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In the booming electric vehicle market, the demand for refined cobalt is showing a blowout growth. China is the largest cobalt-refiner and cobalt-importer in the world. However, the life cycle inventory and potential environmental impact from cobalt refining in China have not been clearly illustrated. This paper builds a comprehensive inventory to support the data needs of downstream users of cobalt sulfate. A “cradle-to-gate” life cycle assessment was conducted to provide theoretical support to stakeholders. A life cycle assessment was performed based on ISO 14040 to evaluate the potential environmental impact and recognize the key processes. The system boundary of this study contains four stages of cobalt sulfate production: mining, beneficiation, primary extraction, and refining. Except for the experimental data used in the primary extraction stage, all relevant data are actual operating data. The normalization value was calculated based on the latest released global emission and extraction data. Normalization results show that the potential impacts of cobalt refining were mainly concentrated in the fossil depletion and freshwater ecotoxicity categories. The beneficiation stage and the refining stage account for 72% and 26% of the total normalization value, respectively. The beneficiation stage needs to consume a lot of chemicals and energy to increase the cobalt content, due to the low grade of cobalt ore in China. Compared with cobalt concentrate, the use of cobalt-containing waste (e.g., cobalt waste from EV batteries) can ease endpoint impact by up to 73%. With the application of the target electricity structure in 2050, the potential impact of China’s cobalt sulfate production on global warming, fossil depletion, and particulates formation can be reduced by 24%, 22%, and 26%, respectively. Findings indicate that the chemical inputs and electricity consumption are primary sources of potential environmental impact in China’s cobalt sulfate production. Promoting the development of urban mines can reduce excessive consumption of chemicals and energy in the beneficiation stage. The environmental benefits of transforming the electricity structure and using more renewable energy to reduce dependence on coal-based power in the cobalt refining industry were revealed.

Galvanized sheet is the most widely used coated steel plate globally in the industry of construction, automobile, electronics manufacturing, etc. Large amounts of resources and energy are used in galvanized sheet production, which likewise generates vast amounts of pollutant emissions. In the face of the rapid growth of the production and demand of galvanized sheet in China, it is very important to find out the key factors of the environment impact in the production of galvanized sheet. An evaluation of the environmental impact of galvanized sheet production in China was conducted by using the framework of life cycle assessment to improve resource saving and environmental protection in the galvanized sheet industry, and update the life cycle inventory database of galvanized sheet production. The environmental impact assessment was carried out based on the life cycle assessment framework by the use of ReCiPe 2016 method which was applicable on a global scale to evaluate the environmental impact of galvanized sheet production. Methods of uncertainty analysis and sensitivity analysis were adopted to provide credible support. The midpoint categories of global warming and fossil resource scarcity, as well as the endpoint categories of human health contributed most to environmental burden, which were mainly caused by carbon dioxide emissions and coal consumption. Environmental impact was dominated by the key process of continuous casting billet production, followed by electrolytic zinc production and electricity generation. Additional CO2-reducing measures should be implemented in galvanized sheet production to slow the effect of global warming. Moreover, biomass char reducing agents, rather than coal-based reducing agents, should be utilized in steelmaking to reduce fossil resource consumption. Furthermore, renewable energy, rather than coal-based electricity, should be used in galvanized sheet production to reduce carbon emissions and fossil resource consumption. Increasing the recycling rate of scrap steel and zinc waste can save resources and reduce environmental burden. The results of this study can provide guidance in the reduction of resource consumption and environmental burden of galvanized sheet production to the maximum extent.

Water consumption and pollution in wheat production, which are worth paying attention in agricultural countries and arid regions, need to be assessed systematically and comprehensively. China, one of the largest wheat-producing country in the world, should be concerned about this issue. Thus, an impact-oriented water footprint assessment of wheat production in China was conducted based on the ISO 14046 standard to quantify water-related environmental impacts. We quantified the environmental impacts on human health and ecosystem quality categories of wheat production from 2009 to 2016 and evaluated the spatial variation of these categories in 2016. Results showed that the environmental impacts on human health and ecosystem quality categories in 2016 were 5.15 × 10−4 DALY/t and 37.17 PDF·m2·yr/t, respectively. Key factor analysis showed that the overall environmental impacts were primarily derived from fertilizer production, diesel production, and direct water consumption and emission. The dynamic analysis results revealed that the temporal variations in impacts were associated with water and fertilizer consumption. Areas with high potential impacts were mainly congregated in the North China Plain and Xinjiang Province due to their high wheat yields. Ecosystem quality was negatively correlated with wheat yield, and human health was positively correlated with crop water requirement. Therefore, on the basis of ensuring grain production, improving the utilization efficiency of irrigation water and reducing fertilizer and diesel consumption are the priorities for the management of agricultural water resources.

Straw pulp in China, which is the world's largest producer of this material, suffers from water and energy shortages during its entire life cycle. However, limited systematic studies have focused on these issues, and decision makers need be provided with improvement methods for the environmental performance. Thus, an impact-oriented energy and carbon coupled water footprint analysis was conducted in this study based on ISO standards. Results showed that the impact of energy consumption and carbon emissions exceeded that of water footprint. Carcinogens, non-carcinogens, and freshwater ecotoxicity also played effective roles in improving the environmental performance. Optimizing key indirect processes, including chemicals production, steam preparation, electricity generation, wood pulping, and fertilizer recovery, dominated the reduction in environmental burdens. Direct freshwater consumption and wastewater disposal played additional effective roles in controlling water footprint. The water network was thus optimized by a water pinch analysis to decrease the freshwater consumption and pollutant emissions by maximum values of 91.5% and 99.7% after optimization, respectively. Meanwhile, carbon dioxide, methane, chromium, arsenic, mercury, titanium, copper, strontium, total nitrogen, total phosphorus, BOD5, and COD were the main pollutants. Overall, the environmental impact can be further reduced by diminishing coal power ratio in national energy structure, adopting recovered steam, and considering multistage regeneration water network to cope with different water use demands.

Global water resources are under tremendous pressure influenced by population growth and economic development. Considering that the agricultural sector accounts for the largest consumption and that China is one of the major agricultural countries, this study conducted an impact-oriented water footprint analysis to quantify the environmental burdens of crop production in China from a life cycle perspective. The temporal variation of potential environmental impacts during 2008–2017 was evaluated, and 334 cities in China were used to investigate the spatial characteristics of environmental burdens. Results showed that the environmental burdens were mainly ascribed to direct consumption, fertilizer production, and diesel production. The overall burdens uninterruptedly increased from 2008 to 2015 and then declined in 2016. The decomposition results of temporal variation demonstrated that agricultural economic scale and crop productivity were the largest positive and negative contributors to burden growth, respectively. The burdens exhibited an evident spatial autocorrelation, and high–high agglomerations were mostly located in the North China Plain and Yangtze River Delta due to the superior natural resource endowments and dense population in these regions. Such factors as natural resource endowments (i.e., cultivated land and precipitation), agricultural input intensity (i.e., fertilizer and diesel), and effective irrigation area proportion significantly influenced the spatial variation of environmental impacts at the city level. Therefore, adopting water-saving technologies, strengthening fertilization management, promoting large-scale and mechanized agriculture, and choosing clean alternative fuels are highly recommended to achieve sustainable agricultural development. Furthermore, in consideration of the dominance of high–high clusters in crop production in China, advanced and eco-friendly production technologies should be vigorously incentivized in these regions to enhance their agglomeration and radiation force.

Available water resource scarcity is a severe problem in China. Cotton production is coupled with substantial irrigation requirements and nutrient loss. Systematic analysis of water consumption and pollutant emissions in direct and indirect processes is a prerequisite to enhance the environmental performance of cotton production. This study conducts a life cycle assessment-based water footprint analysis of China's cotton production to identify the links among water consumption, pollutant emissions and migration, driving factors, and spatiotemporal variation. Spatiotemporal, statistical coupling, and multi-factors correlation analyses are utilized to explore interannual variability, identify optimization areas, realize optimization potential, and provide data support for sustainable development. Results show that the potential impact of producing 1 t cotton on the ecosystem quality and human health was 152.83 species·yr and 1.69 × 10−3 disability-adjusted life years, respectively. The direct environmental impact caused by water consumption and nutrient loss, and the indirect impact attributed to fertilizer and diesel production restricted the sustainable development of cotton production in China. The environmental impact of cotton production in China displays an apparent regional concentration. Xinjiang Province is the crucial region for addressing the challenge of water sustainability in cotton production. Qinghai and Inner Mongolia provinces were recommended to develop cotton cultivation to ease the regional concentration situation and improve the national sustainability of cotton production. Several practical measures, including straw returning, energy substitution, and drip irrigation under the degradable film, are recommended to improve environmental performance of cotton production.

The irrational grain virtual water flow caused by spatial mismatch in water and available arable land threatens grain security in China. However, systematic and quantitative assessment of grain virtual water flow on environmental impacts has rarely been conducted. This study analyzes the flow patterns of China's interprovincial and international grain virtual water and resulting environmental impacts during 2019–2020, with a focus on water-saving and environmental benefits. Results showed that the main importers and exporters of environmental impact flow were inconsistent with those of virtual water flow, and maize trade was the main contributor to these flows. China's grain virtual water flow resulted in approximately 2.21 Gm3 water loss and increased the impacts on water scarcity and human health by 1.61 Gm3deprived and 3.42 × 104 DALY, respectively. Nevertheless, the grain virtual water flow generated benefits in ecosystem quality by 1.20 × 10−3 species. yr, compared with the no-grain transfer scenario. Exporting maize from Shanxi, Inner Mongolia, Gansu, and Xinjiang provinces dominated water loss and environmental burdens, whereas exporting rice from Hubei, Hunan, Anhui, and Jiangxi provinces contributed mostly to water-saving and environmental benefits. Importing grains from abroad also contributed to water-saving and ecosystem quality impact reduction. Measures, including improving irrigation water productivity and developing a regional compensation mechanism for dominant maize exporters, strengthening green water management in dominant rice-exporting areas, achieving the diversified development of China's trade partners, and implementing strict tariff quota administration, are suggested to alleviate environmental impacts and ensure grain security.

With the increasing consumer demand and only 31% of the self-sufficiency rate, how to mitigate the supply safety of edible vegetable oil in an environmentally sustainable manner is a tremendous challenge for China. This study comprehensively qualified the potential environmental impact from the major edible vegetable oil production (i.e., soybean oil, rapeseed oil, and peanut oil) in China through the life cycle assessment method. Results show that rapeseed oil and peanut oil are environmentally friendly. More than 20% of environmental contamination could be avoided in 2025 by replacing the further increase in soybean oil production with a mix of the other products. The key contribution analysis indicates that the agricultural phase is a significant source of environmental pollution due to excessive fertilizer production and irrigation water consumption. During the oil processing phases of soybean oil and peanut oil, steam production also contributed to considerable environmental impact. Therefore, applying new fertilizers, developing water-saving irrigation technologies, and optimizing the steam heat exchange net are suggested. Moreover, increasing the oil extraction rate through electrotechnical technology has great potential in reducing the environmental damage caused by oil-bearing crop planting. Based on the spatial discrepancy in the agricultural phase, advantageous planting regions (e.g., Anhui, Henan, Shandong, and Jiangsu) are references for the further planting structure adjustment. Meanwhile, advocating scientific diets and optimizing the industry layout are recommended to ensure the healthy and sustainable development of China's edible vegetable oil industry.

Ambient air pollution is a global issue, which poses serious threat to humans and ecosystem. To address such a threat, air pollution damage needs be explored from the environmental and economic perspectives to achieve precise management aimed at the region and industry. Here, we analyze carbon dioxide, sulfur dioxide, particulate matters, and nitrogen oxides related damage at the city and national levels. During 1990–2019 in China, the rapid increase in the ecosystem quality damage mainly resulted from 2.6 times growth of carbon dioxide, whereas particulate matter caused a slight decrease in human health. Economic costs peaked at US$8.08 × 1011 in 2014 and fell back to US$5.14 × 1011 in 2019. Air pollution-related damage mainly occurs in urban agglomeration areas that consume substantial fossil fuel for power generation, metals smelting, and residential and vehicular use. Results suggest focusing on the aforementioned high-polluting sectors, promoting renewable energy instead of coal, and considering the differences in pollution sources of cities to achieve air pollution damage reduction by targeted policies and measures.

Nowadays, agricultural production places an enormous burden on freshwater resources, and the environmental external cost caused by the restoration of water quality degradation has attracted great attention. Maize is regarded as one of the world's major food security crops, and China is the second-largest maize producer. Thus, this study conducts an impact-oriented water footprint coupled economic impact assessment to quantify the water-related environmental impacts and economic burden caused by China's maize production from 2008 to 2017. Results show that the overall damage to human health and ecosystem quality of China's maize production in 2017 were 4.32 × 104 DALY and 4.62 × 103 Species·yr, respectively. The total economic cost was $ 2.15 × 1011, which included an internal cost of $ 5.99 × 1010 and external cost of $ 1.55 × 1011. Key factor analysis demonstrates that diesel and fertilizer production dominated the reduction in ecological and external cost burdens. Direct water consumption and labor cost played leading roles in human health and internal cost, respectively. The spatiotemporal variation assessment indicates that Inner Mongolia and Heilongjiang were the hotspots for water footprint and economic impact assessment results after considering the yield factor. The national average water footprint and economic impact caused by producing 1 ton of maize showed an upward trend from 2008 to 2015, however, a significant decline transpired later. Overall, improving the resource efficiency (i.e., diesel and freshwater), scientific application of fertilizer and reducing labor input can further lessen the water footprint and economic impact of maize production. Developing the social environment can also generate indirect environmental and economic benefits to China's maize production.

Electrolytic manganese metal is widely used in various industrial fields, especially in the steel industry because of its characteristics. However, Electrolytic manganese metal production is one of the industries with high resource and energy consumption and substantial waste discharge. The study quantified the environmental performance of electrolytic manganese metal production by conducting a life cycle assessment using the ReCiPe2016 method. Uncertainty analysis via Monte-Carlo simulation was also implemented. Environmental burden was mainly ascribed to manganese resource-related production processes and electricity generation. Although production in China has progressed compared with the previous years, a gap remains compared with South Africa’s use of selenium-free technology. Analysis of coal-based electricity generation replaced by other renewable energy sources showed considerable environmental benefits. This study aims to provide information for the improvement of electrolytic manganese metal production. The reduction of the environmental burdens of electrolytic manganese metal production can be achieved by utilizing an advanced production technology to control the amount of raw materials and improve resource efficiency, recycling resources in waste, and converting coal-based electricity into other renewable alternatives (e.g., hydropower, wind, and solar energy).