997 resultados para ecological opportunity


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A common approach to nature conservation is to identify and protect natural 'assets’ such as ecosystems and threatened species. While such actions are essential, protection of assets will not be effective unless the ecological processes that sustain them are maintained. Here, we consider the role of ecological processes and the complementary perspective for conservation arising from an emphasis on process. Many kinds of ecological processes sustain biodiversity: including climatic processes, primary productivity, hydrological processes, formation of biophysical habitats, interactions between species, movements of organisms and natural disturbance regimes. Anthropogenic threats to conservation exert their influence by modifying or disrupting these processes. Such threats extend across tenures, they frequently occur offsite, they commonly induce non-linear responses, changes may be irreversible and the full consequences may not be experienced for lengthy periods. While many managers acknowledge these considerations in principle, there is much scope for greater recognition of ecological processes in nature conservation and greater emphasis on long time-frames and large spatial scales in conservation planning. Practical measures that promote ecological processes include: monitoring to determine the trajectory and rate of processes; incorporating surrogates for processes in conservation and restoration projects; specific interventions to manipulate and restore processes; and planning for the ecological future before options are foreclosed. The long-term conservation of biodiversity and the wellbeing of human society depend upon both the protection of natural assets and maintaining the integrity of the ecological processes that sustain them.

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Personal passenger transport faces several challenges in the coming decades: depletion of cheap oil reserves, increasing congestion, localised pollution, the need for reduced carbon emissions and the long term goal of sustainability. One way of solving some of these problems could be to introduce comfortable, energy efficient, battery electric vehicles.

Currently, hybrid vehicles have been presented as a means to reducing the transportation related oil demand. New developments in materials and technologies have made them, cleaner and safer as well as more fuel efficient. However, hybrids will only prolong the use of oil until alternatively fuelled vehicles are developed.

One long term alternative is the battery electric vehicle (BEV). A BEV designed to be light, aerodynamic with high efficiency drive train and latest battery technology would have a performance comparable to a typical internal combustion engine vehicle (ICEV). Recent developments in virtual engineering, rapid prototyping and advanced manufacturing might enable low-cost development of niche market BEV’s designed and built in New Zealand for export markets.

This work examines the collaborative development of a twin seat BEV using new materials and latest technologies by the University of Waikato’s Engineering Department and a group of NZ and foreign companies. The car will be used to research the potential of BEVs and will also compete in the Commuter Class of the World Solar Challenge in 2007.

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Estuarine benthic assemblages are often numerically dominated by polychaetes. The limits of these populations are determined by larval, and probably to a lesser extent adult movement. A previous study (Newton 1996), indicated that planktonic polychaete larvae were very abundant over the summer months in the Hopkins River; however, the identification and source of these larvae was not known. Defining the extent of a population, and therefore the likelihood of that population recovering following a perturbation, is crucial for effective estuarine management. This study investigated both the likely source of the larvae, (i.e. estuarine or marine) and the extent of larval dispersal within and between estuaries by addressing the following questions: Which taxa produced the planktonic larvae? Are these taxa resident estuarine species? Are the larvae of different taxa evenly distributed within the estuary or do physicochemical parameters or other factors influence their abundance? Are the same larvae found in other estuaries along the coast? and Is there exchange of these larval taxa with the marine environment and other estuaries? Larvae were identified and described by culturing commonly occurring planktonic larvae until adult characteristics appeared. The spionids, Carazziella victoriensis and Prionospio Tatura, numerically dominated the plankton in the Hopkins and the spionid, Orthoprionospio cirriformia was recorded from the Hopkins, Curdies and Gellibrand estuaries. Two spionids, Carazziella sp. and Polydora sp. were identified from tidal waters. Mouth status and physicochemical conditions (salinity, temperature and dissolved oxygen) were monitored in each estuary. Whereas the Merri and Gellibrand estuaries were predominantly stratified over the sampling period, the Curdies was more often well mixed and the Hopkins varied from well mixed to stratified. The duration of mouth opening and hence the opportunity for larval exchange also varied in each estuary. The Merri River was closed for 13.5% of days over the study period, the Gellibrand River for 18.4%, the Hopkins River for 49% and the Curdies River for 71.0%. The distributions of larvae at spatial scales of metres, 100s of metres and kilometres were investigated within a single estuary. While the same larvae, C. victoriensis, P. Tatura and bivalve larvae, were found along the length of the Hopkins estuary the abundances varied at different spatial scales suggesting different processes were influencing the distribution of P. Tatura larvae, and C. victoriensis and bivalve larvae. The distribution of larvae between several estuaries was investigated by monitoring meroplankton at two sites at the mouth of each of the four estuaries approximately monthly (except for winter months). Different meroplanktonic assemblages were found to distinguish each estuary. Further, C. victoriensis and P. Tatura larvae were only recorded in the Hopkins but larvae of the spionid, Orthoprionopio cirriformia were detected in the Hopkins, Curdies and Gellibrand estuaries. The extent of larval exchange with other estuaries and the marine environment was determined by monitoring tidal waters. Settlement trays were also deployed to determine if larvae were moving into estuaries and settling but not recruiting. P. tatura larvae were not detected in the tidal waters of any estuary and while C. victoriensis and O. cirriformia were found in both flood and ebb tides there was no evidence of movement of theses taxa to other estuaries. Larvae of the spionids, Carazziella sp. and Polydora sp., were found in tidal waters of each estuary but were rarely detected in the plankton within the estuaries. Neither species was found as an adult in background cores from any estuary, nor with the exception of a few individuals in the Merri, were they detected in settlement trays in any estuary. I conclude that the source of the larvae of C. victoriensis, P. Tatura and O. cirriformia is estuarine and while C. victoriensis, and O. cirriformia move in and outh of the source estuary in tidal waters there was no evidence for movement to other estuaries. The spionids, Carazziella sp. and Polydora sp were considered to be marine and while they moved in and out of estuaries in tidal waters they did not usually settle in the estuaries. The results of this study are a crucial first step in the development of ecological models to better understand dispersal in seasonally closed estuaries that are typical of southern Australia. This study emphasises the unique physicochemical characteristics and biological assemblages within these estuaries and the need for estuarine management to reflect these differences.

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Riparian zones are a characteristic component of many landscapes throughout the world and increasingly are valued as key areas for biodiversity conservation. Their importance for bird communities has been well recognised in semi-arid environments and in modified landscapes where there is a marked contrast between riparian and adjacent non-riparian vegetation. The value of riparian zones in largely intact landscapes with continuous vegetation cover is less well understood. This research examined the importance of riparian habitats for avifauna conservation by investigating the ecological interactions contributing to the pattern of bird assemblages in riparian and adjacent non-riparian habitats. Specifically, the focus is on the bird assemblages of riparian zones and those of adjacent non-riparian vegetation types and the influence that associated differences in resource availabilities, habitat structure and conditions have on observed patterns. This study was conducted in the foothill forests of the Victorian Highlands, south-east Australia. Mixed-species eucalypt (genus Eucalyptus) forests dominate the vegetation of this region. Site selection was based on the occurrence of suitable riparian habitat interspersed within extensive, relatively undisturbed (i.e. no recent timber harvesting or fire events) forest mosaics. A series of 30 paired riparian and non-riparian sites were established among six stream systems in three forest areas (Bunyip State Park, Kinglake National Park and Marysville State Forest). Riparian sites were positioned alongside the stream and the non-riparian partner site was positioned on a facing slope at a distance of approximately 750 m. Bird surveys were carried out during 29 visits to each site between July 2001 and December 2002. Riparian sites were floristically distinct from non-riparian sites and had a more complex vegetation structure, including a mid-storey tree layer mostly absent from non-riparian sites, extensive fine litter and coarse woody debris, and dense ground-layer vegetation (e.g. sedges and ground ferns). The characteristic features of non-riparian habitats included a relatively dense canopy cover, a ground layer dominated by grasses and fine litter, and a high density of canopy-forming trees in the smaller size-classes. Riparian zones supported a significantly greater species richness, abundance and diversity of birds when compared to non-riparian habitats. The composition of bird assemblages differed significantly between riparian and non-riparian habitats, with riparian assemblages displaying a higher level of similarity among sites. The strongest contributors to observed dissimilarities between habitat types included species that occurred exclusively in either habitat type or species with large contrasts in abundance between habitat types. Much of the avifauna (36%) of the study area is composed of species that are common and widespread in south-east Australia (i.e. forest generalists). Riparian habitats were characterised by a suite of species more typical of wetter forest types in south-east Australia and many of these species had a restricted distribution in the forest mosaic. Some species (7%) occurred exclusively in riparian habitats (i.e. riparian selective species) while others (43%) were strongly linked to these habitats (i.e. riparian associated species). A smaller proportion of species occurred exclusively (2%) in non-riparian habitats (i.e. non-riparian selective species) or were strongly linked to these habitats (10%; i.e. non-riparian associated species). To examine the seasonal dynamics of assemblages, the variation through time in species richness, abundance and composition was compared between riparian and non-riparian sites. Riparian assemblages supported greater richness and abundance, and displayed less variation in these parameters, than non-riparian assemblages at all times. The species composition of riparian assemblages was distinct from non-riparian assemblages throughout the annual cycle. An influx of seasonal migrants elevated species richness and abundance in the forest landscape during spring and summer. The large-scale movement pattern (e.g. coastal migrant, inland migrant) adopted by migrating species was associated with their preference for riparian or non-riparian habitats in the landscape. Species which migrate north-south along the east coast of mainland Australia (i.e. coastal migrants) used riparian zones disproportionately; eight of eleven species were riparian associated species. Species which migrate north-south through inland Australia (i.e. inland migrants) were mostly associated with non-riparian habitats. The significant differences in the dynamics of community structure between riparian and non-riparian assemblages shows that there is a disproportionate use of riparian zones across the landscape and that they provide higher quality habitat for birds throughout the annual cycle. To examine the ecological mechanisms by which riparian assemblages are richer and support more individual birds, the number of ecological groups (foraging, nest-type and body mass groups) represented, and the species richness of these groups, was compared between riparian and non-riparian assemblages. The structurally complex vegetation and distinctive habitat features (e.g. aquatic environments, damp sheltered litter) provided in the riparian zone, resulted in the consistent addition of ecological groups to riparian assemblages (e.g. sheltered ground – invertebrates foraging group) compared with non-riparian assemblages. Greater species richness was accommodated in most foraging, nest-type and body mass groups in riparian than non-riparian assemblages. Riparian zones facilitated greater richness within ecological groups by providing conditions (i.e. more types of resources and greater abundance of resources) that promoted ecological segregation between ecologically similar species. For a set of commonly observed species, significant differences in their use of structural features, substrates and heights were registered between riparian and non-riparian habitats. The availability and dynamics of resources in riparian and non-riparian habitats were examined to determine if there is differential availability of particular resources, or in their temporal availability, throughout the annual cycle. Riparian zones supported more abundant and temporally reliable eucalypt flowering (i.e. nectar) than non-riparian habitats throughout the annual cycle. Riparian zones also supported an extensive loose bark resource (an important microhabitat for invertebrates) including more peeling bark and hanging bark throughout the year than at non-riparian sites. The productivity of eucalypts differed between habitat types, being higher in riparian zones at most times for all eucalypts combined, and for some species (e.g. Narrow-leaved Peppermint Eucalyptus radiata). Non-riparian habitats provided an abundant nectar resource (i.e. shrub flowering) at particular periods in the annual cycle. Birds showed clear relationships with the availability of specific food (i.e. nectar) and foraging resources (i.e. loose bark). The demonstration of a greater abundance of resources and higher primary productivity in riparian zones is consistent with the hypothesis that these linear strips that occupy only a small proportion of the landscape have a disproportionately high value for birds. Riparian zones in continuous eucalypt forest provide high quality habitats that contribute to the diversity of habitats and resources available to birds in the forest mosaic, with positive benefits for the landscape-level species pool. Despite riparian and non-riparian habitat supporting distinct assemblages of birds, strong linkages are maintained along the riparian-upslope gradient. Clearly, the maintenance of diverse and sustainable assemblages of birds in forest landscapes depends on complementary management of both riparian and non-riparian vegetation.

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The thesis explores an effective model for using the internet in a distance training program for secondary school teachers. The professional development program, the dissertation, titled The Virtual University: Professional development for teachers, was initiated based on aspects of telecommunication technology and the professional development for Thai school teachers. The question of this program was “How could information technology be used in developing an appropriate professional development model for Thai teachers?” Prior to the project, the four research studies were conducted to formulate the related base line information and supported framework for the program development. The four researches are: (1) Telecommunication Technology in Thai Schools, (2) The Role of University on Science Teachers Development, (3) Computer Education Curriculum for Student Teachers: Theory and Practice, and (4) Teachers’ Perceptions of the Academic Link Project Between Schools and Universities for Teacher Professional Development. The first research study provides the information about the necessary basic factors for change in Thai secondary schools and the new insights and understandings about change in Thai schooling. The major findings were the understandings about teachers’ need for professional development, the available support in Thai school for professional development, and the limitations of professional development of teachers. The second research study provides the information about the roles of university faculty on initiation and operation of science teacher development programs, science teaching and learning resources centers, science instructional media design and production services, science teaching clinics, and science teachers’ associations. The third research study provides the conceptual framework for both preservice and inservice curriculum development program for teacher development. The last research study provides a base of descriptive information about the perspectives of school teachers towards the academic link project between schools and universities and the partnership which can assist in its establishment. The findings of these four research tasks were used for the formation of the framework of the dissertation. The EDNET Project, an example of teachers’ professional development through the information technology based training, was developed and implemented with ten school teachers in Khon Kaen.

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There have been various changes to the manner in which early intervention services for children with disabilities have been provided in recent decades. One of the most significant paradigm shifts that has accoured pertains to a change in the level of family involvement in early intervention, so that families are now required to be equal partners with professionals in the service provision process. It is now policy in Victoria that early intervention services follow a family-centred model of practice. Services adopting this model aim to empower parents, so that they may have impact on their lives, and the lives of their family members, both during and beyond the years of direct service participation. Much of what is known about empowerment to date is based on theory, author opinion, and research that is largely survey-based. There has been little interview-based research, particulary involving parents of children with disabilities, as well as little Australian research conducted regarding empowerment. To the researcher's knowledge, there has been no interview-based research that specifically asked parents of children with disabilities about their perspectives on empowerment and disempowerment. Parents of children with disabilities are not invited to contribute their opinions in services and research. Empowerment is an individual concept and this research provided parents with an opportunity to express their views on this topic. Parent's perspectives on empowerment are vital for service providers who aim to follow the intervention model required by policy. This research, which was guided by the principles of ecological theory and critical theory, involved to individual semi-structured interviews with 37 Victorian families of children with disabilities. Twenty-one of these families had children currently participating in early intervention services, and 16 families had children of mid-primary school age, who had previously participated in early intervention experiences; the factors that they believe influence empowerment and disempowerment; and helpful and unhelpful experiences with early intervention staff and other people in their lives. Data were analysed primarily inductively, in the context of grounded theory. Responses from the two groups of parents were then compared, as were different emergent themes according to helpfulness and empowerment. The nature of enduring empowerment, one of the key objectives of early childhood intervention, was also considered. From the analysis of data, several themes emerged as influential in the empowerment process for both groups of parents including: information, education and knowledge; meeting and talking with other families of children with disabilities; decision-making and choice; having confidence; participation, involvement and input; meeting or addressing families' practical needs; and having a child with a disability. The results of this research provide valuable information for parents, professionals, agencies, organisations, and the wider community, regarding how families can be supported more effectively and how power can be more equitably balanced.

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Evidence exists to suggest that in Australia many environmental issues remain unresolved even though the community has apparently become more environmentally aware. Although universities have undertaken responsibility to educate future environmental professionals to address this concern, there are numerous tensions underpinning professional environmental education. This folio explores my perceptions of these tensions and their effect on my professional practice as an academic. I refer to this as the relationships among theories and practices experienced in my work. Four perspectives are taken in this research as I appraise professional environmental education. This Dissertation (Vol. 1) focuses on views informing my professional environmental education, inclusive of my own reflexivity. From interviews with students, academics, professionals and environmentalists, and other sources of information, I consider various tensions arising from what I regard as dehumanising social and political forces. The conventional elite and authoritative roles for universities and professionals dominate most participants' understanding of professional activities. Professional practices often endorse these conventions. Juxtaposed to this authoritative view of professional education, and prescribing a different interpretation for professional practice, is my theoretical position informed by criticality and a need to challenge the status quo. I suggest that Leopold's The Land Ethic is an exemplar of criticality and a suitable basis for examining professional environmental education. The Land Ethic is used as a foundation to my thesis because it encapsulates suitable arguments to examine ideologies supportive of my understanding of professional environmental education. My thesis investigates the nature of participants' (including my own) understanding of their land ethic or land ethics suggesting that interpretations of 'place' provide an emotional and ethical appreciation of the land. I suggest that 'place', as a culturally derived construct, is central to the concept of a land ethic or land ethics, and a characteristic of an environmental ethic or ethics. To incorporate these different perspectives into professional environmental education perhaps land could be viewed, not just as a 'client' as in Schön's (1983) reflective contract, but expanded so that professionals form ethical partnerships with the land, which implies a greater equity between roles and responsibilities. This perspective challenges elite interpretations of the roles for environmental professionals by asking them to be advocates for their land, and to work with the land. Searching for my own land ethic or land ethics has promoted a discourse that encompasses a language of possibility and opportunity. This language of possibility and opportunity stands in contrast to the constraining language of reproduction that has promoted stasis. My reflexivity, a holistic and ecological view that in this thesis is an expression of my searching for a land ethic or land ethics, has encouraged me to develop critical and ethical questions to challenge my professional environmental education practice. As such the process of theorising about my theory and practice has been personally transformative as it encourages my development as a 'critical person'. Elective 1 (Vol. 2 ) reviews public information promoting a selected range of Australian environmental courses. Analysis demonstrates environmental courses are mainly technocratic, promoting technical-scientific and vocational perspectives. This orientation, I consider, is aligned to an emerging corporate agenda as universities attempt to be more accountable to the government within a competitive market dominated by economic interests. Elective 2 (Vol. 2 ) considers the providers of professional environmental education where I explore a diversity of tensions undermining current academic life found in many Australian universities. I suggest that corporatisation and vocationalisation dominate university culture to such an extent that any examination of professional environmental education is prejudiced. Professional environmental education appears to be biased toward maintaining the status quo. My conclusion is that professional environmental education does not promote graduates as 'critical persons' (Barnett 1997), and this may affect graduates' understandings of the purpose and aspirations of environmental professionalism. I suggest that elite and technical understandings of professionalism may affect the professionals' ability to implement environmental policy. Australia has an admirable record of developing environmental policy. However, public concern about a lack of resolution for many environmental issues suggests that professionals may be struggling to successfully implement policy in any meaningful way. Such challenges for environmental professionals may be a result of a professional environmental education that does not engage graduates within ideas that professional practice may require community participation and collaboration as key themes. Elective 3 (Vol. 2) is a case study investigating the development of conservation policies by the Ballarat community. The case demonstrates how the dominant social paradigm informs community views about environmental issues emphasising a technical emphasis and hierarchical arrangements of power and authority between local government and the community. The community view appears to be that environmental action should be mainly individualistic and behaviourist, which I suggest may have resulted from a technical framework for environmental knowledge. The community view of environmental issues resonates with the dominant view promoted by professional environmental education in most universities. In conclusion, my thesis is a representation of my challenges to critically engage in possible relationships among theories, practices and circumstances in my workplace, with a view to addressing what I perceive as a 'gap' between my own theory and practice. The motivation for this critical examination is to question the purpose of my professional environmental education practice in relation to the challenges of my emergent environmental ideology. The difficulty of promoting my critical theorising in a traditional small science faculty, within a corporate university, with my scientific background, is acknowledged. Nevertheless, based on my own experiences, I recommend that academics involved in professional environmental education should be encouraged to explore relationships between their own theories and practices in their own professional settings. I suggest that the search for a land ethic or land ethics, and one's 'place' in the 'land', can be an effective platform for this process.

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Maternally derived yolk antibodies provide neonates with immune protection in early life at negligible cost to mothers. However, developmental effects on the neonate's future immunity are potentially costly and thus could limit yolk antibody deposition. The benefits to neonatal immunity must be balanced against costs, which may depend on neonate vulnerability to pathogens, developmental trajectories and the immunological strategies best suited to a species' pace of life. We measured yolk antibodies and life-history features of 23 species of small Neotropical birds and assessed the evidence for each of several hypotheses for life history and ecological effects on the evolution of yolk antibody levels. Developmental period and yolk antibodies are negatively related, which possibly reflect the importance of humoral immune priming through antigen exposure, and selection to avoid autoimmunity, in species with a slower pace of life. There is also a strong relationship between body size and yolk antibody concentration, suggesting that larger species are architecturally equipped to produce and transfer higher concentrations of antibodies. These results suggest that developmental effects of maternally derived antibodies, such as imprinting effects on B-cell diversity or autoimmune effects, are important and deserve more consideration in future research.

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Background: Smoking is the largest single cause of preventable death and disease in Australia. This study describes smoking prevalence and the characteristics of rural smokers to guide general practitioners in targeting particular groups.

Methods: Cross sectional surveys in the Greater Green Triangle region of southeast Australia using a random population sample (n=1563, participation rate 48.7%) aged 25–74 years. Smoking information was assessed by a self administered questionnaire.

Results: Complete smoking data were available for 1494 participants. Overall age adjusted current smoking prevalence was 14.9% (95% CI: 13.1–16.7). In both genders, current smoking prevalence decreased with age. Those aged 25–44 years were more likely to want to stop smoking and to have attempted cessation, but less likely to have received cessation advice than older smokers.

Discussion
: This study provides baseline smoking data for rural health monitoring and identifies intervention opportunities. General practice is suited to implement interventions for smoking prevention and cessation at every patient encounter, particularly in younger individuals.

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The purpose of this study was to assess farmers’ attitudes, as well as perceptions and knowledge that shape those attitudes, toward the ecological role of vertebrates inhabiting shaded-coffee farms. We also aimed to determine whether differences existed among two groups of farmers: one that had attended environmental education workshops, and one that had not. We conducted 36 oral interviews of farmers in the region of Cuetzalan, Mexico. All farmers were members of an important regional cooperative, Tosepan Titataniske. In general, farmers’ attitudes towards birds were positive. Snakes were perceived as useful but dangerous animals. Attitudes towards nonflying mammals were mostly indifferent. Bats were poorly understood and badly perceived. Seed dispersal was perceived as an important ecological function performed by animals. Pollination was also perceived as important, but to a lesser degree. Knowledge about ecological functions was high for seed dispersal, and low for pollination. We found a positive correlation between attendance of educational workshops and the presence of “environmentally-friendly” attitudes, perceptions, and knowledge. However, a cause-effect relationship could not be clearly established. We suggest that environmental education programs include the objective of increasing the knowledge of people about the ecological functions played by different groups of animals that live in agroecosystems. Particular efforts should be directed toward improving the way in which certain non-charismatic groups of animals, such as bats, are perceived.