Human and Natural Controls on the Accumulation,Acidification and Drainage of Pyritic Sediments: Pearl River Delta,China and Coastal New South Wales

There is increasing concern about environmental impacts of acidic drainage from acid sulphate soils on Holocene estuarine flood plains. Acidity derives from oxidation of iron pyrite in the sediments. Natural factors determine concentrations and distributions of pyrite accumulations, but human activities have reduced pyrite accumulation in the Pearl River Delta with land use practices increasing terrestrial sediment discharge. Large freshwater discharges and management techniques have enabled sustainable use of these soils. High concentrations of pyrite occur in many estuarine flood plains of Australia because of relatively greater marine inputs. Drainage of these soils enhances pyrite oxidation and estuarine acidification, which is associated with fish-kills. For sustainable development, the problems of acid sulphate soil drainage must be recognised and overcome.     

Estuarine Acidification: Impacts on Aquatic Biota of Draining Acid Sulphate Soils

Acid sulphate soils form when iron pyrite oxidises to sulphuric acid on atmospheric exposure, lowering soil pH below 4. In the Richmond River estuary, northern New South Wales, flood mitigation, drainage works and floodplain excavations have augmented acid sulphate soil formation by increasing pyrite availability for oxidation. These engineering works have facilitated the transport of acidified water and have impeded recovery from tributary acidification. The increased frequency and duration of acidification are associated with elevated concentrations of inorganic monomeric aluminium and dissolved iron, and major iron hydroxide precipitation, with deleterious effects on exposed aquatic biota and habitat. Fish kills and an outbreak of epizootic ulcerative syndrome (EUS) have been recorded from acidified sites in the estuary.     

Random Time Sampling

Random Time Sampling is an innovative data collection method which has potential for adaptation and use by geographers. Individual pocket-sized programmable beepers were used in a pilot study of the uses of time by older households and older people's attitudes to different activities. Random beeps were used to prompt individuals living in eleven Melbourne suburbs to record time use data in diaries over a period of a week. The method proved extremely effective and reliable, and many participants reporting that they enjoyed the exercise.     

INDUSTRIAL CENTERS AND REGIONAL GROWTH IN THE PRESENCE OF LOCAL INPUTS*

ABSTRACT. A large proportion of regional production takes place in nontraded goods and services. In addition, significant productivity increases can be observed in some segments of this sector. Starting from these two empirical observations we construct a model of growth in a two-region setting with factor mobility. The growth process is based on endogenous technological change in the nontraded input sector, whose output serves as an input in the production of one of the two final goods, the so-called industrial good. We consider two extreme cases, one with locally limited, the other with interregional knowledge spillovers. Conditions are established under which interior solutions with production of local inputs and steady-state growth in both regions result, and others under which we find a core-periphery pattern with growth concentrated in one region only. The stability of the equilibria is discussed by considering the transition processes. Finally, it is shown that catching-up as well as leapfrogging may occur, if new technologies become available.     

Bird remains from the archaeological site of Guinea (El Hierro,Canary Islands)

The first data on bird hunting by the ancient people from El Hierro island are given here. Ninety-three bones have been examined from a cave situated in the archaeological site of Guinea. The majority of the bones are broken, burned and some of them have cuts showing human exploitation. There are species that have been eaten from the lower levels to the present day (Calonectris diomedea, Columba sp. and Corvus corax), one species that does not now live on El Hierro (cf. Pyrrhocorax pyrrhocorax), and an extinct species (Coturnix gomerae). © 1997 John Wiley & Sons, Ltd.     

An evaluation of the site specificity of soil elemental signatures for identifying and interpreting former functional areas

Soil multi-element analysis is now a routine technique employed to help answer questions about space use and function in and around archaeological sites. The pattern of enhancement of certain elements, including P, Pb, Ca, Zn, and Cu, has been shown by numerous studies to correlate closely with the archaeological and historical record. Interpretation of these soil signatures, however, has generally been more problematic. One approach to the problem has been the use of ethnographic or “known” sites to guide interpretation, but how confidently can results from one site be extrapolated to another? This study of abandoned farms tests the site specificity of soil multi-element signatures of past space use through the use of discriminant models. Data analysis suggests that one to one comparisons of similar sites are much less accurate (38% accuracy) than comparisons based on a wider range of sites (59.3% accuracy), even when the latter have contrasting geology. The results highlight the importance of individual anthropogenic practices during occupation and abandonment in the development of diagnostic soil geochemical signatures.     

The application of numerical techniques to insect assemblages from the site of Stóraborg,Iceland

The problems of interpretation of many overlapping species lists of fossil assemblages are discussed using the example of insect faunas from a late medieval farm site in southern Iceland. Numerical techniques were employed, principally those available within the CLUSTAN package, and it was concluded that a considerable refinement in interpretation was achieved. Such quantitative procedures are suitable for groups other than fossil insects but their employment cannot be regarded as a substitute for, rather than an adjunct to, a sound ecological approach.