Ports are crucial to the economy of many nations;thus, numerous studies have been conducted on port efficiency and productivity. This study analyses the efficiency and productivity of some major global ports namely, P...Ports are crucial to the economy of many nations;thus, numerous studies have been conducted on port efficiency and productivity. This study analyses the efficiency and productivity of some major global ports namely, Port of Singapore, Rotterdam, Antwerp and Durban. The main objectives of this study are to determine the level of operational efficiency of the mentioned ports, measure and evaluate the ports’ productivity changes and lastly to investigate the factors influencing the productivity changes of the ports studied. To achieve these objectives, Data Envelopment Analysis (DEA-BCC) model was used to determine the technical and operational efficiencies of the ports and Malmquist productivity index was employed to calculate the various productivity levels. The results of the study can guide stakeholders to formulate their operational strategies for port efficiency and productivity. The study also has policy suggestions that are uniquely targeted to Africa’s issues and potential.展开更多
Burundi faces major agricultural constraints, including land fragmentation, soil erosion, limited access to inputs, inadequate infrastructure and demographic pressures that exacerbate food insecurity. In order to addr...Burundi faces major agricultural constraints, including land fragmentation, soil erosion, limited access to inputs, inadequate infrastructure and demographic pressures that exacerbate food insecurity. In order to address the multiple challenges faced by farmers in rural areas, a study on improving agricultural productivity and food security in Burundi through optimized land use and diversified farming practices in agroforestry systems has been carried out. The study area is the communes of Giheta and Rutegama, all located in Burundi’s humid plateau livelihood zone, and involved 164 households grouped in coffee growing cooperatives supervised by the cooperative consortium COCOCA. The study uses a mathematical programming model to determine optimal crop selection based on factors such as production costs, yields and market demand. The findings of the study revealed significant insights into the demographic and socio-economic characteristics of the sampled population. Notably, 98.8% of respondents were engaged in agriculture, confirming the predominantly agricultural nature of Burundi. The results indicated that maize is the most important crop, occupying 33.9% of the average total cultivated area, followed by cassava at 26.5% and bananas at 19.4%. Together, these three crops accounted for a substantial portion of the total cultivated area, highlighting their significance in local agriculture. Beans and potatoes also play a role, occupying 14.4% and smaller areas, respectively. In terms of profitability, the study provides a detailed analysis of profit margins by crop. Bananas emerges as the most profitable crop, with a profit margin of 97.3%, followed closely by cassava at 96.1% and rice at 90.5%. These crops not only offered substantial yields relative to their production costs but also benefited from strong market demand. Other crops, such as beans (71.3%), coffee (70.3%), and vegetables (54.5%), also demonstrated considerable profitability, although they occupied smaller cultivated areas. Conversely, crops like pigeon peas (4.1%), potatoes (7.6%), and sweet potatoes (7.6%) exhibited the lowest profit margins, which may discourage farmers from investing in them unless other incentives, such as ecological benefits or local consumption needs, are present. Regarding the results, we therefore recommend to promote policies supporting agroforestry, improve market access and develop infrastructure to exploit these benefits.展开更多
Bangladesh’s principal grain,rice,is essential to the nation’s agricultural economy and food security.In light of the obstacles and possibilities for increasing domestic output,this study looks at Bangladesh’s food...Bangladesh’s principal grain,rice,is essential to the nation’s agricultural economy and food security.In light of the obstacles and possibilities for increasing domestic output,this study looks at Bangladesh’s food productivity and degree of self-sufficiency in rice production.Even though the nation has made significant progress in rice production,problems including population growth,land degradation,climate change,and poor infrastructure still have an impact on total productivity.To examine the trajectory of Bangladesh’s agricultural sector from 1973 to 2023 through the following economic lenses:agricultural input use,GDP contribution,employment rate,trade trends,critical development indicators,and domestic rice demand and production.The data were chosen based on their accessibility,geographical context,relevance to the study’s aims,and time constraints.According to this study,rice production increased from 9.9 million tons in 1973 to 39.1 million tons in 2023,demonstrating the nation’s continuous efforts to increase agricultural output to satisfy rising market demand.展开更多
Agriculture has become the backbone of most developing countries in the world, especially Tubah Sub-Division North West region, Cameroon. Following the COVID-19 pandemic and socio-political crisis that hit Cameroon’s...Agriculture has become the backbone of most developing countries in the world, especially Tubah Sub-Division North West region, Cameroon. Following the COVID-19 pandemic and socio-political crisis that hit Cameroon’s economy, there has been a steady increase in food insecurity, which has paved the way for farmers to adopt some sustainable strategies to boost agricultural productivity. Therefore, in trying to find models for survival and the pursuit of growth, farmers adopted some traditional farming methods and the use of local input as a means of sustainability. This study specifically seeks to analyze the effect of sustainability strategies on agricultural productivity in Tubah sub-division North West Region, Cameroon. The data was elicited via a survey questionnaire administered to 202 participating farmers selected from the different farmer organizations in the Tubah sub-division. Using cluster-sampling approach, proximity villages were grouped into four clusters of villages, and stratified sampling was used to select farmers to participate in the study. The objective of the study was achieved using OLS and quantile regression estimation techniques. The result showed evidence that the sustainability strategies implemented by the farmers decreased agricultural productivity in the 25th quantile, and at the 50th and 75th quantile, agricultural productivity still declined. This decline is because of unsustainable agricultural strategies like the use of slash and burn, the use of chemical fertilizers, inadequate capital, low level of education, inadequate farming experience, inadequate income, inadequate farm size, and the type of technology used for farming. Based on the findings, this study recommends that the government should organize training programs and seminars, subsidize farm inputs, grant agricultural loans to farmers, and initiate and support mechanized agriculture to boost agricultural productivity.展开更多
Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery(EUR).In this study,a hydraulic fracture stress sensitivity model...Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery(EUR).In this study,a hydraulic fracture stress sensitivity model is proposed to characterize the effect of pressure drop rate on fracture permeability.Furthermore,a production prediction model is introduced accounting for a non-uniform hydraulic fracture conductivity distribution.The results reveal that increasing the fracture conductivity leads to a rapid daily production increase in the early stages.However,above 0.50 D·cm,a further increase in the fracture conductivity has a limited effect on shale gas production growth.The initial production is lower under pressure-controlled conditions than that under pressure-release.For extended pressure control durations,the cumulative production initially increases and then decreases.For a fracture conductivity of 0.10 D·cm,the increase in production output under controlled-pressure conditions is~35%.For representative deep shale gas wells(Southern Sichuan,China),if the pressure drop rate under controlled-pressure conditions is reduced from 0.19 to 0.04 MPa/d,the EUR increase for 5 years of pressure-controlled production is 41.0 million,with an increase percentage of~29%.展开更多
Firm-level productivity analysis serves as a cornerstone for understanding the micro-foundations of economic growth,industrial competitiveness,and efficient resource allocation.This comprehensive review synthesizes an...Firm-level productivity analysis serves as a cornerstone for understanding the micro-foundations of economic growth,industrial competitiveness,and efficient resource allocation.This comprehensive review synthesizes and critically evaluates the primary statistical and econometric methodologies employed in the measurement and analysis of productivity at the firm level.We systematically delineate the evolution from traditional parametric techniques,such as production function estimation and Stochastic Frontier Analysis(SFA),to non-parametric approaches,including Data Envelopment Analysis(DEA)and the Malmquist Productivity Index.A significant focus is placed on addressing pervasive micro-level challenges,notably firm heterogeneity,measurement error,and endogeneity biases,which are endemic to firm-level data.The paper further explores recent methodological innovations,highlighting the integration of machine learning,quantile regression,and network analysis into the productivity research arsenal.By providing a structured guide for selecting and applying appropriate statistical tools,this review aims to equip researchers with the knowledge to conduct robust micro-level productivity analyses.Finally,we outline promising future research trajectories,emphasizing the potential of novel data sources and computational methods to deepen our understanding of productivity determinants.展开更多
Digital transformation provides enterprises with new development momenta.Understanding the relationship between digital transformation and total factor productivity(TFP)is essential.This study employs a fixedeffect mo...Digital transformation provides enterprises with new development momenta.Understanding the relationship between digital transformation and total factor productivity(TFP)is essential.This study employs a fixedeffect model and selects all Chinese A-share listed companies from 2007 to 2022 as the research sample.Internal control(IC)is introduced as a mechanistic variable.The results indicate that digital transformation significantly promotes both TFP and the effectiveness of IC.Moreover,effective IC plays a significant mediating role in the relationship between digital transformation and TFP.A heterogeneity analysis reveals that,compared to non-state-owned enterprises,state-owned enterprises can improve TFP more rapidly through digital transformation due to their resource advantages and policy support.On the one hand,these findings help enterprises better align their transformation strategies to maximize the benefits of digital transformation.On the other hand,they provide investors with insights into the transformation potential and future growth prospects of these enterprises.展开更多
This paper examines the impact of digital intelligence transformation on new quality productivity in enterprises in Fujian Province.It highlights the challenges these enterprises face,such as limited talent and infras...This paper examines the impact of digital intelligence transformation on new quality productivity in enterprises in Fujian Province.It highlights the challenges these enterprises face,such as limited talent and infrastructure,in adopting technologies like cloud computing,big data,and artificial intelligence.The research finds that digital intelligence can enhance innovation,efficiency,and market adaptability,driving significant improvements in productivity.The study emphasizes the need for organizational changes and government support to overcome barriers and accelerate transformation,offering valuable insights for both academia and industry.展开更多
The symbiotic relationships between trees and different mycorrhizal fungi affect the biodiversity-ecosystem functioning relationships within forest communities,particularly across different strata from the understorey...The symbiotic relationships between trees and different mycorrhizal fungi affect the biodiversity-ecosystem functioning relationships within forest communities,particularly across different strata from the understorey to the overstorey.However,current research on this relationship has not yet reached a definitive conclusion.In this study,we used regression analyses and structural equation modelling based on a 9-ha mixed broadleaved-Korean pine(Pinus koraiensis)forest plot to explore the effects of different types of mycorrhizal fungi(arbuscular mycorrhizal(AM)and ectomycorrhizal(EM)fungi)on the relationship between tree species diversity and productivity.The study found that the dominance and productivity of AM species increased in the understorey with increasing soil nutrients,whereas the productivity of EM species declined despite increasing diversity.In the overstorey,the productivity of AM species continued to increase with increasing soil nutrients,while that of EM species decreased due to increased competition.As for diversity-productivity relationships(DPRs),in the understorey,both AM and EM tree species demonstrated a positive DPR,suggesting the presence of the niche complementarity effect.In the overstorey,AM species continue to exhibit positive DPR due to their competitive advantage in nutrient-rich environments.In contrast,EM species exhibit negative DPR due to increased competition or less efficient resource use.Additionally,slope influenced forest productivity indirectly by altering the accumulation and distribution of soil nutrients,thereby affecting species distribution and growth conditions.This indirect effect highlights the potential negative impact of slope on soil nutrients within forest ecosystems,as well as its influence on the relationships between biodiversity and ecosystem functions.The study reveals how AM and EM trees influence forest productivity through distinct adaptability and competitive strategies across different forest strata,with a particular emphasis on the strata-dependent effects of mycorrhizal association on DPRs.This finding offers a new perspective on how mycorrhizal types modulate the complex relationships between biodiversity and ecosystem functions across various strata in temperate forests.展开更多
Selecting an appropriate planting density is an effective way to improve crop water productivity(WPC).However, there is a lack of research on the balance between evapotranspiration(ET) partitioning, water consumption,...Selecting an appropriate planting density is an effective way to improve crop water productivity(WPC).However, there is a lack of research on the balance between evapotranspiration(ET) partitioning, water consumption, and grain production under different summer maize planting densities. To close this knowledge gap, a two-year field experiment was conducted in the North China Plain(NCP) to reveal the effects of different planting densities(HD: 100,000 plants ha^(-1);MD: 78,000 plants ha^(-1);LD:56,000 plants ha^(-1)) on ET partitioning, grain yield, and water productivity of summer maize. The water-heat-carbon-nitrogen simulator(WHCNS) model was employed to calculate ET partitioning and perform scenario simulation after calibration and validation. The results showed that compared to the LD treatment, ET of the summer maize and grain yield in the MD and HD treatments significantly increased. Model simulations showed that the ratio of evaporation to ET ranged from 25.6% to 30.7%and reduced as increasing planting densities. Increasing planting density enhanced total transpiration of summer maize more than 20 mm, comparing to LD treatment, and the most significant differences between various planting densities appeared at the mid-growth stage(August 1 to 31). Scenario simulations indicated that grain yield and WPCof summer maize were consistently higher in wet and normal years compared to drought years, exhibiting a trend of initially increasing and then decreasing with increasing planting density. The highest grain yield and WPCof summer maize were observed at a planting density of approximately 80,000 plants ha^(-1). The results provide theoretical support for selecting a summer maize planting density and effectively utilizing agricultural water in the NCP.展开更多
Enhancing the carbon sink of terrestrial ecosystems is an essential nature-based solution to mitigate global warming and achieve the target of carbon neutrality.Over recent decades,China has launched a series of long-...Enhancing the carbon sink of terrestrial ecosystems is an essential nature-based solution to mitigate global warming and achieve the target of carbon neutrality.Over recent decades,China has launched a series of long-running and large-scale ambitious forestation projects.However,there is still a lack of year-to-year evaluation on the effects of afforestation on carbon sequestration.Satellite remote sensing provides continuous observations of vegetation dynamics and land use and land cover change,is becoming a practical tool to evaluate the changes of vegetation productivity driven by afforestation.Here,a spatially-explicit analysis was conducted by combining Moderate Resolution Imaging Spectroradiometer(MODIS)land cover and three up-to-date remote sensing gross primary productivity(GPP)datasets of China.The results showed that the generated afforestation maps have similar spatial distribution with the national forest inventory data at the provincial level.The accumulative areas of afforestation were 3.02×10^(5)km^(2)in China from 2002 to 2018,it was mainly distributed in Southwest(SW),South(Sou),Southeast(SE)and Northeast(NE)of China.Among them,SW possesses the largest afforestation sub-region,with an area of 9.38×10^(4)km^(2),accounting for 31.06%of the total.There were divergent trends of affores-tation area among different sub-regions.The southern sub-regions showed increasing trends,while the northern sub-regions showed decreasing trends.In keeping with these,the center of annual afforestation moved to the south after 2009.The southern sub-regions were the majority of the cumula-tive GPP,accounting for nearly 70%of the total.The GPP of new afforestation showed an increasing trend from 2002 to 2018,and the increasing rate was higher than existing forests.After afforestation,the GPP change of afforestation was higher than adjacent non-forest over the same period.Our work provides new evidence that afforestation of China has enhanced the carbon assimilation and will deepen our understanding of dynamics of carbon sequestration driven by afforestation.展开更多
Grassland is a key component of the ecosystem in the Qinghai Lake Basin,China.Understanding the effects of climate change and human activities on grassland productivity significantly improves ecological conservation a...Grassland is a key component of the ecosystem in the Qinghai Lake Basin,China.Understanding the effects of climate change and human activities on grassland productivity significantly improves ecological conservation and promotes sustainable vegetation growth in this area.Based on the net primary productivity(NPP)products of MOD17A3HGF(a moderate-resolution imaging spectroradiometer(MODIS)product that provides annual NPP at 500 m resolution)and meteorological data,we analyzed the spatial and temporal evolution of grassland NPP and its interaction with climate factors in the Qinghai Lake Basin from 2001 to 2022 via partial correlation and trend analysis methods.We also used the deflecting trend residual method and scenario analysis method to quantitatively assess the relative contributions of climatic factors and human activities to grassland NPP.The results revealed that:(1)during the past 22 a,grassland NPP increased considerably,with a gradient change from the northwest to the southeast of the study area;(2)sunshine duration,precipitation,and temperature positively influenced grassland NPP,with sunshine duration exerting a stronger effect on grassland NPP than precipitation and temperature;and(3)98.47%of the grassland in the study area was restored,with an average contribution of 65.00%from human activities and 35.00%from climatic alterations.Compared with climate change,human-induced factors had a greater effect on grassland NPP in this area.The results of the study not only provide important scientific support for ecological restoration and sustainable development of the basin but also offer new ideas for research on similar ecologically fragile areas.展开更多
In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social developmen...In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social development.Consequently,many domestic universities have introduced majors or courses related to big data.Among these,the Big Data Management and Applications major stands out for its interdisciplinary approach and emphasis on practical skills.However,as an emerging field,it has not yet accumulated a robust foundation in teaching theory and practice.Current instructional practices face issues such as unclear training objectives,inconsistent teaching methods and course content,insufficient integration of practical components,and a shortage of qualified faculty-factors that hinder both the development of the major and the overall quality of education.Taking the statistics course within the Big Data Management and Applications major as an example,this paper examines the challenges faced by statistics education in the context of emerging productive forces and proposes corresponding improvement measures.By introducing innovative teaching concepts and strategies,the teaching system for professional courses is optimized,and authentic classroom scenarios are recreated through illustrative examples.Questionnaire surveys and statistical analyses of data collected before and after the teaching reforms indicate that the curriculum changes effectively enhance instructional outcomes,promote the development of the major,and improve the quality of talent cultivation.展开更多
With the rapid development of new quality productivity and the in-depth advancement of digital transformation,vocational college libraries,as important supporting institutions for teaching and research,are facing the ...With the rapid development of new quality productivity and the in-depth advancement of digital transformation,vocational college libraries,as important supporting institutions for teaching and research,are facing the dual challenges of service model transformation and capacity improvement.Based on the changes in the demand for digital academic services under the background of new quality productivity,this paper systematically analyzes the current situation and problems of the digital academic service capabilities of librarians in vocational colleges,constructs a capability model including four dimensions:cognitive attitude,knowledge reserve,skill application,and communication and sharing,and proposes capability improvement strategies from aspects such as organizational incentives,professional training,service innovation,and technical support.Research shows that librarians in vocational colleges need to comprehensively enhance their digital academic service capabilities through paths such as concept renewal,skill strengthening,service transformation,and environment optimization,in order to adapt to the demands of educational reform in the era of new quality productivity.展开更多
Smart cities,a new kind of urbanization,offer a means of achieving the condition in which environmental conservation and economic growth are mutually beneficial.As a result,it is important to think about whether and h...Smart cities,a new kind of urbanization,offer a means of achieving the condition in which environmental conservation and economic growth are mutually beneficial.As a result,it is important to think about whether and how the development of smart cities might support the high-quality growth of urban economies.Based on the panel data of 163 prefecture-level cities in China from 2009–2018,the green total factor productivity(GTFP)of each prefecture-level city is measured using the SBM-GML model,and the appropriate spatial econometric model is screened by various types of tests.The spatial effect of smart city construction on GFTP is studied,and it is concluded that the pilot cities have a significant positive spatial spillover effect.The decomposition econometric model also shows that the pilot cities have a significant positive spatial spillover effect,and it also indicating that the smart city construction can also drive the surrounding cities to jointly improve the quality of economic development.Finally,the robustness of the spatial effect of smart city policy is also verified by changing the spatial measurement model and the type of spatial weight matrix,which also shows that the results of the spatial spillover effect of smart city construction are reliable.展开更多
This study aimed to model and identify the most productive cutting methods of tree plantations by comparing a forward felling technique(C)with sideways techniques outside(A and D)or inside cutting edge(B and E).Drone ...This study aimed to model and identify the most productive cutting methods of tree plantations by comparing a forward felling technique(C)with sideways techniques outside(A and D)or inside cutting edge(B and E).Drone video material of each tree was analyzed by comparing time distribution of work phases.The relation between this input data and harvester production data was analyzed by regression models.A quadratic model predicted productiv-ity precisely(R^(2)=0.95)and explained the effective-hour productivity in cutting cycle with dummy variables of har-vesting conditions.The productivity was explained by tree size and cutting cycle time,while effects of operator and harvester were eliminated by statistical analysis.In loblolly pine(Pinus taeda L.)plantations on flat terrain,cutting method B was 4.8 m3/E0h(effective working hour)more productive than method A,and 6.7 m^(3)/E0h than method C.In Sydney blue gum(Eucalyptus saligna Sm.)plantations,cutting method E was 1.8 m^(3)/E0h more productive than cut-ting method D on sloping terrain.Of the time-cycle vari-ables,time consumption of the“moving of tree”changed significantly between the cutting methods,of which the ones that used the sideways felling technique inside cutting edge were most efficient.This quadratic modeling structure can be recommended for precise studies in similar harvesting conditions.展开更多
The development of new quality productivity has set new requirements for vocational education.Vocational colleges need to integrate ideological and political education into professional courses to cultivate high-quali...The development of new quality productivity has set new requirements for vocational education.Vocational colleges need to integrate ideological and political education into professional courses to cultivate high-quality talents with both technical capabilities and political literacy.This paper analyzes the connotation of new quality productivity and its reshaping of vocational education,explores the challenges faced by the educational mechanism of Curriculumbased Political and Ideological Education(CPIE),and proposes a“three-dimensional synergy”practical pathway.That is,to effectively promote CPIE through three dimensions:the deep integration of cases with professional content,the enhancement of teaching effects using digitization,and the optimization of the course evaluation system.It aims to provide theoretical support and practical references for the reform of ideological and political education in vocational colleges.展开更多
Green technology innovation has gradually become an important driving force to promote new quality productivity.This paper constructs a quantitative index system of new quality productivity based on the three major el...Green technology innovation has gradually become an important driving force to promote new quality productivity.This paper constructs a quantitative index system of new quality productivity based on the three major elements of workers,labour objects and labour tools,and empirically analyses the impact of green technology innovation on the level of new quality productivity using spatial econometric model and VAR model.The result shows that:(1)The level of new quality productivity is not only affected by its own factors,but also by the significant spatial spillover effect between regions,especially in the case of strong geographic proximity,the interregional economic activities and resource allocation have a strong interaction and dependence.(2)The direct effect of green technology innovation is negative,mainly due to the high R&D investment and the short-term cost increase brought about by technological transformation,but its indirect effect is positive,showing that green technology has a positive effect on the new quality productivity enhancement of neighbouring regions through technology diffusion and cooperative innovation.(3)The eastern and western regions are affected by high upfront costs and transformation challenges,showing negative effects;while the central and northeastern regions benefit from policy support and industrial upgrading,showing positive effects.(4)Impulse response function analysis shows that the short-term impact of green technological innovation on new quality productivity is negative,but the long-term potential is significant,and the negative effect gradually diminishes over time.Based on this,this paper puts forward the suggestions of optimising the green innovation input structure,formulating regional differentiated policies and strengthening regional synergistic cooperation,which provide the theoretical basis and practical path for realising the green transformation and high-quality development of the economy.展开更多
The continuous innovation and widespread application of digital technology have expedited the transformation of productivity and presented an opportunity to achieve carbon peak and carbon neutrality.Digital new qualit...The continuous innovation and widespread application of digital technology have expedited the transformation of productivity and presented an opportunity to achieve carbon peak and carbon neutrality.Digital new quality productivity,characterized by the integration of advanced technologies,innovative business models,a new economic framework,and ongoing innovation,stands as a superior production factor.It plays a crucial role in fostering high-quality economic growth and leading efforts to meet the“dual carbon”objectives.Using panel data from Chinese prefecture-level cities from 2011 to 2022,this study employs various econometric models to empirically examine the impact and underlying mechanisms of digital new quality productivity on carbon emission reduction.The findings reveal that:(1)There exists a significant U-shaped nonlinear relationship between digital new quality productivity and carbon emission performance,with an inflection point at 0.2750.(2)Dual objective constraints significantly moderate the relationship between digital new productivity and carbon emission performance.Setting moderate economic growth targets positively influences the effect of digital new quality productivity on carbon emission performance.(3)The impact of digital new quality productivity on carbon emission performance varies considerably based on factors such as urban location,city size,resource endowment,and specific city characteristics.It is essential to focus on nurturing digital new quality productivity,exploring the integration of balanced economic growth objectives with environmental goals,and effectively leveraging the environmental benefits derived from the advancement of digital new quality productivity tailored to local contexts.展开更多
Integrating sprinkler with deficit irrigation system is a new approach to improve crop water productivity and ensure water and food security in arid areas of India.This study undertook a field experiment of sprinkler-...Integrating sprinkler with deficit irrigation system is a new approach to improve crop water productivity and ensure water and food security in arid areas of India.This study undertook a field experiment of sprinkler-irrigated cumin(variety GC-4)with a mini-lysimeter setup at an experimental research farm in Jodhpur,India during 2019-2022.Four irrigation treatments T_(1),T_(2),T_(3),and T4 were designed at irrigation water/cumulative pan evaporation(IW/CPE)of 1.0,0.8,0.6,and 0.4,respectively,with three replications.Daily actual crop evapotranspiration(ETc)was recorded and weekly soil moisture was monitored over the crop growth period.Quantities of applied water and drainage from mini-lysimeters were also measured at every irrigation event.Yield of cumin was recorded at crop maturity.Furthermore,change in farmer's net income from 1-hm2 land was computed based on the cost of applying irrigation water and considering yield variations among the treatments.Results indicated the highest mean seasonal actual ETc(371.7 mm)and cumin yield(952.47 kg/hm2)under T_(1)(with full irrigation).Under T_(2),T_(3),and T4,the seasonal actual ETc decreased by 10.4%,27.6%,and 41.3%,respectively,while yield declined by 5.0%,28.4%,and 50.8%,respectively,as compared to the values under T_(1).Furthermore,crop water productivity of 0.272(±0.068)kg/m3 under T_(2)was found relatively higher in comparison to other irrigation treatments,indicating that T_(2)can achieve improved water productivity of cumin in arid areas at an optimum level of deficit irrigation.The results of cost-economics indicated that positive change in farmer's net income from 1-hm2 land was 108.82 USD under T_(2),while T_(3)and T4 showed net losses of 5.33 and 209.67 USD,respectively.Moreover,value of yield response factor and ratio of relative yield reductions to relative ETc deficits were found to be less than 1.00 under T_(2)(0.48),and more than 1.00 under T_(3)(1.07)and T4(1.23).This finding further supports that T_(2)shows the optimized level of deficit irrigation that saves 20.0%of water with sacrificing 5.0%yield in the arid areas of India.Findings of this study provide useful strategies to save irrigation water,bring additional area under irrigation,and improve crop water productivity in India and other similar arid areas in the world.展开更多
文摘Ports are crucial to the economy of many nations;thus, numerous studies have been conducted on port efficiency and productivity. This study analyses the efficiency and productivity of some major global ports namely, Port of Singapore, Rotterdam, Antwerp and Durban. The main objectives of this study are to determine the level of operational efficiency of the mentioned ports, measure and evaluate the ports’ productivity changes and lastly to investigate the factors influencing the productivity changes of the ports studied. To achieve these objectives, Data Envelopment Analysis (DEA-BCC) model was used to determine the technical and operational efficiencies of the ports and Malmquist productivity index was employed to calculate the various productivity levels. The results of the study can guide stakeholders to formulate their operational strategies for port efficiency and productivity. The study also has policy suggestions that are uniquely targeted to Africa’s issues and potential.
文摘Burundi faces major agricultural constraints, including land fragmentation, soil erosion, limited access to inputs, inadequate infrastructure and demographic pressures that exacerbate food insecurity. In order to address the multiple challenges faced by farmers in rural areas, a study on improving agricultural productivity and food security in Burundi through optimized land use and diversified farming practices in agroforestry systems has been carried out. The study area is the communes of Giheta and Rutegama, all located in Burundi’s humid plateau livelihood zone, and involved 164 households grouped in coffee growing cooperatives supervised by the cooperative consortium COCOCA. The study uses a mathematical programming model to determine optimal crop selection based on factors such as production costs, yields and market demand. The findings of the study revealed significant insights into the demographic and socio-economic characteristics of the sampled population. Notably, 98.8% of respondents were engaged in agriculture, confirming the predominantly agricultural nature of Burundi. The results indicated that maize is the most important crop, occupying 33.9% of the average total cultivated area, followed by cassava at 26.5% and bananas at 19.4%. Together, these three crops accounted for a substantial portion of the total cultivated area, highlighting their significance in local agriculture. Beans and potatoes also play a role, occupying 14.4% and smaller areas, respectively. In terms of profitability, the study provides a detailed analysis of profit margins by crop. Bananas emerges as the most profitable crop, with a profit margin of 97.3%, followed closely by cassava at 96.1% and rice at 90.5%. These crops not only offered substantial yields relative to their production costs but also benefited from strong market demand. Other crops, such as beans (71.3%), coffee (70.3%), and vegetables (54.5%), also demonstrated considerable profitability, although they occupied smaller cultivated areas. Conversely, crops like pigeon peas (4.1%), potatoes (7.6%), and sweet potatoes (7.6%) exhibited the lowest profit margins, which may discourage farmers from investing in them unless other incentives, such as ecological benefits or local consumption needs, are present. Regarding the results, we therefore recommend to promote policies supporting agroforestry, improve market access and develop infrastructure to exploit these benefits.
文摘Bangladesh’s principal grain,rice,is essential to the nation’s agricultural economy and food security.In light of the obstacles and possibilities for increasing domestic output,this study looks at Bangladesh’s food productivity and degree of self-sufficiency in rice production.Even though the nation has made significant progress in rice production,problems including population growth,land degradation,climate change,and poor infrastructure still have an impact on total productivity.To examine the trajectory of Bangladesh’s agricultural sector from 1973 to 2023 through the following economic lenses:agricultural input use,GDP contribution,employment rate,trade trends,critical development indicators,and domestic rice demand and production.The data were chosen based on their accessibility,geographical context,relevance to the study’s aims,and time constraints.According to this study,rice production increased from 9.9 million tons in 1973 to 39.1 million tons in 2023,demonstrating the nation’s continuous efforts to increase agricultural output to satisfy rising market demand.
文摘Agriculture has become the backbone of most developing countries in the world, especially Tubah Sub-Division North West region, Cameroon. Following the COVID-19 pandemic and socio-political crisis that hit Cameroon’s economy, there has been a steady increase in food insecurity, which has paved the way for farmers to adopt some sustainable strategies to boost agricultural productivity. Therefore, in trying to find models for survival and the pursuit of growth, farmers adopted some traditional farming methods and the use of local input as a means of sustainability. This study specifically seeks to analyze the effect of sustainability strategies on agricultural productivity in Tubah sub-division North West Region, Cameroon. The data was elicited via a survey questionnaire administered to 202 participating farmers selected from the different farmer organizations in the Tubah sub-division. Using cluster-sampling approach, proximity villages were grouped into four clusters of villages, and stratified sampling was used to select farmers to participate in the study. The objective of the study was achieved using OLS and quantile regression estimation techniques. The result showed evidence that the sustainability strategies implemented by the farmers decreased agricultural productivity in the 25th quantile, and at the 50th and 75th quantile, agricultural productivity still declined. This decline is because of unsustainable agricultural strategies like the use of slash and burn, the use of chemical fertilizers, inadequate capital, low level of education, inadequate farming experience, inadequate income, inadequate farm size, and the type of technology used for farming. Based on the findings, this study recommends that the government should organize training programs and seminars, subsidize farm inputs, grant agricultural loans to farmers, and initiate and support mechanized agriculture to boost agricultural productivity.
基金supported by the Chongqing Natural Science Foundation Innovation and Development Joint Fund(CSTB2023NSCQ-LZX0078)the Science and Technology Research Program of Chongqing Municipal Education Commission(KJQN202201519),which are gratefully acknowledged.
文摘Pressure control in deep shale gas horizontal wells can reduce the stress sensitivity of hydraulic fractures and improve the estimated ultimate recovery(EUR).In this study,a hydraulic fracture stress sensitivity model is proposed to characterize the effect of pressure drop rate on fracture permeability.Furthermore,a production prediction model is introduced accounting for a non-uniform hydraulic fracture conductivity distribution.The results reveal that increasing the fracture conductivity leads to a rapid daily production increase in the early stages.However,above 0.50 D·cm,a further increase in the fracture conductivity has a limited effect on shale gas production growth.The initial production is lower under pressure-controlled conditions than that under pressure-release.For extended pressure control durations,the cumulative production initially increases and then decreases.For a fracture conductivity of 0.10 D·cm,the increase in production output under controlled-pressure conditions is~35%.For representative deep shale gas wells(Southern Sichuan,China),if the pressure drop rate under controlled-pressure conditions is reduced from 0.19 to 0.04 MPa/d,the EUR increase for 5 years of pressure-controlled production is 41.0 million,with an increase percentage of~29%.
文摘Firm-level productivity analysis serves as a cornerstone for understanding the micro-foundations of economic growth,industrial competitiveness,and efficient resource allocation.This comprehensive review synthesizes and critically evaluates the primary statistical and econometric methodologies employed in the measurement and analysis of productivity at the firm level.We systematically delineate the evolution from traditional parametric techniques,such as production function estimation and Stochastic Frontier Analysis(SFA),to non-parametric approaches,including Data Envelopment Analysis(DEA)and the Malmquist Productivity Index.A significant focus is placed on addressing pervasive micro-level challenges,notably firm heterogeneity,measurement error,and endogeneity biases,which are endemic to firm-level data.The paper further explores recent methodological innovations,highlighting the integration of machine learning,quantile regression,and network analysis into the productivity research arsenal.By providing a structured guide for selecting and applying appropriate statistical tools,this review aims to equip researchers with the knowledge to conduct robust micro-level productivity analyses.Finally,we outline promising future research trajectories,emphasizing the potential of novel data sources and computational methods to deepen our understanding of productivity determinants.
基金supported by Philosophy and Social Sciences Planning Project of Guangdong Province[Grant No.GD24CTS08].
文摘Digital transformation provides enterprises with new development momenta.Understanding the relationship between digital transformation and total factor productivity(TFP)is essential.This study employs a fixedeffect model and selects all Chinese A-share listed companies from 2007 to 2022 as the research sample.Internal control(IC)is introduced as a mechanistic variable.The results indicate that digital transformation significantly promotes both TFP and the effectiveness of IC.Moreover,effective IC plays a significant mediating role in the relationship between digital transformation and TFP.A heterogeneity analysis reveals that,compared to non-state-owned enterprises,state-owned enterprises can improve TFP more rapidly through digital transformation due to their resource advantages and policy support.On the one hand,these findings help enterprises better align their transformation strategies to maximize the benefits of digital transformation.On the other hand,they provide investors with insights into the transformation potential and future growth prospects of these enterprises.
基金Innovation and Entrepreneurship Training Program of Minjiang University,“Research on the Impact of Digital Intelligence Empowerment on the New Quality Productivity of Specialized and Innovative Enterprises and the Realization Path”(Project No.:202410395029)。
文摘This paper examines the impact of digital intelligence transformation on new quality productivity in enterprises in Fujian Province.It highlights the challenges these enterprises face,such as limited talent and infrastructure,in adopting technologies like cloud computing,big data,and artificial intelligence.The research finds that digital intelligence can enhance innovation,efficiency,and market adaptability,driving significant improvements in productivity.The study emphasizes the need for organizational changes and government support to overcome barriers and accelerate transformation,offering valuable insights for both academia and industry.
基金financially supported by the Natural Science Foundation of Heilongjiang Province of China(No.TD2023C006)the Fundamental Research Funds for the Central Universities(No.2572022DS13).
文摘The symbiotic relationships between trees and different mycorrhizal fungi affect the biodiversity-ecosystem functioning relationships within forest communities,particularly across different strata from the understorey to the overstorey.However,current research on this relationship has not yet reached a definitive conclusion.In this study,we used regression analyses and structural equation modelling based on a 9-ha mixed broadleaved-Korean pine(Pinus koraiensis)forest plot to explore the effects of different types of mycorrhizal fungi(arbuscular mycorrhizal(AM)and ectomycorrhizal(EM)fungi)on the relationship between tree species diversity and productivity.The study found that the dominance and productivity of AM species increased in the understorey with increasing soil nutrients,whereas the productivity of EM species declined despite increasing diversity.In the overstorey,the productivity of AM species continued to increase with increasing soil nutrients,while that of EM species decreased due to increased competition.As for diversity-productivity relationships(DPRs),in the understorey,both AM and EM tree species demonstrated a positive DPR,suggesting the presence of the niche complementarity effect.In the overstorey,AM species continue to exhibit positive DPR due to their competitive advantage in nutrient-rich environments.In contrast,EM species exhibit negative DPR due to increased competition or less efficient resource use.Additionally,slope influenced forest productivity indirectly by altering the accumulation and distribution of soil nutrients,thereby affecting species distribution and growth conditions.This indirect effect highlights the potential negative impact of slope on soil nutrients within forest ecosystems,as well as its influence on the relationships between biodiversity and ecosystem functions.The study reveals how AM and EM trees influence forest productivity through distinct adaptability and competitive strategies across different forest strata,with a particular emphasis on the strata-dependent effects of mycorrhizal association on DPRs.This finding offers a new perspective on how mycorrhizal types modulate the complex relationships between biodiversity and ecosystem functions across various strata in temperate forests.
基金supported in part by the Key R&D Program of Shandong Province,China (2023CXGC010703)the National Key Research and Development Program of China (2022YFD2300905-01)the Natural Science Foundation of Shandong Province,China (ZR2021MC123)。
文摘Selecting an appropriate planting density is an effective way to improve crop water productivity(WPC).However, there is a lack of research on the balance between evapotranspiration(ET) partitioning, water consumption, and grain production under different summer maize planting densities. To close this knowledge gap, a two-year field experiment was conducted in the North China Plain(NCP) to reveal the effects of different planting densities(HD: 100,000 plants ha^(-1);MD: 78,000 plants ha^(-1);LD:56,000 plants ha^(-1)) on ET partitioning, grain yield, and water productivity of summer maize. The water-heat-carbon-nitrogen simulator(WHCNS) model was employed to calculate ET partitioning and perform scenario simulation after calibration and validation. The results showed that compared to the LD treatment, ET of the summer maize and grain yield in the MD and HD treatments significantly increased. Model simulations showed that the ratio of evaporation to ET ranged from 25.6% to 30.7%and reduced as increasing planting densities. Increasing planting density enhanced total transpiration of summer maize more than 20 mm, comparing to LD treatment, and the most significant differences between various planting densities appeared at the mid-growth stage(August 1 to 31). Scenario simulations indicated that grain yield and WPCof summer maize were consistently higher in wet and normal years compared to drought years, exhibiting a trend of initially increasing and then decreasing with increasing planting density. The highest grain yield and WPCof summer maize were observed at a planting density of approximately 80,000 plants ha^(-1). The results provide theoretical support for selecting a summer maize planting density and effectively utilizing agricultural water in the NCP.
基金funded by the National Key Research and Development Program of China(Grant No.2020YFA0608103)the National Science Foundation of China(Grant Nos.42265012 and 31770765).
文摘Enhancing the carbon sink of terrestrial ecosystems is an essential nature-based solution to mitigate global warming and achieve the target of carbon neutrality.Over recent decades,China has launched a series of long-running and large-scale ambitious forestation projects.However,there is still a lack of year-to-year evaluation on the effects of afforestation on carbon sequestration.Satellite remote sensing provides continuous observations of vegetation dynamics and land use and land cover change,is becoming a practical tool to evaluate the changes of vegetation productivity driven by afforestation.Here,a spatially-explicit analysis was conducted by combining Moderate Resolution Imaging Spectroradiometer(MODIS)land cover and three up-to-date remote sensing gross primary productivity(GPP)datasets of China.The results showed that the generated afforestation maps have similar spatial distribution with the national forest inventory data at the provincial level.The accumulative areas of afforestation were 3.02×10^(5)km^(2)in China from 2002 to 2018,it was mainly distributed in Southwest(SW),South(Sou),Southeast(SE)and Northeast(NE)of China.Among them,SW possesses the largest afforestation sub-region,with an area of 9.38×10^(4)km^(2),accounting for 31.06%of the total.There were divergent trends of affores-tation area among different sub-regions.The southern sub-regions showed increasing trends,while the northern sub-regions showed decreasing trends.In keeping with these,the center of annual afforestation moved to the south after 2009.The southern sub-regions were the majority of the cumula-tive GPP,accounting for nearly 70%of the total.The GPP of new afforestation showed an increasing trend from 2002 to 2018,and the increasing rate was higher than existing forests.After afforestation,the GPP change of afforestation was higher than adjacent non-forest over the same period.Our work provides new evidence that afforestation of China has enhanced the carbon assimilation and will deepen our understanding of dynamics of carbon sequestration driven by afforestation.
基金financially supported by the Lanzhou Youth Science and Technology Talent Innovation Project(2023-QN-2)the Gansu Haizhi Plan Project(GSHZJH 12-2025-04)+1 种基金the National Key Research and Development Program of China(2019YFC0507404)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20100101)。
文摘Grassland is a key component of the ecosystem in the Qinghai Lake Basin,China.Understanding the effects of climate change and human activities on grassland productivity significantly improves ecological conservation and promotes sustainable vegetation growth in this area.Based on the net primary productivity(NPP)products of MOD17A3HGF(a moderate-resolution imaging spectroradiometer(MODIS)product that provides annual NPP at 500 m resolution)and meteorological data,we analyzed the spatial and temporal evolution of grassland NPP and its interaction with climate factors in the Qinghai Lake Basin from 2001 to 2022 via partial correlation and trend analysis methods.We also used the deflecting trend residual method and scenario analysis method to quantitatively assess the relative contributions of climatic factors and human activities to grassland NPP.The results revealed that:(1)during the past 22 a,grassland NPP increased considerably,with a gradient change from the northwest to the southeast of the study area;(2)sunshine duration,precipitation,and temperature positively influenced grassland NPP,with sunshine duration exerting a stronger effect on grassland NPP than precipitation and temperature;and(3)98.47%of the grassland in the study area was restored,with an average contribution of 65.00%from human activities and 35.00%from climatic alterations.Compared with climate change,human-induced factors had a greater effect on grassland NPP in this area.The results of the study not only provide important scientific support for ecological restoration and sustainable development of the basin but also offer new ideas for research on similar ecologically fragile areas.
文摘In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social development.Consequently,many domestic universities have introduced majors or courses related to big data.Among these,the Big Data Management and Applications major stands out for its interdisciplinary approach and emphasis on practical skills.However,as an emerging field,it has not yet accumulated a robust foundation in teaching theory and practice.Current instructional practices face issues such as unclear training objectives,inconsistent teaching methods and course content,insufficient integration of practical components,and a shortage of qualified faculty-factors that hinder both the development of the major and the overall quality of education.Taking the statistics course within the Big Data Management and Applications major as an example,this paper examines the challenges faced by statistics education in the context of emerging productive forces and proposes corresponding improvement measures.By introducing innovative teaching concepts and strategies,the teaching system for professional courses is optimized,and authentic classroom scenarios are recreated through illustrative examples.Questionnaire surveys and statistical analyses of data collected before and after the teaching reforms indicate that the curriculum changes effectively enhance instructional outcomes,promote the development of the major,and improve the quality of talent cultivation.
基金China Transportation Education Research Society Educational Science Research Topic“Research on Improving the Quality of Part-time Teachers in Transportation Vocational Colleges under the Background of New Quality Productivity”(JT2024YB245)。
文摘With the rapid development of new quality productivity and the in-depth advancement of digital transformation,vocational college libraries,as important supporting institutions for teaching and research,are facing the dual challenges of service model transformation and capacity improvement.Based on the changes in the demand for digital academic services under the background of new quality productivity,this paper systematically analyzes the current situation and problems of the digital academic service capabilities of librarians in vocational colleges,constructs a capability model including four dimensions:cognitive attitude,knowledge reserve,skill application,and communication and sharing,and proposes capability improvement strategies from aspects such as organizational incentives,professional training,service innovation,and technical support.Research shows that librarians in vocational colleges need to comprehensively enhance their digital academic service capabilities through paths such as concept renewal,skill strengthening,service transformation,and environment optimization,in order to adapt to the demands of educational reform in the era of new quality productivity.
基金Jilin Province Social Science Project:Path Analysis and Empirical Research on Empowering Rural Industry Integration with Digital Economy in Jilin Province 2023B40Key Project of Education Science Planning in Jilin Province:Exploration of Talent Training Model for Economic Statistics Majors in Universities Based on OBE Theory-Taking Jilin Jianzhu University as an Example.ZD22028.
文摘Smart cities,a new kind of urbanization,offer a means of achieving the condition in which environmental conservation and economic growth are mutually beneficial.As a result,it is important to think about whether and how the development of smart cities might support the high-quality growth of urban economies.Based on the panel data of 163 prefecture-level cities in China from 2009–2018,the green total factor productivity(GTFP)of each prefecture-level city is measured using the SBM-GML model,and the appropriate spatial econometric model is screened by various types of tests.The spatial effect of smart city construction on GFTP is studied,and it is concluded that the pilot cities have a significant positive spatial spillover effect.The decomposition econometric model also shows that the pilot cities have a significant positive spatial spillover effect,and it also indicating that the smart city construction can also drive the surrounding cities to jointly improve the quality of economic development.Finally,the robustness of the spatial effect of smart city policy is also verified by changing the spatial measurement model and the type of spatial weight matrix,which also shows that the results of the spatial spillover effect of smart city construction are reliable.
文摘This study aimed to model and identify the most productive cutting methods of tree plantations by comparing a forward felling technique(C)with sideways techniques outside(A and D)or inside cutting edge(B and E).Drone video material of each tree was analyzed by comparing time distribution of work phases.The relation between this input data and harvester production data was analyzed by regression models.A quadratic model predicted productiv-ity precisely(R^(2)=0.95)and explained the effective-hour productivity in cutting cycle with dummy variables of har-vesting conditions.The productivity was explained by tree size and cutting cycle time,while effects of operator and harvester were eliminated by statistical analysis.In loblolly pine(Pinus taeda L.)plantations on flat terrain,cutting method B was 4.8 m3/E0h(effective working hour)more productive than method A,and 6.7 m^(3)/E0h than method C.In Sydney blue gum(Eucalyptus saligna Sm.)plantations,cutting method E was 1.8 m^(3)/E0h more productive than cut-ting method D on sloping terrain.Of the time-cycle vari-ables,time consumption of the“moving of tree”changed significantly between the cutting methods,of which the ones that used the sideways felling technique inside cutting edge were most efficient.This quadratic modeling structure can be recommended for precise studies in similar harvesting conditions.
基金supported by the Beijing Municipal Commission of Education(Project Leader:Shang Wang,Project No.ZYJYDJ2024049).
文摘The development of new quality productivity has set new requirements for vocational education.Vocational colleges need to integrate ideological and political education into professional courses to cultivate high-quality talents with both technical capabilities and political literacy.This paper analyzes the connotation of new quality productivity and its reshaping of vocational education,explores the challenges faced by the educational mechanism of Curriculumbased Political and Ideological Education(CPIE),and proposes a“three-dimensional synergy”practical pathway.That is,to effectively promote CPIE through three dimensions:the deep integration of cases with professional content,the enhancement of teaching effects using digitization,and the optimization of the course evaluation system.It aims to provide theoretical support and practical references for the reform of ideological and political education in vocational colleges.
基金supported by the project of Non-Tax Revenue of Yunnan Provincial Department of Finance(Grant No.FSYJ202119).
文摘Green technology innovation has gradually become an important driving force to promote new quality productivity.This paper constructs a quantitative index system of new quality productivity based on the three major elements of workers,labour objects and labour tools,and empirically analyses the impact of green technology innovation on the level of new quality productivity using spatial econometric model and VAR model.The result shows that:(1)The level of new quality productivity is not only affected by its own factors,but also by the significant spatial spillover effect between regions,especially in the case of strong geographic proximity,the interregional economic activities and resource allocation have a strong interaction and dependence.(2)The direct effect of green technology innovation is negative,mainly due to the high R&D investment and the short-term cost increase brought about by technological transformation,but its indirect effect is positive,showing that green technology has a positive effect on the new quality productivity enhancement of neighbouring regions through technology diffusion and cooperative innovation.(3)The eastern and western regions are affected by high upfront costs and transformation challenges,showing negative effects;while the central and northeastern regions benefit from policy support and industrial upgrading,showing positive effects.(4)Impulse response function analysis shows that the short-term impact of green technological innovation on new quality productivity is negative,but the long-term potential is significant,and the negative effect gradually diminishes over time.Based on this,this paper puts forward the suggestions of optimising the green innovation input structure,formulating regional differentiated policies and strengthening regional synergistic cooperation,which provide the theoretical basis and practical path for realising the green transformation and high-quality development of the economy.
文摘The continuous innovation and widespread application of digital technology have expedited the transformation of productivity and presented an opportunity to achieve carbon peak and carbon neutrality.Digital new quality productivity,characterized by the integration of advanced technologies,innovative business models,a new economic framework,and ongoing innovation,stands as a superior production factor.It plays a crucial role in fostering high-quality economic growth and leading efforts to meet the“dual carbon”objectives.Using panel data from Chinese prefecture-level cities from 2011 to 2022,this study employs various econometric models to empirically examine the impact and underlying mechanisms of digital new quality productivity on carbon emission reduction.The findings reveal that:(1)There exists a significant U-shaped nonlinear relationship between digital new quality productivity and carbon emission performance,with an inflection point at 0.2750.(2)Dual objective constraints significantly moderate the relationship between digital new productivity and carbon emission performance.Setting moderate economic growth targets positively influences the effect of digital new quality productivity on carbon emission performance.(3)The impact of digital new quality productivity on carbon emission performance varies considerably based on factors such as urban location,city size,resource endowment,and specific city characteristics.It is essential to focus on nurturing digital new quality productivity,exploring the integration of balanced economic growth objectives with environmental goals,and effectively leveraging the environmental benefits derived from the advancement of digital new quality productivity tailored to local contexts.
文摘Integrating sprinkler with deficit irrigation system is a new approach to improve crop water productivity and ensure water and food security in arid areas of India.This study undertook a field experiment of sprinkler-irrigated cumin(variety GC-4)with a mini-lysimeter setup at an experimental research farm in Jodhpur,India during 2019-2022.Four irrigation treatments T_(1),T_(2),T_(3),and T4 were designed at irrigation water/cumulative pan evaporation(IW/CPE)of 1.0,0.8,0.6,and 0.4,respectively,with three replications.Daily actual crop evapotranspiration(ETc)was recorded and weekly soil moisture was monitored over the crop growth period.Quantities of applied water and drainage from mini-lysimeters were also measured at every irrigation event.Yield of cumin was recorded at crop maturity.Furthermore,change in farmer's net income from 1-hm2 land was computed based on the cost of applying irrigation water and considering yield variations among the treatments.Results indicated the highest mean seasonal actual ETc(371.7 mm)and cumin yield(952.47 kg/hm2)under T_(1)(with full irrigation).Under T_(2),T_(3),and T4,the seasonal actual ETc decreased by 10.4%,27.6%,and 41.3%,respectively,while yield declined by 5.0%,28.4%,and 50.8%,respectively,as compared to the values under T_(1).Furthermore,crop water productivity of 0.272(±0.068)kg/m3 under T_(2)was found relatively higher in comparison to other irrigation treatments,indicating that T_(2)can achieve improved water productivity of cumin in arid areas at an optimum level of deficit irrigation.The results of cost-economics indicated that positive change in farmer's net income from 1-hm2 land was 108.82 USD under T_(2),while T_(3)and T4 showed net losses of 5.33 and 209.67 USD,respectively.Moreover,value of yield response factor and ratio of relative yield reductions to relative ETc deficits were found to be less than 1.00 under T_(2)(0.48),and more than 1.00 under T_(3)(1.07)and T4(1.23).This finding further supports that T_(2)shows the optimized level of deficit irrigation that saves 20.0%of water with sacrificing 5.0%yield in the arid areas of India.Findings of this study provide useful strategies to save irrigation water,bring additional area under irrigation,and improve crop water productivity in India and other similar arid areas in the world.