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1.
Public Health ; 230: 12-20, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479163

RESUMO

OBJECTIVE: This article aims to estimate the differences in environmental impact (greenhouse gas [GHG] emissions, land use, energy used, acidification and potential eutrophication) after one year of promoting a Mediterranean diet (MD). METHODS: Baseline and 1-year follow-up data from 5800 participants in the PREDIMED-Plus study were used. Each participant's food intake was estimated using validated semi-quantitative food frequency questionnaires, and the adherence to MD using the Dietary Score. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The association between MD adherence and its environmental impact was calculated using adjusted multivariate linear regression models. RESULTS: After one year of intervention, the kcal/day consumed was significantly reduced (-125,1 kcal/day), adherence to a MD pattern was improved (+0,9) and the environmental impact due to the diet was significantly reduced (GHG: -361 g/CO2-eq; Acidification:-11,5 g SO2-eq; Eutrophication:-4,7 g PO4-eq; Energy use:-842,7 kJ; and Land use:-2,2 m2). Higher adherence to MD (high vs. low) was significantly associated with lower environmental impact both at baseline and one year follow-up. Meat products had the greatest environmental impact in all the factors analysed, both at baseline and at one-year follow-up, in spite of the reduction observed in their consumption. CONCLUSIONS: A program promoting a MD, after one year of intervention, significantly reduced the environmental impact in all the factors analysed. Meat products had the greatest environmental impact in all the dimensions analysed.


Assuntos
Dieta Mediterrânea , Gases de Efeito Estufa , Humanos , Dieta , Meio Ambiente , Coleta de Dados
2.
Sci Total Environ ; 940: 173440, 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-38802018

RESUMO

Despite their ability to mitigate climate change by efficiently absorbing atmospheric carbon dioxide (CO2) and acting as natural long-term carbon sinks, mangrove ecosystems have faced several anthropogenic threats over the past century, resulting in a decline in the global mangrove cover. By using standardized methods and the most recent Bayesian tracer mixing models MixSIAR, this study aimed to quantify source contributions, burial rates, and stocks of organic carbon (Corg) and explore their temporal changes (∼100 years) in seven lead-210 dated sediment cores collected from three contrasting Mexican mangrove areas. The spatial variation in Corg burial rates and stocks in these blue carbon ecosystems primarily depended on the influence of local rivers, which controlled Corg sources and fluxes within the mangrove areas. The Corg burial rates in the cores ranged from 66 ± 16 to 400 ± 40 g m-2 yr-1. The Corg stocks ranged from 84.9 ± 0.7 to 255 ± 2 Mg ha-1 at 50 cm depth and from 137 ± 2 to 241 ± 4 Mg ha-1 at 1 m depth. The highest Corg burial rates and stocks were observed in cores from the carbonate platform of Yucatan and in cores with reduced river influence and high mangrove detritus inputs, in contrast to patterns identified from global databases. Over the past century, the rising trends in Corg burial rates and stocks in the study sites were primarily driven by enhanced inputs of fluvial-derived Corg and, in some cores, mangrove-derived Corg. Despite their decreasing extension, mangrove areas remained highly effective producers and sinks of Corg. Ongoing efforts to enhance the global database should continue, including mangrove area characteristics and reliable timescales to facilitate cross-comparison among studies.

3.
Bull Environ Contam Toxicol ; 91(1): 42-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23595347

RESUMO

Hg was analyzed in seven tissues of 52 common shoveler Anas clypeata collected from the coast of SE Gulf of California. Mean Hg concentrations were highest in the liver (2,885 ng g⁻¹) and lowest in the gizzard (621 ng g⁻¹); they followed the order: liver, feathers > muscle tissue and tissues of the circulatory system > digestive organs. Hg levels were similar or higher than birds of the same trophic level and feeding habits. Considering the relationships of Hg among tissues and blood we recommend the use of blood as an efficient method to monitor Hg.


Assuntos
Patos/metabolismo , Exposição Ambiental , Monitoramento Ambiental/métodos , Mercúrio/sangue , Poluentes Químicos da Água/sangue , Animais , Cadeia Alimentar , Mercúrio/metabolismo , México , Espectrofotometria Atômica , Distribuição Tecidual , Poluentes Químicos da Água/metabolismo
4.
Mol Cell Biochem ; 351(1-2): 59-64, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21264498

RESUMO

Left ventricular hypertrophy is an adaptive response to hypertension, and an independent clinical risk factor for cardiac failure, sudden death, and myocardial infarction. As regression of cardiac hypertrophy is associated with a lower likelihood of cardiovascular events, it is recognized as a target of antihypertensive therapy. This necessitates identification of factors associated with the initiation and progression of hypertrophy. Oxidative stress and metabolic shift are intimately linked with myocardial hypertrophy, but their interrelationship is not clearly understood. This study proposes to identify the temporal sequence of events so as to distinguish whether oxidative stress and metabolic shift are a cause or consequence of hypertrophy. Spontaneously hypertensive rat (SHR) was used as the experimental model. Cardiac hypertrophy was apparent at 2 months of age, as assessed by hypertrophy index and brain natriuretic peptide gene expression. Enhanced myocardial lipid peroxidation accompanied by nuclear factor-kappa B gene expression in one-month-old SHR suggests that oxidative stress precedes the development of hypertrophy. Metabolic shift identified by reduction in the expression of peroxisome proliferator-activated receptor-alpha, medium chain acyl CoA dehydrogenase, and carnitine palmitoyltransferase 1ß was seen at 4 months of age, implying that reduction of fatty acid oxidation is a consequence of hypertrophy. Information on the temporal sequence of events associated with hypertrophy will help in the prevention and reversal of cardiac remodeling. Investigations aimed at prevention of hypertrophy should address reduction of oxidative stress. Both, oxidative stress and metabolic modulation have to be considered for studies that focus on the regression of hypertrophy.


Assuntos
Cardiomegalia/metabolismo , Ácidos Graxos/metabolismo , Hipertensão/metabolismo , Estresse Oxidativo , Animais , Sequência de Bases , Primers do DNA , Ratos , Ratos Endogâmicos SHR
5.
Clin Trials ; 8(2): 205-13, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21270141

RESUMO

BACKGROUND: Matriculation from high school to college is typified by an increase in alcohol use and related harm for many students. Therefore, this transition period is an ideal time for preventive interventions to target alcohol use and related problems. PURPOSE: The purpose of this report is to describe the design and methods used in the Transitions Project, a randomized controlled trial of two interventions designed to prevent and reduce heavy episodic drinking and alcohol-related negative consequences among incoming college students. METHODS: This study used a 2 × 2 factorial design to investigate the effects of a two-session brief motivational intervention delivered to students and a handbook-based parent intervention. Interventions were administered to students and parents. Follow-up assessment took place at 10- and 22-months post-baseline. RESULTS: The Transitions Project successfully recruited and retained participants across a major transition period (i.e., entering college), administered and compared two distinct but complementary interventions, and collected and analyzed highly skewed data. The application of a factorial design and two-part latent growth curve modeling allowed us to examine main and interactive intervention effects in terms of both initiation and growth in heavy drinking and alcohol-related problems. LIMITATIONS: While we conducted successful tests of our primary and secondary study hypotheses over a lengthy follow-up period, our study design did not permit full interpretation of null findings. We suggest that researchers carefully consider assessment timing, tests of assessment reactivity, and ensure objective tests of intervention efficacy when conducting clinical trials of motivational interventions. CONCLUSIONS: The lessons we learned while conducting this trial have the potential to assist other researchers designing and conducting future preventive interventions targeting parents and college students. The data analytic procedures presented can also help guide trials that plan to analyze zero-inflated non-normal outcome data.


Assuntos
Consumo de Bebidas Alcoólicas/prevenção & controle , Intoxicação Alcoólica/prevenção & controle , Etanol/intoxicação , Motivação , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Adolescente , Adulto , Aconselhamento , Retroalimentação , Feminino , Humanos , Masculino , Manuais como Assunto , Relações Pais-Filho , Pais , Estudantes , Adulto Jovem
6.
Bull Environ Contam Toxicol ; 86(2): 180-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21234535

RESUMO

A hazard quotient (HQ) was evaluated for Mexican population considering Hg levels and consumption rates. Fish and shrimp were caught in selected coastal areas. HQ's ranged from 0.004 to 0.01 in shrimp; from 0.004 to 1.04 in fish from NW Mexico; and from 0.02 to 0.19 in fish from the Gulf of Mexico. Highest HQ in fish were found in carnivorous fish Caranx caninus (HQ = 0.71) and Sphyrna lewini (HQ = 1.04) from NW Mexico. A more accurate study should be made considering organic Hg, contribution of Hg from other sources, and consumption rates according to age, sex and economic status.


Assuntos
Dieta/estatística & dados numéricos , Exposição Ambiental/análise , Mercúrio/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Animais , Exposição Ambiental/estatística & dados numéricos , Monitoramento Ambiental , Peixes/metabolismo , Humanos , Mercúrio/metabolismo , México , Penaeidae/metabolismo , Medição de Risco , Alimentos Marinhos/estatística & dados numéricos , Poluentes Químicos da Água/metabolismo
7.
Mar Pollut Bull ; 159: 111490, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32738641

RESUMO

Laboratories from 14 countries (with different levels of expertise in radionuclide measurements and 210Pb dating) participated in an interlaboratory comparison exercise (ILC) related to the application of 210Pb sediment dating technique within the framework of the IAEA Coordinated Research Project. The laboratories were provided with samples from a composite sediment core and were required to provide massic activities of several radionuclides and an age versus depth model from the obtained results, using the most suitable 210Pb dating model. Massic concentrations of Zn and Cu were also determined to be used for chronology validation. The ILC results indicated good analytical performances while the dating results didn't demonstrate the same degree of competence in part due to the different experience in dating of the participant laboratories. The ILC exercise enabled evaluation of the difficulties faced by laboratories implementing 210Pb dating methods and identified some limitations in providing reliable chronologies.


Assuntos
Radioisótopos de Chumbo/análise , Chumbo , Monitoramento Ambiental , Sedimentos Geológicos , Humanos , Radiometria
8.
Mar Pollut Bull ; 156: 111245, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32510387

RESUMO

The development of the Grijalva-Usumacinta river basin exerts modifications on its discharge area. A sediment core was studied to reconstruct environmental changes and trace element contamination status during the past 45 years. 210Pb-derived mass accumulation rates indicate higher sediment input to the area since 1995, related to increased precipitation and floodings in the catchment area. Sediments show finer particles from the late 1970s on, likely related to dams construction upriver and/or land use changes. Heavy metal enrichment factors (EF < 2) suggest minimum contamination. Benthic foraminifera and redox-sensitive - elements (As, Ba, Co, Cr, Cu, Ni, Pb, V and Zn) indicate the sediments before 2000 were deposited under oxygenated conditions. Afterwards, environmental conditions changed and benthic foraminifera and dinocysts assemblages changed suggesting eutrophication and lower oxygen conditions during the last 20 years. Monitoring should be continued to assess eutrophication/hypoxic/pollution trends that could become deleterious to the marine biota.


Assuntos
Metais Pesados/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Sedimentos Geológicos , Golfo do México , Rios
9.
Sci Total Environ ; 651(Pt 2): 3174-3186, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30463167

RESUMO

Trace element (As, Co, Cr, Cu, Ni, Pb, V and Zn) enrichment trends during the past century, were assessed in thirteen 210Pb-dated sediment cores from the southern Gulf of Mexico, with the purpose to evaluate the impact on the environment, and potentially on public health, of the offshore oil industry and of oil spills such as that of the Ixtoc1 well blowout in 1979. The trace element composition was quite homogeneous among cores; and the pre-industrial concentrations of Ba, Cr, Cu and Ni are naturally high in the region, as to reach levels of potential ecological concern. The influence of multiple and simultaneous processes (e.g. industrial activities, natural seeps, fluvial discharges) on the trace element concentrations is difficult to disentangle. Some cores suggested long-term preservation of putative oil spill traces, although it was not possible to attribute their origin. The Al-normalized redox element ratios, and the crude oil contamination ratio, suggested that these events occurred along almost four decades, and that the traces attributed to the Ixtoc1 spill were comparable to background conditions, most likely owing to active natural oil seeps in the area. In most cases there was a trend towards a lowering in the supply of trace elements; this might be associated with environmental controls in the region since the 1980s. This study highlights the relevance of using dated environmental archives to reconstruct the historical trends of trace metal contamination in areas where long-term environmental studies are scarce.

10.
Mar Pollut Bull ; 149: 110498, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31430665

RESUMO

Spatial and temporal variability of mercury concentrations in sediments was evaluated in 210Pb-dated sediment cores from offshore and intertidal areas in the southern Gulf of Mexico. In offshore cores, mercury concentrations were comparable (11.2-69.2 ng g-1), and intermediate between concentrations in intertidal cores from the eastern (6.0-34.4 ng g-1) and the western (34.9-137.7 ng g-1) inlets of Términos Lagoon. The enrichment factor (EF) indicated minimal contamination (EF < 2) in most offshore cores, whereas in some intertidal cores steadily increasing mercury enrichment and fluxes were observed along the past century. No evidence of oil industry related mercury contamination was found, as the minor but increasing enrichment in intertidal cores is most likely related to land-derived sources such as catchment eroded soils and waste water runoff. Results highlight the importance to control catchment erosion and untreated sewage releases to reduce mercury loadings to the coastal zone.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Mercúrio/análise , Solo/química , Poluentes Químicos da Água/análise , Golfo do México , Análise Espaço-Temporal
11.
Mar Environ Res ; 149: 111-125, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31280120

RESUMO

The Campeche Sound is the major offshore oil producing area in the Southern Gulf of Mexico (SGoM). To evaluate the impact of oil related activities in the ocean floor sediments, we analyzed the geochemical (major and trace element, organic carbon and hydrocarbon concentrations) and biological (benthic foraminifera) composition of 62 superficial sediment samples, from 13 to 1336 m water depth. Cluster and Factor analysis of all the variables indicate that their distribution patterns are mainly controlled by differences between the terrigenous and carbonate platforms in the SGoM. Benthic foraminiferal assemblages were abundant and diverse, and their distribution patterns are mainly determined by water depth and sedimentary environment. However, most of the abundant species are opportunistic and/or low-oxygen tolerant, and many of their tests show oil stains and infillings, characteristic of oil polluted locations, suggesting the environment has been modified by natural seepage or oil-related activities. To determine if these conditions are natural or anthropogenic in origin, pre - industrial settings should be studied. Organic carbon (Corg) content (0.6-2.9%) and total hydrocarbon concentrations (PAHs 1.0-29.5 µg kg-1) were usually higher around the oil platforms area, the natural hydrocarbon seeps ("chapopoteras") area and offshore rivers, but there is no accumulation of oil related trace elements in these areas. However, the comparison with international sediment quality benchmarks indicates that Cd, Cr and Ni concentrations are above the threshold effect level, and also As, Ba and Cu are above the probable effect level benchmarks, which indicate that these element concentrations might be of potential ecological concern. Comprehensive studies involving different proxies, and assessing pre-industrial conditions, must be undertaken before assessing environmental health of marine benthic ecosystems.


Assuntos
Monitoramento Ambiental , Foraminíferos/química , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Oligoelementos/análise , Poluentes Químicos da Água/análise , Biodiversidade , Foraminíferos/classificação , Golfo do México , Poluição por Petróleo
12.
Sci Total Environ ; 630: 1628-1640, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29554779

RESUMO

Coastal vegetated habitats can be important sinks of organic carbon (Corg) and mitigate global warming by sequestering significant quantities of atmospheric CO2 and storing sedimentary Corg for long periods, although their Corg burial and storage capacity may be affected by on-going sea level rise and human intervention. Geochemical data from published 210Pb-dated sediment cores, collected from low-energy microtidal coastal wetlands in El Salvador (Jiquilisco Bay) and in Mexico (Salada Lagoon; Estero de Urias Lagoon; Sian Ka'an Biosphere Reserve) were revisited to assess temporal changes (within the last 100years) of Corg concentrations, storage and burial rates in tropical salt marshes under the influence of sea level rise and contrasting anthropization degree. Grain size distribution was used to identify hydrodynamic changes, and δ13C to distinguish terrigenous sediments from those accumulated under the influence of marine transgression. Although the accretion rate ranges in all sediment records were comparable, Corg concentrations (0.2-30%), stocks (30-465Mgha-1, by extrapolation to 1m depth), and burial rates (3-378gm-2year-1) varied widely within and among the study areas. However, in most sites sea level rise decreased Corg concentrations and stocks in sediments, but increased Corg burial rates. Lower Corg concentrations were attributed to the input of reworked marine particles, which contribute with a lower amount of Corg than terrigenous sediments; whereas higher Corg burial rates were driven by higher mass accumulation rates, influenced by increased flooding and human interventions in the surroundings. Corg accumulation and long-term preservation in tropical salt marshes can be as high as in mangrove or temperate salt marsh areas and, besides the reduction of Corg stocks by ongoing sea level rise, the disturbance of the long-term buried Corg inventories might cause high CO2 releases, for which they must be protected as a part of climate change mitigation efforts.

13.
Mar Pollut Bull ; 104(1-2): 83-91, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26895596

RESUMO

Nutrient pollution causes environmental damages on aquatic ecosystems worldwide. Eutrophication produces impacts in coastal ecosystems, affecting biota and ecosystem services. The Urias coastal lagoon (SE Gulf of California) is a sub-tropical estuary under several environmental pressures such as nutrient inputs from shrimp farm effluents and dredging related to port operations, which can release substances accumulated in sediments. We assessed the water quality impacts caused by these activities and results showed that i) nitrogen was the limiting nutrient, ii) shrimp farm effluents increased particulate organic matter and chlorophyll a in the receiving stations, and iii) dredging activities increased nitrite and reduced dissolved oxygen concentrations. The co-occurrence of the shrimp farm releases and dredging activities was likely the cause of a negative synergistic effect on water quality which mainly decreases dissolved oxygen and increases nitrite concentrations. Coastal zone management should avoid the co-occurrence of these, and likely others, stressors in coastal ecosystems.


Assuntos
Aquicultura , Crustáceos/fisiologia , Monitoramento Ambiental , Estresse Fisiológico , Poluentes Químicos da Água/análise , Animais , California , Clorofila/análise , Clorofila A , Ecossistema , Meio Ambiente , Eutrofização , Nitrogênio/análise , Qualidade da Água
14.
Acta Biomater ; 1(2): 201-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16701797

RESUMO

Hydroxyapatite (HAP) is undoubtedly a material suitable for repairing the defective bone tissue. However, the brittleness and non-malleability of HAP limit its clinical application as a cranioplastic analogue. To improve these properties, pliable, osteoconductive composites composed of HAP and ethylene vinyl acetate co-polymer (EVA) have been developed. This study reports the biocompatibility evaluation of the newly developed composite material. Composites of two compositions, containing 40 and 50 volume percentage of HAP, were evaluated. In vitro cell culture cytotoxity studies were carried out using L929 cell line. Intracutaneous irritation studies, and intramuscular implantation studies were carried out on rabbits. Cell culture studies showed that the composite was non-cytotoxic to mouse fibroblast cell line. Intracutaneous irritation studies did not show any gross signs of tissue reaction. Histological analysis after six months of implantation in the paravertebral muscles of rabbit showed that all the implants under study were covered with a thin soft tissue capsule. On the basis of these observations, we conclude that the composite materials are biocompatible and hence are a candidate material for implantation in the cranium.


Assuntos
Materiais Biocompatíveis , Durapatita/química , Polivinil/química , Crânio/cirurgia , Animais , Linhagem Celular , Durapatita/administração & dosagem , Camundongos , Polivinil/administração & dosagem , Coelhos
16.
Toxicol Lett ; 15(4): 329-34, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6836601

RESUMO

Conclusive evidence for the presence of di(2-ethylhexyl) phthalate (DEHP) in 15 out of 17 commercially available sodium chloride injection (Indian Pharmacopoeia) samples was obtained and concentration levels as high as 11.0 mg/500 ml of saline were detected. The presence of such contaminants in i.v. fluids, avoidable by the institution of appropriate quality control measures before manufacturing and marketing, is a matter of serious concern. Stipulated specifications in different pharmacopoeias are meant only to ensure sterility and pyrogenicity, and it is advisable that cognisance be taken of the presence of toxic contaminants e.g. di(2-ethylhexyl) phthalate.


Assuntos
Dietilexilftalato/análise , Contaminação de Medicamentos , Ácidos Ftálicos/análise , Cloreto de Sódio/análise , Embalagem de Medicamentos , Vidro , Índia , Farmacopeias como Assunto , Cloreto de Polivinila , Controle de Qualidade , Soluções/análise , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
17.
Environ Pollut ; 125(3): 423-32, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12826420

RESUMO

Seven sediment cores (60-80 cm) were collected at Chiricahueto marsh, a salt marsh influenced by agrochemical, domestic and industrial effluents. The concentrations of Ag, Al, Cd, Co, Cu, Fe, Li, Mn, Pb, V and Zn were studied in the solid phase at each 1-cm section. The profiles of Ag, Cd, Cu, Mn, Ni, Pb and Zn showed a slight recent pollution in the site with enrichment and anthropogenic factors higher than unity; and correlation analysis indicated a direct association with organic carbon. Al, Co, Cr, Fe, Li, and V concentration profiles displayed a negative correlation with organic C and positive with mud content and no consistent enrichment at surface. Based on the principal component analysis and correlation analysis, two principal groups of metals were identified. The first group includes Al, Co, Cr, Fe and Li, that are derived predominantly from the weathering of parent materials in the local bedrock; and the second group include most of the metals, which were relatively enriched at surficial sediments, that are produced mainly by anthropogenic activities such as agriculture (Cd, Cu and Zn), sewage effluents (Ag, Cd, Cu, Ni, Pb and Zn) and in lesser extent atmospheric deposition (Cd and Pb).


Assuntos
Sedimentos Geológicos/química , Oligoelementos/análise , Poluentes Químicos da Água/análise , Agroquímicos/análise , México , Análise de Componente Principal , Água do Mar , Esgotos/química
18.
Environ Pollut ; 118(3): 365-77, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12009134

RESUMO

210Pb geochronology and sediment profiles of carbon, phosphorus and nitrogen were used to study time dependent changes in nutrients fluxes to Culiacan River Estuary. Results indicate that the release of urban sewage and agriculture wastes transported through Culiacan River has produced historically increased carbon, phosphorus and nitrogen fluxes to the study area. C:N:P elemental ratios showed that increments in the nutrients input begins simultaneously for C, N and P in 1948 with the clearing of the catchment for agriculture; although excess of nutrients input increased most importantly around the 1970s to roughly follow the rapidly growing population of Culiacan City. C/N ratios, delta13C and delta15N suggested that nutrient enrichment is mostly influenced by sewage delivered through Culiacan River.


Assuntos
Carbono/análise , Eutrofização , Sedimentos Geológicos/química , Nitrogênio/análise , Fósforo/análise , Agricultura , Monitoramento Ambiental , Radioisótopos de Chumbo/análise , México , Estudos Retrospectivos , Esgotos
19.
Mar Pollut Bull ; 46(7): 806-15, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12837298

RESUMO

Beginning in the middle of the 1980s, the Gulf of California ecoregion experienced a boom in shrimp aquaculture and became the second largest producer in the western hemisphere. The moderated, but continual development of shrimp farming, in conjunction with municipal and agriculture effluents has been accompanied by concern about: (a) depletion of fishing stocks, (b) reduction of mangrove forest, (c) frequent harmful algal blooms in coastal waters and shrimp ponds, and (d) water quality deterioration. We demonstrate that environmental degradation resulted from a conjunction of factors including agriculture, untreated municipal effluents, shrimp aquaculture, increasing number of fishermen, and an absence of an effective regulatory program. We recommend the immediate implementation of an integrated coastal management program to protect the integrity of the coastal ecosystems and operate upon the principle of environmental sustainability for the different economic activities including shrimp aquaculture.


Assuntos
Aquicultura , Conservação dos Recursos Naturais , Ecossistema , Penaeidae , Poluição da Água/prevenção & controle , Animais , Avicennia , California , Comércio , Meio Ambiente , Eutrofização , Pesqueiros
20.
Water Environ Res ; 76(1): 5-14, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15058459

RESUMO

The influent and effluent water quality of two ponds at four aquaculture facilities (two intensive and two semiintensive growout systems) located on the Northwest coast of Mexico was monitored. Temperature, salinity, pH, dissolved oxygen, biochemical oxygen demand (self-consumption in 48 hours), total suspended solids, particulate organic material, nitrite, nitrate, ammonium, reactive and total phosphate, and chlorophyll a were analyzed every 2 weeks during two consecutive growout cycles. Changes recorded in most of these water quality variables were not strongly related to the management practices of the ponds, but rather to environmental factors. The mean percent differences between inflowing and outflowing water that were observed indicated that water used for culture returned to the natural environment depleted of nutrients (inorganic nitrogen and reactive phosphate), and it was evident that the rearing activities promoted the exportation of particulate material to the surrounding environment.


Assuntos
Aquicultura , Penaeidae , Poluentes da Água/análise , Coleta de Dados , Eliminação de Resíduos Líquidos , Movimentos da Água
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