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41.
Lúcio Costa Proença Enedir Ghisi Davi da Fonseca TavaresGabriel Marcon Coelho 《Resources, Conservation and Recycling》2011,55(11):960-965
Nowadays, it is very important that water and energy resources are used appropriately as this is a challenge to promote sustainable development. In some sectors, such as water and sewerage utilities, energy consumption depends on water consumption. The main objective of this work is to estimate the potential for electricity savings in a water and sewerage utility by reducing potable water consumption in the residential, commercial and public sectors in the city of Florianópolis, southern Brazil. These three sectors account for 98.9% of the total water consumption in the city. By using data related to energy consumption and costs that apply to the local water utility for water and sewage treatment, and also the potential for potable water savings over the three sectors, it is possible to estimate the potential for energy savings by reducing potable water consumption and sewage treatment. Potable water savings were estimated by using data available in the literature about water end-uses for different types of buildings located in Florianópolis. Three options were considered: installing dual-flush toilets, reusing greywater and using rainwater. The average potential for potable water savings were 30.0%, 53.4% and 60.3%, respectively, for the residential, commercial and public sectors. Thus, the average potable water savings amount to about 10,153,835 m3/year, and the electricity savings amount to 4.4 GW h/year, which would be enough to supply 1217 houses or flats in Florianópolis, with an average energy consumption of 300 kW h/month. 相似文献
42.
Sadauskas-Henrique H Sakuragui MM Paulino MG Fernandes MN 《Environmental monitoring and assessment》2011,181(1-4):29-42
The condition factor and blood variables, including erythrocyte lipid peroxidation (LPO) and the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), in two ecologically distinct fish species (Astyanax fasciatus and Pimelodus maculatus) were evaluated at five sites in the Furnas Hydroelectric Power Station reservoir (Brazil) to assess water quality. Aldrin/dieldrin, endosulfan, heptachlor epoxide, and metolachlor were detected at different concentrations in four of the sites. Condition factor was not directly affected by such contaminants. A negative correlation between hematocrit and heptachlor was detected in P. maculatus. Positive correlations between red blood cells and heptachlor as well as an interactive effect of metolachlor and aldrin/dieldrin were detected in A. fasciatus. The erythrocytes of both species collected from the contaminated sites showed high levels of LPO, an increase in SOD and GPx activities and a decrease in CAT activity. Although the leukocyte number and the differential percentage of leukocytes varied among the sites, the hematological variables, the LPO levels, and the antioxidant enzyme activities could be used to assess water quality, regardless of the differences in the responses of the fish species. 相似文献
43.
Baganha Baptista PR Bernardes C Cunha TR 《Environmental monitoring and assessment》2011,179(1-4):589-604
Government and environmental entities are becoming increasingly concerned with qualifying and quantifying the erosion effects that are observed in sandy shores. Correspondingly, survey methodologies that gather data for such erosion studies are increasingly being demanded. The responsible entities are continually broadening their areas of interest, are concerned in the establishment of regular monitoring programmes and are demanding high accuracy from the geo-spatial data that is collected. The budget available for such monitoring activities, however, does not parallel the trend in the increasing demand for quality specifications. Survey methodologies need improvement to meet these requirements. We have developed a new land-based survey system--the INSHORE system--that is ideal for low cost, highly efficient and highly precise coastal surveys. The INSHORE system uses hi-tech hardware that is based on high-grade global positioning system (GPS) receivers and a laser distance sensor combined with advanced software algorithms. This system enables the determination of the ground coordinates of the surveyed areas with a precision of 1 to 2 cm, without having a sensor in contact with the ground surface. The absence of physical contact with the ground makes this system suitable for high-efficiency surveys. The accuracy of the positioning, which is based on advanced differential GPS processing, is enhanced by considering the estimated attitude of the GPS receiver holding structure and eliminates undesirable offsets. This paper describes the INSHORE survey system and presents the results of validation tests that were performed in a sandy shore environment. 相似文献
44.
Strong variability in bacterioplankton abundance and production in central and western Bay of Bengal
Veronica Fernandes Nagappa Ramaiah Jane T. Paul Sugandha Sardessai R. Jyoti Babu Mangesh Gauns 《Marine Biology》2008,153(5):975-985
With large influx of freshwater that decreases sea-surface salinities, weak wind forcing of <10 m s−1 and almost always warm (>28°C) sea-surface temperature that stratifies and shallows the mixed layer leading to low or no
nutrient injections into the surface, primary production in Bay of Bengal is reportedly low. As a consequence, the Bay of
Bengal is considered as a region of low biological productivity. Along with many biological parameters, bacterioplankton abundance
and production were measured in the Bay of Bengal during post monsoon (September–October 2002) along an open ocean transect,
in the central Bay (CB, 88°E) and the other transect in the western Bay (WB). The latter representing the coastal influenced
shelf/slope waters. Bacterioplankton abundances (<2 × 109cells l−1) were similar to those reported from the HNLC equatorial Pacific and the highly productive northern Arabian Sea. Yet, the
thymidine uptake rates along CB (average of 1.46 pM h−1) and WB (average of 1.40 pM h−1) were less than those from the northwestern Indian Ocean. These abundances and uptake rates were higher than those in the
oligotrophic northwestern Sargasso Sea (<7 × 108 cells l−1; av 1.0 pM h−1). Concentrations of chlorophyll a (chl a), primary production rates and total organic carbon (TOC) were also measured for a comparison of heterotrophic and autotrophic
production. In the WB, bacterioplankton carbon biomass equaled ∼ 95% of chl a carbon than just 31% in the CB. Average bacterial:primary production (BP:PP) ratios accounted for 29% in the CB and 31% in
the WB. This is mainly due to lower primary productivity (PP) in the WB (281 mg C m−2 d−1) than in the CB (306 mg C m−2 day−1). This study indicates that bacteria–phytoplankton relationship differs in the open (CB) and coastal waters (WB). Higher
abundance and contrastingly low bacterial production (BP) in WB may be because of the riverine bacteria, brought in through
discharges, becoming dormant and unable to reproduce in salinities of 28 or more psu. Heterotrophic bacteria appear to utilize
in situ DOC rather rapidly and their carbon demand is ∼50% of daily primary production. It is also apparent that allochthonous
organic matter, in particular in the western Bay, is important for meeting their carbon demand. 相似文献
45.
A. Roulin J. Gasparini P. Bize M. Ritschard H. Richner 《Behavioral ecology and sociobiology》2008,62(4):507-519
One hypothesis for the maintenance of genetic variation states that alternative genotypes are adapted to different environmental
conditions (i.e., genotype-by-environment interaction G×E) that vary in space and time. Although G×E has been demonstrated
for morphological traits, little evidence has been given whether these G×E are associated with traits used as signal in mate
choice. In three wild bird species, we investigated whether the degree of melanin-based coloration, a heritable trait, covaries
with nestling growth rate in rich and poor environments. Variation in the degree of reddish-brown phaeomelanism is pronounced
in the barn owl (Tyto alba) and tawny owl (Strix aluco), and variation in black eumelanism in the barn owl and Alpine swift (Apus melba). Melanin-based coloration has been shown to be a criterion in mate choice in the barn owl. We cross-fostered hatchlings
to test whether nestlings sired by parents displaying melanin-based colorations to different extent exhibit alternative growth
trajectories when raised by foster parents in poor (experimentally enlarged broods) and rich (experimentally reduced broods)
environments. With respect to phaeomelanism, barn owl and tawny owl offspring sired by redder parents grew more rapidly in
body mass only in experimentally reduced broods. With respect to eumelanism, Alpine swift offspring of darker fathers grew
their wings more rapidly only in experimentally enlarged broods, a difference that was not detected in reduced broods. These
interactions between parental melanism and offspring growth rate indicate that individuals display substantial plasticity
in response to the rearing environment which is associated with the degree of melanism: at least with respect to nestling
growth, phaeomelanic and eumelanic individuals are best adapted to rich and poor environments, respectively. It now remains
to be investigated why eumelanism and phaeomelanism have a different signaling function and what the lifelong consequences
of these melanism-dependent allocation strategies are. This is important to fully appraise the role played by environmental
heterogeneity in maintaining variation in the degree of melanin-based coloration. 相似文献
46.
Heavy metal distribution in sediments and ecological risk assessment: The role of diagenetic processes in reducing metal toxicity in bottom sediments 总被引:18,自引:0,他引:18
Fernandes HM 《Environmental pollution (Barking, Essex : 1987)》1997,97(3):317-325
This paper describes the heavy metal distributions in river and lagoonal sediments of Jacarepaguá Basin, Rio de Janeiro, Brazil. The occurrence of metal phase translocation from the reducible to the oxidizable was observed for Fe, Mn and Ni, from the fluvial environment to the lagoonal. Cu was mainly associated with the oxidizable phase while Zn and Pb were mainly associated with the reducible phase in both environments. It has been demonstrated that metal sulfide formation and complexation by organic complexes are very important aspects in terms of toxicity reduction. By means of a risk assessment methodology, based on available sediment data, it was demonstrated that the lagoonal system is exposed to a low potential ecological risk and that Zn was the metal of greater concern with respect to the system pollution. 相似文献
47.
After the prohibition of organochlorine-pesticide use in Brazil for controlling insect vector diseases, Mato Grosso State gathered the exceeding DDT and stored it irregularly in an open air area that belongs to the National Health Foundation, causing soil contamination. This study aimed to evaluate the contamination level and dissipation of p,p'-DDT and p,p'-DDE in this area. For that, surface soil samples were collected on 19 September 2000, 15 December 2000, 4 April 2001 and soil samples 30-40 cm; 60-70 cm and 90-100 cm deep were taken from five points in the studied area on 17 July 2001. The contaminants were determined by a small scale method which consists on extraction and clean-up steps combined into one step by transferring soil samples mixed with neutral alumina to a chromatographic column prepacked with neutral alumina and elution with hexane:dichloromethane (7:3 v:v). The eluate was concentrated and the analytes were quantified by gas chromatography with an electron-capture detector. p,p'-DDT at surface soil ranged from 3,800 to 7,300 mg kg(-1). 30-40 cm deep soil sample concentrations varied from 0.036 to 440 mg kg(-1) while 90-100 cm deep samples varied from 0.069 to 180 mg kg(-1). Volatilization is probably the main dissipation process. The p,p'-DDT is moving slowly downward in the soil profile, however, the levels of this contaminant are high enough to present risk to underground waters. 相似文献
48.
49.
Fernandes Francine Faia Moura Bárbara Baesso 《Environmental science and pollution research international》2021,28(31):41726-41735
Environmental Science and Pollution Research - The present study evaluates the development of visible injury related to phytotoxic ozone dose (PODy) in native tropical species Astronium graveolens... 相似文献
50.
A.?T.?FordEmail author T.?P.?Rodgers-Gray I.?M.?Davies A.?M.?Dunn P.?A.?Read C.?D.?Robinson J.?E.?Smith T.?F.?Fernandes 《Marine Biology》2005,147(4):1053-918
Recent reports have demonstrated a cost associated with intersexuality in Amphipoda, including reduced fecundity and fertility. In this study, the gross morphology of the gonads in normal and intersex Echinogammarus marinus (Amphipoda) were compared to determine whether resource allocation to gonadal tissue accounted for this reduced fitness. Evidence for the presence of the male sex-determining hormone, androgenic gland hormone (AGH), was compared between sexual phenotypes using MALDI mass spectrometry. Two distinct intersex phenotypes (male intersex and female intersex) were found, with variation in gonadal structure corresponding with external phenotype. Examination of male intersexes revealed normal testicular development (testes, seminal vesicles and vas deferens), but also revealed the formation of an oviduct. Ovaries of intersex females showed normal ovarian development, but were reduced in length by approximately 20% due to the presence of vas deferens. The number of vas deferens in intersex females was equal to the number (one or two) of genital papillae. We hypothesise that the reduced ovarian length observed in intersex females is a likely cause of the reduced brood size previously reported in intersex females of this species. Variation in the sexual phenotype corresponded both to development of the androgenic gland and to expression of a peptide fragment corresponding to the A chain of androgenic gland hormone (AGH). Androgenic glands and a putative AGH peptide were present in males. However, in both normal and intersex females, the androgenic glands were only present in a rudiment form and the peptide was not detected. Intersex males were found to possess abnormal glands that appeared hypertrophied. However, AGH peptides were not detected, supporting the suggestion that the intersex phenotype is manifested via perturbations of AGH.An erratum to this article can be found at
Communicated by J.P. Thorpe, Port Erin 相似文献