Novel ecoacoustic approach to study the effects of tree species diversity on soil biodiversity
Soil fauna plays a crucial role in the biogeochemical cycles and ecosystem services provided by forest ecosystems, with tree species composition regulating its diversity and functionality through alterations in habitat conditions and nutrient availability. Current forest management practices, such as establishment of single-species plantations, can drastically affect soil fauna and hence forest ecosystem functioning and services. However, studying the impacts of forest management on soil biodiversity remains challenging due to restrictions imposed by traditional soil fauna sampling methods which are either laborious, destructive, expensive or focused only on specific taxa.
This project explores the potential to overcome the above challenges by monitoring soil fauna with ecoacoustics and taking advantage of an acoustic recorder, the Soil Acoustic Meter (https://soilacoustics.com/), recently developed by the CASE partner, Soil Acoustics Ltd. By measuring the amount and diversity of the sounds made by soil invertebrates, the diversity of soil fauna can be assessed in a rapid, effective and non-invasive way. While applications of ecoacoustics for monitoring of aboveground biodiversity are widespread, applicability of these approaches in soil have only recently been tested. There is therefore a need to investigate the efficacy of soil ecoacoustics in different ecosystems. Acoustic measurements of soil will be taken at the plots within the long-term Satakunta forest diversity experiments in Finland (https://www.sataforestdiversity.org/) established and managed by the primary academic supervisor, Prof Julia Koricheva. As tree species composition and diversity have been experimentally manipulated by planting tree monocultures and species mixtures, and treatments have been randomized, the effects of tree species composition and diversity could be disentangled from the confounding effects of historical environmental conditions.
The aim of the project is to apply a novel ecoacoustic approach to study the effects of tree species diversity on diversity of soil fauna and the underlying mechanisms.
The specific objectives are:
- to assess the effectiveness of the Soil Acoustic Meter to record soil biodiversity by comparing acoustic recordings and traditional methods of sampling soil fauna
- to assess the effectiveness of different acoustic indices to capture soil fauna diversity
- to assess the relative contribution of different taxonomic groups to soil acoustic diversity
- to compare soil acoustic diversity in tree species monocultures and species mixtures composed of different tree species
- to explore the role of different pathways of tree species diversity effects on soil biodiversity (e.g. via changes in litter quality, soil moisture and soil temperature)
- to study spatial associations between belowground and aboveground acoustic diversity.
The prospective student will be based at the Department of Biological Sciences at RHUL and become part of the postgrad community at the Centre for Ecology, Evolution and Behaviour (CEEB). CEEB has weekly meetings during the term times with members of different labs taking turns presenting their research or discussing new scientific papers and topics of general interest. CEEB also runs fortnightly R-group meetings aimed at supporting each other in learning and using R. The student would attend weekly individual meetings with primary academic supervisor (Prof Julia Koricheva) and lab meetings every two weeks. Meetings with the second academic supervisor and non-academic supervisors will be organized as required (initially monthly, and later ca every two months), and both academic supervisors and the primary non-academic supervisor will be attending upgrade and annual review meetings. Julia Koricheva will oversee field work for the project at the Satakunta forest diversity experiments in Finland. In addition to training provided by TREES DLA, the student would receive departmental training in safety and good practice in the lab & field, office skills for researchers, research ethics, statistics,literature retrieval and organizing citations, writing literature reviews and scientific papers, preparing a poster and giving a talk at the conference. The student would also have access to training within the RHUL Doctoral School Researcher Development Programme, which offers workshops and resources to help develop transferable and employable skills. The Department of Biological Sciences holds an annual postgraduate symposium where all PhD students give an oral presentation or present a poster about their project. These are evaluated by the members of academic staff and each student receives detailed feedback on their presentation. The department also has weekly seminars during the term time with researchers from UK and abroad presenting their work. Each seminar is followed by the informal ‘meet the speaker’ event for early career researchers which provides opportunities for networking and receiving career advice. The prospective student will also have an opportunity to collaborate with researchers within the new EU project Trees4Adapt in which Prof Koricheva is a co-I and which will be using Satakunta experiments as one of the case studies. Specifically, the prospective student will collaborate with research team from Ghent University, Belgium, who will conduct aboveground acoustic surveys in the Satakunta experiment. This provides unique opportunity to combine data on above and belowground acoustic surveys at the same plots to study spatial associations between belowground and aboveground acoustic diversity and relative impact of tree species diversity on above and belowground biodiversity.
