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Abstract Pulses of resource availability along environmental gradients can filter the local and regional distribution of macrophyte and microbial mat communities in wetlands. Wetlands that experience short hydroperiods (i.e., <6 months with standing water) may cause macrophyte and microbial mat competition for water. However, the stress gradient hypothesis predicts that abiotic stress should increase facilitative co‐regulation of producer dynamics. To determine if and how macrophyte and microbial mat biomass covary along a hydrologic gradient, we conducted two observational surveys and a biomass removal experiment in Everglades National Park, FL, USA. In the survey, macrophyte and microbial mat biomass were measured over a two‐year period across nine hydrologically regulated macrophyte community types to determine drivers of biomass and macrophyte–microbial mat interactions along a hydroperiod gradient (3–8 months) using a structural equation model. In the experiment, the effect of hydrology on the interaction between macrophytes and microbial mats was quantified by measuring the effect of bimonthly removal of macrophyte or microbial mat biomass on the biomass of both communities in plots in wetlands with contrasting hydroperiods (3–6 months). Hydrology and biological interactions influenced macrophyte and microbial mat biomass, with stronger interactions observed in the shortest hydroperiod transect sites dominated bySchoenus nigricansandCladium jamaicense. Along the hydrologic gradient, we found direct negative effects of macrophyte biomass on microbial biomass and vice versa, and a significant positive effect of microbial response to flooding duration on macrophyte biomass. Experimental macrophyte removal in shorter‐hydroperiod wetlands resulted in a significant increase in microbial biomass while microbial mat removal reduced biomass of the dominant macrophyteC. jamaicense. The facilitative effect of microbial mats on macrophyte biomass in shorter‐hydroperiod wetlands may be driven by mats prolonging soil moisture retention due to their desiccation‐resistant structure. Stress‐induced facilitation supported the stress gradient hypothesis across the short‐hydrologic gradient, while competitive interactions were also observed. As climate and human drivers continue altering hydrology in aquatic systems, the type and strength of community interactions will continue to shift and alter distributions across the landscape.
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Macrophyte and microbial mat biomass co-variation along a hydrologic gradient and response to a removal experiment in temporary wetlands Everglades, FL, USA, February 2003 – November 2006
This data package encompasses hydrologic variables, soil depth, hydrologically-regulated macrophyte community types, macrophyte biomass and community structure, and microbial mat biomass that was collected in two observational surveys and one in-situ experimental manipulation in six temporary wetland regions located in the Everglades, FL, USA. The goal of this project was to examine the co-variation in macrophyte and microbial mat biomass along the hydrologic gradient present across wetland regions and to determine the type and strength of interactions occurring between the two communities, which was tested using a biomass (macrophyte or microbial mat) removal experiment. The census observational survey took place at 140 sites from 2003-04-09 to 2004-05-26, which were randomly distributed across the hydrologic gradient present across the six temporary wetland regions. The transect observational survey occurred along six transects and each was deliberately established along the present hydrologic gradient within each region; a total of 254 sites were sampled from 2003-02-19 to 2005-03-04. The experiment took place at three temporary wetland sites with contrasting hydroperiods (3 – 6 months), and four transects were established per site with 24 pairs of control and treatment plots per transect. The removal treatment occurred one year before data collection, and data collection occurred from 2004-06-20 to 2006-11-25. The package includes six datasets, one R code file, and two shape files associated with the R code. Data collection for all datasets is complete. FCE1274_Census_Survey includes hydrologically-regulated macrophyte community type classifications, macrophyte biomass, microbial mat ash-free dry mass, mean soil depth, water depth, mean annual hydroperiod, and vegetation-inferred hydroperiod; each site was sampled once during the survey period and a subset of sites were sampled each year. FCE1274_Transect_Survey includes macrophyte community type classifications, macrophyte biomass, microbial mat ash-free dry mass, mean soil depth, water depth, mean annual hydroperiod, and vegetation-inferred hydroperiod. Each site was sampled once during the survey period; all sites along each transect were sampled before moving to the next transect. FCE1274_Removal_Experiment includes total macrophyte biomass, live macrophyte biomass, dead macrophyte biomass, and live macrophyte stem density within each microbial mat removal control and treatment plot along each transect at all three sites. Microbial mat dry mass, microbial mat ash-free dry mass, microbial mat chlorophyll-a concentration, and microbial mat organic content for each macrophyte removal control and treatment plot along each transect at all three sites are included as well. Data was collected once from each plot during the data collection period, and one pair of macrophyte removal plots and microbial mat removal plots were randomly sampled on a bimonthly basis until all plots had been sampled. FCE1274_Removal_Experiment_Macrophyte_Biomass includes total macrophyte biomass for each macrophyte species found within each microbial mat removal control and treatment plot along each transect at all three sites. Data was collected once from each plot during the data collection period, and one pair of microbial mat removal plots were randomly sampled on a bimonthly basis until all plots had been sampled. FCE1274_Removal_Experiment_Macrophyte_Density includes total macrophyte stem density for each macrophyte species found within each microbial mat removal control and treatment plot along each transect at all three sites. Data was collected once from each plot during the data collection period, and one pair of microbial mat removal plots were randomly sampled on a bimonthly basis until all plots had been sampled. FCE1274_Removal_Experiment_Macrophyte_Codes includes the taxon codes assigned to each macrophyte species identified in the FCE1274_Removal_Experiment_Macrophyte_Biomass and FCE1274_Removal_Experiment_Macrophyte_Density datasets.
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- Award ID(s):
- 2025954
- PAR ID:
- 10643730
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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