Impact and effectiveness of Bio-Coke conversion from biomass waste as alternative source of coal coke in Southeast Asia

Journal of Material Cycles and Waste Management - Growing concern over fossil fuel depletion and the environmental impact of greenhouse gases have driven the demand for solid biofuel energy as an...     

Marine macrophytes as effective lead biosorbents

Several species of seagrass and marine macrophytes were investigated for their biosorption performance in the removal of lead from aqueous solution. The effect of pH on the equilibrium of the seagrass Cymodocea nodosa as a biosorbent also was studied. It was found that increasing pH increased lead biosorption, with a maximum uptake of approximately 140 mg/g in the range pH 3.3 to 5. Equilibrium data at different pH levels were successfully fitted to competitive equilibrium models. In addition, the seaweeds belonging to different phyla (i.e., Chlorophyta, Heterokontophyta, and Rhodophyta) were studied for the effect of their structure on equilibrium at a constant pH 5. The brown algae (Heterokontophyta) showed the highest potential for lead sorption, with a maximum uptake of 220 mg/g for C. compressa and 140 mg/g for S. lomentaria. The green algae (Chlorophyta) showed lead uptake in the range 40 to 90 mg/g, and the red algae (Rhodophyta) was least effective, with uptake in the range 10 to 40 mg/g.     

Investigation of insecticide leaching from potted nursery stock and aquatic health benefits of bioretention cells receiving nursery runoff

Tree nurseries and greenhouses within the USDA red imported fire ant (RIFA) quarantine zone are required to incorporate insecticides into their potting media to prevent artificial spread of RIFA. Bifenthrin and fipronil are two common insecticides that are incorporated into potting media. During irrigation and stormwater events, there is potential for insecticides to leach from nursery pots, resulting in the contamination of nearby surface waters. In this study, occurrences of insecticides in simulated nursery runoff were compared with two irrigation strategies and two types of containers in single pot leaching and field runoff simulations. In addition, toxicity of pot leachate to the aquatic invertebrate, Hyallela azteca, was measured, and removal efficiencies of insecticides from bioretention cell media were evaluated. Overhead irrigation resulted in significantly higher concentrations than drip irrigation, and RootMaker® pots allowed more leaching as compared to standard slick-wall pots. However, in all tests, the average concentration of bifenthrin during 15 days of leaching in both pot and field simulations was greater than 200 ng/L; more than 100-fold greater than the LC₅₀ for H. azteca. Toxicity studies confirmed this level of toxicity. Higher amounts of compost, 20 and 40 %, in bioretention cell media resulted in greater percent reduction of both bifenthrin and fipronil. This study determined that management techniques may be able to limit the amount of insecticide that leaches from pots and runs off to receiving water bodies. Specifically, the selection of appropriate pot types, irrigation strategies, or filtering runoff through bioretention cells may reduce contamination loads. Thus, further best management strategies such as the use of bioretention cells are needed in nursery and greenhouse facilities to prevent surface water runoff from transporting toxic insecticides.     

Modification of Sulfur Dioxide Injury to Tobacco and Tomato by Varying Nitrogen and Sulfur Nutrition

The body of information presented in this paper is directed to plant scientists who are concerned with factors which modify the susceptibility of plants to air pollutants.

Tobacco and tomato plants grown in sand-solution culture with varying levels of nitrogen or sulfur were exposed to injurious levels of sulfur dioxide. Plants of both species which were deficient in either nutrient exhibited decreased susceptibility to the gas compared with plants grown at optimal levels of each nutrient. Foliage of these plants was also found to have increased stomatal resistance as measured by a porometer and decreased total sulfur accumulations. Plants grown at optimum levels of each nutrient showed increased susceptibility over that of the deficient plants. Stomatal resistance was lower and sulfur accumulation was greater than in the deficient plants. At the supra-optimal nitrogen and sulfur levels, there were differences in susceptibility. Over-abundant nitrogen appeared to decrease susceptibility whereas over-supplies of sulfur increased it.

The response of plants with deficient or optimal supplies of either nutrient might be explained by the effects of nutrition on stomatal activity and hence on ability to absorb SO₂S from the atmosphere, mineral deficiency being known to increase stomatal resistance, and mineral sufficiency, to decrease stomatal resistance by virtue of increased efficiency of water use. The difference in response between plants overfertilized with respect to nitrogen or sulfur is explained by the fact that sulfur is both nutrient and phytotoxicant at the same time. Having already been oyersupplied with sulfur by absorption from the nutrient substrate, the high-sulfur plants were unable to withstand additional sulfur accumulation from the atmosphere and hence were more severely injured.

Increased carbohydrate accumulation in the nitrogen- and sulfur-deficient plants might play an additional role in protection from SO2-injury.     

Cost–benefit analysis of beach-cast harvest: Closing land-marine nutrient loops in the Baltic Sea region

Harvesting beach-cast can help mitigate marine eutrophication by closing land-marine nutrient loops and provide a blue biomass raw material for the bioeconomy. Cost–benefit analysis was applied to harvest activities during 2009–2018 on the island of Gotland in the Baltic Sea, highlighting benefits such as nutrient removal from the marine system and improved recreational opportunities as well as costs of using inputs necessary for harvest. The results indicate that the activities entailed a net gain to society, lending substance to continued funding for harvests on Gotland and assessments of upscaling of harvest activities to other areas in Sweden and elsewhere. The lessons learnt from the considerable harvest experience on Gotland should be utilized for developing concrete guidelines for carrying out sustainable harvest practice, paying due attention to local conditions but also to what can be generalized to a wider national and international context.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01641-8.     

Yttrium recovery from primary and secondary sources: A review of main hydrometallurgical processes

Yttrium is important rare earths (REs) used in numerous fields, mainly in the phosphor powders for low-energy lighting. The uses of these elements, especially for high-tech products are increased in recent years and combined with the scarcity of the resources and the environmental impact of the technologies to extract them from ores make the recycling waste, that contain Y and other RE, a priority.The present review summarized the main hydrometallurgical technologies to extract Y from ores, contaminated solutions, WEEE and generic wastes. Before to discuss the works about the treatment of wastes, the processes to retrieval Y from ores are discussed, since the processes are similar and derived from those already developed for the extraction from primary sources.Particular attention was given to the recovery of Y from WEEE because the recycle of them is important not only for economical point of view, considering its value, but also for environmental impact that this could be generated if not properly disposal.     

Recovery of yttrium from fluorescent powder of cathode ray tube,CRT: Zn removal by sulphide precipitation

This work is focused on the recovery of yttrium and zinc from fluorescent powder of cathode ray tube (CRT). Metals are extracted by sulphuric acid in the presence of hydrogen peroxide. Leaching tests are carried out according to a 2² full factorial plan and the highest extraction yields for yttrium and zinc equal to 100% are observed under the following conditions: 3 M of sulphuric acid, 10% v/v of H₂O₂ concentrated solution at 30% v/v, 10% w/w pulp density, 70 °C and 3 h of reaction.Two series of precipitation tests for zinc are carried out: a 2² full factorial design and a completely randomized factorial design. In these series the factors investigated are pH of solution during the precipitation and the amount of sodium sulphide added to precipitate zinc sulphide. The data of these tests are used to describe two empirical mathematical models for zinc and yttrium precipitation yields by regression analysis. The highest precipitation yields for zinc are obtained under the following conditions: pH equal to 2–2.5% and 10–12% v/v of Na₂S concentrated solution at 10% w/v. In these conditions the coprecipitation of yttrium is of 15–20%.Finally further yttrium precipitation experiments by oxalic acid on the residual solutions, after removing of zinc, show that yttrium could be recovered and calcined to obtain the final product as yttrium oxide. The achieved results allow to propose a CRT recycling process based on leaching of fluorescent powder from cathode ray tube and recovery of yttrium oxide after removing of zinc by precipitation. The final recovery of yttrium is 75–80%.     

The Impacts of Water Conservation Strategies on Water Use: Four Case Studies1

Tsai, Yushiou, Sara Cohen, and Richard M. Vogel, 2011. The Impacts of Water Conservation Strategies on Water Use: Four Case Studies. Journal of the American Water Resources Association (JAWRA) 47(4):687‐701. DOI: 10.1111/j.1752‐1688.2011.00534.x Abstract: We assessed impacts on water use achieved by implementation of controlled experiments relating to four water conservation strategies in four towns within the Ipswich watershed in Massachusetts. The strategies included (1) installation of weather‐sensitive irrigation controller switches (WSICS) in residences and municipal athletic fields; (2) installation of rainwater harvesting systems in residences; (3) two outreach programs: (a) free home indoor water use audits and water fixture retrofit kits and (b) rebates for low‐water‐demand toilets and washing machines; and (4) soil amendments to improve soil moisture retention at a municipal athletic field. The goals of this study are to summarize the effectiveness of the four water conservation strategies and to introduce nonparametric statistical methods for evaluating the effectiveness of these conservation strategies in reducing water use. It was found that (1) the municipal WSICS significantly reduced water use; (2) residences with high irrigation demand were more likely than low water users to experience a substantial demand decrease when equipped with the WSICS; (3) rainwater harvesting provided substantial rainwater use, but these volumes were small relative to total domestic water use and relative to the natural fluctuations in domestic water use; (4) both the audits/retrofit and rebate programs resulted in significant water savings; and (5) a modeling approach showed potential water savings from soil amendments in ball fields.     

Inclusion of sex chromosomes in noninvasive prenatal testing in Asia,Australia, Europe and the USA: A survey study

Objective

To examine the extent to which sex chromosomes are included in current noninvasive prenatal testing (NIPT) and the reporting practices with respect to fetal chromosomal sex and sex chromosome aberrations (SCAs), in addition to an update on the general implementation of NIPT.

Method

A questionnaire addressing the research objectives was distributed by email to fetal medicine and clinical genetics experts in Asia, Australia, Europe and the USA.

Results

Guidelines on NIPT are available in the majority of the included countries. Not all existing guidelines address reporting of fetal chromosomal sex and SCAs. In most settings, NIPT frequently includes sex chromosomes (five Australian states, China, Hong Kong, Israel, Singapore, Thailand, USA and 23 of 31 European countries). This occurs most often by default or when parents wish to know fetal sex. In most settings, a potential SCA is reported by stating the risk hereof as “low” or “high” and/or by naming the SCA. Less than 50% of all pregnant women receive NIPT according to respondents from three Australian states, China, Israel, Singapore, Thailand and 24 of 31 European countries. However, this percentage, the genomic coverage of NIPT and its application as primary or secondary screening vary by setting.

Conclusion

In most of the studied countries/states, NIPT commonly includes sex chromosomes. The reporting practices concerning fetal chromosomal sex and SCAs are diverse and most commonly not addressed by guidelines. In general, NIPT is variably implemented across countries/states.     

Joining forces toward proactive elephant and rhinoceros conservation

Proactive approaches that anticipate the long-term effects of current and future conservation threats could increase the effectiveness and efficiency of biodiversity conservation. However, such approaches can be obstructed by a lack of knowledge of habitat requirements for wildlife. To aggregate and assess the suitability of current information available on habitat requirements needed for proactive conservation, we conducted a systematic review of the literature on elephant and rhinoceros habitat requirements and synthesized data by combining a vote counting assessment with bibliometric and term maps. We contextualized these numeric and terminological results with a narrative review. We mapped current methods, results, terminology, and collaborations of 693 studies. Quantitative evidence for factors that influence the suitability of an area for elephants and rhinoceros was biased toward African savanna elephants and ecological variables. Less than one third of holistic approaches considered equal amounts of ecological and anthropogenic variables in their assessments. There was a general lack of quantitative evidence for direct proxies of anthropogenic variables that were expected to play an important role based on qualitative evidence and policy documents. However, there was evidence for a segregation in conceptual frameworks among countries and species and between science versus policy literature. There was also evidence of unused potential for collaborations among southern hemisphere researchers. Our results indicated that the success of proactive conservation interventions can be increased if ecological and anthropogenic dimensions are integrated into holistic habitat assessments and holistic carrying capacities and quantitative evidence for anthropogenic variables is improved. To avoid wasting limited resources, it is necessary to form inclusive collaborations within and across networks of researchers studying different species across regional and continental borders and in the science–policy realm.