Benthic community structure and ecosystem functions in above- and below-waterfall pools in Borneo

Abstract

Waterfalls are geomorphic features that often partition streams into discrete zones. Our study examined aquatic communities, litter decomposition and periphyton growth rates for above-and belowwaterfall pools in Ulu Temburong National Park, Brunei. We observed higher fish densities in belowwaterfall pools (0.24 fish m -2 vs. 0.02 fish m -2 in above-waterfall pools) and higher shrimp abundance in above-waterfall pools (eight shrimp/pool vs. less than one shrimp/pool in below-waterfall pools). However, macroinvertebrate densities (excluding shrimp) were similar among both pool types. Ambient periphyton was higher in below-waterfall pools in 2013 (4.3 vs. 2.8 g m -2 in above-waterfall pools) and 2014 (4.8 vs. 3.4 g m -2 in above-waterfall pools), while periphyton growth rates varied from 0.05 to 0.26 g m -2 days -1 and were significantly higher in below-waterfall pools in 2014. Leaf litter decomposition rates (0.001 to 0.024 days -1 ) did not differ between pool types, suggesting that neither shrimp nor fish densities had consistent impacts on this ecosystem function. Regardless, this research demonstrates the varied effects of biotic and abiotic factors on community structure and ecosystem function. Our results have highlighted the importance of discontinuities, such as waterfalls, in tropical streams.

Effects of changes in isotopic baselines on the evaluation of food web structure using isotopic functional indices

“…4 ) were reported suggesting that the analyzed organisms occupied similar trophic positions in the food webs ( Cabana & Rasmussen, 1996 )) and might therefore feed on similar diets above and below the waterfall sites. Therefore, in our study, waterfalls did not significantly impact the food web structure of invertebrate communities, and these results could strengthen previous findings showing the absence of major effect of waterfall on invertebrate community composition in four tropical rivers ( Baker et al, 2016 ).…”

New species of Indocloeon Müller-Liebenau from South-East Asia (Ephemeroptera, Baetidae)

“…The specimens were collected by Kate Baker (King’s College London, UK) in the Ulu Temburong National Park in Brunei Darussalam with surber and kick-sampling methods (Baker et al 2016a, b, 2017a, b) and by Michael Balke (Zoologische Staatssammlung München, ZSM, Germany) on the islands of Flores, Sumbawa, and Timor (Indonesia).…”

Decolonizing field ecology

“…This was the case, for instance, in the research of one of the authors (K.B.) whose collaboration and reliance on local field assistants was not given enough prominence (Baker, Chadwick, Kahar, Sulaiman & Wahab, ; Baker, Chadwick, Wahab & Kahar, ).…”