Study On The Dual Margin Of China’s Agricultural Export Growth From The Perspective Of Duration

Although China’s agricultural exports have achieved significant scale expansion after China’s accession to the WTO,export growth has shown a downward trend,particularly affected by the economic crisis in 2008,negative growth of-7%occurred in 2015.Many scholars believe that a high degree of export concentration may be the main reason for causing exports to be blocked.Therefore,we believe that increasing the degree of diversification of exports in order to suppress fluctuations in export growth and enhance the ability to resist external risks.In fact,China has adopted a diversification strategy for exports since its entry into the WTO.By 2015,China has exported nearly 800 agricultural products to 215 countries and regions around the world.However,the trade share of more than 700 of these products is less than 25%,and there is still a general entry and exit of these products.In other words,the long-term implementation of the diversification strategy does not fully play its due role.According to the latest development of the New-new trade theory,The role of diversification which emphasize the extensive margin is based on the assumption of stable trade.that is,assuming that export products will continue for a long time once they choose to enter the market.So diversified product exports provide the short-term drivers for export growth on the one hand,and the newly-added products will be transformed into products that are continuously exported,which in turn will provide long-term growth drivers for intensive export growth on the other hand.However,this assumption is not established in the trade practice,zero trade flow is universal,which means that diversified exports often cannot produce long-term contribution to export growth.In other words,the duration plays a very important role in safeguarding the above-mentioned conversion mechanism.this effect may be more important for agricultural products,because the adjustment period of agricultural products is longer,and if the duration of agricultural products is short,The long-term stability of agricultural product export growth is even more unfavorable.Therefore,paying full attention to the role of duration in export growth has important policy values and practical significance.However,from the existing literature,the research on the dual margin of export growth focuses on the discussion of the dual marginal structure and influencing factors,and rarely relates to the product sustainability characteristics of export growth;the literature on the duration of exports does not break through the analysis framework for the description of the duration characteristics and the influencing factors.There is little discussion about the effect mechanism of the duration on the export growth,and how the performance of export growth will change after considering the duration factor.Therefore,the purpose of this paper is to explore the potential for the future development of China’s agricultural export growth by clarifying the theoretical mechanism which duration affects the marginal export growth.This article believes that an increase in the duration of exports is conducive to the mutual promotion of the dual margins,so that new products can be more integrated into the intensive marginal product sets,and expand the "thickness" of the intensive margins of export growth,and promot the long term contributin of new products to export growth.in particular:First of all,this article describes and analyzes the diversified characteristics of China’s agricultural exports.The results show that:①Over 50%of China’s product categories are unsuccessful export competition models(non-quality competition and non-price competition),and the international competitiveness level measured by RCA index is generally lower than 0.5,exports are still concentrated on a few agricultural products.Further investigation of the duration characteristics shows that the export of a large number of weakly competitive agricultural products makes the corresponding duration generally less than 5 years,this causes the product to enter and exit the market more frequently.In turn,it suppresses the positive contribution of intensive margins to the growth of exports and affects the long-term stability of export growth.Secondly,using the survival analysis method to analyze the export duration of Chinese agricultural products,The results show that:①There are strong multi-segment trade phenomena in China’s agricultural exports,resulting in average and median duration of China’s agricultural exports being only 5.49 years and 2 years respectively.②There is a divergence phenomenon in the long-term export duration,which indicates that there is still a strong exit risk when the product enters the international market for a long time(around 9 years),the main source of low sustainability is the pull-down effect of bulk agricultural products and intermediate processed agricultural products.③At the same time,these shorter duration products are more exported to countries in less developed regions.④As a result,the duration of the overall export was lower than that of developed countries such as France,Netherlands and United States.Third,this paper embeds the duration into the dual marginal decomposition model of export growth,and analyzes the dual margin issue of export growth after considering the export duration factor.The results show that:①Without considering the duration factor,98%of China’s export growth depends on intensive margins,and the contribution of expanding margins is very limited.The phenomenon of frequent entry and exit of products makes export growth more dependent on the contribution of intensive margins,and the average contribution of intensive marginal to export growth has reached 98%.②At the same time,the shorter duration severely inhibited the contribution of new products or extensive margin to export growth;the average contribution of new products to export growth was about 22%,but was affected by the 20%product exit risk rate,The contribution to the extensive margin has less than 5%.③Further,after considering the duration of exports,China’s agricultural exports depend heavily on the export depth;this leads to more volatile characteristics of export growth,which will affect the long-term sustainable development of export growth.Based on this,we further analyzes the potential contribution of duration to the export growth.The results show that:① Compared with the export depth or the expansion of the export scale,the increase of export duration is more conducive to the long-term stable development of export growth.② The potential contribution of the increase in duration to the overall export growth of China’s agricultural products was 3.93%;The rate in intermediate agricultural products,final consumption agricultural products,and agricultural related products are 0.52%,2.57,and 0.75%respectively.At the same time,there are potential growth in the "export deepening" of agricultural related products.The average"potential growth contribution rate" is 0.70%,making the comprehensive potential contribution rate of agricultural related products at 1.65%.③The export growth potential of the product through the different dimensions of export competition model also leads to the conclusion that,no matter the product growth of successful export competition model(quality competition and price competition)or product growth of the unsuccessful export competition model with huge trade deficit(Non-quality competition and non-price competition),the contribution of sustained trade to growth potential is enormous,the"potential growth contribution rate" of "export deepening" is 0.94%and 0.72%.equivalent to about three times their respective actual growth contribution rate.Compared with previous studies,the innovation of this paper is reflected in the following aspects:First,combining the two important empirical research based on the theory of heterogeneity,through the establishment of a mechanism of export duration and the dual margin of export growth,we system analyzes how the duration of exports ultimately influences export growth through the dual margin.Secondly,the "counter-factual test" method was introduced to explore the potential growth of China’s agricultural exports.Differentiating from the previous indirect measurement of export growth potential,The"counterfactual" approach can directly affect the decomposition of export growth in the marginal path,and effective identify the influence of export depth and duration on export growth;This will help the system and accurately grasp the potential growth of China’s future agricultural export.