Details and Metadata

Printer-friendly version     View XML version    Download Ecological Metadata Language file


Methods

The methods followed in the creation of the dataset, including description of field, laboratory and processing steps, and quality control procedures

Current Methods

  • Study specimens
    Started: 1993-05-01

    Twenty sugar maple trees used for foliage sampling.

  • Plot description

    One 75 X 50 m plot used for soil, litter, throughfall and precipitation collections.

  • Leaf samples

    Leaf samples collected from north and south sides of tree; from lower, middle and upper canopy. Samples of leaves were collected once in mid-July and once in mid-August to obtain a measure of the maximum nitrogen pool. Foliar nutrient concentrations are most stable in this time frame.

  • Leaf litter
    Started: 1993-09-20

    Leaf litter traps collected twice weekly. One litter trap was placed under each tree, positioned so that minimal litter would fall in from surrounding trees. Leaf litter was collected throughout the leaf drop period (September 20-October 22).

  • Throughfall collection

    Throughfall collections consisted of two funnel collectors under each of five trees, on north and south sides of tree. Plus two collectors in an open area in close proximity to the site to collect rain as a control.

  • Leaf tissue analysis

    After each sampling, leaf tissue was run through a leaf area meter, assigned a thrips damage index number, oven dried at 70 degrees C to a constant weight and ground in a Wiley mill.

Dataset Fields

Detailed documentation of the fields comprising the dataset, including the type of measurement, units where applicable, and any controlled vocabularies or code lists present in the data


Field Name Caption Description Additional Information
Tree_numberTree #

Number of the tree sampled

Measurement type: Ordinal
GreenFoliarN_ug_cm2Green Foliar N

Nitrogen from live leaf samples

Measurement type: Ratio
Unit: unavailable
Precision: 0.01
GreenFoliarN_ug_cm2_SEGreen Foliar N Southeast

Nitrogen from live leaf samples in the Southeast

Measurement type: Ratio
Unit: unavailable
Precision: 0.01
GreenFoliarN_pctdrywtGreen Foliar N Weight

Nitrogen from live leaf sample measured by the percent of dry weight

Measurement type: Ratio
Unit: unavailable
Precision: 0.01
GreenFoliarN_pctdrywt_SEGreen Foliar N Weight

Nitrogen from live leaf sample measured by the percent of dry weight (southeast)

Measurement type: Ratio
Unit: unavailable
Precision: 0.01
LitterN_ug_cm2Leaf litter N

Nitrogen from leaf litter samples

Measurement type: Ratio
Unit: unavailable
Precision: 0.01
LitterN_ug_cm2_SELeaf litter N SE

Nitrogen from leaf litter samples (southeast)

Measurement type: Ratio
Unit: unavailable
Precision: 0.01
Resorption_pctPercent Resorption

Percent nitrogen resorbed is calculated as 100* (maximum N mass/leaf area)-(leaf litter N mass/ leaf area)

Measurement type: Ratio
Unit: unavailable
Precision: 0.01
Resorption_pct_SEPercent Resorption SE

Percent nitrogen resorbed is calculated as 100* (maximum N mass/leaf area)-(leaf litter N mass/ leaf area) (southeast)

Measurement type: Ratio
Unit: unavailable
Precision: 0.01

Sampling Equipment

Equipment and software used to collect data, including how that equipment was used.

Current Equipment

  • Chromatograph

    Dionex Ion Chromatograph Model 2010i was used to analyze nitrate.

  • Flow injection analysis

    Lachat Quick Chem AE flow injection analysis was used to test ammonium colorimetrically.

  • Elemental Analyzer
    Started: 1993-05-01

    Leeman Laboratories CHN CE440 Elemental Analyzer was used to determine total nitrogen.

  • Leaf litter traps, funnel precipitation colle
    Started: 1993-05-01

    Leaf litter traps. Funnel precipitation collectors.

  • Pole pruners, ladders and rope climbing equip
    Started: 1993-05-01

    Pole pruners, ladders and rope climbing equipment.

Site Characteristics

The spatial extent of the dataset site coverage, and descriptions of the spatial extent and context for the data collection

  • Site Description

    Stevensville Brook watershed, west slope of Mt. Mansfield, northern hardwood forest.

  • Site Description

    The site is in the drainage of Nettle Brook, a small tributary to the north branch of Stevensville Brook.