Case Studies - Coastal Lagoons: Ecosystem Processes and Modeling for Sustainable Use and Development - page 465

(WTP) for the wastewater treatment system that would improve future water quality
in the area. In this survey, the evaluation question consists of two steps:

• The respondents were first asked whether they would vote in favor of

making an extra payment in support of the operation of the wastewater
treatment plant.

• Those in favor were asked whether they would accept the bid amount.

The common techniques for asking CV questions are iterative bidding, payment
cards, and dichotomous choice. The single-bounded dichotomous choice approach
was preferred. In this technique, the item being evaluated and the hypothetical market
for this item are described to respondents, who are then asked to state whether they
accept or reject a single “take-it-or-leave-it” offer for the item being evaluated. As
the first step, a pretest was applied for each town on the first day of the CV survey.
After the feedback from the pretest, the questions were revised. The opinions of the
people in each town were better understood during the pretest—they were aware of
the importance of pollution and environmental values. A total of 400 households from
each town (800) replied to the questionnaire.
All the questionnaires were entered into a database using the SPSS software.
After the completion of data transfer, as a first step the data were sorted by removing
“protest responses” given by individuals, who for one reason or another rejected the
hypothetical scenario and refused to give meaningful answers. 38 Afterward, the
survey was analyzed according to the methods explained below.
This kind of survey is typically analyzed in three increasingly sophisticated
ways. First, analysts examine the frequency of distribution of the responses to the
evaluation questions. Second, analysts look at cross-tabulations between WTP
responses and such variables as socio-economic characteristics of the respondent
and attitudes toward the environment. Third, analysts use multivariate statistical
techniques to estimate a valuation function that relates the respondent's answer to
socio-economic characteristics of the respondent and attitudes toward the environ-
ment. The types of statistical procedures utilized depend on whether the respondent
answered a direct, open-ended, valuation question (asking the respondent a direct
question about the most he or she would be willing to pay for the good or service)
or a yes/no question.

9.5.1.2.8 Discussions on Evaluation of Tools
The Koycegiz-Dalyan Lagoon system is a very complex and complicated system,
composed of channels and lakes. Satisfactory evaluation of such a system for sus-
tainable management studies necessitates a large amount of data. Therefore, the field
data should be maintained for a long period and an ecological model should be used
for better understanding of the nutrient dynamics in the system.
Hydrodynamic characterization of the lagoon systems has a vital importance in
nutrient dynamic evaluations. Hydraulic retention times in channels are very low,
i.e., 1 or 2 days. On the other hand, sampling in 16 stations takes more than a few
days for each cruise. Therefore, in order to observe the spatial variations in the
system, it could be even better to take samples simultaneously in the stations along