Application of Nested Logitech Model for Ecosystem Services Valuation (Case study: Gavkhony Wetland, Isfahan Province, Iran)

Wetlands as a situ for the growth of native plants, as a habitat for certain species of fish and aquatic birds; and because of their potential economic, cultural and recreational services are valuable heritage and so their protection and conservation is very essential. Mostly due to the absence of wetlands services valuation, the lack of special regulations and no guarantee for these properties, resources and services of wetlands are not utilized appropriately and destructed and evacuated in a free and unrestricted fashion which leads to inefficiency in use. The purpose of this study is the economic valuation of Gavkhony wetland ecosystem attributes, estimation of implicit price for attributes, impact assessment of socio- economic variables such as age, marriage, indigenous, family size and education on willingness to pay (WTP) and analyzing welfare and compensation variation due to variation of hypothetical policy change proposed. The approach being used is choice experiment that is a subset of choice modeling procedure and stated preference method. Data were collected from six different choice experiments provided in questionnaires and filled out by 500 randomly selected households in Isfahan and Varzaneh Cities in the spring and summer of 2013. Each questionnaire contained 72 hypothetical policies, 36 choice sets, 2442 observations and 7327 rows of data. In order to estimate visitors WTP for improving attribute levels for Gavkhony wetland, nested Logitech models and Hausman-acFadden test were used. This procedure was used on the basis of multinomial discrete choice analysis of preferences, Lancaster’s theory of value and the theory of random utility function. The Hausman-Mac-Fadden test results showed that cross elasticity between the first and third option is the same. Thus, these two options were placed in the second nest. Results also showed that the visitors had WTP for preserving forest diversity and vegetation of wetlands and its surrounding; preserve of natural habitats and organisms life of wetland (bird, fish and animals); wetland hygiene (preventing industrial, domestic effluent and water salinity); and increasing the water surface (increasing wetland water inlet). The value estimated for these four aspects correspondingly were 8636, 12584, 11553 and 4740 Rials. Some socio-economic variables such as gender, marriage, age, family expenditure, education and being native have a positive impact on willingness to pay. The Surplus welfare Results showed that in 72 hypothetical policies, option 1 has the most positive welfare and option 5 has the most negative welfare for users of Govkhony wetland. The surplus welfare results based on WTP estimated are providing important tools for policy making.