What lies beneath: South Africa’s megadiversity of soil biota Part III
By Dr. Charlene Janion-Scheepers & SERG members
This is the final in a three-part blog series highlighting the rich soil biodiversity found in South Africa.
In our previous blog we discussed some key findings of our review on the rich soil biodiversity of South Africa. In this last blog we want to highlight some key conservation priorities, threats to soil biota and some future directions we think are necessary for the advancement of soil biota research in South Africa.
Threats to soil biota in South Africa
Global drivers, such as land degradation, exploitation, pollution, climate change and
biological invasions, are serious threats to South African biodiversity. For many understudied groups even the identification of invasive species are problematic, while the impact of these invasives on the indigenous species are also unknown. Climate change will probably directly and indirectly favour invasive species in all South African ecosystems, thus the identification and assessment of distributions of invasive species should become a research priority for all soil biota groups.
Other threats to soil biota include intensified land-use. The livelihoods of people in South Africa depend in many ways on the continued functioning of the soil ecosystem, thus there is an urgent need for basic biodiversity knowledge in order to facilitate the soil ecosystem research required to assess sustainability.
Conservation
Soil dwelling species are usually classified as Data Deficient in the IUCN red list criteria. This appears to be related to the limited number of soil biota researchers, difficulties in identification, and inherent logistic difficulties in surveying and sampling. Even the most basic IUCN Red List criteria require a reasonable understanding of the taxonomy and distribution of individual species. The results from our review agree with previous findings, that many taxonomic groups of soil biota could not be assessed for conservation status due to a lack of baseline data. However, exceptions do exist, and the recent First Atlas of the Spiders of South Africa provides an excellent model of what is possible. In addition, the inclusion of endemic soil biota in conservation planning should be the next step to ensure soil habitat conservation.
Future research directions
The major issues that need to be addressed were clear: funding needs to be put in place to:
Train taxonomists
Consolidate and curate existing collections for improvement of data storage and management
Capture existing data
Fill gaps identified in this paper, especially focusing on the functional roles of soil biota
Use our existing and growing expertise as a base to tackle a continental deficiency in our understanding of soil ecosystems
Use current taxonomic expertise to facilitate the development of DNA barcode libraries
Sampling areas that have been poorly studied should be a priority for future work, which includes the Nama-Karoo, Northern Cape and Eastern Cape
Fig. 1: A schematic example of an integrative sampling approach.
In South Africa, funding and expertise is required in a coordinated research framework. Successful examples of this approach have been demonstrated for Europe, such as BISQ and EcoFINDERS. The development of an integrative sampling approach to sampling soil communities (Fig. 1) should be initiated in South Africa to place taxonomic knowledge in an ecological context and develop monitoring tools to provide valuable advice for soil health management. Such an overall strategy for South African soil biota research is needed, which recognises that although different research priorities exist for each group, sharing and contrasting experiences will help advance our knowledge across the board. We see the formation of SERG as the first of many steps towards the goal of an integrative approach to soil ecosystem research in South Africa.