DOI: 10.5061/dryad.cz8w9gjgm
title: Data from: The ameliorating influence of neighbouring plants on aboveground microclimate depends on their number, size, and proximity

description: Plants can have a facilitative effect on co-occurring neighbours by
 moderating microclimate conditions. In forested areas, vegetation can
 ameliorate macroclimate extremes relative to open areas, yet the
 neighbourhood characteristics that contribute to this buffering effect,
 particularly during early stand development, remain unclear. Here, we
 examined how the local neighbourhood affects aboveground temperature and
 relative humidity in the canopy layer of 76 mapped neighbourhood plots in
 an 8-year-old experimental forest in Tasmania, Australia. We assessed
 which aspects of the neighbourhood – species identity, density, summed
 basal area and spatial arrangement – best described the microclimatic
 conditions over a year-long period, and examined how seasonal and extreme
 climatic conditions influenced the strength of neighbourhood effects on
 microclimate. Microclimate conditions varied substantially across
 neighbourhoods, with a significant proportion explained by neighbourhood
 metrics (NMs). Daytime temperature and relative humidity (RH) were
 strongly associated with the community neighbourhood index (NI), which
 reflects the number, size and proximity of neighbouring trees rather than
 their species identity. Higher NI values – indicating more, larger or
 closer neighbours – led to cooler, moister microclimates, with the
 strongest effects observed in summer, where NI explained 57 % of the
 variation in temperature and 33% in RH. Although nighttime microclimate
 relationships with NMs were generally weaker, they were positively
 associated with the number and size of neighbours (summed basal area). The
 buffering effect of high NI and basal area neighbourhoods was most evident
 under extreme climatic conditions, with temperatures 3.5 °C cooler on the
 hottest recorded day and 1.2 °C warmer during the coldest. The
 amelioration in microclimatic conditions due to neighbouring plants has
 important implications for tree performance and forest regeneration,
 particularly in projected hotter and drier conditions.
description: # Dryad dataset Dataset DOI:
 [10.5061/dryad.cz8w9gjgm](10.5061/dryad.cz8w9gjgm) ## Description of the
 data and file structure Microclimate data (temperature and relative
 humidity) logged every 30 minutes in tree canopies in the middle of a
 mapped neighbourhood.  ### Files and variables #### File:
 AFEX_microclimate_HalfHourObs_revised.csv **Description:**  #####
 Variables * Logger_ID: * ID for logger - relates to Sample_code which is
 the identifier for the neighbourhood and the relevant neighbourhood
 metrics * Year: * Year of logged value * Month: * Month of logged value *
 Day: * Day of logged value * Hour: * Hour of logged value * Minute: *
 Minute of logged value * Timestamp: * Timestamp of logged value * Temp: *
 Temperature, degrees celsius * RH: * Relative humidity, % * Sample_code: *
 Identifier of neighbourhood, which relates to a separate published dataset
 with neighbourhood metrics (Dryad Digital Repository, 
 [https://doi.org/10.5061/dryad.tmpg4.f53b](https://doi.org/10.5061/dryad.tmpg4.f53b)) * Lat: * Latitude of logger * Long: * Longitude of logger * VPD: * Vapour pressure deficit, kPa * season: * Season of logged value * Plot:  * Treatment plot that the neighbourhood is located in ## Code/software Microsoft Excel