DECOMPOSITION OF ALLOCHTHONOUS ORGANIC MATTER IN TROPICAL STREAMS: ROLES OF MICROORGANISMS, AQUATIC INSECTS, DECAPODS, AND FISHES.
Detritivores, as fungi and invertebrates, drive the leaf litter decomposition in most temperate forest streams, with aquatic shredder insects playing a central role comminuting leaf litter. Conversely, tropical streams show low diversity of fungi and aquatic shredder insects while macroconsumers are abundant and diverse. What is the impact of these differences on the pathways of leaf litter decomposition in tropical streams? Here, we synthesized records of leaf litter breakdown to compare the roles of microorganisms, invertebrates and fish on breakdown rates from leaf packages of alder and native species on a wide latitudinal gradient (52 °N - 48.78 °S). Despite the fact that tropical streams have higher temperatures, rates of leaf breakdown by microorganisms in temperate (0.010-0.014 KD) and tropical streams (0.062-0.026 KD) are similar. Aquatic shredder insects had low effect on leaf breakdown in tropical streams (0.022-0.052 KD). Fish and decapods contributed to increase leaf litter decomposition in a 50 to 80% in tropical streams. However their comminuting role on allochthonous matter have no been tested extensively in the tropics, neither if there is a relation between that increasing contribution and decreasing role on decomposition by aquatic insects.
Pavel García Soto (Primary Presenter/Author), University of Wyoming, email@example.com;
Robert Hall ( Co-Presenter/Co-Author), University of Wyoming, BHall@uwyo.edu;