DOI: 10.5061/dryad.95x69p8tf
title: Leaf litter capture in the carnivorous pitcher plant, <em>Sarracenia purpurea</em>: a preliminary study

description: Diet breadth is a key life-history trait influencing range size,
 evolutionary trajectories, and ecosystem functioning. While diet breadth
 studies have traditionally been confined to animals, carnivorous plants
 provide an exciting conceptual extension to existing theory. We examine
 the possibility of diet breadth expansion in Sarracenia purpurea, a
 carnivorous pitcher plant, integrating field and greenhouse experiments
 with CHN analysis to quantify leaf litter consumption. Wild plants
 captured leaf detritus at levels comparable to insect prey. Pitchers fed
 leaf biomass in the field exhibited non-significant increases in foliar
 nitrogen, while the greenhouse experiment showed no effect of leaf litter.
 These results show that S. purpurea pitchers capture a substantial amount
 of leaf litter, but there is no clear evidence of nitrogen assimilation
 from this material. We found that short-term nitrogen acquisition from
 captured litterfall is minimal or absent in S. purpurea pitchers,
 especially relative to rapid nutrient assimilation from arthropod prey.
description: This dataset describes the capture, digestion, and utlization of
 leaf litter by the carnivorous pitcher plant <em>Sarracenia
 purpurea</em>. It includes observational data on the incidence of
 leaf litter within wild <em>S. purpurea </em>pitchers over
 time, ammonia measurements quantifying the release of nitrogen from leaf
 litter and insect prey into pitcher fluids, and percent foliar nitrogen
 and carbon measurments of pitchers experimentally fed leaf litter or
 insect biomass in both field and greenhouse contexts. It also includes
 <em>S. purpurea </em>growth metrics (rosette diameter, pitcher
 number, leaf senescence) and inquiline survivorship data as a response to
 experimental diet treatments. Fluid ammonia levels were measured using
 0-6.0 mg/L Ammonia Test Strips (Hach, Loveland, Colorado, United States),
 and nitrogen and carbon concentrations were measured using CHN combustion
 analysis.
description: # Leaf litter consumption as evidence for diet breadth expansion in the
 broad-ranged carnivorous plant, Sarracenia purpurea
 [https://doi.org/10.5061/dryad.95x69p8tf](https://doi.org/10.5061/dryad.95x69p8tf) ## Files Raw data files: * **Observational_results.csv** -- The sorted/massed prey contents and foliar nitrogen and carbon concentrations (%) in the pitchers sampled during the observational field study. * **Obs_longitudinal.csv** -- The weekly counts of different pitcher content items captured during the longitudinal observational field study. * **Vitro_results.csv** -- The diet treatment and fluid ammonia measures for the in vitro model pitchers (small glass vials). * **Vivo_CHN_duplicates_data.csv** -- The percent foliar nitrogen and carbon of pitcher samples from the in vitro field experiment, measured in duplicate using CHN combustion analysis. * **Vivo_Metadata.csv** -- The diet treatments and notes for the pitcher plants used in the in vivo field experiment. * **Greenhouse.csv** -- The percent foliar nitrogen and carbon, diet treatments, plant morphology, and growth metrics for the pitchers used during the in vivo greenhouse experiment. ## Code: ***Leaf_litter_Sarracenia_purpurea.R*** -- Code for data cleaning, analysis, and plot construction for all experiments in the study.(In Zenodo) ## Glossary of terms: #### ***Observational\_results.csv*** * pitcher_ID -- unique plant ID for each plant sampled (one pitcher leaf was sampled on each individual plant) * other_biomass -- all non-plant biomass (in grams) present inside the sampled pitcher, including insect prey and living inquilines * plant_biomass -- all dead plant biomass (in grams) present inside the sampled pitcher * livep_biomass -- all live plant biomass (in grams) present inside the sampled pitcher (some pitchers contained living aquatic plants, such as Lemna spp. or Utricularia spp.) * %nitrogen -- CHN combustion analysis result: the % foliar nitrogen within the sampled pitcher leaf tissues * %carbon -- CHN combustion analysis result: the % foliar carbon within the sampled pitcher leaf tissues #### ***Obs\_longitudinal.csv*** * plantID -- unique plant ID for each individual plant (collected prey from 1 leaf per plant) * date -- sample collection date in the format month/day/year * leaf:seed -- counts of plant material; some plant material is subdivided into more specific categories * no_fluid -- 1 indicates pitcher was empty of fluid, making prey capture impossible * damage -- 1 indicates pitcher was damaged, preventing fluid accumulation * mL -- number of mL of water accumulated in control tubes of water (50mL falcon tubes) left in the bog * Arthropods -- counts of all arthropod prey #### ***Vitro\_results.csv*** * tube_ID -- unique ID for each model pitcher (a glass tube) to which a diet treatment was applied * treatment -- diet treatment applied to the glass tubes: X = control treatment (no addition), P = plant treatment (90mg dried leaf litter added), I = insect treatment (two adult blue bottle flies added) * ammonia -- ammonia levels (ppm) measured using test strips, 4 weeks after treatment application. NA = vials that were voided and ammonia level wasn't measured (tubes 22 and 23). #### ***Vivo\_CHN\_duplicates\_data.csv*** * pitcher_ID -- unique plant ID for each plant sampled (one pitcher leaf on each individual plant was given an experimental diet treatment and sampled for CHN combustion) * replicate -- the CHN combustion replicate number (either duplicate 1 or 2) * Well -- the position of each sample in the 96-well plate for the CHN analyzer * N -- percent foliar nitrogen in the pitcher tissue sample * C -- percent foliar carbon in the pitcher tissue sample #### ***Vivo\_Metadata.csv*** * plant_ID -- unique plant ID for each plant sampled (one pitcher leaf on each individual plant was given an experimental diet treatment and sampled for CHN combustion) * treatment -- diet treatment applied to the wild pitchers: X = control treatment (no addition), P = plant treatment (90mg dried leaf litter added), I = insect treatment (two adult blue bottle flies added) * emptied -- whether the fluid/contents of the pitcher were emptied at some point during the experimental period (yes/no) * Notes -- notes about each pitcher during the experimental period, including information about how some pitchers were emptied #### ***Greenhouse.csv*** Across all columns, "NA" = Not applicable * plantID -- unique plant ID for each plant sampled * treatment -- diet treatment applied to the greenhouse pitchers: X = control treatment (no addition), P = plant treatment (20mg dried leaf litter added) * diameter -- the diameter (cm) of each plant's rosette, measured at the widest point, at the start of each round (final diameter of round 1 is the starting diameter of round 2) * matLeaf -- the number of mature (open, non-senesced) pitchers on each plant at the start of each round (final number of mature pitchers in round 1 is the starting number in round 2) * youngLeaf -- the number of young (still psittacina shaped) pitchers on each plant at the start of each round (final number of young pitchers in round 1 is the starting number in round 2) * inqOrderMay -- the order (1-24) in which inquilines were added to the round 1 pitchers on May 25th (this was done to control for selecting inquilines of a particular size) * inqOrderJune -- the order (1-24) in which inquilines were added to the round 1 pitchers on June 28th (this was done to control for selecting inquilines of a particular size) * brown2023.06.08 -- the recorded senescing of the round 1 experimental pitchers on June 8th (0 = no browning, 1 = some browning) * brown2023.06.23 -- the recorded senescing of the round 1 experimental pitchers on June 23rd (0 = no browning, 1 = some browning) * brown_harvest -- the recorded senescing condition of the round 1 experimental pitchers during harvest (July 22nd) * harvest_order -- the order (1-24) in which experimental pitchers were harvested at the end of round 1 * notes -- miscellaneous notes about the experimental pitchers/plants during round 1 and 2 * round -- the round (1 or 2) of diet treatments * diameter_final -- the diameter (cm) of each plant's rosette, measured at the widest point, at the end of each round (final diameter of round 1 is the starting diameter of round 2) * matLeaf_final -- the number of mature (open, non-senesced) pitchers on each plant at the start of each round (final number of mature pitchers in round 1 is the starting number in round 2) * youngLeaf_final -- the number of young (still psittacina shaped) pitchers on each plant at the start of each round (final number of young pitchers in round 1 is the starting number in round 2) * dDiam -- the difference in the diameter (cm) of each plant's rosette between the start and end of each round * dmatLeaf -- the difference in the number of mature pitchers on each plant between the start and end of each round * dyoungLeaf -- the difference in the number of young pitchers on each plant between the start and end of each round * pH -- the final fluid pH of each pitcher (only recorded for round 2) * inqOrderJuly -- the order (1-24) in which inquilines were added to the round 2 pitchers on July 22nd (this was done to control for selecting inquilines of a particular size) * inqOrderSept -- the order (1-24) in which inquilines were added to the round 2 pitchers on September 1st (this was done to control for selecting inquilines of a particular size) * wym_final_live -- the number of living Wyeomyia smithii (mosquito inquilines) in each pitcher at the end of round 2 * wym_final_dead_adult -- the number of dead adult Wyeomyia smithii (mosquito inquilines) in each pitcher at the end of round 2 * wym_final_dead_pupa -- the number of dead pupal Wyeomyia smithii (mosquito inquilines) in each pitcher at the end of round 2 * met_final_live -- the number of living larval Metriocnemus knabi (midge inquilines) in each pitcher at the end of round 2 * met_final_dead -- the number of dead larval Metriocnemus knabi (midge inquilines) in each pitcher at the end of round 2 * brown2023.07.22 -- the recorded condition of the round 2 experimental pitchers at the beginning of the round (July 22nd) * brown2023.09.01 -- the recorded senescing of the round 2 experimental pitchers on September 1st (0 = no browning, 1 = some browning) * nitrogen -- percent foliar nitrogen in the pitcher tissue sample * carbon -- percent foliar carbon in the pitcher tissue sample