Critical habitat designation for Canadian listed species: Slow,biased, and incomplete

Although endangered species legislation can be a powerful tool for protecting species, such laws are only as good as their implementation. Under the Canadian Species at Risk Act, Critical Habitat is designated in a Recovery Strategy as the habitat required for the recovery or survival of a listed species. We examined the finalized Recovery Strategies for 234 species and we found poor implementation of Critical Habitat designation for Canadian species. Most listed species (62.9%) lack Critical Habitat; only 11.8% have full Critical Habitat. Many species with Critical habitat obtained it years later than the statutory requirements. Designation is biased taxonomically, by major habitat type, and by lead agency. These results echo findings from the US Endangered Species Act, despite differences between the laws in when designation is supposed to occur. Additional funding and expertise would likely help reduce these delays. We also strongly encourage designation even in the face of incomplete information because of the significant negative consequences that can result from failure to protect the habitat of species at risk of extinction.     

Macroinvertebrate and fish populations in a restored impounded salt marsh 21 years after the reestablishment of tidal flooding

During the last two decades, the State of Connecticut has restored tidal flow to many impounded salt marshes. One of the first of these and the one most extensively studied is Impoundment One in the Barn Island Wildlife Management Area in Stonington, Connecticut. In 1990, twelve years after the re-establishment of tidal flooding, the density of the marsh snail Melampus bidentatus, the numerically dominant macroinvertebrate of the high marsh, in Impoundment One was about half that in reference marshes below the breached impoundment dike. By 1999 the densities of Melampus above and below the dike were not significantly different, but the shell-free biomass was greater above the dike as a result of the somewhat larger number and size of the snails there. Twenty-one years after the renewal of tidal flooding, three marsh macroinvertebrates (the amphipods Orchestia grillus and Uhlorchestia spartinophila and the mussel Geukensia demissa) were significantly less abundant in the previously impounded marsh than in the reference marshes, whereas another amphipod (Gammarus palustris) was more abundant above the breached dike where conditions appeared to be somewhat wetter. In 1991 the fish assemblage in a mosquito-control ditch in Impoundment One was similar to that in a ditch below the breached dike; however, the common mummichog Fundulus heteroclitus appeared to be less abundant in the restoring marsh. By 1999 the number of mummichogs caught in ditches was significantly greater in Impoundment One than in the reference marsh, but the numbers of mummichogs trapped along the tidal creek were comparable above and below the dike. The results obtained in this study and those of other restoring marshes at Barn Island indicate the full recovery of certain animal populations following the reintroduction of tidal flow to impounded marshes may require up to two or more decades. Furthermore, not only do different species recover at different rates on a single marsh, but the time required for the recovery of a particular species may vary widely from marsh to marsh, often independently of other species.     

Impact of Fencing on the Recovery of the Ground Flora on Heavily Eroded Slopes of a Deciduous Forest

This paper seeks to outline early stages in the recovery of forest ground flora on eroded slopes impacted by recreation activities and to suggest how these data might be applied in the formulation of management policies for forest recreation areas. Based on a fencing experiment in the Sonian Forest near Brussels, we investigated whether, over a 6-year period, the vegetation was able to recover after having been destroyed by recreation use. Short-term trends in overall species composition were already observable during this 6-year study. Species recovery on eroded hills was related to slope, aspect, and soil type. During the considered time scale, the proportion of hemicryptophytes and the number of ancient forest species increased significantly. A downward trend was detected for Ellenbergs nitrogen and temperature indexes and for the proportion of therophytes and pioneer plants of disturbed places. Changes in species frequencies suggest six recovery strategies: early, late, expanding, disappearing, transient, and fluctuating species. Aside from seedling reproduction from overstory influences, Luzula sylvatica appeared to be the most resilient of the species identified in the study since this species has the highest global frequency in our sampling plots and has increased its cover during the study period. Study results indicate that (1) protection from recreation has initiated the recovery of species in the herb layer, but (2) it may take a long time before vegetation previously present in the ground flora may recover in both density and species composition.     

Waste minimization study in a solvent-based paint manufacturing plant

Solvent-based paint manufacturing plants produce significant quantities of hazardous waste, which must be properly treated before it can be disposed. Since the cost for treating this waste is high, reducing the quantity of waste has become a crucial issue in this industry.Waste minimization options are beneficial for the owner of the plant as well as for the environment. The quantity of hazardous waste can be minimized by changing the plant's technology or by substituting hazardous substances, which are used in the paint manufacturing process, with environmentally friendly ones. Furthermore, separating the various waste streams makes it easier to recover raw materials and enhances the possibility of their reuse within the production process. This will decrease operational costs for the plant.This paper presents a case study of waste minimization in a solvent-based paint manufacturing plant. Source reduction, recovery, and recycling methods are taken into consideration. Its aim is to develop an understanding of the facility's waste generating processes, to suggest ways to reduce the waste production, and finally to select an appropriate waste minimization option to suggest to the plant. Some of the suggested methods are currently being practiced while others are at initial stage of development.     

油气挥发污染控制技术探讨

油品储运过程中油气的挥发带来了严重的环境污染。利用油气回收技术作为主要的降耗措施已得到重视和推广应用。通过对储运过程中污染现状的分析及各类油气回收控制技术特点的分析,为今后的技术开发指出方向。     

Disassemblability of end-of-life vehicle: a critical review of evaluation methods

Environmental sustainability has become the main items of contest in the automotive industries. Therefore in the order to reduce the environmental impact of end-of-life vehicles, European Union, Japan, USA, and Australia laws require manufacturers to take back their products at the end of their useful life and recycle them. In order to enhance the recycling rate of the vehicle, disassemblability of the automotive components has been a major concern. In the chain of end-of-life, except for landfill and incineration, components of economic value destined for reuse, remanufacture, or recycling have first to be disassembled from the end-of-life vehicles. There are several efforts within the academic community to rationalise design for disassembly and recycling, and several attempts by industry to study these issues in the context of specific products. Recent publications offer a broad perspective on recyclability and disassemblability. It is therefore necessary to determine the optimal stage of disassembly, when all economically valuable components are retrieved. This paper presents a review of several disassemblability methods, including spread sheet-like chart, end-of-life value and time for disassembly. The review concludes on the need for an effective disassembly method in order to enhance the recovery of products.     

Recent advances in activity inhibition,recovery and enhancement,and application of the anaerobic ammonium oxidation process北大核心CSCD

Anaerobic ammonium oxidation (Anammox) is a biological process that has the advantages of saving energy and being highly efficient. However, there are some problems with it such as slow proliferation and activity inhibition of Anammox bacteria in practical applications. First, we introduce the inhibitory effects of Anammox by substrate and non-substrate materials, including nitrite, organic and inorganic substances, and others, and elaborated on activity recovery approaches such as controlling the operation parameters and adding sludge. The effects of the addition of inorganic carbon, Anammox intermediates, Fe, and conductive materials on Anammox are then reviewed in detail, and three Anammox metabolic pathways are summarized. Finally, we discuss the problems (including NOB inhibition and low temperature) and countermeasures when Anammox is applied for wastewater treatment as a mainstream technology, and we summarized the measures of NOB washout by free ammonia and free nitrite solutions and methods to cope with low temperatures, including selecting suitable reactor types and culture methods. Meanwhile, we analyzed the interactions among the intermediates and the synergy between Anammox and denitrification and suggest the potential of applying Anammox for flue gas denitrification and anaerobic aromatic hydrocarbon biodegradation. Further studies are suggested regarding multifactor composite inhibition, Anammox physiological characteristics, and intermediate metabolic mechanisms as well as regarding methods for avoiding adverse factors in mainstream wastewater treatment. © 2018 Science Press. All rights reserved.     

综合利用石墨化废旧辅料的新方法

炭素石墨制品生产过程中产生的石墨化废旧辅料,在炭素行业是最有开发潜力的固体废物。通过初加工可实现回收利用,经研制开发新产品可实现综合利用。该综合利用方法表明,在实现综合利用中可获得大的经济效益和可观的社会效益。      

Recovery of metal values from zinc solder dross

Zinc solder dross containing 14.8% Sn, 16.3% Pb, 0.41% Al and 64.5% Zn was leached with 3% H₂SO₄ at 45°C for 1 h. Zinc and aluminum went into solution, whereas lead and tin remained with the residue. Aluminum was selectively precipitated as calcium aluminum carbonate by treating the sulphate leachate with limestone at pH 4.8. Zinc sulphate solution was either evaporated to obtain zinc sulphate crystals or precipitated as basic zinc carbonate at pH 6.8. The undissolved lead and tin were leached with 5 M hot hydrochloric acid. The major part of lead chloride ( 73%) was separated by cooling the leached products down to room temperature. From the soluble fraction, tin was recovered as hydrated tin oxide by alkylation with caustic soda at pH 2.4, while the remaining lead was separated at pH 8.5 as lead hydroxide. A process flowsheet had been suggested which involved two-stage hydrometallurgical treatment. Parameters affecting the recovery efficiency of the suggested method such as temperature, time, pH and acid: solid stoichiometric ratio were investigated. Results obtained revealed that the optimum leaching conditions were achieved by using 20 ml of 3% H₂SO₄ acid/g dross for 1 h at 45°C. Recovery efficiency of the metal salts was 99.1, 99.4, 99.6 and 99.5% for Zn, Al, Pb and Sn respectively. Recovery efficiency was related to the solubility of the concerned salts under the given experimental conditions.