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31.
Kuhn Felipe Gustavo Berghahn Emilio Marder Munique Konrad Odorico Sperotto Raul Antonio Granada Camille Eichelberger 《Journal of Material Cycles and Waste Management》2021,23(2):717-726
Journal of Material Cycles and Waste Management - Hulls are considered residues from rice production, and due to its low commercial value, there is little interest in developing biotechnological... 相似文献
32.
M. A. Barakat R. I. Al-Hutailah M. H. Hashim E. Qayyum J. N. Kuhn 《Environmental science and pollution research international》2013,20(6):3751-3759
Photocatalytic process has shown recently a great potential as an environmental friendly and clean remediation technology for organic pollutants in wastewater. This work described the synthesis of silver-based bimetallic nanoparticles using colloid chemistry and the subsequent immobilization onto titania to form composite photocatalytic materials (titania-supported Ag–Pt nanoparticles). The photocatalysts were characterized by X-ray diffraction, electron microscopy, and nitrogen physisorption. The catalytic activity of the photocatalysts was evaluated by photocatalytic degradation of phenol and 2-chlorophenol (2-CP) in synthetic wastewater solutions. The photocatalytic processes were conducted in a batch photoreactor containing appropriate solutions of phenol and 2-CP with UV irradiation of 450 W. UV-visible spectrophotometer was used for analyzing the concentration of phenol and 2-CP in solutions. Parameters affecting the photocatalytic process such as the solution pH, phenol and 2-CP concentrations, and catalyst concentration were investigated. The results obtained revealed that TiO2-supported Ag/Pt nanoparticles showed a higher activity for UV-photocatalytic degradation of both phenol and 2-CP pollutants in the solution (as compared to the plain rutile TiO2). The photodegradation processes were optimized by the 0.5-g/L catalyst with a pollutant concentration of 50 mg/L for all the samples. Complete degradation for both phenol and 2-CP was achieved after 120 min. 相似文献
33.
Ballach HJ Kuhn A Wittig R 《Environmental science and pollution research international》2003,10(5):308-316
Following their exposure to anthracene, the roots of Populus nigra L. Loenen showed traces of 9 substances classed as products of biodegradation. The main substances detected were phthalic acid and 9,10-anthraquinone, followed by hydroxyanthracene and methoxyanthracene and five other compounds which could not be identified. Due to the relatively low concentration of degradation products found in the roots, further degradation to lower molecular compounds are discussed. The presence of 9,10-anthraquinone as the main product of the degradation of anthracene was also evident in the control tests with unplanted sandy substrate, although the content was higher in the planted series of tests. As a non-sterile approach was chosen, it may be assumed that a microbial degradation for 9,10-anthraquinone took place in the control series. However, it is difficult to differentiate clearly between a microbial degradation of anthracene in the substrate and metabolization in the roots due in part to the absence of specific degradation products in the various reaction areas. 相似文献
34.
35.
Werner Kuhn 《Die Naturwissenschaften》1963,50(6):171-177
36.
GVO-Pollenmonitoring zum Bt-Maisanbau im Bereich des NSG/FFH-Schutzgebietes Ruhlsdorfer Bruch 总被引:1,自引:1,他引:0
F. Hofmann R. Epp A. Kalchschmid L. Kruse U. Kuhn B. Maisch E. Müller S. Ober J. Radtke U. Schlechtriemen G. Schmidt W. Schröder W. v. d. Ohe R. Vögel N. Wedl W. Wosniok 《Environmental Sciences Europe》2008,20(4):275-289
Aim and Background Precautionary regulations for the production of genetically modified crops (Gentechnik-Pflanzenerzeugungsverordnung, GenTPflEV 2008) provide isolation distances for the cultivation of genetically modified maize – Bt-maize – in the vicinity of conventional maize cultivation (150?m) as well as of organic maize cultivation (300?m). Nature reserves are not included. The aim of this study was to investigate whether maize pollen of surrounding fields were dispersed in the Flora-Fauna-Habitat (FFH) Ruhlsdorfer Bruch. In the vicinity of the nature reserve Bt-maize species MON 810 as well as conventional maize was grown. The survey should provide appropriate isolation distances for the cultivation of Bt-maize with regard to sustainable protection of non-target-organisms (NTO) in the Ruhlsdorfer Bruch. Materials and Methods The collection of maize pollen in the Ruhlsdorfer Bruch was carried out at three sampling sites in the FFH or rather in the immediate vicinity in July and August 2007 by means of twelve technical and three biological pollen samplers. The technical samplers Sigma-2/PMF enable point sampling. They are primarily influenced by wind and topography and provide information about the effective entry, the maize pollen flow and the maize pollen deposition at the location of the sampler. Honey bees roam over longer distances and are hence planar collectors. Thus, they also provide information about the plants blooming in a distinct area. Furthermore, the biological preferences during the collection are captured, whereas a technical sampler does not perform a species dependent selection. Hence, both the technical and the biological samplers complement one another in their scope of application. The pollen samples were identified microscopically, enumerated quantitatively, and the pollen-DNA was analysed by means of the PCR-method. Results All monitoring sites at the Ruhlsdorfer Bruch revealed maize pollen entries. The pollen deposition reached values of 1.75 million maize pollen/m² in the close-up range. The monitoring sites located 120?m within the protected area still featured 99,000 maize pollen/m². As shown by the statistical analysis, at a distance of 1,000?m still 28,000 maize pollen/m² must be expected. The results of the microscopic pollen analysis of the pollen pellets proved that the bees collect maize pollen at all three sites. Although maize pollen is not the main food source the high collection efficiency of the bees resulted in large amounts of introduced pollen. The biomolecular proof of pollen-DNA in the field samples was corroborated by analogue results for both the technical and biological pollen sampling by two independent laboratories. The results of these quality controlled analyses gave unambiguous evidence that under the cultivation conditions in 2007 an entry of Bt-maize pollen into the FFH Ruhlsdorfer Bruch was existent. Discussion The maize pollen deposition at the Ruhlsdorfer Bruch corresponds with additional supra-regional investigations which were conducted over several years with the same method. However, the pollen entries into the Ruhlsdorfer Bruch are above-average. Possible reasons are the size of the maize fields (>?10?ha), the geographical collocation between maize fields and protected area (lee location, through-shaped, thermal currents) as well as weather conditions and maize bloom during the sampling period July and August 2007. A distance of 1,000?m or more is necessary to avoid maize pollen deposition of more than 100,000/m² with a probability of 90?%. Conclusions The results of this investigation prove an entry of Bt-maize pollen into the FFH under the cultivation and weather conditions in summer 2007. According to the results of this and related studies and considering precautionary principle and the effect terms defined in the Federal Immission Protection Law, it becomes clear that reasonable isolation distances between Bt-maize fields and protected areas have to be introduced in order to minimise the entry of GM-maize pollen and to prevent adverse effects on protected NTOs. Recommendations Due to the fact that no toxicological investigations are available for the butterflies occurring in the FFH, highest protection standards should be implemented to avoid Bt-maize pollen entries into the Ruhlsdorfer Bruch. That implies that highest possible isolation distances for Bt-maize cultivation have to be considered, but at least a distance of 1,000?m is recommended. Following this a maize pollen deposition of more than 100,000 maize pollen/m² should be pevented with a certainty of 90?% as well as an exceeding exposure of foraging insects. Outlook By means of the pollen monitoring it becomes possible to survey empirically defined limits of pollen exposure. This should be performed in the nature reserve area at sites of expected maximum exposure, e.?g. at the boundaries of the FFH towards the maize fields and at exposed sites. 相似文献
37.
Developing a Monitoring Protocol for Visitor-Created Informal Trails in Yosemite National Park,USA 总被引:1,自引:0,他引:1
Informal trails created or perpetuated by visitors is a management challenge in many protected natural areas such as Yosemite
National Park. This is a significant issue as informal trail networks penetrate and proliferate into protected landscapes
and habitats, threatening ecological integrity, aesthetics, and visitor experiences. In order to develop effective strategies
for addressing this problem under an adaptive management framework, indicators must be developed and monitoring protocol must
be established to gather timely and relevant data about the condition, extent, and distribution of these undesired trail segments.
This article illustrates a process of developing and evaluating informal trail indicators for meadows in Yosemite Valley.
Indicator measures developed in past research were reviewed to identify their appropriateness for the current application.
Information gaps in existing indicator measures were addressed by creating two new indices to quantify the degree of informal
trailing based on its land fragmentation effects. The selected indicator measures were applied to monitoring data collected
between 2006 and 2008. The selected measures and indices were evaluated for their ability to characterize informal trail impacts
at site and landscape scales. Results demonstrate the utility of indicator measures in capturing different characteristics
of the informal trail problem, though several metrics are strongly related to each other. The two fragmentation indices were
able to depict fragmentation without being too sensitive to changes in one constituent parameter. This study points to the
need for a multiparameter approach to informal trail monitoring and integration with other monitoring data. Implications for
monitoring programs and research are discussed. 相似文献
38.
39.
Coastal protection strategies increasingly have to take into account the effects of climate change. At present, engineering and natural science models that assess the impact of global climatic transformations on regional coastal zones and their protection structures remain rather detached from the knowledge and insights of regional practitioners. The main thesis of this contribution, using a case study from the North Sea Coast of Germany, is that innovative coastal protection requires not only interdisciplinary research but transdisciplinary collaboration in order to develop a viable adaptation strategy. The investigation of the social dimension of climate change and coastal protection strategies, using qualitative interviews with organized regional stakeholders, climate researchers and coastal engineers, as well as a representative public survey, contributes to a comprehensive understanding of regional perceptions with respect to climate change and coastal protection. 相似文献
40.