Abstract:

Plant data were collected in Spring and Fall 2013 in paired oiled/unoiled sites in three regions of coastal Louisiana. Live and dead plant biomass for individual species, total living and dead plant biomass per site, canopy height, and estimated percent cover were measured in quadrats placed 1 and 10 m from the marsh edge at three transects perpendicular to shore at each site. Sites were sampled once in the spring (April and May) and once in the Fall (October, November, and December). This dataset coincides with benthic infauna and mussel and snail collections to determine those factors most important in influencing benthic communities and intertidal marsh invertebrate distributions.

Suggested Citation:

Rabalais, Nancy. 2016. Above ground plant biomass, canopy height and estimated percent cover supporting marsh and subtidal benthic community and marsh invertebrate distribution studies in paired oiled/unoiled sites in coastal Louisiana in Spring and Fall 2013. Distributed by: Gulf of Mexico Research Initiative Information and Data Cooperative (GRIIDC), Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7X34VD2

Purpose:

To determine those factors most important in influencing benthic and intertidal marsh invertebrate communities in paired oiled/unoiled sites.

Data Parameters and Units:

Attribute_Label: Site Attribute_Definition: Producer defined name of general location sampled (GI*= W Barataria Bay, N of Grand isle; PS*= E Barataria, Bay Jimmy, Port Sulphur area; TB*= Terrebonne Bay) Attribute_Label: Hypothesized Site Exposure Type Attribute_Definition: Producer defined classification of the site at the beginning of the project, in regards to possible Macondo oil exposure Attribute_Label: Transect # Attribute_Definition: Identifier for individual transects established within each study site Attribute_Label: Distance from marsh edge (m) Attribute_Definition: Distance from edge into marsh where samples were collected (1m = edge, 10 m = interior) Attribute_Label: LAT (decimal degrees) Attribute_Definition: Latitude of each transect in decimal degrees Attribute_Label: LONG (decimal degrees) Attribute_Definition: Longitude of each transect in decimal degrees Attribute_Label: Date Collected Attribute_Definition: Date samples were collected Attribute_Label: Sa live (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of live Spartina alternaflora Attribute_Label: Sa dead (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of dead Spartina alternaflora Attribute_Label: Sa total (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of total Spartina alternaflora Attribute_Label: Jr live (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of live Juncus roemerianus Attribute_Label: Jr dead (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of dead Juncus roemerianus Attribute_Label: Pv live (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of live Philoxerus vermicularis Attribute_Label: Pv dead (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of dead Philoxerus vermicularis Attribute_Label: Ds live (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of live Distichlis spicata Attribute_Label: Ds dead (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of dead Distichlis spicata Attribute_Label: Sp live (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of live Spartina patens Attribute_Label: Sp dead (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of dead Spartina patens Attribute_Label: Sm live (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of live Scirpus maritimus Attribute_Label: Sm dead (dry wt, g/m2) Attribute_Definition: Unit expressing the biomass of dead Scirpus maritimus Attribute_Label: total live (dry wt, g/m2) Attribute_Definition: Unit expressing the total live biomass of all vegetation Attribute_Label: total dead (dry wt, g/m2) Attribute_Definition: Unit expressing the total dead biomass of all vegetation Attribute_Label: total (dry wt, g/m2) Attribute_Definition: Unit expressing the total live and dead biomass of all vegetation Attribute_Label: canopy ht (cm) Attribute_Definition: Unit expressing the canopy height of the plot in cm Attribute_Label: % cover Attribute_Definition: Unit expressing the percent cover in the plot

Methods:

Marsh plants were surveyed in 0.5 x 0.5 m (0.25 m2) quadrats placed 1 and 10 m from the marsh edge at three transects perpendicular to shore at oiled-unoiled plots in three regions of coastal Louisiana. Within each quadrat, species were identified, % cover was estimated for each species, and average canopy height (cm) was measured. We then clipped all the aboveground biomass and collected it in labeled garbage bags. Garbage bags were stored in a walk-in freezer at the lab. Aboveground clippings from the quadrats were sorted by hand, separated by species and live/dead stems, and placed in labeled and tared large paper bags. These bags were allowed to dry in the lab at room temperature, while sets of 8-12 were placed in the drying oven at 60° C. Dry weights were recorded for each bag to get plant biomass (g m2).

Individual Files: