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Nitrogen budgets in Japan from 2000 to 2015: Decreasing trend of nitrogen loss to the environment and the challenge to further reduce nitrogen waste النص الكامل
2021
Hayashi, Kentaro | Shibata, Hideaki | Oita, Azusa | Nishina, Kazuya | Ito, Akihiko | Katagiri, Kiwamu | Shindo, Junko | Winiwarter, Wilfried
The benefits of the artificial fixation of reactive nitrogen (Nr, nitrogen [N] compounds other than dinitrogen), in the form of N fertilizers and materials are huge, while at the same time posing substantial threats to human and ecosystem health by the release of Nr to the environment. To achieve sustainable N use, Nr loss to the environment must be reduced. An N-budget approach at the national level would allow us to fully grasp the whole picture of Nr loss to the environment through the quantification of important N flows in the country. In this study, the N budgets in Japan were estimated from 2000 to 2015 using available statistics, datasets, and literature. The net N inflow to Japanese human sectors in 2010 was 6180 Gg N yr⁻¹ in total. With 420 Gg N yr⁻¹ accumulating in human settlements, 5760 Gg N yr⁻¹ was released from the human sector, of which 1960 Gg N yr⁻¹ was lost to the environment as Nr (64% to air and 36% to waters), and the remainder assumed as dinitrogen. Nr loss decreased in both atmospheric emissions and loss to terrestrial water over time. The distinct reduction in the atmospheric emissions of nitrogen oxides from transportation, at −4.3% yr⁻¹, was attributed to both emission controls and a decrease in energy consumption. Reductions in runoff and leaching from land as well as the discharge of treated water were found, at −1.0% yr⁻¹ for both. The aging of Japan's population coincided with the reductions in the per capita supply and consumption of food and energy. Future challenges for Japan lie in further reducing N waste and adapting its N flows in international trade to adopt more sustainable options considering the reduced demand due to the aging population.
اظهر المزيد [+] اقل [-]Stocks, flows and emissions of DBDPE in China and its international distribution through products and waste النص الكامل
2019
Shen, Kaihui | Li, Li | Liu, Junzhou | Chen, Chengkang | Liu, Jianguo
Decabromodiphenyl ethane (DBDPE) is an alternative to the commercial decabromodiphenyl ether (deca-BDE) mixture but has potentially similar persistence, bioaccumulation potential and toxicity. While it is widely used as a flame retardant in electrical and electronic equipment (EEE) in China, DBDPE could be distributed globally on a large scale with the international trade of EEE emanating from China. Here, we performed a dynamic substance flow analysis to estimate the time-dependent mass flows, stocks and emissions of DBDPE in China, and the global spread of DBDPE originating in China through the international trade of EEE and e-waste. Our analysis indicates that, between 2006 and 2016, ∼230 thousand tonnes (kt) of DBDPE were produced in China; production, use and disposal activities led to the release of 196 tonnes of DBDPE to the environment. By the end of 2016, ∼152 kt of the DBDPE produced resided in in-use products across China. During the period 2000–2016, ∼39 kt of DBDPE were exported from China in EEE products, most of which (>50%) ended up in North America. Based on projected trends of China's DBDPE production, use and EEE exports, we predict that, by 2026, ∼74 and ∼14 kt of DBDPE originating in China will reside in in-use and waste stocks, respectively, in regions other than mainland China, which will act as long-term emission sources of DBDPE worldwide. This study discusses the considerable impact of DBDPE originating in China and distributed globally through the international trade of EEE; this is projected to occur on a large scale in the near future, which necessitates countermeasures.
اظهر المزيد [+] اقل [-]Invasive species in the Northeastern and Southwestern Atlantic Ocean: A review النص الكامل
2017
Castro, Maria Cecilia T de | Fileman, Timothy W. | Hall-Spencer, Jason M
The spread of non-native species has been a subject of increasing concern since the 1980s when human-mediated transportation, mainly related to ships' ballast water, was recognized as a major vector for species transportation and spread, although records of non-native species go back as far as 16th Century. Ever increasing world trade and the resulting rise in shipping have highlighted the issue, demanding a response from the international community to the threat of non-native marine species. In the present study, we searched for available literature and databases on shipping and invasive species in the North-eastern (NE) and South-western (SW) Atlantic Ocean and assess the risk represented by the shipping trade between these two regions. There are reports of 44 species associated with high impacts for the NE Atlantic and 15 for the SW Atlantic, although this may be an underestimate. Vectors most cited are ballast water and biofouling for both regions while aquaculture has also been a very significant pathway of introduction and spread of invasive species in the NE Atlantic. Although the two regions have significant shipping traffic, no exchange of invasive species could be directly associated to the shipping between the two regions. However, it seems prudent to bring the exchange of ballast water between the two regions under control as soon as possible.
اظهر المزيد [+] اقل [-]Shipping emission inventories in China's Bohai Bay, Yangtze River Delta, and Pearl River Delta in 2018 النص الكامل
2020
Wan, Zheng | Ji, Shaojie | Liu, Yati | Zhang, Qiang | Chen, Jihong | Wang, Qin
Pollutant emissions from ships could increase with expanding international trade and shipping fleet size, posing a severe but often overlooked threat to public health. China houses the three biggest port clusters in the world: the Bohai Bay (BB), the Yangtze River Delta (YRD), and the Pearl River Delta (PRD) and must combat pollutant emissions. This study examines the emissions of key pollutants (i.e., NOX, PM₁₀, PM₂.₅, HC, CO, SOX, CO₂, NMVOC, and CH₄) utilizing a bottom-up methodology with the aid of automatic identification system data. Our results show that among the three regions studied, ships in the YRD produce the most emissions, accounting for 47.84% of the combined total emissions in 2018. We evaluate the emissions from different ship types, operation modes, and discharge equipment. Container ships account for ~50% of all emissions, which are mainly generated during the cruising phase. Different power sources produce varying levels of pollutants owing to power, load, and discharge variations. In addition, ship emissions have seasonal characteristics, which are reflected by the decline trend recorded in February, July, August, and December. This baseline dataset could aid comparisons with historic or future emission data and help establish regulatory actions to improve air quality.
اظهر المزيد [+] اقل [-]Approaches to reduce noise from ships operating in important killer whale habitats النص الكامل
2019
Williams, Rob | Veirs, Scott | Veirs, Val | Ashe, Erin | Mastick, Natalie
Shipping is key to global trade, but is also a dominant source of anthropogenic noise in the ocean. Chronic noise from ships can affect acoustic quality of important whale habitats. Noise from ships has been identified as one of three main stressors–in addition to contaminants, and lack of Chinook salmon prey–in the recovery of the endangered southern resident killer whale (SRKW) population. Managers recognize existing noise levels as a threat to the acoustical integrity of SRKW critical habitat. There is an urgent need to identify practical ways to reduce ocean noise given projected increases in shipping in the SRKW's summertime critical habitat in the Salish Sea. We reviewed the literature to provide a qualitative description of mitigation approaches. We use an existing ship source level dataset to quantify how some mitigation approaches could readily reduce noise levels by 3–10 dB.
اظهر المزيد [+] اقل [-]Spatial distribution and enrichment assessment of heavy metals in surface sediments from Baixada Santista, Southeastern Brazil النص الكامل
2016
Kim, Bianca Sung Mi | Salaroli, Alexandre Barbosa | Ferreira, Paulo Alves de Lima | Sartoretto, Juliê Rosemberg | Mahiques, Michel Michaelovich de | Figueira, Rubens Cesar Lopes
The Baixada Santista, besides being an important estuarine system, is responsible for most of the international trade and economic development in the region because of the Santos Port and the Cubatão Industrial Complex. The aim of this study is to assess heavy metal contamination of the Santos São Vicente Estuary using enrichment factors (EFs) and sediment quality guidelines (SQGs). Thus, superficial sediment samples were subjected to acid digestion and analyzed (Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sc, V, and Zn) by inductively coupled plasma optical emission spectrometry (ICP-OES). The results indicated an absence of contamination, with the EFs indicating moderate enrichment. As and Pb presented higher enrichment probably due to the natural processes of weathering and sedimentation, and the influence of human activity. This conjoint analysis showed that potentially polluting activities are of concern as the highest values converge near the Cubatão Industrial Complex, which correspond to intense urbanization and industrial activity.
اظهر المزيد [+] اقل [-]Feasibility of national nitrogen balances
1998
Slak, M.F. | Commagnac, L. | Lucas, S. (ENITA de Bordeaux, Laboratoire Sols et Paysages (France))
What drives the export-related carbon intensity changes in China? Empirical analyses from temporal–spatial–industrial perspectives النص الكامل
2022
Shi, Qiaoling | Zhao, Yuhuan | Zhong, Chao
This study aims to explore the driving determinants on the export-related carbon intensity (ECI) of China, to better understand the impact of international trade on climate change governance and facilitate China’s carbon intensity mitigation goals. First, China’s ECI evolution and its gaps with the USA and India are measured during 2002–2014. Then, the main drivers of China’s ECIvert study further discusses the influencing factors of ECI in the manufacturing industry using the environmental-extended STIRPAT model and GMM method. The results show that (1) China’s overall ECI increases from 1.50 Kg/US$ in 2002 to 1.92 Kg/US$ in 2005 and then decreases to 1.27 Kg/US$ in 2014. The ECI of the manufacturing industry is significantly higher than that of the agriculture and service industry. China’s ECI gap with the USA is greater than that with India, and both show a downward trend. (2) Carbon emission coefficient is the domain factor to reduce China’s ECI during 2002–2014; the effects of the value-added coefficient, input–output structure, and final demand are limited. The input structure dominantly expands China’s ECI gaps both with the USA and India, followed by the value-added coefficient. The carbon emission coefficient enlarges the ECI gap with the USA while reduces that with India. (3) Industrial productivity and value-added rate are negatively correlated with ECI in the manufacturing industry, while per capita capital stock plays the opposite role. The positive correlation between energy intensity and CIE becomes significant after distinguishing technology heterogeneity. In contrast to the non-tech-intensive manufacturing industry, the increase of backward GVCs participation of tech-intensive ones will reduce the ECI. The threshold effect of backward GVCs participation exists in the whole manufacturing industry. Targeted ECI reduction policy implications are suggested.
اظهر المزيد [+] اقل [-]Environmental R&D and trade-adjusted carbon emissions: evaluating the role of international trade النص الكامل
2022
Jiang, Shu | Chishti, Muhammad Zubair | Rjoub, Husam | Rahim, Syed
In the contemporary era, it is evident that consumption-based carbon emissions (CCO2e), adjusted for international trade, are a more accurate and robust measure of environmental pollution than production-based emissions. Therefore, many studies have focused on exploring the determinants of CCO2e; however, the literature could not yet discern environment-related R&D budget (ERRD) and political risk index (PRI) as a new driver. To fill this gap, the current paper aims to divulge the dynamic effects of ERRD and PRI on CCO2e while taking imports, exports, and GDP as control regressors. To do so, the G7 nations’ data from 1990 to 2020 is utilized, and several advanced econometric tests and techniques are deployed to tackle the advanced issues (i.e., cross-section dependence, heterogeneity, and endogeneity) in econometrics. The CS-ARDL estimates suggest that PRI and ERRD significantly lessen the environmental quality by disrupting the detrimental effects of CCO2e. Likewise, the rise in exports possesses a negative association with the ratio of CCO2e. However, CCO2e significantly tends to surge on account of an increase in GDP and imports. GDP squared exhibits the negative link with CCO2e, confirming the EKC hypothesis in G7 nations. Besides, the AMG technique and causality test validate the robustness of our findings. In addition, the policies related to CCO2e by authorities will take approximately more than a year to absorb their effects.
اظهر المزيد [+] اقل [-]The role of economic freedom and clean energy in environmental sustainability: implication for the G-20 economies النص الكامل
2022
Alola, Andrew Adewale | Alola, Uju Violet | Akdag, Saffet | Yıldırım, Hakan
With the increasing challenge of attaining sustainable balance in socioeconomic-ecosystem activities, the aspects of the global goals are continously being harnesed in order to ensure a sustainable interaction. As an alliance of the United Nations, the G-20 member countries have not only committed to attaining the Sustainable Development Goals 2030, the alliance body has further fostered frameworks that are targeted at advancing global economic and environmental sustainability. Within this context, the current study examined the environmental sustainability effects arising from the economic freedom prowess in the panel of the G-20 economies over the period 2000–2016. Among the sparse studies, the study employed the indices of economic freedom: freedom to trade internationally, regulation, sound money, legal framework, and property right and alongside the real income and renewable energy consumption as explanatory indicators. With the result of the difference- and two-step system GMM (generalized method of moments), the legal system and property right, sound money, freedom to international trade, and regulatory efficiency are detrimental to the panel countries’ environmental quality. Although this is likely to be untrue for countries that have advanced their climate actions and especially the Sustainable Development Goals (SDGs) 2030, it suggests a dearth in the SDGs achievement among the developing and emerging economies. Moreover, it probably shows the depth of traditional or business-as-usual practices (such as the lack of sustainable economic and environmental practices) and the socioeconomic system that are obtainable in most of the developing and emerging economies. Thus, the study put forward tangible policies that are essential for governance and toward attaining desirable country-specific SDGs.
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