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401.
Emma Prichard Elise F. Granek 《Environmental science and pollution research international》2016,23(22):22365-22384
Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of literature reporting the effects of PPCPs on freshwater organisms, but studies on the effects of PPCPs to marine and estuarine organisms are limited. Among effect studies, the vast majority examines subcellular or cellular effects, with far fewer studies examining organismal- and community-level effects. We reviewed the current published literature on marine and estuarine algae, invertebrates, fish, and mammals exposed to PPCPs, in order to expand upon current reviews. This paper builds on previous reviews of PPCP contamination in marine environments, filling prior literature gaps and adding consideration of ecosystem function and level of knowledge across marine habitat types. Finally, we reviewed and compiled data gaps suggested by current researchers and reviewers and propose a multi-level model to expand the focus of current PPCP research beyond laboratory studies. This model includes examination of direct ecological effects including food web and disease dynamics, biodiversity, community composition, and other ecosystem-level indicators of contaminant-driven change. 相似文献
402.
M. L. Amadori C. Del Vais P. Fermo P. Pallante 《Environmental science and pollution research international》2017,24(16):13921-13949
The aim of this study is to setup a first chemical database that could represent the starting point for a reliable classification method to discriminate between Archaic Phoenician and Punic pottery on the base of their chemical data. This database up to now can discriminate between several different areas of production and provenance and can be applied also to unknown ceramic samples of comparable age and production areas. More than 100 ceramic fragments were involved in this research, coming from various archaeological sites having a crucial importance in the context of the Phoenician and Punic settlement in central and western Mediterranean: Carthage (Tunisia), Toscanos (South Andalusia, Spain), Sulci, Monte Sirai, Othoca, Tharros (Sardinia, Italy) and Pithecusa (Campania, Italy). Since long-time archaeologists hypothesised that Mediterranean Archaic Phoenician and Punic pottery had mainly a local or just a regional diffusion, with the exception of some particular class like transport amphorae. To verify the pottery provenance, statistical analyses were carried out to define the existence of different ceramic compositional groups characterised by a local origin or imported from other sites. The existing literature data are now supplemented by new archaeometric investigations both on Archaic Phoenician ceramics and clayey raw materials from Sardinia. Therefore, diffractometric analyses, optical microscopy observations and X-ray fluorescence analyses were performed to identify the mineralogical and chemical composition of Othoca ceramics and clayey raw material. The obtained results were then compared with own literature data concerning Phoenician and Punic pottery in order to find features related to the different ceramic productions and their provenance. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were also performed on the chemical compositional data in order to discriminate ceramic groups. A very complex situation was found: imported ceramics coming from Carthage, with a large-scale distribution, were found together with a predominant local production pottery. The archaeometric results demonstrate that historical and typological approach has to be supported by scientific analyses to better understand local or Mediterranean exchanges. 相似文献
403.
Since 2005, a dramatic decline of the Arctic sea-ice extent is observed which results in an increase of shipping activities. Even though this provides commercial and social development opportunities, the resulting environmental impacts need to be investigated and monitored. In order to understand the impact of shipping in arctic areas, the method described in this paper determines the travel time, fuel consumption and resulting exhaust emissions of ships navigating in arctic waters. The investigated case studies are considering ship particulars as well as environmental conditions with special focus on ice scenarios. Travel time, fuel consumption and exhaust gas emission were investigated for three different vessels, using different passages of the Northern Sea Route (NSR) in different seasons of years 1960, 2000 and 2040. The presented results show the sensitivity of vessel performance and amount of exhaust emissions to optimize arctic traffic with respect to efficiency, safety and environmental impact. 相似文献
404.
Natija Barhoumi Nihal Oturan Salah Ammar Abdellatif Gadri Mehmet A. Oturan Enric Brillas 《Environmental Chemistry Letters》2017,15(4):689-693
There is actually increasing concern about the accumulation of antibiotics, such as tetracycline, in soil and water bodies. There is therefore a need for efficient methods to degrade antibiotics and thus clean waters. Here we tested the degradation of tetracycline using the heterogeneous electro-Fenton-pyrite method and compared the results with the conventional electro-Fenton method. The reaction was performed with a boron-doped diamond or Pt anode and carbon-felt cathode allowing electrogeneration of H2O2 from O2 reduction. Results show an increasing tetracycline mineralization using the following methods: anodic oxidation with electrogenerated H2O2, electro-Fenton and then electro-Fenton-pyrite using boron-doped diamond. Ion-exclusion HPLC revealed the complete removal of malic malonic, succinic, acetic, oxalic and oxamic acids. Nitrogen present in tetracycline was mainly mineralized in NH4 +. The higher efficiency of electro-Fenton-pyrite is explained by self-regulation of soluble Fe2+ and pH to 3.0 from pyrite catalyst favoring larger ·OH generation from Fenton’s reaction. 相似文献
405.
Jeanette M. McGuire J. D. Congdon K. T. Scribner R. D. Nagle 《Behavioral ecology and sociobiology》2014,68(10):1589-1602
Male reproductive success (RS) in polygamous species with minimal social systems is often determined by the number of mates. However, because male RS is translated through females, the number of offspring sired can also be influenced by female qualities. Empirically sufficient data to document how tradeoffs between mate number and quality influence male RS are seldom available for long-lived, iteroparous species. We combined long-term life history data (1983–2006) on the E. S. George Reserve (ESGR, MI, USA) with parentage data from 155 clutches of 59 female painted turtles (Chrysemys picta marginata) of varying reproductive frequencies (2003–2006) to determine the relative contribution of female numbers and qualities on male RS. One previously documented trait of female painted turtles that can have substantial influences on male RS is repeat paternity through the use of stored sperm to fertilize over 95 % of within-year clutches. In addition, our study found that second-clutch producing female painted turtles on the ESGR have higher among-year reproductive frequencies than do first-clutch only females. Multiple paternity was detected in 14.1 % of clutches (min-max?=?6.1–30.0 % annually), and the number of mates of both sexes was low annually (males 1.0; females 1.2) and over 4 years (males 1.1; females 1.7). Among successful males, RS varied substantially (1–32 offspring) and was strongly influenced by the combination of female reproductive frequency and repeat paternity (>38 % among years), but not mate number. Low mate number for both sexes was unexpected in a species without complex mating behaviors or parental care. 相似文献
406.
Alamgir Hossain Jamal Naser Monzur Alam Imteaz 《Environmental Modeling and Assessment》2011,16(4):359-367
This paper presents comprehensive 3D numerical investigations on depositions of particles flowing through a horizontal pipe
loop consisting of four bends. The multiphase mixture model available in FLUENT 6.2 was used in this study. In this numerical
simulation, five different particle sizes have been used as secondary phases to calculate real multiphase effect in which
inter-particle interaction has been considered. The deposition of particles along the periphery of the pipe wall was investigated
as a function of particle size and fluid velocity. The simulations showed that near the upstream of the bends, maximum particle
concentration occurred at the bottom of the pipe. However, downstream the bends, the maximum particle concentration occurred
at an angle of 60° from the bottom. The larger particles clearly showed deposition near the bottom wall except downstream.
As expected, the smaller particles showed less tendency of deposition and lesser at higher velocity. This numerical investigation
showed qualitative agreement with the experiments conducted by Commonwealth Scientific and Industrial Research Organisation,
Melbourne team for similar conditions. 相似文献
407.
The composition and structure of tree stands near the timberline have been studied on different slopes and at different elevations
in the Tylaisko-Konzhakovsko-Serebryanskii Massif, the North Urals. It has been found that the upper limits of tree stands
with different degrees of canopy closure have risen considerably (by about 100 m of elevation) since the mid-19th century,
although the formation of these stands started as early as the late 18th century. Woodless areas in the eastern part of the
massif started to be colonized by Larix sibirica in the late 18th to early 19th centuries; those in the western part, by Picea obovata in the mid-19th century; and in the southern part, by Betula tortuosa in the late 19th century. Analysis of meteorological data provides evidence for warming and increasing humidity of the climate
since the late 19th century. Favorable climatic changes that facilitated the expansion of the forest have taken place both
in the summer (prolongation of the growing period) and in winter seasons (increase of air temperature and precipitation).
The observed differences in the composition and dynamics of tree stands between the studied areas of the mountain range are
most probably explained by different requirements of tree species for the depth of snow cover and the degree of soil freezing. 相似文献
408.
Konstantinos C. Makris Dibyendu Sarkar Jason Salazar Pravin Punamiya Rupali Datta 《Environmental science and pollution research international》2010,17(1):195-202
Background, aim, and scope
Alum (aluminum sulfate) is the currently preferred chemical amendment for phosphorus (P) treatment in poultry litter (PL). Aluminum-based drinking-water treatment residuals (Al-WTRs) are the waste by-product of the drinking-water treatment process and have been effectively used to remove P from aqueous solutions, but their effectiveness in PL water extracts has not been studied in detail. Elevated cost associated with alum could be minimized by using the equally effective WTRs to remove soluble P from PL, and they can be obtained at a minimal cost from drinking-water treatment plants. 相似文献409.
T. Glytsos J. Ondráček L. Džumbová I. Kopanakis M. Lazaridis 《Atmospheric environment (Oxford, England : 1994)》2010,44(12):1539-1549
Indoor sources have been identified as a major contributor to the increase of particle concentration in indoor environments. The work presented here is a study of the characteristics of particulate matter number size distribution and mass concentration under controlled indoor activities in a laboratory room. The objective is to characterize particulate matter concentrations indoors resulted under the influence of specific sources. Measurements were performed in an empty laboratory (period September–October 2006) using a GRIMM SMPS+C system (particle size range between 11.1 and 1083.3 nm), a DustTrak Aerosol Monitor (TSI) and a P-Trak Ultrafine Particle Counter (TSI). The studied indoor activities included candle burning, hot plate heating, water boiling, onion frying, vacuuming, hair drying, hair spraying, smoking and burning of incense stick. The AMANpsd computer algorithm was used to evaluate the modal structure of measured particle number size distribution data. Furthermore, the change of the particle number size distribution shape under the influence of different emission sources was studied versus time. Finally the particle emission rates were computed. High particle number concentrations were observed during smoking, onion frying, candle burning and incense stick burning. The highest particle mass concentrations were measured during smoking and hair spraying. The shift of the particle size distribution to larger diameters suggests the presence of strong coagulation effect during candle burning, incense stick burning, smoking and onion frying. The size distribution was mainly bimodal during onion frying and candle burning, whereas the size distribution remained unimodal during incense stick burning and smoking experiments. 相似文献
410.
AYESHA I. T. TULLOCH VIVITSKAIA J. D. TULLOCH MEGAN C. EVANS MORENA MILLS 《Conservation biology》2014,28(6):1462-1473
Understanding the social dimensions of conservation opportunity is crucial for conservation planning in multiple‐use landscapes. However, factors that influence the feasibility of implementing conservation actions, such as the history of landscape management, and landholders’ willingness to engage are often difficult or time consuming to quantify and rarely incorporated into planning. We examined how conservation agencies could reduce costs of acquiring such data by developing predictive models of management feasibility parameterized with social and biophysical factors likely to influence landholders’ decisions to engage in management. To test the utility of our best‐supported model, we developed 4 alternative investment scenarios based on different input data for conservation planning: social data only; biological data only; potential conservation opportunity derived from modeled feasibility that incurs no social data collection costs; and existing conservation opportunity derived from feasibility data that incurred collection costs. Using spatially explicit information on biodiversity values, feasibility, and management costs, we prioritized locations in southwest Australia to control an invasive predator that is detrimental to both agriculture and natural ecosystems: the red fox (Vulpes vulpes). When social data collection costs were moderate to high, the most cost‐effective investment scenario resulted from a predictive model of feasibility. Combining empirical feasibility data with biological data was more cost‐effective for prioritizing management when social data collection costs were low (<4% of the total budget). Calls for more data to inform conservation planning should take into account the costs and benefits of collecting and using social data to ensure that limited funding for conservation is spent in the most cost‐efficient and effective manner. 相似文献