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Co-incorporating green manure and crop straw increases crop productivity and improves soil quality with low greenhouse-gas emissions in a crop rotation
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作者 Na Zhao Xiquan Wang +6 位作者 Jun Ma Xiaohong Li Jufeng Cao Jie Zhou Linmei Wu Peiyi Zhao Weidong Cao 《The Crop Journal》 SCIE CSCD 2024年第4期1233-1241,共9页
In a nine-year field experiment in a wheat-maize-sunflower cropping system in Hetao Irrigation Area,Inner Mongolia,China,organic amendments applied as straw,manure,green manure,and the combination of green manure and ... In a nine-year field experiment in a wheat-maize-sunflower cropping system in Hetao Irrigation Area,Inner Mongolia,China,organic amendments applied as straw,manure,green manure,and the combination of green manure and straw increased wheat and maize yield,soil aggregate stability,and soil microbial activity in comparison with chemical fertilizer,without changing greenhouse gas emission intensity. 展开更多
关键词 green manure STRAW MANURE Soil organic carbon Soil quality Crop production Diversified cropping
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Transformation power or development pressure:economic growth targets and urban carbon productivity
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作者 Longtao Chen Yi Zheng +1 位作者 Xianfeng Han Juan Liu 《Chinese Journal of Population,Resources and Environment》 2024年第2期176-184,共9页
Maintaining moderate economic growth targets(EGTs)is the key for local governments to effectively implement the“carbon peak and carbon neutrality”goals under the refreshed development pattern.Utilizing panel data of... Maintaining moderate economic growth targets(EGTs)is the key for local governments to effectively implement the“carbon peak and carbon neutrality”goals under the refreshed development pattern.Utilizing panel data of 276 prefecture-level cities in China's Mainland from 2010 to 2020,and employing methods such as intermediary and threshold models,this study empirically analyzes the internal mechanism of EGT’s impact on urban carbon productivity(UCP).Our findings demonstrate that:①The overall EGT during the analyzed period is not conducive to improving UCP.This conclusion remains valid after a series of robustness tests.This effect is more pronounced in the central region and resource-based cities than in the east-west region and non resource-based cities.②EGT not only directly suppresses UCP but also exerts indirect negative impacts on UCP from three aspects:delaying the digital economy(DE),constraining financial expansion(FE),and hindering green technology innovation(GTI).This negative indirect effect is similar to or even surpasses the direct effect,suggesting that the internal relationship between EGT and“dual-carbon”goals should be re-evaluated from a new compound perspective.③EGT not only has a simple linear impact on UCP but also significantly exhibits a dynamic evolution pattern in inverted“U”shape.That is,as EGT continuously upgrades,a nonlinear impact on UCP emerges in the form of“promoting first,suppressing later”.This indicates that surpassing the“degree”limit for EGT will be detrimental to the improvement of UCP.This study broadens the scope of carbon productivity analysis by introducing a new perspective centered on EGT.The insights gleaned from this research offer valuable guidance for local governments to effectively manage economic growth expectations and promote the synchronized achievement of dual-carbon objectives. 展开更多
关键词 Economic growth target Urban carbon productivity Mediating effects Dynamic evolution
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Research on the Impact of China’s Foreign Trade Technology Spillover on Green Total Factor Productivity of Countries Along the“Belt and Road”:Based on the Institutional Quality Threshold Effect
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作者 Li Chai Longnan Ma Lingwei Meng 《Proceedings of Business and Economic Studies》 2024年第2期120-125,共6页
China’s growing trade with countries along the“Belt and Road”Initiative is accompanied by a focus on green development.Based on the panel data from 2007 to 2018,this paper establishes a threshold regression model t... China’s growing trade with countries along the“Belt and Road”Initiative is accompanied by a focus on green development.Based on the panel data from 2007 to 2018,this paper establishes a threshold regression model to empirically analyze the institutional quality threshold effect of China’s foreign trade technology spillover on the GTFP of countries along the“Belt and Road.”The results show that China’s foreign trade technology spillover has a significant institutional quality double threshold effect on the green total factor productivity of the countries along the“Belt and Road.”As the institutional quality of the countries along the“Belt and Road”crosses a specific threshold value,the impact of China’s foreign trade technology spillover on the green total factor productivity of the countries along the“Belt and Road”has a significant positive promoting effect,and corresponding suggestions are put forward. 展开更多
关键词 Technology spillover green total factor productivity Institutional quality Threshold effect
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Does innovative city pilot policy promote urban green growth in China?An analysis of green total factor productivity,2005-2020 被引量:1
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作者 Hao Zhang Wenqing Tao Jun He 《Chinese Journal of Population,Resources and Environment》 2023年第3期145-154,共10页
The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into... The innovative city pilot policy(ICPP)is an essential manifestation of China’s construction of an innovative and green-driven development country.We incorporated urban green total factor productivity(GTFP)growth into the evaluation of ICPP.Based on the panel data of 223 cities in China from 2005 to 2020,we used the difference-in-differences model to empirically assess the influence and mechanism of the ICPP on urban GTFP growth.The main results show that(i)The ICPP has maintained an effectively fluctuating promotion on urban GTFP growth,mainly manifested in the urban green technological progress improvement.(ii)The ICPP has urban heterogeneity in promoting GTFP growth in pilot cities,mainly affecting key cities such as provincial capitals.(iii)The interaction between the agglomeration of producer services and the ICPP inhibits GTFP growth in pilot cities. 展开更多
关键词 Innovative city pilot policy Urban green total factor productivity growth Industrial agglomerations Difference-in-differences model methodology
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Establishment of Regional Green Innovation Value Chains:A Case Study on Tackling the Impeded Diffusion of Green Products
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作者 Li Xiaoyan 《Contemporary Social Sciences》 2024年第4期1-16,共16页
The green innovation value chain is a key step in transforming green,innovative scientific,and technological achievements into productive forces.The establishment of green innovation value chains based on value distri... The green innovation value chain is a key step in transforming green,innovative scientific,and technological achievements into productive forces.The establishment of green innovation value chains based on value distribution rather than technical conditions can effectively overcome the common bottleneck faced by different nations during their green innovation endeavors,namely,the substitution of conventional products with green alternatives.This study investigates the impeded diffusion of green products and their underlying causes,analyzes the internal structure and mechanism of the green innovation value chain,and explores the establishment of regional green innovation value chains and the models available for value chain upgrading. 展开更多
关键词 green innovation value chain green products impeded diffusion
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Coupling and coordination relationship of tourism inclusive green growth system:Evidence from Shandong Province
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作者 Tianjun Xu Gangmin Weng Wei Guo 《Chinese Journal of Population,Resources and Environment》 2024年第3期334-342,共9页
Sustainable growth is a prerequisite for high-quality development,and inclusive green growth is regarded as an important way to realize sustainable growth.This paper constructs a tourism inclusive green growth index(I... Sustainable growth is a prerequisite for high-quality development,and inclusive green growth is regarded as an important way to realize sustainable growth.This paper constructs a tourism inclusive green growth index(IGGI)system based on the 2018 Asian Development Bank IGGI.Using Shandong Province from 2017 to 2019,the entropy weight method is utilized to explore the degree of coupling and coordination among the subsystems of tourism inclusive green growth.The study shows that:(1)the tourism IGGI continues to grow;(2)in the tourism inclusive green growth system,the social equity subsystem shows a trend of steady improvement;and(3)in the system,there is a slight discordance between the economic growth subsystem and the environmental sustainability subsystem.The study aims to provide the scientific basis for the high-quality development of tourism and theoretical support for the field of tourism and environmental sustainability. 展开更多
关键词 Tourism inclusive green growth system Coupled coordination Entropy law Tourism quality development
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Empirical Analysis of the Impact of Green Finance and Technological Progress on Total Factor Productivity in China’s Industrial Sector 被引量:1
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作者 Yingying Zhou Guoqiang Chen +3 位作者 Lujiu Huang Zhihao Lin Jing Jin Fengran Lu 《Proceedings of Business and Economic Studies》 2023年第6期39-44,共6页
The enhancement of industrial green total factor productivity is pivotal for achieving high-quality and sustainable economic development.This study assesses China’s performance using the SBM-GML model,employing provi... The enhancement of industrial green total factor productivity is pivotal for achieving high-quality and sustainable economic development.This study assesses China’s performance using the SBM-GML model,employing province-level panel data spanning from 2004 to 2020.Furthermore,we examine the influence of green finance and technological progress on industrial green total factor productivity using a spatial econometric model.The findings uncover that the relationship between the level of green financial development and industrial green total factor productivity follows a U-shaped curve.Initially,low levels of green financial development exert a suppressive effect on industrial green total factor productivity,proving ineffective in the short term.However,with the progression of green finance development,a positive and significant long-term impact on industrial green total factor productivity emerges.Moreover,technological progress demonstrates a noteworthy promotional effect on industrial green total factor productivity.The analysis delves deeper into revealing that industrial structure and environmental regulation intensity exhibit a significant negative relationship with industrial green total factor productivity.In contrast,both energy structure and education level showcase a substantial positive relationship with industrial green total factor productivity. 展开更多
关键词 Industrial green total factor productivity green finance Technological progress
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The impact of market coordination on urban green total factor productivity:An analysis of the mediating effect of factor misallocation
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作者 Yafei Wang Jinxin Yu +4 位作者 Zihan Zhao Huanhuan Huang Xi Wang Yuhang Zheng Jun He 《Chinese Journal of Population,Resources and Environment》 2023年第3期155-162,共8页
Promoting market coordination and enhancing the efficiency of green growth is a necessity for China’s effective economic development.Using panel data from 2007 to 2020,this paper conducts a comprehensive study on 226... Promoting market coordination and enhancing the efficiency of green growth is a necessity for China’s effective economic development.Using panel data from 2007 to 2020,this paper conducts a comprehensive study on 226 cities at the prefecture-level and above,combining theoretical analysis and empirical tests to systematically explore the impact of market cohesion on urban green total factor productivity(GTPF)and the mediating role of factor mismatch.Findings demonstrate that market coordination maximizes urban GTPF.At the mechanism level,factor mismatch plays a mediating role,and market coordination can enhance GTPF by addressing capital and labor mismatch.In terms of heterogeneity analysis,market coordination significantly promotes GTPF positively in the east-central region and negatively in the western region.In terms of technological progress and technical efficiency,the eastern region shows a larger significance than the central and western regions combined.In view of the above,the concept of market coordination development has been implemented to promote GTFP in cities. 展开更多
关键词 MARKET COORDINATION Urban green TOTAL factor productivity ELEMENTAL MISMATCH
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How do green product exports affect carbon emissions?Evidence from China 被引量:1
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作者 Kangyin Dong Jiaman Li Xiucheng Dong 《Chinese Journal of Population,Resources and Environment》 2023年第2期43-51,共9页
Green development has become an increasingly important global initiative.Therefore,this study focuses on the impact of green product exports on carbon emissions in China.Firm-level datasets are used to estimate provin... Green development has become an increasingly important global initiative.Therefore,this study focuses on the impact of green product exports on carbon emissions in China.Firm-level datasets are used to estimate provincial green product exports between 2001-2016.This study estimates the impact of green exports on carbon emissions using the system generalized method of moments methodology.In addition,heterogeneity and asymmetry of the nexus are explored.The following findings are highlighted:(1)China’s green product exports show a significant upward trend during the study period;(2)increased green product exports,especially those of high-technology manufacturers,can effectively mitigate CO_(2) emissions;(3)the influence of green product exports on carbon emissions is regional heterogeneous but consistent across quantiles;and(4)technique and scale effects are significant mediators,whereas the composition effect is not.These findings provide new evidence supporting methods to mitigate China’s CO_(2) emissions by adjusting green product export structures. 展开更多
关键词 green product exports CO_(2)emissions Mediation effect
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Agricultural productivity growth and technology progress in developing country agriculture: case study in China 被引量:5
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作者 ANDZIO-BIKA Herve Lezin W 卫龙宝 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第B08期172-176,共5页
The goal of this investigation was to analyze the impact of some production variables (input) on agricultural pro- ductivity growth (output) in China from 1989~2002. We selected through random sampling Zhejiang Provi... The goal of this investigation was to analyze the impact of some production variables (input) on agricultural pro- ductivity growth (output) in China from 1989~2002. We selected through random sampling Zhejiang Province for our disaggre- gate analysis with the use of Cobb-Douglas function. The estimation results showed that all key parameters are significant and are of the expected sign. Labor and that capital and land have positive impact on agricultural productivity growth. 展开更多
关键词 AGRICULTURE productivity growth China TECHNOLOGY
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Creative Industries Agglomeration,Regional Innovation and Productivity Growth in China 被引量:20
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作者 HONG Jin YU Wentao +1 位作者 GUO Xiumei ZHAO Dingtao 《Chinese Geographical Science》 SCIE CSCD 2014年第2期258-268,共11页
This paper falls into the broad area of economic geography and economics of creativity,and it presents an alternative approach to explain why total factor productivity(TFP)growth is different across China′s regions.I... This paper falls into the broad area of economic geography and economics of creativity,and it presents an alternative approach to explain why total factor productivity(TFP)growth is different across China′s regions.It establishes an empirical model to estimate the spatial agglomeration effects of creative industries on regional TFP growth,using China′s provincial panel data during the period of 2003 to 2010.We found that the creative industries agglomeration(CIA)has significant and positive impact on regional TFP growth.The result also implies that the CIA can facilitate regional TFP growth through promoting regional innovation instead of improving regional efficiency.Therefore,we argue that policy makers should take some measures to retain and establish more creative zones. 展开更多
关键词 creative industries spatial externality creativity industries agglomeration(CIA) total factor productivity(TFP) economic growth
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Productivity Growth in China's Agriculture During 1985-2010 被引量:24
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作者 LI Zhou ZHANG Hai-peng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第10期1896-1904,共9页
This paper made an empirical analysis of China's agricultural growth path and influential factors using the province-level panel data of agricultural inputs and outputs during 1985-2010.The findings indicate that the... This paper made an empirical analysis of China's agricultural growth path and influential factors using the province-level panel data of agricultural inputs and outputs during 1985-2010.The findings indicate that the increase in agricultural inputs and TFP contributed 40.6 and 55.2% to the agricultural output growth,respectively;China's agriculture had jumped out of the pattern which output growth was mainly driven by increasing input.Of the total inputs,chemical fertilizer had the most important contribution to the output growth,followed by mechanical inputs.The contribution of land and labor was negative.China's agricultural output growth belonged to the type of induced technology innovation.China's agricultural TFP growth had characteristics of fluctuations over time and unbalanced between regions,but the gap between the eastern,the middle,and the western regions has been narrowed. 展开更多
关键词 agricultural output growth input total factor productivity(TFP)
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Comparison of growth and nutrient uptake capacities of three dominant species of Qinhuangdao green tides
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作者 Hongbin Han Ruobing Wen +1 位作者 Hui Wang Sheng Zhao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期114-123,共10页
Since 2015, green tides have been blooming in offshore waters of Qinhuangdao, with serious impacts on the local ecological environment and tourism. Ulva australis, Bryopsis plumosa, and U. prolifera are the dominant s... Since 2015, green tides have been blooming in offshore waters of Qinhuangdao, with serious impacts on the local ecological environment and tourism. Ulva australis, Bryopsis plumosa, and U. prolifera are the dominant species of Qinhuangdao green tides, following a sequential succession pattern. Ulva prolifera is the dominant species,with the highest biomass and the greatest influence on the local ecological environment. To study the reason of green tide dominant species succession and U. profilera became the dominant species with the largest biomass,we compared and analyzed the growth and nutrient uptake capacity of the three algae. The results showed that temperature significantly affects the growth of the three species. Within the temperature range of the experimental setup, the optimum temperature for the growth of U. australis, B. plumosa and U. profilera is10℃, 15℃, and 20–25℃, respectively. Combined with the temperature variation trend during green tide bloom development, we believe that temperature is the key environmental factor for the succession of the dominant species. Ulva prolifera has a higher growth rate than U. australis and B. plumosa under the same nitrate,ammonium, and phosphate levels. Significant differences in the maximum absorption rate(R_(max)) and R_(max)/Ks(the relationship between uptake rate and substrate concentration) values indicated that U. prolifera had an apparent competitive advantage over U. australis and B. plumosa regarding nutrient uptake. Therefore, the strong growth and nutrient uptake capacities of U. prolifera might be the main reason for becoming the dominant species with the largest biomass in Qinhuangdao green tides. 展开更多
关键词 growth nutrient uptake dominant specie green tide Qinhuangdao
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Effects of drip and flood irrigation on carbon dioxide exchange and crop growth in the maize ecosystem in the Hetao Irrigation District,China 被引量:1
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作者 LI Chaoqun HAN Wenting PENG Manman 《Journal of Arid Land》 SCIE CSCD 2024年第2期282-297,共16页
Drip irrigation and flood irrigation are major irrigation methods for maize crops in the Hetao Irrigation District,Inner Mongolia Autonomous Region,China.This research delves into the effects of these irrigation metho... Drip irrigation and flood irrigation are major irrigation methods for maize crops in the Hetao Irrigation District,Inner Mongolia Autonomous Region,China.This research delves into the effects of these irrigation methods on carbon dioxide(CO_(2))exchange and crop growth in this region.The experimental site was divided into drip and flood irrigation zones.The irrigation schedules of this study aligned with the local commonly used irrigation schedule.We employed a developed chamber system to measure the diurnal CO_(2)exchange of maize plants during various growth stages under both drip and flood irrigation methods.From May to September in 2020 and 2021,two sets of repeated experiments were conducted.In each experiment,a total of nine measurements of CO_(2)exchange were performed to obtain carbon exchange data at different growth stages of maize crop.During each CO_(2)exchange measurement event,CO_(2)flux data were collected every two hours over a day-long period to capture the diurnal variations in CO_(2)exchange.During each CO_(2)exchange measurement event,the biological parameters(aboveground biomass and crop growth rate)of maize and environmental parameters(including air humidity,air temperature,precipitation,soil water content,and photosynthetically active radiation)were measured.The results indicated a V-shaped trend in net ecosystem CO_(2)exchange in daytime,reducing slowly at night,while the net assimilation rate(net primary productivity)exhibited a contrasting trend.Notably,compared with flood irrigation,drip irrigation demonstrated significantly higher average daily soil CO_(2)emission and greater average daily CO_(2)absorption by maize plants.Consequently,within the maize ecosystem,drip irrigation appeared more conducive to absorbing atmospheric CO_(2).Furthermore,drip irrigation demonstrated a faster crop growth rate and increased aboveground biomass compared with flood irrigation.A strong linear relationship existed between leaf area index and light utilization efficiency,irrespective of the irrigation method.Notably,drip irrigation displayed superior light use efficiency compared with flood irrigation.The final yield results corroborated these findings,indicating that drip irrigation yielded higher harvest index and overall yield than flood irrigation.The results of this study provide a basis for the selection of optimal irrigation methods commonly used in the Hetao Irrigation District.This research also serves as a reference for future irrigation studies that consider measurements of both carbon emissions and yield simultaneously. 展开更多
关键词 carbon dioxide exchange maize growth drip irrigation harvest index net primary productivity Hetao Irrigation District
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Technical Components of Total Factor Productivity Growth in Malaysian Manufacturing Industry 被引量:2
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作者 Nik Hashim Nik Mustapha Nik Mohd Hazrul Hashim Ridzuan Yacob 《Applied Mathematics》 2013年第9期1251-1259,共9页
This article attempts to disaggregate and explore the components of TFP growth that contribute to changes in output, scale of production, and allocative efficiency and technical efficiency of the Malaysian manufacturi... This article attempts to disaggregate and explore the components of TFP growth that contribute to changes in output, scale of production, and allocative efficiency and technical efficiency of the Malaysian manufacturing sector. The total factor productivity (TFP) concept defined as total output per unit of all inputs used in the production of an industry has gained a prominent place in academia. The investigation on TFP growth is obviously useful for identifying sources of output growth in the development of an industry. The TFP growth is often interchangeably understood as the technical progress or changes in technology as the sole contributor to economic development. Nonetheless there are other factors contributing to its substance. Knowledge on these technical changes would help decision makers to realize the strengths and weaknesses that contribute to the growth and development of an industry. Alternatively this research would be more beneficial in the case of cross-industry or cross-country comparative studies in order to plan for developmental goal. In such a case a model industry or country can be chosen that exhibits special growth features. 展开更多
关键词 TOTAL Factor productivity growth TECHNICAL Efficiency Scale Effect Stochastic production FRONTIER
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Climate change evidence in tree growth and stand productivity at the upper treeline ecotone in the Polar Ural Mountains 被引量:3
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作者 Nadezhda M.Devi Vladimir V.Kukarskih +2 位作者 Аrina A.Galimova Valeriy S.Mazepa Andrey A.Grigoriev 《Forest Ecosystems》 SCIE CSCD 2020年第1期76-91,共16页
Background:Recent warming is affecting species composition and species areal distribution of many regions.However,although most treeline studies have estimated the rates of forest expansion into tundra,still little is... Background:Recent warming is affecting species composition and species areal distribution of many regions.However,although most treeline studies have estimated the rates of forest expansion into tundra,still little is known about the long-term dynamic of stand productivity at the forest-tundra intersection.Here,we make use of tree-ring data from 350 larch(Larix sibirica Ledeb.)and spruce(Picea obovata Ledeb.)sampled along the singular altitudinal treeline ecotone at the Polar Urals to assess the dynamic of stand establishment and productivity,and link the results with meteorological observations to identify the main environmental drivers.Results:The analysis of stand instalment indicated that more than 90%of the living trees appeared after 1900.During this period,the stand became denser and moved 50m upward,while in recent decades the trees of both species grew faster.The maximum afforestation occurred in the last decades of the twentieth century,and the large number of encountered saplings indicates that the forest is still expanding.The upward shift coincided with a slight increase of May-August and nearly doubling of September-April precipitation while the increase in growth matched with an early growth season warming(June+0.27°C per decade since 1901).This increase in radial growth combined with the stand densification led to a 6-90 times increase of biomass since 1950.Conclusion:Tree-ring based twentieth century reconstruction at the treeline ecotone shows an ongoing forest densification and expansion accompanied by an increased growth.These changes are driven by climate change mechanism,whereby the leading factors are the significant increase in May-June temperatures and precipitation during the dormant period.Exploring of phytomass accumulation mechanisms within treeline ecotone is valuable for improving our understanding of carbon dynamics and the overall climate balance in current treeline ecosystems and for predicting how these will be altered by global change. 展开更多
关键词 POLAR URALS TREELINE productivity Climate change Radial growth Recruitment LARCH Spruce
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Counteraction of Nogo-A and axonal growth inhibitors by green tea polyphenols and other natural products 被引量:3
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作者 Tiffany K.Fan Usha Gundimeda +1 位作者 William J.Mack Rayudu Gopalakrishna 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第4期545-546,共2页
Neuronal injuries such as stroke,traumatic brain injury,and spinal cord injury are leading causes of major disability and death.Chronic therapy for these neuronal injuries requires the promotion of axonal regeneration... Neuronal injuries such as stroke,traumatic brain injury,and spinal cord injury are leading causes of major disability and death.Chronic therapy for these neuronal injuries requires the promotion of axonal regeneration from the remaining neurons(Schwab and Strittmatter,2014). 展开更多
关键词 EGCG Counteraction of Nogo-A and axonal growth inhibitors by green tea polyphenols and other natural products
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A Study of Optimum Switching Problem for Production Systems Considering Efficiency, Delivery Time and Green Evaluation
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作者 Jing Sun Mingjuan Zhao +1 位作者 Akihiro Yano Hisashi Yamamoto 《Journal of Computer and Communications》 2023年第2期158-171,共14页
This paper aims to derive the optimal switching strategy for production system considering efficiency, delivery time and green evaluation. Nowadays more and more manufacturing and logistics systems not only pursue bet... This paper aims to derive the optimal switching strategy for production system considering efficiency, delivery time and green evaluation. Nowadays more and more manufacturing and logistics systems not only pursue better work efficiency, but also focus on green energy evaluation issues. Cost reduction and shortening of delivery time are always important management issues in pursuit of efficiency and optimization of the entire production system because of global production competition. In a market situation where customer needs change in various ways, in particular, due to inadequate quality, changes in the local environment, natural disasters and so on. Therefore, prompt planning of management measures such as switching work processes and changing production methods has become an important issue. On the other hand, since the Paris Agreement came into effect, the construction of an environment-friendly production system has been required as an approach to environmental problems such as global warming. In this paper, we propose an optimum switching model of production systems considering efficiency, delivery time and green evaluation using a green evaluation index (GEC: Green Energy Coefficient). We also discuss the optimal switching strategy by numerical observation. 展开更多
关键词 green Evaluation Sustainable production Optimal Switching Problem production Networks Decarbonization Manufacture Management
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Growth characteristics of multipurpose tree species, crop productivity and soil properties in agroforestry systems under subtropical humid climate in India 被引量:3
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作者 M. Datta N. P. Singh 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第4期261-270,共10页
Multipurpose tree species (MPTs) were studied in an agroforestry arboretum under subtropical humid climate in Northeast India. Out of 12 MPTs planted under agroforestry systems, Acacia auriculiformis in spacing of 2... Multipurpose tree species (MPTs) were studied in an agroforestry arboretum under subtropical humid climate in Northeast India. Out of 12 MPTs planted under agroforestry systems, Acacia auriculiformis in spacing of 2 m × 2 m (2500 stems·hm^-2) could have the potentiality to meet the timber/fuelwood requirement due to its high wood production of 635 m^3·hm^-2 with mean annual increment (MAI) of 2.54×10^-2 m^3.treel.a^-1 in a short rotation period of 10 years. Thus, A. auriculiformis is a short rotation forest tree species suitable to grow in subtropical humid climate. On the other hand, at 16 years of age, Eucalyptus hybrid and Michelia champaca in spacing of 3 m × 3 m (1111 stems.hm^2) produced appreciably high timber volume of 315 m^3.hm^-2 and 165 m^3.hm^-2 with MAI of 1.77×10^-2 m^3.tree^-1·a^-1 and 0.92×10.2 m^3.tree^-1.a^-1, respectively. At 16 years of age, Gmelina arborea produced a timber volume of 147 m^3.hm^-2 with MAI of 1.47×10^-2 m^3.tree^-1.a^-1 followed by Samania saman (140 m^3.hm^-2), Albizziaprocera (113 m^3·hm^-2) and Tectona grandis (79 m3.hm^-2) with MAI of 1.40, 1.13 and 0.78 × 10^-2 m^3 .tree^-1a^-1, respectively in 4 m × 4 m spacing (625 stems.hm^-2). Gliricidia maculata and Leucaena leucocephala could be used as live fences around the farm boundary to supply their N-rich leaves for mulch as well as manure to crops. In agroforestry arboretum, direct seeded upland rice (Oryza sativa - variety, AR-11), groundnut (Arachis hypogaea - variety, JL-24) and sesamum (Sesamum indicum - variety, B-67) were grown during the initial period upto 8 years of tree establishment. Under other MPTs, there was a reduction in crop productivity as compared to open space. After 8 years of tree establishment, horti-silvi and silvi-pastoral systems were developed and pineapple (Ananas comosus - variety Queen), turmeric (Curcuma longa -variety RCT -1) and cowpea (Vigna sinensis - variety Pusa Barsati) as forage crop were raised. The productivity of pineapple, turmeric and cowpea was comparatively high under Azadirachta indica. The productivity of horticultural and forage crops in association with trees such as G. arborea, A. procera, S. saman, T. grandis and M. champaca of high timber value could be harnessed as viable agroforestry systems. Changes in soil properties were also monitored. Amelioration of soil acidity, increase in soil organic carbon, and enhanced humification of soil humus, high nutrient availability, low soil erodibility and high surface soil (0-15 cm) moisture availability were noted in soils under MPTs. 展开更多
关键词 Multipurpose trees Subtropical humid climate growth characteristics Timber volume Crop productivity Soil organic car-bon Soil humus Nutrient availability Soil erodibility indices Soil moisture.
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A Solar Energy System Design for Green Hydrogen Production in South-Western Nigeria, Lagos State, Using HOMER & ASPEN
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作者 Wilson Fidelis Ekpotu Joseph Taiwo Akintola +1 位作者 Martins Chineme Obialor Philemon Chukwuebuka Udom 《Open Journal of Optimization》 2023年第2期72-97,共26页
Solar system design for green hydrogen production has become the most prominent renewable energy research area, and this has also actively fueled the desire to achieve net-zero emissions. Hydrogen is a promising energ... Solar system design for green hydrogen production has become the most prominent renewable energy research area, and this has also actively fueled the desire to achieve net-zero emissions. Hydrogen is a promising energy carrier because it possesses more energy capacity than fossil fuels and the abundant nature of renewable energy systems can be utilized for green hydrogen production. However, the design of an optimized electrical energy system required for hydrogen production is crucial. Solar energy is indeed beneficial for green hydrogen production and this research designed, discussed, and provided high-level research on HOMER design for green hydrogen production and deployed the energy requirement with ASPEN Plus to optimize the energy system, while also incorporating fuzzy logic and PID control approaches. In addition, a promising technology with a high potential for renewable hydrogen energy is the proton exchange membrane (PEM) electrolyzer. Since its cathode (hydrogen electrode) may be operated over a wide range of pressure, a control process must be added to the system in order for it to work dynamically efficiently. This system can be characterized as an analogous circuit that consists of a resistor, capacitor, and reversible voltage. As a result, this research work also explores the Fuzzy-PID control of the PEM electrolysis system. Both the PID and Fuzzy Logic control systems were simulated using the control simulation program Matlab R2018a, which makes use of Matlab script files and the Simulink environment. Based on the circuit diagram, a transfer function that represents the mathematical model of the plant was created, and the PEM electrolysis control system is determined to be highly significant and applicable to the two control systems. The PI controller, however, has a 30.8% overshoot deficit, but when the fuzzy control system is compared to the PID controller, it is found that the fuzzy control system achieves stability more quickly, demonstrating its benefit over PID. 展开更多
关键词 Homer Solar Design Solar Energy Renewable Energy green Hydrogen production Fuzzy Logic HOMER
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