不同市场结构组合下稀土最优开采路径研究

The optimal extraction paths under different rare-earth market structure combinations

本文从价格视角将我国稀土市场结构的变化历程划分为不同阶段,分别从理论和现实视角上探讨了在国际、国内都是完全竞争市场,国际市场垄断、国内市场完全竞争,国际市场完全竞争、国内市场垄断,国际、国内都是垄断市场条件下稀土最优开采路径及最优耗竭时间,并通过设定参数判断其相对大小关系。发现在一定的假设条件下,开采前期当国内和国际市场都是完全竞争时,稀土最优开采量是最大的;当国内和国际市场都是垄断时,稀土最优开采量是最小的;其他两种市场情况下稀土最优开采量居于中间,当国际市场是稀土的主要消费地时,国际竞争-国内垄断市场情况下稀土最优开采量大于国际垄断-国内竞争市场情况下稀土最优开采量,反之,国际垄断-国内竞争市场情况下稀土最优开采量大于国际竞争-国内垄断市场情况下稀土最优开采量。

China is both the largest supplier and consumer of rare-earth in international market.From the perspective of China, the market structures at home and abroad evolves starting from the perfect competition in different ways： the international rare-earth market is evolving to monopoly and then to competition;the domestic market is evolving to monopoly.Intergrating both domestic and international markets into together, we have four market combinations： ① international and domestic market structures are in competition;② the international market structure is in monopoly and domestic market structure is completely competitive;③ international and domestic market structures are in monopoly;④ the international market structure is completely competitive and domestic market is in monopoly.We found that under market combination.When international and domestic market structures are completely competitive, the optimal exploitation rate of rare earth is the highest;under market combination ③ when the domestic and international markets are monopolized, the optimal exploitation rate of rare earth is lowest.Under the other two kinds of market conditions of ② and ④, the optimal exploitation rates of rare earth are in the middle.When the export volume of rare earth is more than the domestic consumption, the optimal exploitation rate of rare earth under combination ④ is larger than that under combination ②.When the domestic market share is more than the international market share, the optimal exploitation rate of rare earth is larger in condition ② than that in condition ④.