31 resultados para 770402 Land and water management


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One of the most significant sources of water wastage in Australia is loss from small storage dams, either by seepage or evaporation. Over much of Australia, evaporative demand routinely exceeds precipitation. This paper outlines first, methodologies and measurement techniques to quantify the rate of evaporative loss from fresh water storages. These encompass high-accuracy water balance monitoring; determination of the validity of alternative estimation equations, in particular the FAO56 Penman- Monteith ETo methodology; and the commencement of CFD modeling to determine a 'dam factor' in relation to practical atmospheric measurement techniques. Second, because the application of chemical monolayers is the only feasible alternative to the high cost of physically covering the storages to retard evaporation, the use of cetyl alcohol-based monolayers is reviewed, and preliminary research on their degradation by photolytic action, by wind break-up and by microbial degradation reported. Similarly, preliminary research on monolayer visualisation techniques for field application is reported; and potential enhancement of monolayers by other chemicals and attendant water quality issues are considered.

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Soils under irrigated agriculture are a significant source of nitrous oxide (N2O) owing to high inputs of nitrogen (N) fertiliser and water. This study investigated the potential for N2O mitigation by manipulating the soil moisture deficit through irrigation scheduling in combination with, and in comparison to, using the nitrification inhibitor, 3,4-dimethylpyrazole phosphate (DMPP). Lysimeter cores planted with wheat were fitted with automated chambers for continuous measurements of N2O fluxes. Treatments included conventional irrigation (CONV), reduced deficit irrigation (RED), CONV-DMPP and RED-DMPP. The total seasonal volume of irrigation water applied was constant for all treatments but the timing and quantity in individual irrigation applications varied among treatments. 15N-labelled urea was used to track the source of N2O emissions and plant N uptake. The majority of N2O emissions occurred immediately after irrigations began on 1 September 2014. Applying RED and DMPP individually slightly decreased N2O emissions but when applied in combination (RED-DMPP) the greatest reductions in N2O emissions were observed. There was no effect of treatments on plant N uptake, 15N recovery or yield possibly because the system was not N limited. Half of the plant N and 53% to 87% of N2O was derived from non-fertiliser sources in soil, highlighting the opportunity to further exploit this valuable N pool.

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A ban on grazing, particularly by small ruminants, forms an important component of the Forest Policy and Joint Forest Management arrangements in India. Some caste groups keep larger number of small ruminants than the others. It is considered as a social trait that is sought to be corrected through extension efforts. This paper analyses the livestock structure of households by using a model of household behaviour based on profit maximisation. It shows that landholding plays a crucial role in livestock structure of households and because certain caste groups have smaller landholding they tend to keep small ruminants that can feed on the common lands and forest areas. The policy of a ban or restriction on grazing adversely affects such caste groups who therefore come to resent it.

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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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1. Disturbance and anthropogenic land use changes are usually considered to be key factors facilitating biological invasions. However, specific comparisons of invasion success between sites affected to different degrees by these factors are rare.

2. In this study we related the large-scale distribution of the invading New Zealand mud snail (Potamopyrgus antipodarum) in southern Victorian streams, Australia, to anthropogenic land use, flow variability, water quality and distance from the site to the sea along the stream channel.

3. The presence of P. antipodarum was positively related to an index of flow-driven disturbance, the coefficient of variability of mean daily flows for the year prior to the study.

4. Furthermore, we found that the invader was more likely to occur at sites with multiple land uses in the catchment, in the forms of grazing, forestry and anthropogenic developments (e.g. towns and dams), compared with sites with low-impact activities in the catchment. However, this relationship was confounded by a higher likelihood of finding this snail in lowland sites close to the sea.

5. We conclude that P. antipodarum could potentially be found worldwide at sites with similar ecological characteristics. We hypothesise that its success as an invader may be related to an ability to quickly re-colonise denuded areas and that population abundances may respond to increased food resources. Disturbances could facilitate this invader by creating spaces for colonisation (e.g. a possible consequence of floods) or changing resource levels (e.g. increased nutrient levels in streams with intense human land use in their catchments).

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Implementation of integrated catchment management (ICM) is hampered by the lack of a conceptual framework for explaining how landowners select farming systems for their properties. Benefit–cost analysis (a procedure that estimates the costs and benefits of alternative actions or policies) has limitations in this regard, which might be overcome by using multiple-criteria decision analysis (MCDA). MCDA evaluates and ranks alternatives based on a landowner's preferences (weights) for multiple-criteria and the values of those criteria. A MCDA approach to ICM is superior to benefit–cost analysis which focuses only on the monetary benefits and costs, because it: 1) recognizes that human activities within a catchment are motivated by multiple and often competing criteria and/or constraints; 2) does not require monetary valuation of criteria; 3) allows trade-offs between criteria to be measured and evaluated; 4) explicitly considers how the spatial configuration of farming systems in a catchment influences the values of criteria; 5) is comprehensive, knowledge-based, and stakeholder oriented which greatly increases the likelihood of resolving catchment problems; and 6) allows consideration of the fairness and sustainability of land and water resource management decisions. A MCDA based on an additive, multiple-criteria utility function containing five economic and environmental criteria was used to score and rank five farming systems. The rankings were based on the average criteria weights for a sample of 20 farmers in a US catchment. The most profitable farming system was the lowest-ranked farming system. Three possible reasons for this result are evaluated. First, the MCDA method might cause respondents to express socially acceptable attitudes towards environmental criteria even when they are not important from a personal viewpoint. Second, the MCDA method could inflate the ranks of less profitable farming systems for the simple reason that it allows the respondent to assign non-zero weights to non-economic criteria. Third, the MCDA might provide a better framework for evaluating a landowner's selection of farming systems than the profit maximization model.

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The Mekong River serves China, Myanmar, Thailand, Laos, Cambodia and Vietnam covering an area of approximately 795, 000 square kilometres and the Mekong River basin is a delicate eco-system rich in natural resources and bio-diversity. Competing demands for increasingly scarce supplies of water, the reciprocal impacts of land and water uses and inadequate governance arrangements have given rise to conflicts that has to be resolved by policy making to facilitate a process, whereby the main principles adopted in the Mekong River Agreement can be implemented.

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This study assessed the sustainability of utilising groundwater systems to
manage an aluminium smelter's fluoridated trade wastewater stream. Replacing ocean discharge of the wastewater with land irrigation is one option. Using a groundwater model (developed using MODFLOW incorporating parameter estimation software (PEST-ASP)), we found that most of the groundwater flow takes place through surface sands. Fluoride is adsorbed in these sands during the drier summer months, but desorption is rapid when winter rain flushes the aquifer. Underlying clays and other layers prevent significant contamination of the deeper aquifer.

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This article aims to investigate the need for effective exchanges between knowledge generators and knowledge users in water management. Firstly, we explore the use of adaptive management for water governance and then outline the communication issues of water-management knowledge at a regional scale. Central to this approach is the need to harness 'local' knowledge that can be used to develop community participation in local water governance. Accordingly, we propose a three-network communication model to illustrate the process and identify the issues of concern for developing place-based strategies. Since research plays a central role in knowledge generation, one of the first ways to proceed is to recognise local research and incorporate it into an inclusive decision-making process. One way to achieve this is through the development of regional networks that are openly available to all, and we explore this by focusing on the place of 'network thinking' at local scale using a newly developed regional network for local knowledge dissemination in south-west Victoria, Australia. We conclude that so far this new network is too heavily reliant upon one web-based tool and outline a broader range of strategies that can be used to achieve its aims.

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It has not been until recent times that companies throughout the world have realised the preciousness of a readily available fresh water supply. It is for this reason that such companies are implementing water management schemes to improve the efficiency in which this resource is used. Located 15km north of Townsville the Bohle quarry has provided much of the material for the infrastructure existing throughout the Townsville region. Operational since the Second World War, CSR Readymix is the site's fourth owner. Water is a precious commodity at the Bohle quarry and is used primarily for dust suppression. Environmental Protection Agency (EPA) regulations state, less than 4 g/m2/month of dust fallout beyond the boundary of the quarry is permitted.

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Ecological sustainability basically concerns environmental protection and social benefits. An ecologically sustainable development is based upon reduced energy usage, increased efficiency, and upheld social responsibility; and it should be properly evaluated by financial, environmental and social aspects. Council House 2 (CH2) is claimed to change the way of Australia approaches in ecologically sustainable design and construction. This is the ‘Six-Star design and built’ green star facility assessed by the Green Building Council of Australia (GBCA), and the 10-story city council building was completed and opened in 2006, totally A$11.3 million was invested for the sustainability features. CH2 protects the environment, when it compares with the old council house, and is expected to reduce electricity consumption by 85%; reduce gas consumption by 87%; produce only 13% of the emissions; and reduce water mains supply by 72%. In this paper, the author examines its design reports and the researches paper, in the form of knowledge base, to case-study how the sustainability, effectiveness and efficiency of CH2 work. By leveraging the existing CH2 sustainability knowledge, design and building professions can learn and imitate it in further ‘green’ design without ‘re-inventing the wheel’; facilities executives can also use the existing knowledge to identify steps to boost up the facilities’ operating efficiency.

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In July 2004 the Budj Bim National Heritage Landscape was inscribed onto the National Heritage List. The place accorded with the criterion of A. Events, Processes (in demonstrating a place of Indigenous-European colonization conflict), B. Rarity (in demonstrating the context, historical and philosophy of benevolence of Governments to Indigenous people), F. Creative or technical achievement (in demonstrating technical accomplishment in construction the system), and, I. Indigenous tradition (in demonstrating longevity and continuity of cultural practices). Such affords Budj Bim, that hosts a unique Indigenous water harvesting and aquaculture infrastructure system dating some 7,000-10,000 years within a country that the Gunditjmara have managed for some 20,000-50,000 years, national standing. Within the lands gazetted is a complex and multi-faceted system that would today be categorised as a major integrated landscape planning and catchment management scheme that includes demonstrable major site engineering, hydraulic engineering, and aquaculture and water management scientific evidence and process knowledge and application.

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Estuaries are a transition zone for fresh and saline water and sediments, providing a range of ecosystem services for the local population, infrastructure and industries located in their environs. They are also governance transition zones where jurisdictions often overlap and focused attention is often lacking. As Australia’s population continues to expand, particularly in the south, estuaries are increasingly becoming popular locations for settlement due to their picturesque surrounds and accessibility for water-based activities. This results in expanding human and industry activities and pressures along estuaries and adjacent coastal settings impacting ecosystem service delivery. The absence of dedicated national and state estuary legislation in addition to decades of poor land and waterway management decisions paints a ‘doom and gloom’ picture for temperate southern Australian estuaries. Against this backdrop, there are number of estuary ‘bright spots’ where natural resource management bodies in strong partnership with local actors are moving forward in overcoming challenges to estuary conservation. Using case studies, this paper describes the key elements for effective estuary management that can lead to improved estuary health.

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Petroleum process industries are one of the most energy and emission intensive sectors throughout the world.There are natural gas processing plant, crude oils and condensate fractionation plant, liquefied natural gas plantand liquefied petroleum gas plant etc. creates environmental pollution by processing and handling of petroleumproducts. The study critically reviewed and discussed the energy and environmental management includingpollution control of petroleum process industries of Bangladesh. They produce both gaseous (process gas, wastegas etc.) and liquid (produced water, waste oil and grease etc.) pollutants. The study found that the liquid pollutantlike waste water is more hazardous and its treatment process is highly complicated due to its higher salinity, morecorrosivity and grease contain characteristics. As part of energy management, the rational use of energy and energyflow diagram of the petroleum industry is presented. Finally, a time frame measures which can be implemented inorder to save energy is outlined. The study concluded that the rational use of energy and proper environmentalmanagement are essential for achieving energy and environmental sustainability of process industries.