Modelling human impacts on the Tasmanian wedge-tailed eagle (Aquila audax fleayi)

The wedge-tailed eagle is Australia’s largest bird of prey and one of the largest eagles in the world. Aquila audax fleayi is an endemic Tasmanian subspecies isolated for 10,000 years from the nominate subspecies on the Australian mainland. The Tasmanian wedge-tailed eagle is classified nationally and at a State level as endangered due to its small number of breeding pairs, low breeding success and high rate of mortality from unnatural causes. The subspecies experiences mortality throughout its range from shooting, poisoning, trapping, road accidents, electrocutions and collisions with wind turbines, aircraft, fences and overhead wires, which we term ‘un-natural mortality’. A portion of the subspecies’ range is managed for timber production, which can lead to disturbance of nest sites and the loss of nest trees. We use a model of the eagle population from the Bass District in northeast Tasmania to explore the relative importance of different sources of mortality and nesting habitat loss, and the potential for mitigating impacts associated with unnatural mortality, disturbance, nesting habitat loss and human access to forests. We create a habitat map including suitable nest sites and link it to a dynamic landscape population model based on life history traits and disturbance responses. Using the program RAMAS-Landscape, we model alternative forest management scenarios, ranging from no timber harvesting and a natural wildfire regime, to scenarios prescribing native forest harvesting and regeneration and different levels of conversion of native forest to plantation under the same natural wildfire regime. The results indicate that the Tasmanian wedge-tailed eagle is sensitive to unnatural mortality, plantation establishment and native forest harvesting. The predicted decline over the next 160 years (65%) will most likely be driven largely by loss of current and potential future nest sites associated with harvesting activities, exacerbated by unnatural mortality in the wider landscape. Interventions that minimise unnatural mortality, reduce nest disturbance, and retain breeding habitat and nest sites may improve the prospects for the subspecies in the Bass District. If nest disturbance and unnatural mortality continue at the rates modelled here, the species appears to face a high risk of declining substantially in the region.     

龙游县碳化篾生产现状及其存在的问题

通过对龙游县碳化篾生产企业(业主)的调查,全县自2008年以来,发展碳化篾生产企业(业主)32家,碳化炉65只,集中分布在龙游县庙下乡、溪口镇,占全县生产企业的97％.年消耗竹材2 202万支,实现销售利润l 357.2万元,产品附加值低.在碳化篾生产过程中,产生大量的废水,年产生废水27 300 t;由于废水处理成本高,得不到及时处理,大部分生产企业乱排,给当地的水质造成严重污染.该文通过对全县碳化篾生产企业的调查分析,指出当前碳化篾生产过程中存在的主要问题,希望引起政府重视,并根据碳化篾生产的实际情况,制定有效措施,及时解决碳化篾生产过程中的一系列问题.     

广义Riesz平均的交换子

讨论了一类Ｒｉｅｓｚ平均与ＢＭＯ函数生成的交换子的Ｌ＾ｐ有界性问题。得到的结果表明在超曲面的高斯曲率不为零的条件下，与经典的Ｂｏｃｈｍｅｒ－Ｒｉｅｓｚ平均有相类似的结果。     

Indications, management, and outcome of long-term positive-pressure ventilation in dogs and cats: 148 cases (1990-2001)

OBJECTIVE: To determine outcome of positive-pressure ventilation (PPV) for 24 hours or longer and identify factors associated with successful weaning from PPV and survival to hospital discharge in dogs and cats. DESIGN: Retrospective case series. ANIMALS: 124 dogs and 24 cats that received PPV for 24 hours or longer. PROCEDURES: Medical records were reviewed for signalment, primary diagnosis, reason for initiating PPV, measures of oxygenation and ventilation before and during PPV, ventilator settings, complications, duration of PPV, and outcome. Animals were categorized into 1 of 3 groups on the basis of the reason for PPV. RESULTS: Group 1 patients received PPV for inadequate oxygenation (67 dogs and 6 cats), group 2 for inadequate ventilation (46 dogs and 16 cats), and group 3 for inadequate oxygenation and ventilation (11 dogs and 2 cats). Of the group 1 animals, 36% (26/73) were weaned from PPV and 22% (16/73) survived to hospital discharge. In group 2, 50% (31/62) were weaned from PPV and 39% (24/62) survived to hospital discharge. In group 3, 3 of 13 were weaned from PPV and 1 of 13 survived to hospital discharge. Likelihood of successful weaning and survival to hospital discharge were significantly higher for group 2 animals, and cats had a significantly lower likelihood of successful weaning from PPV, compared with dogs. Median duration of PPV was 48 hours (range, 24 to 356 hours) and was not associated with outcome. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that long-term PPV is practical and successful in dogs and cats.     

Re-evaluating Asia

Harland, Bryce Collision Course: America and East Asia in the Past and Future. da Cunha, Derek (ed.) The Evolving Pacific Power Structure. King, Peter and Kibata, Yoichi (eds) Peace Building in the Asia Pacific Region: Perspectives from Japan and Australia. Bell, Roger; McDonald, Tim and Tidwell, Alan (eds) Negotiating the Pacific Century: The ‘New’ Asia, the United States and Australia. Robison, Richard (ed.) Pathways to Asia: The Politics of Engagement.     

Out-crossing frequency and genetic analysis of hybrids between transgenic glufosinate herbicide-resistant rice and the weed, red rice

The potential of transferring herbicide resistance from transgenic rice (Oryza sativa L.) varieties to sexually compatible weeds is of paramount importance for development of effective weed control strategies. The objective of this research was to determine the genetic control and frequency of natural outcrossing between a transgenic, glufosinate-resistant rice line and a Louisiana biotype of red rice (Oryza sativa L.). Molecular and phenotypic data showed that outcrossing in field plots between a non-transgenic purple marker line and red rice did occur within one field season, but at a low rate of <1%. Similarly, molecular and phenotypic data demonstrated that glufosinate resistance was transferred from the transgenic line to the red rice biotype in the field within one year at a low frequency of 0.3%. Compared to parental lines, the transgenic-red rice hybrids were extremely late, tall, and never set seed during the normal field season. Genetic analyses in all F₂ populations showed glufosinate resistance behaved in a Mendelian fashion as a single, dominant gene. Presence of the bar gene for glufosinate resistance did not increase fitness or seed fecundity in hybrids or subsequent progeny. The genetic analyses and outcrossing results from this study suggest that an effective management program can be developed to prolong the usefulness of transgenic, glufosinate herbicide technology. This revised version was published online in July 2006 with corrections to the Cover Date.     

Genetic analysis of flowering and maturity time in high latitude spring wheat

Due to the short growing season in the high northern latitudes, the development of early maturing spring wheat (Triticum aestivum L.) cultivars is important to avoid frost damage which can lower production and quality. We investigated earliness of flowering and maturity, and some associated agronomic traits, using a set of randomly selected high northern latitude adapted spring wheat cultivars (differing in maturity) and their F₁ and F₂ crosses made in a one-way diallel mating design. The parents, and their F₁ and F₂ crosses were evaluated under field conditions over 2 years. Anthesis and maturity times were controlled by both vernalization response and earliness per se genes, mainly acting additively. Non-additive genetic effects were more important in controlling grain fill duration, grain yield and plant height. Additive × additive epistatic effects were detected for all traits studied except time to anthesis. Segregation analyses of the F₂ populations for time to anthesis indicated the presence of different vernalization response genes. Molecular genetic analyses revealed the presence of Vrn-A1 and Vrn-B1 genes in the parental cultivars. Narrow-sense heritability was medium to high (60–86%) for anthesis and maturity times but low to medium (13–55%) for grain fill duration, plant height and grain yield. Selection for early flowering/maturity in early segregating generations would be expected to result in genetic improvement towards earliness in high latitude spring wheats. Incorporation of the vernalization responsive gene Vrn-B1 in combination with vernalization non-responsive gene Vrn-A1 into spring wheats would aid in the development of early maturing cultivars with high grain yield potential for the high latitude wheat growing regions of the northern hemisphere.     

Variability in Mapping Acidification Risk Scenarios for Terrestrial Ecosystems in Asian Countries

Acidification has the potential to become a widespread problem in parts of Asia. Just how widespread this risk may be is discussed by comparing sulphur deposition to critical load estimates, taking into account neutralising base cation deposition from soil dust. Two scenarios for the sulphur emission in 2025 are used as inputs to the MATCH atmospheric transfer model to estimate sulphur deposition scenarios. Net acidic deposition using a low and high base cation deposition input is compared to a map of sensitivity of terrestrial ecosystems to acidic deposition. Two ranges of critical loads assigned to this sensitivity map are used. The variability in the maps showing risks of acidification using low and high estimates for critical loads and base cation deposition for two different development pathways is discussed. Certain areas are shown to be at risk in all cases whereas others are very sensitive to the values used to estimate risk.     

An Assessment of Mercury in the Form of Amalgam in Dental Wastewater in the United States

An assessment was conducted of the discharge from dental facilities of mercury in the form of amalgam to surface waters in the United States. Two pathways were examined – effluent from publicly owned treatment works (POTWs) and air emissions from sewage sludge incinerators (SSIs). The annual use of mercury in the form of amalgam in the U.S. is approximately 35.2 tons (31.9 metric tons). It was estimated that 29.7 tons (26.9 metric tons) of mercury in the form of amalgam are annually discharged to the internal wastewater systems of dental facilities during amalgam placements and removals. Based on the partial capture of this amalgam in conventional chair-side traps and vacuum filters, the discharge of mercury in the form of amalgam from dental facilities to POTWs was estimated to be 6.5 tons (5.9 metric tons). The discharge of mercury to surface water via POTW effluents and SSI emissions was estimated to total approximately 0.4 tons (0.4 metric tons). A cost-effectiveness analysis determined that the annual cost to the dental industry to reduce mercury discharges through the use of amalgam separators would range from 380 millionto 1.14 billion per ton.     

Changes in light attenuation during filling,stabilization and operation of a reservoir

Water, Air, &; Soil Pollution - Transformations in light attenuation (Kd) and Secchi disc transparency (SD) in Round Valley Reservoir, New Jersey, are documented over a 17 yr period...