Temporal variation of macroinvertebrate diversity in a high Andean microbasin in the south American tropics
Tallennettuna:
| Tekijät: | , , , , , , |
|---|---|
| Aineistotyyppi: | artículo original |
| Tila: | Versión publicada |
| Julkaisupäivä: | 2026 |
| Kuvaus: | Introduction: The study examines the aquatic biodiversity of macroinvertebrates in the Alambi River, in Ecuador and analyzes how human intervention has influenced the physico-chemical composition of the water and macroinvertebrate communities among 2000 and 2021. Methods: Physical and chemical data were collected, and pH, conductivity, dissolved oxygen, dissolved solids, and temperature were measured. The macroinvertebrates were obtained by means of "Surber", "D" and "kick" type nets. Three indices were used: BMWP, (Biological Monitoring Working Party), ABI (Andean Biotic Index) and (EPT) (Ephemeroptera, Plecoptera and Trichoptera). Cluster analysis, principal components and canonical analyses were also performed. Results: Taxonomic diversity increased significantly between 2000 and 2021, with an increase in the entire group of taxa. Diversity indices varied similarly between years, Simpson from 0.82 to 0.89 in 2000 versus 0.74 to 0.85 in 2021. Shannon in 2000 (2.20 to 2.45) and in 2021 (1.93-2.47). The completeness of the sampling was similar in both years, 81 vs 77 %, respectively. The structure of the macroinvertebrate community was more heterogeneous overall in 2021. There is a change in the sequential pattern in the turnover of communities in the direction of flow, which varies in 2021. The width of the river decreased in 2021. The average speed of the river also decreased from 1.12 m/s in 2000 to 0.52 m/s in 2021. The pH of the water increased slightly (7.8 to 8.1). Dissolved oxygen increased significantly from 66 % to 80 %. Conductivity and dissolved solids increased at all stations in 2021. The physico-chemical variables varied in their importance over the years, the most relevant being dissolved oxygen, total solids, and altitude, associated with good quality indicator families. The quality indicators in general demonstrated good watershed quality maintained over time, despite changes in both land use and human population growth. Conclusion: The Alambi basin has important changes in the composition and structure of aquatic invertebrate communities, however, it generally maintains good physical, chemical and biotic conditions that support the processes for maintaining the integrity of the basin. |
| Maa: | Portal de Revistas UCR |
| Organisaatio: | Universidad de Costa Rica |
| Repositorio: | Portal de Revistas UCR |
| Kieli: | Español |
| OAI Identifier: | oai:portal.revistas.ucr.ac.cr:article/119 |
| Linkit: | https://revistas.ucr.ac.cr/index.php/rrbt/article/view/119 |
| Sanahaku: | bioindication macrobenthos biodiversity temporal variation basin analysis bioindicación biodiversidad macrobentos variación temporal análisis de cuenca |