Assessment of the Impact of Climate and Land Use Changes on Pastoral Livestock Farming in Boulgou Province, South-Eastern Burkina Faso

Abstract

In Burkina Faso, climate change and conversion of grazing area to cropland are the main challenge of pastoral livestock. This study seeks to examine the impact of climate and land use/cover change on pastoral livestock farming in Boulgou province between 1980 and 2013. In order to achieve this, annual rainfall and temperature data from 1980 to 2012 were statistically analysed using a simple linear regression model and standardized anomaly index (SAI) to show the long-term annual trends, and to evaluate the inter-annual fluctuations of rainfall in the study area over the period of study. In addition, onset and cessation dates were computed from daily rainfall data because of their importance to agriculture and water resources management. Also, Landsat satellite images of 1989, 2001 and 2013 as well as socio-economic data from 248 respondents were analysed. Within the period of study, annual rainfall was highly variable and this was depicted as positive or negative anomalies with standardized anomaly index (SAI) greater or less than 1.5 times the standard deviation below the 33 years mean of 818.9mm. Conversely, the annual minimum and maximum temperature show a statistically significant upward trend with a rate of change of 0.25oC and 0.24oC per decade respectively which reflects an increase 0.82oC and 0.76oC from 1980 to 2012. Although substantial increase in rainfall occurred in 1989, 1994, 2007, 2008 and 2009, such anomalies occurred only 42.4% of the time, implying that there were more dry years than wet years. In addition, the analysis of daily rainfall data showed that, on the average, the onset and cessation dates were 9th June and 7th October, depicting a delay, in comparison to the long term average of mid-May and October. The interpretation of the classified Landsat images revealed an increase in cropland from 20.5% to 36.7% in 1989 and 2013 respectively. This resulted mainly from the conversion of woody savannah and shrub and grass savannah. The socio-economic survey suggests that most of the agro-pastoralists (about 73.4%) had observed that temperature had changed compared with rainfall amount (1.2%). In addition, 95.2% of the respondents observed that the frequency of the rains had decreased. The survey corroborated the results obtained from the analyses of climate and Landsat data used for the study. The respondents believe that climate is changing for the worst and is having negative impacts on crop and pastoral livestock through reduction in crop yield, fodder quantity and quality, water availability, animal production and reproduction, increasing of animal morbidity and mortality. Consequently, in order to tackle the combined impacts of climate variability /change and land use change, they practise local adaptation measures that include the use of crop residue (98.4%), vaccination (91.9%), the adoption of agro-pastoralism (89.5%), using concentrated livestock feed (80.6%), herd destocking (44.8%) and use of woody forage (42.3%). In addition to these, improvement of grazing areas, availability of information and technical training on new adaptation technologies acquired from the NGOs and government agencies can successfully reduce the vulnerability of agro-pastoralists.