McMurdo Dry Valleys LTER
Published on McMurdo Dry Valleys LTER (https://mcm.lternet.edu)


Summary

Abstract: 

Soil communities in the McMurdo Dry Valleys are subject to many limitations, including resource limitations. However, the nutrients that are predominantly limiting to growth and diversity of soil biota are not known. Additionally, landscape history (N deposition, P weathering) and native N and P content (glacial till provenance) may influence the ability of soil communities to respond to nutrient additions or changes in nutrient availability associated with environmental change. Long-term experiments in the Bonney and Fryxell basins have been established with yearly application of aqueous nutrient additions: C, N, P, CN, and CP. Multiple nutrients additions were made at the Redfield Ratio of 106:16:1 (C:N:P). Responses of soil chemistry, CO2 flux, and biota are reported.

Date Range: 

January 26, 2003 to January 16, 2010
Dataset(s)

Description: 

Details about the spreadsheet containing the SE data - units, columns, definitions, missing values and codes and the such

Variables (click to expand): 

DATASET_CODE
  • Label:
  • Definition: Unique identifier for the table in the MCM LTER database
  • Type: Nominal
  • Missing values: None specified
BASIN
  • Label:
  • Definition: The lake basin where the soil sample was collected from (Bonney or Fryxell).
  • Type: Code list
  • Codes:
    • Bonney = Lake Bonney Basin
    • Fryxell = Lake Fryxell Basin
  • Missing values: None specified
SAMPLE_ID
  • Label:
  • Definition: The block and treatment combination of the sample. (C) carbon additions as mannitol (N) nitrogen additions as NH4NO3 (P) phosphorus additions as Na3PO4 (CN) carbon and nitrogen additions (CP) carbon and phosphorus additions, (W) water-only additions (U) un-amended plots. The numbers indicated the plot/block number
  • Type: Nominal
  • Missing values: None specified
BLOCK_ID
  • Label:
  • Definition: The block number that the soil sample was collected from.
  • Type: Nominal
  • Missing values: None specified
TREATMENT
  • Label:
  • Definition: The manipulation for a given plot from where the soil was collected.
  • Type: Code list
  • Codes:
    • C = carbon additions as mannitol
    • N = nitrogen additions as NH4NO3
    • P = phosphorus additions as Na3PO4
    • CN = carbon and nitrogen additions
    • CP = carbon and phosphorus additions,
    • W = water-only additions
    • U = un-amended plots.
  • Missing values: None specified
PRE_DATE_TIME
  • Label:
  • Definition: The date and time CO2 flux was measured in the field before re-application of treatment
  • Type: Date/time
  • Date format: MM/DD/YYYY HH24:MI
  • Missing values: None specified
PRE_CO2
  • Label:
  • Definition: Soil CO2 flux measured using LI-8100 before re-application of treatment
  • Type: Physical quantity
  • Unit: micromol CO2/m2sec
  • Maximum: Not specified
  • Minimum: 0
  • Precision: Not specified
  • Missing values:
    • Null = None given
PRE_TEMP
  • Label:
  • Definition: Soil temperature at time of CO2 flux measurement before re-application of treatment
  • Type: Physical quantity
  • Unit: celsius
  • Maximum: Not specified
  • Minimum: 0
  • Precision: Not specified
  • Missing values:
    • Null = None given
PRE_MOISTURE
  • Label:
  • Definition: Soil moisture at time of CO2 flux measurement before re-application of treatment
  • Type: Physical quantity
  • Unit: g/g soil
  • Maximum: 100
  • Minimum: 0
  • Precision: Not specified
  • Missing values:
    • Null = None given
POST_DATE_TIME
  • Label:
  • Definition: The date and time CO2 flux was measured in the field after re-application of treatment
  • Type: Date/time
  • Date format: MM/DD/YYYY HH24:MI
  • Missing values: None specified
POST_CO2
  • Label:
  • Definition: Soil CO2 flux measured using LI-8100 before re-application of treatment
  • Type: Physical quantity
  • Unit: micromol CO2/m2sec
  • Maximum: Not specified
  • Minimum: 0
  • Precision: Not specified
  • Missing values:
    • Null = None given
POST_TEMP
  • Label:
  • Definition: Soil temperature at time of CO2 flux measurement after re-application of treatment
  • Type: Physical quantity
  • Unit: celsius
  • Maximum: Not specified
  • Minimum: 0
  • Precision: Not specified
  • Missing values:
    • Null = None given
POST_MOISTURE
  • Label:
  • Definition: Soil moisture at time of CO2 flux measurement after re-application of treatment
  • Type: Physical quantity
  • Unit: g/g soil
  • Maximum: 100
  • Minimum: 0
  • Precision: Not specified
  • Missing values:
    • Null = None given
COMMENTS
  • Label:
  • Definition: Generic comments about the sample
  • Type: Nominal
  • Missing values: None specified
DATE_TIME
  • Label:
  • Definition: The date and time of the second measurement, same as POST_DATE_TIME
  • Type: Date/time
  • Date format: MM/DD/YYYY HH24:MI
  • Missing values: None specified

File: 

SOILS_SE_CO2.csv (26.82 KB)

Short name: 

SE_CO2

Dataset ID: 

4014
People

Principal Investigator(s): 

Ross A. Virginia
Diana H. Wall

Contact: 

McMurdo Dry Valleys LTER

Associated Personnel: 

Field Crew
Becky A. Ball
Data Manager
Sue Welch
Data Manager
Inigo San Gil
Methodology

Methods: 

Three sites were chosen on generally flat areas of moderately patterned soil. Plots were laid out in an identical design at each site. There are 7 treatments replicated 8 times in blocks. Treatments were randomly assigned to the plots within each block. Each plot measures 1 m x 1 m (with a 0.83 m diameter area within used for experimental treatments and analyses). Plots are delineated by nails inserted in the soil, and the margins of each site are marked by PVC stakes approximately 60 cm high.

Water and aqueous nutrient treatments were applied annually at a rate of 5.6 L per plot, with 15 g C m-2 as mannitol, 2.5 g N m-2 as NH4NO3, and/or 0.75 g P m-2 as Na3PO4 (see Treatment Codes under Additional Information). Each plot was fitted with a 10-cm diameter PVC collar that created a seal with the soil. Soil CO2 flux from each PVC collar was measured using a LI-COR 8100 (Lincoln, NE), fitted with a soil respiration survey chamber. At each measurement, soil temperature in the surrounding soil was measured using soil temperature probe Type E. Soil moisture of the surrounding soil was measured using a Theta probe Model ML2. Measurements of CO2 flux, temperature, and moisture were taken within 2 weeks prior to annual treatment application, then again approx. 2 weeks after annual treatment application.

Maintenance: 

Jan, 2010 - Sue Welch created this metadata and accompanying Oracle data table from metadata info and an Excel spreadsheet from Becky Ball .

Additional information: 

In the attribute table, the treatment is the manipulation for a given plot from which the soil was collected. The treatments are: (C) carbon additions as mannitol, (N) nitrogen additions as NH4NO3, (P) phosphorus additions as Na3PO4, (CN) carbon and nitrogen additions, (CP) carbon and phosphorus additions, (W) water-only additions, and (U) un-amended plots.
Categories

Research Section: 

  • Soils
  • Soil Chemistry

LTER Core Areas: 

  • population dynamics

MCM Keywords: 

  • Antarctica
  • carbon
  • CO2
  • LTER
  • nematodes
  • soil
  • soil moisture
  • soil temperature
  • Stoichiometry

Keywords: 

  • carbon dioxide
  • soil moisture
  • soil temperature
  • soil water content

Source URL: https://mcm.lternet.edu/content/stoichiometry-experiment-co2