Waddell, E.H.; Chapman, D.S.

R code to reproduce analyses of exotic plant invasion in fragmented and continuous forest sites in Sabah, Malaysian Borneo, 2017

This code uses pathway modelling to look at correlations of exotic plant invasion in tropical rainforest remnants and continuous sites. Partial least squares path-modelling looks at correlations between latent variables that are informed by measured variables. The code examines the relative influence of landscape-level fragmentation, local forest disturbance, propagule pressure, soil characteristics and native community composition on invasion. The total native community is examined first. Then subsets of the native community are modelled separately, adult trees, tree saplings, tree seedlings and ground vegetation. The relationship between the native and exotic communities was tested in both directions.


Publication date: 2020-07-22

Get the data

This model code is available under the terms of the Open Government Licence

Format of the data: R code

You must cite: Waddell, E.H.; Chapman, D.S. (2020). R code to reproduce analyses of exotic plant invasion in fragmented and continuous forest sites in Sabah, Malaysian Borneo, 2017. NERC Environmental Information Data Centre. https://doi.org/10.5285/adbf6d29-ee7b-4dd1-9730-11d2308d526c

 

Where/When

Study area
Temporal extent
2017-07-21    to    2017-10-25

Provenance & quality

The fieldwork for this study took place in fragmented and continuous forest sites in Sabah, Malaysian Borneo from July to October 2017. Native and exotic plants were surveyed in a nested plot design to determine genera richness and abundance. Phylogenetic diversity was calculated for the total native community and separately for adult trees, tree saplings, tree seedlings and ground vegetation. Phylogenetic diversity, genera richness and abundance made up the 'Native community' latent variable for the pathway modelling. 'Invasion' latent variable was informed by the species richness and abundance of exotic plants found in each plot. 'Fragmentation' latent variable was informed by the number of years since first planting of oil palm, the amount of non-forest area and the forest edge to forest area ratio within a 2km radius buffer of each plot. 'Disturbance' latent variable was informed the number of large trees belonging to Dipterocarpaceae and the the average adult tree wood density per plot. "Propagule pressure' latent variable was informed the number of exotic species and individuals found outside the forest over two 100m transect in the oil palm. 'Soil characteristics' latent variable was informed by soil pH and available Phosphorus in the topsoil of each plot. Connections between latent variables were informed by ecological theory and made up the full model. This included Fragmentation influencing Disturbance, Propagule pressure, Soil characteristics, Native community and Invasion. Disturbance influenced Soil characteristics, Native community and Invasion. Soil characteristics influenced the Native community and Invasion. Both the Native community and Propagule pressure influenced Invasion only. Invasion influenced just the Native community. Non-significant connections were removed in a step-wise manner before the final path-model was produced with significant correlations.

Supplemental information

This model code is a supplement to:

Waddell, E.H, Banin, L.F., Fleiss, S., Hill, J.K., Hughes, M., Jelling, A., Yeong, K.L., Ola, B.B., Sailim, A.B., Tangah, J. and Chapman, D.S. (2020) Land-use change and propagule pressure promote plant invasions in tropical rainforest remnants. Landscape Ecology

Correspondence/contact details

Emily Waddell
UK Centre for Ecology & Hydrology
Bush Estate
Penicuik
Midlothian
EH26 0QB
United Kingdom
 enquiries@ceh.ac.uk

Authors

Waddell, E.H.
UK Centre for Ecology & Hydrology
Chapman, D.S.
University of Stirling

Other contacts

Custodian
Environmental Information Data Centre
 info@eidc.ac.uk
Publisher
NERC Environmental Information Data Centre
 info@eidc.ac.uk
Rights Holder
UK Centre for Ecology & Hydrology
 enquiries@ceh.ac.uk

Additional metadata

Topic categories
Biota , Environment , Farming , Planning / Cadastre
Keywords
Agricultural landscapes,  Agriculture Biodiversity Borneo,  Conservation set-aside,  Flora,  Forest degradation,  Forest fragmentation,  Invasive species Land cover Land use Logging,  Non-native species,  Oil palm,  Roundtable on Sustainable Palm Oil,  Soil Sustainable agriculture,  Tropical rainforest
Spatial representation type
Tabular (text)
Spatial reference system
WGS 84
Last updated
24 February 2021 17:05