The project investigates Aksumite agriculture and landscape by using a geoarchaeological approach together with phytolith and charred wood analyses. The project is lead by Federica Sulas (University of Cambridge) and it is carried out in collaboration with the IMF-CSIC, University of Naples L'Orientale and Boston University.

Aksum was the capital city of a complex culture that developed during the 1st millennium AD but the archaeological record shows continuity in the occupation of the area over the past 3000 years (e.g. Munro-Hay 1991; Phillipson 1998; Fattovich et al. 2000). The economic base and forms of resource management that underlie the origin, expansion, and decline of this early state still remain unclear. The importance of Aksum lays in its history and environmental setting and it can be summarised in four main points: 

1) Aksum is at the crossroad of contrasting environments that include the arid lowlands of Sudan and Eritrea, the fertile Nile Valley, the coastal plains of the Red Sea and the great Rift Valley; 

2) the region has a long history of plant exploitation, leading to the domestication of important staple crops and plough-farming;  

3) Aksum is the centre of an ancient literate civilisation; 

4) the region is the gateway for the introduction and spread of Christianity and Islam in Africa and Aksum is second only to Armenia in the adoption of Christianity as state religion.

The region today is undergoing rapid landscape transformations due to urban development and state-sponsored agricultural programmes, and these changes are having a significant impact on the ‘traditional’ lifestyles of the rural population. Modern Aksum, UNESCO world heritage site, is situated in a buffer position between international borders, a war-prone zone where rain/crop failure and political instability are actual rather than potential threats. These conditions highlight the need for studies targeted at understanding the inter-related histories of land use and degradation. The present research is designed to advance our understanding of the long-term natural and anthropic processes at work in the ancient and present landscapes of Aksum.

Contrary to past research, which suggested environmental degradation was a significant factor in the Aksumite Period (c. 150 BC – AD 700), the first results of the geoarchaeological investigations indicate a long-term dynamic stability and tailored resource management in the Aksum area, followed by severe landscape degradation only in more recent times.  

The buried soils found across the landscape provide the first local data on the environmental history. Previously, perceptions of ancient land uses have dictated opinions on the understanding of the past and current environment. The model for environmental history argues for an increase in land clearance with an intensification of agriculture toward the late Holocene. Accordingly, this led to a socio-ecological collapse and the demise of the Aksumite Kingdom in the late 1st millennium AD (Butzer 1981; Fattovich et al. 2000 passim). This cultural and environmental narrative has found support through the palaeoclimatic reconstructions available at regional scale. At Aksum and its surroundings, despite long-term occupation, the presence of forests and subsequent land clearance are still a matter of debate.

The sequence illustrated by the geoarchaeological investigations of the slopes and river valleys north of modern Aksum suggests a different scenario. The identification of a peculiar buried soil points to a considerable landscape stability prior to and during the flourishing of Aksum. This type of soil develops on surfaces where vegetation and/or land management with favourable climate provide stability. Episodes of soil movement and erosion, a sign of instability, seem to have occurred only during the last four or five centuries. Palaeobotanical studies reveal a dominance of grass species and evidence for dicotyledonous arboreal plants associated with the buried soil, pointing to a woody grassland type of vegetation. The study also highlights the relevance of water-conservation to support rain-fed agriculture at ancient Aksum. This is in contrast with the previous hypothesis that considers complex irrigation is a prerequisite for the development of the Aksumite civilisation.

A number of research priorities have emerged for understanding the relationship between soil development, settlement distributions and the effects of Holocene climate changes and land use in this region of Ethiopian highlands. These include: 

1) dating the valley deposits sequences; 

2) investigating the extent of the fertile soils and the system of soil deposition (soil macro- and micromorphology); 

3) expanding the analysis of botanical remains to refine our knowledge of the local vegetation history (phytolith and charred wood analyses).

The new datasets will situate records of past environment and land use in the broader context of landscape development in northeast Africa, and will inform on the factors and processes that shaped the Aksum landscape over time. 

Area under investigation (from the top of Beta Giyorgis Hill to the plains of the Leto River) and the Mai Hibai sequence with details of the "burnt surface" (red box and microphotographs). Cordia africana and Acacia sp. are some of the charred wood identified from this sequence (photos by F Sulas, map by M Madella).               

Recent publications on the Aksum project

F Sulas, M Madella, C French 2009. State formation and water resources management in the Horn of Africa: the Aksumite Kingdom of the northern Ethiopian highlands. World Archaeology, 41.1:2-15.

F Sulas, C French, M Madella 2009. New geoarchaeological investigations of the valley systems in the Aksum area of northern Ethiopia. Catena - DIG 2007: Catena special issue.

Download the poster presented at the 19th Society of African Archaeologists Biennial Conference - Cultural Diversity of Africa's Past: Agriculture and Water Resources at Ancient Aksum