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Carbon emission reduction in China matters to global climate change mitigation. China has been experiencing extensive land changes, which profoundly influence terrestrial ecosystem carbon storage (TECS) and carbon emissions. Scholars have predicted influences of land changes on TECS in China with scenarios obtained from global integrated assessment models (IAMs), which lack national details. Moreover, universally existing variations in land-use intensity have not been considered when estimating influences on TECS. This study simulated changes of land-use intensity of China from 2000 to 2050 using CLUMondo under China-specified policies for sustainable development modeled by a national IAM named Threshold21-China. We proposed a more precise TECS estimation method by distinguishing land-vegetation and land-soil types. Results demonstrated that under scenario with preceding policies, the total TECS can increase by 865.5 Tg C from 2000 to 2050. Through implementing preceding policies, TECS loss by conversions from cultivated land to artificial surfaces can decline by 82 Tg C, and new TECS accumulated by increased and densified forests can increase by 73 Tg C. Mountainous and rapidly urbanizing regions are sensitively influenced and need more restrict land change management policies. This study demonstrates the significance of sustainable development policies for TECS conservation and indicates specific critical regions. • Introducing national IAM into land change simulation. • Considering land-use intensities in land change simulation. • Proposing an improved TECS estimation method. • Estimating influences of land changes on China's TECS. • TECS accumulation could be improved under sustainable policies. [ABSTRACT FROM AUTHOR]

• We assessed the climate change impact on wheat production in China. • We employed the FGLS, DOLS, and D–K estimation techniques. • Temperature negatively affected wheat production in the long–run. • Precipitation contributed positively to wheat production in the long-run. • Agro–chemical input (fertilizer use) enhanced wheat production in the long–run. Northern and Southern regions are the two major wheat production belts of China. Agro–climatic resources have changed significantly in recent years, threatening staple food production in these regions. As a result, it is critical to investigate the long–term effect of climate change and agri–inputs on wheat production in China's top six wheat producing provinces (Hebei, Shandong, Henan, Jiangsu, Anhui, and Hubei) from 1995 to 2020. The estimated long-run results from the FGLS, DOLS, and D–K estimators revealed that climatic factors, specifically temperature, had a negative impact on wheat production, while precipitation had a positive impact. The findings also revealed that agrochemical inputs, such as fertilizer, increases wheat production, whereas pesticide use decreases wheat production significantly. The results from the Dumitrescu–Hurlin panel causality test showed a bidirectional causality between rainfall, fertilizer use, and cultivated area with wheat production, while a unidirectional causality association is running from labor force to wheat production. The current study provides several critical policy recommendations for China's sustainable food production through green agricultural practices and robust climate mitigation strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Dietary change presents an opportunity to meet the dual challenges of non-communicable diseases and the effects of climate change in China. Based on a food survey and reviewed data sets, we linked nutrient composition and carbon footprint data by aggregating 1950 types of foods into 28 groups. Nine dietary scenarios for both men and women were modeled based on the current diet and latest National Program for Food and Nutrition. Linear uncertainty optimization was used to produce diets meeting the Chinese Dietary Reference Intakes for adults aged 18–50 years while minimizing carbon footprints. The theoretical optimal diet reduced daily footprints by 46%, but this diet was unrealistic due to limited food diversity. Constrained by acceptability, the optimal diet reduced the daily carbon footprints by 7–28%, from 3495 to 2517–3252 g CO 2 e, for men and by 5–26%, from 3075 to 2280–2917 g CO 2 e, for women. Dietary changes for adults are capable of benefiting China in terms of the considerable footprint reduction of 53–222 Mt. CO 2 e year − 1 , when magnified based on the Chinese population, which is the largest worldwide. Seven of eight scenarios showed that reductions in meat consumption resulted in greater reductions in greenhouse gas emissions. However, dramatic reductions in meat consumption may produce smaller reductions in emissions, as the consumption of other ingredients increases to compensate for the nutrients in meat. A trade-off between poultry and other meats (beef, pork, and lamb) is usually observed, and rice, which is a popular food in China, was the largest contributor to carbon footprint reductions. Our findings suggest that changing diets for climate change mitigation and human health is possible in China, though the per capital mitigation potential is slight lower than that in developed economies of France, Spain, Sweden, and New Zealand. [ABSTRACT FROM AUTHOR]

The carbon balance in urban areas has become a major research challenge and a principal policy concern in efforts to address anthropogenic climate change. Rapid urbanization and industrialization in China urge the search for integrated strategies to mitigate and adapt to climate change, which not only limit to traditional infrastructure sectors, but also cover urban green infrastructure, because plants and soils function as carbon sinks through biotic sequestration. This study presents a nationwide study about how urban green infrastructure could contribute to the carbon balance in 35 major Chinese cities. By the end of 2010, the total area of urban green spaces (the dominant components of urban green infrastructure) accounts for 6.38% of the total land area of these cities and represented 51.7% of the total urban green spaces of all 657 cities in China. Based on empirical data from the literature, the total amount of carbon stored in the vegetation of the urban green infrastructure of 35 cities was estimated at 18.7 million tons, with an average carbon density of 21.34 t/ha. In 2010, the amount of carbon sequestration totaled 1.90 million tons with an average carbon sequestration rate of 2.16 t/ha/year. Collectively, only 0.33% of the carbon emissions from fossil fuel combustion can be offset, ranging from 0.01% in Hohhot to 22.45% in Haikou. Nevertheless, the dominance of young vegetation stands in Chinese urban green infrastructure suggests this small carbon sequestration efficiency could become substantial in the near future, given that appropriate policies and management practices are adopted to promote urban green infrastructure for climate change mitigation and adaptation. [ABSTRACT FROM AUTHOR]

As bioenergy produces neutral or even negative carbon emissions, the assessment of biomass resources and associated emissions mitigation is a key step toward a low carbon future. However, relevant comprehensive estimates lack in China. Here, we measure the energy potential of China's domestic biomass resources (including crop residues, forest residues, animal manure, municipal solid waste and sewage sludge) from 2000 to 2016 and draw the spatial-temporal variation trajectories at provincial resolution. Scenario analysis and life cycle assessment are also applied to discuss the greenhouse gas mitigation potentials. Results show that the collectable potential of domestic biomass resources increased from 18.31 EJ in 2000 to 22.67 EJ in 2016 with overall uncertainties fluctuating between (−26.6%, 39.7%) and (−27.6%, 39.5%). Taking energy crops into account, the total potential in 2016 (32.69 EJ) was equivalent to 27.6% of China's energy consumption. If this potential can be realized in a planned way to displace fossil fuels during the period 2020–2050, cumulative greenhouse gas emissions mitigation would be in the range of 1652.73–5859.56 Mt CO 2 -equivalent, in which the negative greenhouse gas emissions due to the introduction of bioenergy with carbon capture and storage would account for 923.78–1344.13 Mt CO 2 -equivalent. Contrary to increasing bioenergy potentials in most provinces, there are declining trends in Tibet, Beijing, Shanghai and Zhejiang. In addition, Yunnan, Sichuan and Inner Mongolia would have the highest associated greenhouse gas mitigation potentials. This study can provide valuable guidance on the exploitation of China's untapped biomass resources for the mitigation of global climate change. • China's bioenergy potential in 2016 accounted for 27.6% of its energy consumption. • The bioenergy potential in Tibet, Beijing, Shanghai and Zhejiang was declining. • GHG mitigation potentials of China's bioenergy would be 1653–5860 Mt CO 2 e by 2050. • China's bioenergy can contribute 6–21% to a global carbon mitigation goal in 2050. [ABSTRACT FROM AUTHOR]