2.2. The market price approach
In wetland, many researches used the market price method to estimate direct use value. In Vietnam,
Tuan also applied this method for a wetland case study in Thua Thien Hue province [4]. The direct use
values from local households include aquaculture, agricultural products, and sea grasses collection. In
addition, on the coast not only direct use value from wetlands but also other direct values sources were
taken into considerations such as: labor hire, handicraft, livestock raising, tourism services, and
cultivation. Market prices are utilized to calculate the generated gross income when the products are sold
in the market. In this research, we used the market price method to compare the differences in direct use
values between the two communes. This research analyzed the direct use values in the coastal zone
derived from aquaculture which is a key economic activities currently occurring in the coastal districts of
Hai Phong. However, due to time and budget constraints, this research does not include indirect use value
and non-use values of the coastal wetlands.
In this research, we assessed direct use value of aquaculture [6] for two coastal communes based on
various criteria [4]:
Cost of production (C) refers to the sum of the costs that households paid in order to obtain
aquaculture. These costs include direct cost (DC) and cost of borrowing money i: C = DC + i
The former costs, which households paid in cash, were for purchasing material, breeding shrimp and
fish annual pond maintenance, labor hire, taxes, and other cost, were based on market prices (in the year
2010: 1$ = 18,000 VND).