Toro-Tobón Gabriela, Alvarez-Flórez Fagua, Mariño-Blanco Hernán D, Melgarejo Luz M
Laboratorio de Fisiología y Bioquímica Vegetal, Departamento de Biología, Facultad de Ciencias, Universidad Nacional de Colombia-Sede Bogotá, Carrera 45 #26-85, Bogotá 111321, Colombia.
Plants (Basel). 2022 Jun 29;11(13):1723. doi: 10.3390/plants11131723.
Semi-arid environments characterized by low rainfall are subject to soil desertification processes. These environments have heterogeneous landscapes with patches of vegetation known as resource islands that are generated by nurse species that delay the desertification process because they increase the availability of water and nutrients in the soil. The study aimed to characterize some foliar physiological, biochemical, and anatomical traits of three nurse tree species that form resource islands in the semi-arid environment of La Guajira, Colombia, i.e., , and . The results showed that and have sclerophyllous strategies, are thin (0.2 and 0.23 mm, respectively), and have a high leaf dry matter content (364.8 and 437.47 mg/g). Moreover, both species have a high photochemical performance, reaching Fv/Fm values of 0.84 and 0.82 and PI values of 5.84 and 4.42, respectively. These results agree with the OJIP curves and JIP parameters. Both species had a compact leaf with a similar dorsiventral mesophyll. On the other hand, has a typical succulent, equifacial leaf with a 97.78% relative water content and 0.81 mm thickness. This species had the lowest Fv/Fm (0.73) and PI (1.16) values and OJIP curve but had the highest energy dissipation value (DIo/RC).
以低降雨量为特征的半干旱环境容易发生土壤荒漠化过程。这些环境具有异质景观，有被称为资源岛的植被斑块，这些资源岛是由保护物种形成的，它们通过增加土壤中水分和养分的可用性来延缓荒漠化过程。该研究旨在描述在哥伦比亚瓜希拉半干旱环境中形成资源岛的三种保护树种的一些叶片生理、生化和解剖特征，即[具体树种1]、[具体树种2]和[具体树种3]。结果表明，[具体树种1]和[具体树种2]具有硬叶策略，叶片较薄（分别为0.2和0.23毫米），叶片干物质含量高（分别为364.8和437.47毫克/克）。此外，这两个物种都具有高光化学性能，Fv/Fm值分别达到0.84和0.82，PI值分别达到5.84和4.42。这些结果与OJIP曲线和JIP参数一致。这两个物种的叶片紧凑，具有相似的异面叶肉。另一方面，[具体树种3]具有典型的肉质、等面叶，相对含水量为97.78%，厚度为0.81毫米。该物种的Fv/Fm（0.73）和PI（1.16）值以及OJIP曲线最低，但能量耗散值（DIo/RC）最高。
