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91.
REED F. NOSS ERICA FLEISHMAN† DOMINICK A. DELLASALA‡ JOHN M. FITZGERALD§ MART R. GROSS MARTIN B. MAIN†† FIONA NAGLE‡‡ STACEY L. O'MALLEY JON ROSALES§§ 《Conservation biology》2009,23(4):825-833
Abstract: The Society for Conservation Biology (SCB) can enhance conservation of biodiversity in North America by increasing its engagement in public policy. Toward this end, the North America Section of SCB is establishing partnerships with other professional organizations in order to speak more powerfully to decision makers and taking other actions—such as increasing interaction with chapters—geared to engage members more substantively in science-policy issues. Additionally, the section is developing a North American Biodiversity Blueprint, which spans the continental United States and Canada and is informed by natural and social science. This blueprint is intended to clarify the policy challenges for protecting continental biodiversity, to foster bilateral collaboration to resolve common problems, and to suggest rational alternative policies and practices that are more likely than current practices to sustain North America's natural heritage. Conservation scientists and practitioners can play a key role by drawing policy makers' attention to ultimate, as well as proximate, causes of biodiversity decline and to the ecological and economic consequences of not addressing these threats. 相似文献
92.
Mahmoud Marwa M. Sanad Eman F. Hamdy Nadia M. 《Environmental science and pollution research international》2021,28(28):36984-37000
Environmental Science and Pollution Research - The discovery of microRNAs (miRNAs) 20 years ago has advocated a new era of “small molecular genetics.” About 2000 miRNAs are present that... 相似文献
93.
Abdelnour Sameh A. Yang Chun-Yan Swelum Ayman A. Abd El-Hack Mohamed E. Khafaga Asmaa F. Abdo Mohamed Shang Jiang-Hua Lu Yang-Qing 《Environmental science and pollution research international》2020,27(31):38472-38490
Environmental Science and Pollution Research - Global warming is considered as the main environmental stress affecting ecosystems as well as physiological and biochemical characteristics, and... 相似文献
94.
Vaughan G Quinn PT Green AC Bean J Roscoe HK van Roozendael M Goutail F 《Journal of environmental monitoring : JEM》2006,8(3):353-361
We present in this paper fifteen years' measurements, from March 1991 to September 2005, of stratospheric NO2 vertical columns measured by a SAOZ zenith-sky visible spectrometer. The instrument spent most of its time at Aberystwyth, Wales, with occasional excursions to other locations. The data have been analysed with the WinDOAS analysis program with low-temperature high-resolution NO2 cross-sections and fitting a slit function to each spectrum. Because of a change in detector in May 1998 there is some uncertainty about the relative changes before and after this date, which are partially constrained by the results of an intercomparison exercise. However, the effect of the Mt Pinatubo aerosol cloud is very evident in the data from 1991-94, with a decrease of 10% in NO2 in the summer of 1992 (the SAOZ was located in Lerwick, Scotland during the winter of 1991-92 and observed very low NO2 values but these cannot be directly compared to the Aberystwyth data). To focus more on interannual and long-term variations in NO2, a seasonal variation comprising an annual and semi-annual component was fitted to the morning and evening twilight separately from 1995 to the present. This fit yielded average NO2 columns of 4.08 x 10(15) cm(-2) and 2.68 x 10(15) cm(-2) for the evening and morning twilight, respectively, with a corresponding annual amplitude of +/-2.08 x 10(15) cm(-2) and +/-1.50 x 10(15) cm(-2). Departures from the fitted curve show a trend of 6% per decade, consistent with that reported elsewhere, for the period 1998-2003, but in the past two years a distinct interannual variation of amplitude of approximately 8% has emerged. 相似文献
95.
A Characterization of Selected Endocrine Disruptor Compounds in a Portuguese Wastewater Treatment Plant 总被引:1,自引:0,他引:1
Maurício R Diniz M Petrovic M Amaral L Peres I Barceló D Santana F 《Environmental monitoring and assessment》2006,118(1-3):75-87
Anthropogenic compounds that are able to disrupt the endocrine system of wildlife species are a major cause for concern and
have led to a demand for new screening methods. The identification and quantification of endocrine disruptor compounds at
wastewater treatment plant is of major interest to assess the endocrine activity of wastewater treatment plant discharges
into the environment. This study consists of a preliminary survey of concentrations of previously selected endocrine disruptor
compounds, undertaken to establish environmental concentrations and to support a biological program assay exposing freshwater
fish to them. Selected endocrine disrupting chemicals (APEs, bisphenol A and 17 β-estradiol) were measured in samples from a wastewater treatment plant located in Lisbon (Portugal), using recent commercial
enzyme-linked immunosorbent assay kits and also LC-MS/MS. The results show that the wastewater treatment plant treatment process
is efficient on the removal of target endocrine disruptor compounds. However, environmentally significant concentrations are
still present in the treated effluent. The results also show that enzyme-linked immunosorbent assay kit is suitable for routine
analysis of the selected compounds. The results are also useful since the wastewater treatment plant is located in a Mediterranean
region, which results in an effluent with its own characteristics. 相似文献
96.
A submersible sonde equipped with a specific conductivity probe, linked with a global positioning satellite receiver was developed, deployed on a small boat, and used to map spatial and temporal variations in specific conductivity in a large reservoir. 7,695 sample points were recorded during 8 sampling trips. Specific conductivity ranged from 442,uS/cm to 3,378,uS/cm over the nine-month study. The data showed five statistically different zones in the reservoir: 2 different riverine zones, 2 different riverine transition zones, and a lacustrine zone (the main lake zone). These data were imported to a geographic information system where they were spatially interpolated to generate 8 maps showing specific conductivity levels across the entire surface of the lake. The highly dynamic nature of water quality, due to the widely differing nature of the rivers that flow into the reservoir and the effect of large inflows of fresh water during winter storms is easily captured and visualized using this approach. 相似文献
97.
Abstact The present study was designed to evaluate indirect, non-invasive, on-line measurement of biofilm thickness using an electrical capacitance technique. Several assays were carried out and the results showed that, at a frequency of 1 kHz, electrical capacitance could be used to measure biofilm thickness indirectly (with a correlation coefficient of 0.9495). The reproducibility revealed by the assays was also highly satisfactory.However, in contrast to what was expected, there was an inverse relationship between electrical capacitance and biofilm thickness, i.e. electrical capacitance diminished with the increase in the biofilm thickness.The tests were also carried out at different frequencies (1 kHz, 10 kHz and 100 kHz) 相似文献
98.
Christian Mrz Felipe S. Freitas Johan C. Faust Jasmin A. Godbold Sian F. Henley Allyson C. Tessin Geoffrey D. Abbott Ruth Airs Sandra Arndt David K. A. Barnes Laura J. Grange Neil D. Gray Ian M. Head Katharine R. Hendry Robert G. Hilton Adam J. Reed Saskia Rühl Martin Solan Terri A. Souster Mark A. Stevenson Karen Tait James Ward Stephen Widdicombe 《Ambio》2022,51(2):370
Unprecedented and dramatic transformations are occurring in the Arctic in response to climate change, but academic, public, and political discourse has disproportionately focussed on the most visible and direct aspects of change, including sea ice melt, permafrost thaw, the fate of charismatic megafauna, and the expansion of fisheries. Such narratives disregard the importance of less visible and indirect processes and, in particular, miss the substantive contribution of the shelf seafloor in regulating nutrients and sequestering carbon. Here, we summarise the biogeochemical functioning of the Arctic shelf seafloor before considering how climate change and regional adjustments to human activities may alter its biogeochemical and ecological dynamics, including ecosystem function, carbon burial, or nutrient recycling. We highlight the importance of the Arctic benthic system in mitigating climatic and anthropogenic change and, with a focus on the Barents Sea, offer some observations and our perspectives on future management and policy. 相似文献
99.
By mechanical-biological treatment (MBT) of residual municipal solid waste the behaviour of landfills can be significantly improved. After MBT the organic content (COD and BOD5), total organic carbon, and total nitrogen in the leachate, as well as the gas production rate, are reduced to values lower than 90% of the fresh untreated waste. The volume of the stabilized material to be disposed on landfills decreases enormously, by up to 70%. The monitoring effort for a landfill constructed under these conditions is reduced to a minimum and the stabilized material can be used in other ways, as material for reforestation, for cover material or for thermal utilization to produce energy. Environmental conditions are important in MBT, as well as waste characteristics. This paper describes the results of a pilot project of MBT performed in Rio de Janeiro, Brazil. The results have shown that this technology can be used successfully in developing countries, with economy for the society and important results for the environment. 相似文献
100.
Influence of dairy manure addition on the biological and thermal kinetics of composting of greenhouse tomato plant residues 总被引:2,自引:0,他引:2
A laboratory-scale bioreactor was used to investigate the influence of dairy manure addition (as an inoculum and a carbon source) on the biological and thermal kinetics of the composting process of tomato plant residues-wood shavings mixture. Urea was added (as a nitrogen source) to correct the initial C:N ratio to 30:1 and the initial moisture content was also adjusted to 60%. The result of this study indicated that manure addition to the tomato residues-wood shavings mixture is a good source of macro and micronutrients required for supporting the composting microorganisms. Manure addition increased the rate of temperature increase and the duration of maximum temperature and reduced the lag and the peak time, all of which resulted in a significant reduction in the retention time. However, thermophilic temperature (> or = 40 degrees Celsius) was only achieved with 30%, 40% and 50% manure addition for 3, 7 and 9h. Total carbon reductions were in the range of 9.4-10.8% and TKN reductions were in the range of 3.4-6.0%. Neither the nitrogen nor the moisture content were limiting factors as the C:N ratio remained in the range of 26:1 to 28:1 and the moisture content remained within the optimum range of 58-61%. The maximum temperature of each mixture correlated with the reduction of total carbon, but carbon availability was a limiting factor in these experiments. In order to attain and sustain a thermophilic phase during the composting process, the addition of a readily available carbon source to the tomato should be investigated and carbon type (carbohydrates, proteins and fats) should be taken into account. 相似文献