Browsing by Author "Palmer, Karen Thelma"

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    An evaluation of the ecology and riparian management of the south branch of the Whareroa Stream, Paekakariki : a thesis presented in partial fulfilment of the requirements for the degree of Master of Applied Science in Natural Resource Management at Massey University
    (Massey University, 2008) Palmer, Karen Thelma
    Whareroa Farm, Mackays Crossing, Paekakariki, was bought by the Department of Conservation in 2005. The goal was to effect the restoration of a corridor for flora and fauna from the Akatarawa Forest in the east to Queen Elizabeth Park and the sea in the west. The south branch of the Whareroa Stream, which arises as a series of tributaries from a ridge 272m above sea level, traverses Whareroa Farm and the adjacent Queen Elizabeth Park. It was thought likely that the stream had been severely affected ecologically during a century of cattle and sheep farming, though the degree to which the ecological degradation had occurred was unknown. Obvious deforestation and land use changes suggested that, in concert with many other New Zealand hill country farms, the ecological changes would be significant. To establish and quantify the degree of degradation, the Auckland Regional Council (ARC) Stream Environment Valuation (SEV) protocol was applied to the Whareroa Stream and its tributaries. Five sites were selected for valuation, varying from open pasture to bush covered and open parkland. The resulting SEV scores showed losses of ecological value ranging from 32% to 46% across the sites. The Macroinvertebrate Community Index (MCI) and the fish Index of Biological Integrity (IBI) were measured at each site. Results indicated that aquatic habitats were unable to sustain adequate assemblages at four of the five sites. The valuations of the riparian zones at each site used the River Environment Classification (REC) and Riparian Management Classification (RMC) protocols. The results indicated that current riparian characteristics showed poor to absent effective riparian zones from the headwaters to the sea at all sites. Riparian zones are pivotal to the provision of stream ecological integrity and are responsible for maintaining the longitudinal, lateral and vertical connectivity between a stream, its network and its surrounding land. The loss of in-stream organic matter from lack of riparian vegetation together with the loss of effective temperature control from lack of shade, impacts negatively on the habitats for macroinvertebrates and fish. This was highlighted in the Whareroa Stream network. While the SEV and RMC evaluations showed that, with best practice management plans, there was great potential for improvement of the Whareroa Stream ecology, any riparian restoration would require sympathetic and improved fencing, withdrawal of stock from stream access and the retirement of headwater land from pastoral use. The loss of ecological integrity that occurs as a result of prolonged land use changes from forest to agriculture is well illustrated by the situation in the south branch of the Whareroa Stream and its tributaries.
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    Sustainable ecological systems and urban development in New Zealand : a wetlands case study : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Ecology at Massey University, New Zealand
    (Massey University, 2013) Palmer, Karen Thelma
    The destiny of urban wetlands lies largely in the hands of the urban planners. The results of this study suggest that planners are underestimating the importance of the urban wetland with irreversible consequences. The ecological integrity of natural systems like wetlands is inevitably compromised when they occur in urban environments. The Resource Management Act 1991 altered the approach to urban development from being entirely anthropocentric to one of consideration of the environment in which such developments were planned. Supposedly, adherence to the Act has resulted in a more focused approach to environmental outcomes in district and regional plans. However, this research into the effects of urban development on urban wetland riparian areas identifies a lack of appreciation of their structure and function. Eight palustrine wetlands were assessed for health and riparian function. They comprised two non-urban wetlands that provided the best-available ecological data on wetland health and six urban wetlands. Ecological indicators and urbanisation data were incorporated into a multi-metric model (named the Urban Wetland Health Index) to evaluate the biological health of urban wetlands. A key finding of this research is that the urban wetlands have poor ecological health and functioning indicated by excessive nutrients and algal blooms. Other key findings included the inadequate structure and function of the wetland riparian areas; the loss of riparian habitat associated with a lack of indigenous vegetation; the minimal cultural values given to the urban wetlands; and the negative impacts of urban imperviousness and inadequate stormwater infrastructure on wetland health. Notably, older residential areas that had poor stormwater connections to appropriate drainage also had the least healthy urban wetlands. The role of stormwater runoff in compromising the health of the urban wetlands was not addressed in the 2010 Kapiti Coast District Plan Review documents regarding Landscape and Biodiversity. These documents guide the development of the ‘second generation’ district plan. The Urban Wetland Health Index was found to be robust and reliable with this research. It was designed to address a gap in the tools available to planners, ecologists and other professionals seeking to assess the impacts of urban development on urban wetland ecosystem health. This Index is an important tool for use by councils in reviewing their district plans and undertaking plan changes. The incorporation of ecosystem services science into their policies and plans, and the understanding of the value of urban wetland ecosystem services, is needed to foster urban sustainability.