Centro Interdisciplinario de Ciencias Marinas, Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional S/N Col. Playa Palo de Santa Rita, La Paz, B.C.S, Código Postal 23096, Mexico.
Departamento de Biología, Facultad de Ciencias Naturales y Exactas, Grupo de Investigación en Ecología de Estuarios y Manglares, Universidad del Valle, Calle 13 No. 100-00, Ciudad Universitaria Meléndez, Valle del Cauca, Cali, Colombia.
Environ Sci Pollut Res Int. 2022 Sep;29(41):61608-61622. doi: 10.1007/s11356-021-16814-x. Epub 2021 Oct 30.
Mangroves are important ecosystems of tropical and subtropical shorelines. Anthropogenic activity decreases their habitat quality, affecting structural and functional trophic features. We hypothesized that higher levels of anthropogenic intervention generate diversity loss and modify the trophic structure of tropical mangrove fish communities. We compared the taxonomic and isotopic (δC/δN) composition, abundance, trophic position, and isotopic niche of fish communities from three mangrove systems with different anthropogenic intervention levels in the Colombian Pacific. Non-parametric statistical tests and a Bayesian approach were used to analyze data. A total of 1254 specimens belonging to 23 families, 25 genera, and 30 species were identified, presenting higher abundance (821) in moderate anthropogenic intervention level mangrove (Moderate-AIL), with high dominance of one species (Lile stolifera). The low anthropogenic intervention level mangrove (Low-AIL) was the second in abundance (291) but exhibited a greater number of species (23), while the high anthropogenic intervention level mangrove (High-AIL) presented the least abundance (142) and species number (17). The isotopic composition reveals that Moderate and High-AIL mangroves presented enriched C and N compared to Low-AIL (~ 2 to 4 ‰). Mean trophic position (TP) of communities was slightly higher in the more intervened systems (~ 1 to 2 orders of magnitude), as well as in specific species (Centropomus spp.). Isotopic niche width (TA and SEAc) was greater in High-AIL (41.1 and 9.2), more than doubled compared to Moderate-AIL (33.0 and 4.1). In High-AIL isotopic niche width increased, indicating lesser availability of prey and basal resources. The results obtained in this study support the proposed hypothesis and, suggest that anthropogenic intervention modifies diversity and food webs dynamics, affecting the transfer of matter and energy from macrotidal tropical mangroves to coastal ecosystems. However, it is recommended to be careful concluding differences based exclusively on the anthropogenic intervention level, since it is widely documented that mangrove settings also influence the analyzed trophic parameters.
红树林是热带和亚热带海岸线的重要生态系统。人为活动降低了它们的栖息地质量，影响了结构和功能营养特征。我们假设，更高水平的人为干预会导致多样性丧失，并改变热带红树林鱼类群落的营养结构。我们比较了三个红树林系统的鱼类群落的分类学和稳定同位素（δC/δN）组成、丰度、营养位置和同位素生态位，这些系统在哥伦比亚太平洋地区的人为干预水平不同。使用非参数统计检验和贝叶斯方法分析数据。总共鉴定出 1254 个标本，属于 23 个科、25 个属和 30 个种，在中度人为干预水平的红树林（中度-AIL）中丰度较高（821），一种物种（Lile stolifera）占主导地位。低人为干预水平的红树林（低-AIL）的丰度次之（291），但物种数量较多（23），而高人为干预水平的红树林（高-AIL）的丰度最低（142）和物种数量最少（17）。同位素组成表明，与低-AIL 相比，中度和高-AIL 红树林的 C 和 N 更为富集（2 至 4 ‰）。受人为干预较多的系统中，群落的平均营养位置（TP）略高（1 至 2 个数量级），特定物种（Centropomus spp.）也是如此。高-AIL 的同位素生态位宽度（TA 和 SEAc）较大（41.1 和 9.2），比中度-AIL 大两倍多（33.0 和 4.1）。在高-AIL 中，同位素生态位宽度增加，表明猎物和基础资源的可用性减少。本研究的结果支持了提出的假设，并表明人为干预改变了多样性和食物网动态，影响了从大型潮汐热带红树林向沿海生态系统的物质和能量转移。然而，建议在根据人为干预水平得出结论时要谨慎，因为广泛记录表明，红树林环境也会影响分析的营养参数。
