Blackwater rivers and streams have stained or tea‐colored water from tannins released by decaying plant matter. Natural conditions in these waters often differ from non‐blackwater systems. For ...example, the pH and oxygen levels in waters can be very low, but completely natural. We examined an existing USEPA data set and found that blackwaters existed across the contiguous United States but were most common in the east. Water chemistry showed differences between blackwater and non‐blackwater sites, but differences were not consistent across ecoregions making national scale generalizations difficult. Physical habitat data analysis did not show dramatic differences between blackwater and non‐blackwater sites. Blackwater typically arises from streams that drain tannin‐rich bogs/muskeg and wetlands, so as expected blackwater sites had a shorter Euclidean distance to wetlands than non‐blackwater sites and existed in watersheds with a higher percentage of wetland habitat. Blackwaters in Northern and Temperate Plains tended to have higher acid neutralizing capacity, conductivity, and lower True Color; a visual color scale used for water purity. We posit that differences were because Color and Dissolved Organic Carbon at these sites were from buried wetland deposits rather than contemporary wetland habitats. Research needs that may increase our understanding and management of blackwaters include development of an operational definition that includes a classification framework and reference conditions for different blackwater types, identification of stressors and their associated dynamics that negatively impact blackwater systems, and development of data‐driven, consistent, and repeatable assessment methods, including development of targets, protective of unique conditions in blackwater rivers and streams.
Plain Language Summary
Blackwater rivers and stream systems have stained or tea‐colored water due to tannins released by decaying plant matter. Although blackwaters exist across the contiguous United States, they are most common in the eastern United States. Beyond their distinct appearance, the chemistry of blackwater systems can be very different from other stream types. For example, the pH and amount of oxygen in the water can be very low, but completely natural. As a result of these and other characteristics, the fish, plants, and animals that live in blackwaters can also be unique. Because of these considerations, management of these systems can be challenging. To address these challenges, U.S. Environmental Protection Agency scientists are studying these systems. One of their early findings is that different types of blackwaters exist across the country. The team has highlighted the need for a classification system to distinguish among these types. Once this system exists, scientists can begin to identify what is required to protect blackwater systems and the services they supply.
Key Points
There are a substantial number of blackwater rivers in multiple ecoregions of the United States
The water chemistry of blackwater rivers and streams is often very different than that of non‐blackwater rivers and streams
We explore these differences and identify research needs that would contribute to their management and protection
Many areas of industrial production are inseparable from cleaning technology, and traditional cleaning technology is increasingly unable to meet the requirements of modern industry. Laser cleaning ...technology is a new cleaning technology with high efficiency and no chemical pollution. It has the characteristics of non-contact, environmental protection, high efficiency, flexibility, energy saving and wide application range. Compared with mechanical friction cleaning, chemical corrosion cleaning, ultrasonic cleaning, dry ice cleaning and other technologies, it has obvious advantages. At present, laser cleaning technology has been widely used in the fields of aerospace body paint removal, cultural relics sample cleaning, mold and mechanical parts product cleaning, mainly used for paint treatment, rust removal, oil removal and particles. This paper discusses the development trend of laser cleaning technology compared with the traditional laser cleaning technology.
Abstract
In view of the lack of systematic investigation on the evaluation indexes of user-side integrated energy systems, a scientific and systematic evaluation index system is proposed from four ...aspects: energy efficiency, cost-effectiveness, energy supply quality and environmental protection, and the calculation methods of each index are given based on time-series simulation and sequential Monte Carlo simulation. The results indicate that the proposed evaluation index system can provide a foundation for the decision-making of the user-side integrated energy system planning scheme.
Hydrogen production and green chemistry Sidorenko, Alexander; Kutkina, Nina; Nazarova, Nadezhda ...
Journal of physics. Conference series,
12/2022, Letnik:
2373, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Abstract
This paper presents a study on the production of hydrogen and “green chemistry”. The introduction introduces the terminology and historical data, followed by the defining principles that ...describe hydrogen production methods using natural gas, coal, water and biomass as feedstock. Some basics of “green chemistry” are also given. The next section provides an analysis of all hydrogen production methods, the results of the analysis are recorded in a table that allows you to identify the most environmentally friendly solutions. In the conclusion it is stated that the results of the study indicated in the table make it possible to assess the compliance of each of the 13 methods for producing hydrogen with the principles of “green chemistry”, and the assessment and comments do not take into account the economic component of technologies, the main emphasis is on environmental protection.
In 2016, the issue of the Environmental Protection Tax Law indicated the enhancement of environmental protection in China. This study examines the market reaction to firms in heavy-polluting ...industries, and the effects of external legal institutional quality and internal environmental disclosure on firm value around the passage of Environmental Protection Tax Law. Using an event study approach coupled with ordinary least square regressions, the researchers find a significantly negative market reaction to firms in heavy-polluting industries, but this negative reaction varies depending on the expected increase in future regulatory costs. Specifically, the above negative reaction is stronger when the firm reveals that itself or its subsidiary belongs to heavy-polluting industry, however it would be mitigated when a firm is in a region with better quality of legal institutions or discloses environmental improvement activities. Overall, the results are consistent with the market perceiving that the environmental protection tax law enacted would increase regulatory costs for firms in heavy-polluting industries, and also show the higher-quality regional legal institutions and more efforts on environmental protection could relieve the market's pessimism caused by uncertainty.
Review(s) of: Protecting the third pole: Transplanting international law, by Simon Marsden, Published by: Edward Elgar Publishing, Cheltenham, 2019, 328pp, 95 pounds.
Governments have agreed to expand the global protected area network from 13% to 17% of the world's land surface by 2020 (Aichi target 11) and to prevent the further loss of known threatened species ...(Aichi target 12). These targets are interdependent, as protected areas can stem biodiversity loss when strategically located and effectively managed. However, the global protected area estate is currently biased toward locations that are cheap to protect and away from important areas for biodiversity. Here we use data on the distribution of protected areas and threatened terrestrial birds, mammals, and amphibians to assess current and possible future coverage of these species under the convention. We discover that 17% of the 4,118 threatened vertebrates are not found in a single protected area and that fully 85% are not adequately covered (i.e., to a level consistent with their likely persistence). Using systematic conservation planning, we show that expanding protected areas to reach 17% coverage by protecting the cheapest land, even if ecoregionally representative, would increase the number of threatened vertebrates covered by only 6%. However, the nonlinear relationship between the cost of acquiring land and species coverage means that fivefold more threatened vertebrates could be adequately covered for only 1.5 times the cost of the cheapest solution, if cost efficiency and threatened vertebrates are both incorporated into protected area decision making. These results are robust to known errors in the vertebrate range maps. The Convention on Biological Diversity targets may stimulate major expansion of the global protected area estate. If this expansion is to secure a future for imperiled species, new protected areas must be sited more strategically than is presently the case.
This study presents a critical analysis of the environmental challenges regarding global environmental policies and current practices in China. The study provides imperative evidence about the ...current emission control strategies, environmental planning, legislation, policy instruments, and measures to provide a sustainable environment for the present and future generations. The study followed a well-defined analytical methodology to analyse the measures adopted to control emissions as a trade-balancing tool for the environment. The findings indicated that domestic as well as the international collaborations were effective in controlling the present problem of environmental pollution, and suggested a need for collaborative agreements to amend the Environmental Protection Law (EPL). The analytical findings determined that the proposed EPL considered SO2 or NO2 emissions while neglecting an important source of environmental pollution, i.e., CO2 emissions. The research findings also suggested a need for to accelerate efforts in a more professional, practical, and result-oriented manner to analyse the diverse nature of environmental issues. The research highlighted some of the obstacles to the successful implementation of EPL for current and future environmental challenges.
The International Conference on Mechatronics in Energy and Environment Protection-ICMEEP 2020 is held during 16 - 17 October 2020 at Bannari Amman Institute of Technology, Erode through virtual mode. ...This ICMEEP conference is planned to be organized as an annual series in future and this is the first conference in the series which is organized by the Department of Mechatronics of Bannari Amman Institute of Technology. The concept of the conference ICMEEP is to bring together leading academicians, scientists, researchers and industrialists and provide them with a forum to exchange and to share their experiences and research findings in Mechatronics, related to energy savings and environmental protection for the growth of the society. Research on topics related to Mechatronics applications in the energy and environmental problems is of significance because they impact the existence of all living organisms. Many authors from reputed institutions have submitted their papers for this ICMEEP conference. A total of 61 articles have been received and 46 articles are accepted for oral presentation in the virtual conference. All the received papers were undergone peer review by two members of the program committee. Finally program chairs who handle the articles made the final acceptance decisions. List of About the Conference, Topics, Advisory Committee, Keynote Speakers, International Committee, National Committee, Organizing secretary, Convenors, Organizing Committee, Review Committee and Table of Contents are available in this pdf.
Nanofibrous morphology and the doping technique can overcome the problem of electron/hole fast recombination and improve the activity of titanium oxide-based photocatalysts. In this study, ...nanoparticulate and nanofibrous forms of CdTiO.sub.3 -incorporated TiO.sub.2 were synthesized with different cadmium contents; the morphology and composition were determined by SEM, TEM, EDX, and XRD techniques. The nanomorphology, cadmium content, and reaction temperature of Cd-doped TiO.sub.2 nanostructures were found to be strongly affect the hydrogen production rate. Nanofibrous morphology improves the rate of hydrogen evolution by around 10 folds over the rate for nanoparticles due to electron confinement in 0D nanostructures. The average rates of hydrogen production for samples of 0.5 wt.% Cd are 0.7 and 16.5 ml/g.sub.cat. min for nanoparticles and nanofibers, respectively. On the other hand, cadmium doping resulted in increasing the hydrogen production rate from 9.6 to 19.7 ml/g.sub.cat .min for pristine and Cd-doped (2 wt%) TiO.sub.2 nanofibers, respectively. May be the formation of type I heterostructures between the TiO.sub.2 matrix and CdTiO.sub.3 nanoparticles is the main reason for the observed enhancement of photocatalytic activity due to the strong suppressing of electron/holes recombination process. Consequently, the proposed photocatalyst could be exploited to produce hydrogen from scavenger-free solution. Varying reaction temperature suggests that hydrogen evolution over the proposed catalyst is incompatible with the Arrhenius equation. In particular, reaction temperature was found to have a negative influence on photocatalytic activity. This work shows the prospects for using CdTiO.sub.3 as a co-catalyst in photon-induced water splitting and indicates a substantial enhancement in the rate of hydrogen production upon using the proposed photocatalyst in nanofibrous morphology.
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