The ecological agriculture (hereinafter referred to as eco-agriculture) concept has grown rapidly in Taiwan in recent years. More and more successful eco-agriculture projects have thus sprouted up in Taiwan, and so a quantitative evaluation model of such projects becomes critically important for improving public understanding of eco-agriculture and for providing a basis for policy analysis. This research thus proposes a quantitative evaluation model for eco-agriculture and analyzes the empirical data collected. We take four farms that practice eco-agriculture in eastern Taiwan for the estimation of direct benefits by surveying farmers about their revenues and costs of crop yields. To evaluate indirect benefits, we employ the Contingent Value Method (CVM) to investigate the willingness-to-pay (WTP) of users and non-users to support eco-agriculture. Results from the direct benefit estimation indicate that eco-agriculture adoption is unlikely to improve the local livelihoods of farming communities. In terms of indirect benefit estimation, eco-agriculture is beneficial to society, but based on our analysis of the direct benefits, these indirect benefits fail to be transformed into profits, showing that eco-agriculture exhibits positive externalities. This constitutes unavoidable challenges for eco-agriculture to be sustainable if these positive externalities cannot be internalized.

This study was conducted from ecological and economic points of view in the setting of a nature reserve of wetlands in Taiwan. The ecological data (including area, habitat and ornithological diversity, and ornithological rarity, population size, and representativeness) of 28 wetlands in Taiwan were collected, and " factor analysis " was used to regroup those attributes. The four common factors are rarity, area, representativeness, and diversity, with 36% , 36%, 15% , and 13% relative importance, respectively. A mix index is defined as the weighted average of these four factors. The ecological evaluation method and the results were intro duced to the dichotomous choice with follow-up (DCF) contingent valuation questionnaire. Cameron's expenditure function model and maximum likelihood estimation for DCF data provided by Alberini et al. were used to estimate willingness to pay values for the residents of Taiwan. The results indicate that some ecological factors are statistically significant, which shows the importance of combining ecological valuation and economic evaluation. The estimated median annual willingness to pay is NT$1069.52 with the exchange rate of US$l =; NT$34.5.