Effect of salinity on community structure and naphthalene dioxygenase gene diversity of a halophilic bacterial consortium

The aim of this study is to analyze the effect of salinity on polycyclic aromatic hydrocarbons (PAHs) biodegradation, community structure and naphthalene dioxygenase gene (ndo) diversity of a halophilic bacterial consortium with the denaturing gradient gel electrophoresis (DGGE) approach. The consortium was developed from oil-contaminated saline soil after enrichment for six times, using phenanthrene as the substrate. The prominent species in the bacterial consortium at all salinities were identified as halophilic bacteria Halomonas, Alcanivorax, Marinobacter, Idiomarina, Martelella and uncultured bacteria. The predominant microbes gradually changed associating with the saline concentration fluctuations ranging from 0.1% to 25% (w/v). Two ndo alpha subunits were dominant at salinities ranging from 0.1% to 20%, while not been clearly detected at 25% salinity. Consistently, the biodegradation occurred at salinities ranging from 0.1% to 20%, while no at 25% salinity, suggesting the two ndo genes played an important role in the degradation. The phylogenetic analysis revealed that both of the two ndo alpha subunits were related to the classic nah-like gene from Pseudomonas stutzeri AN10 and Pseudomonas aeruginosa PaK1, while one with identity of about 82% and the other one with identity of 90% at amino acid sequence level. We concluded that salinity greatly affected halophilic bacterial community structure and also the functional genes which were more related to biodegradation.

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Vertical growth in a coastal city: an analysis of Boa Viagem (Recife,Brazil)

Coastal zones around the world have experienced urban growth in the last 50 years. This landscape change brings new aspects for those zones and the environment. Real estate speculation is a decisive factor that changes landscape, with urban growth that occurs both in the extent and volume of construction. Boa Viagem (BV) beach at Recife, Northeast Brazil was just a sand bar covered by an Atlantic Forest until middle of the 1800s. Today, it has turned into a busy area of the city where residences, services and commerce co-exist in a densely packed arrangement. This work demonstrates and analyses vertical growth in BV and urban changes from 1961 to 2011. It was developed using digital image processing and visual analysis of satellite imagery and aerial photos. A GIS was created using SPRING and ArcScene, to calculate variations in area and volume creating a Volumetric Index (VI). The Minimal Mapping Area was used in sixteen census tract as samples of the area. Occupation and vertical growth were especially accentuated from 1981 to 1996 with the peak at 2011. Increases in vertical growth from shore to inland are evident in all parts of the district. This finding was confirmed by three-dimensional GIS representations of the study area and the VI during the period of this work, showing the potential of 3D GIS models for studying dense urbanization areas in coastal zones.     

Shoreline shifting and its prediction using remote sensing and GIS techniques: a case study of Sagar Island,West Bengal (India)

The shoreline position is difficult to predict but the trend of erosion or accretion can be determined by geospatial and statistical techniques which may help in reducing the loss of property. The study aims to assess the shoreline changes and prediction in Sagar Island, a delta of the Ganges, situated in West Bengal, India. Shorelines have been delineated by using Tasseled Cap Transformation techniques from the Landsat MSS (1975), Landsat TM (1989, 1991) and Landsat ETM+ (1999, 2002, 2005, 2008, and 2011) images. The uncertainty was calculated for every year for assessing the positional error related to shoreline extraction. Total shoreline change rate/year has also been calculated and the uncertainty of total shoreline change rate was found ±3.20 m/year. In the present study, End Point Rate (EPR) and Linear Regression (LR) methods have been used for shoreline change rate calculation and prediction of shoreline. Long term (1975–2002) and short term (2002–2011) erosion and accretion rates were calculated for the study area. Sagar is the biggest island of the Sundarban region; so, it was divided into three segments in order to analyze the change on a segment basis. It was observed that the most of erosion occurred in the Segment B (south Sagar). The rate of erosion was ?7.91 and ?7.01 m/year for the periods 1975–2002 and 2002–2011 respectively. The mean shoreline change rate was high in Segment B (South Sagar) with values of ?6.46 m/year (1975–2002) but the rate was decreased into ?5.25 m/year during the later period (2002–2011). The study reveals that most of the southern part of Sagar Island is vulnerable to high rate of shoreline erosion.     

Jellyfish jelly press and jelly perception

Since the early 2000’s, invasions and blooms of jellyfish have been increasingly reported in scientific literature as well as in the general media. Despite this increased coverage, the global jellification issue remains unsolved due to the scarcity of extended time series. The aim of this study was to determine to what extent the main messages about jellyfish (increase, causes, threats, solutions, etc.) in the Flemish (Belgian Dutch-language) media correspond with the knowledge and perception of recreational users, tourism-related professionals and local government officials on the Belgian coast. The number of articles in the Flemish media (140) increased from <5 in 2000 to 27 in 2010, with half of them reporting on jellyfish in the Belgian Part of the North Sea. Almost 75 % of these articles reported on the causes (overfishing being mentioned as the main cause) and economic consequences of jellyfish blooms. Articles about the dramatic consequences of stinging, poisonous and non-indigenous species were also common. A questionnaire-based survey carried out on the Belgian coast in summer 2012 indicated that jelly perception is only partly driven by the general media, while personal experience seemed at least equally important as driver. Information on causes, threats, consequences and solutions for problems caused by jellyfish corresponded to a large extent with the answers given by recreational users and tourism-related professionals. Respondents generally agreed that all underlying causes of a potential jellification problem should be addressed and tackled at an international level. With keywords like “pain”, “smell” and “slime” used to describe jellyfish, they have little sympathy from most actors, and most recreational users of beaches and coastal waters are extremely careful with any type of jellyfish, especially when children are involved. Species-specific knowledge (names, ecology, stinging vs. harmless species) presented in the media is not assimilated by most recreational users or local officials, except for divers, who have a very different perception of jellyfish than most recreational users. This lack of knowledge appeared to be a key issue in perception among recreational users. As public perception is a key driver in policy decisions, integrated coastal zone management and measures should provide good and easily understandable information, for example by distributing leaflets and putting up warning signs on the beach. This will result in a better understanding and acceptance of jellyfish as well as generating high-quality data from citizen science programs. Better and more information on jellyfish will thus benefit all the actors and sectors potentially affected by jellification.     

Rates of spread of <Emphasis Type="Italic">Rosa rugosa</Emphasis> (Japanese Rose) determined by GIS on a coastal sand-dune system in Northwest England

The invasive non-native shrub Rosa rugosa (Japanese Rose) is well-established in many northwest European countries where, especially on coastal sand-dunes, it forms large dominant stands with adverse effects on semi-natural vegetation and biota of high conservation status. Its recent increase in England’s largest dune system on the Sefton Coast in north Merseyside led to an investigation into its rate of spread. Using digitised aerial photographs and GIS methodology, sample patches of old-established R. rugosa were found to have grown in area by an average of 22 % per annum between 1989 and 2013. This rate of increase is comparable to that found in Denmark and higher than reported for several other woody plants in coastal dunes. In the absence of management, R. rugosa could soon dominate large areas on the Sefton Coast, with serious consequences for amenity and the nature conservation interest of the dune system.     

Measurements of fog water interception by shrubs on the California central coast

Fog water deposition may be an important component of the water budget of herbaceous-shrub ecosystems on the central and southern coastal regions of California. This paper presents the first analysis of measured fog water drip rates and meteorological controls in shrublands of Big Sur, California. Seasonal totals of 1255 mm and 306 mm of fog water drip were recorded in 2014 and 2015 (respectively), for averaged fog deposition rates of 0.02–0.08 l m² hr.^?1 to the soil under shrub canopy cover. The diurnal patterns of fog water drip showed that the majority of all trough water collected under shrubs on no-rain days occurred between the hours of 11 PM and 9 AM. During the study period from June 1 to October 31 of both 2014 and 2015, soil water content decreased significantly from average levels of 4–6 % at the shrub canopy center and middle locations, through 2–3 % VWC at the shrub edge locations, to levels at or below 2 % at 2-m distance locations from the shrub edge in open grass cover. Based on these results, we conclude that detectable rates of shrub canopy fog interception help sustain elevated soil water levels under shrubs and aid woody vegetation survival through periods of low rainfall.     

Biodegradation of N,N-bis(carboxymethyl)-L-glutamate and its utilization as sole source of carbon,nitrogen, and energy by a Rhizobium radiobacter strain in seawater

Biodegradation of N,N-bis(carboxymethyl)-L-glutamate and its utilization by micro-organisms in marine environments were studied in Organization of Economic Development and Cooperation (OECD) screening tests and with pure bacterial cultures. Biodegradation in excess of 60% was achieved in closed bottle tests in less than 60 days, suggesting complete degradation. The bacterial strain isolated from marine sandy sediment and utilizing N,N-bis(carboxymethyl)-L-glutamate as sole source of carbon, nitrogen, and energy was identified as Rhizobium radiobacter. The strain was capable to mineralize N,N-bis(carboxymethyl)-L-glutamate in seawater and in synthetic media containing 0–60 g L^?1 sea salts. Growth and adaptation studies indicated that N-carboxymethyl-L-glutamate and L-glutamate are main metabolites.     

Evidences of different salinization sources in the roman coastal aquifer (Central Italy)

The coastal aquifer of Rome is hosted in the Tiber River Delta depositional sequence, in a densely populated area, which was reclaimed at the end of the 19th century. Moderate salinization processes characterize this aquifer. Hydrogeological and hydrochemical surveys were carried out in October 2012 and February 2013 in the southern sector of the Delta. Hydrogeological surveys updated knowledge of groundwater morphology and a detailed conceptual hydrogeological model of the coastal aquifer was realized. Hydrochemical analyses helped to identify the salinization spatial distribution and to specify the main groundwater types. The most salinized water was not detected close to the coastline, where seawater intrusion processes would be expected, but in the inner areas. Moreover, the salinization processes resulted to be slightly marked. Results so far suggest that the source of salinization may be related more to a combination of land use and historical development of the Tiber River Delta, rather than to seawater.     

HCHs and DDTs in Yellow River of Henan section—a typical agricultural area in China: levels,distributions and risks

The levels, potential sources and ecological risks of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in Yellow River of Henan section, a typical agricultural area in China, were investigated. Surface water samples and suspended particulate matters (SPMs) were collected from 23 sites during two seasons. In wet season, the residues of ∑HCHs (α-HCH, β-HCH, γ-HCH and δ-HCH) and ∑DDTs (p,p′-DDT, o,p′-DDT, p,p′-DDE, p,p′-DDD) ranged from 41.7 to 290 and 4.42 to 269 ng/L in surface water, while those varied from 0.86 to 157 and 1.79 to 96.1 ng/g dw in SPM, respectively. Moreover, in surface water, the levels of HCHs and DDTs in wet season were much higher than those in dry season. The reverse was true for residues of HCHs and DDTs in SPM. Compared with the large rivers in other regions, the levels of HCHs and DDTs in the studied area ranked at high levels and the residual concentrations might cause adverse biological risk, especially for ∑HCHs during wet season. Distributions of HCHs and DDTs delineated that the input of tributaries made a significant effect on the residue of HCHs and DDTs in the mainstream. ∑HCHs in surface water were consist of 26.7 % α-HCH, 30.0 % β-HCH, 37.9 % γ-HCH and 5.45 % δ-HCH and those in SPM contained 5.16 % α-HCH, 22.1 % β-HCH, 60.5 % γ-HCH and 12.2 % δ-HCH on average. Combined with ratios of α-HCH/γ-HCH in surface water (0.70) and in SPM (0.09), the results strongly indicated that lindane was recently used or discharged in the studied area. The mean percentage of DDTs′ isomers were 28.7 % p,p′-DDT, 29.8 % o,p′-DDT, 28.1 % p,p′-DDE and 13.4 % p,p′-DDD in surface water, while those were 12.5 % p,p′-DDT, 31.8 % o,p′-DDT, 30.5 % p,p′-DDE and 25.1 % p,p′-DDD in SPM. The ratios of (DDE + DDD)/∑DDTs and o,p′-DDT/p,p′-DDT revealed that the DDTs in the studied area mainly derived from long-term weathering of technical DDTs residue and the input of dicofol.     

A review of combinations of electrokinetic applications

Anthropogenic activities contaminate many lands and underground waters with dangerous materials. Although polluted soils occupy small parts of the land, the risk they pose to plants, animals, humans, and groundwater is too high. Remediation technologies have been used for many years in order to mitigate pollution or remove pollutants from soils. However, there are some deficiencies in the remediation in complex site conditions such as low permeability and complex composition of some clays or heterogeneous subsurface conditions. Electrokinetic is an effective method in which electrodes are embedded in polluted soil, usually vertically but in some cases horizontally, and a low direct current voltage gradient is applied between the electrodes. The electric gradient initiates movement of contaminants by electromigration (charged chemical movement), electro-osmosis (movement of fluid), electrolysis (chemical reactions due to the electric field), and diffusion. However, sites that are contaminated with heavy metals or mixed contaminants (e.g. a combination of organic compounds with heavy metals and/or radionuclides) are difficult to remediate. There is no technology that can achieve the best results, but combining electrokinetic with other remediation methods, such as bioremediation and geosynthetics, promises to be the most effective method so far. This review focuses on the factors that affect electrokinetic remediation and the state-of-the-art methods that can be combined with electrokinetic.