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Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000-2012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = ±7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000-2013 may be larger than China's estimated total forest sink in 1990-2007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000-2009 (2.6 gigatonnes of carbon).
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Carbono/análisis , Materiales de Construcción/provisión & distribución , Combustibles Fósiles/estadística & datos numéricos , Dióxido de Carbono/análisis , Secuestro de Carbono , China , Cambio Climático , Carbón Mineral/estadística & datos numéricos , Árboles/metabolismo , IncertidumbreRESUMEN
The energy oriented mine ecological restoration mode of photovoltaic+ecological restoration provides a breakthrough for alleviating the dilemma of photovoltaic land development and solving the urgent need for restoration of abandoned mining land. Taking a mining area in central Liaoning Province as an example, we established three photovoltaic+mining ecological restoration modes, including forest-photovoltaic complementary, agriculture-photovoltaic, and grass photovoltaic complementation. Combined with the life cycle assessment method, we calculated and assessed the potential of photovoltaic+mining ecological restoration in carbon reduction and sink enhancement. The average annual carbon reduction and sink increase was 514.93 t CO2·hm-2 under the photovoltaic+mining ecological restoration mode, while the average annual carbon reduction per megawatt photovoltaic power station was 1242.94 t CO2. The adoption of photovoltaic+ecological restoration mode in this mining area could make carbon reduction and sink enhancement 6.30-7.79 Mt CO2 during 25 years. The carbon reduction and sink increment mainly stemmed from the photovoltaic clean power generation induced carbon reduction, accounting for 96.4%-99.4%, while the contribution of ecosystem carbon sink increment was small, accounting for only 0.6%-3.7% of the total. Among different photovoltaic+ecological restoration modes, the carbon reduction and sink increment was the largest in forest-photovoltaic complementary (7.11 Mt CO2), followed by agriculture-photovoltaic (7.04 Mt CO2), and the least in grass photovoltaic complementation (6.98 Mt CO2). Constructing the development mode of "photovoltaic+mining ecological restoration" could effectively leverage the dual benefits of reducing emissions from photovoltaic power generation and increase sinks from mining ecological restoration, which would be helpful for achieving the goal of carbon neutrality in China.
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Secuestro de Carbono , Ecosistema , Minería , China , Restauración y Remediación Ambiental/métodos , Modelos Teóricos , Carbono/química , Carbono/análisis , Conservación de los Recursos Naturales/métodos , Dióxido de Carbono/análisis , Energía SolarRESUMEN
Liaoning is a province with large energy consumption and carbon emissions. Management of carbon emissions in Liaoning Province is crucial to realizing China's carbon peaking and carbon neutrality goals. To clarify the driving factors and trends of carbon emissions in Liaoning Province, we analyzed the impacts of six factors on carbon emissions in Liaoning Province through STIRPAT model based on carbon emission data from 1999 to 2019. The impact factors included population, urbanization rate, per-capita GDP, secondary industry ratio, energy consumption per unit GDP, and coal consumption ratio. Nine forecasting scenarios with three economic and population growth models and three emission reduction models were set up, and their carbon emission trends under the above nine forecasting scenarios were predicted. The results showed that the main driving factor of carbon emissions in Liaoning Province was per-capita GDP, and that the main inhibitor was energy consumption per unit GDP. The carbon peak year in Liaoning Province would fluctuate between 2020 and 2055 under the nine forecasting scenarios, with peak values ranging from 544 to 1088 million tons CO2. The medium economic development growth and high carbon emission reduction scenario would be the optimal carbon emission scenario in Liaoning Province. Under this forecasting scenario, Liaoning Province could achieve carbon peak (611 million tons CO2) by 2030 without affec-ting economic development through optimizing energy structure and controlling the intensity of energy consumption. Our results would be helpful for seeking the best path for carbon emission reduction in Liaoning Province and providing a reference for its realization of carbon peaking and carbon neutrality goals.
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Dióxido de Carbono , Carbono , Carbono/análisis , Dióxido de Carbono/análisis , Desarrollo Económico , China , PredicciónRESUMEN
To reduce greenhouse gas (GHG) emissions, biomass has been increasingly developed as a renewable and clean alternative to fossil fuels because of its carbon-neutral characteristics. China has been investigating the rational development and use of bioenergy for developing its clean energy and achieving carbon neutrality. Substituting fossil fuels with multi-source and multi-approach utilized bioenergy and corresponding carbon reduction in China remain largely unexplored. Here, a comprehensive bioenergy accounting model with a multi-dimensional analysis was developed by combining spatial, life cycle, and multi-path analyses. Accordingly, the bioenergy production potential and GHG emission reduction for each distinct type of biomass feedstock through different conversion pathways were estimated. The sum of all available organic waste (21.55 EJ yr-1) and energy plants on marginal land (11.77 EJ yr-1) in China produced 23.30 EJ of bioenergy and reduced 2,535.32 Mt CO2-eq emissions, accounting for 19.48% and 25.61% of China's total energy production and carbon emissions in 2020, respectively. When focusing on the carbon emission mitigation potential of substituting bioenergy for conventional counterparts, bioelectricity was the most effective, and its potential was 4.45 and 8.58 times higher than that of gaseous and liquid fuel alternatives, respectively. In this study, life cycle emission reductions were maximized by a mix of bioenergy end uses based on biomass properties, with an optimal 78.56% bioenergy allocation from biodiesel, densified solid biofuel, biohydrogen, and biochar. The main regional bioenergy GHG mitigation focused on the Jiangsu, Sichuan, Guangxi, Henan, and Guangdong provinces, contributing to 31.32% of the total GHG mitigation potential. This study provides valuable guidance on exploiting untapped biomass resources in China to secure carbon neutrality by 2060.
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Carbon capture and storage (CCS) technology is an important way to slow down the continuous increase in atmospheric CO2 concentration and to achieve the dual carbon target. Carbon capture and storage through biomass ash is a secure, permanent, and environment friendly way. To better understand the characteristics of biomass ash carbon capture and storage, we summarized progresses on biomass ash carbon capture and storage, clarified the mechanisms of biomass ash carbon sequestration, analyzed the influencing factors, and explored its applications in various domains. The capacity of CCS by biomass ash mainly derived from alkaline earth metal oxides of CaO and MgO. The actual carbon sequestration efficiency is affected by factors such as biomass source, chemical composition, temperature, humidity, pressure, and CO2 concentration. However, the underlying mechanism is unclear. The CCS capacity of biomass ash significantly impacts its potential applications in building materials reuse, soil quality improvement, and adsorbents carbon capture and storage absorbent preparation. Long-term research is critically needed. For future studies, we should strengthen the research on the carbonization efficiency of biomass ash from multiple sources, establish a database related to the impact of biomass ash carbonization, build a methodological system to promote scientific management of biomass ash, develop biomass ash carbon capture and storage technologies, and quantitatively assess its role in carbon sequestration.
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Dióxido de Carbono , Carbono , Dióxido de Carbono/química , Biomasa , Óxidos , Temperatura , Secuestro de CarbonoRESUMEN
Exploring the spatio-temporal variation characteristics of carbon source and carbon sink under different disposal methods of crop straw is of great significance for optimizing the utilization policy of crop straw resources in China and realizing the goal of maximizing carbon emission reduction and carbon neutralization. Based on data from National Statistical Yearbook, we examined the changing trends of both the amount and value of carbon emission, carbon emission reduction, carbon sink enhancement under different crop straw disposal methods in 31 provinces of Chinese mainland. The results showed that the mean annual carbon emissions of straw burning in China from 2008 to 2019 were 8.74 million tons of CO2e. Since 2014, the mean annual reduction rate of carbon emissions was 17.3%. The mean annual carbon emission reduction of energy utilization was 39.82 million tons of CO2e, with solid briquette fuel produced by straw contributing the most with a contribution of about 98%. The amount of carbon sequestration of straw returning to field was increasing annually, with an average annual value of 271 million tons of CO2e. There was a carbon ecological surplus in straw disposal in China. The annual growth rate of net carbon emission reduction was 9.8%. The net carbon emission reduction intensity and its value were increasing, reaching 2.62 t·hm-2 and 76.19 yuan·hm-2 in 2019, respectively. A spatial pattern of 'high in the east and low in the west' was observed for the mean annual carbon emissions of straw, energy carbon emission reduction, carbon sink of straw returning to the field, and net carbon emission reduction in China, with main external characteristics of the regional differences and spatial aggregation.
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Agricultura , Carbono , Agricultura/métodos , Carbono/análisis , Secuestro de Carbono , China , SueloRESUMEN
Ecosystem services are the bridge between ecosystem functions and human welfare. Climate regulation service (CRS) has an extremely important role in ecosystem services. It is important to conduct a comprehensive assessment based on the whole process of CRS occurrence for scientific assessment of ecosystem services. With Fuzhou City as a case, we carried out the assessment of CRS at the local and municipal scales, and analyzed the spatial and temporal variations of CRS at the administrative unit and land use and land cover scales. The results showed that the aggregated physical capacity of CRS in Fuzhou City was 4.01×1012 MJ (monetary value 613.944 billion yuan, GDP 561.808 billion yuan) and 4.66×1012 MJ (monetary value 714.002 billion yuan, GDP 785.681 billion yuan) in 2015 and 2018, respectively, and that the monetary value of CRS was roughly equivalent to the GDP of that year. The main land use/cover (LULC) type was woodland, cultivated land, and water area, which accounted for 57%, 15%, and 9% of Fuzhou's land area, respectively. Water area contributed the most to Fuzhou's CRS, with a contribution of over 60% in 2018, higher than woodland (12%), and cultivated land (13%). The CRS was lower in built-up areas and eastern farming areas. Between 2015 and 2018, the area of LULC change in Fuzhou was 1805.5 km2. The largest changes were cultivated land and wood land. The main land use transfer direction was between cultivated land and woodland, woodland and garden land, cultivated land and residential and industrial and mining land. The aggregated physical capacity of CRS changed by 6.74×1011 MJ, while the corresponding monetary value of 103.58 billion yuan. The CRS changes were concentrated in the central and western regions such as Minhou, Minqing, and Yongtai, and the western mountainous regions such as Luoyuan and Fuqing. The most drastic change of CRS was found in water area. The conversion of water areas produced extremely strong changes in CRS, much stronger than the effects of conversion of other LULC types.
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Conservación de los Recursos Naturales , Ecosistema , China , Ciudades , Conservación de los Recursos Naturales/métodos , Humanos , AguaRESUMEN
On the basis of exploring the replicable, popularized and demonstrative accounting model of ecosystem value, it is critically needed to solve how to reasonably apply the accounting results of ecosystem value, form the application system of ecosystem value policy system, and promote the transformation of ecosystem service value from "accounting value" to "policy point". With the accounting of Fuzhou Gross Economic Ecological Product (GEEP) and Gross Ecosystem Product (GEP) as the starting point, we screened GEEP for indicators, calculated the green gold index and GEP per unit area, and analyzed the application mode in the policy and system design. The results showed that pollutant absorption, species conservation renewal energy values, wetland severe threat area proportion, air negative oxygen ions released volume, arable land occupancy rate, marine reclamation area proportion, carbon fixation quantity, oxygen release quantity, grassland cover change rate, coast protection area and environmental degradation cost of solid waste were the indicators significantly affecting the GEEP accounting results. The green gold index of Fuzhou City in 2015 and 2018 were 1.59 and 1.23, respectively, higher than that at the whole country level. The trends of GEP per unit area followed an order of wetland ecosystem> forest ecosystem> farmland ecosystem> grassland ecosystem> marine ecosystem. Based on the influencing factors of GEEP, green gold index and GEP per unit area, the management system and mode of "entering decision-making, planning, assessment and monitoring" of ecosystem values accounting results were constructed, which would provide a theoretical basis for the formation of a long-term mechanism for promoting the construction of ecological civilization in China.
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Conservación de los Recursos Naturales , Ecosistema , China , Ciudades , PolíticasRESUMEN
Ecological degradation accounting is a critical content of building green GDP and gross economic-ecological product (GEEP) accounting systems. With ecosystems in Fuzhou City as a research object, we built an accounting framework for the cost of ecological degradation according to the unreasonable human activity. Following the accounting framework, we calculated the ecological degradation cost in Fuzhou City of 2015 and 2018. The results showed that the ecological degradation cost in Fuzhou City of 2015 was 9.08 billion yuan, accounting for 1.6% of local GDP. For different ecosystem types, marine ecological degradation cost was the largest, about 6.311 billion yuan, accounting for 69.5% of the total loss, followed by wetland ecosystem, accounting for 28.7%, and then arable land, contributing only 1.8%. In term of functions, the cost of provisioning degradation was the largest, about 6.313 billion yuan, accounting for 69.5% of the total loss, followed by regulation loss, accounting for 27.5%, mainly from the loss of climate regulation and hydrological regulation. In the regional distribution, the ecological degradation cost was mainly concentrated in Lianjiang County, Luoyuan County, Fuqing City, and Minqing County, up to 8.092 billion yuan in total, accounting for 89.7% of total loss. Compared with 2015, the ecological degradation cost in 2018 decreased by 2.608 billion yuan, showing an obvious downward trend, with a decrease rate of 28.7%. The reductions were major in Lianjiang County (86.4%), Luoyuan County (14.8%), Fuqing City (19.9%), and Minqing County (12.6%), and mainly concentrated in marine and wetland ecosystems. Such a result indicated that people's awareness of ecological protection in Fuzhou City was increasing, and that the ecological damage due to human activity in marine and wetland system was obviously decreased. This study provided data support for promoting regional sustainable development and ecological civilization construction.
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Conservación de los Recursos Naturales , Ecosistema , China , Ciudades , Humanos , HumedalesRESUMEN
The gross economic-ecological product (GEEP) accounting is crucial to promote the construction of ecological civilization, and practice the ideas of "lucid waters and lush mountains are invaluable assets". GEEP accounting had been conducted at national and provincial scales, but not at urban scale. According to the economic and ecological development, the GEEP accounting framework was built in Fuzhou City. The GEEP value of Fuzhou City in 2015 and 2018 was calculated and the spatiotemporal variation was analyzed. The results showed that the GEEP value of Fuzhou City was 1208.568 billion yuan in 2015. Among which, the value of GDP and ecological regulation, and the cost of environmental degradation and ecological damage were 577.742, 636.420, 3.095 and 2.500 billion yuan, respectively. Minqing County had the highest GEEP, with a value of 170.022 billion yuan, which accounted for 14.1% of that in Fuzhou City. The lowered values were found in Fuqing City, Minhou County and Yongtai County, accounting for 12.2%, 12.1% and 10.4%, respectively. In 2018, the GEEP of Fuzhou City increased to 1445.399 billion yuan, with an increase rate of 19.6%, mainly due to the GDP increase (up by 47.4% from 2015). The highest proportions of GEEP were observed in Minqing County and Gulou District (12.0%), followed by Fuqing and Minhou counties (11.0%). Compared with 2015, the increase trends were observed for the total value of GEEP, unit area and per capita of GEEP values in Fuzhou City. The cost of environmental and ecological degradation in Fuzhou decreased by 7.2% and 12.4%, respectively, indicating that the overall ecological environment of Fuzhou was improving. The accounting of GEEP in Fuzhou could effectively make up for the shortage of GDP assessment at the urban scale in China. It could provide an instrument for Fuzhou government to formulate rational ecological civilization assessment system and promote regional sustainable development.
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Conservación de los Recursos Naturales , Ecosistema , China , CiudadesRESUMEN
The determination of regional ecological compensation quota and spatial selection are key issues in the study of horizontal transfer payment ecological compensation mechanism. Taking 12 districts of Fuzhou City as the basic research unit, we accounted the ecological function values of forest, grassland, wetland, agriculture, and marine ecosystems in 2015 and 2018. Combined with local economic development situation, we constructed an ecological compensation model. With this model, we determined the ecological compensation quota and spatial distribution of different ecosystems in various districts and counties of Fuzhou. The results showed that from 2015 to 2018, Gulou District had the largest ecological payment, with 36.384 billion yuan, followed by Mawei, Cangshan and Jin'an districts, with 7.809, 6.974 and 6.669 billion yuan, respectively. Luoyuan County and Taijiang District had lower payment, which were 2.942 and 1.903 billion yuan respectively. Among the areas requiring ecological compensation, Lianjiang County and Changle District had high compensation quotas, being 25.120 and 20.261 billion yuan, followed by Yongtai County (12.570 billion yuan). The compensation amounts in Minhou County, Fuqing City and Minqing County were less than 10 billion yuan. The distribution of ecological compensation differed across various ecosystems. In general, the main ecological compensation areas of forest, grassland, wetland and agriculture ecosystem were in Yongtai, Minqing, Minhou, Lianjiang and Luoyuan counties. The compensation amounts were 2.424-31.379 billion yuan in forest, 1.181-20.708 billion yuan in grassland, 1.015-45.493 billion yuan in wetland, and 5.780-23.954 billion yuan in cropland. The main regions that need compensation for marine ecosystem were Lianjiang County, Changle District, and Fuqing City, with the amount of compensation being 8.216-47.854 billion yuan. The results could properly reflect the coordinated development of regional ecological and economic conditions, which could provide a reference for the improvement of the ecological compensation mechanism in Fuzhou City.
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Conservación de los Recursos Naturales , Ecosistema , Ciudades , Bosques , HumedalesRESUMEN
Wetland plays an important role in ecological protection and social development. Scientific and rational evaluation of the values of wetland ecosystem service is the basis of protection and sustainable utilization of wetland resources. How to scientifically and effectively assess the wetland ecosystem gross ecosystem product (GEP) and make it into the national GDP accounting system are the focus of the scientific community and government departments. In this study, the accounting framework of wetland ecosystem GEP was constructed. Based on multi-source data and from the aspects of function and value, the accounting of wetland GEP in Fuzhou City was carried out. The results showed that the GEP of wetland ecosystem in Fuzhou City was 239.23 billion yuan in 2015. Such value mainly came from the ecological regulation service value (157.869 billion yuan), which accounted for 66.0% of the total and was about 2.2 and 15.6 times of the product supply service value and cultural service value. Among the ecological regulation services of wetlands, hydrodynamic regulation service and climate regulation service were the highest. Together, they accounted for 82.9% of the ecological regulation service value. The ecological regulation value per unit area of wetland in Fuzhou City was 1347.8 thousand yuan·hm-2, which was higher than the mean level of the whole country. In the districts and counties of Fuzhou City, the value of wetland ecosystem in Minqing County was the largest, about 88.83 billion yuan, accounting for 40.1% of the total value of product supply and ecological regulation. In terms of types, coastal wetlands in Fuzhou City had the largest function of ecological regulation services, which was about 2.5 times of that of river wetlands and constructed wetlands. The accounting of GEP of wetland ecosystem in Fuzhou City is an important practice for the conviction of "lucid waters and lush mountains are invaluable assets", which would provide technical support for guiding local government to scientifically manage wetland ecosystem.
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Ecosistema , Humedales , Ciudades , Conservación de los Recursos Naturales , RíosRESUMEN
Facility agriculture, a typical agricultural production management mode, could affect carbon cycle due to its unique production environmental conditions and highly intensive utilization. With the five main sources as accounting objects, including agricultural film investment, energy consumption, pesticide and fertilizer application, CO2 fertilizer application, and facility soil, we estimated the amount and intensity of carbon emission of three facility agriculture (continuous greenhouse, solar greenhouse, and plastic greenhouse) in 31 provinces in 2018. The results showed that the total carbon emission of facility agriculture in China was 210.3817 million t CO2e, with the three facility agriculture types of plastic greenhouse, solar greenhouse, and continuous greenhouse accounting for 60.2%, 37.4% and 2.4%, respectively. Carbon emission of facility agriculture was mainly contributed by soil greenhouse gas, agricultural film and supplies investment. Carbon emission per unit area of continuous greenhouses was significantly lower than that of solar and plastic greenhouses. The scientific capital allocation rate and facility agriculture scale were the two main factors influencing the carbon emission in facility agriculture. Based on all the results, we presented the carbon emission reduction path from the three perspectives of improving the scientific investment, material consumption utilization rate, and facility area utilization rate of facility agriculture.
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Agricultura , Carbono , Ciclo del Carbono , Fertilizantes , SueloRESUMEN
With the continuous development of China's society and economy, the breadth and depth of cultivated land resources development and utilization have been continuously expanded, while the production efficiency and scale of cultivated land gradually have been improved. There were rapidly increases of carbon emission induced from cultivated land management, such as the agricultural inputs and energy consumptions. Taking carbon emission from cultivated land utilization in Northeast China as the research object, we determined the carbon emission accounting framework system according to the life cycle method. Based on estimation results of carbon emissions from 1979 to 2015 in Northeast China, the driver factor system affecting agricultural carbon emissions was constructed using logarithmic mean Divisia index model and the influence mechanism of cultivated land carbon emissions in Northeast China was deeply explored. The results showed that total carbon emission from cultivated land utilization in 2015 was 21.9% higher than that in 1979 and carbon emission intensity in 2015 was 1.54 t·hm-2 lower than that in 1979. Soil management and agricultural inputs were the main sources of carbon emissions from cultivated land accounting for 83.6% of the total carbon emissions. The increases of land productivity and science and technology fund allocation rate were found to be the driving factors of carbon emission from cultivated land utilization. On the contrary, the reduction of input/output ratio, cultivated land area per capita and intensity of science and technology investment decreased carbon emission from cultivated land utilization.
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Agricultura , Carbono , Carbono/análisis , Dióxido de Carbono/análisis , China , SueloRESUMEN
The COVID-19 pandemic is impacting human activities, and in turn energy use and carbon dioxide (CO2) emissions. Here we present daily estimates of country-level CO2 emissions for different sectors based on near-real-time activity data. The key result is an abrupt 8.8% decrease in global CO2 emissions (-1551 Mt CO2) in the first half of 2020 compared to the same period in 2019. The magnitude of this decrease is larger than during previous economic downturns or World War II. The timing of emissions decreases corresponds to lockdown measures in each country. By July 1st, the pandemic's effects on global emissions diminished as lockdown restrictions relaxed and some economic activities restarted, especially in China and several European countries, but substantial differences persist between countries, with continuing emission declines in the U.S. where coronavirus cases are still increasing substantially.
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Contaminantes Atmosféricos/análisis , Dióxido de Carbono/análisis , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Contaminantes Atmosféricos/economía , Betacoronavirus , COVID-19 , Dióxido de Carbono/economía , Infecciones por Coronavirus/economía , Infecciones por Coronavirus/prevención & control , Monitoreo del Ambiente , Combustibles Fósiles/análisis , Combustibles Fósiles/economía , Humanos , Industrias/economía , Dióxido de Nitrógeno/análisis , Dióxido de Nitrógeno/economía , Pandemias/economía , Pandemias/prevención & control , Neumonía Viral/economía , Neumonía Viral/prevención & control , SARS-CoV-2RESUMEN
A Correction to this paper has been published: https://doi.org/10.1038/s41467-020-20254-5.
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Carbon emissions due to land use change have an important impact on global climate change. Adjustment of regional land use patterns has a great scientific significance to adaptation to a changing climate. Based on carbon emission/absorption parameters suitable for Liaoning Province, this paper estimated the carbon emission of land use change in the city and town concentrated area of central Liaoning Province. The results showed that the carbon emission and absorption were separately 308.51 Tg C and 11.64 Tg C from 1997 to 2010. It meant 3.8% of carbon emission. was offset by carbon absorption. Among the 296.87 Tg C net carbon emission of land use change, carbon emission of remaining land use type was 182.24 Tg C, accounting for 61.4% of the net carbon emission, while the carbon emission of land use transformation was 114.63 Tg C, occupying the rest 38.6% of net carbon emission. Through quantifying the mapping relationship between land use change and carbon emission, it was shown that during 1997-2004 the contributions of remaining construction land (40.9%) and cropland transform ation to construction land (40.6%) to carbon emission were larger, but the greater contributions to carbon absorption came from cropland transformation to forest land (38.6%) and remaining forest land (37.5%). During 2004-2010, the land use types for carbon emission and absorption were the same to the period of 1997-2004, but the contribution of remaining construction land to carbon emission increased to 80.6%, and the contribution of remaining forest land to carbon absorption increased to 71.7%. Based on the carbon emission intensity in different land use types, we put forward the low-carbon regulation countermeasures of land use in two aspects. In carbon emission reduction, we should strict control land transformation to construction land, increase the energy efficiency of construction land, and avoid excessive development of forest land and water. In carbon sink increase, we should improve forest coverage rate, implement cropland, grassland transform to forest land, strengthen forest land and water protection, and adjust cropland internal structure and scientifically implement cropland management.
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Agricultura , Secuestro de Carbono , Carbono/análisis , Ciudades , Bosques , China , Cambio Climático , Monitoreo del AmbienteRESUMEN
China, as a fast growing fossil-fuel-based economy, experiences increasing levels of air pollution. To tackle air pollution, China has taken the first steps by setting emission-reduction targets for nitrogen oxides (NO x ) and sulphur dioxide (SO2) in the 11th and 12th Five Year Plans. This paper uses two models-the Energy-Environment-Economy Model at the Global level (E3MG) and the global Chemistry Transport Model pTOMCAT-to test the effects of these policies. If the policy targets are met, then the maximum values of 32 % and 45 % reductions below 'business as usual' in the monthly mean NO x and SO2 concentrations, respectively, will be achieved in 2015. However, a decrease in NO x concentrations in some highly polluted areas of East, North-East and South-East China can lead to up to a 10% increase in the monthly mean concentrations in surface ozone in 2015. Our study demonstrates an urgent need for the more detailed analysis of the impacts and designs of air pollution reduction guidelines for China.
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Contaminantes Atmosféricos/análisis , Contaminación del Aire/prevención & control , Óxidos de Nitrógeno/análisis , Ozono/análisis , Dióxido de Azufre/análisis , China , Ciudades , Modelos Teóricos , Planificación SocialRESUMEN
Land use types of the Tiexi old industrial district, Shenyang, Northeast China were derived from QUICKBIRD and IKONOS satellite image interpretation to analyze its dynamics and intensive use by geostatistics and convention statistical methods which could reveal regional environment and socio-economic services. The results showed the main land use types were industrial land and residential land in Tiexi old industrial district. Land use changed significantly from 2000-2010, i. e., the industrial land area decreased rapidly and the housing land area, park land, commercial service land, and grassland increased simultaneously. The district environment was improved and the comprehensive livable level was increasing. Also, the regional functional orientation was becoming clear, the living and business function verged to maturity, and the land use efficiency was increasing. From 2002, the intensive land use level in Tiexi old industrial district was evidently improved, however, the potential of intensive land use could still be further exploited.