Nutrient- and sediment-induced macroinvertebrate drift in Honduran cloud forest streams
- First Online:
- Cite this article as:
- O’Callaghan, P., Jocqué, M. & Kelly-Quinn, M. Hydrobiologia (2015) 758: 75. doi:10.1007/s10750-015-2271-8
Montane cloud forests are hydrologically unique, critically endangered ecosystems and frequently major sources of potable water, which have come under increasing pressure from human activities. It is therefore of vital importance that our understanding of the effects of anthropogenic stressors on the aquatic biota in these ecosystems is improved. To this end, a series of flow channel-based field experiments was performed to quantify the effects of nutrient enrichment and deposited fine sediment (two stressors commonly observed in tropical regions) on river macroinvertebrate assemblages in a cloud forest park in Honduras. Macroinvertebrate communities responded to the addition of nutrients (released from struvite) through an increased percentage abundance drifting and to elevated sediment levels with an increased percentage abundance and richness drifting in the first 24 h following treatment. A shift in community structure was also observed in response to elevated nutrients with lower abundances of some taxa and an overall decrease in richness. Our results indicate that increased nutrient loading and sedimentation can alter benthic macroinvertebrate community composition in high-altitude neotropical streams. Macroinvertebrate communities may be impacted via direct toxicity of nutrients and clogging of interstitial spaces and/or reductions in refugia due to sedimentation.