基于Nerlove模型的玉米供给反应研究——以吉林省为例

STUDY ON MAIZE SUPPLY RESPONSE BASED ON NERLOVE MODEL——TAKING JILIN PROVINCE AS AN EXAMPLE

[目的]吉林省是以玉米为主要粮食作物的产量大省,吉林省玉米生产在保障国家粮食安全方面发挥着重要的作用。2016年国家取消玉米临时收储政策,实行"价补分离"政策(既市场化收购+补贴)。在玉米价格逐步市场化的形势下,为探究吉林省玉米种植面积对价格变动的反应程度,[方法]文章利用1985—2015年吉林省玉米种植面积、玉米平均出售价格、玉米的物质成本投入、玉米与大豆的每667m^2收益比值、玉米与水稻的每667m^2收益比值的时间序列数据,通过运用Nerlove模型,测算吉林省玉米播种面积对价格、物质成本、与大豆和水稻的每667m^2收益比值的供给反应。[结果]吉林省玉米的短期供给弹性为0. 49,长期供给弹性为0. 63,短期供给弹性和长期供给弹性均小于1,缺乏弹性,吉林省玉米种植面积对价格变动的反应较为迟钝。[结论]提出完善农业耕作制度,推进玉米目标价格制度改革,优化玉米收购市场结构政策建议。

Jilin province is a province with a large yield of corn as its main food crop. Maize production in Jilin province plays an important role in guaranteeing national food security. In 2016,the government abolished the temporary maize storage policy and implemented the policy of "separation of price and subsidy"(market-oriented purchase and subsidy). This study explored the response degree of maize planting area to price changes in Jilin province under the situation of gradual marketization of corn price. Based on the time series data of maize planting area,maize average selling price,material cost input of maize,the ratio of maize to soybean per mu and the ratio of maize to rice per mu in Jilin province from 1985 to 2015,it calculated the supply response of maize planting area to price,material cost and the ratio of per mu income to soybean and rice by using Nerlove model. The results showed that the short-term supply elasticity of corn in Jilin province was 0. 49,and the long-term supply elasticity was 0.63. Both the short-term supply elasticity and the long-term supply elasticity were less than 1,and the elasticity was lacking,which meant that the planting area of corn in Jilin province was relatively insensitive to price changes.Therefore,some policy suggestions are put forward to improve the agricultural farming system,to promote the reform of maize target price system and to optimize the market structure of maize purchasing.