产业关联与地理集聚——对煤电产业基地的一个新经济地理学解释

Industrial link and geographic agglomeration:An explanation on coal and electricity base by new economic geography

本文借鉴新经济地理学研究集聚现象的资源禀赋、规模经济和运输成本等关键概念,建立寡头垄断模型下的空间集聚机制,同时考虑产业之间的纵向关联和企业之间的策略性互动关系,借助博弈论分析,来解释煤电产业基地的地理集聚现象。得出以下几点结论:第一,在不存在规模效应、运输成本和要素禀赋差异的情况下,煤电企业不会产生地理上的集聚。第二,逐步放开这些条件就会发现,要素禀赋差异引发了煤炭产业的空间集聚现象;规模效应加剧了煤炭企业的地理集聚。第三,当运输成本不存在时,煤炭产业的集聚不会引发相应的电力产业集聚,但是只要存在运输成本,即使运输成本很小,电力企业也会发生迁移从而集聚。可见,考虑了运输成本,煤炭企业的集聚带动了电力企业的集聚。第四,若考虑两地区煤炭企业存在技术上的差异,在不存在规模效应、运输成本和资源禀赋差异的情况下,西部地区煤炭企业将向东部集中。第五,在不存在运输成本和规模效应,但资源禀赋存在差异的条件下,煤炭企业在东西部地区的聚散取决于技术进步和资源禀赋差异带来的成本权衡。

Using key concepts such as resource endowment,scale economy and transportation cost and applying them to agglomeration from new economic geography,I establish spatial agglomeration mechanisms based on oligopoly modeling,taking into account vertical links between industries and strategic interaction between firms. I found that without scale economy,transport cost and factor endowment differences,electricity firms can buy required coal at the same price from different coal firms and coal firms can offer the same wage for labor,so labor migration does not happen. In other words,coal and electricity firms will not cluster geographically. Without these restrictions,we will find that factor endowment differences spark an agglomeration phenomenon of the coal industry;scale economy exacerbates geographic cluster of coal industry.When transport costs do not exist,the coal industry cluster will not lead to corresponding concentration of electricity firms,but as long as transportation costs exist,migration of electricity firms also occurs. Visibly,considering transportation costs,coal firm's agglomeration brings about the concentration of electricity firms. In addition,considering difference between coal firms' technologies in two regions,without scale economy,transport costs and factor endowment differences,coal firms in the western region will be concentrated to the eastern region. But under the condition of bypassing transportation costs and the scale economy and considering differences in resource endowments between coal firms in eastern and western regions,clustering or scattering of coal firms in eastern and western regions depends on trade-offs between technological progress and resource endowment difference. Even relaxing these hypotheses,clustering or scattering of coal firms just be affected by more complex trade-offs between several costs.