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61.
In order to assess whether nitrogen (N) loads in mosses reflect different land uses, 143 sites in North Rhine-Westphalia, the Weser-Ems Region and the Euro Region Nissa were sampled between 2000 and 2005. The data were analysed statistically with available surface information on land use and forest conditions. N bioaccumulation in mosses in the Weser-Ems Region with high densities of agricultural land use and livestock exceeded the concentrations in the more industrialised Euro Region Nissa. In all three study areas agricultural and livestock spatial densities were found to be positively correlated with N bioaccumulation in mosses. In North Rhine-Westphalia, the N concentrations in mosses was also moderately correlated with N concentrations in leaves and needles of forest trees. The moss method proved useful to assess the spatial patterns of N bioaccumulation due to land use.  相似文献   
62.
Ecoregionalizations are important for the evaluation of monitoring networks. In this article a method is decribed concerning how to define Germany’s ecoregions by using ecological data on soil, vegetation, climate and elevation through the aid of classification and regression trees. The resulting ecoregions can be linked to metadata (parameters, methods, quality control and assurance measures) from thousands of Germany’s environmental monitoring sites. Together with GIS procedures, multivariate statistics and geostatistics, ecoregions are useful for integrating data of environmental measurements according to ecological and spatial criteria.  相似文献   
63.
Ausblick     

Beitragsserien 2008

Ausblick  相似文献   
64.
This study aimed at statistically investigating the association between the internal exposure of children and young adults to uranium (U) and epidemiologically relevant external determinants of exposure. The investigation was performed with data from two studies within the framework of the German health-related environmental monitoring program: The German Environmental Survey for Children (GerES IV) conducted by the Federal Environment Agency (Umweltbundesamt) with data on 1,780 children 3–14 years of age and their home environment and the German Environmental Specimen Bank (ESB, section: human specimens) with data on 2,253 students 20–29 years of age. Both studies provided data on the U levels in human urine for all probands. GerES IV furthermore provided an extensive environmental and demographic database on, e.g., U levels in drinking water. The data from GerES IV and ESB were linked by GIS to spatially relevant exposure information, including background values of U in stream sediments and in upper and lower soils, U levels in mosses and particulate matter in the lower atmosphere, precipitation and elevation as well as forest density. Bivariate correlation analysis and two decision tree models showed moderate but significant associations between U in human urine and U levels in drinking water, stream sediments and upper and lower soils. Future investigations considering additional epidemiologically relevant data sets may differentiate the results. Furthermore, the sample design of future environmental epidemiology studies should take the spatial evaluation of the data into greater account.  相似文献   
65.
Trace elements and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in soils from rural and light-industrialized sites (n=168) of Province of Pavia (Northern Italy). Most of the trace element values fit in typical ranges of concentrations in soils and are similar to the ones reported for rural sites in Italy or sites with no direct anthropogenic impact. Total concentrations of 2,3,7,8 chlorine substituted PCDD/Fs in superficial soils ranged between 24.4 and 1287 pg g(-1) dw (0.5-28.9 pg WHO(98)-TEQ g(-1) dw). The North Eastern part of the Province presented significantly higher levels (p<0.001) than the rest of the Province for As, Cd, Hg, Pb, Zn and PCDD/Fs. While the existence of a defined heavy metal polluting source for this specific site has been suggested, in the case of PCDD/Fs, profiles were not linked to any specific emission source fingerprint. In the whole extension of Pavia Province, OCDD/F dominated the 2,3,7,8 chlorine substituted congener soil pattern, followed by the 1,2,3,4,6,7,8 hepta-CDD/F congener. Principal Component Analysis (PCA) showed that this profile could not be associated to any described PCDD/F emission source fingerprint and was relatively similar to the baseline deposition of sites with no direct impact of PCDD/F emission sources independently of land use.  相似文献   
66.

Purpose  

Climate warming can change the geographic distribution and intensity of the transmission of vector-borne diseases such as malaria. The transmitted parasites usually benefit from increased temperatures as both their reproduction and development are accelerated. Lower Saxony (northwestern Germany) has been a malaria region until the 1950s, and the vector species are still present throughout Germany. This gave reason to investigate whether a new autochthonous transmission could take place if the malaria pathogen was introduced again in Germany.  相似文献   
67.
Background, Aim, and Scope The introduction of genetically modified plants (GMP) into the European agriculture primarily has been investigated in respect of economical aspects, its impacts on conventional crops, and direct or indirect effects on human health. Potential ecological impacts, especially their long term and large scale implications, were out of focus, usually. A special task is to protect the integrity of nature reserves. According to §?23 of the German Nature Protection Law (BNatSchG) nature reserves are to protect nature and landscape properties by preserving and developing existing as well as by re-establishing biotopes of wild and endangered species. According to §?34a of the BNatSchG the use of GMP has to be accompanied by an environmental impact analysis of possible risks like it has to be done in projects affecting the integrity of Flora-Fauna-Habitats (FFH) or European bird sanctuaries. Considering this, the joint research project “Recommendations for isolation distances concerning the cultivation of genetically modified plants in the neighbourhood of protected areas” which was promoted by the Federal Agency for Nature Conservation (BfN) aimed at describing possible risks for biocoenoses in conservation areas that could be caused by the cultivation of GMP in their vicinity and at evaluating measures which could mitigate or hinder negative effects. The article at hand concentrates on describing the implications which would emerge when introducing different isolation distances concerning the cultivation of herbicide resistant oil seed rape (HR-OSR) and insect resistant maize (B.?t.-maize) near protection areas. On the other hand, a methodology is introduced which was developed to classify the German nature reserves according to their potential endangerment by GMP cultivation and to minimise calculation efforts for modelling possible impacts. Materials and Methods In 2003, there were around 7,400 nature reserves which covered 3?% of the whole territory of Germany. A geographical information system (GIS) was used to integrate geometries of conservation areas, land use data (CORINE landcover), agricultural information on district level as well as a map of German ecoregions. At first, it was evaluated how much arable land for B.?t.-maize or HR-OSR cultivation would remain if introducing different isolation distances around nature reserves (NSG). Furthermore, the NSG were aggregated to several homogenous classes reflecting different levels of cultivation intensities in their vicinity and different geometric properties. This was realised calculating a geometric coefficient (GC) which describes the ratio of periphery and area of each NSG in order to abstract the risk of GMP invasion. The density of maize and rape cropping near the NSG was expressed by a cultivation coefficient (CC). According to regional agricultural surveys, this was calculated by adding up the area of maize and rape fields within a radius of 1,000?m (maize) and 4,000?m (rape), respectively, around the NSG. Results Considering an isolation distance of 1,000?m around the NSG, 90?% of the farmland in Germany would be available for GMP cultivation. 50?% would remain when establishing an isolation distance of 4,000 m. The combination of GC and CC resulted in a total of nine risk categories (RC) describing the potential risk of endangerment by GMP cultivation in the vicinity of NSG. Areas with highest risk were grouped in RC nine where the smallest NSG (+ GC) in the main cultivation areas of maize or corn (+ CC) were summarised. With a numerical proportion of 7?% those sites cover only 0.4?% of total area of all NSG. All nature reserves showing highest CC values had a total proportion of 60?%. Discussion The derivation of GC and CC was based on a hierarchical approach and was implemented by complex GIS procedures. This makes it easy to calculate additional values for different GMP, protection areas or isolation distances. The RC were useful for choosing representative modelling sites in order to minimise calculation efforts when modelling possible impacts of GMP cultivation in vicinity of nature reserves. Conclusions The assessment of isolation distances around protection areas should be performed for each area individually concerning the GMP specific effects and dispersal properties as well as the protected organisms and the main protection targets. Especially HR-OSR is critical because of its volunteers and hybridisation partners. Another main source of GMP dispersal into protection areas might be the contamination of conventional seeds with transgene OSR seeds. Recommendations and perspectives Before defining and applying particular measures in order to protect conservation areas from possible impacts due to GMP cultivation a political and societal discussion is necessary in order to assess which GMP induced impacts may be tolerated. This has to be supported by additional scientific studies based on empirical and estimated data evaluating possible dispersal distances of GM pollen and possible environmental impacts of released transgenes and their toxins. According to the EU Directive 2001/18/EC the cultivation of GMP should be accompanied by a case-specific monitoring and general surveillance, as well. It should be realised as soon as possible, since the release and the cultivation of GMP in Germany have been started, already. The monitoring should be complemented by the implementation of a web-based geoinformation system (WebGIS) which enables the compilation and evaluation of the data and relevant geodata.  相似文献   
68.
69.
The degradation of ammonium by free and immobilized bacteria in different reactor systems was investigated. It was found that the start-up of a nitrifying system is enhanced if a reservoir of immobilized bacteria is present. It was also found that in a single stage system with suspended nitrifying bacteria a stable ammonium removal > 95 % could be established up to an influent ammonium concentration of 1000 mg/1 and a volumetric loading rate (VLR) of 2.3 kg NH4+ m−3 d−1. The oxygen uptake rate (OUR) due to nitrification processes was greatly enhanced with increasing volumetric loading rates. Using nitrifying bacteria immobilized on Siran material it was demonstrated that the ammonium degradation rate was directly proportional to the initial ammonium concentration.  相似文献   
70.
Integrative (interdisciplinary and transdisciplinary) landscape research projects are becoming increasingly common. As a result, researchers are spending a larger proportion of their professional careers doing integrative work, participating in shifting interdisciplinary teams, and cooperating directly with non-academic participants. Despite the growing importance of integrative research, few studies have investigated researchers’ experiences in these projects. How do researchers perceive the outcomes of integrative projects, or career effects? Do they view the projects generally as successes or failures? This study analyses researchers’ experiences in integrative landscape studies and investigates what factors shape these experiences. The data stems from 19 semi-structured qualitative interviews and a Web-based survey among 207 participants in integrative landscape research projects. It finds that researchers experience participation in integrative projects as positive, in particular discussions among participants, networking, teamwork, and gaining new insights and skills. Furthermore, most researchers perceive the projects as successful and as having a positive effect on their careers. Less positive aspects of integration relate to publications and merit points. Factors found to contribute to positive experiences include reaching a high degree of integration amongst the involved disciplines, common definitions of integrative research concepts, and projects that include a large share of fundamental research as well as projects with many project outcomes. Based on these findings, we advise future projects to plan for integration, facilitate discussions, and reach agreement on integrative concepts. We suggest that aspects of fundamental research be included in integrative projects. We also suggest that planning be done at an early stage for peer-reviewed publications, to ensure that participants gain merit points from their participation in integrative research efforts.  相似文献   
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