Chemical Exports Research Articles

Differential Spatiotemporal Patterns of Major Ions and Dissolved Organic Carbon Variations from Non-Permafrost to Permafrost Arctic Basins: Insights from the Severnaya Dvina, Pechora and Taz Rivers

The Arctic river basins, among the most sensitive regions to climate warming, are experiencing rapid temperature rise and permafrost thawing that profoundly affect their hydrological and hydrochemical systems. However, our understanding of chemical export from Arctic basins to oceans remains limited due to scarce data, particularly in permafrost-dominated regions. This study examines the spatiotemporal variations and seasonal dynamics of major ions (Na+, K+, Mg2+, Ca2+, Cl−, SO42−) and dissolved organic carbon (DOC) concentrations across three river basins with varying permafrost extents: the Severnaya Dvina (2006–2008, 2012–2014), the Pechora (2016–2019) and the Taz Rivers (2016–2020). All the data were sourced from published Chemical Geological researches and were taken from Mendeley and PANGAEA datasets. Our results showed that DOC concentrations ranged from 1.75 to 26.40 mg/L, with the Severnaya Dvina River exhibiting the highest levels of DOC concentrations, alongside significantly elevated ion concentrations compared to the other two basins. A positive correlation was observed between DOC concentrations and river discharge, with peaks during the spring flood and summer baseflow due to leaching processes. The Severnaya Dvina and Pechora Rivers exhibited the highest DOC values during the spring flood, reaching 26.40 mg/L and 8.07 mg/L, respectively. In contrast, the Taz River had the highest runoff during the spring flood season, but the DOC concentration reached its highest value of 11.69 mg/L in the summer. Specifically, a 1% increase in river discharge corresponded to a 1.25% rise in DOC concentrations in the Severnaya Dvina River and a 1.04% increase in the Pechora River, while there was no significant correlation between runoff and DOC concentrations in the Taz River. Major ion concentrations demonstrated a negative correlation with river discharge, remaining relatively high during winter low-flow period. A robust power-law relationship between river discharge and concentration of DOC and major ions was observed, with distinct variations across the three river basins depending on permafrost extent. The Pechora and Taz Rivers, characterized by extensive permafrost, exhibited increasing trends in river discharge and DOC concentrations, accompanied by decreasing major ion concentrations, whereas the non-permafrost-dominated Severnaya Dvina River basin showed the opposite pattern. The Taz River, with the most extensive permafrost, also displayed a delayed DOC peak and more complex seasonal ion concentration patterns. These findings highlight the importance of varying permafrost extents and their implications for water quality and environmental protection in these vulnerable regions.

German chemical exports decline

German chemical exports decline

Soil water percolation and nutrient fluxes as a function of topographical, seasonal and soil texture variation in Central Amazonia, Brazil

AbstractUnderstanding soil water dynamics and transport of nutrients is challenging in tropical rainforests due to the uniqueness of several properties related to soils, vegetation and seasonality that make relating patterns found in temperate environments to tropical sites difficult. We address the need for better edaphic characterization in tropical environments by investigating soil water percolation rates and chemistry across topographic, soil texture and seasonal gradients in a mature tropical rainforest in Central Amazonia, Brazil. We utilized a passive wick flux meter (e.g., drainage lysimeter) to directly measure real‐time percolation fluxes at 60‐cm depth, and to sample a suite of chemical species across plateau, slope and valley topographic positions. We found percolation flux volume and chemical exports generally increase with decreasing elevation and clay content, which was lowest in the valley. Daily percolation flux was observed to be 2.39 ± 0.44 in plateau, 3.01 ± 0.50 in slope and 6.16 ± 0.83 mm in valley. Most solutes were present in small amounts of <1 mg L−1, such as PO₄3−, Fe2+/Fe3+ and Mn2+; however, NO3− concentrations were >20 mg L−1, even exceeding 100 mg L−1 in the valley. Based on additional isotopic analysis, we speculate high NO3− concentrations are partially an artefact of root decomposition following installation of the flux meters. The empirical relationships we show among percolation volume and nutrient exports under varying topographies and soil textures can improve Earth System Model performance by better constraining ecohydrological relationships to nutrient fluxes, which can in‐turn better illuminate the important factors that govern their behaviour.

Causes of coastal waters pollution with nutrients, chemicals and plastics worldwide

Worldwide, coastal waters contain pollutants such as nutrients, plastics, and chemicals. Rivers export those pollutants, but their sources are not well studied. Our study aims to quantify river exports of nutrients, chemicals, and plastics to coastal waters by source and sub-basin worldwide. We developed a new MARINA-Multi model for 10,226 sub-basins. The global modelled river export to seas is approximately 40,000 kton of nitrogen, 1,800 kton of phosphorous, 45 kton of microplastics, 490 kton of macroplastics, 400 ton of triclosan and 220 ton of diclofenac. Around three-quarters of these pollutants are transported to the Atlantic and Pacific oceans. Diffuse sources contribute by 95–100 % to nitrogen (agriculture) and macroplastics (mismanaged waste) in seas. Point sources (sewage) contribute by 40–95 % to phosphorus and microplastics in seas. Almost 45 % of global sub-basin areas are multi-pollutant hotspots hosting 89 % of the global population. Our findings could support strategies for reducing multiple pollutants in seas.

Changing structure of India’s exports with Africa: Where do the technology-intensive exports stand?

The present study is an endeavour to document the pattern of comparative advantage and structural changes of Indian exports with Africa with the help of revealed comparative advantage index and the constant market share model for the period 1980–2021. The results indicate that India possesses a comparative advantage in a large number of export products to markets in Africa. However, most of these exports belong to the category of low-tech and resource-based goods. Considering its abundant labour, it is to be expected for India to have a comparative advantage in these low-skilled and labour-intensive traditional exports. The commodities with maximum advantage in the African market are medicinal and pharmaceutical products followed by sugar, sugar preparations, and honey. In the category of technology-intensive products, India has strengthened its market power only in the export of organic chemicals and dyes, and colouring materials.

Beaver dams overshadow climate extremes in controlling riparian hydrology and water quality

Hydrologic extremes dominate chemical exports from riparian zones and dictate water quality in major river systems. Yet, changes in land use and ecosystem services alongside growing climate variability are altering hydrologic extremes and their coupled impacts on riverine water quality. In the western U.S., warming temperatures and intensified aridification are increasingly paired with the expanding range of the American beaver—and their dams, which transform hydrologic and biogeochemical cycles in riparian systems. Here, we show that beaver dams overshadow climatic hydrologic extremes in their effects on water residence time and oxygen and nitrogen fluxes in the riparian subsurface. In a mountainous watershed in Colorado, U.S.A., we find that the increase in riparian hydraulic gradients imposed by a beaver dam is 10.7–13.3 times greater than seasonal hydrologic extremes. The massive hydraulic gradient increases hyporheic nitrate removal by 44.2% relative to seasonal extremes alone. A drier, hotter climate in the western U.S. will further expand the range of beavers and magnify their impacts on watershed hydrology and biogeochemistry, illustrating that ecosystem feedbacks to climate change will alter water quality in river systems.

Geochemical characteristics of strontium isotopes in a coastal watershed: implications for anthropogenic influenced chemical weathering and export flux.

Coastal watershed are essential in transporting dissolved loads from terrestrial biogeochemical process of surface environment to the adjacent oceans. The solute chemistry of coastal river water contains significant information about environmental processes under the impact of both natural lithology and anthropogenic pressure. In this study, strontium (Sr) isotopes and water chemistry data of the Jiulongjiang (JLJ) river water were analyzed in detail to trace the contribution of bedrock weathering, and quantify Sr flux to the East China Sea (ECS). The dissolved Sr contents ranged 0.07–0.90 μmol L−1 and greatly fluctuated where tributaries encountered, and 87Sr/86Sr values relatively fluctuated between 0.7140 and 0.7514. Silicate weathering was identified to be the predominant contribution of riverine dissolved loads. Strontium flux to the ocean in dry season was estimated to be 689.2 tons per year, implying an essential influence on oceanic strontium evolution. In accordance with forward model, the silicate weathering rate and CO2 consumption rate were 55.7 tons km−2 per year and 16.9 × 105 mol km−2 per year, respectively, slightly higher than world average. Considering anthropogenic impacts alongside the river, the integrated effect of lower runoff and longer retention time of river water in dry season may aggravate weathering processes. Although CO2 sink by silicate weathering in JLJ seems less than the sink in world’s central reservoirs, it should still be taken into consideration for coastal carbon budget. These findings highlight the use of geochemical characteristics of strontium and its isotopes in identifying weathering process and output flux to the ocean, which provides basic data for sustainable coastal water resource management.

The effects of Indonesia’s technical barriers to trade on manufacturing exports: an empirical analysis using the pseudo-Poisson maximum likelihood method

PurposeThe purpose of this study is to investigate the effects of Indonesia’s technical barriers to trade (TBT) on manufacturing exports.Design/methodology/approachThis study uses the UNCTAD database to calculate the coverage ratio and frequency index of TBTs, which represent the restrictiveness of TBTs on imports. The effects of TBTs are estimated using the gravity model (Tinbergen, 1962) and the pseudo-Poisson maximum likelihood methodology (Santos Silva and Tenreyro, 2006, 2011).FindingsAn estimation on the manufacturing sector shows that TBT reduces Indonesia’s manufacturing exports. However, the effect of TBT is different in disaggregated manufacturing sector. TBT is found to reduce exports of chemicals and transportation but increase exports of metal and textiles. This finding supports the empirical evidence that TBT can create trade-impeding and demand-enhancing effects on trade flows. The negative effect of TBT on chemical and transportation exports implies that the cost of compliance is higher than the increasing demand rate. This finding suggests the need for policy evaluation and improvements for restrictive TBT. As Indonesia is still highly dependent on imported inputs, restrictive TBT can potentially reduce the productivity of the Indonesian manufacturing sector.Originality/valueThis study aims to investigate the effects of TBT in Indonesia, as a manufacturing-based economy that relies heavily on imported intermediate inputs. Furthermore, this study contributes to the literature by using country-specific techniques and aggregated and disaggregated manufacturing sectors as subjects for study. Meanwhile, previous studies use multi-country and multi-product approaches and focus on the aggregate sector. This study estimates the effects of TBT on the disaggregated sector, given its high share of imported inputs and reliance on export-oriented industries. TBT is constructed in a more detailed product level (HS-4 digit level) to provide more accurate results.

Influences of Landscape Configuration on River Water Quality

The present study investigated the effects of changes in landscape configuration on river water quality, which is calculated by chemical export coefficients, using spatial data onto 31 catchments in the southwestern part of the Caspian Sea basin by applying stepwise multivariate regression models. The water quality modeling has been carried out applying the chemical export coefficients of sulfate, bicarbonate, chlorine, calcium, magnesium, and sodium, and eight landscape metrics (including interspersion juxtaposition index, percentage of like adjacencies, aggregation index, clumpiness index, normalized landscape shape index, patch cohesion index, landscape division index, and splitting index), by which landscape configuration is analyzed. The results indicated that the sulfate (0.25 ± 0.33 gr ha−1yr−1), bicarbonate (0.61 ± 0.87 gr ha−1 yr−1), chlorine (0.17 ± 0.23 gr ha−1 yr−1), calcium (0.16 ± 0.21 gr ha−1 yr−1), magnesium (0.05 ± 0.07 gr ha−1 yr−1), and sodium (0.16 ± 0.21 gr ha−1 yr−1) are annually exported from the study catchments into the rivers. The change in landscape configuration has significantly explained the chemical export coefficients of sulfate, bicarbonate, chlorine, calcium, magnesium, and sodium. The findings showed the cohesion and coherence of the permanently irrigated land patches resulting in the discontinuity of the broad-leaved forest and grassland ecosystems degraded river water quality.

Editorial: Chemical Export to River Systems From the Critical Zone

Editorial: Chemical Export to River Systems From the Critical Zone

WTO Trade War Resolution for Japan's Chemical Export Restrictions to South Korea

The research analyses the trade war between South Korea and Japan from the perspective of international law. The trade war involving South Korea and Japan was triggered by a decision by the Supreme Court of South Korea which ordered several Japanese companies to pay compensation to victims of Japanese forced labor during World War II. As a result, on July 1, 2019, Japan imposed restrictions on chemical exports to South Korea. South Korea accused Japan of violating international trade regulations concerning export restrictions. Therefore, South Korea took action by boycotting goods from Japan. The two countries resolved to remove each other from the whitelist of countries that obtain preferential trade status via their activities. The research method used is normative legal research with a case approach. The result shows that the trade war involving Japan and South Korea worsened bilateral relations. The World Trade Organization (WTO) carried out several mechanisms related to solving the problem, namely through consultation and conciliation involving the two countries, but it still needs to resolve the issue. It was also planned to establish a panel between South Korea and Japan by the WTO, but it has not been implemented until now and beyond the timeframe set by the WTO in establishing the Panel. Therefore, the study proposes that South Korea and Japan can initiate arbitration as a solution for another effort to resolve the problem because the arbitration mechanism obtains binding and final decisions. DOI: https://doi.org/10.22304/pjih.v9n3.a6

Forecast of Chemical Export Trade Based on PSO‐BP Neural Network Model

With the gradual deepening of China’s reform and opening up, the degree of foreign development has been deepened, and its dependence on foreign trade has increased. The “export‐oriented” economic development has achieved results. Export trade is introducing advanced technology and equipment, expanding employment opportunities, and increasing government revenue. The export trade is affected by various domestic and international factors and is a complex nonlinear system. Although the traditional linear prediction method has the advantages of intuitiveness, simplicity, and strong interpretability, it is difficult to deal with the prediction problem of dynamic and complex nonlinear systems. The neural network is a nonlinear dynamic system, with strong nonlinear mapping ability, strong robustness, and fault tolerance. It has unique advanced advantages for solving nonlinear problems and is very suitable for solving nonlinear problems.

Variability of stream extents controlled by flow regime and network hydraulic scaling

AbstractStream networks expand and contract through time, impacting chemical export, aquatic habitat, and water quality. Although recent advances improve prediction of the extent of the wetted channel network (L) based on discharge at the catchment outlet (Q), controls on the temporal variability of L remain poorly understood and unquantified. Here we develop a quantitative, conceptual framework to explore how flow regime and stream network hydraulic scaling factors co‐determine the relative temporal variability in L (denoted here as the total wetted channel drainage density). Network hydraulic scaling determines how much L changes for a change in Q, while the flow regime describes how Q changes in time. We compiled datasets of co‐located dynamic stream extent mapping and discharge to analyze all globally available empirical data using the presented framework. We found that although variability in L is universally damped relative to variability in Q (i.e., streamflow is relatively more variable in time than network extent), the relationship is elastic, meaning that for a given increase in the variability in Q, headwater catchments will experience greater‐than‐proportional increases in the variability of L. Thus, under anticipated climatic shifts towards more volatile precipitation, relative variability in headwater stream network extents can be expected to increase even more than the relative variability of discharge itself. Comparison between network extents inferred from the L‐Q relationship and blue lines on USGS topographic maps shows widespread underestimation of the wetted channel network by the blue line network.

Combining Uranium, Boron, and Strontium Isotope Ratios (234U/238U, δ11B, 87Sr/86Sr) to Trace and Quantify Salinity Contributions to Rio Grande River in Southwestern United States

In semi-arid to arid regions, both anthropogenic sources (urban and agriculture) and deeper Critical Zone (groundwater with long flow paths and water residence times) may play an important role in controlling chemical exports to rivers. Here, we combined two anthropogenic isotope tracers: uranium isotope ratios (234U/238U) and boron isotope ratios (δ11B), with the 87Sr/86Sr ratios to identify and quantify multiple solute (salinity) sources in the Rio Grande river in southern New Mexico and western Texas. The Rio Grande river is a major source of freshwater for irrigation and municipal uses in southwestern United States. There has been a large disagreement about the dominant salinity sources to the Rio Grande and particularly significant sources are of anthropogenic (agriculture practices and shallow groundwater flows, groundwater pumping, and urban developments) and/or geological (natural groundwater upwelling) origins. Between 2014 and 2016, we collected monthly river samples at 15 locations along a 200-km stretch of the Rio Grande river from Elephant Butte Reservoir, New Mexico to El Paso, Texas, as well as water samples from agricultural canals and drains, urban effluents and drains, and groundwater wells. Our study shows that due to the presence of localized and multiple salinity inputs, total dissolved solids (TDS) and isotope ratios of U, B, and Sr in the Rio Grande river show high spatial and temporal variability. Several agricultural, urban, and geological sources of salinity in the Rio Grande watershed have characteristic and distinguishable U, Sr, and B isotope signatures. However, due to the common issue of overlapping signatures as identified by previous tracer studies (such as δ18O, δD, δ34S), no single isotope tracer of U, Sr, or B isotopes was powerful enough to distinguish multiple salinity sources. Here, combining the multiple U, Sr, and B isotope and elemental signatures, we applied a multi-tracer mass balance approach to quantify the relative contributions of water mass from the identified various salinity end members along the 200-km stretch of the Rio Grande during different river flow seasons. Our results show that during irrigation (high river flow) seasons, the Rio Grande had uniform chemical and isotopic compositions, similar to the Elephant Butte reservoir where water is stored and well-mixed, reflecting the dominant contribution from shallow Critical Zone in headwater regions in temperate southern Colorado and northern New Mexico. In non-irrigation (low flow) seasons when the river water is stored at Elephant Butte reservoir, the Rio Grande river at many downstream locations showed heterogeneous chemical and isotopic compositions, reflecting variable inputs from upwelling of groundwater (deeper CZ), displacement of shallow groundwater, agricultural return flows, and urban effluents. Our study highlights the needs of using multi-tracer approach to investigate multiple solutes and salinity sources in rivers with complex geology and human impacts.

Simulation of water and chemical transport of chloride from the forest ecosystem to the stream

The study evaluates the biogeochemical model ForSAFE-2D, designed to simulate water and chemical transport from the forest to the stream, by simulating the hydrology and the transport of the chemical tracer chloride (Cl−) along a forest hillslope in Northern Sweden. The simulated Cl− exports were in balance with the simulated inputs but measurements suggested a net release of Cl− from the catchment. Underestimated deposition inputs (deposition peaks and possibly dry deposition) were probably and partially responsible for this mismatch. However, we could not exclude that other soil biogeochemical processes omitted in ForSAFE-2D could also contribute to Cl− exports from the catchment. The study showed that ForSAFE-2D is a promising tool to better understand the factors that regulate the chemical export from the forest to the stream. The results also confirmed that there are limitations in using Cl− as a tracer in forest ecosystems.

Analysis on Export Competitiveness of Chinese Chemical Products

First of all, this paper summarizes the research progress of international Chemicals which are a kind of products that cannot be ignored in people’s life and production. Under the call of national policy of fine chemical and green chemical industry, in recent years, China’s chemical products output ranks the top in the world, and the export trade grows rapidly, but the export of domestic chemical products keeps a deficit in foreign trade. In the face of complex and changeable international competition and foreign trade situation, it is helpful for the sustainable and healthy development and progress of domestic economy to comprehensively analyze and elaborate the structure, competitiveness and related influencing factors of China’s chemical export. This paper analyzes the research and development of international competitiveness and constructs the research framework and main research methods of this paper. Based on the research results of international competitiveness at home and abroad, the evaluation system of export competitiveness of Chinese chemicals is constructed. Secondly, this paper analyzes the export status of domestic chemicals and related manufactured products from the main body of chemical exports, chemical exports and chemical export regions. This paper analyzes the international competitiveness level of chemical products in China by using the international market share, dominant comparative advantage index and trade competitiveness index. The results show that at present, China’s chemical products are still very lack of international competitiveness. In order to further analyze the factors that affect the competitiveness of chemical manufacturing industry, based on Porter diamond model and previous research results, this paper establishes a multiple regression model, and analyzes the impact of four indicators of capital, scientific research and innovation level, industrial concentration and scale economy on the international competitiveness of chemical manufacturing industry. Finally, based on the results of empirical analysis, this paper puts forward suggestions to improve the export competitiveness of domestic chemicals and related manufactured goods.

US-China trade war: Impact on chemical exporting firms from India to US

With the onset of the US-China trade war in July 2018, the trade patterns between China, the US, and India have undergone a tremendous change. The number of products in which China had a competitive advantage in terms of exports to the US has declined in the last 9 months. A number of developing countries may be benefitted from the ongoing tariff war between the US and China, like Vietnam, Brazil, India, and Korea. In the present study, an attempt has been made to analyse the impact of the US-China trade war on exports of India to the US. The sector which has been selected is the chemical sector comprising of organic and inorganic chemicals as chemicals are one of the top-exported products from India to the US. To analyse the impact, the difference-in-differences technique of regression has been applied. The results indicate that after July 2018, i.e., the commencement of the US-China trade war, the impact on firms exporting chemicals from India to the US has been significant and firms in India may be a potential source for chemicals for the US provided the right policy measures are exercised in India. The results indicate that the trade war between the US and China has had a positive impact on the chemical exports from India to the US. The chemical exports from India to the US have increased post-July 2018, though not at a steep rate. This indicates that India has the potential to export chemicals to the US

Analysis of cobalt flows in mainland China: Exploring the potential opportunities for improving resource efficiency and supply security

Cobalt is an increasingly important strategic metal with the emerging of clean energy technologies. China is a resource scarcity country but the world’s largest cobalt consumer. It is of great strategic significance to study the application and current status of cobalt resources for the sustainable development of China’s economy. The objective of this study is to quantitatively investigate the status of cobalt flows from raw materials to waste management in mainland China in 2015 by using material flows analysis (MFA), and to identify the material efficiency and supply security strategy for sustainable use of cobalt. The results show that China’s overall supply of raw materials, chemical production and product manufacture of cobalt in 2015 were 66.5 kt, 62.9 kt and 45.4 kt, respectively. China’s cobalt is highly reliant on imports with a dependency of over 80%. Cobalt outflows were mainly from exports of cobalt chemicals and end-use products. At the end-use product stage, batteries consume the most cobalt, followed by superalloys, cemented carbides and magnets. The emerging of the electric vehicle industry seems to increase the burden of cobalt supply, but also represents huge opportunities for cobalt recycling as a secondary resource. Future efforts on improving material efficiency and ensuring supply security should focus on reducing losses at the beneficiation process by technology upgrades, improving the cobalt recycling rate by integrating cobalt resources into China’s circular economy and environment policy, and establishing national cobalt collection system. This study can provide guidance for future decision-making around the clean production and rational utilization of cobalt resources.

Impact of tighter controls on Japanese chemical exports to Korea

The Japanese Ministry of Economy, Trade and Industry announced recently that they will terminate preferential treatment in the licensing of specific chemical products for export to South Korea. This announcement evoked concern that the impact on Korean semiconductor and electronics industries, which rely heavily on imports from Japan, might cause a serious supply shortage in the global semiconductor market. To assess the economic impact of tighter export controls, this study simulates: (a) imposition of an export tax on chemical products; and (b) a productivity decline in the electronics sector in Korea, using a world trade computable general equilibrium model. The results of these simulations indicate that such a productivity decline would cause only slight harm to the Japanese and world economies, aside from the electronics sector in Korea, and that an export tax would significantly distort trade patterns and undermine the welfare of Japan and Korea in a similar magnitude. However, welfare loss normalized for economy size would be far smaller in Japan than in Korea.

Da li je struktura izvoza uticala na ekonomski rast zemalja Evropske Unije u Centralnoj i Istočnoj Evropi?

This study analyzes export composition effects on economic growth in the European Union (EU) countries of Central and Eastern Europe (CEE) during 1999-2016. The results confirm that the fuel and food exports have boosted growth after EU accession. As expected, agricultural exports have no effect on growth. Due to the different comparative advantages, the CEE countries have still relied on some raw material exports while developing manufactured exports. The results also indicate that the transportation equipment, textile, steel, and chemical exports have accelerated growth. This can be attributed to the economies of scale in production, given their greater access to EU markets.