README: Data for: Fire season and time since fire determine AM fungal trait responses to fire management

New Phytologist

Dr. Jacob R. Hopkins, Dr. Thomas Mckenna, and Dr. Alison E. Bennett

Arbuscular mycorrhizal (AM) fungi are common mutualists in grassland and savanna systems that are adapted to recurrent fire disturbance. This long-term adaptation to fire means that AM fungi display disturbance associated traits which be useful for understanding environmental and temporal effects on AM fungal community assembly. In this work, we evaluated how fire driven ecological selection on AM fungal spore traits varies with fire season (Fall vs. Spring) and time since fire. We tested this by analyzing AM fungal spore traits (e.g., colorimetric, sporulation, and size) from a fire regime experiment. Immediately following Fall and Spring fires, spore pigmentation darkened; however, this did not mediate the observed differences between Fall burned and no burn communities. Six months after Fall fires, spores in burned plots were lower in volume, produced less color rich pigment, and had higher sporulation rates, and these differences in spore traits were associated with shifts in AM fungal spore communities. This shows that AM fungal responses to fire vary based on season (stronger effects in the Fall) and with time since fire. Variation in AM fungal responses to fire time may reflect greater exposure to fire in Fall, when sporulation is highest.

spore_communities.csv contains the spore community data from the experiment.

traits_community-level.csv & traits_species-level.csv contain AM fungal spore traits data at the community and species level respectively.

Data and their description

spore_communities.csv:

AM fungal spore community data collected in Spring and Fall 2022 from Lecompton, KS

• plot: field ID for plot
• time: sampling time, fall22=October 2022, spr22=April 2022
• treatment: fire regime treatment (no burn = no fire, annual = annual fire, biennial = biennial fire, triennial = triennial fire)
• fire: occurrence of fire during 2022 (yes = fire, no = no fire)
• season: indicates season of fire (fall = Fall fire, spring = Spring fire)
• column: pertains to field plot location (East/West orientation)
• row: pertains to field plot location (North/South orientation)
• remaining columns (H through Y): denote spore frequencies for each AM fungal species

traits_community-level.csv:

AM fungal trait data collected at community level in Spring and Fall 2022 from Lecompton, KS

• plot: field ID for plot
• treatment: fire regime treatment (no burn = no fire, annual = annual fire, biennial = biennial fire, triennial = triennial fire)
• time: sampling time, fall22=October 2022, spr22=April 2022
• fire: occurence of fire during 2022 (yes = fire, no = no fire)
• season: indicates season of fire (fall = Fall fire, spring = Spring fire)
• column: pertains to field plot location (East/West orientation)
• row: pertains to field plot location (North/South orientation)
• intensity: average spore color intensity (0 = black, 255= pure color)
• hue: average spore color on 0-360 degree color wheel
• saturation: average spore color saturation (0 = white, 255 = pure color)
• radius: average spore radius in uM
• luminance: average spore color luminance, denotes how "bright" a color appears (0 = black, 255 = white)
• volume: average spore volume based on (4/3)*pi*r^3
• density: spore counts per 100 mL of soil
• richness: spore species/morphotypes observed per 100 mL of soil

traits_species-level.csv:

AM fungal trait data collected at species level in Spring and Fall 2022 from Lecompton, KS

• plot: field ID for plot
• treatment: fire regime treatment (no burn = no fire, annual = annual fire, biennial = biennial fire, triennial = triennial fire)
• fire: occurence of fire during 2022 (yes = fire, no = no fire)
• season: indicates season of fire (fall = Fall fire, spring = Spring fire)
• column: pertains to field plot location (East/West orientation)
• row: pertains to field plot location (North/South orientation)
• species: denotes which species/morphotype a spore belongs to (values correspond with spore_communities.csv columns H through Y)
• sampletime: sampling time, fall22=October 2022, spr22=April 2022
• intensity: spore color intensity (0 = black, 255= pure color)
• hue: spore color on 0-360 degree color wheel
• saturation: spore color saturation (0 = white, 255 = pure color)
• luminance: spore color luminance, denotes how "bright" a color appears (0 = black, 255 = white)
• radius: spore radius in uM
• volume: spore volume based on (4/3)*pi*r^3