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101.
Water scarcity, especially in the hydrologically critical part of the year, is a problem often present in many cities and regions, particularly in arid and sub-arid areas. Climate change and human water demand compound the problem. This paper discusses a climate change adaptation measure—the possibility of karst spring overexploitation, where there is a siphon-shaped cavity inside the mountain. The pilot area is near the city of Ni?, where a decreasing precipitation trend has already been observed and is expected to continue in the future. The paper also presents some basic information related to the pilot area and undertaken investigations. The project, successfully implemented in 2004, has provided the city of Ni? with an additional amount of 200 l/s of spring water during the most critical part of the year.  相似文献   
102.
Harsh and unpredictable environments have been assumed to favor the evolution of better learning abilities in animals. At the same time, individual variation in learning abilities might be associated with variation in other correlated traits potentially forming a behavioral syndrome. We have previously reported significant elevation-related differences in spatial memory and the hippocampus in food-caching mountain chickadees. Here, we tested for elevation-related differences in novel environment exploration, neophobia, and social dominance—behavioral traits previously thought to correlate with individual variation in cognition, using different birds from the same elevations. Compared to low-elevation birds, high-elevation chickadees were slower at novel environment exploration, but there were no detectable differences in neophobia. High-elevation chickadees were also socially subordinate to low-elevation chickadees in pairwise interactions. Considering previously reported elevation-related differences in cognition and the brain, our results suggest, however indirectly, that elevation-related variation in spatial memory might be associated with differences in novel environment exploration and in ability to obtain a high social rank in winter social groups. Whether these behavioral traits represent a behavioral syndrome or whether climate might affect these traits independently, our results suggest that multiple differences between elevations might assist with elevation-related separation. High-elevation chickadees would likely experience higher mortality if they move to lower elevation due to their low social dominance status and low-elevation chickadees might experience higher mortality if they move to higher elevation due to reduced memory ability and lack of behavioral adaptations to colder climate.  相似文献   
103.
The individual-based stand-level model EFIMOD was used for large-scale simulations using standard data on forest inventories as model inputs. The model was verified for the case-study of field observations, and possible sources of uncertainties were analysed. The approach developed kept the ability for fine-tuning to account for spatial discontinuity in the simulated area. Several forest management regimes were simulated as well as forest wildfires and climate changes. The greatest carbon and nitrogen accumulations were observed for the regime without cuttings. It was shown that cuttings and wildfires strongly influence the processes of carbon and nitrogen accumulations in both soil and forest vegetation. Modelling also showed that the increase in annual average temperatures resulted in the partial relocation of carbon and nitrogen stocks from soil to plant biomass. However, forest management, particularly harvesting, has a greater effect on the dynamics of forest ecosystems than the prescribed climate change.  相似文献   
104.
This study investigated concentrations of PM2.5, PM10, SO2, NO2, CO and O3, and air quality index(AQI) values across 368 cities in mainland China during 2015–2018. The study further examined relationships of air pollution status with local industrial capacities and vehicle possessions. Strong correlations were found between industrial capacities(coal, pig iron, crude steel and rolled steel) and air pollution levels. Although statistical and ...  相似文献   
105.
Data on content of (90)Sr, (137)Cs, (239,240)Pu and (3)H in water of the Tobol-Irtysh part of the Techa-Iset-Tobol-Irtysh-Ob river system (through which the "Mayak" PA radioactive wastes are transported) are presented and discussed. The data were received in 2004-2005 under the ISTC project on radioecological monitoring of the Tobol and Irtysh rivers. Monthly observations of (137)Cs, (90)Sr and (3)H content in water in the area of the Tobol and Irtysh confluence have been conducted starting from May 2004. To obtain information on the investigated river system as a whole, the radioecological survey of the Tobol and Irtysh rivers at the section from the mouth of the Iset River to the confluence with the Ob River was carried out in 2004. It is shown that the impact of "Mayak" PA waste transport by (90)Sr is distinctly traced as far as the area of the Irtysh and Ob confluence.  相似文献   
106.

In vivo laboratory studies of toxicity were performed on Wistar rats using a methanol extract produced by the natural population of Cylindrospermopsis raciborskii (abundance of 2.13 × 105 trichomes mL−1) collected at Aleksandrovac Lake (Serbia). HPLC analysis showed that the extract contains 6.65 μg cylindrospermopsin (CYN) mg−1. The rats were killed 24 or 72 h after a single intraperitoneal injection of C. raciborskii extract in concentrations of 1500, 3000, 6000 and 12,000 μg kg−1 body weight (bw) and an equivalent amount of CYN as present in the highest dose of the extract (79.80 μg CYN kg−1 bw). The genotoxic effect on the livers treated with C. raciborskii was evaluated using comet assay and potential induction of oxidative stress as the toxicity mechanism associated with the presence of CYN in extract. The results from the analyses of DNA damage in the comet tail length, tail moment and percentage of DNA in the tail in the liver indicated that administration of extract and CYN present statistically significant difference when compared with the negative control group. Although an increase in the frequency of selected parameters induced by the CYN was observed in the liver, this damage was less than the damage resulting from the administration of the highest dose of extract. The changes in the biochemical parameters of the hepatic damage showed that the application of single doses of the extract and CYN did not cause serious liver damage in rats. The extract and CYN significantly increased oxidative stress in rats’ liver after a single exposure.

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107.
108.
Mitigation and Adaptation Strategies for Global Change - This work aims to assess the dynamics of net greenhouse gas (GHG) emissions and removals, as well as analyse the mitigation potential for...  相似文献   
109.
Paper sludge is a waste product from the paper and pulp manufacturing industry that is generally disposed of in landfills. Pyrolysis of paper sludge can potentially provide an option for managing this waste by thermal conversion to higher calorific value fuels, bio-gas, bio-oils and charcoal. This work investigates the properties of paper sludge during pyrolysis and energy required to perform thermal conversion. The products of paper sludge pyrolysis were also investigated to determine their properties and potential energy value. The dominant volatile species of paper sludge pyrolysis at 10 °C/min were found to be CO and CO2, contributing to almost 25% of the paper sludge dry weight loss at 500 °C. The hydrocarbons (CH4, C2H4, C2H6) and hydrogen contributed to only 1% of the total weight loss. The bio-oils collected at 500 °C were primarily comprised of organic acids with the major contribution being linoleic acid, 2,4-decadienal acid and oleic acid. The high acidic content indicates that in order to convert the paper sludge bio-oil to bio-diesel or petrochemicals, further upgrading would be necessary. The charcoal produced at 500 °C had a calorific value of 13.3 MJ/kg.  相似文献   
110.
Caching species can manage their energy supply by adjusting body fat, number of caches, or both. It has been hypothesized that because body fat has a higher fitness cost than caches, small food-hoarding birds respond to increased starvation risk by increasing the number of their caches rather than their fat load. This hypothesis predicts that when birds cannot cache they should compensate for the loss of external energy storage by (1) shifting the time of their daily body mass accumulation toward earlier in the day and (2) increasing the overall level of their fat reserves. During the winter of 1995–1996, we tested these predictions with a caching species, the tufted titmouse (Parus bicolor). Each of six experimental birds was fed a diet of uncachable sunflower seed powder for 6 days, preceded and followed by 6-day control periods during which they were fed cachable sunflower seeds. The daily pattern of body mass gain was unaffected by the opportunity to cache. Furthermore, when unable to cache, the birds did not increase either their mean daily body mass, body mass in the middle of the day, or evening body mass compared to the two control periods. These results argue against the hypothesis of a trade-off between fat reserves and food caches in tufted titmice, and suggest that fat reserves are managed independently of external food caches. Received: 9 April 1997 / Accepted after revision: 30 August 1997  相似文献   
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