DOI: 10.5061/dryad.1ns1rn90w
title: Data from: Climatic effects on the synchrony and stability of temperate headwater invertebrates over four decades

description: Important clues about the ecological effects of climate change can arise
 from understanding the influence of other Earth-system processes on
 ecosystem dynamics but few studies span the inter-decadal timescales
 required. We, therefore, examined how variation in annual weather patterns
 associated with the North Atlantic Oscillation (NAO) over four decades was
 linked to synchrony and stability in a metacommunity of stream
 invertebrates across multiple, contrasting headwaters in central Wales
 (UK). Prolonged warmer and wetter conditions during positive NAO winters
 appeared to synchronise variations in population and community composition
 among and within streams thereby reducing stability across levels of
 ecological organisation. This climatically-mediated synchronisation
 occurred in all streams irrespective of acid-base status and land use, but
 was weaker where invertebrate communities were more functionally diverse.
 Wavelet linear models indicated that variation in the NAO explained up to
 50% of overall synchrony in species abundances at a timescale of 4-6
 years. The NAO appeared to affect ecological dynamics through
 local variations in temperature, precipitation and discharge, but
 increasing hydrochemical variability across sites during wetter winters
 might have contributed.  Our findings illustrate how large-scale
 climatic fluctuations generated over the North Atlantic can affect
 population persistence and dynamics in inland freshwater ecosystems in
 ways that transcend local catchment character. Protecting and restoring
 functional diversity in stream communities might increase their stability
 against warmer, wetter conditions that are analogues of ongoing climate
 change. Catchment management could also dampen impacts and provide options
 for climate change adaptation.
description: ## Climatic effects on the synchrony and stability of temperate headwater
 invertebrates over four decades ### GENERAL INFORMATION 1. Title: Climatic
 effects on the synchrony and stability of temperate headwater
 invertebrates over four decades 2. Authors A) Corresponding author:
 Stefano Larsen; Research and Innovation Centre, Fondazione Edmund Mach,
 Italy B) Senior author: Steve Ormerod; Water Research Institute, Cardiff
 School of Biosciences, Cardiff University, Cardiff, UK. 3. Geographic
 location of the study. Llyn Brianne Catchment, Central Wales, UK. 4.
 Timescale of data: 1985-2018 5. Type of data: -Stream invertebrate
 abundance, collected with standard methods from the Freshwater Biological
 Society. -Elaborated climatic and hydro-chemical data derived from Natural
 Resources Wales. ### SHARING/ACCESS INFORMATION 1. Licenses/restrictions
 placed on the data: CC0 1.0 Universal (CC0 1.0) Public Domain 2. Links to
 publications that cite or use the data: Stefano Larsen; Fiona Joyce; Ian
 P. Vaughan; Isabelle Durance; Jonathan Walter; Steve J. Ormerod. (2023).
 Climatic effects on the synchrony and stability of temperate headwater
 invertebrates over four decades. Global Change Biology. ### DATA
 INFORMATION Data tables in .csv format are included. Dataset named
 'bugs.long.imp.csv' reports the biological data and include
 three columns: * CODE: Name code of the stream * Year: year of collection
 * Species: Taxonomic name of the species, or Genus, or Family. * abund:
 number of collected individuals. Dataset named
 'LB_chem.season.imputed.csv' reports mean values of the
 hydro-chemical data and includes multiple columns: * winter.year: the year
 of collection associated with the spring sampling of macroinvertebrates *
 Season: the season (summer, winter) * Site: name code of the stream
 (corresponding to CODE in the biological dataset) * pH: pH * Cond20C:
 water conductivity (uS/cm) * N_Oxidised: Nitrogen concentration in
 oxidised form, as NOx (mg/l) * Hardness: water hardness (mg/l) *
 Alky_pH_4.5: alkalinity at pH of 4.5 (mg/l) * Chloride_ion: concentration
 of Chloride ions (mg/l) * Na_Filtered: Sodium concentration (mg/l) *
 K_Filtered: Potassium concentration (mg/l) * Mg_Filtered: Magnesium
 concentration (mg/l) * Ca_Filtered: Calcium concentration (mg/l) *
 Al_Filtered: Aluminium concentration (ug/l) * Mn_Filtered: Manganese
 concentration (ug/l) * Fe_Filtered: Iron concentration (ug/l) Dataset
 named 'LB10_temperature.csv' reports air temperature (Celsius)
 values for winter, and include three columns: * Winter.year: the year
 associated with the spring sampling of macroinvertebrates * Site: name
 code of the stream (corresponding to CODE in the biological dataset) *
 mean.w.T: the mean air temperature for the given year Dataset named
 'LB10_precipitation_w.csv' reports precipitation values for
 winter, and include the following columns: * winter.year: the year of
 collection associated with the spring sampling of macroinvertebrates *
 m.mean: mean daily precipitation (mm) for the winter months