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31.
Carlos Afonso Teixeira Catarina Avelino Fátima Ferreira Isabel Bentes 《Waste management (New York, N.Y.)》2014,34(9):1584-1594
The increase of Municipal Solid Waste (MSW) generated over the last years forces waste managers pursuing more effective collection schemes, technically viable, environmentally effective and economically sustainable. The assessment of MSW services using performance indicators plays a crucial role for improving service quality. In this work, we focus on the relevance of regular system monitoring as a service assessment tool. In particular, we select and test a core-set of MSW collection performance indicators (effective collection distance, effective collection time and effective fuel consumption) that highlights collection system strengths and weaknesses and supports pro-active management decision-making and strategic planning. A statistical analysis was conducted with data collected in mixed collection system of Oporto Municipality, Portugal, during one year, a week per month. This analysis provides collection circuits’ operational assessment and supports effective short-term municipality collection strategies at the level of, e.g., collection frequency and timetables, and type of containers. 相似文献
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Catarina Vinagre Filipe Duarte Santos Henrique Cabral Maria José Costa 《Regional Environmental Change》2011,11(4):779-789
Impact of sea-surface warming upon the fish assemblages of the Portuguese coast was assessed under two scenarios, the A2 and
the B2 scenarios (Special Report on Emission Scenarios), which when coupled with a regional circulation model HadRM3 predict
1 and 2°C of sea-surface warming until the year 2100. Species richness increased in the Portuguese coast. In both scenarios,
there was a latitudinal gradient in the amount of lost and gained species, increasing from north to south. An anomaly in the
latitudinal gradient of species richness was detected in the southernmost area, which presented the lowest species richness
of all areas, in the A2 scenario, and appears to be particularly vulnerable to climate change. Very few species were totally
eliminated from Portuguese waters. For the Portuguese coast as a whole, there were more new than lost species, in both scenarios.
Most of the new species were commercially important species, in the majority subtropical in the north and tropical in the
south, mainly demersal and reef-associated. Reef-associated species also increased in relative importance. A commercial opportunity
for fisheries may arise from climate warming, since most of the new species were commercial species and not many commercial
species were lost. An increasing gradient from north to south was detected in the colonization of new species of herbivores,
planktivores, and omnivores, as well as lower mean trophic level, which might have consequences for the future of trophic
webs. 相似文献
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Catarina Vinagre Luís Narciso Marta Pimentel Henrique N. Cabral Maria J. Costa Rui Rosa 《Regional Environmental Change》2013,13(4):853-859
The Senegal sole, Solea senegalensis, is a species of flatfish that has several distinct cohorts of 0-group juveniles which use estuarine nurseries in summer and winter. The early cohort is more abundant and grows faster than the late cohort that stays in the nurseries during winter; however, climate warming may have an impact on the dynamics of this species’ juveniles. This study aimed to compare mortality, metabolic response and growth of S. senegalensis juveniles at different temperatures, reflecting present-day temperature (winter—12 °C; summer—24 °C) and future temperature (plus 3 °C) conditions, in estuarine nurseries in the southern European population. Mortality was low at 12 °C, being only 10 %, increasing to 30 % at 15 °C, 40 % at 24 °C and at 27 °C it hit 70 %. Metabolic rate increased steadily with increasing temperatures, yet it increased steeply from 24 to 27 °C. Thermal sensitivity was high for the temperature interval between 24 and 27 °C. Growth was very slow at 12 °C, at a rate of 0.03 mm day?1, increasing to 0.22 mm day?1 at 15 °C, and to 0.60 mm day?1, at 24 °C. However, at 27 °C growth rapidly declined to 0.12 mm day?1. Warming will be beneficial for the late cohort, resulting in a major increase in growth. However, the early cohort will not benefit from warming, due to high mortality and arrested growth, which clearly indicates that this species is under severe thermal stress at 27 °C. Thus, here we show, for the first time, that climate change may induce contrasting seasonal impacts on fish bio-ecology and physiology, namely in species with several cohorts over the course of the year. Phenotypic and/or genotypic plasticity may limit the impacts of climate change. 相似文献
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Ana Catarina Ferreira Silva Sónia Brazão Steve J. Hawkins Richard C. Thompson Diana M. Boaventura 《Marine Biology》2009,156(12):2591-2599
Wave action is known to influence the abundance and distribution of intertidal organisms. Wave action will also determine
the duration and suitability of various foraging windows (high-tide and low-tide, day and night) for predation and can also
affect predator behaviour, both directly by impeding prey handling and indirectly by influencing prey abundance. It remains
uncertain whether semi-terrestrial mobile predators such as crabs which can access intertidal prey during emersion when the
effects of wave action are minimal, are influenced by exposure. Here, we assessed the effect of wave action on the abundance
and population structure (size and gender) of the semi-terrestrial intertidal crab Pachygrapsus marmoratus on rocky shores in Portugal. The activity of P. marmoratus with the tidal cycle on sheltered and exposed shores was established using baited pots at high-tide to examine whether there
was activity during intertidal immersion and by low-tide searches. Because prey abundance varies along a wave exposure gradient
on most Portuguese shores and because morphology of crab chelipeds are known to be related to diet composition, we further
tested the hypothesis that predator stomach contents reflected differences in prey abundance along the horizontal gradient
in wave exposure and that this would be correlated with the crab cheliped morphology. Thus, we examined phenotypic variation
in P. marmoratus chelipeds across shores of differing exposure to wave action. P. marmoratus was only active during low-tide. Patterns of abundance and population structure of crabs did not vary with exposure to wave
action. Stomach contents, however, varied significantly between shores of differing exposure with a higher consumption of
hard-shelled prey (mussels) on exposed locations, where this type of prey is more abundant, and a higher consumption of barnacles
on sheltered shores. Multivariate geometric analysis of crab claws showed that claws were significantly larger on exposed
shores. There was a significant correlation between animals with larger claws and the abundance of mussels in their stomach.
Variation in cheliped size may have resulted from differing food availability on sheltered and exposed shores. 相似文献
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Alves E Velini ED Trindade ML Cataneo AC Marino CL Mori ES Guerrini IA Furtado EL Wilcken CF 《Journal of environmental science and health. Part. B》2005,40(1):151-157
Oxidative stress generating active oxygen species has been proved to be one of the underlying agents causing tissue injury after the exposure of Eucalyptus (Eucalyptus spp.) plants to a wide variety of stress conditions. The objective of this study was to perform data mining to identify favorable genes and alleles associated with the enzyme systems superoxide dismutase, catalase, peroxidases, and glutathione S-transferase that are related to tolerance for environmental stresses and damage caused by pests, diseases, herbicides, and by weeds themselves. This was undertaken by using the eucalyptus expressed-sequence database (https//forests.esalq.usp.br). The alignment results between amino acid and nucleotide sequences indicated that the studied enzymes were adequately represented in the ESTs database of the FORESTs project. 相似文献
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Pilar D. S. C. Mariani Antonio P. Vinagre Neto José P. da Silva Jr. Elke J. B. N. Cardoso Elisa Esposito Lucia H. Innocentini-Mei 《Journal of Polymers and the Environment》2007,15(1):19-24
The biodegradability properties of poly(ɛ-caprolactone) (PCL) and modified adipate-starch (AS) blends, using Edenol-3203 (E)
as a starch plasticizer, were investigated in laboratory by burial tests of the samples in previously analyzed agricultural
soil. The biodegradation process was carried out using the respirometric test according to ASTM D 5988-96, and the mineralization
was followed by both variables such as carbon dioxide evolution and mass loss. The results indicated that the presence of
AS-E accelerated the biodegradation rate as expected. 相似文献
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Estuarine ecosystems in SE Asia have been poorly studied when compared to other tropical environments. Important gaps exist particularly in the understanding of their biogeochemical function and contribution to global change. In this work we looked into N-turnover in the water column and sediments of the Bangpakong estuary(13°N). A seasonal sampling program was performed along the salinity gradient covering different stretches of the estuary(68 km).Key physical and chemical characteristics were also monitored in order to unravel possible environmental controls. Results showed the occurrence of active denitrification in sediments(5.7–50.9 nmol N-N2/(cm3·hr)), and water column(3.5–1044 pmol N-N2/(cm3·hr)). No seasonal or spatial variability was detected for denitrification potential in sediment samples. However, in the water column, the denitrification activity peaked during the transition season in the downstream sites coinciding with high turbidity levels. Therefore, in that period of the year, the water column compartment may be an important contributor to nitrate reduction within the estuary. The rather low nitrification rates detected were not always measurable, probably due to the reduced oxygen content and high siltation. This study is one of the few dealing simultaneously with sediments and water column processes in a highly turbid tropical estuary.Therefore, it emerges as a valuable contribution for the understanding of the dynamics of the nitrogen cycle in tropical environments by exploring the role of estuarine N microbial activity in reducing the effects of increased nitrogen loads. 相似文献
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Maria João Rocha Marta Ribeiro Cláudia Ribeiro Cristina Couto Catarina Cruzeiro Eduardo Rocha 《毒物与环境化学》2013,95(2):262-274
The Leça River and two beaches close to the north and south margins of the estuary, nowadays an important seaport harbor, show signs of contamination. However, the chemical nature of that contamination is uncertain. Therefore, this study checked for the presence of 11 endocrine disrupting compounds (EDCs) of animal (17β-estradiol and estrone), pharmaceutical (17α-ethynylestradiol), and industrial (alkylphenols, alkylphenol ethoxylates, and bisphenol A) origins in water samples collected from six points at the river gradient and at two sites in the coastline (Atlantic Ocean). Along with the EDCs, evaluated by gas chromatography – mass spectroscopy (GC-MS) during spring, summer, and autumn, physico-chemical parameters were also assessed and particular attention was given to dissolved oxygen (DO) levels. Data showed the presence of high amounts of estrogens (up to 10?ng?L?1 for estrone) and industrial compounds (up to 2?µg?L?1 for the nonylphenol ethoxylates) at both river and seacoast. Along with this, clear signs of hypoxia were found in the river (DO?3?mg?L?1 at several sampling sites). Taking into account these issues, it was concluded that there are local conditions for the occurrence of endocrine disruption in aquatic animals. 相似文献
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