Cashew tree has gradually moved from a purely ecological aspect to a socio-economic one, due to the marketing of its nuts. But production per area, estimated at between 424 and 547 kg/ha, remains low, in contrast to I...Cashew tree has gradually moved from a purely ecological aspect to a socio-economic one, due to the marketing of its nuts. But production per area, estimated at between 424 and 547 kg/ha, remains low, in contrast to India (2<sup>nd</sup> largest producer) and Vietnam (3<sup>rd</sup> largest producer), whose yields range from 1000 to 1500 and 2000 to 2500 kg/ha respectively. This low yield is due to a number of factors, among which insect pests are the most damaging. Among these insects, termites are considered to be one of the main pests of cashew trees. The general objective of this study is to contribute to termite management through the use of bioinsecticides, an alternative to the use of chemicals in cashew orchards. Five (5) biological products were tested: Limocide, Carapa oil, Neem oil, Kitana and Kaskara. Among them, two products proved effective, with a mortality rate of over 50%. These were Limocide, whose LC50 was obtained in 24 h at a dose of 3.6 g/ml and 3.1 g/ml , giving a mortality rate of 57.66% ± 4.04% and 51.33 ± 2.08 respectively , and Carapa, at a dose of 4.5 g/ml, with an estimated mortality rate of 52.33% ± 1.52%. Such results have demonstrated the potential application of Limocide and Carapa biopesticides to sustainably control termites in cashew orchards of Côte d’Ivoire.展开更多
Accurate prediction ofmonthly oil and gas production is essential for oil enterprises tomake reasonable production plans,avoid blind investment and realize sustainable development.Traditional oil well production trend...Accurate prediction ofmonthly oil and gas production is essential for oil enterprises tomake reasonable production plans,avoid blind investment and realize sustainable development.Traditional oil well production trend prediction methods are based on years of oil field production experience and expertise,and the application conditions are very demanding.With the rapid development of artificial intelligence technology,big data analysis methods are gradually applied in various sub-fields of the oil and gas reservoir development.Based on the data-driven artificial intelligence algorithmGradient BoostingDecision Tree(GBDT),this paper predicts the initial single-layer production by considering geological data,fluid PVT data and well data.The results show that the GBDT algorithm prediction model has great accuracy,significantly improving efficiency and strong universal applicability.The GBDTmethod trained in this paper can predict production,which is helpful for well site optimization,perforation layer optimization and engineering parameter optimization and has guiding significance for oilfield development.展开更多
Unbalanced agricultural production decision becomes the great block that influences the effective distribution of social resources, national grain security, social stability and economic development. This paper took t...Unbalanced agricultural production decision becomes the great block that influences the effective distribution of social resources, national grain security, social stability and economic development. This paper took the game theory as an analyzed tool to describe the interactional processes among the peasants, and set up the game theory model of independent decision and joint decision by peasants. It was shown that the government's positive guide and the market environment macroscopically controlled by the government could effectively increased the peasants' income展开更多
Even today,academics continue to debate the effect of feminization of agricultural labor force on agricultural output.By considering the dimensions of participation in decision-making and production,this study divides...Even today,academics continue to debate the effect of feminization of agricultural labor force on agricultural output.By considering the dimensions of participation in decision-making and production,this study divides the various agricultural production models into three types:(i)the traditional model of decisions made either jointly by men and women or by men alone while both genders participate in production,(ii)complete feminization of agricultural decision-making and the production labor force,and(iii)feminization of the agricultural production labor force only.This study investigates the effects of combining or separating decision-making and production in regard to agricultural development in the context of feminization of the agricultural labor force.Using follow-up data collected from 2004–2008 by the Ministry of Agriculture of China,we built a comprehensive panel data model to test our hypotheses.Our research shows that in comparison to traditional agricultural households and fully feminized agricultural labor forces,partially feminized production resulted in lower grain yield and technological advancement.The feminization of agricultural labor does not necessarily have a negative impact on agricultural output,especially since heavy manual labor is being increasingly replaced by agricultural machinery and outsourcing of tasks.The degree of feminization of the decision-making and production processes should be an important consideration when evaluating the purported negative effects of the feminization of agricultural labor.展开更多
Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in China has two different chains, the chief-engineer chain an...Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in China has two different chains, the chief-engineer chain and the general-director chain,to handle the trade-off between technical and management decisions. However, previous works on organization search have mainly focused on the single-chain hierarchical organization in which all decisions are regarded as homogeneous. The heterogeneity and the interdependency between technical decisions and management decisions have been neglected. A two-chain hierarchical organization structure mapped from a real complex project is constructed. Then, a discrete decision model for a Liang Zong two-chain hierarchical organization in an NK model framework is proposed. This model proves that this kind of organization structure can reduce the search space by a large amount and that the search process should reach a final stable state more quickly. For a more complicated decision mechanism, a multi-agent simulation based on the above NK model is used to explore the effect of the two-chain organization structure on the speed, stability, and performance of the search process. The results provide three insights into how, compared with the single-chain hierarchical organization, the two-chain organization can improve the search process: it can reduce the number of iterations efficiently; the search is more stable because the search space is a smoother hill-like fitness landscape; in general, the search performance can be improved.However, when the organization structure is very complicated, the performance of a two-chain organization is inferior to that of a single-chain organization. These findings about the efficiency of the unique Chinese-style organization structure can be used to guide organization design for complex projects.展开更多
We summarize the main forms of tobacco production organization in Sichuan Province,including traditional peasant households,large scale growers,family farms,tobacco farmers' associations,and specialized tobacco co...We summarize the main forms of tobacco production organization in Sichuan Province,including traditional peasant households,large scale growers,family farms,tobacco farmers' associations,and specialized tobacco cooperatives.In the process of innovation of production organization mode,some problems are pointed out,such as lack of management talents and long-term incentive mechanism,lack of standardization in operation,bottleneck in land and financing,low economic benefits of cooperatives,and difficulty in protecting farmers' interests and rights.We put forth the following recommendations for advancing the innovation of tobacco production organization mode in Sichuan Province:forming the longterm mechanism for supporting the innovation of production organization forms;standardizing the operation of the specialized cooperative organizations;strengthening personnel training,and establishing tobacco farmers' principal position;expanding cooperative economic production organizations,and achieving moderate concentration of land size;strengthening information services,to boost the development of cooperative production organizations.展开更多
The purpose of this paper was to examine the role of quantitative analysis in production planning decisions. This draws from the observed imperatives of quantitative analysis in business decisions and its capacity for...The purpose of this paper was to examine the role of quantitative analysis in production planning decisions. This draws from the observed imperatives of quantitative analysis in business decisions and its capacity for predictability and enhanced decision making given the increasingly complex nature of the business environment. The paper therefore addressed the historical evolution of quantitative technique as an efficient and effective decision-making tool. The content of the paper addressed commonly applied quantitative technique in manufacturing firms today which is, linear programming and its subsequent impact on production planning decisions. The results based on a congruence of views revealed that the “best-fit” application of quantitative analysis models and tools can untangle the complexities of production and planning decision making process in order to achieve the organizational goal. This is, as literature also showed that there is obviously no consensus or integrated model that is capable of solving all managerial problem, different models such as the linear programming model have however been developed to cater for different problems as they arise. The workability or suitability of quantitative analysis is actually premised on its appropriate application. The paper recommends the application of quantitative analysis using linear programming in solving various resource allocation related issues in the primary production planning function of manufacturing firms.展开更多
The presence of acidic soil in rural areas poses difficulties for agricultural production.One factor regulating soil pH is the overuse of inorganic fertilizer.The increased use of fertilizers in soybean production not...The presence of acidic soil in rural areas poses difficulties for agricultural production.One factor regulating soil pH is the overuse of inorganic fertilizer.The increased use of fertilizers in soybean production not only raises sustainability concerns but also contributes to soil acidity.Therefore,the use of organic fertilizer could offer a solution for addressing both issues related to soil acidity and sustainability.The purpose of this study was to investigate the manipulation of soil pH using organic fertilizer for soybean production under acidic stress.The planting medium,consisting of a mixture of topsoil,rice husk charcoal,and organic fertilizer(in a ratio of 2:1:1),was supplemented with 0.5 g of NPK fertilizer as a basal treatment in each planting medium.To regulate the soil acidity to pH 4,we added FeSO_(4) and allowed the mixture to incubate for 30 days.The results demonstrate that the application of three types of organic fertilizers chicken manure(P1),oil palm empty bunch fertilizer(P2),and vermicompost(P3)positively impacts the growth of three soybean varieties.The findings indicate that the application of P2 organic fertilizer can increase vegetative growth almost 50%in soybeans on acidic soil,including plant height,leaf count,and root length.Meanwhile,applying P3 organic fertilizer can boost reproductive growth responses in soybeans on acidic soil,such as pod number(from around 0-4 unit to 42-51 unit),grain number(from around 0-5 unit to 88-90 unit),and grain weight(from around 0-0.37 g to 12-25 g).Organic fertilizer has the potential to regulate soil pH,promoting higher yields of soybeans under acidic stress.展开更多
The lacustrine organic-rich shale in the Permian Lucaogou(LCG)Formation of the Jimsar Sag,Junggar Basin,is one of the main shale oil plays in China.In this paper,geological and geochemical research techniques were emp...The lacustrine organic-rich shale in the Permian Lucaogou(LCG)Formation of the Jimsar Sag,Junggar Basin,is one of the main shale oil plays in China.In this paper,geological and geochemical research techniques were employed to evaluate the geochemical variability of the lacustrine shale and the pro-duction of organic matter and its preservation conditions.The LcG Formation is characterized by its complex mineral compositions and a wide range of organic matter richness and quality.The presence of high proportions ofβ-carotane and C2g steranes,indicates that the organic matter mainly originated from phytoplankton and aquatic algal-bacterial organisms,especially cyanobacteria.This study found that the productivity of the Lower LCG Member(P2li)was highest,and the Middle LCG Member(P_(2)l_(2))was the lowest.During the deposition of the Lower LCG Member,the lake's bottom water was predominantly a reducing environment,and the degradation of organic matter was largely a result of bacterial sulfate reduction.During the deposition of the Middle and Upper LCG members,the lake's bottom water was mainly oxidizing,and the degradation of organic matter was likely to be caused by aerobic processes.Based on a comprehensive analysis of the origin and production of organic matter,as well as its depo-sitional environment and preservation conditions,two organic matter accumulation models were pro-posed to explain the distribution of the organic-rich shale.In model A,the high influx of volcanic ash released nutrients and brought abundant sulfate into the water,the accumulation of organic matter was mainly controlled by the preservation of organic matter,which was mainly controlled by BsR.In the model B,the influx of volcanic ash was small,organic matter was mainly degraded by oxygen and the accumulation of organic matter is mainly determined by the production of organic matter.展开更多
The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeoche...The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeochemistry of DOP is in its infancy. In the present study, monthly data between 2000 and 2014 were used to analyze the temporal and spatial distributions of DOP in the Mir Bay, the northern South China Sea. The DOP residence time(TDOP) was also investigated using a simple regression analysis in combination with chlorophyll a(Chl a) measurements while excess DOP(ΔDOP), produced by the biogeochemical processes of autotrophic production and heterotrophic removal, was determined using a two-component mixing mass-balance model in combination with salinity measurements. The results showed that the DOP concentration was(0.017±0.010) mg/L higher in the surface-water compared with the bottom-water and higher in the inner Tolo Harbour and waters adjacent to Shatoujiao compared with the main zone of the bay. Although seasonal changes and annual variability in the DOP were small, the surface DOP concentration was higher in the wet season(April–September)than in the dry season(October–March) due to the impacts of seaward discharges and atmospheric deposition into the bay. Measurement and regression results showed that the DOP release rate from phytoplankton production was about 1.83(gP)/(gChl a) and the TDOP was about 7 d, which implied that the DOP cycle in the bay was rapid. The ΔDOP was calculated from the model to be about 0.000 mg/L in the main zone of the bay and about 0.002 mg/L in the inner Tolo Harbour and waters adjacent to Shaotoujiao, suggesting that the autotrophic production of DOP was almost balanced by the heterotrophic removal in the main zone of the bay and dominated in the inner Tolo Harbour and waters adjacent to Shaotoujiao. In conclusion, the Mirs Bay is very productive and fairly heterotrophic.展开更多
Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic...Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic value,NTFPs have faced the problem of over-exploitation,and the key to solve this problem is to determine the feasible way of sustainable utilization of NTFPs.Harvest intensity is one of the most important and easily controlled utilization factors,which can greatly influence the plant individual survival,growth and reproductive performances,and even the population structure and dynamics.Therefore,we chose two common and important NTFPs species with different marketable parts(i.e.,Acanthopanax senticosus with tender leaves and Aralia elata with tender buds)as our study objects.Aiming to determine the optimum harvest intensity for sustainably utilizing both NTFPs species,five levels of harvest intensity treatments(i.e.,control,light,medium,high and severe)were designed to assess the effects of harvest intensity on their marketable organ yield,plant growth and reproductive performances.Results:The biomass growth rates of marketable organ and plant growth of A.senticosus under light harvest intensity treatment were significantly higher than those under other harvest intensities.The plant height growth and 1000-seed weight of A.elata under severe harvest intensity treatment were significantly lower than those under control treatment.Conclusions:The light harvest intensity with 25% leaf removal and the high harvest intensity with all terminal buds harvested are the optimum harvest intensity to maintain the sustainable utilization of A.senticosus and A.elata,respectively.These findings could provide managers with basic but practical guidance for making decisions about the sustainable harvest management plan for the cultivated NTFPs species,and further provide a theoretical basis for managers to establish the harvest regulations for wild NTFPs species.Consequently,the local residents or communities can improve their income while ensure the sustainable development of wild NTFPs.展开更多
Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the a...Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters (AGP) has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. Numerous feed additives are in vogue for achieving this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are (3-4 weeks age) exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb's cycle and thus act as an energy source preventing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performance. It is concluded that organic acids and their salts increase the protein utilization especially in weaner pigs and improves production indices.展开更多
Paddy field is an important land use in subtropical China. Development of high soil fertility and productivity is the management goal of paddy field, Fertilization and management practices have not only influenced the...Paddy field is an important land use in subtropical China. Development of high soil fertility and productivity is the management goal of paddy field, Fertilization and management practices have not only influenced the status of organic matter and nutrients in the soil but also affected the environmental quality. This article investigates the contents of organic carbon and the nutrients, and the change over the last 20 years in highly productive paddy soils and their environmental application. Field soils were sampled and the analytical results were compared with the corresponding values in the Second Soil Survey in Yujiang County of Jiangxi Province, China. The results showed that surface soils at a depth of 0-10 cm in highly productive paddy fields in Yujiang County of Jiangxi Province had contents of organic carbon (20.2 ±3.88) g kg^-1, total nitrogen (2.09±0.55) g kg^-1, and available phosphorus (42.7 ±32.7) mg kg^-1, respectively, which were all at very rich levels. Over the last 20 years, the organic carbon pool of the highly productive paddy soils reached a steady state. Total N and available P significantly increased, whereas available K changed a little. The amount and percentage of P immobilization in the surface soil (0-10 cm) of highly productive paddy fields were (142.7 ~ 41.1) mg kg-~ and (36.2~ 10.4)% of added P, and CEC (7.93 ~ 1.32) cmol kg-~. These two parameters were not higher than the mean values of paddy soils and upland red soils in the areas. Results also showed that fertilizer P in highly productive paddy soils had a high mobility and was prone to move toward a water body, which is the main source of nutrients causing eutrophication. Because of a weak K-fixing capacity, the available K content was not high in highly productive paddy soils. This suggests that attention should be paid to the K balance and the increase of soil K pool.展开更多
Seafloor hydrothermal vent fields(SHVFs) are located in the mid-ocean ridge(MOR),backarc basin(BAB),island arc and hot-spot environments and hosted mainly by ultramafic,mafic,felsic rocks,and sediments.The hydrotherma...Seafloor hydrothermal vent fields(SHVFs) are located in the mid-ocean ridge(MOR),backarc basin(BAB),island arc and hot-spot environments and hosted mainly by ultramafic,mafic,felsic rocks,and sediments.The hydrothermal vent fluids of SHVFs have low oxygen,abnormal pH and temperature,numerous toxic compounds,and inorganic energy sources,such as sulfuric compounds,methane,and hydrogen.The geological,physical,and chemical characteristics of SHVFs provide important clues to understanding the formation and evolution of seafloor hydrothermal systems,leading to the determination of metal sources and the reconstruction of the physicochemical conditions of metallogenesis.Over the past two decades,we studied the geological settings,volcanic rocks,and hydrothermal products of SHVFs and drawn new conclusions in these areas,including:1) the hydrothermal plumes in the Okinawa Trough are affected by the Kuroshio current;2) S and Pb in the hydrothermal sulfides from MOR are mainly derived from their host igneous rocks;3) Re and Os of vent fluids are more likely to be incorporated into Fe-and Fe-Cu sulfide mineral facies,and Os is enriched under low-temperature(<200℃) hydrothermal conditions in global SHVFs;4) compared with low-temperature hydrothermal sulfides,sulfates,and opal minerals,high-temperature hydrothermal sulfides maintain the helium(He) isotopic composition of the primary vent fluid;5) relatively low temperature(<116℃),oxygenated,and acidic environment conditions are favorable for forming a native sulfur chimney,and a "glue pudding" growth model can be used to understand the origin of native sulfur balls in the Kueishantao hydrothermal field;and 6) boron isotope from hydrothermal plumes and fluids can be used to describe their diffusive processes.The monitoring and understanding of the physical structure,chemical composition,geological processes,and diverse organism of subseafloor hydrothermal systems will be a future hot spot and frontier of submarine hydrothermal geology.展开更多
Irrigation in lowland rice production systems in Sub-Saharan Africa (SSA) is mainly based on traditional surface irrigation methods with continuous flooding practices. This irrigation method ends up using a lot more w...Irrigation in lowland rice production systems in Sub-Saharan Africa (SSA) is mainly based on traditional surface irrigation methods with continuous flooding practices. This irrigation method ends up using a lot more water that would have otherwise been used to open more land and be used in other water-requiring sectors. Various studies suggest Alternate Wetting and Drying (AWD) as an alternative practice for water management that reduces water use without significantly affecting yield. However, this practice has not been well adopted by the farmers despite its significant benefits of reduced total water use. Improving the adoption of AWD using irrigation Decision Support Systems (DSSs) helps the farmer on two fronts;to know “how much water to apply” and “when to irrigate”, which is very critical in maximizing productivity. This paper reviews the applicability of DSSs using AWD in lowland rice production systems in Sub-Saharan Africa.展开更多
With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic...With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic of various circles of society. In order to accelerate the poverty alleviation and provide references and recommendations for further development of theory and practice of financial poverty alleviation,this paper made an overview of the organization system,operation mechanism and service products of rural financial poverty alleviation,elaborated the development path of financial poverty alleviation,and came up with recommendations for financial poverty alleviation.展开更多
文摘Cashew tree has gradually moved from a purely ecological aspect to a socio-economic one, due to the marketing of its nuts. But production per area, estimated at between 424 and 547 kg/ha, remains low, in contrast to India (2<sup>nd</sup> largest producer) and Vietnam (3<sup>rd</sup> largest producer), whose yields range from 1000 to 1500 and 2000 to 2500 kg/ha respectively. This low yield is due to a number of factors, among which insect pests are the most damaging. Among these insects, termites are considered to be one of the main pests of cashew trees. The general objective of this study is to contribute to termite management through the use of bioinsecticides, an alternative to the use of chemicals in cashew orchards. Five (5) biological products were tested: Limocide, Carapa oil, Neem oil, Kitana and Kaskara. Among them, two products proved effective, with a mortality rate of over 50%. These were Limocide, whose LC50 was obtained in 24 h at a dose of 3.6 g/ml and 3.1 g/ml , giving a mortality rate of 57.66% ± 4.04% and 51.33 ± 2.08 respectively , and Carapa, at a dose of 4.5 g/ml, with an estimated mortality rate of 52.33% ± 1.52%. Such results have demonstrated the potential application of Limocide and Carapa biopesticides to sustainably control termites in cashew orchards of Côte d’Ivoire.
文摘Accurate prediction ofmonthly oil and gas production is essential for oil enterprises tomake reasonable production plans,avoid blind investment and realize sustainable development.Traditional oil well production trend prediction methods are based on years of oil field production experience and expertise,and the application conditions are very demanding.With the rapid development of artificial intelligence technology,big data analysis methods are gradually applied in various sub-fields of the oil and gas reservoir development.Based on the data-driven artificial intelligence algorithmGradient BoostingDecision Tree(GBDT),this paper predicts the initial single-layer production by considering geological data,fluid PVT data and well data.The results show that the GBDT algorithm prediction model has great accuracy,significantly improving efficiency and strong universal applicability.The GBDTmethod trained in this paper can predict production,which is helpful for well site optimization,perforation layer optimization and engineering parameter optimization and has guiding significance for oilfield development.
文摘Unbalanced agricultural production decision becomes the great block that influences the effective distribution of social resources, national grain security, social stability and economic development. This paper took the game theory as an analyzed tool to describe the interactional processes among the peasants, and set up the game theory model of independent decision and joint decision by peasants. It was shown that the government's positive guide and the market environment macroscopically controlled by the government could effectively increased the peasants' income
基金supported by the the National Natural Science Foundation of China (71573133, 71673047 and 71473122)the Center for Food Security Research of Nanjing Agricultural Universitythe Center for Cooperative Innovation of Modern Grain Circulation and Security of Jiangsu Province, China
文摘Even today,academics continue to debate the effect of feminization of agricultural labor force on agricultural output.By considering the dimensions of participation in decision-making and production,this study divides the various agricultural production models into three types:(i)the traditional model of decisions made either jointly by men and women or by men alone while both genders participate in production,(ii)complete feminization of agricultural decision-making and the production labor force,and(iii)feminization of the agricultural production labor force only.This study investigates the effects of combining or separating decision-making and production in regard to agricultural development in the context of feminization of the agricultural labor force.Using follow-up data collected from 2004–2008 by the Ministry of Agriculture of China,we built a comprehensive panel data model to test our hypotheses.Our research shows that in comparison to traditional agricultural households and fully feminized agricultural labor forces,partially feminized production resulted in lower grain yield and technological advancement.The feminization of agricultural labor does not necessarily have a negative impact on agricultural output,especially since heavy manual labor is being increasingly replaced by agricultural machinery and outsourcing of tasks.The degree of feminization of the decision-making and production processes should be an important consideration when evaluating the purported negative effects of the feminization of agricultural labor.
基金supported by the National Natural Science Foundation of China(7157105771390522)the Key Lab for Public Engineering Audit of Jiangsu Province,Nanjing Audit University(GGSS2016-08)
文摘Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in China has two different chains, the chief-engineer chain and the general-director chain,to handle the trade-off between technical and management decisions. However, previous works on organization search have mainly focused on the single-chain hierarchical organization in which all decisions are regarded as homogeneous. The heterogeneity and the interdependency between technical decisions and management decisions have been neglected. A two-chain hierarchical organization structure mapped from a real complex project is constructed. Then, a discrete decision model for a Liang Zong two-chain hierarchical organization in an NK model framework is proposed. This model proves that this kind of organization structure can reduce the search space by a large amount and that the search process should reach a final stable state more quickly. For a more complicated decision mechanism, a multi-agent simulation based on the above NK model is used to explore the effect of the two-chain organization structure on the speed, stability, and performance of the search process. The results provide three insights into how, compared with the single-chain hierarchical organization, the two-chain organization can improve the search process: it can reduce the number of iterations efficiently; the search is more stable because the search space is a smoother hill-like fitness landscape; in general, the search performance can be improved.However, when the organization structure is very complicated, the performance of a two-chain organization is inferior to that of a single-chain organization. These findings about the efficiency of the unique Chinese-style organization structure can be used to guide organization design for complex projects.
基金Supported by Technology Project of Sichuan Tobacco Monopoly Administration (201102014)
文摘We summarize the main forms of tobacco production organization in Sichuan Province,including traditional peasant households,large scale growers,family farms,tobacco farmers' associations,and specialized tobacco cooperatives.In the process of innovation of production organization mode,some problems are pointed out,such as lack of management talents and long-term incentive mechanism,lack of standardization in operation,bottleneck in land and financing,low economic benefits of cooperatives,and difficulty in protecting farmers' interests and rights.We put forth the following recommendations for advancing the innovation of tobacco production organization mode in Sichuan Province:forming the longterm mechanism for supporting the innovation of production organization forms;standardizing the operation of the specialized cooperative organizations;strengthening personnel training,and establishing tobacco farmers' principal position;expanding cooperative economic production organizations,and achieving moderate concentration of land size;strengthening information services,to boost the development of cooperative production organizations.
文摘The purpose of this paper was to examine the role of quantitative analysis in production planning decisions. This draws from the observed imperatives of quantitative analysis in business decisions and its capacity for predictability and enhanced decision making given the increasingly complex nature of the business environment. The paper therefore addressed the historical evolution of quantitative technique as an efficient and effective decision-making tool. The content of the paper addressed commonly applied quantitative technique in manufacturing firms today which is, linear programming and its subsequent impact on production planning decisions. The results based on a congruence of views revealed that the “best-fit” application of quantitative analysis models and tools can untangle the complexities of production and planning decision making process in order to achieve the organizational goal. This is, as literature also showed that there is obviously no consensus or integrated model that is capable of solving all managerial problem, different models such as the linear programming model have however been developed to cater for different problems as they arise. The workability or suitability of quantitative analysis is actually premised on its appropriate application. The paper recommends the application of quantitative analysis using linear programming in solving various resource allocation related issues in the primary production planning function of manufacturing firms.
文摘The presence of acidic soil in rural areas poses difficulties for agricultural production.One factor regulating soil pH is the overuse of inorganic fertilizer.The increased use of fertilizers in soybean production not only raises sustainability concerns but also contributes to soil acidity.Therefore,the use of organic fertilizer could offer a solution for addressing both issues related to soil acidity and sustainability.The purpose of this study was to investigate the manipulation of soil pH using organic fertilizer for soybean production under acidic stress.The planting medium,consisting of a mixture of topsoil,rice husk charcoal,and organic fertilizer(in a ratio of 2:1:1),was supplemented with 0.5 g of NPK fertilizer as a basal treatment in each planting medium.To regulate the soil acidity to pH 4,we added FeSO_(4) and allowed the mixture to incubate for 30 days.The results demonstrate that the application of three types of organic fertilizers chicken manure(P1),oil palm empty bunch fertilizer(P2),and vermicompost(P3)positively impacts the growth of three soybean varieties.The findings indicate that the application of P2 organic fertilizer can increase vegetative growth almost 50%in soybeans on acidic soil,including plant height,leaf count,and root length.Meanwhile,applying P3 organic fertilizer can boost reproductive growth responses in soybeans on acidic soil,such as pod number(from around 0-4 unit to 42-51 unit),grain number(from around 0-5 unit to 88-90 unit),and grain weight(from around 0-0.37 g to 12-25 g).Organic fertilizer has the potential to regulate soil pH,promoting higher yields of soybeans under acidic stress.
基金supported by National Science Foundation for Young Scientists of China(Grant 41702143)Major basic science and technology projects of CNPC(2021DJ0206-03)。
文摘The lacustrine organic-rich shale in the Permian Lucaogou(LCG)Formation of the Jimsar Sag,Junggar Basin,is one of the main shale oil plays in China.In this paper,geological and geochemical research techniques were employed to evaluate the geochemical variability of the lacustrine shale and the pro-duction of organic matter and its preservation conditions.The LcG Formation is characterized by its complex mineral compositions and a wide range of organic matter richness and quality.The presence of high proportions ofβ-carotane and C2g steranes,indicates that the organic matter mainly originated from phytoplankton and aquatic algal-bacterial organisms,especially cyanobacteria.This study found that the productivity of the Lower LCG Member(P2li)was highest,and the Middle LCG Member(P_(2)l_(2))was the lowest.During the deposition of the Lower LCG Member,the lake's bottom water was predominantly a reducing environment,and the degradation of organic matter was largely a result of bacterial sulfate reduction.During the deposition of the Middle and Upper LCG members,the lake's bottom water was mainly oxidizing,and the degradation of organic matter was likely to be caused by aerobic processes.Based on a comprehensive analysis of the origin and production of organic matter,as well as its depo-sitional environment and preservation conditions,two organic matter accumulation models were pro-posed to explain the distribution of the organic-rich shale.In model A,the high influx of volcanic ash released nutrients and brought abundant sulfate into the water,the accumulation of organic matter was mainly controlled by the preservation of organic matter,which was mainly controlled by BsR.In the model B,the influx of volcanic ash was small,organic matter was mainly degraded by oxygen and the accumulation of organic matter is mainly determined by the production of organic matter.
基金The National Key Basic Research Special Foundation of China under contract No.2013CB965101the Marine Science and Technology Foundation of the South China Sea Sub-administration,SOA,China under contract No.1624
文摘The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeochemistry of DOP is in its infancy. In the present study, monthly data between 2000 and 2014 were used to analyze the temporal and spatial distributions of DOP in the Mir Bay, the northern South China Sea. The DOP residence time(TDOP) was also investigated using a simple regression analysis in combination with chlorophyll a(Chl a) measurements while excess DOP(ΔDOP), produced by the biogeochemical processes of autotrophic production and heterotrophic removal, was determined using a two-component mixing mass-balance model in combination with salinity measurements. The results showed that the DOP concentration was(0.017±0.010) mg/L higher in the surface-water compared with the bottom-water and higher in the inner Tolo Harbour and waters adjacent to Shatoujiao compared with the main zone of the bay. Although seasonal changes and annual variability in the DOP were small, the surface DOP concentration was higher in the wet season(April–September)than in the dry season(October–March) due to the impacts of seaward discharges and atmospheric deposition into the bay. Measurement and regression results showed that the DOP release rate from phytoplankton production was about 1.83(gP)/(gChl a) and the TDOP was about 7 d, which implied that the DOP cycle in the bay was rapid. The ΔDOP was calculated from the model to be about 0.000 mg/L in the main zone of the bay and about 0.002 mg/L in the inner Tolo Harbour and waters adjacent to Shaotoujiao, suggesting that the autotrophic production of DOP was almost balanced by the heterotrophic removal in the main zone of the bay and dominated in the inner Tolo Harbour and waters adjacent to Shaotoujiao. In conclusion, the Mirs Bay is very productive and fairly heterotrophic.
基金supported by grants from the National Key R&D Program of China(2016YFC0500302)the National Natural Science Foundation of China(U1808201)+1 种基金Strategic Leading Science&Technology Programme,CAS(XDA23070100)the Liaoning Revitalization Talents Program(XLYC1807102).
文摘Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic value,NTFPs have faced the problem of over-exploitation,and the key to solve this problem is to determine the feasible way of sustainable utilization of NTFPs.Harvest intensity is one of the most important and easily controlled utilization factors,which can greatly influence the plant individual survival,growth and reproductive performances,and even the population structure and dynamics.Therefore,we chose two common and important NTFPs species with different marketable parts(i.e.,Acanthopanax senticosus with tender leaves and Aralia elata with tender buds)as our study objects.Aiming to determine the optimum harvest intensity for sustainably utilizing both NTFPs species,five levels of harvest intensity treatments(i.e.,control,light,medium,high and severe)were designed to assess the effects of harvest intensity on their marketable organ yield,plant growth and reproductive performances.Results:The biomass growth rates of marketable organ and plant growth of A.senticosus under light harvest intensity treatment were significantly higher than those under other harvest intensities.The plant height growth and 1000-seed weight of A.elata under severe harvest intensity treatment were significantly lower than those under control treatment.Conclusions:The light harvest intensity with 25% leaf removal and the high harvest intensity with all terminal buds harvested are the optimum harvest intensity to maintain the sustainable utilization of A.senticosus and A.elata,respectively.These findings could provide managers with basic but practical guidance for making decisions about the sustainable harvest management plan for the cultivated NTFPs species,and further provide a theoretical basis for managers to establish the harvest regulations for wild NTFPs species.Consequently,the local residents or communities can improve their income while ensure the sustainable development of wild NTFPs.
文摘Animal production depends on nutrient utilization and if done there is an accelerated momentum towards growth with a low cost to feed ratio Public concern over the consumption of pork with antibiotic residues of the animals fed with antibiotic growth promoters (AGP) has paved the way to use other additives like herbs and their products, probiotics, prebiotics etc. Numerous feed additives are in vogue for achieving this target and one such classical example is the usage of organic acids and their salts. Usage of organic acids was in progress for over four decades. Early weaned piglets are (3-4 weeks age) exposed to stress with a reduced feed intake, little or no weight gain. This post weaning lag period is due to a limited digestive and absorptive capacity due to insufficient production of hydrochloric acid, pancreatic enzymes and sudden changes in feed consistency and intake. Lowering dietary pH by weak organic acids was found to overcome these problems. The main activity of organic acids is associated with a reduction in gastric pH converting the inactive pepsinogen to active pepsin for effective protein hydrolysis. Organic acids are both bacteriostatic and bactericidal. Lactic acid has been reported to reduce gastric pH and delay the multiplication of an enterotoxigenic E. coil These acids are the intermediary products in Kreb's cycle and thus act as an energy source preventing the tissue breakdown resulting from gluconeogenesis and lipolysis. Excretion of supplemental minerals and nitrogen are minimized with organic acids as these form complexes with minerals and aids for their bio-availability. Short chain fatty cids like acetic, propionic and n-butyric acid produced by microbial fermentation of dietary fibre in the large intestines may increase the proliferation of epithelial cells and have stimulatory effects on both endocrine and exocrine pancreatic secretions in pigs. Organic acids also enhances apparent total tract digestibility and improves growth performance. It is concluded that organic acids and their salts increase the protein utilization especially in weaner pigs and improves production indices.
基金supported by the National Natural Science Foundation of China(40471066)the Knowledge Innovation Program of the Chinese Academy of Sciences(KZCX1-SW-01-05).
文摘Paddy field is an important land use in subtropical China. Development of high soil fertility and productivity is the management goal of paddy field, Fertilization and management practices have not only influenced the status of organic matter and nutrients in the soil but also affected the environmental quality. This article investigates the contents of organic carbon and the nutrients, and the change over the last 20 years in highly productive paddy soils and their environmental application. Field soils were sampled and the analytical results were compared with the corresponding values in the Second Soil Survey in Yujiang County of Jiangxi Province, China. The results showed that surface soils at a depth of 0-10 cm in highly productive paddy fields in Yujiang County of Jiangxi Province had contents of organic carbon (20.2 ±3.88) g kg^-1, total nitrogen (2.09±0.55) g kg^-1, and available phosphorus (42.7 ±32.7) mg kg^-1, respectively, which were all at very rich levels. Over the last 20 years, the organic carbon pool of the highly productive paddy soils reached a steady state. Total N and available P significantly increased, whereas available K changed a little. The amount and percentage of P immobilization in the surface soil (0-10 cm) of highly productive paddy fields were (142.7 ~ 41.1) mg kg-~ and (36.2~ 10.4)% of added P, and CEC (7.93 ~ 1.32) cmol kg-~. These two parameters were not higher than the mean values of paddy soils and upland red soils in the areas. Results also showed that fertilizer P in highly productive paddy soils had a high mobility and was prone to move toward a water body, which is the main source of nutrients causing eutrophication. Because of a weak K-fixing capacity, the available K content was not high in highly productive paddy soils. This suggests that attention should be paid to the K balance and the increase of soil K pool.
基金the National Natural Science Foundation of China(No.91958213)the National Program on Global Change and Air-Sea Interaction(No.GASI-GEOGE-02)+2 种基金the International Partnership Program of the Chinese Academy of Sciences(No.133137KYSB20170003)the Special Fund for the Taishan Scholar Program of Shandong Province(No.ts201511061)the National Key Basic Research Program of China(No.2013CB429700)。
文摘Seafloor hydrothermal vent fields(SHVFs) are located in the mid-ocean ridge(MOR),backarc basin(BAB),island arc and hot-spot environments and hosted mainly by ultramafic,mafic,felsic rocks,and sediments.The hydrothermal vent fluids of SHVFs have low oxygen,abnormal pH and temperature,numerous toxic compounds,and inorganic energy sources,such as sulfuric compounds,methane,and hydrogen.The geological,physical,and chemical characteristics of SHVFs provide important clues to understanding the formation and evolution of seafloor hydrothermal systems,leading to the determination of metal sources and the reconstruction of the physicochemical conditions of metallogenesis.Over the past two decades,we studied the geological settings,volcanic rocks,and hydrothermal products of SHVFs and drawn new conclusions in these areas,including:1) the hydrothermal plumes in the Okinawa Trough are affected by the Kuroshio current;2) S and Pb in the hydrothermal sulfides from MOR are mainly derived from their host igneous rocks;3) Re and Os of vent fluids are more likely to be incorporated into Fe-and Fe-Cu sulfide mineral facies,and Os is enriched under low-temperature(<200℃) hydrothermal conditions in global SHVFs;4) compared with low-temperature hydrothermal sulfides,sulfates,and opal minerals,high-temperature hydrothermal sulfides maintain the helium(He) isotopic composition of the primary vent fluid;5) relatively low temperature(<116℃),oxygenated,and acidic environment conditions are favorable for forming a native sulfur chimney,and a "glue pudding" growth model can be used to understand the origin of native sulfur balls in the Kueishantao hydrothermal field;and 6) boron isotope from hydrothermal plumes and fluids can be used to describe their diffusive processes.The monitoring and understanding of the physical structure,chemical composition,geological processes,and diverse organism of subseafloor hydrothermal systems will be a future hot spot and frontier of submarine hydrothermal geology.
文摘Irrigation in lowland rice production systems in Sub-Saharan Africa (SSA) is mainly based on traditional surface irrigation methods with continuous flooding practices. This irrigation method ends up using a lot more water that would have otherwise been used to open more land and be used in other water-requiring sectors. Various studies suggest Alternate Wetting and Drying (AWD) as an alternative practice for water management that reduces water use without significantly affecting yield. However, this practice has not been well adopted by the farmers despite its significant benefits of reduced total water use. Improving the adoption of AWD using irrigation Decision Support Systems (DSSs) helps the farmer on two fronts;to know “how much water to apply” and “when to irrigate”, which is very critical in maximizing productivity. This paper reviews the applicability of DSSs using AWD in lowland rice production systems in Sub-Saharan Africa.
基金Supported by Bidding Project for Social Science Foundation of Hebei Agricultural University in 2017(ZB201702)Key Project of Humanities and Social Science Foundation of Hebei Provincial Department of Education(ZD201713)Social Science Foundation Project of Hebei Agricultural University(SK201604)
文摘With the objective of building a well-off society in an all-round way reaching the decisive stage,poverty alleviation enters the final stage,and rural financial poverty alleviation is increasingly becoming a hot topic of various circles of society. In order to accelerate the poverty alleviation and provide references and recommendations for further development of theory and practice of financial poverty alleviation,this paper made an overview of the organization system,operation mechanism and service products of rural financial poverty alleviation,elaborated the development path of financial poverty alleviation,and came up with recommendations for financial poverty alleviation.