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41.
Abstract

A general characteristic of chemical risk on plant production farms in Poland is presented. The paper describes risk associated with the natural occurrence of chemical substances (such as ammonium and hydrogen sulfide) in the process of animai breeding and risk connected with the use of artificial fertilizers and pesticides. Pesticides are briefly described taking into consideration toxicity classes and the toxic effect of individual compounds. Exposure to pesticides is presented for individual methods and related activities. Finally, the author discusses pesticide risk on fruit-growing farms and in greenhouses.  相似文献   
42.
The Niepo?omice Forest, a large forest complex (11,000 ha), situated about 20 km from a large steel mill and about 40 km from the city of Cracow was the object of study. Sulphur dioxide emitted by the steel mill and the city has already caused acidification of the environment of the Niepo?omice Forest. The degree of such acidification was estimated using tree bark as a bioindicator. The pH value and buffer capacity were determined for three tree species — Quercus robur, Tilia cordata and Pinus sylvestris. The bark of all trees showed acidic reaction ranging from pH 2.2 to 4.7. Difference in pH of bark were found between various localities. The bark of examined species was much more acidic in the western part in the Niepoo?mice Forest than in the eastern part of the forest complex. The buffer capacity of bark also differs in various localities increasing with SO2 concentration in the air. A good correlation between acidification of tree bark and the concentration of SO2 in the air of Niepo?omice Forest was found; therefore tree bark may be regarded as a good bioindicator and recommended for practical use to estimate the degree of air pollution. The procedure of sampling and analysis of tree bark is described in detail.  相似文献   
43.
Addressing environmental problems in estuaries is a worldwide problem. Establishing benchmarks and targets for management is critical, whether the aim is conservation, restoration or sustainable use. Palaeoecological techniques have rapidly improved during the past decade, particularly with advances in methods that allow high resolution quantitative assessments of environmental change. Palaeoecology is a useful tool in environmental management as it allows pre-impact conditions, the rate, extent, direction and cause of change, and range of natural variability to be determined. Australian estuarine ecosystems are qualitatively different from the often more well-studied estuaries in North America and Europe, which means site-specific studies of Australian estuaries are needed to inform management. While a potentially useful and valuable tool, palaeoecological techniques have not yet been widely adopted and practically implemented as part of estuarine management strategies and policy frameworks in Australia.  相似文献   
44.
This study aimed at cross-border mapping metal loads in mosses in eight European countries in 1990, 1995, and 2000 and at investigating confounding factors. Geostatistics was used for mapping, indicating high local variances but clear spatial autocorrelations. Inference statistics identified differences of metal concentrations in mosses on both sides of the national borders. However, geostatistical analyses did not ascertain discontinuities of metal concentrations in mosses at national borders due to sample analysis in different laboratories applying a range of analytical techniques. Applying Classification and Regression Trees (CART) to the German moss data as an example, the local variation in metal concentrations in mosses were proved to depend mostly on different moss species, potential local emission sources, canopy drip and precipitation.  相似文献   
45.
This study was designed to evaluate the measuring range and lowest limit of detection of Bacillus endospores in the ambient room air when the Sartorius MD8 sampler, and two different culture methods for bacterial enumeration were used. Different concentrations of bioaerosol were generated inside the test chamber filled with either the high-efficiency particulate air (HEPA)-filtered air or with the ambient room air. The detection of endospores in the HEPA-filtered air was achievable: (1) when they were aerosolized at a concentration above 7.56?×?103 CFU/m3 and analyzed with spread plate method, and (2) when they were aerosolized at a concentration above 4.00?×?102 CFU/m3 and analyzed with pour plate method. The detection of endospores in the ambient room air was possible: (1) when they were aerosolized at a concentration above 9.1?×?103 CFU/m3 and analyzed with spread plate method, and (2) when they were aerosolized at a concentration above 5.6?×?102 CFU/m3 and analyzed with pour plate method. The microorganisms present in the ambient room air interfere with precise quantification of Bacillus endospores when their concentration is relatively low. The results of this study may be helpful in critical assessment of the results obtained from monitoring the air for bacterial endospores.  相似文献   
46.
Environmental and Ecological Statistics - Cetacean abundance estimation often relies on distance sampling methods using shipboard visual line-transect surveys, which assumes that all animals on the...  相似文献   
47.
Small-holder farmers often develop adaptable agroforestry management techniques to improve and diversify crop production. In the cocoa growing region of Ghana, local knowledge on such farm management holds a noteworthy role in the overall farm development. The documentation and analysis of such knowledge use in cocoa agroforests may afford an applicable framework to determine mechanisms driving farmer preference and indicators in farm management. This study employed 12 in-depth farmer interviews regarding variables in farm management as a unit of analysis and utilized cognitive mapping as a qualitative method of analysis. Our objectives were (1) to illustrate and describe agroforestry management variables and associated farm practices, (2) to determine the scope of decision making of individual farmers, and (3) to investigate the suitability of cognitive mapping as a tool for assessing local knowledge use. Results from the cognitive maps revealed an average of 16 ± 3 variables and 19 ± 3 links between management variables in the farmer cognitive maps. Farmer use of advantageous ecological processes was highly central to farm management (48% of all variables), particularly manipulation of organic matter, shade and food crop establishment, and maintenance of a tree stratum as the most common, highly linked variables. Over 85% of variables included bidirectional arrows, interpreted as farm management practices dominated by controllable factors, insofar as farmers indicated an ability to alter most farm characteristics. Local knowledge use on cocoa production revealed detailed indicators for site evaluation, thus affecting farm preparation and management. Our findings suggest that amid multisourced information under conditions of uncertainty, strategies for adaptable agroforestry management should integrate existing and localized management frameworks and that cognitive mapping provides a tool-based approach to advance such a management support system.  相似文献   
48.
The aim of this work was to assess dietary risk resulting from consumption of polycyclic aromatic hydrocarbons (PAHs) with tea infusions. To this end, levels of 28 PAHs in black, green, red and white teas available on the Polish retail market have been assessed. Profiles and correlation between concentrations of individual PAHs have been identified. A model study on transfer of PAHs from tea leaves into tea preparations has been conducted. Relatively high concentrations of 28 evaluated PAHs have been found in 58 tested samples of black, green, red and white teas sampled on the Polish retail market. Total concentration ∑28PAH ranged from 57 to 696 µg kg?1 with mean 258 µg kg?1 (dry tea leaves). The most mature tea leaves fermented to a small degree contained relatively the highest PAH levels among all four tested tea types. Relatively low PAH transfer rates into tea infusions and limited volumes of the consumed tea keep the risks associated with PAH dietary intake at a safely low level.

The worst-case scenario dietary intake values were 7.62/0.82/0.097 ng kg?1 b.w. day?1 (estimated on the basis of the maximum found concentrations 696/113/23 µg kg?1 and maximum observed transfer rates 24/16/9%) for ∑28PAH/∑PAH4/B[a]P, respectively. MOE values calculated using the above worst case estimates exceeded 700,000 and 400,000 (BMDL10 0.07 and 0.34 mg kg?1 b.w. day?1) for B[a]P and PAH4, respectively. Both B[a]P and PAH4 concentrations may be used as indicators of total PAH concentration in tea leaves; PAH4 slightly better fits low molecular weight PAHs. Several correlations between various PAHs/groups of PAHs have been identified, the strongest one (R2 = 0.92) between PAH4 and EU PAH 15+1.  相似文献   
49.
50.
A case of mosaicism involving structural abnormality of chromosome 18 found in cultured amniotic fluid is reported.  相似文献   
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