 相似文献
82.
Knowledge of the relationship between species traits and species distribution in fragmented landscapes is important for understanding current distribution patterns and as background information for predictive models of the effect of future landscape changes. The existing studies on the topic suffer from several drawbacks. First, they usually consider only traits related to dispersal ability and not growth. Furthermore, they do not apply phylogenetic corrections, and we thus do not know how considerations of phylogenetic relationships can alter the conclusions. Finally, they usually apply only one technique to calculate habitat isolation, and we do not know how other isolation measures would change the results. We studied the issues using 30 species forming congeneric pairs occurring in fragmented dry grasslands. We measured traits related to dispersal, survival, and growth in the species and recorded distribution of the species in 215 grassland fragments. We show many strong relationships between species traits related to both dispersal and growth and species distribution in the landscape, such as the positive relationship between habitat occupancy and anemochory and negative relationships between habitat occupancy and seed dormancy. The directions of these relationships, however, often change after application of phylogenetic correction. For example, more isolated habitats host species with smaller seeds. After phylogenetic correction, however, they turn out to host species with larger seeds. The conclusions also partly change depending on how we calculate habitat isolation. Specifically, habitat isolation calculated from occupied habitats only has the highest predictive power. This indicates slow dynamics of the species. All the results support the expectation that species traits have a high potential to explain patterns of species distribution in the landscape and that they can be used to build predictive models of species distribution. The specific conclusions are, however, dependent on the technique used, and we should carefully consider this when comparing among different studies. Since different techniques answer slightly different questions, we should attempt to use analyses both with and without phylogenetic correction and explore different isolation measures whenever possible and compare the results. 相似文献
83.
Lal AA Murthy PB Pillai KS 《Journal of environmental biology / Academy of Environmental Biology, India》2007,28(2):201-207
The hepatoprotective potential of a herbal mixture was evaluated against CCl4 induced liver injury in Swiss albino mice. Liv 52, a commercially available polyherbal hepatoprotective drug was evaluated for comparison. The potential toxicity of the above herbal hepatoprotective agents was also compared. It was observed that there was a reduction in the enzyme biomarkers (Aspartate and Alanine Transaminase) of liver injury in the herbal mixture treated groups, which was similar to the reduction initiated by Liv 52. An increase in glutathione was observed in the herbal mixture treated groups and it was assumed that the herbal mixture protects the liver by virtue of its antioxidant nature along with high regeneration initiation potential. From the study it is also concluded that the herbal mixture is safer than Liv 52. 相似文献
84.
Clarifying the role of fire in the deciduous forests of eastern North America: reply to Matlack 下载免费PDF全文
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Patoucheas Pierros Koukousioura Olga Psarra Stella Aligizaki Katerina Dimiza Margarita D. Skampa Elisavet Michailidis Ioannis Nomikou Paraskevi Triantaphyllou Maria V. 《Environmental science and pollution research international》2021,28(26):33854-33865
Environmental Science and Pollution Research - Phytoplankton community was investigated during two contrasting periods using offshore plankton samples in the volcanic area of Methana peninsula... 相似文献
89.
The COVID-19 pandemic is a global crisis emanating both from a virus (SARS-CoV-2) and from the drastic actions to contain it. Here, we reflect on the immediate responses of most world powers amid the pandemic chaos: totalitarian surveillance and nationalist isolation. Drawing on published literature, we consider measures such as wildlife-use bans, lockdowns and travel restrictions, along with their reverberations for people, economies and the planet. Our synthesis highlights significant shortfalls of applying command-and-control tactics in emergencies. For one, heavy-handed bans risk enormous unintended consequences and tend to fail if they lack legitimacy or clash with people’s values. Furthermore, reactive and myopic strategies typically view the pandemic as a stand-alone crisis, rather than unravelling the complex interplay of nature-society interactions through which zoonotic diseases originate. A return to adaptive management approaches that recognise root causes and foster socio-ecological resilience will be essential to improve human and planetary health and mitigate future pandemics. 相似文献