With China’s economic development entering a new normal,high-quality regional economic development has become an important goal of current economic development.As one of the important means to promote high-quality de...With China’s economic development entering a new normal,high-quality regional economic development has become an important goal of current economic development.As one of the important means to promote high-quality development of the regional economy,industrial policies are increasingly receiving attention in terms of their role and impact.This article mainly conducts an in-depth analysis of the mechanism and impact path of industrial policies,exploring the role and impact of industrial policies in promoting high-quality regional economic development.Firstly,industrial policies play an important role in promoting high-quality regional economic development.Secondly,the impact path of industrial policies on the high-quality development of the regional economy mainly includes promoting industrial structure upgrading,promoting technological innovation,guiding resource allocation,and enhancing enterprise competitiveness.Therefore,it is necessary to increase research and practice on industrial policies,continuously optimize policy measures,and promote high-quality development of the regional economy.展开更多
The“one-stop”student community provides new support for innovation and entrepreneurship education in universities.Integrating innovation and entrepreneurship education into the“one-stop”student community work enri...The“one-stop”student community provides new support for innovation and entrepreneurship education in universities.Integrating innovation and entrepreneurship education into the“one-stop”student community work enriches course materials,integrates teacher resources,improves students’participation in innovation and entrepreneurship,and solves problems such as low student participation,lack of course resources,insufficient teacher resources,and single evaluation methods in traditional classrooms.Through various means such as exploring course resources,innovating management models,and strengthening team construction,the role of“one-stop”student communities in innovation and entrepreneurship education has been fully utilized,promoting the development of innovation and entrepreneurship education.展开更多
Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the perio...Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the period of 1958-2007 in the Kaidu River watershed,this paper analyzed the changes in air temperature,precipitation and runoff and revealed the direct and indirect impacts of daily air temperature and precipitation on daily runoff by path analysis.The results showed that mean temperature time series of the annual,summer and autumn had a significant fluctuant increase during the last 50 years(P 0.05).Only winter precipitation increased significantly(P 0.05) with a rate of 1.337 mm/10a.The annual and winter runoff depthes in the last 50 years significantly increased with the rates of 7.11 mm/10a and 1.85 mm/10a,respectively.The driving function of both daily temperature and precipitation on daily runoff in annual and seasonal levels is significant in the Kaidu River watershed by correlation analysis.The result of path analysis showed that the positive effect of daily air temperature on daily runoff depth is much higher than that of daily precipitation in annual,spring,autumn and winter,however,the trend is opposite in summer.展开更多
Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental facto...Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental factors controlling runoff and sediment yields in 15 runoff plots in study area by soil sampling,laboratory analysis,stepwise regression analysis and path analysis,and to establish the main control environmental factors that affect runoff and sediment yields. The results showed that soil bulk density,herbaceous cover,slope,and canopy density were the significant factors controlling runoff,and the direct path coefficient of each factor was ranked as canopy closure(-0. 628) > litter thickness(-0. 547) > bulk density( 0. 509) > altitude( 0. 289). The indirect path coefficient was ranked as soil bulk density( 0. 354) >litter thickness(-0. 169) > altitude( 0. 126) > canopy closure(-0. 104). Therefore,canopy closure and litter thickness mainly had direct effects on runoff,while soil bulk density mainly had indirect effects through their contributions to other factors. Herbaceous cover,litter thickness,slope,canopy density,and altitude were the significant factors controlling sediment yields. The direct path coefficient of each factor was ranked as herbaceous cover(-0. 815) > litter thickness(-0. 777) > canopy closure(-0. 624) > slope( 0. 620). The indirect path coefficient was ranked as slope( 0. 272) > litter thickness(-0. 131) > canopy closure(-0. 097) > herbaceous cover(-0. 084). Therefore,herbaceous cover and litter thickness mainly had direct effects on sediment yields,while slope mainly had indirect effects through their contributions to other factors. All the selected environmental factors jointly explained 85. 5% and 78. 3% of runoff and sediment yield variability,respectively. However,there were large values of remaining path coefficients of other factors influencing runoff and sediment yields,which indicated that some important factors are not included and should be taken into account.展开更多
In the paper presented, 99 single seed descent barley lines as well as their parental forms Roland and Apex were studied. The grain weight components and their interrelations were analyzed using simple coefficients of...In the paper presented, 99 single seed descent barley lines as well as their parental forms Roland and Apex were studied. The grain weight components and their interrelations were analyzed using simple coefficients of correlation. The direct and indirect effects of such components on grain weight per plant and 1 000-grain weight were estimated using path analysis. In the 2006 and 2007, the spike length and number of spikelets per spike were the determinants of grain weight. Genetic parameters as additive and epistasis effects were estimated for all studied traits. The results indicate the importance of both additive and epistasis gene effects of number of spikes per plant, grain weight per spike, grain number per plant and grain weight per plant in this study.展开更多
With the rapid development of science and technology and the increasing popularity of the Internet,the number of network users is gradually expanding,and the behavior of network users is becoming more and more complex...With the rapid development of science and technology and the increasing popularity of the Internet,the number of network users is gradually expanding,and the behavior of network users is becoming more and more complex.Users’actual demand for resources on the network application platform is closely related to their historical behavior records.Therefore,it is very important to analyze the user behavior path conversion rate.Therefore,this paper analyses and studies user behavior path based on sales data.Through analyzing the user quality of the website as well as the user’s repurchase rate,repurchase rate and retention rate in the website,we can get some user habits and use the data to guide the website optimization.展开更多
The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.Howev...The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantified the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed significant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientific basis for reasonable fertilization in tea gardens and tea quality improvement.展开更多
Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there ar...Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there are no reports on traits suitable for direction selection and reproductive productivity of Kumamoto oysters of different ages.In this study,path analysis and one-way ANOVA were used to explore the influential indices of oyster body weight and fecundity.The results showed that shell height was the main factor affecting the body weight of Kumamoto oysters at one-year-old and two-year-old,followed by shell length.Body weight was the main factor influencing fecundity,and shell height showed a significant correlation with fecundity.Therefore,shell height should be considered the first parameter for selection when selecting Kumamoto oysters for body weight as the direct selection target.When one-year-old and two-year-old Kumamoto oysters were selected as parents from Xiangshan Bay,hatching parameters and growth parameters of F1 generation larvae were measured.The fecundity and egg diameters were 1.72×10^(6)and 46.60±3.62μm,respectively,which were significantly greater than one-aged oysters(5.86×10^(5),40.26±3.52μm).The hatching parameters(fertilized egg size,fertilization rate,and hatching rate)and larval growth performance(D-stage veliger and veliger)were similar and did not differ significantly(P>0.05),and after metamorphosis,there was also no significant difference in shell height size at 40 days of age(P>0.05).Therefore,there was no significant effect of age on reproduction,larval development,and the early growth of Kumamoto oysters.These results could provide a basis for parental sources and proper traits for Kumamoto oyster selection,which is beneficial to developing and utilizing this excellent germplasm resource.展开更多
This study links social capital with people’s health and well-being using data from the seventh wave of the World Value Survey,logistic regression,and path analysis.The study’s findings show that happiness and life ...This study links social capital with people’s health and well-being using data from the seventh wave of the World Value Survey,logistic regression,and path analysis.The study’s findings show that happiness and life satisfaction are two different measures of the same construct,or well-being.The determinants of each are also characterised differently:while life satisfaction is more of a stable and relative measure and is more strongly influenced by civic cooperation,social participation,and educational attainment,happiness is more of an unstable measure and is more strongly influenced by community belonging,trust and confidence aggregates,including employment and location of residence of an individual.Moreover,freedom of choice,financial satisfaction or social comparison,and state of health were the most important factors influencing happiness and life satisfaction.The findings also show that self-reported health(SRH)has a greater impact on happiness than a measure of life satisfaction.Path analysis shows out of the three other components of social capital—community belonging,civic engagement,and social participation—trust and confidence aggregates are the ones that have the biggest impact on increased social capital.For both well-being measures,SRH mediated the relationship.The life satisfaction measure had a higher level of mediation of SRH than happiness,but social capital had a smaller direct impact on life satisfaction than on happiness.SRH was found to be partially mediating this relationship for both happiness and life satisfaction measures,which means that people with higher social capital reported feeling better off.展开更多
Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The r...Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF inoculation.AMF led to an increase in the net photosynthetic rate and antioxidant enzyme activity of rice.In the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control group.Conversely,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the seeds.Path coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in seeds.The translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal effects.Our study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF.展开更多
The physiological characters and growth of tomato(Solanum lycopersicum L.)were recorded to be largely affected by different levels of irrigation.The objectives of this research were to determine the effects of deficit...The physiological characters and growth of tomato(Solanum lycopersicum L.)were recorded to be largely affected by different levels of irrigation.The objectives of this research were to determine the effects of deficit irrigation and rain shelters on sap flow,relative water content and the relationship between sap flow and environmental parameters.Experiments under rain shelters conditions were conducted in southern China during the growing seasons in 2012.The threshold of irrigation was designed at 80%field capacity during the whole period(T1,the control),and 30%,40%and 50%decreased water of T1 were applied as the treatments of T2,T3 and T4.The plants subjected to water stress exhibited a decrease in the values of sap flow rate and relative water content.Calculation of 95%confidence level revealed a significant difference of sap flow rate in T4 and T3 as well as the control on sunny and rainy days.The diurnal variation of the sap flow showed a single peak curve on sunny day,while it demonstrated irregular multi-peak variation on rainy days.The study also showed that the most sensitive environmental indicator affecting sap flow was solar radiation,followed by air temperature and vapour pressure deficit.Direct path coefficient was basically consistent with the coefficient of correlation,but there was slight difference between the total contribution R2 and that of variable factors.展开更多
Background Tuberculosis(TB)is one of the top 10 causes of death in the world.Since Directly Observed Therapy(DOT)as a core strategy for the global TB control are not applicable to all types of TB patients,and self-man...Background Tuberculosis(TB)is one of the top 10 causes of death in the world.Since Directly Observed Therapy(DOT)as a core strategy for the global TB control are not applicable to all types of TB patients,and self-management of TB patients(SMTP)as a patient-centered supervision type is a supplement to DOT and can improve TB case management.However,the factors related to SMTP are complex and need more study.This study aimed at identifying the determinants of SMTP and examining the direct/indirect effects of these determinants.Methods The purposive sampling technique was used to select study sites and participants were recruited from the study sites by the consecutive sampling method.The PRECEDE model was used as the framework to analyze the determinants of SMTP.The responses of TB patients were acquired via a questionnaire survey for data collection.A Pearson correlation analysis was used to define the relationship between the predisposing,enabling,reinforcing factors with SMTP behaviors.A regression-based path analysis was used to determine the action paths of the predisposing,enabling,and reinforcing factors on SMTP behaviors.Results The predisposing(TB knowledge),enabling[health education and healthcare workers(HCWs)support],reinforcing factors(family support)had significant positive correlations with SMTP behaviors(P<0.05).The predisposing,enabling,reinforcing factors were positively correlated with each other(r=0.123‒0.918,P<0.05),except for family support and HCWs support.The predisposing factors(TB knowledge,β=0.330)and the enabling factors(HCWs support,β=0.437)had direct effects on SMTP behaviors.The enabling factors(health education and HCWs support)and the reinforcing factors(family support)had indirect effects on SMTP behaviors.Conclusions This study revealed the effects and action path of TB knowledge,health education,HCWs support,and family support on SMTP behaviors via a path analysis.Assessing patient’s needs for SMTP along with promoting effective TB health education and providing firm support from HCWs and family members are potential strategies to promote SMTP behaviors.展开更多
The objective of this study was to determine the relationship between PM10 and PM2.5 levels as related to meteorological conditions and traffic flow using both a linear regression analysis and a path analysis. The Par...The objective of this study was to determine the relationship between PM10 and PM2.5 levels as related to meteorological conditions and traffic flow using both a linear regression analysis and a path analysis. The Particulate matter(PM) samples were collected from Sukhumvit road, Bangkok, Thailand, at both open(104 samples) and covered(92 samples)areas along the road. Fifteen percent of all samples were separated before the statistical models were run and used for model validation. The results from the path analysis were more elaborate than those from the linear regression, thus indicating that meteorological conditions had a direct effect on the particulate levels and that the effects of traffic flow were more variable in open areas. The model also indicated that meteorological conditions had an indirect effect and that traffic flow had a direct effect on particulate levels in covered areas. The model validation results indicated that for open areas, the R^2 values were not very different between the path analysis and the linear regression model, but that the path analysis was more accurate than the linear regression model at very low PM concentrations. At high PM concentrations, the path analysis model also had a better fit than did the linear regression, so the predictions from the path analysis model were more accurate than those from the linear regression.展开更多
Purpose-The purpose of this article is to conduct a main path analysis of 627 articles on the theme of Pythagorean fuzzy sets(PFSs)in the Web of Science(WoS)from 2013 to 2020,to provide a conclusive and comprehensive ...Purpose-The purpose of this article is to conduct a main path analysis of 627 articles on the theme of Pythagorean fuzzy sets(PFSs)in the Web of Science(WoS)from 2013 to 2020,to provide a conclusive and comprehensive analysis for researchers in this field,and to provide a study on preliminary understanding of PFSs.Design/methodology/approach-The research topic of Pythagorean fuzzy fields,through keyword extraction and describing the changes in characteristic themes over the past eight years,are firstly examined.Main path analysis,including local and global main paths and key route paths,is then used to reveal the most influential relationships between papers and to explore the trajectory and structure of knowledge transmission.Findings-The application of Pythagorean fuzzy theory to the field of decision-making has been popular,and combinations of the traditional Pythagorean fuzzy decision-making method with other fuzzy sets have attracted widespread attention in recent years.In addition,over the past eight years,research interest has shifted to different types of PFSs,such as interval-valued PFSs.Research limitations/implications-This paper implicates to investigate the growth in certain trends in the literature and to explore the main paths of knowledge dissemination in the domain of PFSs in recent years.Originality/value-This paper aims to identify the topics in which researchers are currently interested,to help scholars to keep abreast of the latest research on PFSs.展开更多
Geospatial technology is a useful tool when identifying land corridors for transportation networks. The primary transit corridor between Los Angeles, CA and Las Vegas, NV is Interstate-15, approximately a four-hour au...Geospatial technology is a useful tool when identifying land corridors for transportation networks. The primary transit corridor between Los Angeles, CA and Las Vegas, NV is Interstate-15, approximately a four-hour automobile trip without traffic. Virgin Trains USA LLC proposes an alternative means of travel by constructing a high-speed railway along Interstate-15 connecting Las Vegas and Victorville, CA. This study uses least-cost path analysis to propose an optimized alternative corridor for Virgin Trains’ proposed high-speed railway through a system facilitated road and rail accessibility analysis. Previous research using least-cost path and accessibility methodologies evaluated the results of proposed high-speed railway corridors and the system facilitated accessibility changes by visually inspecting deviations from a planned corridor using single or multiple cost criteria as inputs for a weighted cost surface. However, robust analyses of previous least-cost path studies’ corridors are lacking. This proof-in-concept study proposes a less costly corridor through least-cost path analysis and measures the social impact on the stakeholders of a high-speed railway transportation system through system facilitated accessibility. This study’s proposed alternative corridor is 31% shorter than Virgin Trains’ planned corridor and system facilitated accessibility to Las Vegas, NV is increased in 99.74% of Los Angeles County’s census tracts. These results support this study’s position that geospatial technology can support transportation planning in a comprehensive method that considers the transportation corridor and benefits its stakeholders.展开更多
Irrigated agriculture has tripled since 1950,accounting for 20%of the global arable land and 40%of food production.Irrigated agriculture increases food security yet has controversial implications for global climate ch...Irrigated agriculture has tripled since 1950,accounting for 20%of the global arable land and 40%of food production.Irrigated agriculture increases food security yet has controversial implications for global climate change.Most previous studies have calculated carbon emissions and their composition in irrigated areas using the engineering approach to life-cycle assessment.By combining life cycle assessment(LCA)-based carbon emissions accounting with econometric models such as multiple linear regression and structural equation modeling(SEM),we conducted an interdisciplinary study to identify the influencing factors and internal mechanisms of the carbon footprint(CFP)of smallholder crop cultivation on irrigation reform pilot areas.To this end,we investigated corn and potato production data in the 2019–2020 crop years for 852 plots of 345 rural households in six villages(two irrigation agriculture pilot villages and four surrounding villages as controls)in Southwest China.The crop CFP in the irrigation agriculture pilot areas was significantly lower than in non-reform areas.Irrigation reforms mainly impacted the crop CFP through four intermediary effects:the project(implementation of field irrigation channels),technology(improving adoption of new irrigation technologies),management(proper irrigation operation and maintenance),and yield effects.All effects inhibited the CFP,except for the project effect that promotes carbon emissions.Among them,yield increase has the greatest impact on reducing CFP,followed by management and technology effects.Furthermore,planting practices,individual characteristics,and plot quality significantly impacted the crop CFP.This study has policy implications for understanding the food security–climate nexus in the food production industry.展开更多
Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the ...Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the length to width, stem girth, dates of budding, leaf yield and ratio of the prime-medium tobacco. The leaf number and the central leaf length showed a positive or a strong positive correlation with the yield per plant. And the leaf number and leaf yield per plant showed a strong positive correlation with the ratio of prime-medium tobacco. The results showed that the leaf yield per plant among these characteristics played a major role in determining the ratio of prime-medium tobacco while the others were less related with the ratio. Square sum of deviation method cluster analyses showed that 24 pure lines of flue-cured tobacco were clustered into two groups. Of the pure lines, Line T1706 and Line T1245 had a far relationship with all other lines, and also had a heterosis when crossed with the other lines. Lines Guangdonghuang 1 and R72(3)B-2-1 were closely related.展开更多
Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were d...Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were divided into overcast, cloudy, and sunny conditions. On the half-hourly timescale, the daytime NEP responded more rapidly to the changes in the total photosynthetic active radiation(PARt) under overcast and cloudy skies than that under sunny skies. The increase in the apparent quantum yield under overcast and cloudy conditions was the greatest in spring and the least in summer. Additionally, lower atmospheric vapor pressure deficit(VPD) and moderate air temperature were more conducive to enhancing the apparent quantum yield under cloudy skies. On the daily timescale, NEP and the gross primary production(GPP) were higher under cloudy or sunny conditions than those under overcast conditions across seasons. The daily NEP and GPP during the wet season peaked under cloudy skies. The daily ecosystem light use efficiency(LUE) and water use efficiency(WUE) during the wet season also changed with sky conditions and reached their maximum under overcast and cloudy skies, respectively. The diffuse photosynthetic active radiation(PAR_d) and air temperature were primarily responsible for the variation of daily NEP from half-hourly to monthly timescales, and the direct photosynthetic active radiation(PAR_b) had a secondary effect on NEP. Under sunny conditions, PAR_b and air temperature were the dominant factors controlling daily NEP. While daily NEP was mainly controlled by PAR_d under cloudy and overcast conditions.展开更多
The Qilian Mountains(QM)possess a delicate vegetation ecosystem,amplifying the evident response of vegetation phenology to climate change.The relationship between changes in vegetation growth and climate remains compl...The Qilian Mountains(QM)possess a delicate vegetation ecosystem,amplifying the evident response of vegetation phenology to climate change.The relationship between changes in vegetation growth and climate remains complex.To this end,we used MODIS NDVI data to extract the phenological parameters of the vegetation including meadow(MDW),grassland(GSD),and alpine vegetation(ALV))in the QM from 2002 to 2021.Then,we employed path analysis to reveal the direct and indirect impacts of seasonal climate change on vegetation phenology.Additionally,we decomposed the vegetation phenology in a time series using the trigonometric seasonality,Box-Cox transformation,ARMA errors,and Trend Seasonal components model(TBATS).The findings showed a distinct pattern in the vegetation phenology of the QM,characterized by a progressive shift towards an earlier start of the growing season(SOS),a delayed end of the growing season(EOS),and an extended length of the growing season(LOS).The growth cycle of MDW,GSD,and ALV in the QM species is clearly defined.The SOS for MDW and GSD occurred earlier,mainly between late April and August,while the SOS for ALVs occurred between mid-May and mid-August,a one-month delay compared to the other vegetation.The EOS in MDW and GSD were concentrated between late August and April and early September and early January,respectively.Vegetation phenology exhibits distinct responses to seasonal temperature and precipitation patterns.The advancement and delay of SOS were mainly influenced by the direct effect of spring temperatures and precipitation,which affected 19.59%and 22.17%of the study area,respectively.The advancement and delay of EOS were mainly influenced by the direct effect of fall temperatures and precipitation,which affected 30.18%and 21.17%of the area,respectively.On the contrary,the direct effects of temperature and precipitation in summer and winter on vegetation phenology seem less noticeable and were mainly influenced by indirect effects.The indirect effect of winter precipitation is the main factor affecting the advance or delay of SOS,and the area proportions were 16.29%and 23.42%,respectively.The indirect effects of fall temperatures and precipitation were the main factors affecting the delay and advancement of EOS,respectively,with an area share of 15.80%and 21.60%.This study provides valuable insight into the relationship between vegetation phenology and climate change,which can be of great practical value for the ecological protection of the Qinghai-Tibetan Plateau as well as for the development of GSD ecological animal husbandry in the QM alpine pastoral area.展开更多
Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivati...Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivation of enhanced hybrid plants with desired traits,such as high yield and fine fiber quality.In this study,the general combining ability(GCA)and specific combining ability(SCA)of yield and fiber quality of nine cotton parents(six lines and three testers)and eighteen F1 crosses produced using a line×tester mating design were analyzed.Results The results revealed significant effects of genotypes,parents,crosses,and interactions between parents and crosses for most of the studied traits.Moreover,the effects of both additive and non-additive gene actions played a notably significant role in the inheritance of most of the yield and fiber quality attributes.The F1 hybrids of(Giza 90×Aust)×Giza 86,Uzbekistan 1×Giza 97,and Giza 96×Giza 97 demonstrated superior performance due to their favorable integration of high yield attributes and premium fiber quality characteristics.Path analysis revealed that lint yield has the highest positive direct effect on seed cotton yield,while lint percentage showed the highest negative direct effect on seed cotton yield.Principal component analysis identified specific parents and hybrids associated with higher cotton yield,fiber quality,and other agronomic traits.Conclusion This study provides insights into identifying potential single-and three-way cross hybrids with superior cotton yield and fiber quality characteristics,laying a foundation for future research on improving fiber quality in cotton.展开更多
文摘With China’s economic development entering a new normal,high-quality regional economic development has become an important goal of current economic development.As one of the important means to promote high-quality development of the regional economy,industrial policies are increasingly receiving attention in terms of their role and impact.This article mainly conducts an in-depth analysis of the mechanism and impact path of industrial policies,exploring the role and impact of industrial policies in promoting high-quality regional economic development.Firstly,industrial policies play an important role in promoting high-quality regional economic development.Secondly,the impact path of industrial policies on the high-quality development of the regional economy mainly includes promoting industrial structure upgrading,promoting technological innovation,guiding resource allocation,and enhancing enterprise competitiveness.Therefore,it is necessary to increase research and practice on industrial policies,continuously optimize policy measures,and promote high-quality development of the regional economy.
基金Jiangsu Province Philosophy and Social Sciences General Project"Exploration of the Path for Cultivating Innovation and Entrepreneurship Ability of Employment-Oriented Applied Undergraduate Talents"。
文摘The“one-stop”student community provides new support for innovation and entrepreneurship education in universities.Integrating innovation and entrepreneurship education into the“one-stop”student community work enriches course materials,integrates teacher resources,improves students’participation in innovation and entrepreneurship,and solves problems such as low student participation,lack of course resources,insufficient teacher resources,and single evaluation methods in traditional classrooms.Through various means such as exploring course resources,innovating management models,and strengthening team construction,the role of“one-stop”student communities in innovation and entrepreneurship education has been fully utilized,promoting the development of innovation and entrepreneurship education.
基金supported by the National Natural Sciences Foundation of China (40871027)the Initial Project of State Key Basic R & D Program of China (2009CB426309)the Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-YW-334)
文摘Runoff formation is a complex meteorological-hydrological process impacted by many factors,especially in the inland river basin.Based on the data of daily mean air temperature,precipitation and runoff during the period of 1958-2007 in the Kaidu River watershed,this paper analyzed the changes in air temperature,precipitation and runoff and revealed the direct and indirect impacts of daily air temperature and precipitation on daily runoff by path analysis.The results showed that mean temperature time series of the annual,summer and autumn had a significant fluctuant increase during the last 50 years(P 0.05).Only winter precipitation increased significantly(P 0.05) with a rate of 1.337 mm/10a.The annual and winter runoff depthes in the last 50 years significantly increased with the rates of 7.11 mm/10a and 1.85 mm/10a,respectively.The driving function of both daily temperature and precipitation on daily runoff in annual and seasonal levels is significant in the Kaidu River watershed by correlation analysis.The result of path analysis showed that the positive effect of daily air temperature on daily runoff depth is much higher than that of daily precipitation in annual,spring,autumn and winter,however,the trend is opposite in summer.
基金Supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of China(2015BAD07B04)Key Science and Technology Program of Henan Province,China(152102110059)
文摘Effects of environmental factors such as climate,topography,vegetation and soil in shelter forests in Three Gorges Reservoir Region on runoff and sediment yields were monitored to identify dominant environmental factors controlling runoff and sediment yields in 15 runoff plots in study area by soil sampling,laboratory analysis,stepwise regression analysis and path analysis,and to establish the main control environmental factors that affect runoff and sediment yields. The results showed that soil bulk density,herbaceous cover,slope,and canopy density were the significant factors controlling runoff,and the direct path coefficient of each factor was ranked as canopy closure(-0. 628) > litter thickness(-0. 547) > bulk density( 0. 509) > altitude( 0. 289). The indirect path coefficient was ranked as soil bulk density( 0. 354) >litter thickness(-0. 169) > altitude( 0. 126) > canopy closure(-0. 104). Therefore,canopy closure and litter thickness mainly had direct effects on runoff,while soil bulk density mainly had indirect effects through their contributions to other factors. Herbaceous cover,litter thickness,slope,canopy density,and altitude were the significant factors controlling sediment yields. The direct path coefficient of each factor was ranked as herbaceous cover(-0. 815) > litter thickness(-0. 777) > canopy closure(-0. 624) > slope( 0. 620). The indirect path coefficient was ranked as slope( 0. 272) > litter thickness(-0. 131) > canopy closure(-0. 097) > herbaceous cover(-0. 084). Therefore,herbaceous cover and litter thickness mainly had direct effects on sediment yields,while slope mainly had indirect effects through their contributions to other factors. All the selected environmental factors jointly explained 85. 5% and 78. 3% of runoff and sediment yield variability,respectively. However,there were large values of remaining path coefficients of other factors influencing runoff and sediment yields,which indicated that some important factors are not included and should be taken into account.
文摘In the paper presented, 99 single seed descent barley lines as well as their parental forms Roland and Apex were studied. The grain weight components and their interrelations were analyzed using simple coefficients of correlation. The direct and indirect effects of such components on grain weight per plant and 1 000-grain weight were estimated using path analysis. In the 2006 and 2007, the spike length and number of spikelets per spike were the determinants of grain weight. Genetic parameters as additive and epistasis effects were estimated for all studied traits. The results indicate the importance of both additive and epistasis gene effects of number of spikes per plant, grain weight per spike, grain number per plant and grain weight per plant in this study.
基金funded by the Open Foundation for the University Innovation Platform in the Hunan Province,grant number 18K103Open project,Grant Number 20181901CRP03,20181901CRP04,20181901CRP05+1 种基金Hunan Provincial Education Science 13th Five-Year Plan(Grant No.XJK016BXX001),Social Science Foundation of Hunan Province(Grant No.17YBA049)supported by the project 18K103。
文摘With the rapid development of science and technology and the increasing popularity of the Internet,the number of network users is gradually expanding,and the behavior of network users is becoming more and more complex.Users’actual demand for resources on the network application platform is closely related to their historical behavior records.Therefore,it is very important to analyze the user behavior path conversion rate.Therefore,this paper analyses and studies user behavior path based on sales data.Through analyzing the user quality of the website as well as the user’s repurchase rate,repurchase rate and retention rate in the website,we can get some user habits and use the data to guide the website optimization.
基金This work was supported by Guizhou Provincial Basic Research Program(Natural Science),Grant Number Qiankehejichu-ZK[2021]YB133Guizhou Provincial Scientific and Technological Program,Grant Number Qiankehehoubuzhu[2020]3001National Natural Science Foundation of China-Guizhou Provincial People’s Government Karst Science Research Centre(U1612442).
文摘The contents of carbon(C),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant significantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and caffeine.However,few studies have quantified the effects of these factors on the main quality components of tea.The study aimed to explore the interactions of C,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis method.The results indicated that(1)The contents of C,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed significant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on C,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBC)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,respectively.Leaf carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,respectively.Leaf carbon indirectly affected tea polyphenol content mainly by altering MBP content.Root phosphorus indirectly affected catechin content mainly by altering soil organic carbon content.Leaf nitrogen indirectly affected water extract content mainly by altering branch nitrogen content.The research results provide the scientific basis for reasonable fertilization in tea gardens and tea quality improvement.
基金supported by grants from the“3315”Innovative Team of Ningbo City,the Science and Technology Planning Project of Ningbo City(2021S009).
文摘Kumamoto oysters(Crassostrea sikamea)are important marine aquaculture shellfish because of their taste and round shell shape.Due to its small size,selective breeding is required to improve its market size,but there are no reports on traits suitable for direction selection and reproductive productivity of Kumamoto oysters of different ages.In this study,path analysis and one-way ANOVA were used to explore the influential indices of oyster body weight and fecundity.The results showed that shell height was the main factor affecting the body weight of Kumamoto oysters at one-year-old and two-year-old,followed by shell length.Body weight was the main factor influencing fecundity,and shell height showed a significant correlation with fecundity.Therefore,shell height should be considered the first parameter for selection when selecting Kumamoto oysters for body weight as the direct selection target.When one-year-old and two-year-old Kumamoto oysters were selected as parents from Xiangshan Bay,hatching parameters and growth parameters of F1 generation larvae were measured.The fecundity and egg diameters were 1.72×10^(6)and 46.60±3.62μm,respectively,which were significantly greater than one-aged oysters(5.86×10^(5),40.26±3.52μm).The hatching parameters(fertilized egg size,fertilization rate,and hatching rate)and larval growth performance(D-stage veliger and veliger)were similar and did not differ significantly(P>0.05),and after metamorphosis,there was also no significant difference in shell height size at 40 days of age(P>0.05).Therefore,there was no significant effect of age on reproduction,larval development,and the early growth of Kumamoto oysters.These results could provide a basis for parental sources and proper traits for Kumamoto oyster selection,which is beneficial to developing and utilizing this excellent germplasm resource.
文摘This study links social capital with people’s health and well-being using data from the seventh wave of the World Value Survey,logistic regression,and path analysis.The study’s findings show that happiness and life satisfaction are two different measures of the same construct,or well-being.The determinants of each are also characterised differently:while life satisfaction is more of a stable and relative measure and is more strongly influenced by civic cooperation,social participation,and educational attainment,happiness is more of an unstable measure and is more strongly influenced by community belonging,trust and confidence aggregates,including employment and location of residence of an individual.Moreover,freedom of choice,financial satisfaction or social comparison,and state of health were the most important factors influencing happiness and life satisfaction.The findings also show that self-reported health(SRH)has a greater impact on happiness than a measure of life satisfaction.Path analysis shows out of the three other components of social capital—community belonging,civic engagement,and social participation—trust and confidence aggregates are the ones that have the biggest impact on increased social capital.For both well-being measures,SRH mediated the relationship.The life satisfaction measure had a higher level of mediation of SRH than happiness,but social capital had a smaller direct impact on life satisfaction than on happiness.SRH was found to be partially mediating this relationship for both happiness and life satisfaction measures,which means that people with higher social capital reported feeling better off.
基金the National Natural Science Foundation of China(Grant No.52270154)the National Engineering Research Center for Bioenergy,Harbin Institute of Technology,China(Grant No.2021C001).
文摘Cadmium(Cd)contamination in rice has been a serious threat to human health.To investigate the effects of arbuscular mycorrhizal fungi(AMF)on the Cd translocation in rice,a controlled pot experiment was conducted.The results indicated that AMF significantly increased rice biomass,with an increase of up to 40.0%,particularly in root biomass by up to 68.4%.Notably,the number of prominent rice individuals also increased,and their plasticity was enhanced following AMF inoculation.AMF led to an increase in the net photosynthetic rate and antioxidant enzyme activity of rice.In the AMF treatment group,the Cd concentration in the rice roots was significantly higher(19.1%‒68.0%)compared with that in the control group.Conversely,the Cd concentration in the rice seeds was lower in the AMF treatment group,indicating that AMF facilitated the sequestration of Cd in rice roots and reduced Cd accumulation in the seeds.Path coefficients varied across different treatments,suggesting that AMF inoculation reduced the direct impact of soil Cd concentration on the total Cd accumulation in seeds.The translocation of Cd was consistently associated with simultaneous growth dilution and compensatory accumulation as a result of mycorrhizal effects.Our study quantitatively analyzed this process through path analysis and clarified the causal relationship between rice growth and Cd transfer under the influence of AMF.
基金the National Natural Science Foundation of China(No.51279059)supported by the program of“the Fundamental Research Funds for the Central Universities”(2015B14714)the project of“the Priority Academic Program Development of Jiangsu Higher Education Institutions”and“Jiang Su Qing Lan”.
文摘The physiological characters and growth of tomato(Solanum lycopersicum L.)were recorded to be largely affected by different levels of irrigation.The objectives of this research were to determine the effects of deficit irrigation and rain shelters on sap flow,relative water content and the relationship between sap flow and environmental parameters.Experiments under rain shelters conditions were conducted in southern China during the growing seasons in 2012.The threshold of irrigation was designed at 80%field capacity during the whole period(T1,the control),and 30%,40%and 50%decreased water of T1 were applied as the treatments of T2,T3 and T4.The plants subjected to water stress exhibited a decrease in the values of sap flow rate and relative water content.Calculation of 95%confidence level revealed a significant difference of sap flow rate in T4 and T3 as well as the control on sunny and rainy days.The diurnal variation of the sap flow showed a single peak curve on sunny day,while it demonstrated irregular multi-peak variation on rainy days.The study also showed that the most sensitive environmental indicator affecting sap flow was solar radiation,followed by air temperature and vapour pressure deficit.Direct path coefficient was basically consistent with the coefficient of correlation,but there was slight difference between the total contribution R2 and that of variable factors.
文摘Background Tuberculosis(TB)is one of the top 10 causes of death in the world.Since Directly Observed Therapy(DOT)as a core strategy for the global TB control are not applicable to all types of TB patients,and self-management of TB patients(SMTP)as a patient-centered supervision type is a supplement to DOT and can improve TB case management.However,the factors related to SMTP are complex and need more study.This study aimed at identifying the determinants of SMTP and examining the direct/indirect effects of these determinants.Methods The purposive sampling technique was used to select study sites and participants were recruited from the study sites by the consecutive sampling method.The PRECEDE model was used as the framework to analyze the determinants of SMTP.The responses of TB patients were acquired via a questionnaire survey for data collection.A Pearson correlation analysis was used to define the relationship between the predisposing,enabling,reinforcing factors with SMTP behaviors.A regression-based path analysis was used to determine the action paths of the predisposing,enabling,and reinforcing factors on SMTP behaviors.Results The predisposing(TB knowledge),enabling[health education and healthcare workers(HCWs)support],reinforcing factors(family support)had significant positive correlations with SMTP behaviors(P<0.05).The predisposing,enabling,reinforcing factors were positively correlated with each other(r=0.123‒0.918,P<0.05),except for family support and HCWs support.The predisposing factors(TB knowledge,β=0.330)and the enabling factors(HCWs support,β=0.437)had direct effects on SMTP behaviors.The enabling factors(health education and HCWs support)and the reinforcing factors(family support)had indirect effects on SMTP behaviors.Conclusions This study revealed the effects and action path of TB knowledge,health education,HCWs support,and family support on SMTP behaviors via a path analysis.Assessing patient’s needs for SMTP along with promoting effective TB health education and providing firm support from HCWs and family members are potential strategies to promote SMTP behaviors.
文摘The objective of this study was to determine the relationship between PM10 and PM2.5 levels as related to meteorological conditions and traffic flow using both a linear regression analysis and a path analysis. The Particulate matter(PM) samples were collected from Sukhumvit road, Bangkok, Thailand, at both open(104 samples) and covered(92 samples)areas along the road. Fifteen percent of all samples were separated before the statistical models were run and used for model validation. The results from the path analysis were more elaborate than those from the linear regression, thus indicating that meteorological conditions had a direct effect on the particulate levels and that the effects of traffic flow were more variable in open areas. The model also indicated that meteorological conditions had an indirect effect and that traffic flow had a direct effect on particulate levels in covered areas. The model validation results indicated that for open areas, the R^2 values were not very different between the path analysis and the linear regression model, but that the path analysis was more accurate than the linear regression model at very low PM concentrations. At high PM concentrations, the path analysis model also had a better fit than did the linear regression, so the predictions from the path analysis model were more accurate than those from the linear regression.
基金the financial support by the Natural Science Foundation of Zhejiang Province(No.LQ20G010001)China Postdoctoral Science Foundation(2020M673195)National Natural Science Foundation of China(No.71671165).
文摘Purpose-The purpose of this article is to conduct a main path analysis of 627 articles on the theme of Pythagorean fuzzy sets(PFSs)in the Web of Science(WoS)from 2013 to 2020,to provide a conclusive and comprehensive analysis for researchers in this field,and to provide a study on preliminary understanding of PFSs.Design/methodology/approach-The research topic of Pythagorean fuzzy fields,through keyword extraction and describing the changes in characteristic themes over the past eight years,are firstly examined.Main path analysis,including local and global main paths and key route paths,is then used to reveal the most influential relationships between papers and to explore the trajectory and structure of knowledge transmission.Findings-The application of Pythagorean fuzzy theory to the field of decision-making has been popular,and combinations of the traditional Pythagorean fuzzy decision-making method with other fuzzy sets have attracted widespread attention in recent years.In addition,over the past eight years,research interest has shifted to different types of PFSs,such as interval-valued PFSs.Research limitations/implications-This paper implicates to investigate the growth in certain trends in the literature and to explore the main paths of knowledge dissemination in the domain of PFSs in recent years.Originality/value-This paper aims to identify the topics in which researchers are currently interested,to help scholars to keep abreast of the latest research on PFSs.
文摘Geospatial technology is a useful tool when identifying land corridors for transportation networks. The primary transit corridor between Los Angeles, CA and Las Vegas, NV is Interstate-15, approximately a four-hour automobile trip without traffic. Virgin Trains USA LLC proposes an alternative means of travel by constructing a high-speed railway along Interstate-15 connecting Las Vegas and Victorville, CA. This study uses least-cost path analysis to propose an optimized alternative corridor for Virgin Trains’ proposed high-speed railway through a system facilitated road and rail accessibility analysis. Previous research using least-cost path and accessibility methodologies evaluated the results of proposed high-speed railway corridors and the system facilitated accessibility changes by visually inspecting deviations from a planned corridor using single or multiple cost criteria as inputs for a weighted cost surface. However, robust analyses of previous least-cost path studies’ corridors are lacking. This proof-in-concept study proposes a less costly corridor through least-cost path analysis and measures the social impact on the stakeholders of a high-speed railway transportation system through system facilitated accessibility. This study’s proposed alternative corridor is 31% shorter than Virgin Trains’ planned corridor and system facilitated accessibility to Las Vegas, NV is increased in 99.74% of Los Angeles County’s census tracts. These results support this study’s position that geospatial technology can support transportation planning in a comprehensive method that considers the transportation corridor and benefits its stakeholders.
基金financially supported by the Key Research and Development Program of Joint Research and Development Project Under the Sino–Thai Joint Committee on Science and Technology Cooperation(2017YFE0133000)the National Natural Science Foundation of China(72104239)+1 种基金the Fundamental Research Funds for Central Public Welfare Research Institutes,China(Y2022ZK03)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciences(ASTIP-IAED-2022-04)。
文摘Irrigated agriculture has tripled since 1950,accounting for 20%of the global arable land and 40%of food production.Irrigated agriculture increases food security yet has controversial implications for global climate change.Most previous studies have calculated carbon emissions and their composition in irrigated areas using the engineering approach to life-cycle assessment.By combining life cycle assessment(LCA)-based carbon emissions accounting with econometric models such as multiple linear regression and structural equation modeling(SEM),we conducted an interdisciplinary study to identify the influencing factors and internal mechanisms of the carbon footprint(CFP)of smallholder crop cultivation on irrigation reform pilot areas.To this end,we investigated corn and potato production data in the 2019–2020 crop years for 852 plots of 345 rural households in six villages(two irrigation agriculture pilot villages and four surrounding villages as controls)in Southwest China.The crop CFP in the irrigation agriculture pilot areas was significantly lower than in non-reform areas.Irrigation reforms mainly impacted the crop CFP through four intermediary effects:the project(implementation of field irrigation channels),technology(improving adoption of new irrigation technologies),management(proper irrigation operation and maintenance),and yield effects.All effects inhibited the CFP,except for the project effect that promotes carbon emissions.Among them,yield increase has the greatest impact on reducing CFP,followed by management and technology effects.Furthermore,planting practices,individual characteristics,and plot quality significantly impacted the crop CFP.This study has policy implications for understanding the food security–climate nexus in the food production industry.
基金Supported by Platform Construction for Germplasm Resources of China Tobacco (2007, 152)
文摘Correlation and path coefficient analyses were conducted for 10 characteristics of 24 pure lines of flue-cured tobacco such as plant height, knot distance, leaf number, the central leaf length and width, ratio of the length to width, stem girth, dates of budding, leaf yield and ratio of the prime-medium tobacco. The leaf number and the central leaf length showed a positive or a strong positive correlation with the yield per plant. And the leaf number and leaf yield per plant showed a strong positive correlation with the ratio of prime-medium tobacco. The results showed that the leaf yield per plant among these characteristics played a major role in determining the ratio of prime-medium tobacco while the others were less related with the ratio. Square sum of deviation method cluster analyses showed that 24 pure lines of flue-cured tobacco were clustered into two groups. Of the pure lines, Line T1706 and Line T1245 had a far relationship with all other lines, and also had a heterosis when crossed with the other lines. Lines Guangdonghuang 1 and R72(3)B-2-1 were closely related.
基金funded by the National Natural Science Foundation of China (Grant No. 91937301)the Second Tibetan Plateau Scientific Expedition and Research (STEP) program (Grant No. 2019QZKK0105)the National Natural Science Foundation of China (Grant Nos. 41975017, 41905010)。
文摘Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were divided into overcast, cloudy, and sunny conditions. On the half-hourly timescale, the daytime NEP responded more rapidly to the changes in the total photosynthetic active radiation(PARt) under overcast and cloudy skies than that under sunny skies. The increase in the apparent quantum yield under overcast and cloudy conditions was the greatest in spring and the least in summer. Additionally, lower atmospheric vapor pressure deficit(VPD) and moderate air temperature were more conducive to enhancing the apparent quantum yield under cloudy skies. On the daily timescale, NEP and the gross primary production(GPP) were higher under cloudy or sunny conditions than those under overcast conditions across seasons. The daily NEP and GPP during the wet season peaked under cloudy skies. The daily ecosystem light use efficiency(LUE) and water use efficiency(WUE) during the wet season also changed with sky conditions and reached their maximum under overcast and cloudy skies, respectively. The diffuse photosynthetic active radiation(PAR_d) and air temperature were primarily responsible for the variation of daily NEP from half-hourly to monthly timescales, and the direct photosynthetic active radiation(PAR_b) had a secondary effect on NEP. Under sunny conditions, PAR_b and air temperature were the dominant factors controlling daily NEP. While daily NEP was mainly controlled by PAR_d under cloudy and overcast conditions.
基金financially supported by the National Natural Sciences Foundation of China(42261026,41971094,and 42161025)Gansu Science and Technology Research Project(22ZD6FA005)+1 种基金Higher Education Innovation Foundation of Education Department of Gansu Province(2022A-041)the open foundation of Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone(XJYS0907-2023-01).
文摘The Qilian Mountains(QM)possess a delicate vegetation ecosystem,amplifying the evident response of vegetation phenology to climate change.The relationship between changes in vegetation growth and climate remains complex.To this end,we used MODIS NDVI data to extract the phenological parameters of the vegetation including meadow(MDW),grassland(GSD),and alpine vegetation(ALV))in the QM from 2002 to 2021.Then,we employed path analysis to reveal the direct and indirect impacts of seasonal climate change on vegetation phenology.Additionally,we decomposed the vegetation phenology in a time series using the trigonometric seasonality,Box-Cox transformation,ARMA errors,and Trend Seasonal components model(TBATS).The findings showed a distinct pattern in the vegetation phenology of the QM,characterized by a progressive shift towards an earlier start of the growing season(SOS),a delayed end of the growing season(EOS),and an extended length of the growing season(LOS).The growth cycle of MDW,GSD,and ALV in the QM species is clearly defined.The SOS for MDW and GSD occurred earlier,mainly between late April and August,while the SOS for ALVs occurred between mid-May and mid-August,a one-month delay compared to the other vegetation.The EOS in MDW and GSD were concentrated between late August and April and early September and early January,respectively.Vegetation phenology exhibits distinct responses to seasonal temperature and precipitation patterns.The advancement and delay of SOS were mainly influenced by the direct effect of spring temperatures and precipitation,which affected 19.59%and 22.17%of the study area,respectively.The advancement and delay of EOS were mainly influenced by the direct effect of fall temperatures and precipitation,which affected 30.18%and 21.17%of the area,respectively.On the contrary,the direct effects of temperature and precipitation in summer and winter on vegetation phenology seem less noticeable and were mainly influenced by indirect effects.The indirect effect of winter precipitation is the main factor affecting the advance or delay of SOS,and the area proportions were 16.29%and 23.42%,respectively.The indirect effects of fall temperatures and precipitation were the main factors affecting the delay and advancement of EOS,respectively,with an area share of 15.80%and 21.60%.This study provides valuable insight into the relationship between vegetation phenology and climate change,which can be of great practical value for the ecological protection of the Qinghai-Tibetan Plateau as well as for the development of GSD ecological animal husbandry in the QM alpine pastoral area.
文摘Background As the most widely cultivated fiber crop,cotton production depends on hybridization to unlock the yield potential of current varieties.A deep understanding of genetic dissection is crucial for the cultivation of enhanced hybrid plants with desired traits,such as high yield and fine fiber quality.In this study,the general combining ability(GCA)and specific combining ability(SCA)of yield and fiber quality of nine cotton parents(six lines and three testers)and eighteen F1 crosses produced using a line×tester mating design were analyzed.Results The results revealed significant effects of genotypes,parents,crosses,and interactions between parents and crosses for most of the studied traits.Moreover,the effects of both additive and non-additive gene actions played a notably significant role in the inheritance of most of the yield and fiber quality attributes.The F1 hybrids of(Giza 90×Aust)×Giza 86,Uzbekistan 1×Giza 97,and Giza 96×Giza 97 demonstrated superior performance due to their favorable integration of high yield attributes and premium fiber quality characteristics.Path analysis revealed that lint yield has the highest positive direct effect on seed cotton yield,while lint percentage showed the highest negative direct effect on seed cotton yield.Principal component analysis identified specific parents and hybrids associated with higher cotton yield,fiber quality,and other agronomic traits.Conclusion This study provides insights into identifying potential single-and three-way cross hybrids with superior cotton yield and fiber quality characteristics,laying a foundation for future research on improving fiber quality in cotton.