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571.
The first rural women's network in New South Wales: seventy years of the country women's association
Elizabeth Kenworthy Teather∗ 《The Australian geographer》1992,23(2):164-176
The Country Women's Association of NSW (CWA) is the main voice of rural women in the state. It has been the biggest women's organisation in NSW until very recently. Its significant contribution to rural community development has been overlooked. After its foundation in 1922, the CWA established a widespread women's network, as well as many facilities for women and children. The necessary fund‐raising activities required the organisation of regular social activities in country towns. The CWA has always affirmed women's traditional gender roles, and it has never challenged the male hegemony typical of rural Australia. By contributing to the improvement of rural conditions, to the stability of family life and to local social activities, the CWA has helped to develop the rural economy as well as local and national identity. It has helped women put down roots in country areas. Its future role needs to be defined in the context of the difficult economic situation, and of the changes in gender roles, in rural NSW. 相似文献
572.
Dr. Elizabeth M. Thomas-Hope 《GeoJournal》1992,26(1):75-79
Human migration has contributed to the redistribution of diseases from regions where they were endemic, thereby creating new areas where the task of control and management has become necessary. This is the case with respect to the major haemoglobinopathies — sickle cell anaemia and thalassaemia — in the United Kingdom since World War II. On the one hand, the great cultural diversity of the immigrant population presents an important challenge in delivering health care to the populations at risk of the diseases. On the other hand, the spatial concentration of these populations is one of the greatest advantages in the management of the disorders, since access to centrally located services can be optimized.The case of health care relating to the major haemoglobinopathies in the United Kingdom raises practical and theoretical questions about the most effective health care delivery models for ethnic minority needs. In turn, this issue has important implications for decisions concerning national and regional budgetary priorities in the health service and the position of minority medicine in the allocation of resources. 相似文献
573.
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575.
Male blue crabsCallinectes sapidus Rathbun were allowed to forage on six size classes of the Atlantic rangia clam,Rangia cuneata (Sowerby), in laboratory squaria under conditions of restricted or unrestricted prey size availability. Prey profitability (energy gained divided by handling time) decreased as prey size increased. Crabs preferred smaller clams (1–2 cm long, then 2–3 cm long), as predicted by an energy maximization model. Under conditions of restricted prey sizes (nonreplacement experiments), when the smaller clams were no longer available, crabs tended to choose progressively larger clams. Crabs did not exhibit selective feeding behavior among clams larger than 3 cm long. For the range of crab sizes tested (71–167 mm carapace width), there was no correlation between crab carapace width and the mean clam size that was eaten. 相似文献
576.
The pollution effects of cage aquaculture represent an external cost to society, and the challenge for environmental economists has been to estimate the magnitude of these costs and to suggest ways in which they can be mitigated or ‘internalised’. One possible mitigation strategy involves the development of integrated production systems based on polyculture, and this paper examines the financial viability of such a system that integrates the farming of salmon and mussels. The results demonstrate the commercial potential of an integrated salmon–mussel production system under present market conditions, but highlight the critical role played by future price trends. 相似文献
577.
578.
Amy C. Macken Nathan R. Jankowski Gilbert J. Price Erick A. Bestland Elizabeth H. Reed Gavin J. Prideaux Richard G. Roberts 《Quaternary Science Reviews》2011,30(19-20):2690-2702
Cave deposits of infill sediments and associated vertebrate fossils provide a valuable source of information on terrestrial palaeoenvironments, climatic conditions and palaeocommunities. In the deposits of the Naracoorte Caves World Heritage Area, such records span the last 500 ka and are renowned for their rich, diverse vertebrate assemblages. Previous research into the Grant Hall deposit of Victoria Fossil Cave suggested that it may preserve the only peak last interglacial (ca. 125 ka) faunal community within the World Heritage Area. The current work tested this existing model for the age of faunal remains from Grant Hall using multiple techniques. Physical and geochemical properties of the visually homogeneous sediments were analysed at regular intervals through the sequence to establish meaningful stratigraphic divisions and sediment provenance. Optically stimulated luminescence dating of individual quartz grains indicates that sediments accumulated in Grant Hall from 93 ± 8 to 70 ± 5 ka. Minimum ages provided by U/Th dating of fossil teeth (72.3 ± 2.2 to 38.2 ± 0.8 ka) are consistent with the luminescence chronology, and show that the deposit represents a more recent faunal accumulation than previously modelled for the site. U/Th ages on calcite straws within the deposit are significantly older than the sediments and fossil teeth (>500 to 186.4 ± 1 ka). As such they provide no further constraint on the chronology of the deposit but do indicate that speleothem deposition was active over much of the Middle Pleistocene. Sedimentary analyses resulted in the identification of five depositional units, contrasting with previous divisions which were based only on visual observation of the sedimentary sequence. Sediments within each unit are broadly classified as sandy silts with soil structures and may be indirectly derived from the lunettes of nearby Bool Lagoon, although their ultimate provenance is unknown. As a result of this work, palaeoenvironmental reconstruction based on fossil remains in the deposit may be more accurately related to prevailing climatic and environmental conditions at the time of accumulation. It also contributes to an understanding of the temporal occurrence of regional vertebrate faunas through the Late Pleistocene, reinforcing the value of developing stratigraphically constrained chronologies for cave deposits based on multiple techniques. 相似文献
579.
Gypsum and S are applied to soils being irrigated with Na–HCO3 dominated coalbed natural gas (CBNG) produced water to protect soil structure and fertility. Wyoming law requires beneficial use of produced water and irrigation with CBNG produced water in the semi-arid Powder River Basin is becoming more common. Strontium isotopes were used to evaluate the effectiveness of the gypsum and S applications in preventing sodification of these irrigated soils. The isotope ratio of Sr on the cation exchange complex of irrigated soil falls between that of the gypsum amendment (0.7074) and that of local soil (0.712–0.713). Strontium isotopes indicate that, to a depth of 30 cm, as much as 50% of the Sr on the irrigated soil cation exchange sites originated from the applied gypsum amendment on a field irrigated for 3 a. This was also true to a depth of 5 cm on a field irrigated less than 1 a. Strontium isotope ratio measurements of vegetation illustrate plant utilization of Sr from gypsum amendments, thereby reinforcing the conclusions about the presence of Sr from gypsum on the soil’s exchange sites. This Sr tracing technique may be useful in a wide variety of settings where monitoring soil health is necessary, especially in settings where poor quality water is used for irrigation: a more common occurrence as demand for fresh water increases. 相似文献
580.
Margaret R. Mulholland George E. Boneillo Peter W. Bernhardt Elizabeth C. Minor 《Estuaries and Coasts》2009,32(6):1176-1194
To determine the roles of dissolved organic matter in the onset, duration, and decline of blooms of the “brown tide” pelagophyte,
Aureococcus anophagefferens, nutrient and microbial dynamics, heterotrophic and autotrophic carbon (C) and nitrogen (N) uptake, and peptide hydrolysis
were compared in natural populations: (1) seasonally, among physically similar sites in a mid-Atlantic coastal lagoon, Chincoteague
Bay, (2) at an individual site as a bloom initiated, developed, and declined, and (3) in whole versus size-fractionated water.
Throughout the year, urea was the dominant form of N taken up at both bloom and nonbloom sites. C acquisition in the A. anophagefferens (1.2–5.0 μm) size fraction was dominated by bicarbonate uptake during bloom initiation but organic C compounds were taken
up later during and after the bloom. Bacterial productivity was enhanced during and just after the bloom and bacterial abundance
was four times higher at the bloom versus nonbloom site. 相似文献