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941.
Carlo Alvaro 《Journal of Agricultural and Environmental Ethics》2017,30(6):765-781
Many moral philosophers have criticized intensive animal farming because it can be harmful to the environment, it causes pain and misery to a large number of animals, and furthermore eating meat and animal-based products can be unhealthful. The issue of industrially farmed animals has become one of the most pressing ethical questions of our time. On the one hand, utilitarians have argued that we should become vegetarians or vegans because the practices of raising animals for food are immoral since they minimize the overall happiness. Deontologists, on the other hand, have argued that the practices of raising animals for food are immoral because animals have certain rights and we have duties toward them. Some virtue ethicists remain unconvinced of deontic and consequentialist arguments against the exploitation of animals and suggest that a virtue-based approach is better equipped to show what is immoral about raising and using animals for food, and what is virtuous about ethical veganism. 相似文献
942.
Sotiria Anastasiou Georgios K. Sylaios Vassilios A. Tsihrintzis 《Environmental monitoring and assessment》2015,187(6):392
The present study investigates the use of combined methods of optical and acoustic sensors, in collaboration with direct in situ measurements, for the calibration and validation of a model transforming acoustic backscatter intensity series into suspended particulate matter (SPM) concentration datasets. The model follows previously elaborated techniques, placing particular attention to the parameterization of the acoustic absorption index as a function of water physical properties. Results were obtained from the annual deployment (during 2007–2008) of an upward-facing acoustic Doppler current profiler (ADCP) (307 kHz), equipped with a Wave Array, and an optical backscatter sensor (OBS), at the bottom of Thassos Passage near Nestos River plume (Thracian Sea, Northern Greece). The OBS was calibrated through linear regression, using 2007 and 2012 field sampling data, exhibiting an error of 13–14 % due to chlorophyll presence. The ADCP signal was calibrated through simultaneous measurements of backscatter intensity and turbidity profiles. Harmonic analysis on the model-produced SPM concentrations explained the tidal influence on their variability, especially during the summer. Empirical orthogonal functions analysis revealed the impact of waves and wave-induced currents on SPM variability. Finally, Nestos River sediment load was found uncorrelated to the SPM change in Thassos Passage, due to the dispersal and sediment deposition near the river mouth. 相似文献
943.
Jiangnan Tian Ayobami Matthew Olajuyin Tingzhen Mu Maohua Yang Jianmin Xing 《Environmental science and pollution research international》2016,23(12):11574-11583
The electro-Fenton (EF) process treatment of 0.1-M (rhodamine B) RhB solution was studied with different graphite cathode materials, and graphite felt (GF) was selected as a promising material in further investigation. Then, the degradation performances of gas diffusion electrode (GDE) and graphite felt (GF) were compared, and GDE was confirmed to be more efficient in RhB removal. The operational parameters such as Fe2+ dosage and current density were optimized, and comparison among different modified methods—polytetrafluoroethylene-carbon black (PTFE-CB), polytetrafluoroethylene-carbon nanotube (PTFE-CNT), electrodeposition-CB, and electrodeposition-CNT—showed 98.49 % RhB removal by PTFE-CB-modified cathode in 0.05 M Na2SO4 at a current density of 50 A/m2 and an air flow rate of 1 L/min after 20 min. Meanwhile, after cathode modified by PTFE-CB, the mineralization efficiency and mineralization current efficiency performed absolutely better than the pristine one. Cyclic voltammograms, SEM images, contact angles, and BET surface area were carried out to demonstrate stronger current responses and higher hydrophilicity of GF after modified. The value of biochemical oxygen demand/chemical oxygen demand (BOD5/COD) increased from 0.049 to 0.331 after 90-min treatment, suggesting the solution was biodegradable, and the modified cathode was confirmed to be stable after ten circle runs. Finally, a proposed degradation pathway of RhB was put forward. 相似文献
944.
Daniel T. Blumstein Louise Cooley Jamie Winternitz Janice C. Daniel 《Behavioral ecology and sociobiology》2008,62(3):457-468
We conducted four experiments to determine whether yellow-bellied marmots, Marmota flaviventris, discriminate among predator vocalizations, and if so, whether the recognition mechanism is learned or experience-independent.
First, we broadcast to marmots the social sounds of coyotes, Canis latrans, wolves, Canis lupus, and golden eagles, Aquila chrysaetos, as well as conspecific alarm calls. Coyotes and eagles are extant predators at our study site, while wolves have been absent
since the mid-1930s. In three follow-up experiments, we reversed the eagle call and presented marmots with forward and reverse
calls to control for response to general properties of call structure rather than those specifically associated with eagles,
we tested for novelty by comparing responses to familiar and unfamiliar birds, and we tested for the duration of predator
sounds by comparing a wolf howl (that was much longer than the coyote in the first experiment) with a long coyote howl of
equal duration to the original wolf. Marmots suppressed foraging and increased looking most after presentation of the conspecific
alarm call and least after that of the coyote in the first experiment, with moderate responses to wolf and eagle calls. Marmots
responded more to the forward eagle call than the reverse call, a finding consistent with a recognition template. Marmots
did not differentiate vocalizations from the novel and familiar birds, suggesting that novelty itself did not explain our
results. Furthermore, marmots did not differentiate between a wolf howl and a coyote howl of equal duration, suggesting that
the duration of the vocalizations played a role in the marmots’ response. Our results show that marmots may respond to predators
based solely on acoustic stimuli. The response to currently novel wolf calls suggests that they have an experience-independent
ability to identify certain predators acoustically. Marmots’ response to predator vocalizations is not unexpected because
25 of 30 species in which acoustic predator discrimination has been studied have a demonstrated ability to respond selectively
to cues from their predators. 相似文献
945.
Geochemical disturbance of soil cover in the nonferrous mining centers of the Selenga River basin 总被引:1,自引:0,他引:1
The anthropogenic geochemical transformation of soil cover in large nonferrous mining centers of the Selenga River basin was assessed. The results of the geochemical survey of 2010–2012 revealed the spatial distribution patterns and abundances of 18 hazardous heavy metals and metalloids in the soils of Erdenet (Mongolia) and Zakamensk (Buryat republic, Russian Federation). In both cities, mining activities disturbed soil cover which accumulates Mo, Cu, As, Sb, W in Erdenet and Bi, W, Cd, Be, Pb, Mo, Sb in Zakamensk. Maximum accumulation of elements in Erdenet is restricted to the industrial zone. In Zakamensk, it has spread on ½ of the territory with the degree of multielemental pollution exceeding the extremely dangerous level by 16 times. The effect of mining centers on the state of the river system is local and does not spread to the Selenga River. Downstream from Erdenet, an artificial pool intercepts heavy metal and metalloid flows of the Erdenetii-Gol River. By contrast, downstream from the tailing dumps of the Dzhida tungsten–molybdenum plant the concentrations of ore elements W and Mo and their accessories Bi and Cd in the Modonkul River exceed background values by 146, 20, 57, and 21 times, respectively, decreasing by an order of magnitude 30 km downstream. 相似文献
946.
Mangroves are important economically and ecologically, however mangrove cover has declined dramatically leading to habitat fragmentation and biodiversity loss. Information on mangrove cover change, fragmentation and impacts on fish diversity is poorly understood. The aims of this study are to detect spatiotemporal changes and mangrove status, examine fragmentation changes and associated effects on fish diversity. Landsat images in1989, 2000, and 2013 were used to classify mangrove cover in Ca Mau Province (Vietnam) and validated against high resolution Pleiades imagery. Fragmentation changes in mangrove cover were examined using series of landscape metrics evaluated against fish diversity indices (Simpson’s index, Jaccard’s coefficient and relative abundance). Results show that mangrove cover has declined 24.6% in the province. Currently, high and moderately dense mangroves distribute in southern half of the region while the low density mangroves occurs in the northern half. Over the 24 year study periods, the number of patches and edge density has increased 58% and 53.9%, respectively, while the mean patch size and mean patch edge has decreased 52.3% and 26.6%. Fish diversity in the more highly fragmented mangrove area was 1.78 times lower than the less fragmented mangrove. The study illustrates the applicability of using Landsat satellite imagery for use in mangrove fragmentation studies as well as the impact of fragmentation. 相似文献
947.
Chang Liu Jianlin Luo Xiaona Li Qiang Gao Jianzhang Li 《Journal of Polymers and the Environment》2018,26(1):158-165
The effects of three compounded curing agents on the properties and performance of the urea-formaldehyde (UF) resin were investigated in this study. The compounded curing agents were prepared by mixing ammonium chloride with hexamethylenetetramine, citric acid, and oxalic acid respectively at a ratio of 1:1, named N-H, N–CA, and N–OA, respectively. The curing process, crystallinity, and physical properties were measured, and the three-ply plywood was fabricated to measure its prepress strength, wet shear strength, and formaldehyde emission. Results showed that the compounded curing agents N–CA and N–OA enhanced the initial viscosity, crosslinking density and thermal stability of UF resin. Additionally, the prepress strength of the plywood bonded by UF resin with N–CA and N–OA increased by 82 and 111% respectively compared to the UF resin with NH4Cl, and the wet shear strength increased by 14 and 16%, the formaldehyde emission decreased by 19 and 42% respectively. However, owing to the short pot-life of these curing agent limited their storage time, the curing agents N–CA and N–OA should be applied to fabricate plywood in winter for obtaining a better bond strength and a lower formaldehyde emission. While the UF resin with N–HT showed a suitable pot-life, so it could be applied to fabricate plywood in summer for long time storage and avoiding procuring problem. 相似文献
948.
Yuling Zhang Hanxiao Wei Yijian Jiang Shaoxin Kang Zhiguang Hu Jilong Wang 《Journal of Polymers and the Environment》2018,26(1):116-121
Poly(aspartic acid-itaconic acid) copolymers (PAI) is a new scale inhibitor for water treatment. Thus, it is necessary to investigate its biodegradability. The biodegradability of PAI was investigated through CO2 evolution tests under different conditions based on determination of carbon dioxide production. The investigation results showed that the degradation rate of PAI on day 10 and day 28 were respectively 38.7 and 79.5%, indicating that PAI was one kind of easily biodegradable scale inhibitors. With the increase in the content of itaconic acid in copolymerization process, the biodegradability of PAI was significantly reduced. In addition, the high biodegradability might be attributed to the existence of C–N bone-structure and more –COO–. Finally, Cu2+ could decrease the degradation percentage and the enzyme inhibition effect of Cu2+ was not the linear effect, but the “low-dosage effect”. 相似文献
949.
Silvina Vargas Gil Analia Becker Claudio Oddino Mónica Zuza Adriana Marinelli Guillermo March 《Environmental management》2009,44(2):378-386
Soil microbial populations can fluctuate in response to environmental changes and, therefore, are often used as biological
indicators of soil quality. Soil chemical and physical parameters can also be used as indicators because they can vary in
response to different management strategies. A long-term field trial was conducted to study the effects of different tillage
systems (NT: no tillage, DH: disc harrow, and MP: moldboard plough), P fertilization (diammonium phosphate), and cattle grazing
(in terms of crop residue consumption) in maize (Zea mays L.), sunflower (Heliantus annuus L.), and soybean (Glycine max L.) on soil biological, chemical, and physical parameters. The field trial was conducted for four crop years (2000/2001,
2001/2002, 2002/2003, and 2003/2004). Soil populations of Actinomycetes, Trichoderma spp., and Gliocladium spp. were 49% higher under conservation tillage systems, in soil amended with diammonium phosphate (DAP) and not previously
grazed. Management practices also influenced soil chemical parameters, especially organic matter content and total N, which
were 10% and 55% higher under NT than under MP. Aggregate stability was 61% higher in NT than in MP, 15% higher in P-fertilized
soil, and also 9% higher in not grazed strips, bulk density being 12% lower in NT systems compared with MP. DAP application
and the absence of grazing also reduced bulk density (3%). Using conservation tillage systems, fertilizing crops with DAP,
and avoiding grazing contribute to soil health preservation and enhanced crop production. 相似文献
950.
Characteristics of aerosol types during large-scale transport of air pollution over the Yellow Sea region and at Cheongwon,Korea, in 2008 总被引:1,自引:0,他引:1
Episodes of large-scale transport of airborne dust and anthropogenic pollutant particles from different sources in the East
Asian continent in 2008 were identified by National Oceanic and Atmospheric Administration satellite RGB (red, green, and
blue)-composite images and the mass concentrations of ground level particulate matter. These particles were divided into dust,
sea salt, smoke plume, and sulfate by an aerosol classification algorithm. To analyze the aerosol size distribution during
large-scale transport of atmospheric aerosols, aerosol optical depth (AOD) and fine aerosol weighting (FW) of moderate imaging
spectroradiometer aerosol products were used over the East Asian region. Six episodes of massive airborne dust particles,
originating from sandstorms in northern China, Mongolia, and the Loess Plateau of China, were observed at Cheongwon. Classified
dust aerosol types were distributed on a large-scale over the Yellow Sea region. The average PM10 and PM2.5 ratio to the total
mass concentration TSP were 70% and 15%, respectively. However, the mass concentration of PM2.5 among TSP increased to as
high as 23% in an episode where dust traveled in by way of an industrial area in eastern China. In the other five episodes
of anthropogenic pollutant particles that flowed into the Korean Peninsula from eastern China, the anthropogenic pollutant
particles were largely detected in the form of smoke over the Yellow Sea region. The average PM10 and PM2.5 ratios to TSP
were 82% and 65%, respectively. The ratio of PM2.5 mass concentrations among TSP varied significantly depending on the origin
and pathway of the airborne dust particles. The average AOD for the large-scale transport of anthropogenic pollutant particles
in the East Asian region was measured to be 0.42 ± 0.17, which is higher in terms of the rate against atmospheric aerosols
as compared with the AOD (0.36 ± 0.13) for airborne dust particles with sandstorms. In particular, the region ranging from
eastern China, the Yellow Sea, and the Korean Peninsula to the Korea East Sea was characterized by high AOD distributions.
In the episode of anthropogenic polluted aerosols, FW averaged 0.63 ± 0.16, a value higher than that in the episode of airborne
dust particles (0.52 ± 0.13) with sandstorms, showing that fine anthropogenic pollutant particles contribute greatly to atmospheric
aerosols in East Asia. 相似文献