1、农经专业资源与环境经济学 全册完整教学课件3 Chapter 2 Valuing The Environment: Concepts 1. Introduction Main contents: Develop the general conceptual framework used in economics to approach environmental problems. Examining the relationship between human actions, as manifested through the economic system, and the enviro
2、nmental consequences of those actions. Establish criteria for judging the desirability of the outcomes of this relationship. 2. The Human Environmental Relationship 2.1 The Environment as an Asset 2.2 The Economic Approach 2.1 The Environment as an Asset In economics the environment is viewed as a c
3、omposite asset （复合资产）（复合资产） that provides a variety of services. Provides the economy with raw materials and energy Also provides services directly to consumers, such as air, water, amenities, etc. 2.1 The Environment as an Asset If the environment is defined broadly enough, the relationship between
4、 the environment and the economic system can be considered a closed system. A closed system （封闭系统）（封闭系统） is one in which no inputs are received from outside the system and no outputs are transferred outside the system. An open system （开放系统）（开放系统）is one in which the system imports or exports matter o
5、r energy. 2.1 The Environment as an Asset The first law of thermodynamics （热力学（热力学 第一定律）第一定律） The law states that energy and matter cannot be created or destroyed in a closed system. The law implies that the mass of materials flowing into the economic system from the environment has to either accumu
6、late in the economic system or return to the environment as waste. 2.1 The Environment as an Asset The second law of thermodynamics （热力（热力 学第二定律）学第二定律） The law states that entropy （熵） increases. Applied to energy processes, this law implies that no conversion from one form of energy to another is co
7、mpletely efficient and that the consumption of energy is an irreversible process. Also implies that in the absence of new energy input, any closed system must eventually use up its energy. 2.2 The Economic Approach Two different types of economic analysis can be applied to increase our understanding
8、 of the relationship between the economic system and the environment. Positive economics （实证经济学）（实证经济学）attempts to describe what is, what was, or what will be Normative economics （规范经济学）（规范经济学）deals with what ought to be. 3. Normative Criteria for Decision-Making Economists suggest that actions have
9、 both benefits （收益）and costs （成本）. If the benefits exceed the costs, then the action is desirable. If the costs exceed the benefits, then the action is not desirable. If BC, then support the action, otherwise oppose the action If B/C1, support the action otherwise, oppose the action 3. Normative Cri
10、teria for Decision-Making How to measure benefits and costs? 3. Normative Criteria for Decision-Making Benefits （收益）can be derived from the demand curve for the good or service provided by the action. Demand curves （需求曲线）（需求曲线）measures the amount of a particular good people would be willing to purch
11、ase at various prices. Figure 2.2 Figure 2.3 3. Normative Criteria for Decision-Making Measuring total costs （总成本）（总成本）on the same set of axes involves logic similar to measuring total benefits. All costs should be measured as opportunity costs （机会成本）（机会成本）. It is important to stress that environmen
12、tal services have costs even though they are produced without any human input. Total cost is simply the sum of the marginal costs （边际成本）（边际成本）. Figure 2.4 3. Normative Criteria for Decision-Making Since net benefit （净收益）（净收益）is defined as the excess of benefits over costs, it follows that net benefi
13、t is equal to that portion of the area under the demand curve which lies above the supply curve. Figure 2.5 3. Normative Criteria for Decision-Making The analysis we have covered so far is very useful for thinking about actions where time is not an important factor. How can we make choices when the
14、benefits and costs may occur at different points in time? In order to incorporate timing, the decision rule must provide a way to compare the net benefit received in one period with the net benefit received in another. The concept that allows this comparison is called present value （现值）（现值）. 3. Norm
15、ative Criteria for Decision-Making The present value of a one-time net benefits received n years from now is The present value of a stream of net benefits B0,Bn received over a period of n years is computed as 3. Normative Criteria for Decision-Making It is now possible to show how this analysis can
16、 be used to evaluate actions. First calculate the present value （现值） of net benefits （净收益） from the action If the present value is greater than zero, the action should be supported. Otherwise it should not. 4. Finding the Optimal Outcome Three steps proceeded by normative analysis: First we will ide
17、ntify an optimal （最优的） outcome. Second we will attempt to discern the extent to which our institutions produce optimal outcomes and, where divergences occur between actual and optimal outcomes, to attempt to uncover the behavioral sources of the problems. Finally designing appropriate policy solutio
18、ns. Examples: Consider the rising number of depleted ocean fisheries. Depleted fisheries not only jeopardize oceanic biodiversity, but also pose a threat to both the individuals who make their living from the sea and the communities that have depended on fishing to support their local economies. How
19、 would an economist attempt to understand and to resolve this problem? Example: The first step would involve defining the optimal stock （最优存量）or the optimal rate of harvest （最优捕捞率）of the fishery. The second step would compare this level with the actual stock and harvest levels. The third step would
20、reach the solutions. 4.1 Static Efficiency The chief normative economic criterion for choosing among various allocations occurring at the same point in time is called static efficiency （静态效率）（静态效率）. An allocation of resources is said to satisfy the static efficiency criterion if the net benefit from
21、 the use of those resources is maximized （最大化）by that allocation. 4.1 Static Efficiency First Equimarginal Principle (the “Efficiency Equimarginal Principle”)（第一等边际原理）: Net benefits are maximized when the marginal benefits from an allocation equal the marginal costs. Pareto Optimality （帕累托最优）（帕累托最优）
22、: Allocations are said to be Pareto optimal if no other feasible allocation could benefit some people without any deleterious effects on at least one other person. 4.2 Dynamic Efficiency The traditional criterion used to find an optimal allocation when time is involved is called dynamic efficiency （
23、动态效率）（动态效率）. An allocation of resources across n time periods satisfies the dynamic efficiency criterion if it maximizes the present value of net benefits that could be received from all the possible ways of allocation those resources over the n periods. Further reading: A 迈克里 弗里曼，环境与资源价值评 估理论与方法，中国
24、人民大学出版社， 2002 Objectives 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 with efficiency? The answer is no. Efficiency is a
25、ssociated 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 discount rates are introduced, the efficient level o
26、f 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 lead to extinction of the fishery? If the growth rat
27、e 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 managed by a competitive sole owner. A sole owner would
28、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 over them. What problems arise when access to the f
29、ishery 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-access resources and common- property resources syno
30、nymous 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 Raising the real cost of fishing Taxes Individual tran
31、sferable 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 different property rights Understand the public policy t
32、oward 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 has been caught, the fishery would be closed for
33、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 propo
34、rtion to their historical catch? Why or why not? Chapter 14 Economics of Pollution Control: An Overview 14.1 Introduction Main contents: Lay the foundation for understanding the policy approach to controlling the flow of waste products by developing a general framework for analyzing pollution contro
35、l. Define efficient and cost-effective allocations for a variety of pollutant types. Compare the efficient and cost-effective allocations to market allocations. Demonstrate how efficiency and cost-effectiveness can be used to formulate desirable policy responses. 14.2 A Pollutant Taxonomy According
36、to the absorptive capacity of the environment, the pollutants can be classified as follows: Stock pollutants, which the environment has little or no absorptive capacity. Found pollutants, which the environment has some absorptive capacity. 14.2 A Pollutant Taxonomy Pollutants can also be classified
37、by their zone of influence, defined both horizontally and vertically. The horizontal dimension deals with the domain over which damage from an emitted pollutant is experienced. Local pollutants Regional pollutants The vertical zone of influence describes whether the damage is caused mainly by ground
38、-level concentrations of an air pollutant or by concentrations in the upper atmosphere. surface pollutant Global pollutant 14.3 Defining Efficient Allocation of Pollution 14.3.1 Stock Pollutants 14.3.2 Fund Pollutants 14.3.1 Stock Pollutants The efficient allocation of a stock pollutant must take in
39、to account the fact that the pollutant accumulates in the environment over time and that the damage caused by its presence increases and persists as the pollutant accumulates. 14.3.1 Stock Pollutants Suppose: consider the allocation of a commodity which we refers to as X. The production of X involve
40、s the generation of a proportional amount of a stock pollutant. The damage caused by the presence of this pollutant in the environment is further assumed to be proportional to the size of the accumulated stock. 14.3.1 Stock Pollutants The efficient allocation is the one which maximizes the present v
41、alue of the net benefit. In this case the net benefit at any point in time t is equal to the benefit received from the consumption of X minus the cost of the damage caused by the presence of the stock pollutant in the environment. 14.3.1 Stock Pollutants Efficient allocation of stock pollutants: The
42、 damage cost rises with the cumulative amount deposited in the environment. The efficient quantity of X would decline over time as the marginal cost of the damage rises. The price of X would rise over time, reflecting the rising social cost of production. the amount of resources committed to control
43、ling the pollutant would increase over time. Ultimately, a steady state would be reached where additions to the amount of the pollutant in the environment would cease and the size of the stock would stabilize. 14.3.1 Stock Pollutants Technological progress could modify this efficient allocation. The
44、 marginal damage cost associated with a given level of production of X would lower. More of X could be produced with technological progress than without it. 14.3.2 Fund Pollutants The efficient allocation of fund pollutants is represented by the point at which the damage caused by the marginal unit
45、of pollution is exactly equal to the marginal cost of avoiding it. Figure 15.2 14.4 Market Allocation of Pollution The unimpeded market not only fail to generate the efficient level of pollution control but also penalize those firm which might attempt to control an efficient amount because damage co
46、sts are externalities but control costs are not. Hence the case for some sort of government intervention is particularly strong for pollution control. 14.5 Defining A Cost-Effective Allocation Assume: there are two emission sources currently emitting a total 30 units of emission. the environment can
47、 assimilate 15 units, so that a reduction of 15 units is necessary. How should this 15-unit reduction be allocated between the two sources in order to minimize the total cost of the reduction? Figure 15.3 14.5 Efficient Policy Responses One way would be to impose a legal limit on the amount of pollu
48、tion allowed by each emitter. An alternative approach would be to internalize the marginal damage caused by each unit of emissions by means of a tax or charge on each unit of emissions. 14.5 Efficient Policy Responses However, while the efficient levels of these policy instruments can be easily defi
49、ned in principle, they are very difficult to implement in practice for information asymmetry . How can environmental authorities allocate pollution control responsibility in a reasonable manner when the information burdens are apparently so unrealistically large? Cost-effective criterion 14.6 Cost-E
50、ffective Policies For Uniformly Mixed Fund Pollutants 14.6.1 Defining A Cost-effective Allocation 14.6.2 Cost-effective Pollution Control Policies 14.6.1 Defining A Cost-Effective Allocation The cost of achieving a given reduction in emissions will be minimized if and only if the marginal costs of c
