title: Lake Rotokawau: Water quality and sediment study

authors: Pearson, Lisa Kyle

abstract: Lake Rotokawau is a small (0.52 km2), deep (74 m), oligotrophic lake in the Rotorua Lakes District, located approximately 4.1 km east of Lake Rotorua. The lake is privately owned and managed by the local iwi, Ngati Rangiteaorere. During a site visit carried out on the 25 July 2010, surface and bottom water samples and a sediment core were collected, together with a water column profile (CTD) of temperature, dissolved oxygen, fluorescence, conductivity and depth. The CTD cast showed an anoxic hypolimnion and that the lake likely had not mixed during at the time of sampling, in mid-winter. This observation is highly unusual amongst the Te Arawa lakes and suggests that the lake may remain stratified for multiple years. The lack of mixing could be due to several factors including: presence of higher-salinity bottom waters, high water depth to area ratio, and sheltered aspect. The sediment core collected in the central basin revealed the presence of Ruapehu ash (1995-6 eruption) preserved in the upper 5 cm of the sediment record and the Tarawera Tephra (1886 eruption) located at 13 cm below the sediment water interface. The Ruapehu Ash layer is not preserved in sediment from any other Rotorua lakes and has likely been preserved due to the lack of seasonal mixing. The sediment and pore water chemistry are similar to that of the other lakes in the Rotorua region but however multiple sediment cores are necessary to fully assess variability across the whole lake area.
It is recommended that a routine monitoring programme be established so that any improvement or degradation in water quality can be detected and the mixing frequency of the lake determined. The water quality monitoring should include water column profiles of temperature, dissolved oxygen, fluorescence, conductivity and depth, nutrient analysis (ammonium, nitrate, nitrite, phosphate, silicon, total nitrogen and total phosphorus) of surface and bottom waters and water clarity readings (e.g. Secchi disk and light attenuation). Our observations point to the highly unusual nature of Lake Rotokawau in terms of mixing status and indicate a strong need to preserve significant biological and landscape features of this lake which has not been subject to problems with invasive species that characterise several other lakes in this region.

text: Lake Rotokawau: Water quality and sediment study Lake Rotokawau is a small (0.52 km2), deep (74 m), oligotrophic lake in the Rotorua Lakes District, located approximately 4.1 km east of Lake Rotorua. The lake is privately owned and managed by the local iwi, Ngati Rangiteaorere. During a site visit carried out on the 25 July 2010, surface and bottom water samples and a sediment core were collected, together with a water column profile (CTD) of temperature, dissolved oxygen, fluorescence, conductivity and depth. The CTD cast showed an anoxic hypolimnion and that the lake likely had not mixed during at the time of sampling, in mid-winter. This observation is highly unusual amongst the Te Arawa lakes and suggests that the lake may remain stratified for multiple years. The lack of mixing could be due to several factors including: presence of higher-salinity bottom waters, high water depth to area ratio, and sheltered aspect. The sediment core collected in the central basin revealed the presence of Ruapehu ash (1995-6 eruption) preserved in the upper 5 cm of the sediment record and the Tarawera Tephra (1886 eruption) located at 13 cm below the sediment water interface. The Ruapehu Ash layer is not preserved in sediment from any other Rotorua lakes and has likely been preserved due to the lack of seasonal mixing. The sediment and pore water chemistry are similar to that of the other lakes in the Rotorua region but however multiple sediment cores are necessary to fully assess variability across the whole lake area.
It is recommended that a routine monitoring programme be established so that any improvement or degradation in water quality can be detected and the mixing frequency of the lake determined. The water quality monitoring should include water column profiles of temperature, dissolved oxygen, fluorescence, conductivity and depth, nutrient analysis (ammonium, nitrate, nitrite, phosphate, silicon, total nitrogen and total phosphorus) of surface and bottom waters and water clarity readings (e.g. Secchi disk and light attenuation). Our observations point to the highly unusual nature of Lake Rotokawau in terms of mixing status and indicate a strong need to preserve significant biological and landscape features of this lake which has not been subject to problems with invasive species that characterise several other lakes in this region.

year: 2011-07

title: A cultural encounter through volunteer tourism: Towards the ideals of sustainable tourism?

authors: McIntosh, Alison J.

subjects: cultural tourism

abstract: International volunteering is increasingly recognised as a form of alternative tourism. However, the nature of the ‘alternative’ experience gained, and the ensuing narrative between host and volunteer, remains under-explored in published research, especially in volunteer tourism research within a cultural context in a developed nation. This paper examines the nexus between volunteer tourism and cultural tourism in the search for alternative and sustainable experiences through tourism. Qualitative research using in-depth interviews, diaries and participant observation was conducted to examine the pre-, during and post-trip experiences of 12 Australian visitors undertaking organised volunteer activities in an indigenous Maori community in the North Island of New Zealand during January 2005. Members of the indigenous Maori community were also interviewed to provide an important host perspective. Findings suggest that the nature of the interaction and cultural experiences gained were perceived as mutually beneficial and seemingly different from those gained from traditional cultural products. In particular, the volunteers experienced an alternative Maori cultural product and engaged in a different narrative with their Maori hosts through their volunteer work, one rich in authentic cultural content, genuine and reflective of modern Maori life in New Zealand society.

text: A cultural encounter through volunteer tourism: Towards the ideals of sustainable tourism? International volunteering is increasingly recognised as a form of alternative tourism. However, the nature of the ‘alternative’ experience gained, and the ensuing narrative between host and volunteer, remains under-explored in published research, especially in volunteer tourism research within a cultural context in a developed nation. This paper examines the nexus between volunteer tourism and cultural tourism in the search for alternative and sustainable experiences through tourism. Qualitative research using in-depth interviews, diaries and participant observation was conducted to examine the pre-, during and post-trip experiences of 12 Australian visitors undertaking organised volunteer activities in an indigenous Maori community in the North Island of New Zealand during January 2005. Members of the indigenous Maori community were also interviewed to provide an important host perspective. Findings suggest that the nature of the interaction and cultural experiences gained were perceived as mutually beneficial and seemingly different from those gained from traditional cultural products. In particular, the volunteers experienced an alternative Maori cultural product and engaged in a different narrative with their Maori hosts through their volunteer work, one rich in authentic cultural content, genuine and reflective of modern Maori life in New Zealand society.

year: 2007

title: An analysis of U-Value as a measure of variability

authors: Kong, Xiuyuan

subjects: Behavioral variability

abstract: The variability in behavior has frequently been assessed using a measure known as the U-value. Of concern in this article were the limits and constraints on U-value as a measure of variability. The relation between the U-value and aspects of variability was examined using three sets of simulated data. Our analysis demonstrates that the U-value as a measure of variability on its own fails to capture repetitive patterns in the sequence of responding. The U-value was shown to reflect the evenness of the distributions of responses across the categories/options used; however, when the number of categories actually used by the participant differed from the total number available, the relation between U-values and the number of categories allocated with responses was shown to be nonlinear. It was also shown that the same value of U can represent different levels of evenness in response distributions over categories, depending on the number of categories/options actually used. These constraints and limitations are discussed in relation to how researchers might report on behavioral variability.

text: An analysis of U-Value as a measure of variability The variability in behavior has frequently been assessed using a measure known as the U-value. Of concern in this article were the limits and constraints on U-value as a measure of variability. The relation between the U-value and aspects of variability was examined using three sets of simulated data. Our analysis demonstrates that the U-value as a measure of variability on its own fails to capture repetitive patterns in the sequence of responding. The U-value was shown to reflect the evenness of the distributions of responses across the categories/options used; however, when the number of categories actually used by the participant differed from the total number available, the relation between U-values and the number of categories allocated with responses was shown to be nonlinear. It was also shown that the same value of U can represent different levels of evenness in response distributions over categories, depending on the number of categories/options actually used. These constraints and limitations are discussed in relation to how researchers might report on behavioral variability.

year: 2017