10.5061/DRYAD.7GR50
Recalde Ruiz, Fátima Carolina
State University of Campinas
Postali, Thaís Cifuentes
State University of Campinas
Romero, Gustavo Q.
State University of Campinas
Data from: Unravelling the role of allochthonous aquatic resources to food
web structure in a tropical riparian forest
Dryad
dataset
2016
ecosystem boundaries
flux across ecosystems
Food web structure
2016-11-12T00:00:00Z
2016-11-12T00:00:00Z
en
https://doi.org/10.1111/1365-2656.12475
8487 bytes
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CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
1. The role of matter and energy flow across ecosystem boundaries for
subsidized consumer populations is well known. However, little is known on
the effects of allochthonous subsidies on food web structure and trophic
niche dimensions of consumers in the tropics. 2. We excluded allochthonous
aquatic insects from tropical streams using greenhouse-type exclosures to
test the influence of aquatic allochthonous subsidies on the trophic
structure and niche dimensions of terrestrial predators using stable
isotope methods. 3. In exclosure treatments, abundance and biomass of
terrestrial predators, and biomass of phytophages, decreased and
increased, respectively. Vegetation-living predators were more responsive
to allochthonous inputs than those living on the ground. Overall, lower
availability of allochthonous inputs did not affect community-wide metrics
and niche width of predators. However, the niche width of some spider
families had very low overlap between treatments, and others had wider
isotopic niches in the control than exclusion treatment. Most of the C and
N in predators living in control stretches came from aquatic subsidies,
and those predators living in exclusion treatments switched their diets to
terrestrial sources, showing a preference of predators for allochthonous
subsidies. 4. Our results suggest that allochthonous subsidies are also
relevant to tropical fauna living upon vegetation. Moreover, allochthonous
resources may amplify the niche dimension of certain predators, or
considerably change the trophic niche of others. Our study highlights the
importance of including modern isotopic tools in elucidating the role of
allochthonous resources on the patterns of trophic structure and niche
dimensions of consumers from donor ecosystems.
Abundance and Biomass of trophic guilds