Disentangling the environmental determinants of tropical biomes is crucial for understanding their response to climate change. This study investigated the effect of climate and soil-related variables on biome transitions in the Caribbean region of Colombia and Panama, focusing on xerophytic forest (XF), tropical dry forest (TDF), and tropical rainforest (TRF). We analyzed the climatic variables at different time scales (daily, seasonal, and annual) and their interaction with soil properties. We performed an ordinal logistic regression to assess the combined effect of the most important variables in biome transitions. Our results showed that climate variables are major discriminators in our study region, particularly precipitation at a seasonal and annual scale. The ordinal logistic regression highlighted the significance of annual precipitation and dry-season length in biome transitions, with maximum temperature impacting TDF-TRF transitions. Soil differences, although present (e.g., higher sand content in XF), played a marginal role. Overall, our findings emphasize the dominance of climate over soil in shaping tropical biome distributions in the northern Caribbean part of South America. These findings contribute to a deeper understanding of tropical biome responses to climate change.

中文翻译：

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气候变量对哥伦比亚和巴拿马加勒比地区生物群落过渡的影响


解开热带生物群落的环境决定因素对于了解它们对气候变化的反应至关重要。本研究调查了气候和土壤相关变量对哥伦比亚和巴拿马加勒比地区生物群落过渡的影响，重点关注旱生林 （XF）、热带干旱森林 （TDF） 和热带雨林 （TRF）。我们分析了不同时间尺度（每日、季节性和每年）的气候变量及其与土壤特性的相互作用。我们进行了顺序 logistic 回归，以评估生物群落转换中最重要变量的综合影响。我们的结果表明，气候变量是我们研究区域的主要判别因素，尤其是季节性和年度尺度的降水。顺序 logistic 回归强调了年降水和旱季长度在生物群落转变中的重要性，最高温度会影响 TDF-TRF 转变。土壤差异虽然存在（例如，XF 中的沙子含量较高），但起着边际作用。总体而言，我们的研究结果强调了气候对土壤的主导地位，它塑造了南美洲北加勒比地区的热带生物群落分布。这些发现有助于更深入地了解热带生物群落对气候变化的反应。