A soil safari: on a quest to restore and manage grassland soils

As we jumped up and down on the bumpy roads at Kapiti Research Station and Wildlife Conservancy, our team was on a quest to map the different soil types across the conservancy. We were headed on what we coined a ‘soil safari’.

Amidst seeing herds of zebras and giraffes the team, led by doctoral candidate Fiona Pearce and accompanied by professors John Quinton and Nick Ostle from the University of Lancaster jumped out of the car every 10 minutes to assess the soil type.

They are aiming to understand how the soil types change across the ranch, developing a soil map to inform research at Kapiti on soil and grassland health.

Their overall mission: to understand how we can effectively restore and manage degraded grassland soils in southern Kenya.

Kenyan grasslands are under increasing pressure from extreme weather (drought and/or flooding), invasive species, and poor management such as overgrazing.

This can cause degradation of the soils beneath, depleting them of nutrients, carbon and life; damaging their structure (e.g. through compaction), and in severe cases causing topsoil to be lost completely through soil erosion. Soil degradation can have long term effects on grassland productivity and resilience.

‘There has been a lot of research on intensively managed grasslands in Europe and the USA, but less on tropical grasslands in semi-arid areas of east Africa. Research has also tended to focus on aboveground communities (plants) and neglect the important role of healthy soils in supporting healthy grassland ecosystems. We still don’t have a good understanding of how the soils underlying Kenyan grasslands, which are different to soils in temperate regions, might respond to different management or restoration interventions,’ said Pearce.

Conducting research to improve soil health

Understanding the importance of soils in land management decisions and policymaking is crucial in creating resilient food systems and mitigating the effects of climate change.

In her doctoral studies, Fiona is partnering with the International Livestock Research Institute (ILRI) where she will implement different interventions, such as re-seeding with different grassland species and adding organic material such as manure, to test how they affect grassland soil health.

She is advised by John Quinton, Mariana Rufino from the Technical University of Munich and Sonja Leitner from ILRI.

Photo: Kenya rangelands with cattle (ILRI/Dave Elsworth)