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This paper presents the changes of landscape structure in the Dem?novská Valley which ranks among the most valuable protected areas of Slovakia. The area was selected on the basis of changes associated with the rapidly growing tourism industry and the rise of an important destination in the center of Low Tatras National Park, Slovakia. To document any changes, we visually interpreted data from aerial and satellite images in three periods(1949, 2007 and 2013) and for predicting future changes we used land use planning documentation. Interpreted data were analyzed using overlay analysis and landscape metrics. Results showed extensive changes in the landscape structure mainly connected with the development of tourism infrastructure. We also identified long-term changes whose causes stem from the transformation of society and forest management in the past. The dynamics and extent of these changes may increase in the future. We propose to stop future development of ski slopes and expansion of related infrastructure, to focus on sustainability and environmentally friendly operation of the existing ski resort and to invest a substantial portion of profits to support projects aimed to preserve surrounding lands and wildlife.  相似文献   
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Trends in phytoplankton monitoring data (1976–2008) from the Gulf of Riga were investigated and linked to environmental factors. Annual means of spring phytoplankton biomass correlated to phosphorus input from land and shifts between diatoms and dinoflagellates were attributed to potential Si limitation and time of sampling relative to the spring phytoplankton succession. The summer phytoplankton biomass, which more than doubled over the study period, was related to the abundance of summer copepods that similarly declined. Cyanobacterial blooms proliferated in summer and the proportion of diatoms similarly declined when the winter–spring inorganic N/P ratio was low. The chlorophyte proportion in summer increased over the study period, and this was linked to increasing temperatures favoring their higher growth rates. The dinoflagellate proportion appeared to decrease with temperatures above a threshold of 15.5°C. Although nutrient inputs and their ratios are important factors for the phytoplankton community, this study suggests that climate change and overfishing could be equally important.  相似文献   
3.
The performance of one pilot‐scale and two full‐scale membrane bioreactors (MBR) were evaluated based on the control of main operational parameters, composition of microbial community and pathogens concentration in the treated outlet. Plants were designed for 0.75 m3/day (A), 60 m3/day (B) and 30 m3/day (C). Inlet and outlet samples were monitored for chemical oxygen demand (COD), biological oxygen demand, total suspended solids, ammonia nitrogen concentration (NH4–N), nitrate nitrogen concentration, total Kjeldahl nitrogen, total phosphorus and phosphate phosphorus concentration concentrations. Plants showed good COD removal: 91.9% for Plant A, 97.8% for Plant B and 94.2% for Plant C. The targeted nitrogenous ion was NH4–N due to the requirements for outlet limits. NH4–N removal was moderate for Plant A (73.3%) and Plant B (86.1%) and excellent for Plant C (>99%). Excellent phosphorus removal was achieved by Plant A (average outlet concentration was 0.7 mg/L, efficiency 84.7%). Unsatisfactory results for phosphorus removal were achieved at the full‐scale plants due to operational problems. The dependency between the extracellular polymeric substances increase and decreasing mixed liquor volatile suspended solids for both lab and full‐scale plants was confirmed. Soluble microbial product concentrations were reduced by 65–68% after coagulant dosage for Plant A. Outlets from the MBR plants were monitored for the presence of pathogens (thermotolerant coliforms, Escherichia coli, intestinal Enterococci and culturable microorganisms at 22 and 37°C). The treated effluent from Plant A, B and C met Czech national legislation regarding reuse criteria (standards) for environment, irrigation and swimming purposes. Plants B and C were not able to achieve requirements for potable water and personal hygiene quality standards.  相似文献   
4.
The 50% and 90% P-wave detection thresholds of 3 Austrian, 2 Czech, 5 German, 1 Hungarian and 3 Slovak seismic stations have been determined for four intervals of epicentral distances by a direct method using the maximum-likelihood technique. The USGS-NEIC Earthquake Data Reports covering the period from January 1990 to November 1994 were used as the reference system. The seismic stations Kaperské Hory (KHC, Czech Republic) and Collmberg (CLL, Germany) are the stations with the best detection capabilities for all investigated intervals of epicentral distances.  相似文献   
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There is an increasing understanding and requirement to take into account the effects of invasive alien species (IAS) in environmental quality assessments. While IAS are listed amongst the most important factors threatening marine biodiversity, information on their impacts remains unquantified, especially for phytoplankton species. This study attempts to assess the impacts of invasive alien phytoplankton in the Baltic Sea during 1980-2008. A bioinvasion impact assessment method (BPL - biopollution level index) was applied to phytoplankton monitoring data collected from eleven sub-regions of the Baltic Sea. BPL takes into account abundance and distribution range of an alien species and the magnitude of the impact on native communities, habitats and ecosystem functioning. Of the 12 alien/cryptogenic phytoplankton species recorded in the Baltic Sea only one (the dinoflagellate Prorocentrum minimum) was categorized as an IAS, causing a recognizable environmental effect.  相似文献   
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