Growth of Avicennia marina and Ceriops decandra seedlings inoculated with halophilic azotobacters

Inoculation of azotobacter has significant positive effects on the growth characteristics and pigments in mangrove seedlings of Avicennia marina and Ceriops decandra. The bacterial inoculation significantly increased the root dry biomass at the maximum of 75.8% at 30 gl(-1) salinity in Ceriops decandra. But in Avicennia marina, the shoot dry biomass was increased significantly at the maximum of 56.12% at 30 gl(-1) salinity in general, the Azotobacter beijerinkii improved the growth characteristics better in both species of mangroves preferably at higher salinity levels in A. marina and at a range of salinity in C. decandra. The results recommend this forraising vigorous seedlings under nursery conditions.     

The ISO 26000’s labor environmental issues during COVID-19: does corporate social responsibility help? Evidence from the Egyptian small and medium enterprises

Environmental Science and Pollution Research - Based on both the “stakeholder” and “cognitive” theories, this study shed light on the optimistic side of the COVID-19...     

Studies on the influence of mycorrhiza on the growth and physiology of Vigna unguiculata and Abelmoschus esculentus

Diverse forms of microorganisms present in the soil and near the roots of plants, which play a vital role in numerous physiological processes, have attracted the attention of scientists. The dynamic microbial associations may be saprophytic, pathogenic, or symbiotic. The most widespread symbiosis of plants is the mycorrhizal association between root-inhabiting fungi and the feeder roots of plants. The present study was conducted to study the effects of arbuscular mycorrhizal fungi on mineral nutrition of Vigna unguiculata and Abelmoschus esculentus. The experiment comprised of uninoculated seedlings and seedlings inoculated with Glomus mosseae. The chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, protein, nitrate, nitrogen, and phosphorus content showed an increase in vesicular arbuscular mycorrhiza fungus-treated seedlings compared to non-mycorrhizal plants. The total soluble sugars and soluble starch content in leaves of all selected plant species in the present study showed a decrease in mycorrhizal seedlings compared to non-mycorrhizal seedlings.     

Performance evaluation of NOAA-EPA developmental aerosol forecasts

To aid air quality model development and assess air quality forecasts, the Meteorological Development Laboratory (MDL) provided categorical verification metrics for developmental aerosol predictions. The National Air Quality Forecasting Capability (NAQFC) generated 48 h (of) gridded hourly developmental predictions for the lower 48 states (CONUS) domain in 12 km horizontal spacing. The NAQFC uses the North American Mesoscale (NAM) model with EPA’s Community Multiscale Air Quality (CMAQ) model to produce predictions of ground level aerosol concentrations. We used bilinear interpolation to calculate predicted daily maximum values at the location of the observation sites. We compared these interpolated predicted values to the observed daily maximum to produce 2 × 2 contingency tables, with a threshold of 40 μg/m³ during the months of March–August, 2007. The model showed some degree of skill in predicting aerosol exceedances. These results are preliminary as the NAQFC model for aerosol prediction is in the developmental stage. A more comprehensive performance evaluation will be accomplished in 2008, when more data become available. Our verification metrics included categorical analyses for Fraction Correct (FC) or percent correct (FC × 100), Threat Score (TS) or Critical Success Index (CSI), Probability of Detection (POD), and the False Alarm Rate (FAR), Mean Absolute Error (MAE) and mean algebraic error or bias, where bias is forecast minus observation. Graphic products included weekly statistics for the CONUS displayed in the form of bar charts, scatterplots, and graphs. In addition, we split the CONUS into six geographic regions and provided regional statistics on a monthly basis. MDL produced spatial maps of daily 1-h maximum predicted aerosol values overlaid with the corresponding point observations. MDL also provided spatial maps of the daily maximum of the 24-h running average. We derived the 24-h running average from the 1-h average predicted aerosol values and observations.     

Co-composting solid biowastes with alkaline materials to enhance carbon stabilization and revegetation potential

Co-composting biowastes such as manures and biosolids can be used to stabilize carbon (C) without impacting the quality of these biowastes. This study investigated the effect of co-composting biowastes with alkaline materials on C stabilization and monitored the fertilization and revegetation values of these co-composts. The stabilization of C in biowastes (poultry manure and biosolids) was examined by their composting in the presence of various alkaline amendments (lime, fluidized bed boiler ash, flue gas desulphurization gypsum, and red mud) for 6 months in a controlled environment. The effects of co-composting on the biowastes’ properties were assessed for different physical C fractions, microbial biomass C, priming effect, potentially mineralizable nitrogen, bioavailable phosphorus, and revegetation of an urban landfill soil. Co-composting biowastes with alkaline materials increased C stabilization, attributed to interaction with alkaline materials, thereby protecting it from microbial decomposition. The co-composted biowastes also increased the fertility of the landfill soil, thereby enhancing its revegetation potential. Stabilization of biowastes using alkaline materials through co-composting maintains their fertilization value in terms of improving plant growth. The co-composted biowastes also contribute to long-term soil C sequestration and reduction of bioavailability of heavy metals.     

Effects of untreated hospital effluents on the accumulation of toxic metals in sediments of receiving system under tropical conditions: Case of South India and Democratic Republic of Congo

Physicochemical and ecotoxicological analyses have been performed to assess the quality of sediments receiving untreated hospital effluents from Indian and Democratic Republic of Congo (DRC) hospitals. The sediments were collected monthly and characterized for grain size, organic matter, total organic carbon, total carbon, nitrogen, phosphorus, toxic metals and ecotoxicity. The results highlight the high concentration of toxic metals from the Indian hospital effluent receiving systems, especially for Cr, Cu, As, Zn and Hg. On the other hand, the metal concentrations in the sediment receiving system from DRC are low (e.g. maximum Hg and Zn concentration were 0.46 and 48.84 mg kg⁻¹ respectively). Ostracods exposed to sediment samples H2 (September month sample) and H3 (June and September month samples) were found dead after 6 d of exposure whereas the higher mortality rate for Congo sediments was 23% but was accompanied with 33 ± 7% of growth inhibition. The results of this study show the variation of sediment composition on toxic metal levels as well as toxicity related to both, the type of hospitals and the sampling period. Additionally, hospital effluent disposal practices at the study sites can lead to the pollution of water resources and may generate risks for aquatic organisms and human health.     

Effect of industrial waste products on phosphorus mobilisation and biomass production in abattoir wastewater irrigated soil

This study evaluated the effect of alkaline industrial by-products such as flyash (FA) and redmud (RM) on phosphorus (P) mobilisation in abattoir wastewater irrigated soils, using incubation, leaching and plant growth (Napier grass [Pennisetum purpureum]) experiments. The soil outside the wastewater irrigated area was also collected and treated with inorganic (KH₂PO₄ [PP]) and organic (poultry manure [PM]) P treatments, to study the effect of FA and RM on P mobilisation using plant growth experiment. Among the amendments, FA showed the highest increase in Olsen P, oxalic acid content and phosphatase activity. The highest increase in Olsen P for PM treated non-irrigated soils showed the ability of FA and RM in mobilising organic P better than inorganic P (PP). There was over 85 % increase in oxalic acid content in the plant growth soils compared to the incubated soil, showing the effect of Napier grass in the exudation of oxalic acid. Both amendments (FA and RM) showed an increase in phosphatase activity at over 90 % at the end of the 5-week incubation period. The leaching experiment indicated a decrease in water soluble P thereby ensuring the role of FA and RM in minimising P loss to water bodies. FA and RM showed an increase in plant biomass for all treatments, where FA amended soil showed the highest increase as evident from FA’s effect on Olsen P. Therefore, the use of FA and RM mobilised P in abattoir wastewater irrigated soils and increased biomass production of Napier grass plants through root exudation of oxalic acid.     

Solid waste management of small island developing states—the case of the Seychelles: a systemic and collaborative study of Swiss and Seychellois students to support policy

Solid waste management (SWM) is a significant challenge for the Seychelles. Waste generation, fueled by economic development and tourism, increases steadily, while landfilling continues to be the main disposal path, thus exacerbating the island nation’s specific weaknesses. Due to the small scale of the Seychelles economy, there is little capital available to stimulate innovations in SWM and generate the knowledge for setting priorities and guiding SWM action. Students from ETH Zurich and UniSey conducted a transdisciplinary case study (tdCS) to fill this knowledge gap and gain insights into the obstacles and opportunities related to sustainable SWM. The tdCS approach allowed students to gain comprehensive and in-depth knowledge about the SWM system required to set priorities for action and next steps. The government should streamline the different financial frameworks according to a clear principle (e.g., polluter pays principle). Specific biogenic waste streams represent a potential source of energy and fertilizers. Expanding the scope and densifying the network of collection points could help raise recycling rates of other waste fractions. Diverting biogenic waste and recycling more glass, metals, paper, and plastics would also significantly reduce landfilling rates. Regardless of future amounts of waste ending up on landfills, the latter must be reengineered before the surrounding environment suffers major adverse impacts. All these actions imply a government-driven approach which integrates the views of stakeholders and consumers alike.     

Evaluation of groundwater quality in and around Peenya industrial area of Bangalore, South India using GIS techniques

Groundwater resource forms a significant component of the urban water supply. Declining groundwater levels in Bangalore Urban District is generally due to continuous overexploitation during the last two decades or more. There is a tremendous increase in demand in the city for good quality groundwater resource. The present study monitors the groundwater quality using geographic information system (GIS) techniques for a part of Bangalore metropolis. Thematic maps for the study area are prepared by visual interpretation of SOI toposheets on 1:50,000 scale using MapInfo software. Physicochemical analysis data of the groundwater samples collected at predetermined locations form the attribute database for the study, based on which spatial distribution maps of major water quality parameters are prepared using MapInfo GIS software. Water quality index was then calculated by considering the following water quality parameters--pH, total dissolved solids, total hardness, calcium hardness, magnesium hardness, alkalinity, chloride, nitrate and sulphate to find the suitability of water for drinking purpose. The water quality index for these samples ranged from 49 to 502. The high value of water quality index reveals that most of the study area is highly contaminated due to excessive concentration of one or more water quality parameters and that the groundwater needs pretreatment before consumption.