Long-term potential of in situ chemical reduction for treatment of polychlorinated biphenyls in soils.

Polychlorinated biphenyls (PCBs) are well-known for being hydrophobic and persistent in the environment. Although many treatment approaches have been demonstrated to result in degradation of PCBs in water or water/cosolvent systems, few examples exist where such approaches have been applied successfully for PCB degradation in soil-water systems. A possible explanation for the limited treatment of PCBs in soil-water systems is that reactants that are capable of degrading PCBs in the aqueous phase are unlikely to persist long enough to achieve meaningful treatment of slowly-desorbing PCBs associated with the soil phase. To investigate this explanation, laboratory studies were conducted to evaluate chemical reductants, including zero valent metals, palladium (Pd) catalyst, and emulsified zero valent iron (EZVI), for dechlorination of PCBs in the presence and absence of soil. In the absence of soil, Pd-catalyzed treatments (Pd with electrolytic ZVI or iron/aluminum alloy) achieved rapid destruction of a model PCB congener, 2-chlorobiphenyl, with half-lives ranging from 43 to 110 min. For treatment of soils containing Aroclor 1248 at an initial concentration of approximately 1,500 mg kg(-1), Pd-catalyzed treatments achieved no measurable enhancement over the background PCB depletion rate (i.e., that measured in the untreated control) of 5.3 mg kg(-1)week(-1). In the presence of soils, EZVI was the only approach evaluated that resulted in a clear enhancement in PCB dechlorination rates. EZVI achieved PCB concentration reductions of greater than 50% at an average rate of 19 mg kg(-1)week(-1). The results suggest that slow PCB desorption limits treatment effectiveness in soils.

Trophic organization and fish assemblage structure as disturbance indicators in headwater streams of lower Sorocaba River basin, São Paulo, Brazil

Studies that investigate the relationship patterns between environmental structure complexity and fish fauna provide crucial information to stream restoration efforts. In order to test the hypothesis that streams with more complex environmental structure sustain more diverse and functionally more complex fish communities we sampled fish fauna from Sorocaba River headwater stream reaches (SE - Brazil). Reaches represented two distinct treatments: (1) a simplified reach, characterized by unstable fine substrate, clay, deeper channel and higher water velocity and (2) structurally complex reaches, characterized by coarse substrate, with gravel, pebble, rock, stems and branches and leaves inside the channel, producing a diverse pattern of microhabitat, associated with sequences of pools, runs, and riffles. Both trophic structure and taxonomic composition varied significantly between treatments. Invertivorous trophic group exclusively occurred in structurally complex reaches, which also presented greater diversity and species richness. We suggest enhancing in-stream environmental structure that suffered simplification processes due to human impacts in order to reestablish fish communities and ecossistemic functioning. .

Estudos que buscam investigar os padrões de relação entre a complexidade da estrutura ambiental e a fauna de peixes fornecem informações cruciais para os esforços de restauração de riachos. Para testar a hipótese de que riachos com estrutura ambiental mais complexa sustentam comunidades ícticas mais diversas do ponto de vista taxonômico e funcional, a ictiofauna de trechos de riachos de cabeceira do rio Sorocaba (SE - Brasil) foi amostrada, representando dois tratamentos distintos: (1) um trecho de riacho simplificado, caracterizado por substrato fino e inconsolidado, composto por areia e silte, curso d'água mais profundo, com maior velocidade e poucos elementos diversificadores da estrutura de habitat e (2) trechos de riacho estruturalmente complexos, com substrato de fundo composto por elementos irregulares como cascalho, rochas, seixos, troncos, galhos e restos de madeira, produzindo um padrão diverso de microhabitats, associados à sequências de poços, corredeiras e trechos rápidos. Tanto a estrutura trófica quanto a composição taxonômica foram distintas em relação aos dois tipos de riachos. O grupo trófico dos invertívoros ocorreu somente nos trechos estruturalmente mais complexos, que apresentaram também maior diversidade e riqueza de espécies. Sugere-se incrementar a estrutura ambiental de riachos que sofreram simplificação ambiental, devido à ação humana, a fim de promover a reestruturação da comunidade íctica e o funcionamento ecossistêmico.

High performance liquid chromatography-tandem mass spectrometry method for quantifying phenylurea herbicides and their main metabolites in amended and unamended soils.

A sensitive multiresidue method for the simultaneous determination of sixteen phenylurea herbicides and their main metabolites in amended soils has been developed. Liquid chromatography tandem-mass spectrometry (LC-MS²) in electrospray ionization positive mode was used for the separation, identification and quantification of these compounds. The procedure involves initial single phase extraction of soil sample with acetonitrile by sonication, followed by liquid-liquid partitioning formed by addition of NaCl. The average recovery by the LC-MS² method obtained for these compounds varied from 76.2 to 107.9% with a relative standard deviation ranging from 2.1 to 5.8%. The method presents good linearity (R²>0.99) over the range assayed 10-1000 µg L⁻¹ (except N-phenylurea 50-1000 µg L⁻¹). The detection limits for the compounds studied varied from 0.1 to 9.0 ng g⁻¹.

Assays for the in vitro establishment of Swietenia macrophylla and Cedrela odorata / Ensayos para el establecimiento in vitro de Swietenia macrophyllay Cedrela odorata

Recalcitrance and contamination in Mahogany (Swietenia macrophylla King) and Spanish cedar (Cedrela odorata L.) stem tissues are the main causes of its ineffective in vitro propagation. The objectives of this research were: a) to evaluate sodium hypochlorite (NaOCl) and plant preservative mixture (PPM®) as surface disinfectants and/or added to the culture medium for the in vitro establishment of nodal explants taken from 10-year-old Mahogany and Spanish cedar plants, and b) to evaluate the in vitro response of such explants treated with N6-benzylaminopurine (BAP) (0, 2.2, 4.4, 8.8, 17.7 μM), silver nitrate (AgNO3) (0, 3 mg l-1), activated charcoal (0, 1 g l-1) and vented caps. All the experiments were arranged in a completely randomized design. The NaOCl at 15%, for 20 min, as a surface sterilization or PPM® at 2 ml l-1 into the culture medium, were the best treatments to reduce contamination for both species. For Mahogany explants, BAP at 17.7 μM resulted in higher percentages of bud breaks than Spanish cedar (64% and 25%, respectively). Leaves on elongated shoots dropped off by 20 days after starting the explants in culture and neither the activated charcoal nor the AgNO3 alone or combined prevented leaf abscission. The AgNO3 decreased contamination, but also increased leaf abscission. Bud breaks was two-fold higher for nodal explants established in vessels with vented caps than with normal caps. Mahogany nodal explants were easier to surface sterilize and more buds broke from BAP treated explants than Spanish cedar treated explants in the in vitro establishment.

La contaminación y la recalcitrancia de tejidos de tallo de Caoba (Swietenia macrophylla King) y Cedro español (Cedrela odorata L.) son las causas principales de su inefectiva micro-propagación. Los objetivos de la investigación fueron: a) evaluar el hipoclorito de sodio (NaClO) y una mezcal preservadora de plantas (PPM®) como desinfectantes superficiales y/o agregados al medio de cultivo para el establecimiento in vitro de explantes nodales de Caoba y Cedro español de 10 años de edad; b) evaluar la respuesta in vitro de tales explantes tratados con N6-benzylaminopurine (BAP) (0, 2.2, 4.4, 8.8, 17.7 μM), nitrato de plata (AgNO3) (0, 3 mg l-1), carbón activado (0, 1 g l-1) y tapas porosas. Los experimentos fueron establecidos bajo un diseño completamente al azar. La contaminación se redujo en ambas especies con NaOCl al 15% durante 20 min como desinfección superficial o con PPM® (2 ml l-1) agregado al medio de cultivo. El mayor porcentaje de brotación de explantes se obtuvo con BAP a 17.7 μM en caoba (64%) comparado con cedro (25%). Los brotes se defoliaron a los 20 días de cultivo y ni el carbón activado ni el AgNO3, solos o combinados evitaron la defoliación. El AgNO3 disminuyó la contaminación, pero incrementó la defoliación. La brotación fue dos veces mayor en los explantes nodales establecidos en recipientes con tapas porosas que cuando se utilizaron tapas normales. Los explantes nodales de Caoba respondieron mejor a la desinfección superficial y a los tratamientos de BAP comparados con los de Cedro español en el establecimiento in vitro.

Global scenarios of air pollutant emissions from road transport through to 2050.

This paper presents global scenarios of sulphur dioxide (SO(2)), nitrogen oxides (NO(x)), and particulate matter (PM) emissions from road transport through to 2050, taking into account the potential impacts of: (1) the timing of air pollutant emission regulation implementation in developing countries; (2) global CO(2) mitigation policy implementation; and (3) vehicle cost assumptions, on study results. This is done by using a global energy system model treating the transport sector in detail. The major conclusions are the following. First, as long as non-developed countries adopt the same vehicle emission standards as in developed countries within a 30-year lag, global emissions of SO(2), NO(x), and PM from road vehicles decrease substantially over time. Second, light-duty vehicles and heavy-duty trucks make a large and increasing contribution to future global emissions of SO(2), NO(x), and PM from road vehicles. Third, the timing of air pollutant emission regulation implementation in developing countries has a large impact on future global emissions of SO(2), NO(x), and PM from road vehicles, whereas there is a possibility that global CO(2) mitigation policy implementation has a comparatively small impact on them.

Lead and copper in pigeons (Columbia livia) exposed to a small arms-range soil.

Small arms-range (SAR) soils can be contaminated with metals from spent copper (Cu)-jacketed bullets. Avian species are particularly at risk because they are exposed to lead (Pb) through ingestion of grit, soil intake from preening, or ingestion of contaminated food near ranges. Examination of the effects of Pb on birds at ranges have mainly focused on intake and toxicity of Pb shot pellets or fragments; however, Pb in soils may be an important pathway of exposure. To evaluate the uptake and effects of Pb from an actual range, the soil fraction (<250 µm) from a contaminated SAR soil was used to dose pigeons (Columbia livia) for 14 days at low (2700 µg Pb and 215 µg Cu/d) and high (5400 µg Pb and 430 µg Cu/d) doses. At the end of the study, blood Pb and erythrocyte protoporphyrin were determined, and tissues were analyzed for Pb and Cu. Results showed that Pb was absorbed in a dose-response manner in blood, tissues, and feathers, and erythrocyte protoporphyrin, a biomarker of early Pb effect, was increased at blood Pb levels >50 µg/dL. Four tissues showed differential retention of Pb, with kidney having the highest concentration followed by liver, brain, and heart, whereas Cu levels were not changed. To examine possible interactions with other metals, amendments of either Cu or tungstate were made to the soil sample. Although these amendments seemed to decrease the absorption of Pb, the results were ambiguous compared with sodium chloride controls. Overall, this study showed that intake of SAR soils contaminated with Pb and Cu causes an increase in Pb body burdens in birds and that the response can be modulated by amending soils with salts of metals.

Arbóreas medicinais das matas ciliares do Rio Canoas: potencialidade de uso em projetos de restauração / Medicinal trees from riparian forests along Canoas River: potential use in restoration projects

Este estudo objetivou identificar as espécies arbóreas medicinais das matas ciliares de três pequenas propriedades rurais do município de Urubici-SC, e estabelecer relações entre as características ecológicas das mesmas com as possibilidades de emprego para restauração de ambientes ciliares degradados. Empregou-se o método dos quadrantes, para levantamento dos indivíduos com CAP>15 cm. Os indivíduos amostrados foram herborizados, depositados no Herbário LUSC e categorizados quanto ao uso medicinal, parte usada, freqüência, síndrome de dispersão (anemocórica, autocórica e zoocórica), grupo ecológico (pioneira, secundária inicial, secundária tardia) e uso para restauração florestal. Dos 240 indivíduos amostrados, 197 indivíduos pertencentes a 22 espécies de 15 famílias botânicas apresentaram potencialidades medicinais. As famílias Euphorbiaceae, Rosaceae, Myrtaceae, Sapindaceae, Lauraceae e Anacardiaceae foram as mais abundantes. Mais de 85 por cento das espécies com potencial medicinal amostradas apresentaram síndrome de dispersão zoocórica; cerca de 78 por cento foram incluídas nos grupos ecológicos das secundárias iniciais e pioneiras e cerca de 88 por cento são recomendadas para restauração. As espécies arbóreas medicinais são bastante freqüentes nas matas ciliares degradadas do Rio Canoas, podendo ser fonte de recursos genéticos para a restauração e adequação das APPs à legislação ambiental, além de se constituírem em produtos florestais não madeireiros passíveis de exploração.

This study aimed to identify the medicinal arboreal species from riparian forests at three small farms in Urubici Municipality, Santa Catarina State, Brazil, and relate their ecological features to the possibilities of their use for restoration of degraded riparian environments. In order to survey individuals with circumference at breast height (CBH) >15 cm, the quadrant method was adopted. The sampled specimens were herborized, incorporated into the Herbarium LUSC and categorized according to their medicinal use, employed part, frequency, dispersal syndrome (anemochory, autochory and zoochory), ecological group (pioneer, early secondary, late secondary) and use for forest restoration. Of the 240 sampled specimens, 197 belonging to 22 species of 15 families were potentially medicinal. The most abundant families were Euphorbiaceae, Rosaceae, Myrtaceae, Sapindaceae, Lauraceae and Anacardiaceae. More than 85 percent potentially medicinal species had zoochoric dispersal syndrome, around 78 percent were categorized as early secondary and pioneer, and around 88 percent were recommended for restoration. Medicinal arboreal species are quite common in degraded riparian forests along Canoas River. They can provide genetic resources for restoration and adequacy of permanent preservation areas (PPAs) to the environmental legislation; moreover, they are exploitable non-timber forest products.

[Ecotoxicological value of sediments state from reservoir R-11 of Techa River reservoir cascade].

Researches of sediments state from reservoir R-11 of tandem Techa river reservoir cascade were made. Shershni (Shershni's reservoir, Chelyabinsk region) was used as reference reservoir. Radiochemical analysis of sediments and water from those reservoirs were made (radioactivity in sediments of R-11 ranged from 240 to 360 kBq/kg of dry weight for 90Sr and from 10 to 161 kBq/kg of dry weight for 137Cs). Hydrobiological researches were included (1) detection of quantitative progress and species composition of Oligochaeta fauna in reservoirs and (2) bioassay of sediments in laboratory conditions with using test-organisms Tubifex culture. Calculation of absorbed dose for Oligochaeta from reservoir R-11 was performed on basis of radiochemical analysis data. Our results indicated that quantitative progress of Oligochaeta in reservoir R-11 was less then progress in Shershni's reservoir. R-11 sediments bioassay did not show any toxic effect by tubificidae in laboratory experiments. Significant dependence for quantitative progress Oligochaeta in reservoir R-11, survival rate and breeding power from absorbed dose rate weren't found. However in subacute research breeding power for animals with higher radiation (absorbed) dose was reduced.

Acute health problems related to the operation mounted to clean the Hebei Spirit oil spill in Taean, Korea.

The authors investigated acute health problems in people engaged in the operation mounted to clear the Hebei Spirit oil spill which occurred in December 2007 in Taean County, South Korea, and identified the risk factors associated with the development of symptoms. Eight hundred forty-six people engaged in the clean up operation for periods between 7 and 14 days were examined. Demographic information and risk factors were obtained using a questionnaire. Symptoms were classified into six categories: back pain, skin lesions, headache, and eye, neurovestibular, and respiratory symptoms. Residents and volunteers engaged in the Hebei Spirit oil spill clean up operation experienced acute health problems. Risk analyses revealed that more frequent and greater exposure was strongly associated with a higher occurrence of symptoms.

Attenuation of hydrogen sulfide at construction and demolition debris landfills using alternative cover materials.

The attenuation of H(2)S emissions by various landfill cover materials was evaluated using both laboratory and field experiments. The results demonstrated that cover materials consisting of selected waste products (compost and yard trash) and soils amended with quicklime and calcium carbonate effectively attenuated H(2)S emissions and detectable H(2)S emissions were only encountered in a testing plot using a sandy soil cover (average emission rate was 4.67x10(-6)mgm(-2)s(-1)). H(2)S concentration profiles in the cover materials indicated that H(2)S was removed as it migrated through the cover materials. At the same depth in the testing area, the H(2)S concentration in the sandy soil field plot was always higher than that of other testing plots because the sand (a) demonstrated less ability to remove H(2)S and (b) exhibited a higher H(2)S concentration at the base of the cover. Laboratory experiments confirmed these observations, with a combination of physical adsorption, chemical reactions, and biological oxidation, accounting for the enhanced removal. In addition to removal, the results suggest that some of the cover materials reduced H(2)S generation by creating less favorable conditions for sulfate-reducing bacteria (e.g., high pH and temperature).

The ecohealth assessment and ecological restoration division of urban water system in Beijing.

Evaluating six main rivers and six lakes in Beihuan water system (BWS) and diagnosing the limiting factors of eco-health were conducted for the ecohealth assessment and ecological restoration division of urban water system (UWS) for Beijing. The results indicated that Jingmi River and Nanchang River were in a healthy state, the degree of membership to unhealthy were 0.358, 0.392, respectively; while Yongding River, Beihucheng River, Liangma River, Tongzi River and six lakes were in an unhealthy state, their degree of membership to unhealthy were between 0.459 and 0.927. The order of that was Liangma > Beihucheng > Tongzi > Yongding > six lakes > Jingmi > Nanchang, in which Liangma Rivers of that was over 0.8. The problems of Rivers and lakes in BWS are different. Jingmi River and Nanchang River were ecotype limiting; Yongding River, Tongzi River and six lakes were water quality and ecotype limiting. Beihucheng River and Liangma River were water quantity, water quality and ecotype limiting. BWS could be divided into 3 restoration divisions, pollution control division including Yongding River, Tongzi River and six lakes; Jingmi River and Nanchang River were ecological restoration zone, while Beihucheng River and Liangma River were in comprehensive improvement zone. Restoration potentiality of Jingmi River and Nanchang River were higher, and Liangma River was hardest to restore. The results suggest a new idea to evaluate the impact of human and environmental factors on UWS.

Personal and static sample measurements of asbestos fibres during two abatement projects.

Exposure assessment was performed during the abatement of amosite containing material (ACM) and chrysotile containing material (CCM). Mean fibre concentrations (MFC) in breathing zone (BZ) were 20.6+/-7.9 f/cc and 6.3+/-2.2 f/cc during abatements of ACM and CCM, respectively. At the fixed station, MFC were 5.4+/-3.5 f/cc for ACM and 2.9 f/cc+/-1.6 for CCM. For observer's BZ, MFC were 3.1+/-1.3 f/cc (ACM) and 1.8 f/cc (CCM) during the abatement. Though elevated, area and observer-type samples clearly underestimate exposure. Exposure remained unacceptable in the worksite with the class of respiratory protection used.

Remediation measures and displacement of pollutants in soils affected by the spill of a pyrite mine.

The soils affected by the spill of a pyrite mine were analysed in 100 sampling points at three depths (0-10, 10-30, and 30-50 cm) in 1998 (after the tailings were removed), 1999 (after the cleaning of the highly contaminated areas), and 2004 (after the tilling of the upper 20-25 cm). The comparative study reveals that the removal of the tailings left a heterogeneous distribution pattern of the contaminants, with highly polluted spots alternating with less contaminated areas. The cleanup did not substantially lower the concentration in the highly polluted soils, and the spread of the pollutants increased the concentration in As and Pb in the uppermost 10 cm of 60% of the soils, while the Zn and Cd concentrations increased in only 30% of the soils. Given the high concentration of pollutants in the topsoil (especially As), the tilling of the upper 20-25 cm, despite reducing the average concentration of pollutants in the uppermost 10 cm, did not substantially lower the percentage of soils that exceeded the concentration of 40 mg As kg(-1) dry soil and almost doubled the percentage of soils that surpassed this concentration between 10 and 30 cm. Meanwhile, the displacement of Zn and Cd within the soil supported the reduction in the percentage of soils that in the upper 10 cm exceeded the reference concentrations of these elements (900 mg Zn kg(-1) dry soil and 2 mg Cd kg(-1) dry soil), and the percentage of soils exceeding these concentrations between 10 and 50 cm in depth did not increase. Six years after the spill and at the end of all remediation measures, the intervention levels defined by the Environmental Agency of the Regional Government of Andalusia for natural parks were exceeded in the uppermost 10 cm in 35% of the soils.

Soil suspension/dispersion modeling methods for estimating health-based soil cleanup levels of hexavalent chromium at chromite ore processing residue sites.

The primary health concern associated with exposures to chromite ore processing residue (COPR)-affected soils is inhalation of hexavalent chromium [Cr(VI)] particulates. Site-specific soil alternative remediation standards (ARSs) are set using soil suspension and dispersion models to be protective of the theoretical excess cancer risk associated with inhalation of soil suspended by vehicle traffic and wind. The purpose of this study was to update a previous model comparison study that identified the 1995 AP-42 particulate emission model for vehicle traffic over unpaved roads and the Fugitive Dust Model (FDM) as the most appropriate model combination for estimating site-specific ARSs. Because the AP-42 model has been revised, we have updated our past evaluation. Specifically, the 2006 AP-42 particulate emissions model; the Industrial Source Complex-Short Term model, version 3 (ISCST3); and the American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) air dispersion models were evaluated, and the results were compared with those from the previously used modeling approaches. Two sites with and two sites without vehicle traffic were evaluated to determine if wind erosion is a significant source of emissions. For the two sites with vehicle traffic, both FDM and ISCST3 produced total suspended particulate (TSP) estimates that were, on average, within a factor of 2 of measured; whereas AERMOD produced estimates that were as much as 5-fold higher than measured. In general, the estimated TSP concentrations for FDM were higher than those for ISCST3. For airborne Cr(VI), the ISCST3 model produced estimates that were only 2- to 8-fold of the measured concentrations, and both FDM and AERMOD estimated airborne Cr(VI) concentrations that were approximately 4- to 14-fold higher than measured. Results using the 1995 AP-42 model were closer to measured than those from the 2006 AP-42 model. Wind erosion was an insignificant contributor to particulate emissions at COPR sites.

Research for deployment: incorporating risk, regulation, and liability for carbon capture and sequestration.

Carbon capture and sequestration (CCS) has the potential to enable deep reductions in global carbon dioxide (CO2) emissions, however this promise can only be fulfilled with large-scale deployment. For this to happen, CCS must be successfully embedded into a larger legal and regulatory context, and any potential risks must be effectively managed. We developed a list of outstanding research and technical questions driven by the demands of the regulatory and legal systems for the geologic sequestration (GS) component of CCS. We then looked at case studies that bound uncertainty within two of the research themes that emerge. These case studies, on surface leakage from abandoned wells and groundwater quality impacts from metals mobilization, illustrate how research can inform decision makers on issues of policy, regulatory need, and legal considerations. A central challenge is to ensure that the research program supports development of general regulatory and legal frameworks, and also the development of geological, geophysical, geochemical, and modeling methods necessary for effective GS site monitoring and verification (M&V) protocols, as well as mitigation and remediation plans. If large-scale deployment of GS is to occur in a manner that adequately protects human and ecological health and does not discourage private investment, strengthening the scientific underpinnings of regulatory and legal decision-making is crucial.

Determination of acidic pharmaceuticals and potential endocrine disrupting compounds in wastewaters and spring waters by selective elution and analysis by gas chromatography-mass spectrometry.

Although the trend in development of analytical methods for emerging contaminants is towards reduced sample preparation and increased detector selectivity, there are still benefits from removal of matrix material during sample preparation. This paper describes a simple method for acidic pharmaceuticals and a range of potential endocrine disrupting compounds in untreated wastewaters and spring waters. It is based on separation of the two classes during elution from the extraction cartridge with final analysis by gas chromatography-mass spectrometry. 3,4-D was used as the recovery standard for the acids while 4-n-nonylphenol and [2H4]estrone were used for the endocrine disrupters; mean recoveries varied between 89% and 111%. The method was also extensively validated by fortification with the target compounds. Recoveries of acids were from 68% to 97% with relative standard deviations generally less than 10% and recoveries of endocrine disrupters were 68-109% with relative standard deviations less than 20%. Detection limits varied from 0.005 to 1 ng/L in spring water, and from 0.5 to 100 ng/L in untreated wastewater. Concentrations of the analytes in the wastewater ranged from 0.018 to 22.4 microg/L. Values were comparable to reported data, although concentrations were generally relatively high, probably because of a lack of treatment. Triclosan, phthalates, estrone, 17beta-estradiol, ibuprofen, and naproxen were present in the spring water from aquifers recharged indirectly with this wastewater after its use for irrigation; concentrations ranged from 0.01 to 25.0 ng/L. The much lower concentrations compared to wastewater indicate effective removal processes on passage through the soil and subsoil.

Recovery assessment of a refined-oil impacted and fire ravaged mangrove ecosystem.

An assessment of the diversity and abundance of macrobenthic community in a refined-oil (petrol) impacted and fire-ravaged mangrove ecosystem within the vicinity of a marine receipt terminal facility (Atlas Cove) serving as a distribution and pump station for refined products was carried out. The mangrove ecosystem was subjected to massive petrol spillage from a leaking pipeline and eventual fire outbreak. Following rehabilitation activities, a recovery assessment of the impacted ecosystem was carried out. The field surveys revealed that the petrol leakage and fire outbreak resulted in a near complete destruction of the mangrove ecosystem around the Atlas Cove depot, with macrobenthic species diversity index ranging between 0-0.4, compared to 0.78-0.87 in the control stations. The dominant early arrivals or colonizers of the impacted stations areas were Clibanarius africanus and Callinectes amnicola. Early signs of recovery of the impacted area were observed within about two and a half (2 1/2) to three (3) months, based on diversity and abundance indices respectively. The period of early signs of recovery also coincide with an observed reduction in the total hydrocarbon content (THC) levels in the sediment collected from the impacted stations by about nine folds from 3.67 mg/kg to 0.42 mg/kg within 3 months. Despite the apparent signs of recovery, the need for long-term monitoring of the impacted stations was discussed.