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Keen of Hamar Nutrient Addition trials

Sarah E. Dalrymple*, John Hopkins, Stephen Carter** & David S. Slingsby***

*s.e.dalrymple@ljmu.ac.uk, Liverpool John Moores University,Liverpool, United Kingdom.
**Headland Archaeology, Edinburgh, Scotland.
***The Open University, United Kingdom

Published April 2025

Description

Nutrient addition experiments initiated in 1980 on the Keen of Hamar, Shetland Isles, have produced a unique dataset of long-term vegetation response to amendments of major plant growth nutrients (N, P, NP, NPK and NPKCa).
This dataset presents the results from surveys in 1981, 1984, 1992, 1993, 2006, 2010 and 2013 using 1 m x 1 m quadrats with pin frame (pins spaced 10 cm apart).
Quadrats are placed in serpentine communities corresponding to sparse and moderate vegetation cover.
Quadrat numbers correspond to clusters of treatments/control with the following Ordnance Survey grid references:

Sparsely-vegetated debris, quadrats 29/30: HP6442109996
Moderately-vegetated debris, quadrats 23/24:HP6415409910

Full methods are available here:
Dalrymple, S. E., Hopkins, J., Carter, S. P., & Slingsby, D. R. (2019). Nutrient additions three decades on: potential interactions of nutrients and climate in the recovery of a high latitude serpentine system. Plant Biosystems - An International Journal Dealing with All Aspects of Plant Biology, 155(1), 64–72. https://doi.org/10.1080/11263504.2019.1701578

Terms of use 

CC-BY: This Creative Commons license lets others distribute, remix, tweak, and build upon this work, with attribution to the authors.


Contents

Data: KeenOfHamar_NutrientAdditionTrials_data.xlsx
Column headers: 
	Plot code - unique code identifying quadrat number, treatment and year of survey
	Quadrat - one of 23, 24, 29 or 30 - see above for location and vegetation cover
	Debris state - one of 'Sparse' or 'Moderate' referring to level of vegetation cover
	Treatment - one of Control, N, P, NP, NPK, NPKCa, see Dalrymple et al 2019 for details
	Year - year of survey, one of 1981, 1984, 1992, 1993, 2006, 2010 or 2013
	All remaining column headers refer to species - see below

KeenOfHamar_NutrientAdditionTrials_speciesList.xlsx
Provides species codes with full species name and notes on likely taxonomic ambiguity, subspecies and synonyms