Gains in soil C storage under anthropogenic N deposition are rapidly lost following its cessation
Data files
Sep 06, 2024 version files 18.40 KB
-
enzymes.csv
3.57 KB
-
mineral_soil_C.csv
1.34 KB
-
organic_horizon_C.csv
4.08 KB
-
organic_horizon_mass.csv
430 B
-
organic_horizon_N.csv
3.52 KB
-
README.md
3.74 KB
-
respiration.csv
1.72 KB
Abstract
In the northern Hemisphere, anthropogenic nitrogen (N) deposition contributed to the enhancement of the global terrestrial carbon (C) sink, partially offsetting CO2 emissions. Across several long-term field experiments, this ecosystem level response was determined to be driven, in part, by the suppression of microbial activity associated with the breakdown of soil organic matter. However, since the implementation of emission abatement policies in the 1970’s, atmospheric N deposition has declined globally, and the consequences of this decline are unknown. Here, we assessed the response of soil C storage, and associated microbial activities, in a long-term field study that experimentally increased N deposition for 24-years. We measured soil C and N, microbial activity, and compared effect sizes of soil C in response to, and in recovery from, the N deposition treatment across the history of our experiment (1994-2022). Our results demonstrate that the accumulated C in the organic horizon has been lost and exhibit additional deficits 5-years post-termination of the N deposition treatment. These findings, in part, arise from mechanistic changes in microbial activity. Soil C in the mineral soil was less responsive thus far in recovery. If these organic horizon C dynamics are similar in other temperate forests, the northern Hemisphere C sink will be reduced and climate warming will be enhanced.
README: README: Gains in soil carbon storage under anthropogenic nitrogen deposition are rapidly lost following its cessation
Corresponding author: Zachary B. Freedman
E-mail: zfreedman@wisc.edu
The raw data submitted include the following parameters: organic horizon carbon content, organic horizon nitrogen content, mineral soil carbon content, organic horizon mass, soil respiration, and soil extracellular enzyme activity potential.
Description of the data and file structure
All data files contain the following information:
-"Site": site where sample was collected from. There are 4 sites in Michigan, USA that are located:
-"A": 46°52'N, 88°53'W
-"B": 45°33'N, 84°51'W
-"C": 44°23'N, 85°50'W
-"D": 43°40'N, 86°09'W
-"Plot": numeric identifier given to each 30 x 30 meter plot (n = 6 per site)
-"Treatment": refers to the amount of nitrogen deposition at the plot-level
-"Ambient": plots that receive ambient atmospheric nitrogen deposition (wet + dry total deposition), which varies by site
-Site A: 0.68 g N m-2 y-1
-Site B: 0.91 g N m-2 y-1
-Site C: 1.17 g N m-2 y-1
-Site D: 1.18 g N m-2 y-1
-"NDep": plots that received experimental nitrogen additions in the form of 30kg NO3--N ha-1 yr-1 from 1994-2017
-"Type": refers to soil type
-"Organic horizon": Oe/Oa horizon
-"Mineral soil": 0-10cm depth, A horizon of sandy spodosol soil (Kalkaska series)
- Organic horizon carbon content (organic_horizon_C.csv) -Organic horizon carbon content of one homogenized sample per plot per site (from 10 random 10 by 10 cm cut squares of Oe/Oa horizon) for each sampling year -For years 1994-2016, values are expressed in g kg-1 -For the year 2022, values are expressed twice. Under the "2022 (g/m2)" column the values are expressed in g/m2. Under the "2022 (%)" column, the values are expressed as % -Both forms are used/presented in the manuscript and hence why the data is presented twice in the raw data file
- Organic horizon nitrogen content (organic_horizon_N.csv) -Organic horizon nitrogen content of one homogenized sample per plot per site (from 10 random soil cores to 10 cm depth) for each sampling year -For years 1994-2016, values are expressed in g kg-1 -For the year 2022, values are expressed twice. Under the "2022 (g/m2)" column the values are expressed in g/m2. Under the "2022 (%)" column, the values are expressed as % -Both forms are used/presented in the manuscript and hence why the data is presented twice in the raw data file
- Mineral soil carbon content (mineral_soil_C.csv) -Mineral soil carbon content of one homogenized sample per plot per site (from 10 random soil cores to 10 cm depth) for each sampling year -Values are expressed in g/m2
- Organic horizon mass (organic_horizon_mass.csv) -Mass of the homogenized organic horizon sample per plot per site (from 10 random 10 by 10 cm cut squares of Oe/Oa horizon) collected between 14-17 September 2022 -Values are expressed in g/m2
- Respiration (respiration.csv) -Soil respiration of one homogenized sample per plot per site collected between 14-17 September 2022 -Respiration values were obtained by performing a laboratory incubation experiment -Respiration measurements were taken 24, 48, and 72 hours after jar wetting using an EGM-5 Infrared Gas Analyzer (IRGA) -Values obtained from the 72-hour sampling period were used to calculate C respired as g C g soil-1 s-1
- Enzymes (enzymes.csv) -Soil extracellular enzyme activity potential of one homogenized sample per plot per site collected between 14-17 September 2022 -"Moisture": % moisture of sample (determined in lab) -"PER": Peroxidase -"PPO": Polyphenol Oxidase -"BG": Beta-Glucosidase