340 research outputs found

    Predicting off-site deposition of spray drift from horticultural spraying through porous barriers on soil and plant surfaces

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    New Zealand is a recognised leader in horticultural practices which include the use of boundary shelterbelts around orchards. These shelterbelts were primarily established to provide protection to the crop but are also an effective means of ameliorating agrichemical spray drift that may arise from the crop production area. Shelterbelt structure ranges from large trees (ranging from broad leaf to needle in structure) to hedgerows and artificial netting. The efficiency of the shelterbelt in capturing spray drift is known to depend on factors such as spray drift droplet size, wind velocity and the vegetation structure. However more specific information and models are required to define the capture efficiency to form part of a comprehensive spray drift management system

    Optimising the spatial pattern of landscape revegetation

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    The spatial pattern of landscape reconstruction makes a substantial difference to environmental outcomes. We develop a spatially explicit bio-economic model that optimises the reconstruction of a heavily cleared landscape through revegetation. The model determines the spatial priorities for revegetation that minimises economic costs subject to achieving particular improvements in habitat for 29 woodland-dependent bird species. The study focuses on the Avoca catchment (330 thousand ha) in North-Central Victoria. Our model incorporates spatial pattern and heterogeneity of existing and reconstructed vegetation types. The revegetation priorities are identified as being: sites in the vicinity of existing remnants, riparian areas, and parts of the landscape with diverse land uses and vegetation types. Optimal reconstruction design is affected by opportunity costs due to the loss of agricultural production and the costs of revegetation. 1 Centre for Environmental Economics and Policy, School of Agricultural and Resource Economics, University of Western Australia, Crawley, WA, 6009 2 Department of Primary Industries, Rutherglen, RMB 1145 Chiltern Valley Rd, Rutherglen, Victoria, 3685 3 North Central Catchment Management Authority, PO Box 18, Huntly, Victoria, 3551landscape reconstruction, biodiversity, optimisation, habitat, Environmental Economics and Policy, Land Economics/Use, Q57,

    Prioritising investment to enhance biodiversity in an agricultural landscape

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    The removal, alteration and fragmentation of habitat are key threats to the biodiversity of terrestrial ecosystems. Investment to protect biodiversity assets (e.g. restoration of native vegetation) in dominantly agricultural landscapes usually results in a loss of agricultural production. This can be a significant cost that is often overlooked or poorly addressed in analyses to prioritise such investments. Accounting for this trade-off is important for more successful, realistically feasible and cost-effective biodiversity conservation. We developed a spatially explicit bio-economic optimisation model that simulates the effect of conservation effort on the diversity of woodland-dependent birds in the Avoca catchment (330 thousand ha) in North-Central Victoria. The model minimises opportunity cost of agricultural production and cost of biodiversity conservation effort on a catchment level subject to achieving different levels of biodiversity outcome. We identify the locations and spatial arrangement of conservation efforts that offers the best value for money.Environmental Economics and Policy,

    Practical and Theoretical Underpinnings of INFFER (Investment Framework For Environmental Resources)

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    INFFER (Investment Framework for Environmental Resources) was developed to help investors of public funds to improve the delivery of outcomes from environmental programs. It assists environmental managers to design projects, to select delivery mechanisms, and to rank competing projects on the basis of benefits and costs. The design of INFFER and the activities of the INFFER projects are based on extensive experience of working with environmental managers and policy makers. This experience has highlighted a number of important practical lessons, that have strongly influenced the design and implementation of INFFER. These lessons include the need for simplicity, training and support of users, trusting relationships with users, transparency, flexibility, compatibility with the needs and contexts of users, and supportive institutional arrangements. In additions, the developers have paid close attention to the need for processes that are theoretically rigorous, resulting in a tool that deals appropriately and consistently with projects for different assets types, of different scales and durations, consistent with Benefit: Cost Analysis. The paper outlines theoretical considerations underpinning the way that INFFER deals with asset valuation, time lags, uncertainty, and the design of the metric used to rank projects.Environmental Economics and Policy,

    Lessons from implementing INFFER with regional catchment management organisations

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    Investment in natural resource management (NRM) by regional organisations in Australia has been widely criticised for failing to achieve substantial environmental outcomes. The Investment Framework for Environmental Resources (INFFER) is a tool for developing and prioritising projects to address environmental issues such as water quality and biodiversity decline, environmental pest impacts and land degradation. It aims to achieve the most valuable environmental outcomes with the available resources. During 2008 and 2009 INFFER has been implemented with a number of catchment management organisations (CMOs) throughout Australia. In this paper, we report on lessons from and implications of this experience. Data on implementation were collected in formal and informal ways from staff of organisations that were using INFFER and state agencies, including: an on-line survey, benchmarking questions at training workshops, a formal on-going monitoring and evaluation process tracking the use of INFFER by CMOs, and comments made in correspondence and informal feedback to the INFFER team. In this paper we describe issues that arise when implementing INFFER with regions and organisations, and how the INFFER team has attempted to address these. Key issues include a desire to consider the community as an asset and emphasise capacity building, a rejection of the need for targeted investment, and various difficulties associated with specific aspects of the Framework. Existing institutional arrangements, and the legacy of past institutional arrangements, remain serious barriers to the adoption of methods to improve environmental outcomes from NRM investment. A lack of rigour in investment planning has become accepted as the norm, and resistance to processes to improve rigour is common. However, many CMOs want to achieve better environmental outcomes with their limited funds, and we report on our efforts to work with them to achieve this by using INFFER.Research and Development/Tech Change/Emerging Technologies,

    Changing the direction of environmental investment in Australia: Learnings from implementing INFFER

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    Investment in natural resource management (NRM) by regional organisations in Australia has been widely criticised for failing to achieve substantial environmental outcomes. The Investment Framework for Environmental Resources (INFFER) is a tool for developing and prioritising projects to address environmental issues such as water quality, biodiversity decline, environmental pest impacts and land degradation. INFFER is an asset-based, targeted, and outcome-focussed approach to environmental investment, and as such is a very different and more rigorous approach to prioritising possible environmental projects than used previously by most catchment management organisations (CMOs) in Australia. From 2008 to 2010 INFFER has been trialled with CMOs. Evaluation and benchmarking data obtained at 2-day INFFER training sessions with seven CMOs in three eastern Australia states are reported. Before commencing to use INFFER, CMO staff are generally confident about the current decision-making processes for environmental investment used within their organisation. In some cases, this initial perception challenges their acceptance of a new approach to investment decisionmaking. Key issues when implementing INFFER include concerns about changing the direction of CMO investment, concerns about compatibility with funder requirements, and various issues associated with specific aspects of the Framework. Perceived complexity of INFFER, existing institutional arrangements, and the legacy of past institutional arrangements remain serious barriers to the adoption of methods to improve environmental outcomes from NRM investment. Despite these difficulties INFFER is being used by a number of CMOs. However, it is likely that widespread adoption of INFFER, or indeed any other transparent and robust process, will only occur with greater requirement from governments for environmental decision making by regional NRM bodies that is more focused on outcomes and cost-effectiveness.NRM investment planning, NRM investment prioritisation, regional catchment management organisations, NRM policy, environmental planning, environmental prioritisation, environmental policy, Environmental Economics and Policy, Research and Development/Tech Change/Emerging Technologies, Q50, Q58,

    Has childhood smoking reduced following smoke-free public places legislation? A segmented regression analysis of cross- sectional UK school-based surveys

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    Introduction: Smoke-free legislation has been a great success for tobacco control but its impact on smoking uptake remains under-explored. We investigated if trends in smoking uptake amongst adolescents differed before and after the introduction of smoke-free legislation in the United Kingdom. Methods: Prevalence estimates for regular smoking were obtained from representative school-based surveys for the four countries of the United Kingdom. Post-intervention status was represented using a dummy variable and to allow for a change in trend, the number of years since implementation was included. To estimate the association between smoke-free legislation and adolescent smoking, the percentage of regular smokers was modeled using linear regression adjusted for trends over time and country. All models were stratified by age (13 and 15 years) and sex. Results: For 15-year-old girls, the implementation of smoke-free legislation in the United Kingdom was associated with a 4.3% reduction in the prevalence of regular smoking (P = .029). In addition, regular smoking fell by an additional 1.5% per annum post-legislation in this group (P = .005). Among 13-year-old girls, there was a reduction of 2.8% in regular smoking (P = .051), with no evidence of a change in trend post-legislation. Smaller and nonsignificant reductions in regular smoking were observed for 15- and 13-year-old boys (P = .175 and P = .113, respectively). Conclusions: Smoke-free legislation may help reduce smoking uptake amongst teenagers, with stronger evidence for an association seen in females. Further research that analyses longitudinal data across more countries is required. Implications: Previous research has established that smoke-free legislation has led to many improvements in population health, including reductions in heart attack, stroke, and asthma. However, the impacts of smoke-free legislation on the rates of smoking amongst children have been less investigated. Analysis of repeated cross-sectional surveys across the four countries of the United Kingdom shows smoke-free legislation may be associated with a reduction in regular smoking among school-aged children. If this association is causal, comprehensive smoke-free legislation could help prevent future generations from taking up smoking

    Insect visual sensitivity to long wavelengths enhances colour contrast of insects against vegetation

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    The sensitivity of animal photoreceptors to different wavelengths of light strongly influence the perceived visual contrast of objects in the environment. Outside of the human visual wavelength range, ultraviolet sensitivity in many species provides important and behaviourally relevant visual contrast between objects. However, at the opposite end of the spectrum, the potential advantage of red sensitivity remains unclear. We investigated the potential benefit of long wavelength sensitivity by modelling the visual contrast of a wide range of jewel beetle colours against flowers and leaves of their host plants to hypothetical insect visual systems. We find that the presence of a long wavelength sensitive photoreceptor increases estimated colour contrast, particularly of beetles against leaves. Moreover, under our model parameters, a trichromatic visual system with ultraviolet (λ(max) = 355 nm), short (λ(max) = 445 nm) and long (λ(max) = 600 nm) wavelength photoreceptors performed as well as a tetrachromatic visual system, which had an additional medium wavelength photoreceptor (λ(max) = 530 nm). When we varied λ(max) for the long wavelength sensitive receptor in a tetrachromatic system, contrast values between beetles, flowers and leaves were all enhanced with increasing λ(max) from 580 nm to at least 640 nm. These results suggest a potential advantage of red sensitivity in visual discrimination of insect colours against vegetation and highlight the potential adaptive value of long wavelength sensitivity in insects
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