Stratospheric Ozone Research Articles

Ecosocialism and Its Implication to the Nigerian State

The environmental crisis remains unabated. It is still raging on in phenomena such as gas flaring, deforestation, depletion of the ozone layer, climate change, desertification, unplanned urbanization, and so forth. The impact of the crisis is felt in every region of the world including Nigeria. Nigeria has experienced many environmental problems like the ones mentioned above. Others are soil erosion, illegal mining, environmental insecurities, violent struggles over natural resources, etc. Various ideologies have been proposed for curbing the environmental crisis such as communalism, socialism, capitalism, nationalism, democracy, communism, ecofeminism, ecowomanism, and so forth. This paper critically and hermeneutically examines the ideology of ecosocialism and its appropriateness to the Nigerian state. The paper shows why ecosocialism has some positive ideas that should inspire the Nigerian state in ecological protection, it should not be adopted in an uncritical manner hook, line, and sinker. The paper reveals that Nigeria is troubled by many environmental problems. It concludes that the good points of ecosocialism should be adopted and used to create an environmentally friendly Nigerian state.

Repeated pulses of volcanism drove the end-Permian terrestrial crisis in northwest China

The Permo-Triassic mass extinction was linked to catastrophic environmental changes and large igneous province (LIP) volcanism. In addition to the widespread marine losses, the Permo–Triassic event was the most severe terrestrial ecological crisis in Earth’s history and the only known mass extinction among insects, but the cause of extinction on land remains unclear. In this study, high-resolution Hg concentration records and multiple-archive S-isotope analyses of sediments from the Junggar Basin (China) provide evidence of repeated pulses of volcanic-S (acid rain) and increased Hg loading culminating in a crisis of terrestrial biota in the Junggar Basin coeval with the interval of LIP emplacement. Minor S-isotope analyses are, however, inconsistent with total ozone layer collapse. Our data suggest that LIP volcanism repeatedly stressed end-Permian terrestrial environments in the ~300 kyr preceding the marine extinction locally via S-driven acidification and deposition of Hg, and globally via pulsed addition of CO2.

Multi-Omics Analysis Reveals the Molecular Mechanisms of the Glycolysis and TCA Cycle Pathways in Rhododendron chrysanthum Pall. under UV-B Stress

UV-B radiation is becoming a bigger threat to plants as a result of the ozone layer’s depletion. As an alpine plant, Rhododendron chrysanthum Pall. (R. chrysanthum) may grow regularly under UV-B radiation throughout its lengthy acclimatization period, although the mechanism of acclimatization is still poorly understood. The current investigation uncovered a number of adaptation strategies that R. chrysanthum has developed in reaction to UV-B rays. UV-B radiation impeded photosynthesis and damaged the photosystem, according to OJIP testing. Through transcriptomics and proteomics analyses, this study found that the differential proteins and differential genes of R. chrysanthum were significantly enriched in glycolysis and tricarboxylic acid (TCA) cycle pathways after UV-B treatment. The metabolomics results showed that a total of eight differential metabolites were detected in the glycolytic and TCA cycle pathways, and the changes in the expression of these metabolites reflected the final outcome of gene regulation in the glycolytic and TCA cycle pathways. The combined experimental results demonstrated that R. chrysanthum’s photosynthetic system was impacted by UV-B stress and, concurrently, the plant activated an adaptation mechanism in response to the stress. To maintain its energy supply for growth, R. chrysanthum adapts to UV-B stress by adjusting the expression of the relevant proteins, genes, and metabolites in the glycolytic and TCA cycling pathways. This study provides a new perspective for understanding the changes in the carbon metabolism of R. chrysanthum under UV-B stress and its mechanisms for UV-B resistance, and provides an important theoretical basis for the study of enhancing plant resistance to stress.

Enhancing the Mechanical Properties of Green Concrete Blocks Mixture

Abstract Concrete is a very abundant building material and flexible in construction. Yet cement is the main material used in concrete mixture, which consumed a lot of energy and money. Cement is a very un-eco-friendly material when it comes to production and is a main contributor to global warming. On the other hand, Polymers can be toxic to people, fauna, and flora. In the last century, Egyptian citizens complained that the waste has increased, and the inappropriate waste disposal effect the Egyptian health and quality of life. The alternative is to burn the polymers; however, it will produce toxic emissions that will break down the ozone layer. Previous researchers tried to replace cement with an alternative in the concrete mixture. Therefore, this research intends to create a green concrete block with cement-less mixture and use polymers as a binding material in the blocks. This research will follow the experimental method after discussing the properties of the materials. Then a concrete mix will be created, and a percentage of cement will be replaced; thus, making a cheap concrete mixture that has less cement and is more ecological and economical. Tests will be performed to determine if the proposed concrete mixture is suitable for mass production and doesn’t violate the international standards. The performed tests will include compressive strength, tensile strength, and abrasion. finally, a cost analysis will be calculated to compare the construction costs before and after using the proposed concrete mixture.

Effects of Carbon Dioxide and Nitrogen Oxides on Climate Change in Afghanistan

Climate change is a global threat to the environment and human health. Two of the main greenhouse gases that cause the greenhouse effect and raise global temperatures are carbon dioxide and nitrogen oxides. In this review paper, we investigated the effects of carbon dioxide and nitrogen oxides on climate change and the effects of climate change on Afghanistan. We found that high concentrations of carbon dioxide, which is now CO2 levels, have increased by 50% than before the Industrial Revolution, contributing to a rise in global temperature and precipitation. At the same time, Nitrous oxide is an important greenhouse gas, with 310-fold higher potential for global warming than CO2 and leads to the depletion of stratospheric Ozone and other Nitrogen oxides, has a significant impact on plant health, including effects on chlorophyll levels, oxidative stress, and antioxidant responses. Afghanistan’s climate change is predicted to increase the country’s prevalence of illnesses linked to dust storms and poor air quality, especially in Kabul, the nation’s capital. In addition, air pollution in Kabul is also likely to increase as a result of climate change. The alarming impacts of air pollution, with more than 3,000 deaths attributed to air pollution annually. Additionally, at least 700,000 individuals in Kabul have experienced various respiratory diseases. Due to climate change, Afghanistan’s total glacier area has shrunk by 13.8%. In 2023, Afghanistan experienced early snow melt and below-average precipitation, causing second-season and irrigated crops to have less access to water. Reducing emissions and coping with the changing climate are essential steps towards tackling the complex issues these gases present and their wider effects on the environment and human health.

Life Cycle Assessment Analysis Based on Material Selection in Sustainable Airport Buildings

Sustainable airport buildings aim to minimize environmental impacts through energy efficiency, water conservation, and waste management. This is achieved by employing green building materials and utilizing renewable energy sources to reduce their carbon footprint. In this study, life cycle assessment (LCA) was conducted to assess the environmental impacts of three main construction materials—concrete, steel, and wood—used in sustainable airport buildings. These materials were selected for their widespread use in eight different airport terminal buildings with sustainability certifications. The environmental impacts of these materials were calculated and compared using OpenLCA 1.9.0 software and the ECOinvent database, adhering to the standards set forth by the Environmental Product Declaration (EPD) initiative. The findings indicate that wood, as a construction material, has a significantly lower impact on global warming compared to steel and concrete, with a global warming potential (GWP) ratio of less than 60%. Steel, with a GWP of approximately 90% of that of concrete, also showed a lower impact than concrete. Additionally, other environmental impacts, such as stratospheric ozone depletion potential (ODP) and acidification potential (AP), were also examined, highlighting the trade-offs associated with each material.

Life Cycle Assessment of Natural Gas Production in Java Sea-East Java Province, Indonesia

Energy products including natural gas play a very important role in the context of global economic, industrial, and infrastructure development. However, it is undeniable that the production process from raw material extraction to ready-to-use products has an impact on the environment. This study was conducted to evaluate the environmental impact of natural gas production in the Kepodang field, East Java Province, Indonesia. The next objective is to analyze the magnitude and significance of the impact or hotspot analysis. The characterization results for 4 main categories show: Global Warming Potential 70.02 kg CO₂ eq, Ozone Layer Depletion 1.11E-06 kg CFC-11 eq, Acidification Potential 0.65 mol H+ eq, Marine Eutrophication 0.30 kg N eq, and Freshwater Eutrophication 2.17E-03kg P eq. The results also show that throughout the life cycle of this product, the largest contributor to environmental impacts is in the downstream phase, especially the user gas metering unit process. This is due to the 200 km of pipelines for product transportation from the Central Processing Platform (CPP) to the user gate. Pipeline parameters (Ecoinvent database) refer to long-distance pipelines with high capacity. In addition, hotspots were also identified in the core phase: gas measurement and chromatography, gas turbine generators, and flare gas.

MAP-IO: an atmospheric and marine observatory program on board Marion Dufresne over the Southern Ocean

Abstract. This article is devoted to the presentation of the MAP-IO observation program. This program, launched in early 2021, has enabled the observation of nearly 700 d of measurements over the Indian and Southern Ocean with the equipment of 17 meteorological and oceanographic scientific instruments on board the ship Marion Dufresne. Several observational techniques have been developed to respond to the difficulties of observations on board the ship, in particular for passive remote sensing data, as well as for quasi-autonomous data acquisition and transfer. The first measurements made it possible to draw up unprecedented climatological data of the Southern Ocean regarding the size distribution and optical thickness of aerosols, the concentration of trace gases and greenhouse gases, UV, and integrated water vapor. High-resolution observations of phytoplankton in surface waters have also shown a great variability in latitude in terms of abundance and community structure (diversity). The operational success of this program and these unique scientific results together establish a proof of concept and underline the need to transform this program into a permanent observatory. The multi-year rotations over the Indian Ocean will enable us to assess the trends and seasonal variability of phytoplankton, greenhouse gases, ozone, and marine aerosols in a sensitive and poorly documented climatic region. Without being exhaustive, MAP-IO should make it possible to better understand and assess the biological carbon pump, to study the variability of gases and aerosols in a region that is remote in relation to the main anthropogenic sources, and to monitor the transport of stratospheric ozone by the Brewer–Dobson circulation. The meteorological MAP-IO data set is publicly available at https://www.aeris-data.fr/catalogue-map-io/ (last access: 26 August 2024) (atmospheric data) and at https://doi.org/10.17882/89505 (Thyssen et al., 2022a) (phytoplankton data).

NosZ II/nosZ I ratio regulates the N2O reduction rates in the eutrophic lake sediments

Nitrous oxide (N2O) is a more potent greenhouse gas with an atmospheric lifetime of 121 years, contributing significantly to climate change and stratospheric ozone depletion. Lakes are hotspots for N2O release due to the imbalance between N2O sources and sinks. N2O-reducing bacteria are the only biological means to mitigate N2O emission, yet their roles in lakes are not well studied. This study investigated the potential for N2O reduction, keystones of typical and atypical N2O-reducing bacterial communities, and their correlations with environmental factors in the sediments of Lake Taihu through microcosm experiments, high-throughput sequencing of the nosZ gene, and statistical modeling. The results showed that potential N2O reduction rates in sediments ranged from 13.71 to 76.95 μg N2O g−1 d−1, with lower rates in December compared to March and July. Correlation analysis indicated that the nosZ II/nosZ I ratio and the trophic lake index (TLI) were the primary factors influencing N2O reduction rates and N2O-reducing bacterial community structures. The genera Pseudogulbenkiania and Ardenticatena were identified as the most abundant typical and atypical N2O-reducing bacteria, respectively, and were also recognized as the keystone taxa. Quantitative real-time PCR (qPCR) results revealed that nosZ II was more abundant than nosZ I in the sediments. Partial least squares path modeling (PLS-PM) further demonstrated that atypical N2O-reducing bacteria had significant positive effects on N2O reduction process in the sediments (p < 0.05). Overall, this study highlights the crucial ecological roles of atypical N2O-reducing bacteria in the sediments of the eutrophic lake of Taihu, underscoring their potential in mitigating N2O emissions.

Environmental life cycle assessment of corn production in tropical regions

Corn growing is an important cultural and traditional system in the Iran that has considerable environmental impacts. This study was conducted to determine the environmental effects of corn production using life cycle assessment methodology. In the present study, the data have been collected from face-to-face interviews and completing a questionnaire among corn farmers in Ilam province of Iran, in 2021. The functional unit for analysis was defined as one ton of corn produced in the region. As a result, energy efficiency, energy productivity, net energy and specific energy were equal to 4.41, 0.20 kg MJ−1, 675,379.84 MJ ha−1 and 4.88 MJ kg−1 respectively. Direct, indirect, renewable and non-renewable energies was 61.59, 38.41, 16.03 and 83.97%, respectively. In this study, the amount of global warming potential per ton of product produced is estimated to be 4747,505 kg CO2 equivalent. After normalization and weighting, the highest environmental pollutants are related to the marine aquatic ecotoxicity index with 225,273 kg 1,4-dichlorobenzene equivalent and the lowest pollutants are related to the depletion of ozone layer 1,19 × 10–5 kg CFC-11 equivalent. Result showed that chemical fertilizers and electricity led to the highest contaminating emissions.

Matheuristic approaches for multi-visit drone routing problem to prevent forest fires

Forest fires draw more attention as the impact of elements that threaten nature increases, such as the thinning of the ozone layer, and global warming. The prevention of forest fires is extremely important for the protection of natural life, and the provision of a healthy world to future generations. Some of the methods used for the prevention of forest fires are observation towers, unmanned aerial vehicles, images taken from satellites, and detectors. Noticing the fire as soon as it starts and intervening in the fire prevents the fire from spreading and causing major and negative consequences. The degree of fire sensitivity of forest areas may vary depending on factors such as the climate of the region, topographic structure, humidity ratio, vegetation, tree species, and density. Observing regions with high fire sensitivity more frequently than regions with low fire sensitivity will prevent the spread of fires faster by detecting them. Different from the literature, in this study, the degree of sensitivity of fire-sensitive areas are taken into account. Visit frequency is determined according to the degree of fire sensitivity. Due to the complexity of the constraints, the mathematical model can not reach the optimal solution in a short time. To solve larger problem decomposition based matheuristic approaches are proposed. Matheuristic algorithms are compared using different parameters for samples of different sizes.

Impacts of Climatic Changes and Air Pollution on Public health and Environment

Air pollution is an emerging highlight in developing countries in changing climate, it is considered one of the greatest concerns of public, individual, and environmental health. The rate of mortality and morbidity seems to increase due to air contamination. There are many types of air pollutants, some of the major air pollutants are particulate matter (PM), carbon monoxide (CO), nitrogen oxides (NOx), sulfur oxides (SOx), and lead (Pb). PM are minute suspended particles that can inhaled while breathing and cause cardiovascular and respiratory disorders, nervous system diseases, and cancer. High levels of CO inhalation cause poisoning in humans. Nitrogen oxides are latent greenhouse gases with high global warming potential and deplete the ozone layer. SOx causes intoxication when absorbed by the human body. When lead is absorbed by the human body by inhalation it may cause toxicity, chronic obstructive pulmonary disease, asthma, and lung cancer. Thereafter air pollution and changing climate lead to the spread of many infectious diseases. Hence, the way to manage this problem of air pollution is to make the public aware of impacts and management practices. The scientific and medical experts should conduct multidisciplinary research at the national and international level to sort out this problem in a sustainable way.

Relations between cyclones and ozone changes in the Arctic using data from satellite instruments and the MOSAiC ship campaign

Abstract. Large-scale meteorological events (e.g. cyclones), referred to as synoptic events, strongly influence weather predictability but still cannot be fully characterised in the Arctic region because of the sparse coverage of measurements. Due to the fact that atmospheric dynamics in the lower stratosphere and troposphere influence the ozone field, one approach to analyse these events further is the use of space-borne measurements of ozone vertical distributions and total columns in addition to conventional parameters such as pressure or wind speed. In this study we investigate the link between cyclones and changes in stratospheric ozone by using a combination of unique measurements during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) ship expedition, ozone profile and total column observations by satellite instruments (OMPS-LP, TROPOMI), and ERA5 reanalysis data. The final goal of the study is to assess whether the satellite ozone data can be used to obtain information about cyclones and provide herewith an additional value in the assimilation by numerical weather prediction models. Three special cases during the MOSAiC expedition were selected and classified for the analysis. They are one “normal” cyclone, where a low surface pressure coincides with a minimum in tropopause height, and two “untypical” cyclones, where this is not observed. The influence of cyclone events on ozone in the upper-troposphere lower-stratosphere (UTLS) region was investigated, using the fact that both are correlated with tropopause height changes. The negative correlation between tropopause height from ERA5 and ozone columns was investigated in the Arctic region for the 3-month period from June to August 2020. This was done using total ozone columns and sub-columns from TROPOMI, OMPS-LP, and MOSAiC ozonesonde data. The greatest influence of tropopause height changes on ozone contour levels occurs at an altitude between 10 and 20 km. Moreover, the lowering of the 250 ppb ozonopause (at about 11 km altitude) below 9 km was used to detect cyclones using OMPS-LP ozone observations. The potential of this approach was demonstrated in two case studies where the boundaries of cyclones could be determined using ozone observations. The results of this study can help improve our understanding of the relationship between cyclones, tropopause height, and ozone in the Arctic and demonstrate the usability of satellite ozone data in addition to the conventional parameters for investigating cyclones in the Arctic.

Problematic issues of international legal regulation of the use, reproduction and protection of specially protected flora

The article is devoted to the study of some aspects of international legal regulation of the use, reproduction and protection of specially protected flora. Unfortunately, the expansion of the scope of international environmental law does not adequately reflect the state of the environment. The problems of climate change, the destruction of the Earth’s ozone layer, deforestation, desertification, conservation of migratory species of animals, fish and birds, transboundary water and air pollution, natural disasters, preservation of biodiversity and the natural heritage of mankind, which directly affect flora, have now become global. Everyone in the world is interested in a high-quality environment, careful use of natural resources and fair distribution of income from natural resources. However, the current international environmental law is not a sufficiently perfect tool to address the problem of regulating the use, reproduction and protection of specially protected plant species. In particular, it is not properly systematised and codified. The author analyses that the problem identified in the article is not solved by the existing international legal acts of a general nature - the Stockholm Declaration on the Environment, the Rio Declaration on Environment and Development (1992), and the World Charter for Nature (1982). These documents are not legally binding and are not systemically important for international environmental law. Other international environmental legal acts are not universal. They were adopted at different times, by different actors, and contain many gaps. Often, the documents are declarative, contradictory and not based on the modern international legal doctrine of environmental law development.

Reporting of gridded ammonia emission and assessment of hotspots across India: A comprehensive study of 24 anthropogenic sources

Ammonia (NH3) acts as a key precursor of the particulate matter, could reduce visibility, deplete stratospheric ozone, and trigger perturbation in ecosystems. Being an agrarian country with a large livestock population and uncontrolled fertilizer application, India could be accountable as a major stakeholder of global NH3 emissions. This study developed a comprehensive gridded (0.1° x 0.1°) ammonia inventory for India considering 24 types of sources. The total NH3 emission is estimated to be 10.54 Tg/yr in 2022, where synthetic fertilizer application accounts for ∼47 % followed by livestock (∼34 %). Minor unattended sectors such as biomass burning, agricultural soil, human excrement, waste disposal, etc. contribute 0.68 Tg/yr, 0.32 Tg/yr, 0.3 Tg/yr, and 0.14 Tg/yr, respectively. The overall uncertainty of the inventory ranges around ± 55 %. These emission datasets are essential for atmospheric chemistry models and could be a crucial tool for policymakers to combat ammonia pollution.

Rancang Bangun Green Portable Cooler Box

Freon is one of the refrigerants used in refrigeration systems. The refrigeration system has a very important role, namely to preserve food ingredients so that food can last longer. The use of freon is not only used in ships but is widely found in home appliances in refrigeration systems used in freezers, air conditioners, refrigerators, and dispensers. If more freon is used, the negative impact that arises is greater, namely the depletion of the ozone layer and global warming which can have a bad influence on health, the life of living things and the environment. The purpose of this researcher is to create a tool to reduce the negative impact of freon use, namely by using peltier as a cooling medium with environmentally friendly thermoelectric modules. This study uses trial and error methods. Where the trial process is carried out by turning on one of the working push buttons and observing the temperature value. Then it is processed by the control system, namely Arduino Mega which will later provide a PWM output signal to the IRF540 mosfet when the output temperature value is in line with the reference value and vice versa. The test of this tool was carried out by comparing measurements between the author's prototype tool and the standard measuring tool, namely the digital thermometer. Based on the test results, this device can produce a minimum temperature of 140C at 30-minute intervals without any media. The trial using 330ml bottled water can reach a temperature of 170C within 30 minutes in the cooler box. This tool is also equipped with an automatic monitoring system using a PWM signal in the form of a change in fan speed, which is 255 RPS maximum speed and when getting a PWM signal it changes to 50 RPS. The percentage of errors resulting from the comparison of standard measuring instruments and sensor values had the highest and lowest percentages of 2.37% and 0.84% in cold dispersion conditions without charge. Then the highest and lowest error percentages were 1.69% and 0.72% in the state of containing a load of 1 330ml mineral bottle. This ptototype uses data recording using Micro-SD as a data logger.

Perspective on Theoretical and Experimental Advances in Atmospheric Photochemistry.

Research that explores the chemistry of Earth's atmosphere is central to the current understanding of global challenges such as climate change, stratospheric ozone depletion, and poor air quality in urban areas. This research is a synergistic combination of three established domains: earth observation, for example, using satellites, and in situ field measurements; computer modeling of the atmosphere and its chemistry; and laboratory measurements of the properties and reactivity of gas-phase molecules and aerosol particles. The complexity of the interconnected chemical and photochemical reactions which determine the composition of the atmosphere challenges the capacity of laboratory studies to provide the spectroscopic, photochemical, and kinetic data required for computer models. Here, we consider whether predictions from computational chemistry using modern electronic structure theory and nonadiabatic dynamics simulations are becoming sufficiently accurate to supplement quantitative laboratory data for wavelength-dependent absorption cross-sections, photochemical quantum yields, and reaction rate coefficients. Drawing on presentations and discussions from the CECAM workshop on Theoretical and Experimental Advances in Atmospheric Photochemistry held in March 2024, we describe key concepts in the theory of photochemistry, survey the state-of-the-art in computational photochemistry methods, and compare their capabilities with modern experimental laboratory techniques. From such considerations, we offer a perspective on the scope of computational (photo)chemistry methods based on rigorous electronic structure theory to become a fourth core domain of research in atmospheric chemistry.

Global Warming in Interaction with Domestic and Foreign Investment: The Indian Case Study

Human actions have a substantial impact on the global environment. The depletion of the ozone layer due to the use of chlorofluorocarbons and the threat of global warming due to the accumulation of "greenhouse gases," carbon dioxide and methane that is released in agriculture, energy production, and transportation are few prominent illustrations of damages to the environment. The advent of these unprecedented repercussions of human activities on a global scale eventually directs to a complex economic policy in the world. Hence, the policies to promote economic growth, equity, trade, and technological change to have a significant impact on the global environmental scenario. Purpose: In this respect, the current study concentrates on the financial activities by a country, specifically, India, in relation to the global warming. The major financial activities in a country are based on domestic as well as foreign investment. The source of the domestic financial investment activities, known as Domestic Investment (DI), considered here are investment in plant, machinery, and equipment purchase. While the source of foreign investment is specified as Foreign Direct Investment (FDI). Methodology: The study applies Auto Regressive Distributed Lag (ARDL) model to find the co-integration between the three variables. Further, the long run impact of domestic investment and short run impact of FDI on carbon dioxide emission are found to be present. Finding: The study finds significant environmental impact of domestic and foreign investment in India. Implication: Further, the study provides important policy implication by suggesting reducing the usage of carbon emission through fossil fuel to improve long run sustainable development in India.

Effects of polyethylene microplastics on CHCl3 and CHBr3 fluxes and microbial community in temperate salt marsh soil

Microplastics (MPs) affect the carbon cycle in coastal salt marsh soils. However, studies on their effects on CHCl3 and CHBr3, which are volatile halohydrocarbons that can damage the ozone layer, are lacking. In this study, indoor simulation experiments were conducted to explore the effects of MPs invasion on the source and sink characteristics of soil CHCl3 and CHBr3. The results showed that different concentrations of polyethylene (PE)-MPs promoted CHCl3 and CHBr3 emissions. Emission peaks of the two gases appeared on days 3 and 15 during the culture cycle. CHCl3 and CHBr3 fluxes were mainly affected by soil physicochemical properties and microbial communities. PE-MPs caused changes in soil properties, microorganisms, and related functional genes. Soil total organic carbon, which was significantly and positively correlated with CHCl3. Dissolved organic matter, which was one of the main factors affecting CHBr3, its relative content increased after the addition of PE-MPs. The abundances of Methylocella and Dehalococcoides, which mediate dechlorination reduction, decreased with the addition of PE-MPs. The addition of PE-MPs also significantly varied the abundance of ctrA, which controls dechlorination in soil microorganisms. The gene pceA greatly influenced CHCl3 emissions. In addition, CHBr3 flux was influenced by the interactions between sediment redox and microbial co-metabolic reactions under the control of genes such as TC.FEV.OM and soxB. This study provides theoretical and data support for the source and sink characteristics of volatile halohydrocarbons in coastal salt marshes and highlights the environmental hazards of MPs.

Environmental Policies and Countermeasures for the Phase-Out of Ozone-Depleting Substances (ODSs) over the Last 30 Years: A Case Study in Taiwan

It is well established that the reaction cycles involving some halogenated alkanes (so-called ozone-depleting substances—ODSs) contribute to the depletion of ozone in the stratosphere, prompting the Montreal Protocol (initially signed in 1987), and later amendments. The Protocol called for the scheduled phase-out of ODSs, including chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), carbon tetrachloride (CCl4), halon, methyl chloroform (CH3CCl3), methyl chloride (CH3Cl), and even hydrofluorocarbons (HFCs). In view of the urgent importance of ozone layer protection to the global ecological environment, the Taiwanese government has taken regulatory actions to reduce ODS consumption since 1993, through the joint venture of the central competent authorities. Under the government’s regulatory requirements, and the industry’s efforts to adopt both alternatives to ODSs and abatement technologies, the phase-out of some ODSs (i.e., CFCs, CCl4, halon, and CH3CCl3) was achieved prior to 2010. The consumption of HCFCs and methyl chloride has significantly declined over the past three decades (1993–2022). However, HFC emissions indicated a V-type variation during this period. Due to local production and extensive use of HFCs in Taiwan, the country’s emissions increased from 663 kilotons of carbon dioxide equivalents (CO2eq) in 1993 to 2330 kilotons of CO2eq in 2001, and then decreased to 373 kilotons of CO2eq in 2011. Since then, the emissions of HFCs largely used as the alternatives to ODSs showed an upward trend, increasing to 1555 kilotons of CO2eq in 2022. To be in compliance with the Kigali Amendment (KA-2015) to the Montreal Protocol for mitigating global warming, the Taiwanese government has taken regulatory actions to reduce the consumption of some HFC substances with high global warming potential (GWP) under the authorization of the Climate Change Response Act in 2023, aiming at an 80% reduction by 2045 of the baseline consumption in 2024.