Flora ( IF 1.9 ) Pub Date : 2021-04-18 , DOI: 10.1016/j.flora.2021.151830 Katharine L. Gerst , M. Rasoul Sharifi , Barry Prigge , Philip W. Rundel
Relatively few studies are available to characterize the distribution, abundance and ecophysiology of aroid epiphytes, distinct from aroid hemiepiphytes which are more common and abundant. The rosulate growth form is restricted to a relatively small number of aroid species. Field and experimental growth studies and ecophysiological measurements on rosulate aroids were carried out at La Selva Biological Station in the premontane rainforest of the Atlantic lowlands of Costa Rica. Rosulate aroids occur in habitats from forest understory to high canopy, and from old growth wet forest to secondary forest in Costa Rica. The distribution of rosulate and acaulescent aroid epiphytes were determined in multiple stands of old growth and secondary tropical forests at La Selva. Anthurium upalense and Philodendron wendlandii exhibited a preference for upper canopies on trees over 50 cm dbh where irradiance levels are high for much of the day. Anthurium consobrinum and A. bakeri occurred lower in the canopy in more shaded positions. To evaluate how these habitat preferences are related to plant traits, controlled shadehouse growth experiments were conducted to characterize species response to different ambient light environments. We applied conditions of high light (50% full sun), medium light (10% full sun), and low light (2% full sun) to simulate a gradient of canopy and understory light environments. Anthurium consobrinum and A. bakeri exhibited photosynthetic traits characteristic of shade-adapted understory epiphytes. In contrast, A. upalense and Ph. wendlandii, typically high canopy species, had maximum photosynthetic rates of 10.5 and 8.7 µmol m−2 s−1, respectively, higher than those previously reported for other vascular epiphytes. The variability in distribution of epiphytic aroids in Costa Rican premontane rainforest is consistent with their diversity of ecological and ecophysiological traits demonstrating adaptation to diverse canopy habitats in this aroid growth form.
中文翻译:
哥斯达黎加低地雨林中玫瑰形玫瑰样附生植物的分布和光合吸收
相对较少的研究可用来表征无环类附生植物的分布,丰度和生态生理,这与较常见和丰富的无环半生附生植物不同。玫瑰状的生长形式仅限于相对较少数量的类圆环物种。在哥斯达黎加大西洋低地的山前雨林中的La Selva生物站进行了田野和实验性生长研究以及对玫瑰状拟南芥的生态生理测量。在哥斯达黎加,从林下层到高树冠,从老到的湿润森林到次生林,栖息地都出现了环状的环状小行星。在La Selva的多个老林和次生热带森林中,测定了玫瑰状和硬红藻类附生植物的分布。红掌upalense和Philodendron wendlandii对超过50 cm dbh的树木表现出较高的冠层偏好,该树在一天的大部分时间中辐照度很高。红掌和面包曲霉在较高阴影位置的冠层发生率较低。为了评估这些栖息地的偏好与植物性状之间的关系,进行了受控的遮棚生长实验,以表征物种对不同环境光环境的响应。我们应用了强光(50%的日光),中光(10%的日光)和弱光(2%的日光)的条件来模拟冠层和地下光环境的渐变。红掌和面包表现出阴影适应性地下附生植物的光合特性。与此相反,A. upalense和pH值。wendlandii,通常高篷物种,具有10.5和8.7微摩尔米最大光合速率-2小号-1,分别比前面针对其他血管附生报道的那些更高。哥斯达黎加的山前雨林中附生无环类植物分布的多样性与其生态和生态生理特征的多样性相一致,这表明适应了这种无环类植物生长形式的不同冠层栖息地。