Relationship between Humans and Camels in Arid Tropical Mangrove Ecosystems on the Red Sea Coast

摘要

Coastal zones of the arid tropics, where arid land is juxtaposed with mangrove and coral reef areas, show a contrast in extremes between the most unproductive land ecosystem and the most productive sea ecosystem. I analyzed resource patch accessibility and availability in arid tropical mangrove ecosystems, focusing on human-camel relationships among the Beja on the Sudanese Red Sea coast. Firstly, I made schematic over- views of the physical environment, biological environment and livestock grazing zones in a three-dimensional figure. Secondly, I elucidated the role of dromedaries (one-humped camels), outlining resource patch acces- sibility and availability by constructing a relationship web among human beings, livestock, coral reefs (the physical environment) and resource patches (the biological environment). As a result, I could show that re- source patch accessibility and availability are determined by camels’ intervention, so that resource over- exploitation in coastal zones of the arid tropics has been limited consequently. Therefore, in terms of sustainability of human resource use, the relationship between humans and dromedaries is the key interspe- cific relationship in arid tropical mangrove ecosystems.