title: Examining Driving Risk And Lifestyle Factors Influencing Speed Preference In A Laboratory-Based Speed Choice Task

authors: O'Sullivan, Dominic

subjects: Speed

abstract: Vehicle crashes are one of the leading causes of severe injury or death in the world, and are accompanied by tremendous social and financial burdens. Excessive or inappropriate speed plays a major role in increasing the likelihood that a crash will occur, as well as elevating the severity of injury or damage. Young drivers are disproportionately over-represented in speed related crash involvement, and determining the factors contributing to young driver crashes is an important consideration. Both age and gender stand out as playing important roles in drivers crash likelihood, with the probability of being involved in a crash being significantly elevated for drivers aged under 25 years old. Young drivers are also prone to over-confidence in their driving skills, and this ‘poor calibration’ has been found to be a factor in crash involvement. Also, lack of impulse control could be a major factor related to speeding behaviour. Young drivers may have still developing executive functions of the frontal lobes, which might explain these age related factors of unsafe driving.   
One yet unexplored factor in determining the likelihood of crash involvement is the role of life satisfaction and well-being in driving behaviour. Low levels of life satisfaction have been found to be associated with risky, maladaptive, or disadvantageous behaviours. Given that younger people have high rates of depression and anxiety, this may implicate life satisfaction as an important and unexplored area of interest in driver psychology. In the current study, we looked to explore whether different levels of life satisfaction was related to the way drivers chose preferred speeds in a laboratory and video-based speed choice task. Additionally, measures of self-rated driver skills, past driving violations, as well as probability of future risky driving behaviour were used in order to predict speed choices in young driver. 
 It was found that while there was significant difference between gender groups, with the unexpected finding of female drivers choosing faster speeds, the life-satisfaction measures were not found to be significant in predicting speed choices. However, it was indeed observed that drivers who were classified as low in life satisfaction tended to choose faster speeds, but this needs to be replicated with a larger sample to increase the power of the statistics, possibly revealing a significant effect. The thesis discusses limitations of the current research as well as suggestions for further research.

text: Examining Driving Risk And Lifestyle Factors Influencing Speed Preference In A Laboratory-Based Speed Choice Task Vehicle crashes are one of the leading causes of severe injury or death in the world, and are accompanied by tremendous social and financial burdens. Excessive or inappropriate speed plays a major role in increasing the likelihood that a crash will occur, as well as elevating the severity of injury or damage. Young drivers are disproportionately over-represented in speed related crash involvement, and determining the factors contributing to young driver crashes is an important consideration. Both age and gender stand out as playing important roles in drivers crash likelihood, with the probability of being involved in a crash being significantly elevated for drivers aged under 25 years old. Young drivers are also prone to over-confidence in their driving skills, and this ‘poor calibration’ has been found to be a factor in crash involvement. Also, lack of impulse control could be a major factor related to speeding behaviour. Young drivers may have still developing executive functions of the frontal lobes, which might explain these age related factors of unsafe driving.   
One yet unexplored factor in determining the likelihood of crash involvement is the role of life satisfaction and well-being in driving behaviour. Low levels of life satisfaction have been found to be associated with risky, maladaptive, or disadvantageous behaviours. Given that younger people have high rates of depression and anxiety, this may implicate life satisfaction as an important and unexplored area of interest in driver psychology. In the current study, we looked to explore whether different levels of life satisfaction was related to the way drivers chose preferred speeds in a laboratory and video-based speed choice task. Additionally, measures of self-rated driver skills, past driving violations, as well as probability of future risky driving behaviour were used in order to predict speed choices in young driver. 
 It was found that while there was significant difference between gender groups, with the unexpected finding of female drivers choosing faster speeds, the life-satisfaction measures were not found to be significant in predicting speed choices. However, it was indeed observed that drivers who were classified as low in life satisfaction tended to choose faster speeds, but this needs to be replicated with a larger sample to increase the power of the statistics, possibly revealing a significant effect. The thesis discusses limitations of the current research as well as suggestions for further research.

year: 2016

title: Studies of source area hydrology under indigenous forest and pastoral agriculture in the Hapuakohe Range, North Island, New Zealand

authors: Petch, R.A.

abstract: This thesis describes a systematic study of hillslope runoff processes and stream flow processes from two forms of land use characteristic of the New Zealand steep land environment: indigenous forest (podocarp-hardwood association) and pastoral agriculture.

In humid temperate environments, hillslope runoff is now recognised to result from a variety of mechanisms, that are dynamic and spatially variable. In these environments, surface and subsurface hillslope runoff processes are dependent on the soil, topographic and vegetation characteristics of individual catchments. The terms ‘partial and variable source area models’ have been used to describe these concepts and flow processes.

The new concepts of hillslope runoff generation have important implications for the way in which land is managed to maintain desirable stream flow characteristics and stream water quality. However, this information has not been used widely as a basis for land management procedures in areas where conflicts of land and water use occur. This situation has occurred because most of the studies of source area hydrology have been qualitative and have not provided information suitable for use in applied management problems. Also, few comparative land use studies have been established since the new concepts of source area hydrology have been developed.

The main aim of this study was to clarify the processes of hillslope runoff under indigenous forest and pastoral agriculture, and to interpret the hydrologic implications of these two forms of land use on the basis of the new concepts of hillslope runoff. 

A comprehensive, integrated study of source area hydrology was established in a steepland catchment supporting the two vegetation types. Although the areas of forest and pasture vegetation were contiguous areas within a single catchment, each vegetation type was treated as a separate hydrologic entity and referred to as an individual catchment. Both ‘process’ scale experiments and some ‘catchment’ scale experiments were established to understand fully the processes of hillslope runoff and the relationships between hillslope flow processes and stream flow processes in the two land use catchments.

An experimental design was developed for this study based on the partial and variable concepts of source area hydrology. The experimental catchments were subdivided into three  geomorphically distinct sub-catchment units (riparian, midslope and spur regions) on the basis of a preliminary survey of the spatial distribution of soil moisture.

Data were collected on rainfall, stream flow, surface and subsurface runoff components and soil moisture, during weekly visits to the catchments over a two year period, July 1979 - July 1981. Quantitative estimates of the spatial variability of surface and subsurface hillslope runoff components were made in the sub-catchment units of each land use catchment. The processes of hillslope runoff were also examined within each sub-catchment unit. Additional studies of forest interception processes, soil permeability and other soil, topographic and vegetation characteristics were completed during this period.

The results of this study show that the hillslope runoff regimes are complex in both land use catchments. In each land use, hillslope runoff processes vary spatially and seasonally. The results also show that the differences in hillslope runoff processes are not consistent, either between the sub-catchment units of each land use catchment, or between similar sub-catchment units of both land use catchments. Despite the complexity of the hillslope runoff processes, the integrated stream flow responses from each land use catchment are less variable, and show the differences expected for the two vegetation types.

For most storm events, the spatial distribution of hillslope runoff conforms with the patterns described by the variable source area model of hillslope runoff. However, the mechanisms of hillslope runoff and the causes of the spatial distribution of these processes are not described well by this model. 

Infiltration-excess overland flow is generated above the mineral soil in each land use catchment, despite the intermittent, low intensity, rainfall. Infiltration-excess overland flow occurs because the catchment soils are considerably less permeable than in other catchments in similar environments. The spatial distribution of surface runoff is dependent on the spatial variability of soil permeability in each land use that is, in turn, determined by variations of soil moisture in space and time.

Subsurface discharges are also less important in determining the stream hydrograph from the two land use catchments studied, than reported in other studies of similar forms of land use. The catchment soils are so slowly permeable that large volumes of subsurface runoff do not reach the stream channel in time to contribute to storm runoff. 

An examination of stream flow processes and water balance data was completed to provide an analysis of the integrated runoff response from the two land use catchments. Compared with the forest, greater stream discharges occur from the pasture land use for all flow regimes. However, the time distribution of the storm runoff response is independent of vegetation type or antecedent catchment conditions. The principal differences in the water balance components from each land use catchment are caused by differences in interception losses: similar transpiration rates were observed for the two vegetation types.

Selective catchment management, of riparian areas in pasture catchments in the Hapuakohe Range, is suggested as a method of improving general stream flow characteristics from these areas, while the multiple use of the land and water resources is maintained. Estimates of the effectiveness of this management strategy are presented. However, the degree to which riparian re-afforestation causes a satisfactory change in stream flow characteristics, depends entirely on the objective of the land management practices proposed for a given catchment.

text: Studies of source area hydrology under indigenous forest and pastoral agriculture in the Hapuakohe Range, North Island, New Zealand This thesis describes a systematic study of hillslope runoff processes and stream flow processes from two forms of land use characteristic of the New Zealand steep land environment: indigenous forest (podocarp-hardwood association) and pastoral agriculture.

In humid temperate environments, hillslope runoff is now recognised to result from a variety of mechanisms, that are dynamic and spatially variable. In these environments, surface and subsurface hillslope runoff processes are dependent on the soil, topographic and vegetation characteristics of individual catchments. The terms ‘partial and variable source area models’ have been used to describe these concepts and flow processes.

The new concepts of hillslope runoff generation have important implications for the way in which land is managed to maintain desirable stream flow characteristics and stream water quality. However, this information has not been used widely as a basis for land management procedures in areas where conflicts of land and water use occur. This situation has occurred because most of the studies of source area hydrology have been qualitative and have not provided information suitable for use in applied management problems. Also, few comparative land use studies have been established since the new concepts of source area hydrology have been developed.

The main aim of this study was to clarify the processes of hillslope runoff under indigenous forest and pastoral agriculture, and to interpret the hydrologic implications of these two forms of land use on the basis of the new concepts of hillslope runoff. 

A comprehensive, integrated study of source area hydrology was established in a steepland catchment supporting the two vegetation types. Although the areas of forest and pasture vegetation were contiguous areas within a single catchment, each vegetation type was treated as a separate hydrologic entity and referred to as an individual catchment. Both ‘process’ scale experiments and some ‘catchment’ scale experiments were established to understand fully the processes of hillslope runoff and the relationships between hillslope flow processes and stream flow processes in the two land use catchments.

An experimental design was developed for this study based on the partial and variable concepts of source area hydrology. The experimental catchments were subdivided into three  geomorphically distinct sub-catchment units (riparian, midslope and spur regions) on the basis of a preliminary survey of the spatial distribution of soil moisture.

Data were collected on rainfall, stream flow, surface and subsurface runoff components and soil moisture, during weekly visits to the catchments over a two year period, July 1979 - July 1981. Quantitative estimates of the spatial variability of surface and subsurface hillslope runoff components were made in the sub-catchment units of each land use catchment. The processes of hillslope runoff were also examined within each sub-catchment unit. Additional studies of forest interception processes, soil permeability and other soil, topographic and vegetation characteristics were completed during this period.

The results of this study show that the hillslope runoff regimes are complex in both land use catchments. In each land use, hillslope runoff processes vary spatially and seasonally. The results also show that the differences in hillslope runoff processes are not consistent, either between the sub-catchment units of each land use catchment, or between similar sub-catchment units of both land use catchments. Despite the complexity of the hillslope runoff processes, the integrated stream flow responses from each land use catchment are less variable, and show the differences expected for the two vegetation types.

For most storm events, the spatial distribution of hillslope runoff conforms with the patterns described by the variable source area model of hillslope runoff. However, the mechanisms of hillslope runoff and the causes of the spatial distribution of these processes are not described well by this model. 

Infiltration-excess overland flow is generated above the mineral soil in each land use catchment, despite the intermittent, low intensity, rainfall. Infiltration-excess overland flow occurs because the catchment soils are considerably less permeable than in other catchments in similar environments. The spatial distribution of surface runoff is dependent on the spatial variability of soil permeability in each land use that is, in turn, determined by variations of soil moisture in space and time.

Subsurface discharges are also less important in determining the stream hydrograph from the two land use catchments studied, than reported in other studies of similar forms of land use. The catchment soils are so slowly permeable that large volumes of subsurface runoff do not reach the stream channel in time to contribute to storm runoff. 

An examination of stream flow processes and water balance data was completed to provide an analysis of the integrated runoff response from the two land use catchments. Compared with the forest, greater stream discharges occur from the pasture land use for all flow regimes. However, the time distribution of the storm runoff response is independent of vegetation type or antecedent catchment conditions. The principal differences in the water balance components from each land use catchment are caused by differences in interception losses: similar transpiration rates were observed for the two vegetation types.

Selective catchment management, of riparian areas in pasture catchments in the Hapuakohe Range, is suggested as a method of improving general stream flow characteristics from these areas, while the multiple use of the land and water resources is maintained. Estimates of the effectiveness of this management strategy are presented. However, the degree to which riparian re-afforestation causes a satisfactory change in stream flow characteristics, depends entirely on the objective of the land management practices proposed for a given catchment.

year: 1984

title: Different coloured tears: Dual cultural identity and Tangihanga – A directed study

authors: Edge, Kiri

subjects: bereavement

abstract: Although whānau/family that are configured by both Pākehā and Māori identities number significantly within New Zealand, there has been little or no attention paid to the ways in which these identities influence the bereavement processes that will inevitably impact upon the lives of these whānau/family. The present study explored the experiences of an individual, whose whānau/family included two life ways; Māori and Pākehā. Of specific focus was the ways in which these identities influenced his bereavement subsequent to the death of his beloved wife, who was of Māori descent. One elderly male Pākehā participant was interviewed, using an open-ended narrative approach. The interview was semi structured around five broad themes, but the focus was upon the participant’s experiences and his preference in expressing these. The data analysis utilised a thematic process, which allowed the participant’s experiences to determine the emergent themes. The results depicted the diversity of issues that may be raised for dual cultural whānau/family within bereavement processes. Two central themes are discussed in relation to intercultural conflict and the eventual resolution that was created. Decision making processes, cultural and language differences played significant roles within the conflict and exclusion experienced by the participant. Communication and compromise provided resolution to the prior conflicts experienced. This created positive and unexpected outcomes which resulted in increased understandings and the strengthening of links between the participant, his whānau/family and his wife’s marae.

text: Different coloured tears: Dual cultural identity and Tangihanga – A directed study Although whānau/family that are configured by both Pākehā and Māori identities number significantly within New Zealand, there has been little or no attention paid to the ways in which these identities influence the bereavement processes that will inevitably impact upon the lives of these whānau/family. The present study explored the experiences of an individual, whose whānau/family included two life ways; Māori and Pākehā. Of specific focus was the ways in which these identities influenced his bereavement subsequent to the death of his beloved wife, who was of Māori descent. One elderly male Pākehā participant was interviewed, using an open-ended narrative approach. The interview was semi structured around five broad themes, but the focus was upon the participant’s experiences and his preference in expressing these. The data analysis utilised a thematic process, which allowed the participant’s experiences to determine the emergent themes. The results depicted the diversity of issues that may be raised for dual cultural whānau/family within bereavement processes. Two central themes are discussed in relation to intercultural conflict and the eventual resolution that was created. Decision making processes, cultural and language differences played significant roles within the conflict and exclusion experienced by the participant. Communication and compromise provided resolution to the prior conflicts experienced. This created positive and unexpected outcomes which resulted in increased understandings and the strengthening of links between the participant, his whānau/family and his wife’s marae.

year: 2010-01