Nina Wurzburger
Odum School of Ecology
University of Georgia
Athens, GA 30602-2202 USA
E-mail: [email protected]

S. Joseph Wright
Smithsonian Tropical Research Institute
Apartado 0843-03092
Balboa, Republic of Panama
E-mail: [email protected]

fertilization_treatments.csv (MD5: 89bc45540bf3305cb2ef152cc68eaa0f)

root_abundance_and_morphological_traits.csv (MD5: 31d7fb5a0a3858148df72683d227b914)

root_nutrients.csv (MD5: 168940dbbfac94021d6be522d4978e9a)

mycorrhizal_colonization.csv (MD5: f83d44888e6ffd45b60544ae605873f1)

fertilization_treatments.csv is a comma-separated text file containing the fertilization treatments of the Gigante experiment. Column definitions are:

1. treatment is the fertilization treatment, where N = nitrogen, P = phosphorus and K = potassium.
2. plot is the plot number associated with each treatment.

root_abundance_and_morphological_traits.csv is a comma-separated text file containing the root abundance and morphological trait dataset. Column definitions are:

1. plot is treatment plot.
2. core is core sample number.
3. size_class is root diameter size class, where 0 = 0–1 mm, 1 = 1–2 mm and 2 = 0–2 mm.
4. biomass is root biomass in g/m2
5. length is root length in m/m2
6. t_den is root tissue density in g/cm3
7. srl is specific root length in cm/g
8. avg_diam is average root diameter in mm.

root_nutrients.csv is a comma-separated text file containing the nutrient content of root tissue samples. Column definitions are:

1. plot is treatment plot
2. size_class is root diameter size class, where 0 = 0–1 mm, 1 = 1–2 mm and 2 = 0–2 mm.
3. N is root tissue nitrogen concentration (%).
4. C is root tissue carbon concentration (%).
5. P is root tissue phosphorus concentration (ppm).
6. K is root tissue potassium concentration (ppm).

mycorrhizal_colonization.csv is a comma-separated text file containing mycorrhizal colonization dataset. Column definitions are:

1. plot is treatment plot.
2. arb_per is colonization of arbuscules expressed as a percent of root length
3. ves_per is colonization of vesicles expressed as a percent of root length
4. hyp_per is colonization of hyphae expressed as a percent of root length
5. tot_per is total colonization expressed as a percent of root length
6. arb_len is colonization of arbuscules expressed as root length (cm).
7. ves_len is colonization of vesicles expressed as root length (cm).
8. hyp_len is colonization of hyphae expressed as root length (cm).
9. tot_len is total colonization expressed as root length (cm).