Understanding plant uptake of organic and inorganic nitrogen for optimal fertiliser application in forestry. Nitrogen (N) in soils occurs in both organic and inorganic forms. Plants can take up inorganic N - nitrate and ammonium - but, on average, these account for only 5% of the soluble N in soils. Recent evidence suggests that plants may be able to tap into some of the 95% of N that occurs in organic forms. We will investigate the importance of organic N uptake for two plantation Eucalyptus sp ....Understanding plant uptake of organic and inorganic nitrogen for optimal fertiliser application in forestry. Nitrogen (N) in soils occurs in both organic and inorganic forms. Plants can take up inorganic N - nitrate and ammonium - but, on average, these account for only 5% of the soluble N in soils. Recent evidence suggests that plants may be able to tap into some of the 95% of N that occurs in organic forms. We will investigate the importance of organic N uptake for two plantation Eucalyptus species by tracing the uptake of different N forms by bacteria, fungi and eucalypts. This information will redefine what is meant by 'available N' and will guide the development of a new test for soil N status.Read moreRead less
Risk, impact on productivity and control of Mycosphaerella infections in plantations in plantations of E. nitens and E. globulus. Mycosphaerella, a defoliating fungal pathogen of eucalypts, has the potential to change markedly the economics of plantation development. This research will explore the fundamental physiological and pathological processes associated with the disease, link these findings into established process-based models of forest plantation growth for predictive purposes and util ....Risk, impact on productivity and control of Mycosphaerella infections in plantations in plantations of E. nitens and E. globulus. Mycosphaerella, a defoliating fungal pathogen of eucalypts, has the potential to change markedly the economics of plantation development. This research will explore the fundamental physiological and pathological processes associated with the disease, link these findings into established process-based models of forest plantation growth for predictive purposes and utilise hyperspectral remote sensing techniques to scale impact from the tree to plantation level. In doing this research not only are questions of key importance to an important and growing industry sector addressed, but an innovative approach to disease impact assessment established and a skills base and methodology widely applicable to other tree and agricultural disease problems established.Read moreRead less
Determining generic indicators of stress in eucalypt leaves for application to the remote sensing of canopy condition and productivity modelling. Biotic and abiotic stresses induce generic alterations of leaf chemistry (e.g. chlorophyll, anthocyanins). We will explore the behaviour of eucalypt leaf reflectance to changes in leaf cellular chemistry and structure arising from exposure to a range of stressful factors. We will relate leaf reflectance to physiological processes using a research radia ....Determining generic indicators of stress in eucalypt leaves for application to the remote sensing of canopy condition and productivity modelling. Biotic and abiotic stresses induce generic alterations of leaf chemistry (e.g. chlorophyll, anthocyanins). We will explore the behaviour of eucalypt leaf reflectance to changes in leaf cellular chemistry and structure arising from exposure to a range of stressful factors. We will relate leaf reflectance to physiological processes using a research radiation interception model. We will report on a) the potential integration of data related to stress, into process-based models for eucalypt plantation growth and b) the exploitation of generic reflectance indicators of stress in the remote acquisition of high resolution multispectral imagery with potential to spatially quantify plantation eucalypt health.Read moreRead less
Linking environmental stress in pine plantations to bark stripping by browsers and fungal attack: developing novel options for management. The Australian forest industry, under the pressure of certification requirements, is moving towards a more integrated, reduced chemical, environmentally sustainable approach to protecting forest. Novel insights into the stress biology of pine will provide valuable information that will underpin efforts to reduce risk e.g. the matching of specific genotypes to ....Linking environmental stress in pine plantations to bark stripping by browsers and fungal attack: developing novel options for management. The Australian forest industry, under the pressure of certification requirements, is moving towards a more integrated, reduced chemical, environmentally sustainable approach to protecting forest. Novel insights into the stress biology of pine will provide valuable information that will underpin efforts to reduce risk e.g. the matching of specific genotypes to site so that pest resistance can be maintained even under environmental stress conditions. By understanding the 'attraction' factor of stressed pine to wallabies we will develop and test an urgently and nationally required diversionary feed for this browser. Lethal control involving poison is becoming increasingly restricted.Read moreRead less
Understanding and manipulating stress physiology of eucalypt seedlings to improve survival and growth. Eucalyptus globulus and E. nitens are the major species being established to meet the 2020 Vision (Anon 1999) of trebling Australia's plantation estate. Seedling mortality and/or reduced growth after planting, linked to the transition from ideal growing conditions in the nursery to stressful conditions (high drought and browsing risk) at the planting sites, significantly increase the costs of ....Understanding and manipulating stress physiology of eucalypt seedlings to improve survival and growth. Eucalyptus globulus and E. nitens are the major species being established to meet the 2020 Vision (Anon 1999) of trebling Australia's plantation estate. Seedling mortality and/or reduced growth after planting, linked to the transition from ideal growing conditions in the nursery to stressful conditions (high drought and browsing risk) at the planting sites, significantly increase the costs of plantation production. By investigating physiological mechanisms of seedlings and their responses to drought and browsing stress during establishment in the field, methods for the production of seedlings acclimated to drought or browsing stress will be developed. The research outcomes will help maximise the financial return on over $28 M per annum being invested by the 8 project partners in seedling production and planting over 80, 000 ha per year for the next 19 years to meet the requirements of Vision 2020.Read moreRead less
Cellular automata model of forest stands to predict size-class distribution and survival. Existing forest growth models predict well stand level processes such as growth. However, they provide little information on forest structure and how this affects commercial forest products, risks of growing plantations and stand dynamics that determine carbon sequestration and water-use and result in age-related decline in productivity and self-thinning. By using newly developed technology to quantify in ....Cellular automata model of forest stands to predict size-class distribution and survival. Existing forest growth models predict well stand level processes such as growth. However, they provide little information on forest structure and how this affects commercial forest products, risks of growing plantations and stand dynamics that determine carbon sequestration and water-use and result in age-related decline in productivity and self-thinning. By using newly developed technology to quantify inter-tree competition, tree level resource supply, between tree genetic differences and the importance of chance events this project will draw on complexity theory to develop an innovative model that partitions stand level production to forecast the growth and size of individual trees.Read moreRead less