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1.
European forestry is facing many challenges, including the need to adapt to climate change and an unprecedented increase in forest damage. We investigated these challenges in a Norway spruce-dominated mountain region in Central Europe. We used the model Sibyla to explore forest biomass production to the year 2100 under climate change and under two alternative management systems: the currently applied management (CM), which strives to actively improve the forest’s adaptive capacity, and no management (NM) as a reference. Because biodiversity is thought to have mostly positive effects on the adaptive capacity of forests and on the quality of ecosystem services, we explored how climate change and management affect indicators of biodiversity. We found a differential response across the elevation-climatic gradient, including a drought-induced decrease in biomass production over large areas. With CM, the support of non-spruce species and the projected improvement of their growth increased tree species diversity. The promotion of species with higher survival rates led to a decrease in forest damage relative to both the present conditions and NM. NM preserved the high density of over-matured spruce trees, which caused forest damage to increase. An abundance of dead wood and large standing trees, which can increase biodiversity, increased with NM. Our results suggest that commercial spruce forests, which are not actively adapted to climate change, tend to preserve their monospecific composition at a cost of increased forest damage. The persisting high rates of damage along with the adverse effects of climate change make the prospects of such forests uncertain.  相似文献   
2.
Environmental Science and Pollution Research - The most common mycotoxin found in European foodstuffs, especially unprocessed grains, is deoxynivalenol (DON), which inhibits proteosynthesis and...  相似文献   
3.
It is demonstrated that biological species like limpets can be classified according to their level of n-alkanes when artificial neural networks are applied. Marine intertidal and subtidal limpets of the Canary Islands (Spain), Patella piperata, Patella candei crenata and Patella ulyssiponensis aspera were selected as bioindicator organisms. Samples were collected at four stations on the coasts of Fuerteventura. Concentration of n-alkanes in the soft tissues of the limpets has been determined by gas chromatography. Data were treated with artificial neural networks (ANNs) and it was found that using suitable architecture of a supervised artificial neural network, the limpets can be successfully distinguished (classified) up to 98%.  相似文献   
4.
Fertilization by phosphorus and also nitrogen fertilizers are the main source of cadmium soil contamination. Cadmium is relatively easily taken up by plants and then consequently enters their food chain. We investigated whether the cultivation medium with or without sulphates supplement affects the synthesis of protective low molecular mass thiols such as cysteine, reduced glutathione, oxidized glutathione and phytochelatins (PC2) in Dionaea muscipula treated with cadmium(II) ions at 0, 1, 5, 10, 25, 50, 100, 250, 500 and 1,000 μM for 6 weeks. The plants cultivated in the presence of sulphates showed higher cadmium tolerance due to faster growth and lesser number of necrosis hallmarks. Further, we utilized liquid chromatography with electrochemical detection for determination of the thiols in plant tissues. In the case of the plants cultivated on media supplemented with sulphates for 6 weeks the average PC2 level was 2,830 ng/g of fresh weight (FW). However, the plants cultivated on media without the presence of sulphates on average contained 1,160 ng PC2/g FW. Results obtained showed the positive effect of sulphur supplementation in cadmium detoxification processes in plants. In addition to thiol content, we also determined level of majority secondary metabolite of Venus flytrap, naphthoquinone plumbagin. Generally, the presence of sulphates in the media enhanced the protective mechanism and did not affect directly the synthesis of secondary metabolite plumbagin.  相似文献   
5.
Mass spectrometry fingerprinting of humic acids extracted from different soils has been carried out using laser desorption/ionization mass spectrometry (LDI-TOF MS). LDI-TOF MS provides characteristic mass spectra fingerprints for the humic acids of different origin. The information given in the fingerprints was evaluated for natural grouping trends in the samples by neural networks computing tools, such as self-organizing feature map (SOFM). This approach is efficient for recognizing patterns in the humic acids samples independently of their characteristic variability; variability characterizing natural products such as humic substances. The use of multi-layer perceptron artificial neural networks gave a successful classification of the samples.  相似文献   
6.
Thirty different white rot strains were screened for Orange G and Remazol Brilliant Blue R (RBBR) decolorization on agar plates. Three promising strains, Dichomitus squalens, Ischnoderma resinosum and Pleurotus calyptratus, selected on the basis of this screening, were used for decolorization study in liquid media. All three strains efficiently decolorized both Orange G and RBBR, but they differed in decolorization capacity depending on cultivation conditions and ligninolytic enzyme production. Two different decolorization patterns were found in these strains: Orange G decolorization in I. resinosum and P. calyptratus was caused mainly by laccase, while RBBR decolorization was effected by manganese peroxidase (MnP); in D. squalens laccase and MnP cooperated in the decolorization processes.  相似文献   
7.
The effects of air pollution on the genetic structure of Norway spruce, European silver fir and European beech were studied at four polluted sites in Slovakia, Romania and Czech Republic. In order to reduce potential effects of site heterogeneity on the health condition, pair-wise sampling of pollution-tolerant and sensitive trees was applied. Genotypes of sampled trees were determined at 21 isozyme gene loci of spruce, 18 loci of fir and 15 loci of beech. In comparison with Norway spruce, fewer genetic differences were revealed in beech and almost no differentiation between pollution-tolerant and sensitive trees was observed in fir. In adult stands of Norway spruce, sensitive trees exhibited higher genetic multiplicity and diversity. The decline of pollution-sensitive trees may result thus in a gradual genetic depletion of pollution-exposed populations of Norway spruce through the loss of less frequent alleles with potential adaptive significance to altered stressing regimes in the future. Comparison of the subsets of sensitive and tolerant Norway spruce individuals as determined by presence or absence of discolorations ("spruce yellowing") revealed different heterozygosity at 3 out of 11 polymorphic loci.  相似文献   
8.
Investigators have typically relied on a single or few discrete time points as measures of polychlorinated biphenyl (PCB) body burden, however health effects are more likely to be the result of integrative exposure in time, optionally expressed as an area under the time curve (AUC) of PCB serum concentration. Using data from a subgroup of 93 infants from a birth cohort in eastern Slovakia—a region highly polluted by PCBs—we fit a system type model, customized to our longitudinal measures of serum PCB concentrations in cord, 6, 16, and 45 month blood specimens. The most abundant congener, PCB 153, was chosen for modeling purposes. In addition to currently used methods of exposure assessment, our approach estimates a concentration time profile for each subject, taking into account mean residence time of PCB 153 molecules in the body, duration of breast feeding, hypothetical PCB 153 concentration in steady-state without breast feeding and alternately without normal food intake. Hypothetical PCB 153 concentration in steady-state without normal food intake correlates with AUC (r = 0.84, p < 0.001) as well as with duration of breast feeding (r = 0.64, p < 0.001). It makes possible to determine each subject’s exposure profile expressed as AUC of PCBs serum concentration with a minimum model parameters. PCB body burden in most infants was strongly associated with duration of breast feeding in most, but not all children, was apparent from model output.  相似文献   
9.
We present results from measurements by a NILU-UV Irradiance Meter of solar UV-B radiation in Lhasa, Tibet for the period from 7 July 1999 to 17 November 2002. The measured maximum UV-B dose rate was 1.50 W/m2 during the winter, and 3.96 W/m2, during the summer. The clear-sky values were below 3.00 W/m2. Comparisons between measured and calculated UV-B dose rates on clear-sky days in Lhasa show good agreement. Comparisons of UV-B radiation levels in Lhasa (Tibet), Oslo (Norway), and Dar-Es-Salaam (Tanzania) show that the UV-B dose rates during the summer in Lhasa are higher than the maximum value in Dar-Es-Salaam, which is at the sea level in the equatorial region, and 60% higher than in Oslo, which is at the sea level but 60 degrees North. We conclude that the UV-B dose rates during the summer on the Tibetan plateau are among the highest levels in habituated regions of the world. Maximum measured daily-integrated UV-B doses in Lhasa range from about 10 kJ/m2 in the winter to about 65 kJ/m2 in the summer.  相似文献   
10.
Mercury (Hg) concentration profiles and historical accumulation rates were determined in three 210Pb-dated cores from a peat deposit in the vicinity of a lead (Pb) smelter at Příbram, Czech Republic. The Hg concentrations in peat samples ranged from 66 to 701 μg kg−1. Cumulative Hg inventories from each core (for the past 150 yr) varied by a factor of 1.4 (13.6–18.5 mg Hg m−2), indicating variations of net Hg accumulation rate within the peat deposit. Historical changes in vegetation cover (leading to variable interception by trees) are probably responsible for this variation in space and time. The uncorrected Hg accumulation rates peaked between the 1960s and 1980s (up to 226 μg m−2 yr−1). Recent findings show that Hg records from peat tend to overestimate historical levels of Hg deposition. Therefore we used the mass loss compensation factor (MLCF) to normalize Hg accumulation rates. These corrected Hg accumulation rates were significantly lower (maximum 129 μg m−2 yr−1) and better corresponded to changes in historical smelter emissions, which were highest in the 1960s. The agreement between the corrected Hg accumulation rates in the uppermost peat sections (2–38 μg m−2 yr−1) and biomonitoring of atmospheric deposition by mosses in several recent years (4.7–34.4 μg m−2 yr−1) shows the usefulness of MLCF application on Hg accumulation in peat archives. However, the MLCF correction was unsuitable for Pb. The recent Pb deposition rates obtained by an independent biomonitoring study using mosses (0.5–127 mg m−2 yr−1) were better correlated with net Pb accumulation rates recorded in peat (7–145 mg m−2 yr−1) than with corrected rates obtained by the MLCF approach (1–28 mg m−2 yr−1).  相似文献   
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