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121.
122.
Goal, Scope and Background
The release of genetically modified organisms (GMOs) may result in ecological impacts to be monitored. This series presents the state-of-art concerning the environmental monitoring of ecological impacts of GMOs. Since this monitoring is conducted by several authorities, the methodical comparability and spatial validity of the monitoring data is crucial. Thus, the respective fundamentals of philosophy of science and of statistics as well as the methodical standardisation form the focus of this article.Main Features
At first, the monitoring requirements will be described from the viewpoint of ecology. Consequently, the GMO monitoring needs to be integrated into existing programmes. Exposure and effects of GMOs have to be monitored across the hierarchy of ecological organisation. For monitoring to be efficient and sufficient, the design must be founded in terms of philosophy of science and statistics. Hence the fundamentals concerning the verification of hypotheses represent another feature of this article. The data used for the verification of hypotheses must comply with quality criteria. One of these criteria is the spatial and temporal extrapolation of the monitoring results, which is the third feature in this introductory article.Conclusions
The evaluation of hypotheses on GMO impacts requires the linkage to ecosystems research and environmental monitoring. These both are, in terms of methodology, complementary and of significant technical and scientific value for GMO monitoring.Recommendations
GMO-monitoring should closely be connected with ecosystems research and environmental monitoring. The levels of ecological organisation should be covered as well as the exposure and the effects of GMOs. The expected GMO exposure and effects should be considered by localising the monitoring sites.Perspectives
Further articles of this series will deal with network designing, GMO pollen monitoring and extrapolation of site-specific measurements and modelling results. 相似文献123.
Along the west coast of North America, the invasive mussel Mytilus galloprovincialis and a native congener M. trossulus overlap in range and compete for habitat in an extensive hybrid zone along central California. The two species have been
shown to exhibit differential abiotic tolerances in laboratory studies, yet little is known about how such tolerances affect
spatial and temporal patterns of geographic distribution, particularly in areas of competition. We examined distributions
of the two congeners and their hybrids in neighboring intertidal and subtidal habitats in Bodega Bay, CA over 2 years, and
compared shell length and seasonal ubiquitin (Ub) conjugates to estimate protein turnover and physiological stress for the
species at each site. The two species were spatially segregated, with M. galloprovincialis dominating the subtidal habitat, and M. trossulus constituting a majority of the intertidal mussel population. Hybrid individuals appeared in low numbers at both sites. For
each habitat, there was no statistical difference between shell lengths of M. galloprovincialis and hybrids but M. trossulus mussels were statistically smaller than the other two. In regards to physiological performance, ubiquitin conjugate values
showed different seasonal cycles for the two species, suggesting different periods of peak environmental stress. The highest
levels of Ub-conjugated proteins were observed in winter for M. galloprovincialis and in summer for M. trossulus, consistent with the respective range edges for their distributions since Bodega Bay is near the northern range edge of the
invader and the southern edge of the native species. These findings suggest that future assessments of Mytilus populations along the California coast may need to consider vertical distributions and seasonal cycles as part of monitoring
and research activities. 相似文献
124.
Michael R. Kidd Peter D. Dijkstra Callison Alcott Dagan Lavee Jacqualine Ma Lauren A. O’Connell Hans A. Hofmann 《Behavioral ecology and sociobiology》2013,67(8):1307-1315
Hormones play an important role in the regulation of reproductive behavior. Here, we examined the effects of the fatty acid derivative prostaglandin F2α (PGF2) on female sexual behavior as well as the interaction between PGF2-induced mating behavior with male courtship display in the lek-breeding African cichlid fish, Astatotilapia burtoni. In a two-way choice paradigm, we found that nonreproductive females preferred to associate with smaller, less aggressive males over larger, more aggressive males. However, PGF2-treated females dramatically reversed their preference to larger males. In a second experiment, PGF2 treatment dramatically increased sexual behavior in nonreproductive females as measured by time spent in the bower of the stimulus male, even when the female and the stimulus male were separated by a transparent divider. This effect was even more pronounced when the stimulus males were exposed to the putative female pheromone 17α,20β-progesterone (17α,20β-P). Under full-contact conditions, only PGF2-treated females visited a stimulus male’s bower, where they even displayed circling behavior usually only seen during spawning. Interestingly, male performance prior to PGF2 treatment predicted female sexual response. Our study demonstrates the importance of PGF2 in the control of female reproductive behavior in interaction with male performance. 相似文献
125.
In this study the runoff of (137)Cs, mainly originated from the Chernobyl fallout, from highly contaminated alpine regions in Salzburg (Austria) is discussed. Twenty-five water-samples and 25 sediment-samples were taken from creeks of different size to determine the runoff of dissolved (137)Cs and Cs-binding characteristics to different particle size classes in the sediments. The hypothesis, that specific activity of the sediments depended on particle size and the surface of the particle, was proved with some modifications. Caesium activity concentration in water showed a negative correlation with electrical conductivity, while no significant correlations were detectable with other variables (pH, temperature, and altitude). Enormous differences and the variations found in the (137)Cs-concentrations in water can be explained by the electrical conductivity without any dependency on the inventory of the catchment. The sediment samples analysed showed a negative correlation between specific activity [Bq/kg] and particle-diameter, mainly explained by (137)Cs-uptake proportional to the particle surface per mass. 相似文献
126.
127.
Relatively high concentrations of phenol, p-cresol, phenylacetic acid and other aromatic compounds were found in agricultural and communal sewage deposits. These toxic aromatic compounds are products of the bacterial degradation of aromatic amino acids under anaerobic conditions. In laboratory experiments at 26 degrees C and under N2-atmosphere, the same aromatics were formed from the amino acid tyrosine and from gelatine in assays inoculated with sewage sludge. After exhaustion of tyrosine and gelatine, respectively, concentrations of the accumulated phenol and other aromatics remained stable for months, i.e., phenol, p-cresol, phenylacetic acid etc. are dead-end products of the bacterial metabolism under these conditions. After addition of sodium nitrate the aromatic compounds are metabolically decomposed by denitrification within weeks. 相似文献
128.
Max Hofmann Laetitia M. Navarro Steve Carver Peter H. Verburg Henrique M. Pereira 《Conservation biology》2015,29(4):1017-1027
Farmland abandonment takes place across the world due to socio‐economic and ecological drivers. In Europe agricultural and environmental policies aim to prevent abandonment and halt ecological succession. Ecological rewilding has been recently proposed as an alternative strategy. We developed a framework to assess opportunities for rewilding across different dimensions of wilderness in Europe. We mapped artificial light, human accessibility based on transport infrastructure, proportion of harvested primary productivity (i.e., ecosystem productivity appropriated by humans through agriculture or forestry), and deviation from potential natural vegetation in areas projected to be abandoned by 2040. At the continental level, the levels of artificial light were low and the deviation from potential natural vegetation was high in areas of abandonment. The relative importance of wilderness metrics differed regionally and was strongly connected to local environmental and socio‐economic contexts. Large areas of projected abandonment were often located in or around Natura 2000 sites. Based on these results, we argue that management should be tailored to restore the aspects of wilderness that are lacking in each region. There are many remaining challenges regarding biodiversity in Europe, but megafauna species are already recovering. To further potentiate large‐scale rewilding, Natura 2000 management would need to incorporate rewilding approaches. Our framework can be applied to assessing rewilding opportunities and challenges in other world regions, and our results could guide redirection of subsidies to manage social‐ecological systems. 相似文献
129.
The lack of microbial degradation of polycyclic aromatic hydrocarbons from coal-rich soils 总被引:1,自引:0,他引:1
Achten C Cheng S Straub KL Hofmann T 《Environmental pollution (Barking, Essex : 1987)》2011,159(2):623-629
Analytical techniques used to assess the environmental risk of contamination from polycyclic aromatic hydrocarbons (PAHs) typically consider only abiotic sample parameters. Supercritical fluid extraction and sorption enthalpy experiments previously suggested slow desorption rates for PAH compounds in two coal-contaminated floodplain soils. In this study, the actual PAH availability for aerobic soil microorganisms was tested in two series of soil-slurry experiments. The experimental conditions supported microbial degradation of phenanthrene if it was weakly sorbed onto silica gel. Native coals and coal-derived particles in two soils effectively acted as very strong sorbents and prevented microbial PAH degradation. The long history of PAH exposure and degree of coal contamination apparently had no influence on the capability of the microbial soil community to overcome constraints of PAH availability. Within the context of the experimental conditions and the compounds chosen, our results confirm that coal-bound PAHs are not bioavailable and hence of low environmental concern. 相似文献