Microbial quality of commercial inoculants to increase BNF and nutrient use efficiency

Commercial agricultural products are increasingly being produced and sold in the market worldwide and are claimed to have a major impact on increasing crop productivity. The main objective of this research was to characterize and assess the microbial content of inoculants obtained from different countries in order to verify whether they fulfill the claims of the manufacturers. The proliferation of the underperforming products can thereafter be prevented, and value can be added to effective products. The microorganisms contained in the commercial inoculants were isolated, purified, and identified by partial sequencing of the 16S rDNA. Results showed that the majority (about 64%) of the products contained one or several strains of contaminants and only 37% of the products could be considered as “pure.” Forty percent of the tested products did not contain any of the claimed strains but only contaminants. Rhizobial products were generally of better quality than the other PGPR-based products. Results highlight the need for better quality control systems, to ensure efficacious products reach the end users.

Preformed and sprayable polymeric mulch film to improve agricultural water use efficiency

Plastic mulch films are widely used in agriculture to enhance crop production by suppressing weeds, conserving soil water and increasing soil temperature. The majority of plastic mulch films are however not biodegradable and are typically removed after each growing season. Recovery of these plastics from the soil is difficult and can affect successive crop yields while causing substantive cost to the environment and farmers. Due to increasingly stringent regulations regarding use of non-degradable plastic in agriculture they are likely to be phased out in the near future. In the past 10 years several classes of 'biodegradable' materials have been studied but most of these films are reported to be relatively weak in mechanical properties, not efficiently degradable and cost prohibitive.More recently, researchers have turned their attention to sprayable biodegradable polymer coatings for use on soils due to their easy application and versatility. The ability to mix natural additives, plasticizers and fillers to control and improve the mechanical and biodegradation properties of the core polymeric mulch film has been the driving force behind the development of these next generation sprayable polymeric mulch films.There have been many excellent review articles and papers written about polymeric mulch film, but the developing sprayable polymer systems have not been reviewed to the same extent. This paper focusses on the research progress in the area of biodegradable and sprayable polymer mulch film with emphasis on polymer formulations, properties and application. It also discusses current research to highlight the importance, potential benefits and future challenges in developing a cost effective biodegradable sprayable film for use in production agriculture.

Application of novel technologies in water reclamation, reuse and recycle

Water reuse has become an integral element of the "total water resources planning and management" along with the other elements such as water conservation, water use efficiency and management of the allocation of existing water sources. Researchers are working actively on the following aspects of water reuse: identification and characterization of different wastewaters that could be reclaimed, development of treatment technologies and effluent standards, quantification of potential gains due to recycling and risk management. The wastewaters that can be reclaimed are domestic and industrial wastewaters, grey water, black water, stormwater and rain water and their potential reuse lies in agriculture, aquaculture, industries, non-potable use in residential and community fronts and indirect and direct potable use. The treatment of wastewater ranges from secondary treatment to advanced treatment, which produces different "Classes" of reclaimed water. This paper evaluates the current status of the research on the above-mentioned important aspects of water reuse with relevant case studies and the future demand for reuse water. The direction in which the future-reuse schemes should be formulated so that they are safe, environmentally sustainable and cost effective are also discussed.

Urban growth in arid environments : developing water sustainability indicators for Abu Dhabi (UAE)

The United Arab Emirates (UAE) face a serious water problem. It has a very dry climate, high evaporation rate, combined with large water consumption from fast growing population, economic activities and uncontrolled uses of water for irrigation. Currently, UAE has one of the largest water footprints in the world. Groundwater is overexploited. Waste water is increasingly being treated to supply non-drinking water, but it still cover a small proportion of the demand. Desalination of sea water is the main source of potable water in UAE, but the high economic cost of desalination, its intensive energy demand and the adverse effects of its effluents on the marine life are a major concern. Other factors contributing to the problem are the focus of water management policies on keep supplying the growing demand for water, the increase of the per capita water consumption, and the free water charge for most of population. This research goal is to develop a water sustainability set of indicators for the challenging context of UAE. This paper presents the first stage of the research. Based on a review of the literature, the proposed framework involves 19 indicators, divided into four categories: water availability; water quality; water use efficiency; and policy and governance. Using an integrated cause-effect approach (DSR - Driving force, State, Response), the indicators were related in terms of their interdependencies, with a holistic view of the city water cycle. A preliminary test of the indicators to Abu Dhabi as a case study allowed an evaluation of the main 'Driving force' on the system, such as the scarcity of water due to natural constraints of the region, and increasing water consumption patterns of modern society; an assessment of the current 'state', which is under serious water stress. Also it indicated some potential 'responses', such as implementing policies for increasing efficient use.

CH2 energy harvesting systems : economic use and efficiency

This paper looks at the City of Melbourne's new office development CH₂ as a case study of world class energy performance. In particular, the integrated design of conventionally independent systems has led to the potential to deliver significant savings to the Council and to deliver better environmental conditions to building occupants that in turn may contribute to satisfaction, well-being and Productivity. It is concluded that this project has the potential
to be an iconic example of effective implementation of ESD (environmental sustainable design) principles and therefore act as a demonstration project to others. Energy efficiency of more than 50% of current benchmarks for Melbourne is effected. Energy harvesting is defined as arising from squander, waste and nature, which is a new concept introduced in this paper to better describe the design decision process.

Water savings or water efficiency? Water-use attitudes and behaviour in rural and regional areas

Drought conditions in southwest Victoria, as in other regions of Australia and around the world, have caused the need to reduce water consumption to ensure security of supply into the future. To develop effective water-saving behaviour change strategies, an understanding of people's attitudes to the behaviour, including barriers stopping them from adopting the behaviour, is required. Thus, this paper explores the water-use behaviours and attitudes of rural and regional urban water users in southwest Victoria. A conceptual model of the factors impacting on water use of these users, including drivers and barriers to water saving, is developed. The factors that appear to impact on water-use behaviour not previously identified included the source of water supply (groundwater versus surface water), previous experience with water shortages and trust in the water authority and government. Also, a difference in the drivers for water saving was found, with farmers wanting to be 'water efficient' to keep their business viable and productive, while hobby farmers and residential users were 'saving water' for more altruistic reasons. These findings have implications for development of demand management strategies in this, and other, rural and regional areas. However, the conceptual model has to be tested to determine if it truly reflects factors influencing water-saving behaviour in rural and regional areas.

Use of ultraviolet C (UVC) radiation to inactivate infectious hematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV) in fish processing plant effluent

We determined the stability of infectious hematopoietic necrosis virus (IHNV) and viral hemorrhagic septicemia virus (VHSV) suspended in either fish processing plant effluent blood water (EBW) or culture media and examined the effectiveness of UVC radiation to inactivate IHNV and VHSV suspended in both solutions. Without exposure to UVC, IHNV and VHSV were maintained in 4°C blood water for up to 48 hours without significant reduction in virus titer. However when exposed to UVC radiation using a low pressure mercury vapour lamp collimated beam, IHNV and VHSV were inactivated, and the efficacy of UVC radiation was dependent upon the solution and virus type being treated. A 3-log reduction for VHSV and IHNV in culture media was achieved at 3.28 and 3.84 mJ cm-2, respectively. The UV dose needed for a 3-log reduction of VHSV in EBW was 3.82 mJ cm-2. However, exposure of IHNV in EBW to the maximum UVC dose tested (4.0 mJ cm-2) only led to a 2.26-log-reduction. Factors such as particle size, and possible association of viruses with suspended EBW particulate, were not investigated in this study, but may have contributed to the difference in UVC effectiveness. Future work should emphasize improved filtration methods prior to UV treatment of processing plant EBW at an industrial scale.

Rationale for the use of DC microgrids: feasibility, efficiency and protection analysis

Electrical power systems are undergoing highly significant changes in their structures. The emergence of renewable energy units in the power generation sector, the use of high-voltage DC in the power transmission sector, and the prevalence of islanded or integrated microgrids in the distribution sector are the strongest evidence supporting this claim. These changes are mostly the consequences of the increasing energy demand rate, climate change, and environmental challenges, as well as the high investment and maintenance cost of the previous structures. Considering these new conditions and according to the recent development in DC/DC conversion topologies and control techniques, different studies have been conducted on how and why DC microgrids outperform AC microgrids. This study discusses the feasibility of the DC microgrid system according to recent developments in power systems. The efficiency and power loss reduction in DC distribution systems are then analyzed, some of the common strategies and devices for protection systems in such networks are reviewed, and the possible and existing challenges in developing the DC microgrids are highlighted. The mathematical calculations and theories for this evaluation are presented to determine the reliable justification for selecting the appropriate microgrid systems.

Risk analysis in cost planning and its effect on efficiency in capital cost budgeting

Builds on earlier work which reported on the experience of the Hong Kong Government in using risk analysis techniques in capital cost estimating. In 1993 the Hong Kong Government implemented a methodology for capital cost estimating using risk analysis (ERA) in its public works planning. This calculated amount replaces the pre-1993 contingency allowance, which was merely a percentage addition on top of the base estimate of a project. Adopts a team approach to identify, classify and cost the uncertainties associated with a project. The sum of the average risk allowance for the identified risk events thus becomes the contingency. A study of the effect of ERA was carried out to compare the variability and consistency of the contingency estimates between non-ERA and ERA projects. The preliminary results of a survey showed a highly significant difference in variation and consistency between these groups. This analysis indicates the successful use of the ERA method for public works projects to reduce unnecessary and  exaggerated allowance for risk. However, the contingency allowance for ERA projects was also considered high. Adds data from the UK with descriptions of 41 private sector projects which fall into the non-ERA category and reflect better performance in the determining of contingency allowances.

Degradation of VOCs by phototcatalytic oxidation reactor using TiO2 pellets

Volatile Organic Compounds (VOCs) are air pollutants that come from burning fossil fuels and industrial emissions. They have potentially adverse health effects being carcinogenic and highly persistent in the environment. The use of photocatalytic oxidation to remove VOCs has the potential to be applied in indoor air quality improvement and industrial emission control. A fixed bed photocatalytic reactor was designed and built. UV black light lamps were installed in the reactor to provide a source of UV radiation. A non-film titania media as pellets were placed on the three fixed beds within the reactor. Toluene and acetone were used as indicators of VOCs during the experiment. With a flow rate of 12.75l/min, the oxidation efficiencies were obtained at four different concentrations of acetone laden gas streams ranging from 40ppm to 250ppm. It was found that the lower the acetone concentration of the untreated inlet gas, the higher the oxidation efficiency. The oxidation efficiency was in the range of 40–70% for various concentrations of untreated gases. Two concentrations of toluene laden gas stream were also tested using the same reactor. The oxidation efficiencies were found as 50% for 120ppm toluene gas and 45% for 300ppm toluene gas. It was found that the times required for toluene to reach oxidization equilibrium have been halved than for acetone gas stream. Other parameters such as flow rate and UV intensity were also altered to see their effects on the oxidation efficiency. A full spectrum scan was carried out using a Bio-rad Infrared spectrometer. It was found that the main components of the treated gas stream from the outlet of the reactor were CO2 and water along with small amount of untreated acetone. The suspected intermediates of aliphatic hydrocarbons and CO were found in very minimal amounts or undetectable. The research experiments supported that the TiO2 pellets can work effectively in a fixed bed photocatalytic reactor and achieve significant oxidation efficiencies for degradation of toluene and acetone as indicators of VOCs.

Validation of the use of input-output data for embodied energy analysis of the Australian construction industry

This paper evaluates a recently developed hybrid method for the embodied energy analysis of the Australian construction industry. It was found that the truncation associated with process analysis can be up to 80%, whilst the use of input-output analysis alone does not always provide a perfect model for replacing process data. There is also a considerable lack in the quantity and possibly quality of process data currently available. These findings suggest that current best-practice methods are sufficiently accurate for most typical applications, but this is heavily dependant upon data quality and availability. The hybrid method evaluated can be used for the optimisation of embodied energy and for identifying opportunities for improvements in energy efficiency.

Farm-level efficiency and productivity measurement using panel data: wool production in south-west Victoria

In this article we explore some issues surrounding the use of farm-level efficiency and productivity estimates for benchmarking studies. Using an eight-year balanced panel of Victorian wool producers we analyse annual variation between estimates of farm-level technical efficiency derived using Data Envelopment Analysis and Malmquist estimates of Total Factor Productivity. We find that farms change their relative rank in terms of efficiency across years. Also, unlike aggregate studies of Total Factor Productivity, we find at best erratic and modest growth, a worrying result for this industry. However, caution is needed when interpreting these results, and for that matter, benchmarking analysis as currently practised when using frontier estimation techniques like Data Envelopment Analysis.

The role of a prospective public health intervention study register in building public health evidence: proposal for content and use

Evidence-informed practice is a key component of public health and the focus of much discussion, of which the nature of evidence and how it is best gathered and appraised has formed a large part. Prospective registration of trials is now a key component of rigour and quality in clinical research and has been supported at an international level through the WHO International Clinical Trials Registry Program. This paper discusses the scope and benefits of trial registration in clinical research, including greater transparency and reduced publication bias. It then considers the potential for a Prospective Public Health Intervention Studies Register specific to the needs of public health and aspects to be included in such a register. It is argued that this initiative has the potential to facilitate increased global cooperation and efficiency in the production of high quality evidence and ultimately in improved health outcomes for populations.

Efficiency measurement of Australian dairy farms: national and regional performance

In this paper we use Data Envelopment Analysis (DEA) to estimate technical efficiency for a sample of 1742 Australian dairy farms. Bearing in mind data limitations we find that average technical efficiency is 59 per cent, but there are significant regional differences. These results reflect differences in State level milk marketing arrangements in place before dairy deregulation in July 2000 providing an ex post explanation for the changing composition of dairy farms in Australia. We also examine two important technical aspects of DEA implementation. First, how changes in model input specification alter the relative performance of farms. Second, we employ a simple bootstrap procedure to show how changes in sample size affects estimates of technical efficiency. These results have simple but important implications for the use of DEA as an industry-benchmarking tool.