Thursday 21 July 2016

Judging Soils as a Climate Change Solution: Where is the evidence? My fieldwork experience under CIRCLE

Dr Shade Akinsete,  University of Ibadan,
Cohort 2 CIRCLE Visiting Fellow

Climate change! Climate change!! Climate change!!! Is soil carbon storage a solution? Soils play a key role in climate change, as they could act as sources of or sinks for carbon depending on land-use management. However, sufficient evidence must be provided for the African continent. On this note, I began my field trip in southwest Nigeria in search for some evidence. For different disciplines fieldwork connotes different things. Mine was a real field in beautifully arranged teak plantations, natural forests, and arable farm lands in Onigambari and Omo forest reserves in Oyo and Ogun States, respectively. Beautiful serene environments with clean flowing streams, jumping squirrels, skillfully carved nests, flocking birds, bustling insects and active worms. Thankfully, no snakes were on sight. All these scenes were soon masked in what was about to turn into a very busy soil sampling process. Actually, I was not out there to enjoy the view only but to collect nearly seven hundred soil samples for various laboratory analyses. Why and how did I bring this upon myself? To improve and develop my career capacity provided by rare opportunities such as the Climate Impact Research Capacity and Leadership Enhancement (CIRCLE) programme that not only targets early career researchers but also ensures a good representation of women from different aspects of learning. Also, of the good nature of my home institution, which continually seeks the growth of her faculty members.

Soil profile in arable land use (Cassava farm) Onigambari Forest Reserve, Oyo State, Nigeria

Fig.1. Some Soil profiles sampled for this study: a) Alfisol under natural forest - Onigambari Forest Reserve; b) Inceptisol under teak plantation - Onigambari Forest Reserve; c) Alfisol under arable land (cassava farm) - Omo Forest Reserve; d) Inceptisol under arable land (cassava farm) - Omo Forest Reserve
Storage of carbon (C) in soils, frequently termed ‘soil carbon sequestration’, is a mitigation strategy for reducing atmospheric greenhouse gas (GHG) emissions, especially carbon dioxide (CO2), known to contribute to global warming. So how soils are treated is extremely critical for climate change studies. Under the CIRCLE award, I will be measuring how much carbon is stored in soils under different land-use management strategies in southwest Nigeria, due to insufficient information for the global soil C database and for guiding stakeholders on appropriate future land use planning and climate change mitigation strategies.

L – R: Mr. O. Owolabi (Forest Guide); Shade Akinsete; Dr. S. Jimoh (Forest Ecologist); Dr. J. Orimoloye (Pedologist) Mr. S. Ogundele (Forest Guide) in the Teak Plantation, Onigambari Forest Reserve, Oyo State, Nigeria

I could not have traversed the forest reserves on my own without the forest guides who provided direction and guidance in these terrains. Sampling soils without some past history of land-use engenders difficulty in data interpretation. Therefore, Dr. Saka Jimoh, a forest ecologist of the Department of Forest Resources and Management, University of Ibadan, Nigeria, provided some useful history as well as identifying some of the plant species. Apart from assisting in sampling, he facilitated the network with the ministry of forestry for permission to access these reserves. Without a pedologist, identification of soil types as well as soil characterisation can be frustrating, with various colours under our foot. So on this trip, I could not have left behind Dr. Julius Orimoloye, Department of Agronomy, University of Ibadan, Nigeria. Together with him and some field assistants (graduate students of our University), the soils were identified, characterised and sampled. With the unflinching support and resilience of my team the soil sampling was completed whether it was dusk or in the actual event of heavy rainfall. In the event of future fieldwork, I will enlist this same team, whose support was total to achieve the best despite the serious fuel crisis the country was experiencing at the time of the fieldwork. Although, this fieldwork was more rugged than previous ones I had engaged in, I have no regrets because it was mission accomplished. Now, onto lab work at “Mazingira Centre; ILRI’s state-of-art environmental lab” seeking to provide the evidence……

Mission accomplished- Some members of the team