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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
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.
显示更多 [+] 显示较少 [-]Stocks, flows and emissions of DBDPE in China and its international distribution through products and waste
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.
显示更多 [+] 显示较少 [-]Approaches to reduce noise from ships operating in important killer whale habitats
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.
显示更多 [+] 显示较少 [-]Spatial distribution and enrichment assessment of heavy metals in surface sediments from Baixada Santista, Southeastern Brazil
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.
显示更多 [+] 显示较少 [-]Shipping emission inventories in China's Bohai Bay, Yangtze River Delta, and Pearl River Delta in 2018
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.
显示更多 [+] 显示较少 [-]Invasive species in the Northeastern and Southwestern Atlantic Ocean: A review
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.
显示更多 [+] 显示较少 [-]Feasibility of national nitrogen balances
1998
Slak, M.F. | Commagnac, L. | Lucas, S. (ENITA de Bordeaux, Laboratoire Sols et Paysages (France))
Consumption-based carbon emissions, trade, and globalization: an empirical study of Bolivia
2022
Kirikkaleli, Dervis | Oyebanji, Modupe Oluyemisi
The consequences of global trade on carbon dioxide emissions have been mainly investigated in several empirical papers; however, the consumption-based carbon emissions adjusted for international trade have been lacking in the literature. This empirical research seeks to address this gap by using consumption-based carbon emissions adjusted for trade in the case of Bolivia. Research over the years shows that Bolivia has had a consistent negative trade deficit which suggests that there might be a rise in consumption-based emission in this area in the present and the future. It also indicates that considerable emissions are attributable to the consumption of commodities and services transferred to Bolivia, which is beyond its control. Many studies, however, have delved into the production-based carbon emission for Bolivia. However, the consumption-based carbon emission adjusted for international trade has been missing in the case of Bolivia. Meanwhile, failure to recognize these emissions related to international trade produces an incomplete picture of the emissions triggers and the effectiveness of action to lessen emissions in this area. Hence, this study attempts to fill the gap. The impact of exports and imports are analyzed separately for 1970 to 2018. The empirical analysis confirms a negative effect of exports and GDP on consumption-based carbon emissions. In comparison, imports and globalization demonstrate a favorable impact on consumption-based carbon emissions and show their statistical significance. This study suggests that the Bolivia government should be cautious on policies targeted at increasing growth as this could be harmful to the sustainability of the environment.
显示更多 [+] 显示较少 [-]International trade, CO2 emissions, and re-examination of “Pollution Haven Hypothesis” in China
2022
Wu, Ran | Ma, Tao | Chen, Dongxu | Zhang, Wenxi
We use input-output analysis and Levinson’s structural decomposition method to measure China’s CO₂ emissions under the no-trade hypothesis, to calculate how international trade affects China’s emissions. We also analyze the driving factors of the difference between hypothetical no-trade CO₂ emissions and actual emissions and discuss the existence of “Pollution Haven Hypothesis” (PHH) in China. The results show that (1) from 2000 to 2017, the hypothetical no-trade CO₂ emissions are 2.43–14.67% lower than actual emissions. The scale effect is the main cause of this difference, while the composition effect fluctuates and has little impact. (2) Although exports make other economies’ CO₂ emissions transfer to China, imports also help avoid China’s emissions from some carbon-intensive sectors. (3) International trade has little impact on the cleanliness of China’s industry composition. The no-trade industry composition is slightly cleaner than the actual one before 2010, after which trade improves the cleanliness of industry composition to a small extent. PHH is invalid for China in recent years, and results for most developing countries do not support PHH. (4) The relationship between no-trade effects and income per capita for all the economies does not also support PHH. Most economies reduce emissions, and their industry compositions are cleaner because of trade, regardless of their development degree. Trade will not severely influence China’s future emission reduction, and improving the cleanliness of carbon-intensive sectors should be paid more attention to.
显示更多 [+] 显示较少 [-]Influence of carbon tariffs on China’s export trade
2022
Sheng, Yijie | Wang, Qian
The database of the Global Trade Analysis Project (GTAP) and its energy–environmental model, known as GTAP-E, are used in this study to simulate the effect of the simultaneous and separate carbon tariff impositions of EU, the USA, and Japan on the export and export structure in China. Simulation results show that the carbon tariff impositions of developed countries on China will decrease the export to EU, the USA, and Japan but increase the export of China to other countries associated with the trade diversion in China. The USA and EU impose carbon tariffs on China, which will have a serious impact on China’s export trade, especially for the export trade of energy-intensive industries. When Japan imposes carbon tariff on the exports of China, the positive influence on the export trade is weaker compared to the situation that the USA and EU imposed on China. Furthermore, imposing carbon tariffs on China will improve its trade structure; promote its agriculture, petroleum, and natural gas exploration and electricity industries; reduce its export trade volume of coal mining, petroleum products, and energy-intensive and other industries; decrease the export trade share of energy-intensive industries; and increase the export trade share and services of other industries. In this regard, China should reduce the carbon content of export products initiatively. On the one hand, China can solve this problem by levying carbon tax, developing emerging industries, and strengthening the research and development of low-carbon technologies. On the other hand, China should actively participate in the formulation of international standards of carbon tariff and become a participant in the international emission reduction rules in the field of climate change.
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