Footprint Method Research Articles

AOI-shapes: An Efficient Footprint Algorithm to Support Visualization of User-defined Urban Areas of Interest

Understanding urban areas of interest (AOIs) is essential in many real-life scenarios, and such AOIs can be computed based on the geographic points that satisfy user queries. In this article, we study the problem of efficient and effective visualization of user-defined urban AOIs in an interactive manner. In particular, we first define the problem of user-defined AOI visualization based on a real estate data visualization scenario, and we illustrate why a novel footprint method is needed to support the visualization. After extensively reviewing existing “footprint” methods, we propose a parameter-free footprint method, named AOI-shapes, to capture the boundary information of a user-defined urban AOI. Next, to allow interactive query refinements by the user, we propose two efficient and scalable algorithms to incrementally generate urban AOIs by reusing existing visualization results. Finally, we conduct extensive experiments with both synthetic and real-world datasets to demonstrate the quality and efficiency of the proposed methods.

Quantitative assessment of environmental impacts at the urban scale: the ecological footprint of a university campus

This paper explores the consumption-based ecological footprint method and its application aiming at a quantitative assessment of the sustainability of a university campus. The goal is to inform the planning decision-making process and evaluate the socio-technical solutions implemented in local urban settings for reducing energy consumption, decreasing environmental impacts and improving the quality of life of the campus' inhabitants. The case study taken for the analysis is the Politecnico di Torino, a Higher Education Institution (HEI) located in Northern Italy counting around 33,000 enrolled students in 2016. Data were collected from departments and administrative units of the Politecnico di Torino to identify the pressure exerted by the campus activities on the ecosystem during a reference year (2016). The study identified six main categories of consumption that were associated with their ecological footprint, i.e. the amount of land needed to produce the required resources and to absorb the generated waste, including CO2 emissions. Total footprint resulted in 6,200 gha: about half of the total city area, meaning that the campus would need a 310 times larger area to be self-sufficient. Normalizing this result with the number of students yields 0.19 gha/student. Transports had the highest share, with 49.4% out of the total campus impact, whereas energy covered 40.1%. Food, waste, land use and water counted, respectively, for 5.7%, 3.7%, 0.7% and 0.5%. This study presents the most comprehensive analysis to date of the environmental impact associated with an Italian HEI. This methodology and its implementation for the specific case of HEIs contribute to gain a better understanding of the overall impact of a university campus, as well as to create thresholds for comparative analysis, decision-making tools and policymaking to reduce the ecological footprint of the educational sector.

Progress in Life Cycle Impact Assessment: Water Vapor Emissions and Respiratory Inorganics

Life cycle assessment (LCA) is being included formally in EcoDesign regulations. Especially product carbon footprint will be mandatory in Europe. However, life cycle impact assessment, including global warming potential (GWP) in LCA, is hampered by several challenges. One of these is a lack of water vapor characterization indexes for GWP. A life cycle inventory profile for air transport fuel, including water vapor emissions, is evaluated with state-of-the-art practice, i.e., Environmental Footprint (EF) Method and International Life Cycle Data (ILCD) 2011 Mid-point+, neglecting water vapor’s high altitude GWP compared to carbon dioxide. Then, the characterization factor in GWP over 100 years (GWP100) for water vapor and alternate normalization for particulates are introduced. The results are compared. The main findings are that the previous EF method and ILCD both generate rather realistic results for Particulate Matter and Respiratory Inorganics mid-point indicators, respectively, but the number of premature deaths should be better allocated to different specific emissions, and that water vapor may dominate the GWP100 result over the usual carbon dioxide. Respiratory inorganics may need one impact category, each starting with particles smaller than 2.5 µm. LCIA mid-points need measurable and understandable bases. The common knowledge of water vapor’s GWP100 should not be neglected in LCIA for air transport and beyond where relevant.

Combination of product environmental footprint method and eco-design process according to ISO 14006: The case of an Italian vinery

To support the sustainable development of the primary sector, in line with green new deals emerging worldwide, eco-design of new agri-food products is a priority. The wine industry, due to its growing market, has matured the need to develop an approach for understanding the environmental impacts of its products and to develop strategies to reduce such impacts in a life cycle perspective. This study has a two-fold aim: presenting the development of a methodological proposal for the use of PEF and PEF-CR in the eco-design of wine products; testing its applicability in a case study in the wine sector. The methodological proposal considered the combination of ISO 14006 and PEF methods into a procedure consisting of 8 steps. The proposal was successfully applied in the case of an Italian vinery committed to develop a new red wine product with improved performance if compared to its standard red wine production. The study occurred between 2018 and 2020, collecting primary data related to vineyards and vinery operations. Results proved that PEF method and PEF-CR can be effectively used in the eco-design of new wine products with reduced environmental impacts. Moreover, the study confirmed that PEF method can be used within the framework of ISO 14006. The study on standard red wine production confirmed that the fuel and pesticide consumption in the vineyard operation are environmental hotspots. To reduce these impacts, a new selection of Merlot Khorus grapes was made by the Italian vinery. Results of the eco-designed proved that the new product scored a reduction in the potential environmental impacts.

High-throughput dilution-based growth method enables time-resolved exo-metabolomics of Pseudomonas putida and Pseudomonas aeruginosa.

SummaryUnderstanding metabolism is fundamental to access and harness bacterial physiology. In most bacteria, nutrient utilization is hierarchically optimized according to their energetic potential and their availability in the environment to maximise growth rates. Low‐throughput methods have been largely used to characterize bacterial metabolic profiles. However, in‐depth analysis of large collections of strains across several conditions is challenging since high‐throughput approaches are still limited – especially for non‐traditional hosts. Here, we developed a high‐throughput dilution‐resolved cultivation method for metabolic footprinting of Pseudomonas putida and Pseudomonas aeruginosa. This method was benchmarked against a conventional low‐throughput time‐resolved cultivation approach using either a synthetic culture medium (where a single carbon source is present) for P. putida or a complex nutrient mixture for P. aeruginosa. Dynamic metabolic footprinting, either by sugar quantification or by targeted exo‐metabolomic analyses, revealed overlaps between the bacterial metabolic profiles irrespective of the cultivation strategy, suggesting a certain level of robustness and flexibility of the high‐throughput dilution‐resolved method. Cultivation of P. putida in microtiter plates imposed a metabolic constraint, dependent on oxygen availability, which altered the pattern of secreted metabolites at the level of sugar oxidation. Deep‐well plates, however, constituted an optimal cultivation set‐up yielding consistent and comparable metabolic profiles across conditions and strains. Altogether, the results illustrate the usefulness of this technological advance for high‐throughput analyses of bacterial metabolism for both biotechnological applications and automation purposes.

Determining the Regional Carrying Capacity of the Wuhan City Circle Based on the Improved Ecological Footprint Method

AbstractThis study builds upon the traditional ecological footprint model by adding two new accounts of resource flows and using two new calculating method. This first account concerns water resources and accounts for water consumption in cities. The second account tracks basic types of pollutant accounts. Energy theory and net primary productivity were used to calculate the ecological footprint. Aiming at the problem of application in city, a city hectare spatial scale was used and a regional carrying capacity correction parameter was referenced. This framework provides insight into calculations of the bearing capacity of certain areas. The Wuhan City Circle was used as a case study with the objectives of calculating the ecological footprint and regional carrying capacity and analyzing its spatiotemporal evolution and capacity for sustainable development. The results indicated that from 2000 to 2015, the average annual rate of decline of the carrying capacity of the Wuhan City Circle was 9.18%, and from 2015 to 2017, the average annual rate of increase was 38.91%. The ecological footprints of fossil energy and build‐up land accounts increased over the years, exposing problems with land and energy utilization in the Wuhan City Circle. The continuous decline of the water resources carrying capacity reminds policy makers to pay attention to the protection of water areas. These results can help policy makers integrate historical data to adjust existing plans and make more specific future plans.

An Analysis of Arches of Foot: A Comparison between Ink Foot Print Method and Custom Made Podoscope Device Method

The present study aimed to assess the validity of the podoscopic images compared with ink footprint methods (comparing the two different methods using the same parameters). Objective: The evaluation of the reliability and accuracy of arch angle (AA) is the purpose of this paper's study. It includes Chippaux-Smirak Index (CSI), Staheli Index (SI), and Arch Index (AI) by comparing footprints obtained from ink footprint and custom-made podoscopic footprints. Methods: Measurements of AA, CSI, SI, and AI are obtained from ink footprints and custom-made podoscope among 416 healthy participants (aged 21 to 65). Accuracy and reliability were calculated for all the footprint indices obtained using the two methods. Minimal detectable change and the Standard error (SE) of measurement were also calculated. Results: SPSS Statistical software (version 20) at 95% confidence interval was used to execute and observe the statistical analysis. Descriptive analysis was used to calculate the Mean and standard deviations (SD). The intrarater reliability of ink footprints and podoscopic footprints were analyzed using Intraclass correlation (IC) executed at 95% confidence intervals (CIs). Reliability of the podoscopic method was interpreted when the values (≥0.75) as excellent, (0.4-0.74) as moderate, and (0-0.39) as poor. Our study reported that AA, CSI, SI, and AI obtained from the ink footprints and podoscope had high intrarater reliability and reproducible. The podoscope was designed in a lightweight manner for transportation purposes and utilized in under-served and rural areas. This custom-made device may be utilized in orthopedics, and it can also be used to collect data and for diagnostic purposes.

Assessing the environmental impact of China's tourism activities: a tourism heat footprint method.

Numerous research studies have examined carbon emissions generated from tourism activities. However, the environmental impact of anthropogenic heat release has not attracted researchers' attention. We apply the tourism heat footprint method to assess the environmental impact of China's tourism activities. The results indicate that (1) China's tourism heat footprint increased from 0.99 × 103 w/km2 in 1994 to 7.53 × 103 w/km2 in 2018, with an average annual growth rate of 8.82%. (2) Particularly during high seasons, the tourism heat footprint increases sharply; tourism transportation accounts for the highest proportion of the tourism heat footprint, ranging from 36.50 to 69.07% from 1994 to 2018. (3) The rapid growth in arrivals and transportation-related changes have contributed to the rapid growth of the tourism heat footprint. Advances in science and technology, laws and regulations, environmental pollution constraints, and national macroeconomic policy have helped reduce the tourism heat footprint. Generally, tourism activities caused by a significant increase in income are the root cause of tourism heat footprint growth. (4) Finally, some suggestions, including cultivating a low-energy tourism culture, improving energy efficiency, implementing low-energy policies, and performing spatial-temporal monitoring, are proposed. This paper expands sustainable tourism's analytical research and enriches the tourism footprint family evaluation process.

Mapping and Evaluating Human Pressure Changes in the Qilian Mountains

Human activities have dramatically changed ecosystems. As an irreplaceable ecological barrier in western China, the Qilian Mountains (QLM) provide various ecosystem services for humans. To evaluate the changes in the intensity of human activities in the QLM and their impact on the ecosystem, the human footprint (HF) method was used to conduct a spatial dataset of human activity intensity. In our study, the NDVI was used to characterize the growth of vegetation, and six categories of human pressures were employed to create the HF map in the QLM for 2000–2015 at a 1-km scale. The results showed that the mean NDVI during the growing season showed a significant increasing trend over the entire QLM in the period 2000–2015, while the NDVI showed a significant declining trend of more than 70% concentrated in Qinghai. Human pressure throughout the QLM occurred at a low level during 2000–2015, being greater in the eastern region than the western region, while the Qinghai area had greater human pressure than the Gansu area. Due to the improvement in traffic facilities, tourism, overgrazing, and other illegal activities, grasslands, shrublands, forests, wetlands, and bare land were the vegetation types most affected by human activities (in decreasing order). As the core area of the QLM, the Qilian Mountains National Nature Reserve (NR) has effectively reduced the impact of human activities. However, due to the existence of many ecological historical debts caused by unreasonable management in the past, the national park established in 2017 is facing great challenges to achieve its goals. These data and results will provide reference and guidance for future protection and restoration of the QLM ecosystem.

Evaluation of Carrying Capacity on Water Resources Based on Improved Water Footprint Method

A water footprint based principal component analysis method (WFPCA) has been proposed for evaluation of carrying capacity on water resources. The evaluation indexes can be defined based on the water footprint theory. Then the comprehensive evaluation value of water resources carrying capacity can be generated by the method of principal component analysis. The developed WFPCA method has been applied in the case study in Tongliao City, China. The results show that the indexes defined based on the water footprint theory can reflect the interactions between human being activities and water resources systems. The readjustment of water utilization structure affects the practical water use and the virtual water footprint in Tongliao City. The comparison of comprehensive evaluation values from 2010 to 2019 indicates that the water resources carrying capacity in Tongliao City continues to increase, which is benefited from the reasonable planning of water resources systems and the effective management of environment systems.

Evaluation of the influence on water consumption and water scarcity of different healthy diet scenarios

A deep understanding of the water-food nexus it is of a paramount importance as an avenue for sustainable development. Water forms the foundation for food production and a sustainable use of this resource is essential to guarantee the long-term productivity and to build resilient capacity in food and agricultural systems. Here we present methodological challenges regarding different water footprint (WF) methods applied to different dietary scenarios. The volumetric WF of three theoretical but realistic dietary patterns has been quantified (Omnivorous(O), Vegetarian(V) and Vegan(VG)), by means of the Water Footprint Network methodology. Moreover, the AWARE methodology is applied to assess potential impacts of water use trough the Water Scarcity Footprint (WSF). Diets are set to integrate and consider different drivers for food consumption encompassing the social value of the Mediterranean diet, healthy diet recommendations, food preferences of Italian consumers and the trade dimension of foodstuffs. In terms of volumetric WF, the O diet is the most water intensive one accounting for 2800 L/capita/day. A shift from an O to a V and VG diets allows to reduce the volumetric WF respectively 10% and 14%. Green water consumption accounts for the largest share (85%) in all three scenarios. Considering the WSF, V healthy diet is similar to the VG resulting in 11,069 and 11,130 L H2Oeq/capita/day respectively, whereas the O diet resulted in 11,932 L H2Oeq/capita/day. A sensitivity analysis was performed by changing each food category, one at a time, to its maximum and minimum value, in order to evaluate the significance of changes in the volumetric WF and WSF as well as the variables that mostly contribute to them. Results show that the volumetric WF associated with V and VG diets consumption overlay the O diet in respectively 53.5% and 35.7% of runs, while overlapping is improved comparing WSFs results. In this case, the WSFs of V and VG diets overlay the O diet in 83.5% of runs, suggesting that the alternative dietary scenarios would have little effect on the overall WSF and that the results are particularly sensitive to the different countries of importation. Results demonstrate the need to consider both volumetric WF and WSF with particular attention to trade analysis in order to support the development of new policies with the aim to foster sustainable consumption patterns, while preserving water resources.

LCA of an industrial luminaire using product environmental footprint method

This paper presents a life cycle assessment (LCA) for the industrial Light Emitting Diode (LED) luminaire by using Product Environmental Footprint (PEF) methodology. The assessment is carried out for raw material, assembly, distribution, use and end of life (EoL) stages, and all upstream emissions are considered. The analysis results show that the electricity consumption in use stage is the significant contributor for the overall impacts. Environmental benefits are identified from the EoL scenario analysis due to the adopted WEEE treatments. Electricity mix for the UK and other European countries are modelled for the comparison study that shows the use of renewable resources for electricity generation has lower overall impacts from the PEF view, but the impact towards land use that is caused by using biomass energy source for electricity production is noticeable, which is barely mentioned in the existing LCA studies. This research has made the following original contributions: 1) it is the first study examining the LED luminaire environmental performance by using the PEF methodology; 2) the electricity mix modelling for the European countries in the comparison study reveals the possible trade-off between using renewable/non-renewable resources for the electricity generation, which would be beneficial for further policy development for lighting and energy sectors; 3) the availability demonstration of the current PEF database for luminaires, and the reported analysis results would assist future similar LCA studies.

China’s Tea Industry: Net Greenhouse Gas Emissions and Mitigation Potential

Tea is an important cash crop and a beverage that is widely consumed across the world. In China (the largest producer of tea), the industry is growing, and there is a need to understand current greenhouse gas (GHG) emissions and sequestrations and the potential for mitigation so that climate action can be strategically undertaken. Life cycle assessment and carbon footprint methods were used to quantify emissions in tea cultivation and processing in the 16 major producing regions for the year 2017. The system boundary was from cradle to factory gate, which was divided into three subsystems, namely agricultural materials production, tea production and tea processing. Several units of analysis were chosen: the production region (province), the production area (ha) and the product (kg loose tea), etc. Total GHG emissions were 28.75 Mt CO2eq, which were mainly attributable to energy use in tea processing (41%), fertilizer production (31.6%) and soil emissions (26.7%). This equated to 12.0 t CO2eq per ha and 10.8 kg CO2eq per kg processed tea. Production in Hubei, Yunan, Guizhou, Sichuan and Fujian provinces contributed almost two thirds of industry emissions, representing priority areas for strategic action to reduce GHG emissions. At the same time, the total carbon sink amounted to 21.37 MtCO2, representing 74.3% of total GHG emissions. The proportions stored in soil, biomass, and tea production were 49.3%, 30.0%, and 20.7%, respectively. If best recommended management practices for fertilizer application were adopted and biomass was used as a source of energy for tea processing, the GHG emissions reduction potential was 16.66 Mt CO2eq, or 58% of total emissions. The GHG emissions associated with tea production and processing in China appeared high by comparison to other regions of the world. However, considering the carbon sink and emissions reduction potential, the tea industry should be viewed as an important sector for climate action. Moreover, the potential for substantial GHG emissions reduction through the adoption of improved practices seems very realistic. There may also be additional opportunities for GHG emissions reduction through the development of organic tea cultivation systems.

Assessing local impacts of water use on human health: evaluation of water footprint models in the Province Punjab, Pakistan

PurposeThe water footprint (WF) method is widely applied to quantify water use along the life cycle of products and organizations and to evaluate the resulting impacts on human health. This study analyzes the cause-effect chains for the human health damage related to the water use on a local scale in the Province Punjab of Pakistan, evaluates their consistency with existing WF models, and provides recommendations for future model development.MethodLocally occurring cause-effect chains are analyzed based on site observations in Punjab and a literature review. Then, existing WF models are compared to the findings in the study area including their comprehensiveness (covered cause-effect chains), relevance (contribution of the modeled cause-effect chain to the total health damage), and representativeness (correspondence with the local cause-effect chain). Finally, recommendations for the development of new characterization models describing the local cause-effect chains are provided.Results and discussionThe cause-effect chains for the agricultural water deprivation include malnutrition due to reduced food availability and income loss as well as diseases resulting from the use of wastewater for irrigation, out of which only the first one is addressed by existing WF models. The cause-effect chain for the infectious diseases due to domestic water deprivation is associated primarily with the absence of water supply systems, while the linkage to the water consumption of a product system was not identified. The cause-effect chains related to the water pollution include the exposure via agricultural products, fish, and drinking water, all of which are reflected in existing impact assessment models. Including the groundwater compartment may increase the relevance of the model for the study area.ConclusionsMost cause-effect chains identified on the local scale are consistent with existing WF models. Modeling currently missing cause-effect chains for the impacts related to the income loss and wastewater usage for irrigation can enhance the assessment of the human health damage in water footprinting.

Bio-Based Polyester Fiber Substitutes: From GWP to a More Comprehensive Environmental Analysis

The textile industry has lately started exploring the possibility of bio-sourcing for synthetics, notably polyester fiber, in the effort to break from the proven fossil-fuel dependency and decrease the environmental impacts. Traditionally made out of fossil-based polyethylene terephthalate polymer, polyester can be functionally substituted with three bio-based alternatives: bio-polyester, polytrimethylene terephthalate, and polylactic acid fibers. At present, however, there is a lack of studies on the environmental effects of such substitution. We, therefore, performed a comparative, cradle-to-gate life cycle assessment of conventional polyester and those substitutes featuring varying levels of bio-content. The impact assessment was performed with the most recent version of the Environmental Footprint method including some adaptations—using carbon crediting and a different, distance-to-target weighting approach. Bio-sourced fibers are found to cause higher environmental burdens than polyester. Acidification, eutrophication, ecotoxicity, water, and land use increase with the bio-content and are predominantly linked to the first generation feedstock (agriculture and transport). The results on climate change vary with the impact method adaptations, yet do not manage to offset the aforementioned deteriorations. In single scores, only three out of nine substitutes are found to perform comparably, while the rest perform significantly worse than the incumbent fiber.

Urban ecological security dynamic analysis based on an innovative emergy ecological footprint method

In China, with the rapid development of economy and the advancement of urbanization, the deterioration of urban ecological environment is obvious. In order to obtain the quantitative state of urban ecological security, this paper contributes an integrated and coupled emergy ecological footprint framework and Beijing city was selected to verify methodology effect in this paper. The results demonstrate that: (1) from 2010 to 2019, the change range of EEFB is from 6.37 to 9.29%; meanwhile, EEFI is from 7.95 to 17.72%; EEFE is from 36.36 to 63.71%; EEFP is from 18.45% to 41.65%. Comparing the proportions of four subparts, the energy resource products (EEFE) and emissions (EEFP) are the main factors, far more significant than biological resources (EEFB) and industrial products (EEFI). (2) Compared to all ECCS data, there is a definite growing trend in Beijing city, from 2.68E + 4 hm2/cap in 2010 to 4.72E+4 hm2/cap in 2019, approximately 42.22% growth range. (3) Four sustainable indicators analysis: The changes of EEFT, EBI, and EEF are from 3.1, 2.46, and 1.02 in 2010 to 0.688, 9.29 and 1.14 in 2019, respectively. For EDI, total proportions of fossil land and built-up land are 85.25% to 90.43% of the entire EEF in Beijing city. These results reflect that Beijing city is suffering from a substantial ecological challenge due to remarkable ecological deficit, awfully high emergy ecological footprint intensity, and low cooperation level between ecological system and economic system. To identify key improvement factors, Pearson correlation analysis was conducted in this paper and revealed the most positive and negative elements, which are the unbalanced industrial structure and a large proportion heavy and polluting industries in Beijing city. Finally, based on the pivotal influencing factors, corresponding strategies and measures are proposed to improve and optimize the ecological security in Beijing city.

Comparative life cycle assessment of polymeric membranes: Polyacrylonitrile, polyvinylimidazole and poly (acrylonitrile-co-vinylimidazole) applied for CO2 sequestration

The life cycle assessment analysis of polymeric membranes, namely polyacrylonitrile (PAN), polyvinylimidazole (PVIM), and copolymer P(AN-co-VIM): 50:50 ratio utilized for CO2 sequestration is presented in this work for the first time. The Center of Environmental Science (CML) baseline 2000, cumulative energy demand, ecological footprint, and greenhouse gas protocol methods were applied to attain comprehensive information regarding the originated environmental burdens from the synthesis of the membrane. The PVIM membrane manifested the minimum environmental impacts, comparatively. The global warming, marine ecotoxicity, and human toxicity categories belonged to the P(AN-co-VIM) as the polymeric membrane with the highest environmental impact were accounted for 1.20, 1.36, and 1.18, greater than PVIM, respectively. These impacts were augmented in the range of 16.88%–27.59% for P(AN-co-VIM), predominantly derived from dimethylformamide (DMF) consumption and electricity demand. The P(AN-co-VIM) energy usage was 3799 MJ with a 92% contribution of fossil fuels, 1.2 times more than the PVIM. The CO2 emission (kg CO2 eq) from fossil fuels was as follows: P(AN-co-VIM) (146.2) > PAN (123.3) > PVIM (121.8). Besides, the sensitivity of PAN, PVIM, and P(AN-co-VIM) regarded a ±20% fluctuation in the DMF was estimated as 14.41–17.71%, 13.45–19.08%,​ and 11.08–16.78% for PAN, PVIM, and P(AN-co-VIM), respectively. Accordingly, the PVIM was recognized as the membrane with the highest environmental compatibility.

Investigating historical dynamics and mitigation scenarios of anthropogenic greenhouse gas emissions from pig production system in China

This study introduced a carbon footprint (CF) method based on a life cycle assessment to analyze greenhouse gas (GHG) emissions derived from pig production system in China by using national statistical data during 2000–2016. Results showed that the CF of pig production in China was showing a reduction trend. Specifically, the average CFs of unit mass alive pig in the backyard, specialized, medium-scale and large-scale farms in China were 1.78 kg CO2-eq/kg, 1.55 kg CO2-eq/kg, 1.65 kg CO2-eq/kg and 1.65 kg CO2-eq/kg, respectively, during 2000–2016. Therein, the feedstuffs production and manure management are the main GHG sources in pig production system in China. The total GHG emissions of the Chinese pig system were slightly decreasing from 128.37 million tons (Mt) CO2-eq in 2000 to 127.08 Mt CO2-eq in 2016, while the pig production quantity was increased by 35.12% during the study period. It implied that the pig production system in China had developed toward a positive effect on GHG emissions reduction in recent years. Moreover, this study also estimates the possible quantity of GHG emissions of Chinese pig sector in 2030 through scenario analysis. The simulated results were ranging from 18.48 to 176.42 Mt CO2-eq/yr, reflecting that the Chinese pig sector still had considerable mitigation potential for GHG emissions. The shift towards intensive pig production, improved feed crop cultivation and manure management systems would be the key points to reduce the GHG emissions of pig production system. This study would contribute to the development of the pig production system in China with a cleaner production approach.

An Efficient Multi-stage Object-Based Classification to Extract Urban Building Footprints from HR Satellite Images

Urban building information can be effectively extracted by applying object-based image segmentation and multi-stage thresholding on High Resolution (HR) remote sensing satellite imageries. This study provides the results obtained using this method on the images of Indian remote sensing satellite, CARTOSAT-2S launched by the Indian Space Research Organization (ISRO). In this study, a method is developed to extract urban building footprints from the HR remote sensing satellite images. The first step of the process consists of generating highly dense per pixel Digital Surface Model (DSM) by using semi global matching algorithm on HR satellite stereo images and applying robust ground filtering to generate Digital Terrain Model (DTM). In the second step, multi-stage object-based approach is adopted to extract building bases using the PAN sharpened image, normalized Digital Surface Model (nDSM) derived from DSM and DTM, and Normalised Difference Vegetation Index (NDVI). The results are compared with the manual method of drawing building footprints by cartographers. An average precision of 0.930, recall of 0.917, and f-score of 0.922 are obtained. The results are found to be in a match with the method using the high resolution Airborne LiDAR DSM by providing a solution for large areas, low cost and low time.

Spatiotemporal variations of agricultural water footprint and socioeconomic matching evaluation from the perspective of ecological function zone

The water footprint theory has provided an effective approach for evaluating the utilization of freshwater resources in agricultural production. However, there are few studies have explored the dynamic coupling relationship between water footprint and socioeconomic factors, especially from the perspective of regional ecological features. Therefore, the water footprint method was used to investigate the dynamic evolution of agricultural water consumption from 2005 to 2015 in Zhangjiakou, an extremely water-scarce city which is divided into six ecological zones (I, II, III, IV, V, and VI). Then mathematical models such as the Gini coefficient were first employed to evaluate the spatiotemporal matching characteristics of agricultural water footprint and socioeconomic factors. The results show that: (1) The agricultural water footprint increased by 1.69 × 109 m3 in Zhangjiakou, of which the animal products water footprint increased by 1.59 × 109 m3, accounting for 94%. (2) Cereals had always been the major contributors to crop water footprint, with an increasing contribution rate from 49% to 54%. Milk and egg products were the main drivers for the increasing water footprint of animal products, with a total contribution rate increased from 46% to 55%. Meanwhile, the spatial differentiation was significant. The contribution rate of the cereal water footprint was less than 50% in counties of high-altitude ecological zones I, II and IV in 2015, while it was higher than 50% in counties of low-altitude ecological zones III, V and VI. (3) The per unit area water footprint in counties of the ecological zone III was much higher than the average level, while per capita water footprint and per unit output value water footprint were far below it, indicating agricultural structure optimization requires a comprehensive consideration of multiple socioeconomic factors. This study is expected to provide policy-makers with scientific guidance that is conducive to agricultural water conservation and ecological zone planning.