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31.
Total concentrations of Cd, Cr, Fe, Ni, Pb and Zn were compared from October 1996 to April 1998 in Physcia biziana (Massal.) Zhalbr. v. leptophylla Vezda and in the bark of Quercus ilex L. sampled from the same trees at an urban park. Trace metal concentrations were also measured in the bark covered by the lichen thalli. The lichens showed significantly higher Cr, Fe, Ni and Zn concentrations than both uncovered and covered barks. By contrast, both types of barks had higher concentrations of Cd and Pb than lichens. Trace elements showed a wide temporal variation of concentrations both in the lichens and barks. No relationship was found between the analysed matrices as regards the time course of trace element concentrations.  相似文献   
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Fetal magnetic resonance spectroscopy (MRS) is technically feasible in utero and demonstrates similar findings to those observed in neonatal populations. MRS can provide additional information to conventional T1- and T2-weighted imaging of the fetal brain. It is of particular use when subtle changes are present on conventional fetal MRI sequences, and when imaging fetuses at risk of brain injury and metabolic abnormalities. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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The yellow-legged clearwing (YLC) Synanthedon vespiformis (Lepidoptera: Sesiidae) occurs in the Mediterranean and central Europe. It is polyphagous, boring into the woody parts of broadleaf species including forest trees as well as various Rosaceae species. S. vespiformis has been reported as an economically important pest causing severe injury to stone fruit plantations. Many attractants for sesiid species were discovered by random field screening using 2,13- and 3,13-octadecadienyl alcohols, acetates and aldehydes, including one for S. vespiformis; and about 20 sex pheromones of sesiids have been identified so far. In the present study we identified the natural composition of the sex pheromone of YLC laboratory reared females as a blend of E3,Z13- and Z3,Z13-octadecadienyl acetates, at a ratio of 4:1. We developed an efficient lure for monitoring the pest. Pheromone funnel traps with rubber septa, impregnated with 1 mg pheromone blend, efficiently captured males for 10 weeks. Suspension of Shin-Etsu? ropes containing a 2:1 blend of E3,Z13-18:Ac and Z3,Z13-18:Ac at 13.74 mg/ha/h, resulted in shutdown of trap catches in the treated plots and closely situated neighboring plots indicating that mating disruption is feasible.  相似文献   
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Waste management procedures in developing countries are associated with occupational safety and health risks. Gastro-intestinal infections, respiratory and skin diseases as well as muscular-skeletal problems and cutting injuries are commonly found among waste workers around the globe. In order to find efficient, sustainable solutions to reduce occupational risks of waste workers, a methodological risk assessment has to be performed and counteractive measures have to be developed according to an internationally acknowledged hierarchy. From a case study in Addis Ababa, Ethiopia suggestions for the transferral of collected household waste into roadside containers are given. With construction of ramps to dump collected household waste straight into roadside containers and an adaptation of pushcarts and collection procedures, the risk is tackled at the source.  相似文献   
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The giant Mediterranean limpet Patella ferruginea Gmelin, 1791 is an endangered marine gastropod, whose range has progressively shrinked to few, restricted areas, due to intense human exploitation. We have studied the genetic structure of the species, in order to (1) gather information about the levels of genetic variability within and between natural populations of P. ferruginea collected in two Sardinian marine protected areas (MPAs) (Penisola del Sinis—Isola di Mal di Ventre and Isola dell’ Asinara), and (2) make an attempt to find relationships between ecological and biological attributes of the species and the genetic differentiation of the populations studied. The genetic study was carried out by means of the analysis of ten inter-simple sequence repeat (ISSR) primers on a total of 40 individuals collected at four localities. Genetic analysis evidenced (1) medium to high levels of within-population genetic variability, (2) a pattern of genetic structuring that varied with spatial scales, and (3) a strong genetic differentiation between the two MPAs. Although preliminary, these results suggest that gene flow may be present only at very small geographic scale, raising concerns on the future of the conservation of the species.  相似文献   
38.
The spatial scale of life-history and demographic variation was investigated in the opportunistic polychaete Ophryotrocha labronica La Greca and Bacci. Individuals were collected along the Italian coasts from three thermally different biogeographical regions of the Mediterranean Sea. For each region, populations from four harbours were considered, and for each harbour, two sites were examined. Life-history and demographic traits were investigated after one generation under a common garden experiment, and their variation at the three spatial scales was assessed. All the traits showed high variability with regard to site. A number of life-history and all demographic traits also varied according to the biogeographical region. Conversely, no differences were found between harbours, suggesting that geographical isolation did not contribute to phenotypic variation. Results confirmed the central role of local conditions for the evolution of life history in species colonizing heterogeneous environments, but they also pointed to the importance of large-scale factors in shaping the phenotypic responses of O. labronica, demonstrating the need for a multi-scale approach for obtaining a good measure of natural variation in widespread opportunistic species.  相似文献   
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Microbial communities and their associated enzyme activities affect the amount and chemical quality of carbon (C) in soils. Increasing nitrogen (N) deposition, particularly in N-rich tropical forests, is likely to change the composition and behavior of microbial communities and feed back on ecosystem structure and function. This study presents a novel assessment of mechanistic links between microbial responses to N deposition and shifts in soil organic matter (SOM) quality and quantity. We used phospholipid fatty acid (PLFA) analysis and microbial enzyme assays in soils to assess microbial community responses to long-term N additions in two distinct tropical rain forests. We used soil density fractionation and 13C nuclear magnetic resonance (NMR) spectroscopy to measure related changes in SOM pool sizes and chemical quality. Microbial biomass increased in response to N fertilization in both tropical forests and corresponded to declines in pools of low-density SOM. The chemical quality of this soil C pool reflected ecosystem-specific changes in microbial community composition. In the lower-elevation forest, there was an increase in gram-negative bacteria PLFA biomass, and there were significant losses of labile C chemical groups (O-alkyls). In contrast, the upper-elevation tropical forest had an increase in fungal PLFAs with N additions and declines in C groups associated with increased soil C storage (alkyls). The dynamics of microbial enzymatic activities with N addition provided a functional link between changes in microbial community structure and SOM chemistry. Ecosystem-specific changes in microbial community composition are likely to have far-reaching effects on soil carbon storage and cycling. This study indicates that microbial communities in N-rich tropical forests can be sensitive to added N, but we can expect significant variability in how ecosystem structure and function respond to N deposition among tropical forest types.  相似文献   
40.
The international, interdisciplinary biodiversity research project BIOTA AFRICA initiated a standardized biodiversity monitoring network along climatic gradients across the African continent. Due to an identified lack of adequate monitoring designs, BIOTA AFRICA developed and implemented the standardized BIOTA Biodiversity Observatories, that meet the following criteria (a) enable long-term monitoring of biodiversity, potential driving factors, and relevant indicators with adequate spatial and temporal resolution, (b) facilitate comparability of data generated within different ecosystems, (c) allow integration of many disciplines, (d) allow spatial up-scaling, and (e) be applicable within a network approach. A BIOTA Observatory encompasses an area of 1?km2 and is subdivided into 100 1-ha plots. For meeting the needs of sampling of different organism groups, the hectare plot is again subdivided into standardized subplots, whose sizes follow a geometric series. To allow for different sampling intensities but at the same time to characterize the whole square kilometer, the number of hectare plots to be sampled depends on the requirements of the respective discipline. A hierarchical ranking of the hectare plots ensures that all disciplines monitor as many hectare plots jointly as possible. The BIOTA Observatory design assures repeated, multidisciplinary standardized inventories of biodiversity and its environmental drivers, including options for spatial up- and downscaling and different sampling intensities. BIOTA Observatories have been installed along climatic and landscape gradients in Morocco, West Africa, and southern Africa. In regions with varying land use, several BIOTA Observatories are situated close to each other to analyze management effects.  相似文献   
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