Embedding Climate Futures in Spatial Planning for Subsistence Agriculture in The Angolan Central Highlands

Abstract

Intensifying climate change is becoming increasingly apparent in Southern Africa with modified precipitation patterns and increases in temperature affecting growing seasons, agricultural production, and food security for small-scale farmers. While there is a strong commitment from agricultural extension services to plan the management of climate change impacts in the region, these endeavors are hampered by a lack of knowledge on how climate scenarios will develop at a scale relevant to local communities. This is especially the case in the province of Huambo in Angola, which is particularly sensitive to climate change with a rainy and dry season, and with over 85% subsistence farming is typical of many areas of the southern African region. Developing local climate date sets from 1960 to the present day, trend detection, climatic variability, and temperature and precipitation projections were determined by statistical reduction methods using regression, correlation, and time series analysis; statistical prediction methods included integrated autoregression models and moving average (ARIMA). The outcomes indicate the emerging irregular distribution of rainfall and water scarcity issues that will be a challenge for subsistence agriculture producers. This will be further exacerbated by soils with structure and textures that have limited water holding capacity. Furthermore, evidence of soil erosion and depletion of soil nutrients associated with climate change may be additional factors contributing to a significant reduction in productivity and yield of many crops. Work on the social aspects of subsistence farming community adaptation highlights that environmental changes threaten the livelihoods of local subsistence families even when adopting different strategies and techniques of agricultural production practices to the new climate scenarios. However, rural communities that depend on subsistence XIV agriculture can adapt to changing conditions using practices that conserve agro-ecosystem resilience, e.g. by changing soil cultivation by systems using intercropping of two or more crops, maintaining soil moisture. Integration of crop and plant residues into the soil is another fundamental tool for mitigation and resilience in the conservation of soil physical characteristics that can provide organic matter to the soil and offer a variety of mechanisms for recycling nutrients. These best practices may maintain agro-biodiversity and provide smallholders with an ecosystem that supports livelihoods’ well-being. Further resilience may be built through extension services interventions that include making available agro-meteorological information and to encourage many micro-irrigation systems. In summary, these findings give a locally nuanced assessment of climate change, suggesting a continuing increase in temperature, decline in rainfall, increase in the length of the dry season, and reduction in the number of rainy days. The impact of these changes will vary with soil water holding capacity and agricultural land management mitigation measures.