Table 1.

List of assessment methods.

List of Assessment Methods
Types	Main Equations	Meaning of Variables
Market value method	$S_1={\displaystyle \sum _{i=1}^n}{P}_i\times \Delta R$	S1 is the economic loss of environment quality; P is the market price of good i; ΔR is the yield reduction of good i that caused by pollution and ecological damage.
Opportunity cost method	$S_2=V_2\times W_2$	S2 is the opportunity cost of the loss; V2 is the Unit opportunity cost of the certain resource; W2 is the amount of resources being polluted or damaged.
Engineering cost method	$S_3=V_3\times Q$	S3 is the cost of prevention and controlling pollution or destruction; V3 is the unit costs of protecting, restoring or replacing the original environmental functions; Q is the unit costs of protecting, restoring or replacing the original environmental functions;