Wald test (Plantae)

Knowledge graph centered on Wald test (Plantae) with 21 nodes and 70 connections. Top connected: Plot-scale evidence of tundra vegetation change an, Salix lucida subsp. lasiandra, vascular plants, Vaccinium, Ranunculus.

Method synopsis

Wald tests were used to correlate temporal changes in tundra vegetation response groups with summer temperature changes and environmental interaction terms. Multiple testing corrections were applied to control for false discovery rates.

Synthesized from method descriptions across 1 paper using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Plot-scale evidence of tundra vegetation change and links to recent summer warming (2012), Nature Climate Change. Implementations in other papers (listed below) may differ.

1. Establish study inclusion criteria
   Permanently located quadrats or study areas which were sampled using the same methodology at least twice between 1980 and 2010 with a minimum of 5 years between the first and last sampling years. Studies in areas undergoing obvious recovery from recent disturbance and plots with standing water were omitted since it was difficult to sample submerged vegetation accurately.
   Quantities: 158 studies across 46 locations, spanning 1980-2010 with minimum 5 years between samplingsDuration: Studies ranged from 5-27 years duration, median 11 yearsConditions: Excluded areas with recent disturbance or standing water
   Equipment: Various sampling methods per original studies
2. Quantify plant abundance using multiple methods
   Plant abundance was quantified as: biomass (8 studies), point frame hits (total- 68 studies; top and bottom only- 15 studies; or top only- 14 studies), visual cover estimates (48 studies), subplot frequency (1 study), or stem counts (4 studies). Morphologically similar groups of taxa that were not consistently separated across all years of a given study were grouped to morphospecies.
   Quantities: 68 studies used point frame hits, 48 used visual cover estimates, 8 used biomass, 15 used top and bottom point frame hits only, 14 used top only, 1 used subplot frequency, 4 used stem countsDuration: Median number of samplings per study was 3 (range 2-28)Conditions: Consistent methodology within each study across all years
   Equipment: Point frames, visual estimation methods, biomass collection tools, stem counting methods

Typical Equipment

• statistical software

Output Measurements

• p-values
• correlation significance

Papers Using This Protocol (1)

Species Studied With This Protocol

Places Where Used