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Erratum to:First Record of Middle Eocene Elephant Ancestors'Footprints in the Gonjo Basin,East Xizang Plateau
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作者 Asma Tahir Huazhou Yao +4 位作者 Junaid Khan Yangui Li He Zhao Yue Yu Tang Yuan 《Journal of Earth Science》 2025年第4期1877-1877,共1页
Erratumto:Journal of Earth Science https://doi.org/10.1007/s12583-023-1946-6 The original version of this article unfortunately contained three mistakes.1.The presentation of Equation(4)was incorrect.The corrected one... Erratumto:Journal of Earth Science https://doi.org/10.1007/s12583-023-1946-6 The original version of this article unfortunately contained three mistakes.1.The presentation of Equation(4)was incorrect.The corrected one is given below. 展开更多
关键词 Middle Eocene Elephant ancestors footprints Gonjo Basin East Xizang
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Associations between individuals’daily carbon footprints and exposures to air pollution,noise,and greenspace in space and time
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作者 Jianwei Huang Mei-Po Kwan 《Geography and Sustainability》 2025年第3期197-208,共12页
To mitigate the catastrophic impacts of climate change,many measures and strategies have been designed and implemented to encourage people to change their daily behaviors for a low-carbon society transition.However,mo... To mitigate the catastrophic impacts of climate change,many measures and strategies have been designed and implemented to encourage people to change their daily behaviors for a low-carbon society transition.However,most people generate carbon emissions through their daily activities in space and time.They are also exposed to multiple environmental factors(e.g.,air pollution,noise,and greenspace).Changing people’s behaviors to reduce carbon emissions can also influence their multiple environmental exposures and further influence their health outcomes.Thus,this study seeks to examine the associations between individuals’daily carbon footprints and their exposures to multiple environmental factors(i.e.,air pollution,noise,and greenspace)across different spa-tial and temporal contexts using individual-level data collected by portable real-time sensors,an activity-travel diary,and a questionnaire from four communities in Hong Kong.The results first indicated that individuals’car-bon footprints of daily activities varied across different spatial and temporal contexts,with home and nighttime having the highest estimated carbon footprints.We also found that activity carbon footprints have a positive asso-ciation with PM2.5,which is particularly strong at home and from morning to nighttime,and mixed associations with noise(positive at home and nighttime,while negative in other places and during travel,from morning to afternoon).Besides,carbon footprints also have consistent negative associations with shrubland and woodland across different spatial and temporal contexts.The findings can provide essential insights into effective measures for promoting the transition to a low-carbon society. 展开更多
关键词 Activity carbon footprints Individual-level data Portable real-time sensors Multiple environmental exposures Low-carbon society transition
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Greenhouse Gas Footprints of Maize Cultivation Systems in Different Climate Zones:Field Data Validation and Application of CNMM–DNDC as a Hydro-Biogeochemical Model
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作者 Siqi LI Wei ZHANG +12 位作者 Yong LI Chunyan LIU Bo ZHU Job KIHARA Peter BOLO Zhisheng YAO Kai WANG Shenghui HAN Rui WANG Jiarui SUN Klaus BUTTERBACH-BAHL Min ZHOU Xunhua ZHENG 《Advances in Atmospheric Sciences》 2025年第11期2365-2393,共29页
Accurate quantification of life-cycle greenhouse gas(GHG)footprints(GHG_(fp))for a crop cultivation system is urgently needed to address the conflict between food security and global warming mitigation.In this study,t... Accurate quantification of life-cycle greenhouse gas(GHG)footprints(GHG_(fp))for a crop cultivation system is urgently needed to address the conflict between food security and global warming mitigation.In this study,the hydrobiogeochemical model,CNMM-DNDC,was validated with in situ observations from maize-based cultivation systems at the sites of Yongji(YJ,China),Yanting(YT,China),and Madeya(MA,Kenya),subject to temperate,subtropical,and tropical climates,respectively,and updated to enable life-cycle GHG_(fp)estimation.The model validation provided satisfactory simulations on multiple soil variables,crop growth,and emissions of GHGs and reactive nitrogen gases.The locally conventional management practices resulted in GHG_(fp)values of 0.35(0.09–0.53 at the 95%confidence interval),0.21(0.01–0.73),0.46(0.27–0.60),and 0.54(0.21–0.77)kg CO_(2)e kg~(-1)d.m.(d.m.for dry matter in short)for maize–wheat rotation at YJ and YT,and for maize–maize and maize–Tephrosia rotations at MA,respectively.YT's smallest GHG_(fp)was attributed to its lower off-farm GHG emissions than YJ,though the soil organic carbon(SOC)storage and maize yield were slightly lower than those of YJ.MA's highest SOC loss and low yield in shifting cultivation for maize–Tephrosia rotation contributed to its highest GHG_(fp).Management practices of maize cultivation at these sites could be optimized by combination of synthetic and organic fertilizer(s)while incorporating 50%–100%crop residues.Further evaluation of the updated CNMM-DNDC is needed for different crops at site and regional scales to confirm its worldwide applicability in quantifying GHG_(fp)and optimizing management practices for achieving multiple sustainability goals. 展开更多
关键词 GHG footprint carbon footprint TROPICAL SUBTROPICAL warm temperate process model
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The calculation and analysis of ecological footprints,diversity and developm ent capacity of China 被引量:15
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作者 XUZhongmin CHENGGuodong +2 位作者 ZHANGZhiqiang PaulHTemplet YongyuanYIN 《Journal of Geographical Sciences》 SCIE CSCD 2003年第1期19-26,共8页
T he ecological footprint of China's provinces is calculated in this pap er. In general, China's development is not sustainable because its ecological footprint is beyond its bio-capacity. The sustainability s... T he ecological footprint of China's provinces is calculated in this pap er. In general, China's development is not sustainable because its ecological footprint is beyond its bio-capacity. The sustainability status of each pr ovince in China is presented. Ulanowicz's development capacity formula w as introduced to discuss the relationship of development and ecological footprin t's diversity. The diversity of ecological impacts is related to the e fficiency with which an economy uses the source and sink services of the environment and, in this view, should be a factor in economic output. Developme nt capacity, calculated from the ecological footprint and its diversity , is used to examine the relationship of economic output with the st ructure of the ecological footprint. China and its provinces are prese nted as a case study to investigate this relationship. The analysis s hows that footprint capacity is significant in predicting economic outp ut. Increasing the ecological footprint's diversity is presented as another way to increase development capacity. 展开更多
关键词 ecological footprints DIVERSITY development capacity China
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Research on Dinoasur Footprints in Zizhou, Shaanxi Province, China 被引量:3
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作者 WANG Baopeng LI Jianjun +5 位作者 BAI Zhiqiang GAO Junmin DONG Shurong HU Bailin ZHAO Suiqin CHANG Jieqiong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期1-18,共18页
In recent years, the discoveries of dinosaur footprints have been successively reported from Dianshi Town, Zizhou City, Shaanxi Province. The footprints include the tracks of theropod, ornithopod and sauropod as well.... In recent years, the discoveries of dinosaur footprints have been successively reported from Dianshi Town, Zizhou City, Shaanxi Province. The footprints include the tracks of theropod, ornithopod and sauropod as well. Actually, the dinosaur footprints were found by local inhabitants much earlier in history, but not for science. The slabs bearing the dinosaur footprints were collected for domestic use, such as building stones, millstones, cellar covers, sheepfold fences, windlass holders, etc. This paper is to describe the dinosaur footprints on both sides of three slabs used for cellar covers, sheepfold fences and windlass holders by the local people. 24 dinosaur footprints and 4 trackways have been recognized and all of them belong to theropod. Four kinds of dinosaur footprints are identified, including 1 new ichnogenus and 2 new ichnospecies: (1) Shanbeipus caudatus ichnogen, et ichnosp, nov.; (2) Pengxianpus yulinensis ichnosp, nov.; (3) Eubrontes ichnosp; (4) Kayentapus ichnosp. Dinosaur-footprint-bearing beds were initially identified as the Fuxian Formation of the Lower Jurassic. Multipal dinosaur footprints associated with fragment plant fossils suggest a humid fluviolacustrine environment setting in the Ordos Basin during the early period of the Jurassic. 展开更多
关键词 Zizhou dinosaur footprints early Jurassic Fuxian Formation
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Preventing the Immense Increase in the Life-Cycle Energy and Carbon Footprints of LLM-Powered Intelligent Chatbots 被引量:3
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作者 Peng Jiang Christian Sonne +2 位作者 Wangliang Li Fengqi You Siming You 《Engineering》 SCIE EI CAS CSCD 2024年第9期202-210,共9页
Intelligent chatbots powered by large language models(LLMs)have recently been sweeping the world,with potential for a wide variety of industrial applications.Global frontier technology companies are feverishly partici... Intelligent chatbots powered by large language models(LLMs)have recently been sweeping the world,with potential for a wide variety of industrial applications.Global frontier technology companies are feverishly participating in LLM-powered chatbot design and development,providing several alternatives beyond the famous ChatGPT.However,training,fine-tuning,and updating such intelligent chatbots consume substantial amounts of electricity,resulting in significant carbon emissions.The research and development of all intelligent LLMs and software,hardware manufacturing(e.g.,graphics processing units and supercomputers),related data/operations management,and material recycling supporting chatbot services are associated with carbon emissions to varying extents.Attention should therefore be paid to the entire life-cycle energy and carbon footprints of LLM-powered intelligent chatbots in both the present and future in order to mitigate their climate change impact.In this work,we clarify and highlight the energy consumption and carbon emission implications of eight main phases throughout the life cycle of the development of such intelligent chatbots.Based on a life-cycle and interaction analysis of these phases,we propose a system-level solution with three strategic pathways to optimize the management of this industry and mitigate the related footprints.While anticipating the enormous potential of this advanced technology and its products,we make an appeal for a rethinking of the mitigation pathways and strategies of the life-cycle energy usage and carbon emissions of the LLM-powered intelligent chatbot industry and a reshaping of their energy and environmental implications at this early stage of development. 展开更多
关键词 Large language models Intelligent chatbots Carbon emissions Energy and environmental footprints Life-cycle assessment Global cooperation
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First Record of Middle Eocene Elephant Ancestors’Footprints in the Gonjo Basin,East Tibet Plateau
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作者 Asma Tahir Huazhou Yao +4 位作者 Junaid Khan Yangui Li He Zhao Yue Yu Tang Yuan 《Journal of Earth Science》 SCIE CAS CSCD 2024年第4期1224-1235,共12页
It is the first time that the fossil footprints of a group of Middle Eocene elephant ancestors have been discovered in the Gonjo Basin,East Tibet Plateau.The Gonjo Formation is attributed to the Middle Eocene Epoch(U-... It is the first time that the fossil footprints of a group of Middle Eocene elephant ancestors have been discovered in the Gonjo Basin,East Tibet Plateau.The Gonjo Formation is attributed to the Middle Eocene Epoch(U-Pb age=44.7±1.2 Ma)and consists mainly of purplish-red,medium-to coarse-grained sandstones,siltstones interbedded with mudstones,and conglomerates with sedimentary structures like ripple marks,rip-up clasts,and trough-cross bedding,suggesting fluvial-lacustrine systems.The group of fossil footprints has a characteristic oval-concave shape,and the toe impressions are absent.Some fossil footprints are overstepped with a pockmarked texture resembling Proboscipeda enigmatica.More than 165 fossil footprints of the group are relatively well-preserved with different diameters,which is evidence of highly social behavior and trackmakers of different ages,including calves,juveniles,adolescents,and adults.The size frequency of the fossil footprints enabled us to deduce the body mass,shoulder height,and hip-height distribution of the trackmakers that crossed the East Tibet Plateau 44.7 Ma ago.The trackmakers comprised an estimated average hip-height of 111.8 cm,an average shoulder height of 172.8 cm for males/155.9 cm for females,and an average body mass of approximately 1218.1 kg for males/907.8 kg for females.The abundance of fossil footprints reveals that in the Middle Eocene Epoch,the environment was extraordinarily conducive for the elephant ancestors to live in the East Xizang region. 展开更多
关键词 Proboscipeda enigmatica East Tibet Plateau Gonjo Formation fossil footprints fluvial-lacustrine
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Discovery of the Middle Jurassic Small Theropod Footprints in Eastern Xizang,China
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作者 Yangui Li Huazhou Yao +7 位作者 Asma Tahir Junaid Khan William J.Foster Ping Wang Laishi Zhao Zhihui An Chuanshang Wang Jianxiong Wang 《Journal of Earth Science》 SCIE CAS CSCD 2024年第6期1820-1831,共12页
Jurassic continental strata are widely distributed in the Changdu area of eastern Xizang,but very few dinosaur footprints have been reported.Abundant sauropod,ornithopod and theropod footprints preserved in the Wenda ... Jurassic continental strata are widely distributed in the Changdu area of eastern Xizang,but very few dinosaur footprints have been reported.Abundant sauropod,ornithopod and theropod footprints preserved in the Wenda site have been found during the recent geological surveys.This is a novel assemblage of the Middle Jurassic dinosaur footprints.These footprint fossils provide a key insight into the members of dinosaur faunas,and the behavior of the trackmakers.Here,the newly discovery small theropod footprints,which are identified as Wildeichnus isp.,are discussed.The analysis of two trackways suggest that these two trackmakers(with a hip height of approx.35 cm,and a body length of approx.1 m)were moving slowly,with an estimated speed of 0.82 and 0.57 m/s,respectively.It is unusual for small theropods to move so slowly,and the present study supports the view that Wildeichnus had a global distribution,but the trackmaker of Wildeichnus is not interpreted as a juvenile Grallator. 展开更多
关键词 dinosaur footprints MORPHOLOGY Middle Jurassic Dabuka Formation Changdu area
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Dinosaur Footprints of Early Cretaceous in Site 1 ,Yanguoxia ,Yongjing Country ,Gansu Province
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《Journal of China University of Geosciences》 SCIE CSCD 2001年第2期6-,61,共2页
关键词 SITE Yongjing Country Gansu Province Yanguoxia Dinosaur footprints of Early Cretaceous in Site 1
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Re-examining Geos Neighbourhood for Its Energy Self-sustained Ability Through Ecological Footprints, Net Energy, and Life Cycle Assessment Tools
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作者 Mengxiang HU 《Agricultural Science & Technology》 CAS 2014年第8期1384-1389,共6页
There are mounting evidences that human consume significant quantities of resources and have a major impact on the environment. Some research indicates that since the 1980s human demands on the biosphere have exceeded... There are mounting evidences that human consume significant quantities of resources and have a major impact on the environment. Some research indicates that since the 1980s human demands on the biosphere have exceeded its regen-errative capacity. One way to solve this problem is to minimize the inappropriate ex-ploitation from environment. This essay wil focus on energy self-sustained project, which is a specific way to reduce energy requirements. Energy self-sustained project refers to that energy production is equal to the amount consumed. Three concepts are quoted in the fol-lowing to assess whether the project achieve zero-energy or not. First, ecological footprint, which provides an indication of the human load on the biosphere, is uti-lized to measure the inputs and outputs of the bioregion, which is also beneficial for defining the potential energy. Another one is life cycle assessment, which evaluates environmental load that relates to the entire life periodic system of a product, is helpful to measure the products used in the energy self sustained project. In addi-tion, net energy, and gross resource abundance, definitions for selection, or hierar-chy of different energy resources, can evaluate the new energy resources in project. Geos Neighbourhood, located in colorado, was planned as the largest net-zero energy neighbourhood in the United States. To meet the energy self sustainability, earth and sun power completely sustain the community's energy needs, and re-place al fossil fuels. Compared with the traditional communities, Geos Neighbour-hood minimize the adverse impact on the environment. As tools for assessment, ecological footprint, life circle assessment, and net energy, are al used to analyse the planning and design principles in the neighbourhood. By the research, the de-sign principles and energy use in Geos Neighbourhood wil be re-examined that whether the zero energy project achieves the reduction of ecological footprint, and energy self sustainability. In addition, life circle assessment wil re-examine the ma-terials used in the community also. Final y, the concept of 'net energy' wil test solar energy and earth power which is the major energy used in Geos Neighbour-hood. 展开更多
关键词 Energy self sustained Ecological footprints Net energy Life cycle assessment Geos Neiqhbourhood
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Footprints of China Auto International Exhibition Tour
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《China's Foreign Trade》 2008年第21期25-26,共2页
November 2008,the Sixth China Auto International(Algeria & Egypt)Exhibi- tion Tour is ready.Since the first session was held in 1995,the Chinese auto enterprises have been to Vietnam,Cambodia,Syria,and Russian.In ... November 2008,the Sixth China Auto International(Algeria & Egypt)Exhibi- tion Tour is ready.Since the first session was held in 1995,the Chinese auto enterprises have been to Vietnam,Cambodia,Syria,and Russian.In the past five sessions,Chinese auto brands not only experienced the endless hardships, 展开更多
关键词 AUTO footprints of China Auto International Exhibition Tour
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Review and Outlook of China Electronic and IT Industry Footprints in IEC International Standardization Activities
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作者 Hu Jingping 《China Standardization》 2006年第6期19-26,共8页
  Year 2006 is the year marking the 100th anniversary of the founding of International Electrotechnical Commission (IEC). IEC is mainly engaged in the international standardization for electrical and electronic tech...   Year 2006 is the year marking the 100th anniversary of the founding of International Electrotechnical Commission (IEC). IEC is mainly engaged in the international standardization for electrical and electronic technology field aiming at promoting international trade and technology cooperation and exchange, improving product and service quality, upgrading productivity and protecting the environment as well as human health and safety. Most countries worldwide adopt standards developed and promulgated by IEC, providing a platform to international trade and technical exchange. China has being a member since 1957. Electronic and IT are the most developed and energetic filed in recent decades. Number of IEC TC/SC specialized in electronic and IT amounts up to 52.…… 展开更多
关键词 IEC Review and Outlook of China Electronic and IT Industry footprints in IEC International Standardization Activities IT OUTLOOK
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A TRAIL-BLAZER'S FOOTPRINTS ——A biographic sketch of CAS member Li Yiyi
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作者 Wang Zuoming & Fan Guilan(Shenyang Institute of Metal Research, CAS) 《Bulletin of the Chinese Academy of Sciences》 1996年第3期274-277,共4页
People will never forget a scene at the First National Conference of Model Workers held in 1959,when the No.1 blast furnace of the No.1 Steelworks under the Benxi Iron & Steel Corporation was named a national stan... People will never forget a scene at the First National Conference of Model Workers held in 1959,when the No.1 blast furnace of the No.1 Steelworks under the Benxi Iron & Steel Corporation was named a national standard bearer of the Red Flag,with its productivity ratio having won the national championship.The story was reported by the People’s Daily,Soviet Women’s Journal and Benxi Daily.As the young leader of the cited team of furnacemen, Li Yiyi became known to all. Time flies by and 34 years have elapsed since then. 展开更多
关键词 Li A TRAIL-BLAZER’S footprints A biographic sketch of CAS member Li Yiyi CAS TRAIL
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Coupling analysis of social-economic water consumption and its effects on the arid environments in Xinjiang of China based on the water and ecological footprints 被引量:9
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作者 ZHANG Pei DENG Mingjiang +5 位作者 LONG Aihua DENG Xiaoya WANG Hao HAI Yang WANG Jie LIU Yundong 《Journal of Arid Land》 SCIE CSCD 2020年第1期73-89,共17页
In arid areas,ecological degradation aroused by over-exploitation of fresh water,expansion of artificial oasis and shrinkage of natural oasis,has drawn attention of many scholars and officials.The water and ecological... In arid areas,ecological degradation aroused by over-exploitation of fresh water,expansion of artificial oasis and shrinkage of natural oasis,has drawn attention of many scholars and officials.The water and ecological footprints can be used to quantitatively evaluate the water consumption of social-economic activities and their influence on the eco-environments.In addition,increase of the water footprint indicates the expansion of artificial oasis,and the influence on the natural oasis could be reflected by the variation of the ecological footprint.This study was conducted to answer a scientific question that what is the quantitative relationship between the expansion of the artificial oasis and the degradation of the natural oasis in the arid environments of Xinjiang,China.Thus,based on the social-economic data,water consumption data and meteorological data during 2001–2015,we calculated the water and ecological footprints to express the human-related pressure exerted on the water resources and arid environments in Xinjiang(including 14 prefectures and cities),and explore the relationship between the water and ecological footprints and its mechanism by using the coupling analysis and Granger causality test.The results show that both the water and ecological footprints of Xinjiang increased significantly during 2001–2015,and the increasing rate of the ecological footprint was much faster than that of the water footprint.The coupling degree between the water and ecological footprints was relatively high at the temporal scale and varied at the spatial scale.Among the 14 prefectures and cities examined in Xinjiang,the greater social-economic development(such as in Karamay and Urumqi)was associated with the lower coupling degree between the two footprints.Increases in the water footprint will cause the ecological footprint to increase,such that a 1-unit increase in the consumption of water resources would lead to 2–3 units of ecological degradation.The quantitative relationship between the increases of the water and ecological footprints,together with the intensities of water consumption both in the natural and artificial oases of Tarim River Basin,have approved the fact that the formation and expansion of 1 unit of the artificial oasis would bring about the degradation of 2 units of the natural oasis.These conclusions not only provide a technical basis for sustainable development in Xinjiang,but also offer a theoretical guide and scientific information that could be used in similar arid areas around the world. 展开更多
关键词 water consumption ecological footprint water footprint Granger causality test natural oasis artificial oasis Tarim River
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Carbon and Nitrogen Footprints of Major Cereal Crop Production in China:A Study Based on Farm Management Surveys 被引量:3
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作者 XU Chunchun CHEN Zhongdu +1 位作者 JI Long LU Jianfei 《Rice science》 SCIE CSCD 2022年第3期288-298,共11页
Greenhouse gas(GHG)emissions and reactive nitrogen(Nr)releases are central environmental problems,which are closely linked to climate change,environmental ecology and crop production.Sustainable development of agricul... Greenhouse gas(GHG)emissions and reactive nitrogen(Nr)releases are central environmental problems,which are closely linked to climate change,environmental ecology and crop production.Sustainable development of agriculture plays an important role in GHG emissions and Nr loss.The life cycle assessment(LCA)method was used to calculate the product and farm carbon footprints(CFs)and nitrogen footprints(NFs)in rice,wheat and maize production in China based on farm survey data.The results pinpointed that the CFs of rice,wheat and maize were 0.87,0.30 and 0.24 kg/kg.Meanwhile,the computed NFs were 17.11,14.26 and 6.83 g/kg,respectively.Synthetic nitrogen fertilizer applications and methane(CH4)emissions were dominant CF sources,while ammonia(NH3)volatilization was the main NF contributor.Moreover,significant decreases in CF and NF by 20%–54%and 33%–61%,respectively,were found in large-size farms(>20 hm^(2))when compared to small-size farms(<0.7 hm^(2)).Furthermore,the significantly positive relationships between CF and NF indicated the potential for simultaneous mitigation in the regions with high agricultural inputs,like amounts of fertilizer.Based on our results,some effective solutions would be favorable toward mitigating climate change and eutrophication of the major cereal crop production in China,especially optimizing fertilizer use and farm machinery operation efficiencies,as well as developing large-size farms with intensive farming. 展开更多
关键词 carbon footprint nitrogen footprint life cycle assessment grain crop sustainability
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Wide/narrow azimuth acquisition footprints and their effects on seismic imaging 被引量:3
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作者 Di Bangrang Xu Xiucang Wei Jianxin 《Petroleum Science》 SCIE CAS CSCD 2008年第4期308-313,共6页
Acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering.At present,the study on acquisition footpr... Acquisition footprint is a new concept to describe the seismic noise in three-dimensional seismic exploration and it is closely related to geometry and observation shuttering.At present,the study on acquisition footprints has become a hot spot.In partnership with the Dagang Oilfield,we used the channel sand body seismic physical model to study the characteristics of wide/narrow azimuth acquisition footprints and analyzed and compared the two types of footprints and their effects on target imaging.In addition,the footprints caused by data processing of the normal moveout offset(NMO)stretching aberration were discussed.These footprints are located only in the shallow or middle layer in the time slice,and possibly affect the imaging of shallow target layers,and have no influence on deep target imaging.Seismic physical modeling has its advantages in the study of acquisition footprints. 展开更多
关键词 Wide/narrow azimuth geometry acquisition footprint stretching aberration time slice seismic imaging
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An analysis of energy consumption and carbon footprints of cryptocurrencies and possible solutions 被引量:2
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作者 Varun Kohli Sombuddha Chakravarty +2 位作者 Vinay Chamola Kuldip Singh Sangwan Sherali Zeadally 《Digital Communications and Networks》 SCIE CSCD 2023年第1期79-89,共11页
There is an urgent need to control global warming caused by humans to achieve a sustainable future.CO_(2) levels are rising steadily,and while countries worldwide are actively moving toward the sustainability goals pr... There is an urgent need to control global warming caused by humans to achieve a sustainable future.CO_(2) levels are rising steadily,and while countries worldwide are actively moving toward the sustainability goals proposed during the Paris Agreement in 2015,we are still a long way to go from achieving a sustainable mode of global operation.The increased popularity of cryptocurrencies since the introduction of Bitcoin in 2009 has been accompanied by an increasing trend in greenhouse gas emissions and high electrical energy consumption.Popular energy tracking studies(e.g.,Digiconomist and the Cambridge Bitcoin Energy Consumption Index(CBECI))have estimated energy consumption ranges from 29.96 TWh to 135.12 TWh and 26.41 TWh to 176.98 TWh,respectively for Bitcoin as of July 2021,which are equivalent to the energy consumption of countries such as Sweden and Thailand.The latest estimate by Digiconomist on carbon footprints shows a 64.18 MtCO_(2) emission by Bitcoin as of July 2021,close to the emissions by Greece and Oman.This review compiles estimates made by various studies from 2018 to 2021.We compare the energy consumption and carbon footprints of these cryptocurrencies with countries around the world and centralized transaction methods such as Visa.We identify the problems associated with cryptocurrencies and propose solutions that can help reduce their energy consumption and carbon footprints.Finally,we present case studies on cryptocurrency networks,namely,Ethereum 2.0 and Pi Network,with a discussion on how they can solve some of the challenges we have identified. 展开更多
关键词 Blockchain Carbon footprint Climate change Cryptocurrency SUSTAINABILITY
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Effect of organic amendment amount on soil nematode community structure and metabolic footprints in soybean phase of a soybean-maize rotation on Mollisols 被引量:2
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作者 Fengjuan PAN Xiaozeng HAN +2 位作者 Na LI Jun YAN Yanli XU 《Pedosphere》 SCIE CAS CSCD 2020年第4期544-554,共11页
It has been well documented that organic amendment affects soil nematode community structure.However,little is known about the effect of organic amendment amount on soil nematodes.To assess the effect of the amount of... It has been well documented that organic amendment affects soil nematode community structure.However,little is known about the effect of organic amendment amount on soil nematodes.To assess the effect of the amount of organic amendments on soil nematode community structure and metabolic activity,the community composition,abundance,and metabolic footprints of soil nematodes were determined in a long-term field experiment with various amounts of organic amendment in Northeast China.Fertilization treatments included an unfertilized control(CK),chemical fertilizer without manure amendment(OM0),manure applied at 7.5 Mg ha^-1 plus chemical fertilizer(OM1),and manure applied at 22.5 Mg ha^-1 plus chemical fertilizer(OM2).A total of 46 nematode genera were found.Treatments with the largest amount of organic amendment had the smallest number of plant parasite genera(5),but a largest number of dominant genera(7).Soil nematodes,bacterivores,and fungivores were the most abundant in OM2,followed by OM1,and the lowest in OM0 and CK.Organic amendment increased the enrichment index(EI),and the large amount of organic amendment increased the metabolic footprints of bacterivore(Baf)and fungivore(Fuf)and enrichment footprint(Ef).The relationships between Baf(or Fuf)and the increases in soil organic carbon(?SOC)and total nitrogen(?TN)were stronger than those of bacterivore(or fungivore)abundance with?SOC and?TN,except for the relationship between bacterivore abundance and ?SOC.The EI and Ef were positively correlated with ?SOC and ?TN.These findings suggest that the amount of organic amendment affects soil nematode activity and function at entry levels in soil food web,and that metabolic footprints of soil nematodes may be better indicators than their abundances in assessing their relationships with soil nutrients. 展开更多
关键词 community composition ecosystem function enrichment footprint enrichment index metabolic activity soil food web trophic group
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A Conceptual Framework Evaluating Ecological Footprints and Monitoring Renewable Energy: Wind, Solar, Hydro, and Geothermal 被引量:2
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作者 Joanna Burger Michael Gochfeld 《Energy and Power Engineering》 2012年第4期303-314,共12页
With worldwide increases in energy consumption, and the need to increase reliance on renewable energy, we must examine ecological footprints of each energy source, as well as its carbon emissions. Renewable energy sou... With worldwide increases in energy consumption, and the need to increase reliance on renewable energy, we must examine ecological footprints of each energy source, as well as its carbon emissions. Renewable energy sources (wind, solar, hydro, geothermal) are given as the best examples of “green” energy sources with low carbon emissions. We provide a conceptual model for examining the ecological footprint of energy sources, and suggest that each resource needs continued monitoring to protect the environment, and ultimately human health. The effects and consequences of ecological footprint need to be considered in terms of four-compartments: underground (here defined as geoshed), surface, airshed, and atmosphere. We propose a set of measurement endpoints (metrics may vary), in addition to CO2 footprint, that are essential to evaluate the ecological and human health consequences of different energy types. These include traditional media monitoring (air, water, soil), as well as ecological footprints. Monitoring human perceptions of energy sources is also important for energy policy, which evolves with changes in population density, technologies, and economic consequences. While some assessment endpoints are specific to some energy sectors, others can provide crosscutting information allowing the public, communities and governments to make decisions about energy policy and sustainability. 展开更多
关键词 Airshed ATMOSPHERE Energy ECOLOGICAL FOOTPRINT Geoshed
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A fast computational method for the landing footprints of space-to-ground vehicles 被引量:2
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作者 LIU Qingguo LIU Xinxue +1 位作者 WU Jian LI Yaxiong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期1062-1076,共15页
Fast computation of the landing footprint of a space-to-ground vehicle is a basic requirement for the deployment of parking orbits, as well as for enabling decision makers to develop real-time programs of transfer tra... Fast computation of the landing footprint of a space-to-ground vehicle is a basic requirement for the deployment of parking orbits, as well as for enabling decision makers to develop real-time programs of transfer trajectories. In order to address the usually slow computational time for the determination of the landing footprint of a space-to-ground vehicle under finite thrust, this work proposes a method that uses polynomial equations to describe the boundaries of the landing footprint and uses back propagation(BP) neural networks to quickly determine the landing footprint of the space-to-ground vehicle. First, given orbital parameters and a manoeuvre moment, the solution model of the landing footprint of a space-to-ground vehicle under finite thrust is established. Second, given arbitrary orbital parameters and an arbitrary manoeuvre moment, a fast computational model for the landing footprint of a space-to-ground vehicle based on BP neural networks is provided.Finally, the simulation results demonstrate that under the premise of ensuring accuracy, the proposed method can quickly determine the landing footprint of a space-to-ground vehicle with arbitrary orbital parameters and arbitrary manoeuvre moments. The proposed fast computational method for determining a landing footprint lays a foundation for the parking-orbit configuration and supports the design of real-time transfer trajectories. 展开更多
关键词 space-to-ground vehicle landing footprint back propagation(BP)neural network fast computational method Pontryagin's minimum principle
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