Can whole steps of grain production be outsourced? Empirical analysis based on the three provinces of Jiangsu,Jilin,and Sichuan in China

Jiacheng Liu ,Shengzhi Mao ,Qiufen Zheng ,Zhigang Xu#

1 School of Finance and Taxation,Nanjing University of Finance and Economics,Jiangsu 210023,China

2 School of Economics,Southwestern University of Finance and Economics,Sichuan 611130,China

3 School of Economics and Management,Nanjing Agricultural University,Jiangsu 210095,China

Abstract Certain outsourcing services for agricultural management in China,such as pest control in grain production,have experienced prolonged sluggishness,contrasting with the relatively high level of outsourcing services observed in harvesting,land preparation,and sowing.This study examines the feasibility of implementing whole-step outsourcing in grain production by conducting a case study of rice and maize production in Jiangsu,Jilin,and Sichuan provinces in China.The provision of outsourcing services hinges on two essential conditions: technological advancements fostering specialized production and economies of scale,coupled with a market size sufficient to realize the aforementioned potential economies of scale.The results showed that outsourcing pest control or harvesting services had varying economies of scale.The outsourcing services in pest control were less common than in harvesting services,and their marginal growth space of the economies of scale with technological change was also smaller.Determined by the operational characteristics of pest control itself,the market scale of its professional services is small.Therefore,achieving the whole-step outsourcing of grain production necessitates not only technological innovation but also effective policy interventions to overcome the constraints of market scale.Such interventions include (1) optimizing crop layouts between planning regions and reducing land fragmentation and (2) supplying timely and effective inter-regional agricultural information for service providers aided by information technology.

Keywords: outsourcing services,economy of scale,technical conditions,market scale

1.Introduction

Agricultural production outsourcing services play important roles in upgrading the mode and realizing the scale and mechanization of agricultural production.During the past 30 years,urbanization and industrialization in China have led to shortages in the agricultural labor force and rising labor costs (Dongetal.2018;Liuetal.2019a;Maetal.2019).There is widespread societal concern regarding who will be farming and how they will be farming,as a significant number of farmers have been handing cultivated land,sowing,harvesting,and even plant protection over to professional service organizations (Wangetal.2011;Cai and Cai 2014).This kind of professional service can realize the large-scale and mechanization of decentralized farm production and management to a large extent without changing land contracts or management rights,thereby not only conforming to China’s national conditions but also solving the problem of labor force shortage (Ji Cetal.2017;Liuetal.2019b;Dengetal.2020;Quetal.2021).

After years of practice,the outsourcing services of some grain production steps have reached high levels.However,the pest control,an important part of grain production,has had a low level of outsourcing service for a long time1According to a special survey on agricultural productive service organizations organized by the School of Economics and Management of Nanjing Agricultural University in 2018 in Jiangsu,Sichuan and Jilin provinces,China,the proportions of cultivated land area operated by outsourcing in tillage and land preparation were 61.1,15.2,and 40.1%,respectively,the proportions of cultivated land area operated by outsourcing in harvesting were 72.6,32.1,and 38.3%,respectively,and the corresponding proportions of disease and pest control were much lower at only 13.8,3.8,and 6.0%,respectively..In addition to improving production efficiency(Picazo-Tadeo and Reig-Martínez 2006;Igataetal.2008;Beltonetal.2018),contributing to farm income (Machilaetal.2015;Baiyegunhietal.2019),and alleviating shortages in agricultural labor and funds (Zhao 2014),outsourcing services have also improved the welfare of agricultural workers and have reduced workloads as the aging and feminization of the agricultural labor force continue2Although pest control does not require heavy manual labor,each crop needs to be sprinkled many times,while there are high requirements for application times,pesticide ratios,and spraying uniformity.If such operations could be outsourced to professional service organizations at lower costs,then the welfare of female and elderly workers would undoubtedly be improved.(Liuetal.2019a;Xuetal.2022).However,the development of outsourcing services in the prevention and control of diseases and pests in grain production in China has been sluggish for a long time.Sunetal.(2016 and 2017) believed that the supervision of outsourcing has been difficult and has significantly inhibited the outsourcing demands of farmers.After testing farmers’outsourcing behaviors from the perspective of their psychological cognition and willingness to outsource,Duanetal.(2017) believed that their cognition of outsourcing behaviors in terms of the ease of use and effectiveness of the outsourcing services had played significant roles.Zhang and Luo (2018),as well as Yangetal.(2019),believed that economies of scale were the premise for outsourcing service supply.Applying the theory of the division of labor,Liu and Xu (2021)empirically tested the constraints of market scales on the level of the development of outsourcing services along the spatial and temporal dimensions of market scales.

Most scholars have analyzed the reasons from the perspective of service demand.Although some scholars have also discussed the conditions for the occurrence and development of outsourcing services from the perspective of service supply (Yangetal.2013;Luo 2017;Zhangetal.2017),the following two points still need further study.

First,although economies of scale are the prerequisite for developing outsourcing services,the economies of scale of outsourcing services in different steps may vary and exhibit dynamic disparities due to technological changes.There is still a lack of in-depth research on this topic.Professional outsourcing services inevitably require large-scale operations,which inevitably require technical follow-up.It is necessary to deeply investigate the relationship between the economies of scale of outsourcing services and technological changes.For example,compared with the outsourcing services in the harvest with harvesters (even low-horsepower harvesters),the initial investment of outsourcing services in the plant protection process with low-level technologies(such as backpack medicine buckets) is much lower.The lower service areas are required to share fixed investments;therefore,the level of economies of scale of outsourcing services may be lower.Then,with advanced technologies such as plant protection by unmanned aerial vehicles (UAVs),would economies of scale be prominent?What are the constraints if economies of scale undergo only slight changes? Grain production consists of multiple steps,each with different technical conditions and change characteristics.When outsourcing services with common characteristics are applied to various steps of differentiated grain production,we need to be careful.

Second,although a few scholars have emphasized the key role of the expansion of market scale in the development of outsourcing services and empirically tested the restriction mechanism of agricultural season constraints in the supply of outsourcing services,there has been a lack of in-depth analyses of the factors that further restrict the spatio-temporal expansion of the market scales of outsourcing services.The scale of grain production is subject to not only the immobility of land factors but also the timeliness of natural factor inputs.To fully expand the market scale of outsourcing services,on the one hand,it is required to provide services within the region as much as possible;on the other hand,it is required to provide inter-regional outsourcing services as much as possible while making full use of the interregional agricultural season difference.However,the factors restricting the market expansion of outsourcing services for grain production still need further study.As agricultural production is subject to the dual constraints of the agricultural season and land,the expansion of market scale may depend not only on the commonly recognized technical level,the degree of land fragmentation,and the degree of the standardization of operations on contiguous plots but may also depend on the length of the agricultural season in a particular region and the degree of interregional overlap of agricultural seasons.

The marginal contributions of this study are as follows.First,this study has relied on the advantages of data to compensate for the deficiency in quantitative analyses about the economies of scale of outsourcing services in grain production.For a long time,most of the literature has focused on service demand but has ignored service supply and the collection of input-output information of outsourcing service in all steps.Second,from the perspective of technical constraints and market expansion constraints on the realization of scale economy,this study explored the reasons for the slow development of outsourcing services in the process of disease and pest control and provided a new understanding of how to realize the whole steps outsourcing of China’s grain production.

2.Theoretical hypotheses

Suppose that the final price of outsourcing service supply isPs,the average activity cost isCs,and the lowest activity cost for ordinary farmers isPd;the conditions for outsourcing service supply are:

a)Ps≤Pd;otherwise,there is no demand for outsourcing services.

b) (Ps-Cs)·Q≥Ya,whereQrefers to the total service area,andYarefers to the maximum annual income obtained by the service provider if it engages in nonoutsourcing services.

Assuming thatPdandYaare fixed,asCsdecreases whileQincreases,the probability of the service supply increases.

In Fig.1,the horizontal axis represents the operational scale,the vertical axis represents the cost or service price,and the curve represents the average cost function of outsourcing services.The costCsis determined by the form of the production function and market scale.The cost function may take different forms,as shown in Fig.1-A and B.The total market scaleQdepends not only on the inflection pointQ＊ (where the average costCsis also the lowest),which designates the optimal economy of scale,but also on the actual market scale constraints.Q1andQ2represent two different types of actual market scale constraints.

Fig.1 Schematic diagram of net income of outsourcing services under different average cost curves.

According to Fig.1-A,if the economy of scale at point(Q＊,Cs) is greater than the total scale under market constraints (i.e.,the market scale that achieves the lowest cost advantage is constrained by the actual scale),then the total income is (Ps-C(Q1))Q1;otherwise,it is (Ps-C(Q＊))Q＊.

According to Fig.1-B,if the economy of scale at point(Q＊,Cs) is greater than the total scale under market constraints,then the total income is (Ps-C(Q1))Q1;otherwise,it is (Ps-C(Q＊))Q2.

The lowest costCsand its corresponding market scaleQ＊ are related to the technical characteristics,whereas the actual market scales (Q1andQ2) are related to the labor productivity per unit time (i.e.,the technical level)and the effective operational hours under the constraints of the agricultural season.

The technologies of different steps in grain production would be different,so the corresponding economies of scale of outsourcing services would also be different.Then it is assumed that the production cost function of an outsourcing service is:

whererfKfis the fixed cost,rfis the annual interest rate,Kfis capital investment,wv·Nvis a variable cost,wvis the wage rate,andNvis the number of workers.

The corresponding output (service area) function is:

whereαis the proportion of labor in the production function,andAfrepresents total factor productivity.

Nv=which is then substituted into eq.(1)to obtain:

The first derivative of the average cost curvefromQis used to solve for the point at the lowest average cost.The slope of the average cost curve is:

where 0＜α＜1.Then＞0 when the slope is 0,i.e.,the lowest point on the average cost curve.Therefore,the following formula can be obtained:

Assuming that the wage rate and annual interest rate remain unchanged,eq.(5) implies thatQ＊is directly proportional toKfandAf.

When the initial input cost andQ＊are determined,the level of the lowest costC(Q＊) depends on the rate of the decline in the slope of the average cost curve.As shown in Fig.2,a higher rate of decline to the left of (Q＊,Cs)implies a lower final average cost.Therefore,the second derivative of the average cost curvetoQshows that the rate of decline in the slope of the average cost curve is:

Fig.2 Schematic diagram of minimum costs under different rates of change in slope of average cost curve.

which can be simplified to:

Assuming that other conditions remain unchanged andKfis fixed,the rate of the change in the slope of the average cost curve depends on the sign ofand the size ofAf.If＞0,i.e.,then greaterAfimplies a lower decline in the slope to the left of the inflection pointQ＊.Whenthen greaterAfimplies a greater decline.Therefore,whether technological progress could eventually lead to a decline in production costs depends on the proportion of the contribution rate of labor factors to the production function.

In reality,the operational difficulty of the step itself determines the costs of technical improvements in different steps.Spraying pesticides requires less physical labor but more labor productivity than harvesting.The marginal change in labor productivity in aerial operations is much greater than that in ground operations.For this reason,we can observe phenomena such as shifts fromtraditional manual spraying to mechanical arm spread spraying,a wider range of marginal changes in labor productivity for aerial crop dusting,and a shift from using harvesting machinery with smaller horsepower to higher horsepower.Traditional,small-scale farmers generally use backpack pesticide buckets for manual spraying,which has a low level of labor productivity at about 1 mu h-1(1 mu is about 0.067 ha).Modern technologies include the self-propelled disperser and plant protection UAV.The working area per unit hour can reach 30-40 mu,large machinery can even reach 60-70 mu,and aircraft plant protection can even exceed 100 mu.The marginal cost of improvements in labor productivity is low,so the fixed input in the early stage is relatively low compared with the harvesting and may lead to a lower point for the economy of scale at the lowest cost.

The above technical characteristics of pest control may result in a lower labor-capital ratio of pest control for the same unit area of operation (pest control is technologyintensive,and harvesting is labor-intensive),so the share of labor in the production function is lower.Ifαis lower than 1/2,the rate of the change in the slope of the average cost curve may be lower with the increase of total factor productivity in technological change,indicating that the range of the change in the economies of scale of specialized operations in this step would be smaller with technological change.Of course,this conclusion remains to be further tested by the data.

According to the above theory,the decision to outsource service supply depends not only on the lowest average cost determined by the technical characteristics and the maximum operational scale at the lowest cost but also on whether the expansion of the market scale is limited in reality.Even if changes in the technical conditions make it possible for the average cost to decline significantly,restrictions due to the actual market scale could make the potential minimum cost difficult to achieve.Moreover,the annual net income is insufficient and would inhibit the development of outsourcing service supply.The market scale determined by service hours and labor productivity has become another important factor in the decisions to outsource service supply.Specifically,the total market scale depends on the operational area per hour and the total service hours.

From the perspective of working scale per hour,it is not only related to the new technology used but also related to the applied conditions of the new technology.Compared with animal power and even manpower,the efficiency of mechanical operations,especially largescale mechanical operations,has been greatly improved.The more contiguous a plot,the larger a contiguous area,and the more standard an operation process on the contiguous plot,the greater the potential to maximize the mechanical operations.From the perspective of the total service hours of grain production,the total service hours are related to both the service hours in a region and the service hours between regions.Agricultural production is seasonal.If the agricultural season is delayed,then the operations will be invalid.Therefore,the service hour in an area depends on the agricultural season elasticity of a link operation (i.e.,time quantum between the earliest and latest points of the operational seasons that does not affect the normal growth of crops).The greater the agricultural season elasticity in an area,the more conducive the season is to prolonging the service hours in that area.On the contrary,the more urgent an agricultural season,the less conducive to prolonging the service hours in that area.From the perspective of inter-regional service hours,the more the operational season for inter-regional grain production can be just in succession,the more conducive to making full use of the advantage of latitude span to prolong the total number of operational hours.This is hereafter referred to as the inter-regional agricultural season coincidence degree.The higher the coincidence degree,the less conducive to prolonging the service hours.Therefore,the increase in the total operational hours of grain production outsourcing services depends on the elasticity of the agricultural season in a region and the coincidence degree of the agricultural seasons in various regions.As shown in Fig.3,the horizontal axis represents the length of the farming season,and the vertical axis represents the latitude.The rectanglesaandbrepresent two regions,respectively.The length of the two rectangles represents the effective agricultural period of agricultural production in the two regions.Limited to the production capacity of the outsourcing service,the service supplier cannot complete the agricultural production of regionaand regionbat the same time if the effective agricultural period in regionbcoincides with that in regiona.On the contrary,if the agricultural seasons of regionaand regionbare successive,the service supplier can continue to provide services for regionbafter completing the production operation in regiona.In this way,the total effective production time for service providers will be extended.

Fig.3 Schematic diagram of market scale of grain production outsourcing services.Operational efficiency depends on technological progress,land endowment,degree of agricultural land contiguity,degree of unity of crop layout,and cultivation technology.Operational hours depend on the elasticity of agricultural season in an area and the overlap of agricultural seasons between areas.Left: only spatial dimension of economy of scale;Right: both spatial and temporal dimensions of economy of scale.

In reality,the spatio-temporal dimensions of the market scales of pest control are significantly different from those of tillage,planting,and harvesting.Pest control is explosive and sudden,with urgent operational seasons and short windows for effective operations,i.e.,the elasticity of the agricultural season in the relevant region is low,and the coincidence degree of the agricultural seasons between regions is high.In contrast,the operational seasons of harvesting are relatively predictable,the effective operational windows are long,and the operational seasons in different latitudes are sequentially distributed.The wide latitude span between Northern and Southern China has the advantage of cross-regional services that could be provided to significantly extend the total effective operational hours of harvesting outsourcing services.Therefore,the effective operation hoursTsof harvesting can be expressed asTld,wherejstands for latitude.Its time advantage is much higher than the effective operational hours of specialized operations in pest control:wherenstands for total latitude,andn≥j.In addition,under China’s household contract responsibility system,plots are fragmented,and farmers make decentralized decisions,which makes it difficult to integrate plots,while the low degree of standardization of operations on contiguous plots leads to small spatial scales.

In sum,the increase in the economies of scale brought about by technological progress and the small market scale constraints are the necessary conditions for the supply of outsourcing services.However,the natures of the economies of scale of different steps are different because of technical characteristics.The spatio-temporal market scale constraints on different steps are also different,which may be the core reason for the different development levels of outsourcing services in all steps of grain production.

Accordingly,we proposed the following two hypotheses to be tested.

Hypothesis 1: For pest control,the economy of scale and its increase due to technological change are smaller than for harvesting.

Hypothesis 2: The greater the elasticity of the agricultural season in a region and the lower the degree of inter-regional agricultural season overlap,the higher the probability of outsourcing service supply.

3.Data and methods

3.1.Data

The analysis of this study is based on the first-hand survey data organized by the author’s research team.The interviews involved topics such as regional planting structure,purchase of production outsourcing services,mechanical and manual inputs of outsourcing service supply,and personal and family characteristics.Multistage random sampling method is adopted for data collection,and the specific sampling rules are as follows.(1) Provincial sample: Jilin,Jiangsu,and Sichuan are selected as sample provinces by taking into account economic development,grain production,and regional distribution.Jilin is located in the northeast plain,with good agricultural resources and the main grain production area in China;Jiangsu is located in the plain of the middle and lower reaches of the Yangtze River,the economically developed southeast coastal area of China,and also an important agricultural production area of China;Sichuan is the representative of the region between the southwest basin and the mountainous region,with a shortage of arable land resources and a large number of labor exports.(2) County sample:In each sample province,based on the per capita net income of farmers,3 sample counties are selected by stratified sampling method.(3) Township sample: In each of the 9 sample counties,2 towns were selected by stratified sampling method based on the per capita net income of farmers.(4) Village sample: 6 villages were selected from each sample township by pure random sampling method.(5) Service organization sample:According to the principle of stratified random sampling,28 organizations were selected from 6 villages,and 504 organizations were investigated from 18 towns and townships.The invalid samples were removed,and the samples of 497 service organizations were finally used in this paper.The acquisition of this part of the data made possible quantitative analysis of the economies of scale for specialized services.

3.2.Empirical framework

Measurements of economies of scale of outsourcing servicesWhether there are economies of scale in outsourcing services is determined by whether the average costs of service activities decrease significantly with an expansion of the operational scale.Using the input-output data of outsourcing services provided by service organizations and referring to the production cost model of Xuetal.(2011) to investigate the relationship between land operational scale and production cost,the following econometric model was formulated:

whereACijrefers to the costs per unit area of services andareaijis the total service area provided by service organizationion stepj,Xrepresents other control variables,which include the level of technology,the age of the service provider,level of education,social capital,and non-agricultural work experience,andμijis the random disturbance term.The OLS estimation method was used to estimateα0,β1,β2,andγ.Table 1 shows the descriptive statistical results of the main variables.

Effects of the spatio-temporal dimensions of market scale on outsourcing service supplyTo investigate the factors restricting the spatio-temporal expansion of the market scale of grain production outsourcing services and their effects on outsourcing services.The econometric model is as follows:

whereOSijindicates whether organizationiprovides outsourcing services on stepj.

The agricultural season elasticityTeijis measured by the time quantum between the earliest and latest time points in the operational season.The agricultural season elasticity is different for different steps and different latitudes.With rice production as an example,the average agricultural season elasticity of harvesting is about 7 days,whereas pest control requires 2-3 days.In different latitudes of north and south,the accumulated temperatures and amount of daylight are different.The most flexible agricultural season in the same step could differ by 10-15 days.

Fiijrefers to the inter-regional coincidence degree of agricultural seasons.With service providers assumed to be moving continuously from low latitudes to high latitudes,the coincidence degree would eventually be reflected in the annual accumulated effective operational hours.The higher the coincidence degree,the fewer the total effective operational hours,andviceversa.Based on the research of Liuetal.(2022),we constructed an index of days per labor worked at providing outsourcing services in a year,reflecting the inter-regional time scale.

Land fragmentationFrijis expressed by the contiguous operational area in the total service operational area,such as the proportion of 30 mu contiguous land area in the total service area.For example,the total area that the service provider may work in the whole year is 100 mu,which is distributed on 4 plots of a,b,c,and d.The plot area of a,b,c,and d is 10,50,20 and 20 mu,respectively.Therefore,the proportion of plots with an area of 30 mu or more in the total service area is 50%.The basis for the division standard of 30 mu is mainly from the practical cognition of outsourcing service providers in the field survey.When asked,“How much do you think the size of the plot can make your production efficiency the highest under the current technology level?” 65.8% of the service providers thought that “about 30 mu of plot should meet the needs of the current technology”.

Xrepresents the other control variables,which include the economic development at the village level,topographic conditions,and the type of machinery used for service supply.μijis the random disturbance term.Table 2 shows the descriptive statistical results of the key explanatory variables in eq.(9).

4.Results and discussion

4.1.Analysis of economies of scale for outsourcing services with different technical characteristics

To simulate and calculate the economies of scale of outsourcing services,we used the sample data of current outsourcing services to estimate the average cost curves.To further investigate the changing characteristics of the economies of scale with technological changes,the samples were divided into two categories: ordinary technology and advanced technology.Then,the average cost curves of service supply were estimated.The estimation results are shown in Tables 3 and 4.

With crop and regional differences being controlled,both the outsourcing services of pest control and harvesting have economies of scale,but the degrees ofthe economies of scale are different.As shown in Fig.4,the scope of the economies of scale of outsourcing services for pest control is smaller than those for harvesting.It is easier to enter a stage of dis-economies of scale from the stage of economies of scale.

Table 1 Descriptive statistical results of main variables

Fig.4 Simulation curves of average costs of outsourcing service supplies in pest control and harvesting.ypest and yharv represent the optimal service scale with the lowest cost for pest control and harvesting,respectively.

We divided the technical levels into two groups of samples,low-tech and high-tech,according to the mean value of the technical level,the maximum value of the technical level distribution,or the 60 and 70% quantiles.Then,we estimated the original model to investigate changes in the optimal points of the economies of scale under different technical conditions.Limited to the spatial dimension,Table 4 reports the estimation results with the maximum value of the technical level distribution as the boundary point.As shown in Fig.5,under high-tech and low-tech conditions,the optimal economies of scale for the specialized operations in pest control change slightly from 1,645 to 2,075 mu,the range of the optimal economies of scale increases by 26%,and the production cost at the optimal scale has no significant change.The economies of scale in the harvesting process show highcost advantages with the change in technology as the range of the economies of scale increases from 2,108 to 3,160 mu,which is an increase of 52%,and the average cost at the optimal scale decreases from 27.72 to 7.47 CNY mu-1.

Fig.5 Simulation curves of average costs of outsourcing service supply in each step under different technical levels.pestLT and harvLT represent the optimal service scale with the lowest cost for pest control and harvesting at low technological levels,respectively;pestHT and harvHT represent the optimal service scale with the lowest cost for pest control and harvesting at high technological levels,respectively.

4.2.Analysis of spatio-temporal dimensions of market scale constraints on outsourcing services

This study used the Logit model3The assignment rules for the variable “whether to provide outsourcing services” are as follows: As long as the area of outsourcing services (i.e.,excluding the self-service area) is greater than 0,the Y value is uniformly combined as 1,regardless of the specific service area.to test the effects of the spatio-temporal dimensions of the market scales on outsourcing service supply.The intra-regional elasticity and inter-regional overlap of the agricultural seasons were entered into the model to test the effects of the temporal dimension.The degree of land contiguity was used to test the effects of the spatial dimension.To test the robustness of the estimation results and facilitate comparison,the OLS estimation results are also reported in Table 5.

The model results show that both dimensions significantly affect decisions regarding outsourcing service supply.The lower the degree of land fragmentation,the greater the elasticity of the agricultural season in the region,or the lower the inter-regional overlap of the agricultural seasons,the greater the probability of outsourcing service supply.On the one hand,the empirical results further validate Stigler’s conclusionthat “market size” is an important prerequisite for labor division (Stigler 1951),and on the other hand,it expands the understanding of the connotation of “market size”in the field of agricultural production.Based on the theoretical analysis of this study,with the constraints of the agricultural season,the more fully utilized the agricultural season is,and the better the land conditions for outsourcing service,the larger the market size that can be obtained.

Table 3 Estimation results of econometric model

From the estimation results of the other control variables,the affect direction of each variable is consistent with expectations and existing research conclusions.The larger the household operating area or,the stronger the social capital,the more likely it is to provide outsourcing services.First,the larger the scale of the household operating area,the lower the transactioncost of self-purchasing agricultural machinery compared to purchasing outsourced services.At the same time,due to the indivisibility of agricultural machinery,farmers who purchase agricultural machinery need to reduce average costs by providing additional outsourcing services to other farmers (Ji Y Qetal.2017).Therefore,the larger the household operating area,the more likely it is to provide outsourcing services.Second,from the perspective of social capital,outsourcing service supply requires not only high capital investment for purchasing agricultural machinery but also stable social relationships to obtain sufficient service area.People with stronger social capital often have comparative advantages in capital investment and information acquisition.Such as,Shen (2022) also found that the larger the scale of land management,the more likely the farmers are to provide outsourcing services,and the supplier of outsourcing services is higher than ordinary farmers in human capital.Zhengetal.(2022)and Xuetal.(2023) also found that more and more farmers choose to provide outsourcing services while operating on a large scale of land.On the one hand,they can obtain the market scale to ensure the machine operation capability,and on the other hand,they can obtain a stable income by providing outsourcing services.Zhengetal(2022) also believe that social capital plays an important role in transaction activities such as agricultural land transfer and outsourcing service supply.

Table 4 Technical estimation results of link operations

5.Conclusion and recommendation

This study analyzes the occurrence mechanism of outsourcing services from the perspective of service suppliers.The findings suggest that the cost advantages of specialized operations,in contrast to the operations of ordinary farmers,and the small restrictions of real market scale are the requirements for outsourcing servicesupply.Empirical analysis from Jiangsu,Jilin,and Sichuan provinces in China shows that the economies of scale of outsourcing services in pest control are insufficient because of their technical characteristics and agricultural season constraints.Therefore,the lack of outsourcing services for pest control is due to natural obstacles.

Table 5 Estimation results of econometric model

With the gradual aging and feminization of China’s agricultural labor force and the concurrent employment opportunities,the demand for outsourcing services in agricultural production has gradually increased.Ensuring the supply of corresponding outsourcing services is a practical problem requiring more in-depth research.Although the outsourcing services of farming,planting,and harvesting have developed rapidly and greatly improved agricultural production efficiency,the low level of outsourcing of pest control has not been conducive for a long time to completely easing the constraints of the agricultural labor force and improving production efficiency.Therefore,to give full play to the positive roles of outsourcing services,it is essential to pay more attention to the significance of weak steps in developing outsourcing services.Feasible and effective measures to overcome the constraints of market scale include expanding the scale of land plots,managing land plots in a contiguous manner,as well as timely releasing and integrating agricultural season information using information technology.In addition,given the lack of profits in the supply of specialized services due to the agronomic and seasonal constraints of the pest control itself,appropriate government subsidies can be used to reduce the opportunity cost of the supply of specialized services in this step or improve the rural labor market,as far as possible to ensure employment opportunities in nonbusy farming seasons,which will also help further promote the outsourcing service development of the whole steps of grain production.

Acknowledgements

This study is supported by the National Natural Science Foundation of China (72103088) and the National Social Science Fund of China (20&ZD094 and 21&ZD101).

Declaration of competing interest

The authors declare that they have no conflict of interest.