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Because of the alkaline nature and high calcium content of cements in general, they serve as a CO 2 -absorbing agent through carbonation processes, resembling silicate weathering in nature. This carbon uptake capacity of cements could abate some of the CO 2 emitted during their production. Given the scale of cement production worldwide (4.10 Gt in 2019), a life-cycle assessment is necessary to determine the actual net carbon impacts of this industry. We adopted a comprehensive analytical model to estimate the amount of CO 2 that had been absorbed from 1930 to 2019 in four types of cement materials, including concrete, mortar, construction waste, and cement kiln dust (CKD). In addition, the process CO 2 emission during the same period based on the same datasets was also estimated. The results show that 21.02 Gt CO 2 (95 % confidence interval, CI: 18.01–24.41 Gt CO 2 ) had been absorbed in the cements produced from 1930 to 2019, with the 2019 annual figure mounting up to 0.89 Gt CO 2 yr −1 (95 % CI: 0.76–1.06 Gt CO 2 ). The cumulative uptake is equivalent to approximately 55 % of the process emission based on our estimation. In particular, China's dominant position in cement production or consumption in recent decades also gives rise to its uptake being the greatest, with a cumulative sink of 6.21 Gt CO 2 (95 % CI: 4.59–8.32 Gt CO 2 ) since 1930. Among the four types of cement materials, mortar is estimated to be the greatest contributor (approximately 59 %) to the total uptake. Potentially, our cement emission and uptake estimation system can be updated annually and modified when necessary for future low-carbon transitions in the cement industry. All the data described in this study, including the Monte Carlo uncertainty analysis results, are accessible at https://doi.org/10.5281/zenodo.4459729 (Wang et al., 2021).

Industry is the largest consumer of energy and CO2 emission sector. Recognizing the heterogeneity of total factor CO2 emission performances between various industrial sub-sectors is crucial for governments, to enable the compilation of effective industrial CO2 emission reduction policies. To determine the CO2 emission characteristics throughout the industry sectors, Liaoning province was selected as typical heavy industry province for analysis. Based on the input-output data of 37 industrial sub-sectors from 2003 to 2012, the industrial total factor CO2 emission efficiencies and performances were analyzed through data envelopment analysis (DEA) and the Malmquist-Luenberger productivity index. The results show that most sub-sectors have low total factor CO2 emission efficiencies, which indicates that it is difficult for Liaoning’s industry to reduce carbon emissions. The total factor CO2 emission performance of the overall industry declined by 1.85% per year during the study period; this decrease was mainly related to a lack in implementing technical changes. However, efficiency change showed a progressive trend. These findings indicate that to realize carbon reduction in heavy industry provinces within China, it is necessary to focus on expediting technical change.

The effect of greenhouse soil management on soil aggregation and sesquioxides cycling should be evaluated to maximize the benefits of solar greenhouses rationally. The aggregation process of long-t...

Building lifetime is a crucial parameter for modelling building stock's turnovers and related dynamics of embodied and operational energy demand. However, it is poorly characterized and often based on assumptions (especially for developing countries such as China), because no or few empirical data are available. Here we combined a top-down dynamic material flow analysis method with bottom-up information (i.e., age profile of residential building stock, per capita residential floor area, and population) to calibrate the lifetimes of Chinese buildings from 1950 to 2015. We contrasted the top-down estimates with existing literature and primary data from on-site surveys to verify the plausibility of calibrated building lifetimes. We found an overall downward trend of building lifetimes during 1950-1989 and a gradual climb-up since 1990s. However, the present Chinese building lifetime appears still far below the design lifetime (50 years). Up to 2015, the floor areas of Chinese building stock has reached an enormous level of 64.7 billion m(2); on the per capita basis, it has reached 30.5 and 15.7 m(2) for residential and non-residential use, respectively. The yearly demolished floor areas have reached at a level of 1.6 billion m(2). The improved building lifetimes can enhance our understanding of building stock's turnovers and vintage-based energy performance and thus help better characterize life cycle energy demand of building stocks and beyond. To further the use of the calibrated building lifetimes, modelers and data users should also be aware of the variable building lifetimes and have a structured overview of data sources and their inconsistency.

Author(s): Liu, Zhu; Ciais, Philippe; Deng, Zhu; Lei, Ruixue; Davis, Steven J; Feng, Sha; Zheng, Bo; Cui, Duo; Dou, Xinyu; Zhu, Biqing; Guo, Rui; Ke, Piyu; Sun, Taochun; Lu, Chenxi; He, Pan; Wang, Yuan; Yue, Xu; Wang, Yilong; Lei, Yadong; Zhou, Hao; Cai, Zhaonan; Wu, Yuhui; Guo, Runtao; Han, Tingxuan; Xue, Jinjun; Boucher, Olivier; Boucher, Eulalie; Chevallier, Frederic; Tanaka, Katsumasa; Wei, Yiming; Zhong, Haiwang; Kang, Chongqing; Zhang, Ning; Chen, Bin; Xi, Fengming; Liu, Miaomiao; Breon, Francois-Marie; Lu, Yonglong; Zhang, Qiang; Guan, Dabo; Gong, Peng; Kammen, Daniel M; He, Kebin; Schellnhuber, Hans Joachim | Abstract: A Correction to this paper has been published: https://doi.org/10.1038/s41467-020-20254-5.

Because of the alkaline nature and high calcium content of cements in general, they serve as a CO2 absorbing agent through carbonation processes, resembling silicate weathering in nature. This carbon uptake capacity of cements could abate some of the CO2 emitted during their production. Given the scale of cement production worldwide (4.10 Gt in 2019), a life-cycle assessment is necessary in determining the actual net carbon impacts of this industry. We adopted a comprehensive analytical model to estimate the amount of CO2 that had been absorbed from 1930 to 2019 in four types of cement materials including concrete, mortar, construction waste and cement kiln dust (CKD). Besides, the process CO2 emission during the same period based on the same datasets was also estimated. The results show that 21.12 Gt CO2 (18.12–24.54 Gt CO2, 95 % CI) had been absorbed in the cements produced from 1930 to 2019, with the 2019 annual figure mounting up to 0.90 Gt CO2 yr−1 (0.76–1.07 Gt CO2, 95 % CI). The cumulative uptake is equivalent to approx. 52 % of the process emission, based on our estimation. In particular, China's dominant position in cement production/consumption in recent decades also gives rise to its uptake being the greatest with a cumulative sink of 6.21 Gt CO2 (4.59–8.32 Gt CO2, 95 % CI) since 1930. Among the four types of cement materials, mortar is estimated to be the greatest contributor (approx. 58 %) to the total uptake. Potentially, our cement emission and uptake estimation system can be updated annually and modified when necessary for future low-carbon transitions in the cement industry. All the data described in this study, including the Monte Carlo uncertainty analysis results, are accessible at https://doi.org/10.5281/zenodo.4064803.

Boreal wetlands are significant natural sources of methane (CH4) to the atmosphere, and are vulnerable to freezing-thawing cycles (FTC). Nonetheless, the underlying factors that induce CH4 emission in boreal wetlands during FTC are still unclear. Our goal was to characterize soil CH4 emission potential from a freshwater marsh as impacted by FTC and to determine the corresponding mechanisms. We collected soil samples from two soil layers (0–20 and 20–40 cm) of an undisturbed freshwater marsh in Sanjiang Plain, Northeast China, and subjected them to various freezing (6 to −6 °C) and thawing (−6 to 6 °C) cycles. Soil CH4 emission, DOC, and the aromaticity and complexity of DOC indexes were monitored. The results showed that FTC significantly increased CH4 emission potential in the 0–20 cm surface soil layer. The maximum hourly CH4 emission rate was 55.0 mg C m−2 h−1, approximately 19 times as high as that of the unfrozen control sample (2.8 mg C m−2 h−1). However, the peak intensity of CH4 emission decreased when the numbers of FTC increased. Meanwhile, FTC not only increased the quantity of DOC released, but also enhanced its instability via increasing the contribution of relatively small, readily degradable organic molecules. Additionally, the CH4 emission potential was significantly correlated with the aromaticity and complexity of DOC, indicating that the release of labile substrates under FTC was one important factor controlling the microbial production of CH4 and the high emissions upon thawing. Our study suggested that global warming-induced increases in seasonal FTC in boreal wetlands may increase CH4 emissions beyond what would occur from long-term temperature increases alone.

Soil in greenhouses is likely to suffer a gradual decline in aggregate stability. Determination of the effects of different fertiliser practices on soil aggregate stability is important for taking advantage of solar greenhouses. Soil aggregate stability and iron (Fe) and aluminium (Al) oxide contents were investigated in a 26-year long-term fertilisation experiment in greenhouse in Shenyang, China, under eight fertiliser treatments: manure (M), fertiliser N (FN), fertiliser N with manure (MN), fertiliser P (FP), fertiliser P with manure (MP), fertiliser NP (FNP), fertiliser NP with manure (MNP), and control without any fertiliser (CK). A wet sieving method was used to determine aggregate size distribution and water-stable aggregates (WSA), mean weight diameter and geometric mean diameter as the indices of soil aggregate stability. Different fertiliser treatments had a statistically significant influence on aggregate stability and Fe and Al oxide contents. Long-term application of inorganic fertilisers had no obvious effects on the mass proportion of aggregates. By contrast, manure application significantly increased the mass proportion of macroaggregates at the expense of microaggregates. All treatments, with the exception of FNP, significantly increased the stability of macroaggregates but decreased that of microaggregates when compared with CK. Aggregation under MP and MN was better than that under M and MNP; however, no significant differences were found among inorganic fertiliser treatments ( i.e ., FN, FP, and FNP). A positive relation was found between pyrophosphate-extractable Fe and WSA ( r = 0.269), but no significant relations were observed between other Fe and Al oxides and aggregate stability.

Greenhouse gases emissions from biomass burning have been given a little attention, especially the spatiotemporal features of biomass burning sources and greenhouse gases emissions have not been comprehensively uncovered. This research undertook IPCC bottom-up inventory guideline to estimate Chinese greenhouse gases emissions from biomass burning and applied geographical information system to reveal biomass burning emissions spatiotemporal features. The purposes were to quantify greenhouse gases emissions from various biomass burning sources and to uncover the spatial and temporal emissions features so to deliver future policy implications in China. The results showed that the average annual biomass burning emissions in China from 2000-2012 were 880.66 Mt for CO_2, 96.59 Mt CO_2-eq for CH_4, and 16.81 Mt CO_2-eq for N_2O. The spatial pattern of biomass greenhouse gases emissions showed about 50 % of national emission were in the east and south-central regions. The majority of biomass burning emissions were from firewood and crop residues, which accounted for more than 90 % of national biomass burning emissions. All types of biomass burning emissions exhibited similar temporal trends from 2000-2012, with strong inter-annual variability and fluctuant increase. The large grassland and forest fires induced the significant greenhouse gases emissions peaks in the years of 2001, 2003 and 2006. We found that biofuel burning, with low combustion efficiency, is the major emission source. Open burning of biomass was widespread in China, and east and south-central regions were the major distribution of biomass burning greenhouse gases emission. Optimized design for improving the efficiency of biomass utilization and making emission control policy combination with its spatiotemporal features will be the effective way to reduce the biomass burning emissions.

This study investigated estimation on ecosystem services value based on food production in Xinjian County of Nanchang City, East China. We used two Landsat TM data sets (1996, 2004) to estimate changes in the size of seven land use categories and we used the most recently published value equivalent to estimate changes in the values of ecosystem services. The total value of ecosystem services in Xinjian County was 4588.2 million Yuan in 1996 and 4587.8 million Yuan in 2004, with a decrease of 340.8 thousand Yuan mainly due to the relatively biggish decrement in values of ecosystem service functions for waste treatment, hydrology regulation and food production, although the values for all the other six ecosystem service functions showed an escalating trend from 1996 to 2004. We concluded that future local land use plan should give priority to the conservation of these reductive ecosystems, in order to promote and maintain the balance of local ecosystem.

In order to uncover driving forces for provincial CO2 emission in China, a case study was undertaken to shed light on the CO2 emission growth in such a region. Liaoning province was selected due to its typical features as one industrial province. The environmental input–output analysis and structure decomposing analysis have been conducted in order to provide a holistic picture on Liaoning's CO2 emissions during 1997–2007. Research outcomes indicate that rapid increase of per capita consumption activities is the main driver for Liaoning to have a significant CO2 emission growth, followed by consumption structure, production structure and population size. Energy intensity and energy structure partly offset the CO2 emission increase. Electricity power and heat supply and construction sectors caused the most CO2 emission, indicating that more specific mitigation policies for these two sectors should be prepared. From final demand point of view, it is clear that trade plays a leading role in regional CO2 emission, followed by fixed capital investment and urban household consumption which become increasingly important over time. Consequently, in order to realize low carbon development, local governments should consider all these factors so that appropriate mitigation policies can be raised by considering the local realities.

The combustion of fossil fuel contributes to not only global warming but also the emissions of air pollutants. In China, the rapid growth of energy consumption leads to a large quantity of greenhouse gas (GHG) and air pollutant emissions. Although many measures have been proposed by the local governments to mitigate the GHG emissions and improve air quality, limited economic resources slow the efforts of the local government to implement measures to control both types of emissions. The co-benefits approach can use resources efficiently to solve multiple environmental problems. In this study, we first calculated the CO2 and air pollutants (SO2, NOx and PM2.5) emissions in Xinjiang Uygur Autonomous Region. Then, the co-benefits of wind power, including mitigation of CO2 and air pollutants (SO2, NOx and PM2.5) emissions and water savings, were assessed and quantified in the Xinjiang Uygur Autonomous Region. The results demonstrate that, during the 11th five-year period (2006–2010), emissions mitigation by wind power accounted for 4.88% (1065 × 104 t) of CO2, 4.31% (4.38 × 104 t) of SO2, 8.23% (3.41 × 104 t) of NOx and 4.23% (0.32 × 104 t) of PM2.5 emission by the thermal power sector. The total economic co-benefits of wind power accounted for 0.46% (1.38 billion 2009US$) of the GDP of Xinjiang during 2006–2010.

Industrial parks have become the effective strategies for government to promote sustainable economic development due to the following advantages: shared infrastructure and concentrated industrial activities within planned areas. However, due to intensive energy consumption and dependence on fossil fuels, industrial parks have become the main areas for greenhouse gas emissions. Therefore, it is critical to quantify their carbon footprints so that appropriate emission reduction policies can be raised. The objective of this paper is to seek an appropriate method on evaluating the carbon footprint of one industrial park. The tiered hybrid LCA method was selected due to its advantages over other methods. Shenyang Economic and Technological Development Zone (SETDZ), a typical comprehensive industrial park in China, was chosen as a case study park. The results show that the total life cycle carbon footprint of SETDZ was 15.29 Mt, including 6.81 Mt onsite (direct) carbon footprint, 8.47 Mt upstream carbon footprint, and only 3201 t downstream carbon footprint. Analysis from industrial sector perspectives shows that chemical industry and manufacture of general purpose machinery and special purposes machinery sector were the two largest sectors for life cycle carbon footprint. Such a sector analysis may be useful for investigation of appropriate emission reduction policies.

China's rapid urbanization and industrialization has resulted in many urban brownfields.To limit urban sprawl and avoid use of valuable greenfields, brownfield redevelopment has become a development strategy for Chinese cities. However, poor understanding of brownfield redevelopment has led many urban planners to pay scant attention to brownfield site soil contamination. This inattentiveness has led to both ecological and residential health risks. Investigating soil quality is necessary for effective urban ecological system design and mitigation. This paper investigates spatial allocation and concentrations of polycyclic aromatic hydrocarbons (PAHs) in the city of Shenyang through a case study in its former Tiexi industrial region, a typical brownfield redevelopment site. The research findings indicate that serious PAHs pollution exists due to previous and current industrial activities and transportation volatile emissions. These types of research findings are critical to ecological engineering efforts that need to incorporate local stakeholders and ecology so that an integrated effort can be made to mitigate the impacts of PAHs.

Medical waste management is of great impor- tance due to its potential environmental and public health risks, especially in developing countries where both financial and technological resources on medical waste management are still lacking. Although many studies have focused on country-scaled medical waste management, few have paid close attention to regional (city-scale) manage- ment, particularly in China. This paper fills such a gap by employing a case study approach. Due to its representative nature, Shenyang was selected as the case study. After a review of China's medical waste management, an empiri- cal study in Shenyang was conducted in order to analyze the current state as well as identify key challenges on regional medical waste management. Based upon the local realities and aiming to better manage medical wastes, an integrated medical waste management framework is developed. Such a platform encourages the establishment of a specific medical waste management authority, a city scaled capacity building program on improving the general public's awareness, an information platform, application of state-of-the-art technologies, as well as creation of an effective financial system. The combination of such ini- tiatives can significantly improve the overall eco-efficiency of medical waste management at the regional level and should be promoted to other developing cities.

Calcination of carbonate rocks during the manufacture of cement produced 5% of global CO 2 emissions from all industrial process and fossil-fuel combustion in 2013. Considerable attention has been paid to quantifying these industrial process emissions from cement production, but the natural reversal of the process - carbonation - has received little attention in carbon cycle studies. Here, we use new and existing data on cement materials during cement service life, demolition, and secondary use of concrete waste to estimate regional and global CO 2 uptake between 1930 and 2013 using an analytical model describing carbonation chemistry. We find that carbonation of cement materials over their life cycle represents a large and growing net sink of CO 2, increasing from 0.10 GtC yr â '1 in 1998 to 0.25 GtC yr â '1 in 2013. In total, we estimate that a cumulative amount of 4.5 GtC has been sequestered in carbonating cement materials from 1930 to 2013, offsetting 43% of the CO 2 emissions from production of cement over the same period, not including emissions associated with fossil use during cement production. We conclude that carbonation of cement products represents a substantial carbon sink that is not currently considered in emissions inventories., Supported by the NSFC (41473076, 41501605, 51578344, 31100346, 41629501, 71533005), Fund of Youth Innovation Promotion Association, Chinese Academy of Sciences, Fund of Fellowships for Young International Distinguished Scientists in Institute of Applied Ecology, Chinese Academy of Sciences, National Key R&D Program of China (2016YFA0602604), the UK Economic and Social Research Council funded project ‘Dynamics of Green Growth in European and Chinese Cities’ (ES/L016028/1), and the UK Natural Environment Research Council funded project ‘Integrated assessment of the emission-health-socioeconomics nexus and air pollution mitigation solutions and interventions in Beijing’ (NE/N00714X/1).

With China’s rapid economic development and urbanization process, cities are facing great challenges for tackling anthropogenic climate change. In this paper we present features, trajectories and driving forces for energy-related greenhouse gas (GHG) emissions from four Chinese mega-cities (Beijing, Tianjin, Shanghai and Chongqing) during 1995–2009. First, top-down GHG inventories of these four cities, including direct emissions (scope 1) and emissions from imported electricity (scope 2) are presented. Then, the driving forces for the GHG emission changes are uncovered by adopting a time serial LMDI decomposition analysis. Results indicate that annual GHG emission in these four cities exceeds more than 500 million tons and such an amount is still rapidly growing. GHG emissions are mainly generated from energy use in industrial sector and coal-burning thermal power plants. The growth of GHG emissions in four mega-cities during 1995–2009 is mainly due to economic activity effect, partially offset by improvements in carbon intensity. Besides, the proportion of indirect GHG emission from imported energy use (scope 2) keeps growing, implying that big cities are further dependent on energy/material supplies from neighboring regions. Therefore, a comprehensive consideration on various perspectives is needed so that different stakeholders can better understand their responsibilities on reducing total GHG emissions.

Cities consumed 84% of commercial energy in China, which indicates cities should be the main areas for GHG emissions reduction. Our case study of Shenyang in this paper shows how a clear inventory analysis on GHG emissions at city level can help to identify the major industries and societal sectors for reduction efforts so as to facilitate low-carbon policy-making. The results showed total carbon emission in 2007 was 57 Mt CO2 equivalents (CO2e), of which 41 Mt CO2e was in-boundary emissions and 16 Mt CO2e was out-of-boundary emissions. The energy sector was dominant in the emission inventory, accounting for 93.1% of total emissions. Within energy sector, emissions from energy production industry, manufacturing and construction industry accounted for 88.4% of this sector. Our analysis showed that comparing with geographical boundary, setting system boundary based on single process standard could provide better information to decision makers for carbon emission reduction. After attributing electricity and heating consumption to final users, the resident and commercial sector became the largest emitter, accounting for 28.5% of total emissions. Spatial analysis of emissions showed that industrial districts such as Shenbei and Tiexi had the large potential to reduce their carbon emissions. Implications of results are finally discussed.

This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River watershed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GIS) technology. Then, using the famous land-use change model of Conversion of Land Use and its Effects at Small regional extent (CLUE-S), this paper simulated the land use changes under historical trend (HT), urban planning (UP) and ecological protection (EP) scenarios considering urban planning and ecological protection over the next 20 years. The simulated results under UP scenario in 2020 were compared with the planning map to assess the feasibility of using land-use change model to guide regional planning. Results show that forest land, dry farmland, paddy, and shrub land were the main land-use categories. Paddy and dry farmland being converted to urban area and rural settlement characterized the land-use change from 1988 to 2004. The main land-use categories changed over time. Landscape-pattern fragmentation will be worse under HT and UP scenarios, but better in EP scenario. The comparing results of simulated map with planning map in 2020 show that land-use change model is powerful tool to guide regional planning. Land-use scenarios can support regional planning and policy-making through analyzing future consequences scientifically.

With the increasing attention on developing a low-carbon economy, it is necessary to seek appropriate ways on reducing greenhouse gas (GHG) emissions through innovative municipal solid waste management (MSWM), such as urban symbiosis. However, quantitative assessments on the environmental benefits of urban symbiosis, especially in developing countries, are limited because only a limited number of planned synergistic activities have been successful and it is difficult to acquire detailed inventory data from private companies. This paper modifies and applies a two-step simulation system and used it to assess the potential environmental benefits, including the reduction of GHG emissions and saving of fossil fuels, by employing various Japanese plastics recycling/energy-recovery technologies in Shenyang, China. The results showed that among various recycling/energy-recovery technologies, the mechanical waste plastics recycling technology, which produces concrete formwork boards (NF boards), has the greatest potential in terms of reducing GHG emissions (1.66 kg CO(2)e/kg plastics), whereas the technology for the production of refuse plastic fuel (RPF) has the greatest potential on saving fossil fuel consumption (0.77 kg ce/kg-plastics). Additional benefits can be gained by applying combined technologies that cascade the utilization of waste plastics. Moreover, the development of clean energy in conjunction with the promotion of new waste plastics recycling programs could contribute to additional reductions in GHG emissions and fossil fuel consumption.

The distribution and stability of soil aggregates and its relation to iron oxide during different plantation years are studied in a solar greenhouse. Soil samples were obtained from a vetatable bed within a greenhouse in Xinmin (Liaoning, China). The composition, water stability and percentage of aggregate destruction, as well as variations in different forms of iron oxides were evaluated at 5 time points (0, 2, 5, 8 and 16 years). Soil from a dry land in an open field was also collected for comparison. The quantity and water stability of >0.25 mm soil aggregates from 2 and 5 years were lower than those in the soil from the open field. These parameters significantly increased after five years. The contents of non-free iron oxides decreased under greenhouse cultivation, resulting in reduced aggregate stability. Free iron oxides were positively associated with >2 mm aggregates. Complex iron oxides were positively correlated with 2–0.25 mm and 0.25–0.053 mm aggregates but negatively correlated with

This paper presents a study of the relationship between phosphorus fractions and phosphorus release in the presence of manure. Dynamic changes in the characteristics of total phosphorus in surface water are simulated by waterlogged incubation. The study was carried out by comparing sterilized and non-sterilized treatments to analyze the effect of manure on the dynamics of phosphorus (P) release from soil. Experimental results show that manure application in paddy soil can significantly increase the content of phosphorus fractions (p

The SLEUTH urban growth model was used to simulate future urban growth patterns and to explore potential environmental impacts of urban development under different conditions of development in Shenyang City, China. The SLEUTH model was calibrated with historical data (1988–2004) extracted from a time series of TM satellite images, and the future growth was projected out to 2030 assuming three different policy scenarios: (1) current trends scenario (Scenario CT), (2) regional policy and urban planning scenario (Scenario PP), and (3) environmental protection scenario (Scenario EP). Scenario analysis showed that urban growth would accelerate under all policy scenarios with significant differences in development pattern and sustainability after 2016. Urban development under Scenario CT would lead to substantial loss of resource lands than that under the other two scenarios, and the urban landscape pattern would be increasingly complex and dispersed. In contrast, urban growth under scenario PP and EP would consume less natural resource land and show a relatively compact urban development pattern during the prediction period. This study suggested that it is crucial to take stringent urban planning and management measures to control future urban growth and to protect primary farmland and the support system of urban ecology in Shenyang City. The SLEUTH model is a useful planning tool to guide sustainable utilization of urban land resources to a certain extent.

Chinese cities are undergoing rapid urban sprawl, dramatic landscape change, industrialisation, and ecological damage, which threaten urban sustainable development. The aim of our research was to answer the following question: is it possible to achieve sustainable development through rational ecological protection policies that harmonise future urbanisation, re‐industrialisation, economic development, and sustainable urban land use in these cities? To answer the question, we conducted a simulation of policy impacts on future urban growth and landscape change. We applied a widely used regional assessment and predictive model, SLEUTH, to explore the potential impacts of different ecological protection policy scenarios in the Shenyang-Fushun metropolitan region of China. Future urban growth and landscape changes were projected out to 2050, assuming three different ecological protection policy scenarios: (1) accelerated urban development (AUD), (2) managed urban development (MUD), and (3) limited urban develo...

Performance evaluation is crucial for the development and improvement of an urban cellular automata model, such as SLEUTH. In this paper, we employed multiple methods for map comparison and model validation to evaluate the simulation performance of the SLEUTH urban growth model in the Shenyang metropolitan area of China. These multiple methods included the relative operating characteristic (ROC) curve statistic, multiple-resolutions error budget, and landscape metrics. They were used to quantitatively examine model performance in terms of the amount and spatial location of urban development, urban spatial pattern and prediction ability. The assessment results showed that SLEUTH performed well in the way of the quantitative simulation of urban growth for this case study. Similar to other urban growth models, however, the simulation accuracy for spatial location of new development at the pixel scale and urban spatial pattern still needs to be improved greatly. These inaccuracies might be attributed to the structure and nature of SLEUTH, local urban development characteristics, and the temporal and spatial scale of its application. Finally, many valuable suggestions had been put forward to improve simulation performance of SLEUTH model for spatial location of urban development in the Shenyang metropolitan area.

© 2015 Macmillan Publishers Limited. All rights reserved. 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).

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.

China's “building a new countryside” strategy for coordinating urban and rural development and gearing up national economic growth brings challenges to the country's farmland protection. The objective of this study is to evaluate potential impacts of implementing the strategy on farmland and to provide scientific guidelines and decision support for decision makers in northeast China. We analyzed three “building a new countryside” implementation scenarios (Historical Trend, Intensive Development, and Extensive Development) using the SLEUTH urban growth and land cover change model in combination with remote sensing and GIS analysis. The results indicated that farmland loss was inevitable, but revealed large differences in landscape patterns and the amount of farmland loss among the three BNC implementation scenarios. The Extensive Development scenario showed the largest increase in urban and rural residential land, the highest level of landscape fragmentation, and the largest loss of farmland. Farmland loss under the Intensive Development scenario is higher than that under the Historical Trend scenario; however, urban and rural sprawl and the fragmentation of landscape under the Intensive Development scenario were lower than those under the Historical Trend scenario. Consequently, the Intensive Development scenario was recommended for actual “building a new countryside” implementation in the study area. Potential rural sprawl under the Intensive Development scenario was also discussed, which provided useful information for guiding scientific-based decision support and policy making. While most studies of sprawl prediction involve urban centers only, our study presents a case of predicting urban and rural sprawl simultaneously.

Waste is an inevitable byproduct of human activity. In the last two centuries, waste management has passed through a series of transitions in terms of treatment and disposal technologies, as well as in administrative systems and in people’s attitudes. Waste managers, engineers, planners, and researchers have contributed to these transitions by responding to issues such as public health, disposal capacity, more-rigorous environmental standards, and public and political pressures (Louis, 2004; Tarr, 1985). More recently, studies on waste management have emphasized the 3Rs (Reduce, Reuse, and Recycle). As a result of the efforts of practitioners and researchers, considerable achievements in waste handling have been realized in a number of countries. The questions that we currently face are “What forthcoming issues related to waste management do we need to respond to?” and “What will be the appropriate methods for addressing these issues in research?” In this chapter, we will explore some of the pressing issues, and we will propose a research framework for assessing the options available for responding to them.

Shenyang and Fushun are two most nearest mega cities in China. Integration of the two cities as one sub-administrative economic region is a state and province policy to promote economy development of Liaoning province. How the urban patterns of the mega cities will grow is interested to city planners, decision-makers, land managers, ecologists, geographers, and resource managers because it's special policy and spatiotemporal dynamic complexity. This study explore the combined application of remote sensing, geographical information system and SLEUTH urban growth model to analyze and model urban growth pattern in Shenyang-Fushun metropolitan area northeastern China. The sequential RS images can give quantitative descriptors of the geometry of urban form to be computed and compared over time. The investigation is based on a 16-year time series data set compiled from interpreted historical TM satellite imagery. The SLEUTH model was calibrated using the mutil-temporal data set for the 6391.12km2 area where has experienced rapid urbanization in recent years. The model allowed a spatial forecast of urban growth, and future growth was projected out to 2050 assuming four different policy scenarios: (1) current trends (CT), (2) accelerated urban development (AUD), (3) protected urban development (PUD), and (4) limitative urban growth (LUD). The predicted urban growth shows similar compact pattern under each scenario except the current trends scenario that shows diffused urban growth pattern and most diffused growth appears at south of region. Edge growth and road gravity growth are the main growth types in the future. The accelerated urban development scenario shows the most urban growth area. The limitative urban growth scenario shows the least urban growth area. The protected urban development scenario shows moderate urban growth area and good protection to other land resources. The urban land of two mega cities will connect firstly to a whole on the south bank of Hun River about in 2040 in the accelerated urban development and the current trends scenarios, and will not connect on the other two scenarios until 2050. The combined method using remote sensing, geographical information system and SLEUTH urban growth model is powerful for representation, modeling and prediction of the spatiotemporal urban growth, and useful for understanding the alternative future planning scenarios, but location accuracy and scenarios design must be further considered for local application.