Soil functions (potential enzyme activity and nitrogen cycling rates) from manipulative experiment adding fertilizer and supplemental late-spring precipitation to a 50-ha northern California grassland underlain by a mosaic of serpentine and non-serpentine soils (November 2012-May 2013)

Experiment added fertilizer and supplemental late-spring precipitation to a 50-ha northern California grassland underlain by a mosaic of serpentine and non-serpentine soils. Measurements of soil functions were taken after three years of consistent treatment application. Contents are as follows: "plot.name": unique name for each of the 132 plots in the experiment "irrigation.line": code indicating which irrigation line carried the supplemental precipitation to the plot "soil.type": whether the plot was on harsh serpentine (Harshserp), lush serpentine (Lushserp), or non-serpentine (Nonserp) soil "treatment": C = control (no fertilizer or water added), F = fertilized (fertilizer added but no water added), W = watered (water added but no fertilizer added), FW = fertilized + watered (both fertilizer and water added) "watering": whether the plot was watered or unwatered "fertilization": whether the plot was fertilized or unfertilized "tpc.native": total proteolytic capacity with native substrate (no substrate added to soil) [mg N-AA / kg dry soil / day]; measured early May 2013 "tpc.saturated": total proteolytic capacity with saturated substrate (saturating amount of casein added to soil) [mg N-AA / kg dry soil / day]; measured early May 2013 "BG": potential activity of beta-1,4-glucosidase [mmol substrate cleaved / kg dry soil / hour]; measured early May 2013 "NAG": potential activity of beta-N-acetylglucosaminidase [mmol substrate cleaved / kg dry soil / hour]; measured early May 2013 "AP": potential activity of acid phosphatase [mmol substrate cleaved / kg dry soil / hour]; measured early May 2013 "PPO": potential activity of polyphenol oxidase [mmol substrate cleaved / kg dry soil / hour]; measured early May 2013 "PER": potential activity of peroxidase [mmol substrate cleaved / kg dry soil / hour]; measured early May 2013 "fall.net.mineralization.rate": rate of net nitrogen mineralization during 7-day laboratory incubation at field moisture content [mg NH4-N + NO3-N / kg dry soil / day]; measured on soil samples collected early November 2012 "fall.net.nitrification.rate": rate of net nitrification during 7-day laboratory incubation at field moisture content [mg NO3-N / kg dry soil / day]; measured on soil samples collected early November 2012 "winter.net.mineralization.rate": rate of net nitrogen mineralization during 7-day laboratory incubation at field moisture content [mg NH4-N + NO3-N / kg dry soil / day]; measured on soil samples collected early February 2013 "winter.net.nitrification.rate": rate of net nitrification during 7-day laboratory incubation at field moisture content [mg NO3-N / kg dry soil / day]; measured on soil samples collected early February 2013 "earlyspring.net.mineralization.rate": rate of net nitrogen mineralization during 7-day laboratory incubation at field moisture content [mg NH4-N + NO3-N / kg dry soil / day]; measured on soil samples collected mid-March 2013 "earlyspring.net.nitrification.rate": rate of net nitrification during 7-day laboratory incubation at field moisture content [mg NO3-N / kg dry soil / day]; measured on soil samples collected mid-March 2013 "latespring.net.mineralization.rate": rate of net nitrogen mineralization during 7-day laboratory incubation at field moisture content [mg NH4-N + NO3-N / kg dry soil / day]; measured on soil samples collected late May 2013 "latespring.net.nitrification.rate": rate of net nitrification during 7-day laboratory incubation at field moisture content [mg NO3-N / kg dry soil / day]; measured on soil samples collected late May 2013