By Liz Ivkovich, Sustainability Office
This post is the second of our series highlighting the innovative research presented by the GCSC Seminar Series. Dr. Marc Parlange of the University of British Columbia will present his research on the landscape transformation of West African savannas on Tuesday, Sep. 13 at 4 p.m., in 210 ASB (Aline Skaggs Biology).
The rain in Burkina Faso does not follow the plow. The West African nation of Burkina Faso faces intense international pressure to plow; to transform large swaths of its rolling savannas into agricultural fields in an attempt to reduce regional food insecurity. However, according to Hydrologist Dr. Marc Parlange, plowing the savanna into fields causes large-scale landscape changes that can have unintended environmental impacts, including decreasing the annual rainfall in the region.
In his upcoming presentation at the GCSC Seminar Series, Parlange will explain his results and their impacts for international policy. He will also unpack the surprising relationship between savanna landscape and rainfall.
Parlange explains; “Basically, the rain in West Africa arrives because of convective storms.”
Convective storms occur as warm air flows over the stones and trees of the dry savannas, pushing warm, moist air parcels into the sky that become clouds, and subsequently rain. In order for these air parcels to get high enough into the atmosphere to transform into clouds, they need what Parlange describes as ‘a large, strong, sensible heat’ pushing them upward.
According to Parlange’s study, these new agricultural lands in Burkina Faso experience 10 – 30% less rain than the savannas. When the rocky landscape of the savanna is plowed for farming, the micropores in the soil that are essential for water drainage are damaged. As a result, water doesn’t drain as quickly into the soil, keeping the surface unnaturally moist. The moist soil prevents hot air from pushing the air parcels high enough to form clouds. Thus, the wetter soil of agricultural fields equals less rainfall to the whole region.
His research team hopes that communicating their results to the Swiss Government and United Nations will offer a robust scientific basis for future agricultural policy in West Africa.
“There’s still going to be pressures from the population moving into this region and wanting to start agricultural fields, but hopefully the United Nations and other policymakers will think a little bit more before they encourage large-scale transition to agriculture. They might think about more of an agroforestry system, integrating parts of the savanna with some aspects of the agriculture.”
Considering the complex relationships between each part of an ecosystem is one of the takeaways Parlange hopes people will have from his talk.
“Changing land use, changing the landscape, can have unintended consequences on the environment. Whenever we do something at large scale, whether it’s building cities or doing large-scale irrigation where there wasn’t large-scale irrigation before, if we do experiments with deforestation and so forth, there will be impacts on the environment that will manifest themselves in ways that maybe we hadn’t intended to have happen.”
Join Parlange at the GCSC Seminar Series on Tuesday, Sep. 13 to learn more.