Heavy Metals in Sediments of the Upper Hawkesbury‐Nepean River

There is little published information on heavy metals in surficial sediments of the upper Hawkesbury‐Nepean River in central New South Wales, Australia. In the current investigation, the fine fraction (<62.5 µm) of 90 sediment samples taken from this section of the river was analysed by flame‐Atomic Absorption Spectroscopy for nine heavy metals (Ag, Cd, Pb, Zn, Cu Co, Fe, Ni and Mn) to determine background and enrichment. Sediment in the upper Hawkesbury‐Nepean River is not heavily polluted by heavy metals. Maximum enrichment over background for Ni and Ag, Cd, Pb, Zn, Cu and Mn is 3x, 5.7x, 6x, 6.7x, 12x and 13.6x, respectively. Mean heavy metal concentrations for this, the upper section of the river, are about half the mean values for the Hawkesbury River between Windsor and Broken Bay in the lower, estuarine section of the river. The highest Cu, Pb and Zn concentrations (214, 108 and 334 mg kg^?1, respectively) occur in surficial sediments in Peachtree Creek at Penrith and the Nepean River near Jacksons Lane, Castlereagh. These metal concentrations are possibly associated with industrial activity at Penrith. Two of the six sewage treatment plants on the upper Hawkesbury‐Nepean River are associated with high metal concentrations (Cu, Zn, Fe and Mn) in sediments, that is, the West Camden and Penrith sewage treatment plants. Other possible sources of heavy metals are coal mining and washing which occurs at several places in the upper catchment. The highest Cd, Co and Fe concentrations (1.7, 27.6 mg kg^?1 and 4.81%, respectively) were found in sediments 400 m downstream of the Nepean Dam and the highest concentrations of Ni and Mn (54 and 790 mg kg^?1, respectively) were located in sediment from the Nepean River at Moresby Hill Road Bridge, near Robertson and at the Avon Dam Road Bridge. The source of these metals is unknown.     

Earliest Evidence for the Ivory Trade in Southern Africa: Isotopic and ZooMS Analysis of Seventh–Tenth Century <Emphasis Type="SmallCaps">ad</Emphasis> Ivory from KwaZulu-Natal

KwaGandaganda, Ndondondwane and Wosi were major Early Farming Community settlements in what is today the KwaZulu-Natal province of South Africa. These sites have yielded, among other remains, abundant evidence of ivory and ivory working dating to the seventh–tenth centuries ad, pre-dating by approximately 200 years the better-known ivory artefacts from sites in the Limpopo River Valley and surrounding regions. We report the results of carbon, nitrogen and strontium isotope analysis to explore the origins and procurement of this ivory, in combination with Zooarchaeology by Mass Spectrometry (ZooMS) to identify the species of animals from which it was derived. All of the ivory studied using ZooMS was elephant, despite the presence of hippopotamus remains on all three sites. Some ivory was probably obtained from elephant herds that lived close to the sites, in the densely wooded river valleys favoured by both elephants and early farmers. Other material came from savannah environments further afield. Ivory found at these three sites was drawn from different catchments, implying a degree of landscape/resource partitioning even at this early stage. These communities clearly invested substantial effort in obtaining ivory from across the region, which speaks to the importance of this commodity in the economy of the time. We suggest that some ivory items were for local use, but that some may have been intended for more distant markets via Indian Ocean trade.     

Practices of Solidarity: Opposing Apartheid in the Centre of London

International solidarity is frequently presented as an asymmetrical flow of assistance travelling from one place to another. In contrast, we theorise the more complex, entangled and reciprocal flows of solidarity that serve to enact social change in more than one place simultaneously. The international campaign against apartheid was one of the most widespread, sustained social movements of the last century. This paper examines the spatial practices of the Non‐Stop Picket of the South African Embassy in London (1986–1990). Drawing on archival and interview material, we examine how the Picket produced solidarity with those resisting apartheid in South(ern) Africa. We argue that how the need for anti‐apartheid solidarity was framed politically cannot be understood in isolation from how it was performed in practice. The study of solidarity is enriched by paying attention to the micropolitics of the practices through which it is enacted and articulated through key sites.     

Bühnemann,Gudrun, The Iconography of Hindu Tantric Deities

Indo-Iranian Journal -