87 resultados para Indicators of soil quality


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Water repellent soils are difficult to irrigate and susceptible to preferential flow, which enhances the potential for accelerated leaching to groundwater of hazardous substances. Over 5 Mha of Australian soil is water repellent, while treated municipal sewage is increasingly used for irrigation. Only if a critical water content is exceeded will repellent soils become wettable. To avoid excessive loss of water from the root zone via preferential flow paths, irrigation schemes should therefore aim to keep the soil wet enough to maintain soil wettability. Our objective was to monitor the near-surface water content and water repellency in a blue gum (Eucalyptus globulus) plantation irrigated with treated sewage. The plantation's sandy soil surface was strongly water repellent when dry. For 4 months, three rows of 15 blue gum trees each received no irrigation, three other rows received 50% of the estimated potential water use minus rainfall, and three more rows received 100%. During this period, 162 soil samples were obtained in three sampling rounds, and their water content (% dry mass) and degree of water repellency determined. Both high and low irrigation effectively wetted up the soil and eliminated water repellency after 2 (high) or 4 (low) months. A single-peaked distribution of water contents was observed in the soil samples, but the water repellency distribution was dichotomous, with 44% extremely water-repellent and 36% wettable. This is consistent with a threshold water content at which a soil sample changes from water repellent to wettable, with spatial variability of this threshold creating a much wider transition zone at the field scale. We characterized this transition zone by expressing the fraction of wettable samples as a function of water content, and demonstrated a way to estimate from this the wettable portion of a field from a number of water content measurements. To keep the plantation soil wettable, the water content must be maintained at a level at which a significant downward flux is likely, with the associated enhanced leaching. At water contents with negligible downward flux, the field is water repellent, and leaching through preferential flow paths is likely. Careful management is needed to resolve these conflicting requirements.

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This paper evaluates a texture-based approach developed by Sydserff and Weetman (1999), to examine corporate annual report narratives. This is achieved by using the texture index to evaluate information content (which includes readability) in accounting narratives. Specifically, we examine the letter to shareholders of reports from Australia, Hong Kong and the United States.

We suggest a texture-based evaluation provides a robust measure of narrative quality due to the incorporation of readability and content analysis. The ability to measure content quality assists in promoting accountability, with the aim of improving usefulness of corporate
information and disclosures, and greater investor confidence in capital markets.

This paper also investigates these exploratory results to consider variations in quality between different countries. Considerable differences were found between the countries with Hong Kong reports generally superior. These tentative findings provide a small contribution to the comparative annual report literature and the emerging area of narrative evaluation.

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Despite increased concern for the health related quality of life (HRQOL) of people with disabilities, little is known about the HRQOL of children with developmental disabilities. The present study aimed to explore the HRQOL of children who were at risk or having developmental disabilities in Hong Kong. Using the parent-reported Chinese Pediatric Quality of Life Inventory (PedsQL), the HRQOL of 173 children (2–4 years) with signs of delays in development was contrasted with that of 132 children with typical development. We found that those who exhibited high risk of developing a developmental disability had significantly lower overall well-being (76.3 ± 13.7 vs. 84.2 ± 11.3; p<0.001) and psychosocial health (71.3 ± 15.6 vs. 82.5 ± 12.9; p<0.001) but not necessarily physical health. The findings are consistent with previous findings in children with different disabilities and chronic illnesses. They suggest children at risk or having DDs need help in restoring their quality of life up to the standard experienced by their healthy peers, particular in psychosocial aspects such as social functioning, emotion functioning, and school functioning.

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Four sites located in the north-eastern region of the United States of America have been chosen to investigate the impacts of soil heterogeneity in the transport of solutes (bromide and chloride) through the vadose zone (the zone in the soil that lies below the root zone and above the permanent saturated groundwater). A recently proposed mathematical model based on the cumulative beta distribution has been deployed to compare and contrast the regions' heterogeneity from multiple sample percolation experiments. Significant differences in patterns of solute leaching were observed even over a small spatial scale, indicating that traditional sampling methods for solute transport, for example the gravity pan or suction Iysimeters, or more recent inventions such as the multiple sample percolation systems may not be effective in estimating solute fluxes in soils when a significant degree of soil heterogeneity is present. Consequently, ignoring soil heterogeneity in solute transport studies will likely result in under- or overprediction of leached fluxes and potentially lead to serious pollution of soils and/or groundwater. The cumulative beta distribution technique is found to be a versatile and simple technique of gaining valuable information regarding soil heterogeneity effects on solute transport. It is also an excellent tool for guiding future decisions of experimental designs particularly in regard to the number of samples within one site and the number of sampling locations between sites required to obtain a representative estimate of field solute or drainage flux.

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Adequate, appropriate training of quality managers is essential to the development and implementation of effective quality management systems. This study reports on a survey of 235 Australian quality managers to determine their perceptions of their training and development needs, the extent to which these were being met, and their views on the future of their discipline. The study found that there was a general lack of systematization, most programs were short-term and delivered by a fragmented set of providers. Many managers had received no training in the past 5 years. While the respondents were generally satisfied with the training they had received, there was evidence that their insight into their own needs was imperfect. The respondents were divided between those who thought quality management would remain a discrete field and those who saw it being absorbed by other management systems. The challenges of developing an appropriate training and development regime in this environment are discussed.

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Research indicates that the environment has had a definite impact on consumer behaviour whereby suggesting to target consumers according to their environmental beliefs. This study investigated the consumers' green purchase behaviour using price and quality attributes as contributors to the formation of purchase intention. It attempts to construct a model that may facilitate the better understanding of green consumers' market segments through the use of an intelligent soft computing model. The model is designed to incorporate knowledge, beliefs, demographic profiles and situational variables. This potentially provides a more direct method for companies to gauge consumers' intention to purchase green products. The results showed strong preference for companies to place higher priority on reducing pollution than on increasing profitability. It highlighted different clusters that demonstrate various levels of the strength of intention to purchase and market segment profiles.

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This paper describes the development and psychometric properties of a condition-specific quality of life instrument for children with cerebral palsy (CP QOL-Child). A sample of 205 primary caregivers of children with CP aged 4 to 12 years (mean 8y 5mo) and 53 children aged 9 to 12 years completed the CP QOL-Child. The children (112 males, 93 females) were sampled across Gross Motor Function Classification System (GMFCS) levels (Level I=18%, II=28%, III=14%, IV=11%, V=27%). Primary caregivers also completed other measures of child health (Child Health Questionnaire; CHQ), QOL (KIDSCREEN), and functioning (GMFCS). Internal consistency ranged from 0.74 to 0.92 for primary caregivers and from 0.80 to 0.90 for child self-report. For primary caregivers, 2-week test-retest reliability ranged from 0.76 to 0.89. The validity of the CP QOL is supported by the pattern of correlations between CP QOL-Child scales with the CHQ, KIDSCREEN, and GMFCS. Preliminary statistics suggest that the child self-report questionnaire has acceptable psychometric properties. The questionnaire can be freely accessed at http://www.deakin.edu.ac/hmnbs/chase/cerebralpalsy/cp_qol_home.php.

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Soil erosion in developing countries is a widespread problem causing considerable economic damage. It still remains an intractable problem in many countries. Available research findings on costs of soil erosion indicate them to be high. Soil erosion continues to be a problem due to the difficulties of estimating the economic damages and attendant difficulties in developing effective control policies. This paper considers soil to be a nonrenewable resource and estimates the marginal user costs using a yield damage function. Results indicate user costs to be low for individual farms. The low user costs are due to some of the assumptions made with respect to a number of parameters such as prices of tea, costs, and technological developments. The results also indicate that marginal user costs are sensitive to prices, soil depth and soil loss.

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Field-scale remediation of oil-contaminated soils from the Liaohe Oil Fields in China was examined using composting biopiles in windrow technology. Micronutrient-enriched chicken excrement and rice husk were applied as nutrition and a bulking agent. The lipase activities of indigenous micro-organisms were analyzed, and three indigenous fungi with high lipase activities was identified. An inoculum consisting of the three indigenous fungi and one introduced (exotic) fungus was applied to four different types of oil-contaminated soils. The results showed that the inoculum of indigenous fungi increased both the total colony-forming units (TCFU) and increased the rate of degradation of total petroleum hydrocarbons (TPH) in all contaminated soils but at different rates. In sharp contrast to other studies, the introduction of exotic micro-organisms did not improve the remediation, and suggests that inoculation of oil-contaminated sites with nonindigenous species is likely to fail. On the other hand, indigenous genera of microbes were found to be very effective in increasing the rate of degradation of TPH. The degradation of TPH was mainly controlled by the compositions of aromatic hydrocarbons and asphaltene and resin. Between 38 to 57% degradation of crude oils (with densities ranging from 25,800 to 77,200 mg/kg dry weight) in contaminated soils was achieved after 53 days of operation. The degradation patterns followed typical first-order reactions. We demonstrate that the construction and operation of field-scale composting biopiles in windrows with passive aeration is a cost-effective bioremediation technology.

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This study is preliminary to ongoing investigations of soil crusts and associated invertebrates in north-west Victoria, focusing on the Little Desert National Park. Ninety quadrats from nine sites were sampled. Eighteen bryophyte species (nine mosses, nine liverworts) were identified within the quadrats. All invertebrates were from the Phylum Arthropoda. Overall abundance and diversity of invertebrates was low. While sampling in the drier months is valuable for observing the dynamics of soil crusts in this region, a more comprehensive assessment of species diversity is gained by sampling
during wetter periods.

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Objectives: To collect baseline data on the fat content of hot chips, quality (degradation) of cooking fat, deep-frying practices and related attitudes in fast food outlets in New Zealand. To identify the key determinants of the fat content of chips and quality of cooking fat. Methods: A nationally representative sample of fast food outlets (n=150, response rate 80%) was surveyed between September 1998 and March 1999. Data collected included a questionnaire, observation of cooking practices and analysis of cooked chips and frying fat. Results: Only 8% of independent operators had formal training in deep frying practices compared with 93% of chain operators. There was a wide range of fat content of chips (5%-20%, mean 11.5%). The use of thinner chips, crinkle cut chips and lower fryer fat temperature were associated with higher chip fat content. Eighty-nine per cent of chain outlets used 6–10 mm chips compared with 83% of independent outlets that used chips ≥12 mm. A wide range of frying temperatures was recorded (136–233°C) with 58% of outlets frying outside the reference range (175–190°C). As indices of fat degradation, fat acid and polar compound values above the recommended levels occurred in 54% and 5% of outlets respectively. Operators seemed willing to learn more about best practice techniques, with lack of knowledge being the main barrier to change. Conclusions and implications: Deep frying practices could be improved through operator training and certification options. Even a small decrease in the mean fat content of chips would reduce the obesogenic impact of this popular food.

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Ecologically sustainable development requires an integrated approach to environmental integrity, social equity and economic performance. Development of sustainability strategies and empowerment of communities to achieve sustainability will only be effective if progress is monitored. This project provides an opportunity to work within a regional partnership to develop indicators for measuring progress toward sustainability in the south west region of Victoria, Australia. As sustainability is contextual, local organizations have been involved in the identification of key regional values (social, environmental, economic and institutional) and in selecting indicators that can be used to assess to what extent these values are being protected, depleted or enhanced. These indicators are to be used as the basis for exploring relationships between biophysical and socio-economic indicators, to determine what can be deduced from these relationships about sustainability and whether these relationships hold at different spatial scales (catchment, regional and sub-catchment). A rigorous and systematic analysis of indicators and the relationships between them will assist in developing a tool to facilitate decision making for regional sustainability.

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The research reported in this paper represents an attempt to produce a practical, indicator-based sustainability assessment tool incorporating all these elements is based on relationships between indicators determined considering spatial influences. Through the use of an existing sustainability indicator set and data currently available, relationships will be determined using Arcview Geographic Information Systems (GIS), correlation analysis and Principal Component Analysis (PCA). Indicator interactions will be identified at two spatial scales and compared to determine impacts of changing spatial scale. Further PCA and multiple regression analyses will then be used to reduce the complexity of the indicator set. These findings will be incorporated into a practical indicator-based assessment tool through the adoption of the Analytic Hierarchy Process (AHP) combined with GIS techniques that will then be validated. Once validated the tool can be used to aid in guiding planning and decision-making regarding sustainable development in the Glenelg Hopkins catchment, Victoria; while also moving towards producing a standard set of procedures for assessing sustainability.