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The diversity, distribution and species richness of benthic macroinvertebrate fauna as well as benthic environments were examined in the blood cockle Anadara granosa cultivations at Ban Don Bay, Suratthani Province, Southern Thailand during the summer season of April and rainy season of October in 2017. The cockle cultivations of three repeated operating ages (<5 years: S1; 5–10 years: S2; more than 10 years: S3) were selected for the study, and the sampling sites were allocated at the centre of the farm. Results indicated that there were significant differences in species number, individual number and evenness index of benthic macroinvertebrate fauna found in the two sampling seasons (p < .05) and significant differences in individual number and evenness index were found among the sampling sites (p < .05). Significant differences in pH, total phosphorus levels, sulphide levels and organic matter of sediment were found between the sampling seasons (p < .05) and differences in total nitrogen level, organic matter and clay content were found among the sampling sites (p < .05). Among the independent variables analysed, correlation analysis showed no relationship between diversity index, species richness index and evenness index and the abiotic variables (p < .05). The results of the present study suggest that the distribution and diversity variations of the benthic macroinvertebrates community fauna are not affected by all sediment parameters in various repeated cultivation of the blood cockle Anadara granosa in Bandon Bay, Suratthani Province. [ABSTRACT FROM AUTHOR]

While a range of physical and chemical taphonomic processes are known to affect archaeological shell assemblages, it has been difficult to directly quantify the effects of these degradational processes on the shell itself. Here the measurements of Anadara granosa shell features are used to derive morphometric equations for estimating expected shell weights. A cubic regression model is developed to this end, based on measurements of all shell elements of complete A. granosa valves, resulting in high predictive power. The morphometric method proposed here therefore allows for the comparison of observed and expected shell weights to determine the extent of weight loss as an indication of these processes. A case study is presented by applying these morphometric equations to a midden assemblage from northeast Arnhem Land to investigate potential bias in shell preservation. This study demonstrates the efficacy of the proposed method, and the need to assess the interaction of different taphonomic processes on a site and species-specific basis. [ABSTRACT FROM AUTHOR]

Middens and mounds dominated by Anadara granosa began in be formed on the Abydos Coastal Plain sometime between 4400 and 5300 calibrated years before present, unit while mounds appear to have ceased forming some 1800-1600 years ago. middens continued lo form until the early twentieth century or later. In some cases, the curliest of these middens and shell mounds formed on top of older middens from which Anadara granosa is totally absent, and in which Terebralia spp. (while occurring in relatively low concentrations) is the dominant shell species. Anadara granosa dominated middens (sensu lato) occur in a variety of forms across the landscape, including large shell mounds, earth mounds (or mounded shell middens), lenses of shell eroding out of well-developed dunes, and undifferentiated surface shell scatters. The large number of middens which occur throughout the region from the mid Holocene, and the volume of shell represented by these sites, point to the occurrence of significant economic and social changes from the mid to late Holocene. The Abydos Coastal Plain experienced increasing aridity, and, as a result, increased resource stress during the mid-Holocene. We suggest that the large. single species Anadara granosa middens were occupied during regular periods when large groups of Aboriginal people undertook ceremonial activities after the wet season, when resources were abundant. Changes apparent in the archaeological record, including the occurrence of large numbers of Anadara granosa dominated middens and shell mounds, increased establishment of archaeological sites and increased complexity and distance of exchange systems, came about as a result of social, economic and logistical restructuring. This in turn was the result of the effects of resource stress on local Aboriginal people over the course of the mid to late Holocene. [ABSTRACT FROM AUTHOR]

This paper reports the archaeological salvage, radiocarbon dating and analysis of seven shell midden sites located south of Port Hedland, and makes observations regarding the archaeology of the Port Hedland region and the Abydos coastal plain. The excavations revealed an almost continuous sequence of archaeological sites dating between 5250calBP and 50calBP years. These include some of the earliest and latest radiocarbon ages associated with Anadara granosa dominated middens, shell mounds and earth mounds from northwestern Australia. Where earlier researchers had suggested that Anadara exploitation in northwestern Australia, and particularly on the Abydos plain and Burrup Peninsula, was limited to between 4200 and 1600 BP, these excavations demonstrate that the exploitation of Anadara shell in the Port Hedland region was continuous from at least 4400calBP (and possibly as early as 5350calBP) until the early twentieth century. Based on a consideration of their contents and ages, it is suggested that the various forms of shell accumulations in the study area, including shell mounds, earth mounds, surface scatters and stratified lenses of shell midden, are likely to vary more as a result of site formation processes than Aboriginal people's past gathering practices. This finding has broader implications for understanding the place of Anadara shell mounds and middens in the prehistoric regional economy of northwestern Australia. [ABSTRACT FROM AUTHOR]