lalaja {isotracer}

Dataset for nitrogren fluxes in a Trinidadian mountain stream (Collins 2016)

Description

Dataset built from the article "Fish introductions and light modulate food web fluxes in tropical streams: a whole-ecosystem experimental approach” by Collins et al. (2016).

Usage

lalaja

Format

Tibble with columns

stream

Stream identity. It is always "UL" (for "Upper lalaja") in this dataset. See the model trini_mod also shipped with the package for the full dataset from the original Collins et al. study, including data from the Lower Lajaja stream.

transect

Transect identity. Three transects were sampled downstream of the drip location: c("transect.1", "transect.2", "transect.3").

compartment

Foodweb compartments. Eight compartments are included in this dataset: "NH4", dissolved ammonium; "NH3", dissolved nitrate; "epi", epilithon (primary producers growing on the surface of rocks on the stream bed); "FBOM", fine benthic organic material; "tricor", Tricorythodes (invertebrate); "pseph", Psephenus (invertebrate); "petro", Petrophila (invertebrate); "arg", Argia (invertebrate).

mgN.per.m2

Size of compartment, in mg of nitrogen per m2.

prop15N

Proportion of 15N nitrogen in a compartment nitrogen pool (i.e. 15N / (15N + 14N)).

time.days

Sampling time, in days.

Details

In the original study, 15N-enriched ammonium was dripped into two mountain streams in Trinidad (Upper Lalaja stream and Lower Lalaja stream) and samples of the different foodweb compartments were taken during the drip and after the drip in several transects in each stream. The transects were located at different locations downstream of each drip. There were three transects per stream. The drip phase lasted 10 days, and the post-drip phase lasted 30 days. The complete dataset from the original study is available in the trini_mod model shipped with the isotracer package.

The lalaja dataset is a subset of the full dataset and is used for illustrative purpose in the "Trinidadian streams" case study, which is part of the documentation of isotracer. It contains only the data for the Upper Lalaja stream, and for some but not all of the foodweb compartments.

For more details about the dripping regime and how to use this dataset in a network model, one should refer to the case study in the isotracer package documentation.

Source

This network model contains data from the original article: Collins, Sarah M., Steven A. Thomas, Thomas Heatherly, Keeley L. MacNeill, Antoine O.H.C. Leduc, Andrés López-Sepulcre, Bradley A. Lamphere, et al. 2016. “Fish Introductions and Light Modulate Food Web Fluxes in Tropical Streams: A Whole-Ecosystem Experimental Approach.” Ecology, <doi:10.1002/ecy.1530>.

This dataset was also used in the paper: López-Sepulcre, Andrés, Matthieu Bruneaux, Sarah M. Collins, Rana El-Sabaawi, Alexander S. Flecker, and Steven A. Thomas. 2020. “A New Method to Reconstruct Quantitative Food Webs and Nutrient Flows from Isotope Tracer Addition Experiments.” The American Naturalist 195 (6): 964–85. <doi:10.1086/708546>.