Raw sugarcane bagasse as carbon source for xylanase production by Paenibacillus species: a potential degrader of agricultural wastes

Environmental Science and Pollution Research - Paenibacillus species isolated from a variety of natural sources have shown to be important glycoside hydrolases producers. These enzymes play a key...     

Effects of Mowing and Prescribed Fire on Plant Community Structure and Function in Rare Coastal Sandplains,Nantucket Island,MA, USA

Coastal sandplains provide habitat for a suite of rare and endangered plant and wildlife species in the northeastern United States. These early successional plant communities were maintained by natural and anthropogenic disturbances including salt spray, fire, and livestock grazing, but over the last 150 years, a decrease in anthropogenic disturbance frequency and intensity has resulted in a shift towards woody shrub dominance at the expense of herbaceous taxa. This study quantified the effects of more than a decade of dormant season disturbance-based vegetation management (mowing and prescribed fire) on coastal sandplain plant community composition on Nantucket Island, Massachusetts, USA. We used time-series plant cover data from two similar sites to evaluate the effectiveness of disturbance management for restoring herbaceous species cover and reducing woody shrub dominance. Our results indicate that applying management outside of the peak of the growing season has not been effective in maintaining or increasing the cover of herbaceous species. While management activities resulted in significant (P < 0.01) increases in herbaceous species immediately after treatment, woody species recolonized and dominated treated sites within 3-years post treatment at the expense of graminoids and forbs. These results highlight the difficulties associated with directing ecological succession using disturbance-based management to maintain rare, herbaceous species in coastal sandplain systems that were once a prevalent landscape component under historically chronic anthropogenic disturbance. Further experimentation with growing season disturbance-based management and different combinations of management techniques could provide insights into management alternatives for maintaining herbaceous conservation targets in coastal sandplains.     

Impact of harmful algal blooms on wild and cultured animals in the Gulf of California

Historical documents and classic works together with recent specialized literature have described Harmful Algal Blooms (HABs) in the Gulf of California. This is a review of HABs impact (qualitative and quantitative) during the last decades in the Gulf of California on wild (mammals, birds, fishes, and invertebrates) and cultured animals (shrimps and fishes). Microalgal species responsible of noxious effects are Noctiluca scintillans, Cochlodinium polykrikoides, Gymnodinium catenatum, Prorocentrum minimum, Akashiwo sanguinea, Chattonella subsalsa Ch. marina, Chattonella sp., Heterocapsa sp., Dinophysis sp., Fibrocapsa japonica, Heterosigma akashiwo, Thalassiosira sp., Chaetoceros spp., Pseudo-nitzschia australis, P fraudulenta, Pseudo-nitzschia sp., Trichodesmium erythraeum and ScSchizotrix calcicola. Emphasis is given to the necessity to continue with interdisciplinary studies in oceanography, ecology, toxicology and toxinology interrelated with biomedical sciences such as physiology, pathology, epidemiology and animal health.     

Identification of Enterococcus faecalis bacteria resistant to heavy metals and antibiotics in surface waters of the Mololoa River in Tepic, Nayarit, Mexico

Heavy metal and antibiotic resistance have been shown to have a strong correlation in nature, and their inter-relation is an important subject of study. We report an analysis of surface waters of the Mololoa River in the municipality of Tepic, state of Nayarit, Mexico. This river has two distinctive sources of contamination: sewage waters and trash confinements. Our findings demonstrate a correlation between the river flow pattern and resistance to heavy metals or to heavy metals and antibiotics in isolated bacteria of the genus Enterococcus, specifically Enterococcus faecalis. The Mololoa River provides a model to study the relationship between water flow and generation of biodiversity, and more importantly, it constitutes a model for studying genetic diversity of bacteria affecting human health.     

A conceptual model of the role of complex science in local authority consultations about air quality management

Abstract

There exists a clear imperative across the EU and within the UK towards the enhanced integration of community knowledge in environmental and health decision-making processes. The underlying social force that underpins this dynamic is the drive for a more accountable, transparent and publicly acceptable decision-making arena. However, relatively little research has been undertaken on the evaluation of local air quality management consultation in particular. In this context, the paper presents an evaluation of evidence resulting from questionnaire survey and case study research undertaken in the first round of the statutory process of local air quality management (LAQM), in which local authorities are required to consult on their air quality findings and intentions. We suggest that local authority perceptions of the relative abilities of differing stakeholders' grasp of air quality science, the process that translates that science into policy, and the institutional and organizational status of stakeholders (i.e. whether they are statutory or non-statutory stakeholders) may tend to transitively determine the choice of consultation methods used, the communication strategies chosen and the relative integration of stakeholder feedback into the LAQM decision-making process. In order to interrogate this potentially problematic chain of risk communication events, a preliminary conceptual model has been developed to enable the interrogation of the pathways through, and the obstacles to, the translation of air quality knowledge. The task is to unveil the sequential chains of association that comprise the LAQM risk communication process.     

Contamination Levels and Preliminary Assessment of the Technical Feasibility of Employing Natural Attenuation in 5 Priority Areas of Presidente Bernardes Refinery in Cubatão, São Paulo, Brazil

Five priority areas of potential impact by contaminants (API) were investigated at the Presidente Bernardes Refinery in Cubatão, São Paulo, Brazil with the following aims: (i) to identify both organic and inorganic contaminants present in soil and groundwater; (ii) to define the environmental conditions relevant for microbial activity at the site and (iii) to evaluate the feasibility of employing natural attenuation for treatment of the hydrocarbon contamination. One area (API 1) was an uncontrolled landfill, where waste materials from the refinery were deposited between 1954 and 1986, and four areas (API 4, 5, 7 and 11) were located in the operational section of the refinery. Soil contamination by regulated BTEX compounds (benzene, toluene, total xylenes) was restricted to two samples from API 1. Nonregulated ethylbenzene was detected in one soil sample from API 4, one from API 5 and two from API 1. No soil contained regulated PAH above threshold levels. Several nonregulated PAHs were found in 6 soil samples from API 1, 3 soil samples from API 4 and 1 soil sample from API 5. Site soils contained very high aluminium concentrations, but metal contamination was restricted to one soil sample from API 1, which contained nickel above threshold limits. BTEX contamination of groundwater was due mostly to benzene. Of the 17 PAH molecules tested, only naphthalene and 2-methylnaphthalene occurred in groundwater. The sum of total BTEX and total PAH exceeded 200 μg/L in only a few monitoring wells in API 4, 5 and 11 and was always below 2.640 μg/L. Be, Cd, Cr, Cu, Hg, Ni, Se, Ag, Tl and Zn were not detected in groundwater, which was contaminated in a few locations by aluminium (mostly below 1 mg/L), lead (<0.066 mg/L) and arsenic (<0.056 mg/L). S, K, Ca, Mg and Fe were present in groundwater in excess of physiological requirements for microbial growth, but low concentrations of N and P could become growth limiting. However, BTEX were efficiently degraded in saturated and unsaturated zone microcosms and nutrient amendments did not stimulate biodegradation rates measurably. The inorganic carbon pool in groundwater was up to one order of magnitude larger than the organic carbon pool. Total inorganic carbon (TIC) in API groundwater exceeded TIC of clean groundwater by factors of 2 (API 4), 6 (API 5, 7 and 11) or 10 (API 1). Most of the inorganic carbon incorporated into groundwater beneath the refinery originated from biodegradation in the unsaturated soil, which contained a microbiota (10⁶ cells/g on average) capable of growth with most of the pure (benzene, toluene, ethylbenzene and xylene) and mixed hydrocarbons tested (diesel oil, gasoline, naphtha, condensate, aromatic residue and fuel oil). A viscous hydrocarbon paste uncovered in API 1 was insoluble in water but dissolved in dichloromethane. Many organic components of this paste were biodegradable as evidenced by weight reduction of the hydrocarbon paste and by the growth of suspended and attached biomass in saturated zone microcosms, where the paste was the only carbon source. This study indicates that monitored natural attenuation may be a technically feasible and efficient means for plume control in API 1, 4 and 5, provided the plumes in API 4 and 5 are not expanding. This technique is not suitable for contaminant reduction in API 11.     

Adsorption behavior of 2,4-dichlorophenol and pentachlorophenol in an allophanic soil

The adsorption of 2,4-dichlorophenol (2,4-DCP) and pentachlorophenol (PCP) by a variable-charge soil from southern Chile was studied in a series of batch equilibration experiments. 2,4-DCP and PCP adsorption behavior was evaluated as a function of pH (pH values of 4.5, 6.0 and 7.5) in a 0.1M KCl (25 degrees C) background solution for soil material collected at three different depths (0-20 cm, 20-40 cm, and 40-60 cm). 2,4-DCP and PCP adsorption decreased with increasing soil pH, suggesting that the undissociated species were adsorbed more readily and that electrostatic repulsion may inhibit partitioning as pH increases. The PCP adsorption was greater than observed for 2,4-DCP and decreased with soil depth. Multiple regression analysis between K(d) and various soil properties indicated that the soil organic carbon content is a strong indicator of chlorophenol adsorption, and in addition to organic carbon, the soil pH is an important property controlling adsorption behavior.     

Expediting sustainable brownfields redevelopment by applying Triad using the membrane interface probe

Redevelopment and reuse plans are often based upon an expedited delineation and remediation life cycle, since delayed reuse usually has economic consequences. It has also become increasingly important to utilize sustainable practices to achieve investigation and remediation goals. In this article, the Triad approach is used to expedite the delineation of a source area within a municipal landfill to complete the remedial effort prior to construction of an urban civic center. The Triad approach uses the three elements of systematic project planning, dynamic work strategy, and real‐time measurement to expedite site characterization (Interstate Technology and Regulatory Council, 2003). In this article, the Triad sampling strategy consisted of two phases. The first phase included in situ screening of soil and groundwater using the membrane interface probe (MIP), and the second phase included confirmatory sampling via vertical profiles in the soil and groundwater. This study found that, using the MIP in a dynamic sampling strategy, a critical element of the Triad approach, combined with the proper placement of confirmatory samples, significantly reduced overall project cost and will expedite the site redevelopment. The use of the Triad approach also contributed to the integration of green and sustainable practices into the project. © 2010 Wiley Periodicals, Inc.     

Judging the Risk of Exceedance: Local authority decision-making for air quality management area designation

Management of air quality by local government in the United Kingdom (England, Scotland, Wales and Northern Ireland) requires a process of local decision-making, involving collaboration between local politicians, authority officers and interest-groups. Since the establishment of the first National Air Quality Strategy for the UK in 1997, local authority environmental health professionals have undertaken a scientific review and assessment process to identify locations where predicted future pollutant concentrations may exceed national air quality objectives. Air quality management areas (AQMAs) are declared where such exceedences are predicted. Over recent years, significant changes in local authority decision-making structures in England, Scotland and Wales have occurred, resulting in changes to the structure and governance in many local authorities. Results are presented from local authority surveys undertaken to examine the occurrence of any conflicts between the science involved in predicting exceedences and the local political decision-making processes in declaring AQMAs. Data are presented for a sample set of local authorities in Great Britain from which it is concluded that decision-making structures in local government are having a demonstrable impact on the designation of AQMAs.