Field experiment testing effect of increased water and nutrient availability on Windmill Islands terrestrial vegetation communities

Brief description

Description of the work is provided in the file named: ASAC 1087_WN-descriptions.doc

The work consists of a multiseason manipulative field experiment investigating the effect of increased water and nutrient availability on Antarctic terrestrial communities. For full details refer to Chapter 4 in Wasley (2004).

The experiment was conducted in Antarctic Specially Protected Area (ASPA) 135, on Bailey Peninsula, approximately 1 km east of Casey Station. The site was located on the western edge of a meltlake, at 66 degrees 16.03' S, 110 degrees 32.53' E.

Within the site, four community types, along a community gradient, were identified based on the percentage cover of four key community components: healthy bryophytes, moribund bryophytes, crustose lichens and macrolichens of the genus Usnea (herein referred to as: Bryophyte, Moribund, Crustose and Usnea, respectively). The four communities occurred along a gentle slope, with an easterly aspect, between the meltlake edge and the side of a small ridge. The Bryophyte community occurred closest to the meltlake, and the other three communities were positioned with increasing distance from the meltlake edge, in the order of: Moribund community, Crustose community and, furthest from the meltlake, the Usnea community, which was closest to the ridge.

Within each community, 32 quadrats (25 x 25 cm) were randomly assigned one of the following four treatments: (1) no-treatment (NT-), (2) water only (W-), (3) nutrient only (N-), or (4) water and nutrient (WN-). The two water addition treatments (W- and WN-) had 500 ml of meltlake water applied approximately every two days during the 1998/99 and 1999/00 summer seasons (December - February). Quadrats receiving nutrient additions (N- and WN-) had 10 g of slow release fertiliser beads (Osmocote, Scotts Australia Pty. Ltd., Castle Hill, NSW, Australia) applied at the start of the treatment period (15/12/99). A low phosphorous Osmocote variety was used, composed of 18% nitrogen, 4.8% phosphorous and 9.1% potassium.

The effect of increased water and nutrient availability was assessed via a suite of ecological, physiological and biochemical endpoints (as described in ASAC 1087_WN-descriptions.doc), including plant pigment and nutrient contents, field photosynthetic rates, composition of soluble sugars and species/community compositions.

Information regarding sample ID:
This experiment used a three letter code to denote Sample ID. Letters correspond with colours that were used for markers placed at quadrat locations in the field. The markers were made of three coloured plastic beads on a wire peg. The letters in the sample ID code correspond with the three colours used to mark the quadrat (e.g. GPR = Green, Purple, Red), using the following key:

1. First bead / first letter: indicated REPLICATES, where:
Rep1 = B (Blue)
Rep 2 = P (Purple)
Rep 3 = R (Red)
Rep 4 = O (Orange)
Rep 5 = Y (Yellow)
Rep 6 = L (Lime)
Rep 7 = G (Green)
Rep 8 = W (White)

2. Second bead / second letter: indicates TREATMENT, where:
Control = W (White)
Water = B (Blue)
Nutrient = L (Lime)
Water and Nutirent = P (Purple)

3. Third bead / third letter: indicates COMMUNITY, where:
Bryophyte = G (Green)
Moribud = O (Orange)
Crustose = Y (Yellow)
Usnea = R (Red)


Note for data file: ASAC 1087_WN-NPC.xls
This file provides treatment and community level codes, but is missing replicate ID.
To source replicate ID, match up Column A: No. (97 to 208) with that provided in the laboratory notebook scan at: https://data.aad.gov.au/metadata/records/JWasley-LabBook-Casey-1999-2000; pages 188 to 194).

Sample ID (three letter) codes are listed:
From: Page 188, line marked #97 = LPR = Lime, Purple, Red = Rep6, W&N Treatment, Usnea Community
To: Page 194, line marked #208 = OWG = Orange, White, Green = Rep4, Control Treatment, Bryophyte Community
Use sample ID code information above in description to identify other Sample ID codes in this file.