title: Seagrass resilience to waterfowl grazing in a temperate estuary: A multi-site experimental study

authors: Dos Santos, Virginie

subjects: Cygnus atratus

abstract: In New Zealand, black swans have been observed to graze a moderate to large proportion of the biomass of intertidal seagrass (Zostera muelleri) meadows. To evaluate the resilience of seagrass meadows to swan grazing, we performed a grazing simulation experiment at four sites in a large temperate estuary (Tauranga Harbour). In late summer, when swan grazing pressure typically peaks, we established control (0% biomass removed), low grazing intensity (~ 40% biomass removed) and high grazing intensity (~ 100% biomass removed) plots (0.25 m2) to mimic the grazing scars created by black swans. For one year, percentage seagrass above-ground cover of plots and a wider area surrounding the plots (0.75 m2) was monitored monthly. Seagrass biomass and leaf size were measured at the start and end of the experiment. Results showed no significant grazing treatment effect on seagrass leaf size (length and width). The low grazing intensity treatment had no detectable effect on seagrass cover or biomass relative to controls. For the high grazing intensity plots at all sites seagrass cover was restored within 8 months but biomass was not fully restored (only 25–42% of controls) one year later. This suggests that it may take several years (2.4–4.0, assuming a constant recovery rate) for seagrass below-ground biomass and leaf layering to regenerate completely in the grazing scars created by swans.

text: Seagrass resilience to waterfowl grazing in a temperate estuary: A multi-site experimental study In New Zealand, black swans have been observed to graze a moderate to large proportion of the biomass of intertidal seagrass (Zostera muelleri) meadows. To evaluate the resilience of seagrass meadows to swan grazing, we performed a grazing simulation experiment at four sites in a large temperate estuary (Tauranga Harbour). In late summer, when swan grazing pressure typically peaks, we established control (0% biomass removed), low grazing intensity (~ 40% biomass removed) and high grazing intensity (~ 100% biomass removed) plots (0.25 m2) to mimic the grazing scars created by black swans. For one year, percentage seagrass above-ground cover of plots and a wider area surrounding the plots (0.75 m2) was monitored monthly. Seagrass biomass and leaf size were measured at the start and end of the experiment. Results showed no significant grazing treatment effect on seagrass leaf size (length and width). The low grazing intensity treatment had no detectable effect on seagrass cover or biomass relative to controls. For the high grazing intensity plots at all sites seagrass cover was restored within 8 months but biomass was not fully restored (only 25–42% of controls) one year later. This suggests that it may take several years (2.4–4.0, assuming a constant recovery rate) for seagrass below-ground biomass and leaf layering to regenerate completely in the grazing scars created by swans.

year: 2013

title: Molecular adaptations to psychrophily: the impact of ‘omic’ technologies

authors: Casanueva, Ana

subjects: molecular adaptations

abstract: The ability of cold-adapted microorganisms (generally referred to as psychrophiles) to survive is the result of molecular evolution and adaptations which, together, counteract the potentially deleterious effects of low kinetic energy environments and the freezing of water. These physiological adaptations are seen at many levels. Against a background of detailed comparative protein structural analyses, the recent surge of psychrophile proteome, genome, metagenome and transcriptome sequence data has triggered a series of sophisticated analyses of changes in global protein composition. These studies have revealed consistent and statistically robust changes in amino acid composition, interpreted as evolutionary mechanisms designed to destabilise protein structures, as well as identifying the presence of novel genes involved in cold adaptation.

text: Molecular adaptations to psychrophily: the impact of ‘omic’ technologies The ability of cold-adapted microorganisms (generally referred to as psychrophiles) to survive is the result of molecular evolution and adaptations which, together, counteract the potentially deleterious effects of low kinetic energy environments and the freezing of water. These physiological adaptations are seen at many levels. Against a background of detailed comparative protein structural analyses, the recent surge of psychrophile proteome, genome, metagenome and transcriptome sequence data has triggered a series of sophisticated analyses of changes in global protein composition. These studies have revealed consistent and statistically robust changes in amino acid composition, interpreted as evolutionary mechanisms designed to destabilise protein structures, as well as identifying the presence of novel genes involved in cold adaptation.

year: 2010

title: Puhi: Memories and experiences in their ceremonial role in traditional and contemporary Maori worlds

authors: Simpson, Ariana

subjects: psychology

abstract: According to early writers, Puhi are described as the treasured daughters of chiefs, were of high rank, endowed with aristocracy, and fiercely protected and respected by the tribe. They were renowned for their beauty, their courage and leadership. Although very little information and knowledge on the function and the role of Puhi is available, information has been sought from early and contemporary writings, tribal narratives, oral histories and memories and experiences of women in their ceremonial role as puhi in traditional and contemporary times. Of interest for this research is the value and belief system in which the role and function of Puhi has survived and exists today, given that in today’s society, Maori women and their children are the primary victims of domestic violence in Aotearoa. This research aims to identify and highlight the importance of kotiro in traditional and contemporary times and to provide a clearer understanding of Puhi by documenting and recording experiences, memories and early writings.

text: Puhi: Memories and experiences in their ceremonial role in traditional and contemporary Maori worlds According to early writers, Puhi are described as the treasured daughters of chiefs, were of high rank, endowed with aristocracy, and fiercely protected and respected by the tribe. They were renowned for their beauty, their courage and leadership. Although very little information and knowledge on the function and the role of Puhi is available, information has been sought from early and contemporary writings, tribal narratives, oral histories and memories and experiences of women in their ceremonial role as puhi in traditional and contemporary times. Of interest for this research is the value and belief system in which the role and function of Puhi has survived and exists today, given that in today’s society, Maori women and their children are the primary victims of domestic violence in Aotearoa. This research aims to identify and highlight the importance of kotiro in traditional and contemporary times and to provide a clearer understanding of Puhi by documenting and recording experiences, memories and early writings.

year: 2006