Insights into the environmental past of the Marrakesh High Atlas: a palaeoecological investigation of Late Glacial and Holocene sediment records from the Yagour and Tissiyyi Plateaus

Abstract

The chronological, sedimentological, palaeoecological and geochemical analysis of two Holocene sediment records establishes past environments in relation to climate, as well as periods of human occupation in the Marrakech High Atlas (Morocco). In this study, multiproxy data are presented that have obtained from the Yagour Plateau (31.31°N, 7.60°W, 2460 m a.s.l.) and the Tissiyyi Plateau (31.426°N, 7.570°W, 1950 m a.s.l.). Both sites are vital resources for modern pastoral communities, providing fodder for livestock during seasonal dry periods. Cultural regulatory systems known as Agdals manage access to the Yagour wetland and have been established since early historic times at least. The Yagour Plateau is well-known for its remarkable abundance of undated petroglyphs, which may relate to the territorial delineation of these Agdals. However, direct dating of archaeological remains is rare and the timing of human presence on the High Atlas rangelands is not well known. Information gained on the past environments and the dynamics of human presence of remote, high-elevation sites in the High Atlas may be helpful in improving the understanding of the relationships between Holocene climatic, anthropogenic and ecological signals. The temporal context of these proxy records is underpinned by a high-resolution age-depth radiocarbon chronology. We observe a slow onset of the Holocene humid period around 10.8 ka. Elevated indicators of human presence from 6.2 ka to modern times are likely indicating intermittent human presence on the Yagour Plateau since the Middle Holocene . This study supports a significant effect of the regulatory Agdal system on the exploitation of pastoral resources after 1.2 ka at the Yagour Plateau, contributing to the study of long-term human presence and climate dynamics in a sensitive mountain region at the boundary of the Atlantic and Sahara climate systems.

Date of Award	1 Aug 2023
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Philip Hughes (Supervisor) & William Fletcher (Supervisor)