资源与环境经济学：Chapter 8.ppt

1、Chapter 13 Renewable Common-Property Resources: Fisheries And Other Species 13.1 Introduction Main contents: Defining what is meant by an efficient allocation of the catch from a fishery. Examining how the market allocates this common-property resource and the past and potential roles for public pol

2、icies in quest for efficient and sustainable management. Showing how the basic analytical principles of fisheries management could be used for the management of other biological population. 13.2 Efficient Allocations 13.2.1 Biological Dimension 13.2.2 Static Efficient Sustainable Yield 13.2.3 Dynami

3、c Efficient Sustainable Yield 13.2.1 Biological Dimension The biological model posits a particular average relationship between the growth of the fish population and the size of the fish population. Figure 13.1 13.2.1 Biological Dimension The natural equilibrium is the population size which would pe

4、rsist in the absence of outside influences. The minimum viable population represents the level of population below which growth in population is negative. A sustainable yield represents the catch level which equals the growth rate of the population. 13.2.1 Biological Dimension The maximum sustainabl

5、e yield is defined as that population size which yields the maximum growth;hence the maximum sustainable yield is equal to this maximum growth and it represents the largest catch that can be perpetually sustained. 13.2.2 Static Efficient Sustainable Yield Is the maximum sustainable yield synonymous

6、with efficiency? The answer is no. Efficiency is associated with maximizing the net benefit from the use of resource. If we are to define the efficient allocation, we must include the costs of harvesting as well as the benefits. Figure 13.2 13.2.3 Dynamic Efficient Sustainable Yield When positive di

7、scount rates are introduced, the efficient level of effort would be increased beyond that suggested by the static efficient sustained yield with a corresponding decrease in the equilibrium population level. 13.2.3 Dynamic Efficient Sustainable Yield Would a dynamically efficient management scheme le

8、ad to extinction of the fishery? If the growth rate is lower than the discount rate, extinction can occur in an efficient management scheme if the costs of extracting the last unit are sufficiently low. 13.3 Appropriability And Market Solutions Consider the allocation resulting from a fishery manage

9、d by a competitive sole owner. A sole owner would have a well-defined property right to the fish. A sole owner would want to maximize his or her profits. Figure 13.3 13.3 Appropriability And Market Solutions Ocean fisheries are typically common- property resources-no one exercises complete control o

10、ver them. What problems arise when access to the fishery is completely unrestricted? 13.3 Appropriability And Market Solutions Free-access resources create two kinds of externalities: A contemporaneous externality An intergenerational externality 13.3 Appropriability And Market Solutions Are free-ac

11、cess resources and common- property resources synonymous concepts? On the one hand, governments can restrict entry On the other hand, informal arrangements among those harvesting the common property resource can also serve to limit access as well. 13.4 Public Policy Toward Fisheries Aquaculture Rais

12、ing the real cost of fishing Taxes Individual transferable quotas The 200-mile limit The economics of enforcement Figure 13.4 Objectives & Requirements: Understand the efficient allocation of fisheries Grasp the meaning of maximum sustainable yield Understand the allocation of fisheries under differ

13、ent property rights Understand the public policy toward fisheries Discussion: Assume that a local fisheries council imposes an enforceable quota of 100 tons of fish on a particular fishing ground for one year. Assume further that 100 tons per year is the efficient sustained yield. Once the 100th ton

14、 has been caught, the fishery would be closed for the remainder of the year. Is this an efficient solution to the common-property problems? Why or why not? Would your answer be different if the 100-ton quota were divided up into 100 transferable quotas, each entitling the holder to catch one ton of fish, and distributed among the fishermen in proportion to their historical catch? Why or why not?