Identifying Human and Climatic Influences on Ancient Plant Communities in Dhofar, Oman
Loading...
Date
2020-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
The Ohio State University
Abstract
Through identifying changes in plant community changes over time, we can better understand
how natural and anthropogenic processes affect vegetation. As climate changes, the natural
environment and available resources for anthropogenic use are altered. Human responses to a
changing environment include social changes like new settlement patterns or changing family
sizes. Consequently, human resource use strategies adapt to these changes, which can have
feedback effects on the natural environment. Anthropogenic influences and human presence in a
landscape are identifiable through the variations of plants present, which we can measure using
vegetation proxies. Our research uses plant fragments found within fossilized midden deposits of
desert rock hyraxes (Procavia capensis) to study anthropogenic vegetation changes in Dhofar
of Oman over the past 3,500 years BP.
The hyrax is a small herbivore that grazes in close proximity to its den, so that hyrax middens
reflect localized vegetation. From 45 middens samples, we extracted identifiable macrofossils.
We used incident light microscopy and a digital camera to compare specimens with modern
reference material. We relied on radiocarbon ages from 33 of the 45 middens to understand the
temporal shifts of vegetation patterns. To grasp what past vegetation was present in the
landscape, identified fragmented macrobotanicals were weighed and analyzed for the presence of
5 particular "indicator" species of anthropogenic activity. The "Indicatory Species Approach"
identifies particular plant communities present indicative of human's presence in a landscape.
Through statistical analysis, we recognized many distinct types and categories of species that
provided quantifiable proxies of desert vegetation while we also analyzed the ability of the
middens to capture anthropogenic activity. We conducted a canonical correspondence analysis
(CCA) and detrended correspondence analysis (DCA) for 89 identifiable fossilized botanical
species specimens in 45 different locations. The results from the DCA suggested that the
vegetation developed as an adaptation to more arid climates. For the CCA, the variables, which
are a) distance to human monuments and b) distance to freshwater, explained 26% of the species
variation. This result suggested that plant assemblages are influenced by human pressures.
Description
2020 Denman - 3rd Place, Environmental and Animal Sciences
Keywords
paleobotany, anthropogenic indicator fauna, Dhofar, pastoralism, Hyrax