Impact of Climate Change and Land Use/land Cover Dynamics on Small-scale Farming System in Gedaref State, Sudan

Abstract

Rainfed agriculture is generally the principal activity for the economy of Sudan. However, this sector is severely affected by climate change due to shifting in rainfall patterns, rising temperatures, and extreme weather events such as floods and droughts. Consequently, this has resulted in reduced crop production and increased hunger. Specifically, climate change coupled with changes in land use/ land cover (LULC), as a proxy for landscape structure, land fragmentation, degradation, and reduction in soil fertility have threatened small-holder livelihood in Sudan. Therefore, the aim of this study was to investigate the impacts of climate trends and LULC changes on crop production of small-holder farmers in Gedaref state, Sudan. To achieve this, four objectives were defined; i) to determine the relationship between climate trends and the level of crop yields; ii) to determine farmers’ perception of climate variability and change and their choice of adaptation measures; iii) to assess and quantify LULC changes and their intensities between 1988 and 2018, and to project LULC structure in 2028 and 2048; iv) to assess the local farmers’ perception of LULC change trends; and determine their drivers in Gedaref state. Historical records of rainfall and temperature, crop (sorghum, sesame, millet, cotton and sunflower) production, and population data for Gedaref state were obtained from Sudan Meteorological Authority, Ministry of Agriculture, and Sudan Central Bureau of Statistics, respectively. Semi-structured questionnaire, key informant interviews and focus group discussions were used to collect data on small-holder farmers' perception of climate and LULC trends. These datasets were subjected to various analysis including Mann–Kendall trend test, multiple linear regression, correlation and multinomial regression model. In addition, satellite-based data were used to map LULC changes between 1984 and 2018 using the machine learning random forest algorithm and future LULC for 2028 and 2048 utilizing the cellular automata-artificial neural network model. Trends in annual maximum and minimum temperatures significantly (p < 0.0001) increased in Gedaref state by 0.03°C and 0.05°C per year, respectively, with fluctuations in the amount of rainfall. The rainfall amount and duration of the rainy seasons were the only climatic factors that positively affected crop yields. The small-scale farmers were aware about climate change, and they used crop rotation, early cultivation and cultivation of short-maturing crop varieties as adaptation measures to climate change and variability. The analysis of LULC change showed a decline in forest and grassland cover and an increase in cropland and settlement. Local land users perceived a similar trend and ranked firewood collection, agricultural expansion, and charcoal production as the top proximate drivers, while poverty and rapid population growth were the most vital drivers for LULC changes in Gedaref landscape structure. However, future prediction of LULC showed an overall increase in cropland and settlement areas at the expense of forest and grassland areas by 2048. These findings have shown that crop yields are affected by climate change and variability and changes in LULC would significantly affect future crop production. Therefore, there is a need to raise awareness among different stakeholders, especially policymakers to provide sustainable interventions for small-holder farmers against climate and LULC changes in Gedaref state and other similar farming systems.