Department of Production Theory and Resource Economics, Institute of Farm Management, University of Hohenheim, Stuttgart, Germany.
PLoS One. 2021 May 6;16(5):e0251206. doi: 10.1371/journal.pone.0251206. eCollection 2021.
Evidence points to past bee-mediated crop pollination deficits in Chanthaburi province, Eastern Thailand. Conversely, no such evidence has yet been reported for Chiang Mai province (Northern Thailand), suggesting that wild pollination is delivered there above the requirements of local orchards. Discrete choice experiments (DCE) were conducted to elicit the preferences of pollinator-dependent orchard farmers with regard to three pollinator conservation measures and their possible effects on of native bee populations in each region. We fitted random parameter logit (RPL) models on the resulting data to capture preference heterogeneity and to obtain willingness to pay (WTP) point estimates. To test our results' robustness, we also inspected for scale heterogeneity by fitting generalized mixed logit (GMXL) models on the pooled and individual datasets. This yielded WTP space estimates (i.e., directly from WTP distributions) and made possible the comparison of farmers' preferences for a native bee conservation policy in both regions. The results hint at significant WTP differences for some of the conservation policy attributes between both provinces. Furthermore, unobserved contributions to choice seem to have been more random in Chiang Mai. Our analyses also suggest that farmers who engage in bee-related activities are WTP more for a conservation policy that includes bee husbandry.
有证据表明,在泰国东部尖竹汶府,过去蜜蜂介导的作物授粉存在不足。相反,在泰国北部的清迈府,目前还没有发现这种情况,这表明当地果园的野生授粉已经满足了需求。我们进行了离散选择实验(DCE),以了解依赖传粉媒介的果园农民对三种传粉媒介保护措施的偏好,以及这些措施可能对两个地区本地蜜蜂种群的影响。我们对所得数据进行了随机参数对数(RPL)模型拟合,以捕捉偏好异质性,并获得每个地区的支付意愿(WTP)点估计值。为了检验我们结果的稳健性,我们还通过对汇总和个人数据集拟合广义混合对数(GMXL)模型,检查了规模异质性。这产生了 WTP 空间估计值(即直接来自 WTP 分布),并使得可以比较两个地区对保护本地蜜蜂政策的农民偏好。结果表明,这两个省份对一些保护政策属性的 WTP 存在显著差异。此外,选择中的未观察到的贡献在清迈似乎更为随机。我们的分析还表明,从事与蜜蜂相关活动的农民更愿意为包括养蜂在内的保护政策支付更多费用。