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81.
Urban sprawl is a major driving force of land use change. To develop strategies for sustainable urban development, planners need suitable indicators, one of which is the quality and quantity of green spaces in a city. To implement conservation strategies for urban areas, an assessment of how people perceive green spaces is required. The aim of this paper is to analyze: (1) willingness to contribute financially to two types of urban green spaces, (2) how people's attitudinal and socio-economic characteristics affect this willingness, and (3) to what extent this willingness is affected by the information that green spaces are important for avifauna conservation. We found that 72% of the respondents in Montpellier, France preferred natural (versus ornamental) green spaces and wanted them to be increased in the city. To achieve this, 52% of the respondents were willing to pay a percentage of their monthly household income. Giving information about birds to residents increased their preferences (especially for those having a “favourable” attitude for urban fauna) for “natural” green spaces and increased willingness to pay for green spaces among people using green spaces at least monthly. For people less concerned about nature, there was no such effect of providing bird information on preferences for green spaces. 相似文献
82.
The growth of farmed cod fed to satiation under natural conditions in the sea in North Norway (67°N) was followed over 1 year. At the start of the experiment in September 2003, the average weight was 1300 g. After 1 year, in September 2004, the average weight was 2800 g. From the end of November to June, the fish matured and spawned and there was little or no weight gain in the fish during this time. The male cod developed gonads earlier than the females. In February, the male gonad index was 19% and decreased to 7% by the end of April, whereas the female gonad index increased from 14% in February to 25% in April. The male liver index decreased by 2% in February and by another 3% in April, when it only decreased by 1% in the female cod. The muscle protein in the female cod was reduced by more than 20 g kg?1 in April, and the difference between the muscle protein in the male and the female cod was still significant in September. No differences were found in the post‐rigour muscle pH due to the sex of the fish. 相似文献
83.
The acute tolerance of juvenile Florida pompano Trachinotus carolinus L. (mean weight±SE=8.1±0.5 g) to environmental unionized ammonia‐nitrogen (NH3‐N) and nitrite‐nitrogen (NO2‐N) at various salinities was determined via a series of static exposure trials. Median‐lethal concentrations (LC50 values) of NH3‐N and NO2‐N at 24, 48, and 96 h of exposure were calculated at salinities of 6.3, 12.5 and 25.0 g L?1 at 28 °C (pH=8.23–8.36). Tolerance of pompano to acute NH3‐N exposure was not affected by salinity, with 24, 48 and 96 h LC50 values ranging from 1.05 to 1.12, 1.00 to 1.08 and 0.95 to 1.01 mg NH3‐N L?1 respectively. Regarding NO2‐N, tolerance of pompano to this environmental toxicant was compromised at reduced salinities. Median‐lethal concentrations of NO2‐N to pompano at 24, 48 and 96 h of exposure ranged from 67.4 to 220.1, 56.9 to 140.7 and 16.7 to 34.2 mg NO2‐N L?1 respectively. The results of this study indicate that juvenile Florida pompano are relatively sensitive to acute NH3‐N and NO2‐N exposure, and in the case of the latter, especially at lower salinities. 相似文献
84.
The objective of this study was to provide fundamental data for a subsequent selection of willow growth and soil remediation promoting bacterial strains. The rhizosphere of willows (Salix viminalis) was screened for cultivable bacteria with high enzymatic activity (proteolytic, pectolytic, cellulolytic, amylolytic) and production of siderophores at four test sites with broad spectrum of anthropogenic soil disturbance: sewage‐sludge application, impoverishment by unfavorable arable use, ash dumping, and household‐waste depositing. The density of bacteria in the rhizosphere ranged from 7.92 to 8.56 log10 of colony‐forming units per gram dry weight of soil and varied in a site‐ and willow‐clone‐specific manner. Within the 240 bacterial strains, a high diversity of metabolic activities was observed but was rarely combined in one strain (1.2% having six and 5.8% having five out of seven metabolic activities, respectively). The majority of strains (79.2%) revealed just one or two metabolic activities. Most common was a combination of lipolytic, proteolytic activities, and siderophore production as found in 13.8% of the bacterial strains. The 50 strains with the highest metabolic activity belonged predominantly to the Gammaproteobacteria (66%), the others to Flavobacteria (18%), Betaproteobacteria (8%), Actinobacteria (4%), and Bacilli (4%). The highest portion of cultivable strains of rhizosphere bacteria with high metabolic activities belonged to the genera Pseudomonas, Serratia, and Flavobacterium. We hypothesize that these genera include strains that support willow growth and soil remediation. Therefore, the described strain collection from the rhizosphere of S. viminalis provides a valuable basis for a subsequent selection of these candidates for applications in improvement of site adaptation of plants or remediation of soils. 相似文献
85.
McKeegan KD Aléon J Bradley J Brownlee D Busemann H Butterworth A Chaussidon M Fallon S Floss C Gilmour J Gounelle M Graham G Guan Y Heck PR Hoppe P Hutcheon ID Huth J Ishii H Ito M Jacobsen SB Kearsley A Leshin LA Liu MC Lyon I Marhas K Marty B Matrajt G Meibom A Messenger S Mostefaoui S Mukhopadhyay S Nakamura-Messenger K Nittler L Palma R Pepin RO Papanastassiou DA Robert F Schlutter D Snead CJ Stadermann FJ Stroud R Tsou P Westphal A Young ED Ziegler K Zimmermann L Zinner E 《Science (New York, N.Y.)》2006,314(5806):1724-1728
Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single (17)O-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is (16)O-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion. 相似文献
86.
87.
Jens Kruse Marion Abraham Wulf Amelung Christel Baum Roland Bol Oliver Kühn Hans Lewandowski Jörg Niederberger Yvonne Oelmann Christopher Rüger Jakob Santner Meike Siebers Nina Siebers Marie Spohn Johan Vestergren Angela Vogts Peter Leinweber 《植物养料与土壤学杂志》2015,178(1):43-88
Phosphorus (P) is an indispensable element for all life on Earth and, during the past decade, concerns about the future of its global supply have stimulated much research on soil P and method development. This review provides an overview of advanced state‐of‐the‐art methods currently used in soil P research. These involve bulk and spatially resolved spectroscopic and spectrometric P speciation methods (1 and 2D NMR, IR, Raman, Q‐TOF MS/MS, high resolution‐MS, NanoSIMS, XRF, XPS, (µ)XAS) as well as methods for assessing soil P reactions (sorption isotherms, quantum‐chemical modeling, microbial biomass P, enzymes activity, DGT, 33P isotopic exchange, 18O isotope ratios). Required experimental set‐ups and the potentials and limitations of individual methods present a guide for the selection of most suitable methods or combinations. 相似文献
88.
Development of a seven-target multiplex PCR for the simultaneous detection of transgenic soybean and maize in feeds and foods 总被引:16,自引:0,他引:16
Germini A Zanetti A Salati C Rossi S Forré C Schmid S Marchelli R Fogher C 《Journal of agricultural and food chemistry》2004,52(11):3275-3280
The detection of genetically modified organisms (GMOs) in food and feed is an important issue for all the subjects involved in raw material control, food industry, and distribution. Because the number of GMOs authorized in the EU increased during the past few years, there is a need for methods that allow a rapid screening of products. In this paper, we propose a method for the simultaneous detection of four transgenic maize (MON810, Bt11, Bt 176, and GA21) and one transgenic soybean (Roundup Ready), which allows routine control analyses to be sped up. DNA was extracted either from maize and soybean seeds and leaves or reference materials, and the recombinant DNA target sequences were detected with 7 primer pairs, accurately designed to be highly specific for each investigated transgene. Cross and negative controls were performed to ensure the specificity of each primer pair. The method was validated on an interlaboratory ring test and good analytical parameters were obtained (LOD = 0.25%, Repeatability, (r) = 1; Reproducibility, (R) = 0.9). The method was then applied to a model biscuit made of transgenic materials baked for the purpose and to real samples such as feed and foodstuffs. On account of the high recognition specificity and the good detection limits, this multiplex PCR represents a fast and reliable screening method directly applicable in all the laboratories involved in raw material and food control. 相似文献
89.
Willard C. Losinger Lindsey P. Garber Marty A. Smith H. Scott Hurd LeRoy G. Biehl Paula J. Fedorka-Cray Lee Ann Thomas Kathy Ferris 《Preventive veterinary medicine》1997,31(3-4):231-244
In a convenience sample of 100 feedlot operations (included in the United States Department of Agriculture: Animal and Plant Health Inspection Service 1994 Cattle on Feed Evaluation), up to 25 cattle fecal samples were collected and tested for the presence of Salmonella from each of two pens (the pen which contained the most-recent arrivals, and the pen with cattle that had been on feed the longest). One or more Salmonella spp. were recovered from 38 (38.0%) of the 100 feedlots, 52 (26.0%) of the 200 pens and 273 (5.5%) of the 4977 fecal samples collected. Multivariable logistic regression indicated that feeding tallow and feeding whole cottonseed or cottonseed hulls within seven days prior to fecal sample collection was associated with an increased risk of finding Salmonella in a pen. Variables not found to be significantly associated with the detection of Salmonella in a pen included region, operation size, use of sprinklers, time on feed, type of cattle in the pen, number and concentration of cattle in a pen, feeding probiotics, and various other feeds. 相似文献
90.