Responses of soil biotas to human impacts: from local to global

Abstract

Soils provide crucial ecosystem services, including supporting the majority of food production, regulating water supply and quality, along with buffering against floods and droughts. Soil fauna play a significant role in the provision of these services but, despite this, little is known about the influence of land use change on soil and leaf litter biotas and subsequent impacts on ecosystem services.

At a very local scale, a detailed study of an ash-field maple woodland partially converted to conifer plantation demonstrates the influence of environmental variables, microhabitats, and land-use on soil macrofauna. Using multivariate ordination and indicator species analysis, we found distinct species assemblages of soil and leaf litter invertebrates between microhabitats, with pronounced differences in the area converted to conifer plantation.

Such local studies can provide a wealth of detail - but additional insights can be obtained through collating and analysing pooled data from many studies to estimate the average effects of gross changes in land use and land use intensity. VJB’s PhD research, supervised by Andy Purvis, Paul Eggleton and Tom Bell, aims to develop an integrated understanding of soil biodiversity in the UK. It will combine new and existing data to develop models of how soil and litter communities will respond to predicted land use and climate change and how this will impact on ecosystem services.

We are seeking to collate published studies of soil and leaf litter biotas, focusing on UK ecosystems. Those using the same sampling method to compare sites with different land use type or intensity are particularly welcome. Data will be fed into the PREDICTS database (www.predicts.org.uk), which supports global modelling of human impacts on local diversity. All contributors will be included as authors in an open-access paper on the database and acknowledged appropriately in all publications.

Full text

Responses of soil biotas to human impacts: from local to global
Victoria J. Burton1,2, Paul Eggleton2
1Science and Solutions for a Changing Planet DTP, and the Department of Life Sciences, Imperial College London, UK
2Soil Biodiversity Group, The Natural History Museum, London, UK
INTRODUCTION
Soil fauna are significant mediators of the ecosystem services
provided by soil (Fig. 1). Despite this, soil biota are rarely included in
models of how biodiversity will respond to land use change and the
subsequent impacts on ecosystem services.
The high biodiversity of soil ecosystems is often attributed to their
spatial heterogeneity at multiple scales, but studies on the small scale
spatial distribution of soil macrofauna are rare. This study of a 7.7 Ha
woodland on the Isle of Wight, southern England demonstrates the
importance of microhabitats on soil invertebrate communities.
REFERENCES
[1] D. Carpenter et. al. (2012) Biodiversity of soil macrofauna in the New Forest: a benchmark study across a national park landscape, Biodivers. Conserv. 21, 3385–3410.
[2] R Core Team (2013) R: A Language and Environment for Statistical Computing.
[3] C.J.F. ter Braak, P. Šmilauer (2012) Canoco reference manual and user’s guide: software for ordination, version 5.0., Microcomputer Power, Ithaca, USA.
[4] T. Newbold et. al. (2014) A global model of the response of tropical and sub-tropical forest biodiversity to anthropogenic pressures, Proc. R. Soc. B, 281, 1792.
ACKNOWLEDGEMENTS
Thanks to: landowners Angela and Michael Burton, members of the Natural History Museum Soil Biodiversity Group and the PREDICTS project. Thanks also to the following who helped with
identification: Sholto Holdsworth (beetles), Paul Lee (millipedes), Mike Fox (ants), Steve Gregory (woodlice) and Emma Sherlock (earthworms). Thanks to the Watford Coleoptera Group for the
photograph of Acalles ptinoides.
Location of data sources in the PREDICTS database
Data sources related to soil in the PREDICTS database
Figure 6 proportions of PREDICTS data sources related to soil
Figure 2 Study site and sample locations
Want to contribute?
If you have suitable data I would love to hear from you!
All contributors of data I use will be included as co-authors on an
open-access paper on the database and acknowledged
appropriately in all publications.
Please talk to me, pick up a flyer or email v.burton@nhm.ac.uk
Figure 1 an earthworm in its
burrow. The activity of
earthworms reduces flood risk
by increasing water infiltration.
METHODS
Winkler bags and hand sorting as per [1] were used to extract
leaf litter and soil invertebrates, respectively, of seven major
groups in 11 microhabitats (Fig. 2). Community composition
was analysed using indicspecies package in R 3.1.0 [2] and
Canonical Correspondence Analysis or Redundancy Analysis
(RDA) as appropriate, using CANOCO 5.02 [3]
Intensive Extensive
Urban Rural
Many other studies Your study?
@SoilScholar
@SBG_nhm
#PREDICTSproject
Figure 4 Soil Biodiversity Group study sites Figure 5 the PREDICTS design
RESULTS AND DISCUSSION
Soil and litter invertebrates showed microhabitat-specific species
assemblages, with samples in the plantation area less diverse than
those in the deciduous area. Dead wood habitats had distinct leaf
litter assemblages (Fig. 3), with a high proportion of saproxylic
species.
Figure 3 RDA triplot of leaf litter invertebrates, showing microhabitats have
different species assemblages, particularly the dead wood microhabitats
This highlights the need to consider and quantify small-scale
heterogeneity when developing models of soil communities.
Samples
Plantation Deciduous
Mixed litter
Logs
Moss
Path
Stumps
Bluebells
Ivy
Coppice
Stumps
Acalles ptinoides
(ACApti)
Indicator species for mixed
litter and plantation stumps
(P= 0.01)
Oniscus asellus
(iONIase)
Indicator species for stumps
and logs
(P= 0.01)
FUTURE WORK
At a local scale this study demonstrates the impact of
land-use change (conversion of deciduous woodland to
plantation) on soil and litter invertebrates, and the high
spatial heterogeneity of these communities.
We are seeking to collate and build a database of other
studies that compare sites with different land-use types or
intensities to estimate average effects of human impacts
on soil and litter communities, using techniques developed
within the PREDICTS project (www.predicts.org.uk) [4]
(Fig 5).
This will also include unpublished data from
the Natural History Museum Soil Biodiversity
Group (Fig. 4), existing relevant data in the
PREDICTS database (Fig. 6), new data on
earthworm assemblages using Citizen
Science approaches and new data collection
on soil microbial-invertebrate interactions.