title: Pittosporum kirkii: Autecology of an endemic shrub epiphyte

authors: Myron, Kirsty Jane

subjects: Pittosporum kirkii

abstract: This research investigated the autecology of the New Zealand endemic shrub epiphyte Pittosporum kirkii (Pittosporaceae). Pittosporum kirkii most frequently displays an epiphytic lifestyle, perched amongst nest epiphytes in the canopies of emergent or canopy trees in old-growth forest. The main objective of this research was to enhance the understanding of Pittosporum kirkii, with a focus on ecological, morphological and physiological characteristics. 

Ecological characteristics were investigated in field surveys of five key Pittosporum kirkii populations that encompass its known latitudinal extent. Survey results showed that P. kirkii is late successional epiphyte commonly found in the inner crown of large canopy and emergent hosts amongst nest epiphytes, it has a short flowering season and shows clinal patterns in leaf length with increasing latitude. Pittosporum kirkii meets the definition of a facultative epiphyte as it grows in rupestral, terrestrial and epiphytic lifestyles. The most common host species for P. kirkii is Dacrydium cupressinum.

Flowering was concentrated between November and December and individuals in the populations examined were functionally dioecious with a preponderance of males; flower pollinators and seed dispersers are uncertain.

Field data and supplementary data sets (e.g. herbarium records) were combined to develop a predicted environmental distribution map. Pittosporum kirkii has an abrupt distribution with strong habitat preferences restricting it to the upper North Island, in upper lowland and lower montane old-growth forest ecosystems. High vapour pressure deficits (>0.39 kPa) and low annual rainfall (<1172 mm) restrict environmental distribution. 

Investigations into the physiological and morphological characteristics of Pittosporum kirkii were focussed on water relations because water availability is speculated to be the most limiting factor across all of the habitats that P. kirkii occupies. In a glasshouse experiment P. kirkii seedlings were subjected to three levels of desiccation stress alongside epiphytic congener P. cornifolium. In the context of international literature, the stress strategies of each species were identified from analysis of morphological adaptations and physiological responses. Pittosporum kirkii has small relative leaf area, thick coriaceous upper leaf cuticles, substantial hypodermal tissue, and under desiccation stress, exhibited rapid reductions in stomatal conductance and photosynthetic activity with stress (ceased function at mean pre-dawn water potentials of -0.8 MPa). This evidence aligns P. kirkii with a desiccation postponement strategy. In contrast P. cornifolium has thinner cuticle hypodermal tissue, larger relative leaf area and maintains photosynthetic function under greater stress (ceased function at mean pre-dawn water potentials of -1.7 MPa), and as a result, lost water potential faster than P. kirkii. Therefore P. cornifolium is concluded to align with a desiccation tolerance stress strategy. Both species recovered within 3 days after re-watering, an important response for the drought-prone epiphytic, terrestrial and rupestral environments that both species inhabit.

Under the current threat classification Pittosporum kirkii is listed as in decline and is considered to be a data poor species. The threats to this species are uncertain; although possum browsing and forest clearance have been proposed, all available evidence is anecdotal and circumstantial. The abundant presence of P. kirkii on possum-free Great Barrier Island suggests relief from possum browse but other browsers are also restricted. Regenerative failures were not evident in mainland or offshore island populations and possum herbivory was not detected in mainland populations, likely because numbers were controlled. However, there may be other factors that may be potentially causing the decline of P. kirkii which could be identified with further research into pollinators, seed dispersal and sexual expression.

Pittosporum kirkii then is a distinctive member of New Zealand’s small guild of endemic shrub epiphytes but overall has the narrowest distribution, narrowest environmental profile, greatest habitat specificity and is the least abundant.

To present the key findings of this research alongside existing information, one chapter is presented in the format of the New Zealand Journal of Botany Biological Flora Series.

text: Pittosporum kirkii: Autecology of an endemic shrub epiphyte This research investigated the autecology of the New Zealand endemic shrub epiphyte Pittosporum kirkii (Pittosporaceae). Pittosporum kirkii most frequently displays an epiphytic lifestyle, perched amongst nest epiphytes in the canopies of emergent or canopy trees in old-growth forest. The main objective of this research was to enhance the understanding of Pittosporum kirkii, with a focus on ecological, morphological and physiological characteristics. 

Ecological characteristics were investigated in field surveys of five key Pittosporum kirkii populations that encompass its known latitudinal extent. Survey results showed that P. kirkii is late successional epiphyte commonly found in the inner crown of large canopy and emergent hosts amongst nest epiphytes, it has a short flowering season and shows clinal patterns in leaf length with increasing latitude. Pittosporum kirkii meets the definition of a facultative epiphyte as it grows in rupestral, terrestrial and epiphytic lifestyles. The most common host species for P. kirkii is Dacrydium cupressinum.

Flowering was concentrated between November and December and individuals in the populations examined were functionally dioecious with a preponderance of males; flower pollinators and seed dispersers are uncertain.

Field data and supplementary data sets (e.g. herbarium records) were combined to develop a predicted environmental distribution map. Pittosporum kirkii has an abrupt distribution with strong habitat preferences restricting it to the upper North Island, in upper lowland and lower montane old-growth forest ecosystems. High vapour pressure deficits (>0.39 kPa) and low annual rainfall (<1172 mm) restrict environmental distribution. 

Investigations into the physiological and morphological characteristics of Pittosporum kirkii were focussed on water relations because water availability is speculated to be the most limiting factor across all of the habitats that P. kirkii occupies. In a glasshouse experiment P. kirkii seedlings were subjected to three levels of desiccation stress alongside epiphytic congener P. cornifolium. In the context of international literature, the stress strategies of each species were identified from analysis of morphological adaptations and physiological responses. Pittosporum kirkii has small relative leaf area, thick coriaceous upper leaf cuticles, substantial hypodermal tissue, and under desiccation stress, exhibited rapid reductions in stomatal conductance and photosynthetic activity with stress (ceased function at mean pre-dawn water potentials of -0.8 MPa). This evidence aligns P. kirkii with a desiccation postponement strategy. In contrast P. cornifolium has thinner cuticle hypodermal tissue, larger relative leaf area and maintains photosynthetic function under greater stress (ceased function at mean pre-dawn water potentials of -1.7 MPa), and as a result, lost water potential faster than P. kirkii. Therefore P. cornifolium is concluded to align with a desiccation tolerance stress strategy. Both species recovered within 3 days after re-watering, an important response for the drought-prone epiphytic, terrestrial and rupestral environments that both species inhabit.

Under the current threat classification Pittosporum kirkii is listed as in decline and is considered to be a data poor species. The threats to this species are uncertain; although possum browsing and forest clearance have been proposed, all available evidence is anecdotal and circumstantial. The abundant presence of P. kirkii on possum-free Great Barrier Island suggests relief from possum browse but other browsers are also restricted. Regenerative failures were not evident in mainland or offshore island populations and possum herbivory was not detected in mainland populations, likely because numbers were controlled. However, there may be other factors that may be potentially causing the decline of P. kirkii which could be identified with further research into pollinators, seed dispersal and sexual expression.

Pittosporum kirkii then is a distinctive member of New Zealand’s small guild of endemic shrub epiphytes but overall has the narrowest distribution, narrowest environmental profile, greatest habitat specificity and is the least abundant.

To present the key findings of this research alongside existing information, one chapter is presented in the format of the New Zealand Journal of Botany Biological Flora Series.

year: 2012

title: Catabolism of naphthalene and phenanthrene by Burkholderia sp. strain RP007

authors: Laurie, Andrew David

abstract: Burkholderia sp. strain RP007 was isolated for its ability to utilise phenanthrene as a sole source of carbon and energy. This strain was identified as a Burkholderia sp. by biochemical tests, fatty acid analysis, and nucleotide sequencing of the 16S rRNA gene. The ability of Burkholderia sp. strain RP007 to mineralise [9-¹⁴C]phenanthrene and [1-¹⁴C]naphthalene was confirmed.

A gene cluster (phn) which represents a new group of upper pathway genes for polycyclic aromatic hydrocarbon (PAH) degradation was cloned from Burkholderia sp. strain RP007. Nucleotide sequencing of an 11.5 kb HindIII fragment cloned from RP007 revealed the presence of nine open reading frames (ORFѕ). Escherichia coli carrying the recombinant phn genes was able to transform naphthalene to salicylic acid. The phn genes are significantly different in sequence and gene order from the previously described nah, ndo, pah and dox genes for PAH degradation. The phn locus encodes iron-sulfur protein α and β subunits of a PAH initial dioxygenase, but not the ferredoxin and reductase components. The dihydrodiol dehydrogenase of the RP007 pathway, PhnB, shows greater similarity to analogous dehydrogenases from described biphenyl pathways than to those characterised from naphthalene/phenanthrene pathways. Furthermore, the RP007 extradiol dioxygenase, PhnC, shows no similarity to other extradiol dioxygenases for naphthalene or biphenyl oxidation, but is a member of the recently proposed Class III extradiol dioxygenases. Upstream of the phn catabolic genes are two putative regulatory genes phnR and phnS. phnR is divergently transcribed with respect to the other genes and is similar to the σ⁵⁴-dependent family of positive transcriptional regulators. phnS is a LysR-type transcriptional activator. Expression experiments suggest the phn operon is under regulatory control which may involve PhnR and PhnS.

Two loci encoding aromatic meta cleavage pathways were also cloned from Burkholderia sp. strain RP007. The nucleotide sequence of the catechol 2,3-dioxygenase genes, and adjacent open reading frames, suggest these are meta pathways of different classes which specify catabolism of different aromatic substrates. One of these may be the lower pathway for phenanthrene and naphthalene degradation.

The presence of catabolic genes homologous to the phnAc gene of Burkholderia sp. strain RP007, relative to the archetypal nahAc gene of Pseudomonas putida G7, was screened for in both culturable and nonculturable microbial communities. Of 77 environmental isolates cultured for their ability to degrade naphthalene or phenanthrene, 28 showed homology to nahAc, whilst none of the strains possessed catabolic genes similar to phnAc. However, using phnAc-specific primers, PCR products homologous to phnAc were amplified from DNA extracts of eight hydrocarbon-contaminated soils, demonstrating the widespread distribution of this genotype. Analysis of these phnAc PCR products by nucleotide sequencing of selected cloned products revealed very high (98.5-100%) homology to the phnAc gene of RP007, suggesting the phn genotype is highly conserved. PCR products were also amplified from soil DNA using nahAc-specific primers, and sequencing of these products revealed a diversity similar to that amongst previously described nah-like genes.

text: Catabolism of naphthalene and phenanthrene by Burkholderia sp. strain RP007 Burkholderia sp. strain RP007 was isolated for its ability to utilise phenanthrene as a sole source of carbon and energy. This strain was identified as a Burkholderia sp. by biochemical tests, fatty acid analysis, and nucleotide sequencing of the 16S rRNA gene. The ability of Burkholderia sp. strain RP007 to mineralise [9-¹⁴C]phenanthrene and [1-¹⁴C]naphthalene was confirmed.

A gene cluster (phn) which represents a new group of upper pathway genes for polycyclic aromatic hydrocarbon (PAH) degradation was cloned from Burkholderia sp. strain RP007. Nucleotide sequencing of an 11.5 kb HindIII fragment cloned from RP007 revealed the presence of nine open reading frames (ORFѕ). Escherichia coli carrying the recombinant phn genes was able to transform naphthalene to salicylic acid. The phn genes are significantly different in sequence and gene order from the previously described nah, ndo, pah and dox genes for PAH degradation. The phn locus encodes iron-sulfur protein α and β subunits of a PAH initial dioxygenase, but not the ferredoxin and reductase components. The dihydrodiol dehydrogenase of the RP007 pathway, PhnB, shows greater similarity to analogous dehydrogenases from described biphenyl pathways than to those characterised from naphthalene/phenanthrene pathways. Furthermore, the RP007 extradiol dioxygenase, PhnC, shows no similarity to other extradiol dioxygenases for naphthalene or biphenyl oxidation, but is a member of the recently proposed Class III extradiol dioxygenases. Upstream of the phn catabolic genes are two putative regulatory genes phnR and phnS. phnR is divergently transcribed with respect to the other genes and is similar to the σ⁵⁴-dependent family of positive transcriptional regulators. phnS is a LysR-type transcriptional activator. Expression experiments suggest the phn operon is under regulatory control which may involve PhnR and PhnS.

Two loci encoding aromatic meta cleavage pathways were also cloned from Burkholderia sp. strain RP007. The nucleotide sequence of the catechol 2,3-dioxygenase genes, and adjacent open reading frames, suggest these are meta pathways of different classes which specify catabolism of different aromatic substrates. One of these may be the lower pathway for phenanthrene and naphthalene degradation.

The presence of catabolic genes homologous to the phnAc gene of Burkholderia sp. strain RP007, relative to the archetypal nahAc gene of Pseudomonas putida G7, was screened for in both culturable and nonculturable microbial communities. Of 77 environmental isolates cultured for their ability to degrade naphthalene or phenanthrene, 28 showed homology to nahAc, whilst none of the strains possessed catabolic genes similar to phnAc. However, using phnAc-specific primers, PCR products homologous to phnAc were amplified from DNA extracts of eight hydrocarbon-contaminated soils, demonstrating the widespread distribution of this genotype. Analysis of these phnAc PCR products by nucleotide sequencing of selected cloned products revealed very high (98.5-100%) homology to the phnAc gene of RP007, suggesting the phn genotype is highly conserved. PCR products were also amplified from soil DNA using nahAc-specific primers, and sequencing of these products revealed a diversity similar to that amongst previously described nah-like genes.

year: 1998

title: Manaakitia te paharakeke: an insight into the daily operational challenges facing Te Whakaruruhau

authors: Kurei, Anna

subjects: Women's refuge

abstract: This report is based on participant observations of the daily operations at Te Whakaruruhau, Hamilton. The observations represent the fieldwork element of an undergraduate paper contributing to the co-author, Anna Kurei’s Bachelor’s degree at the University of Waikato. Anna’s participation and observations over several weeks included attending meetings, shadowing Advocates, contributing (as appropriate) to operations and observing interactions between Advocates and the women in living in the service’s residential housing. 
Founded by Ruahine Albert and Ariana Simpson in 1986, Te Whakaruruhau Incorporated (Waikato women's refuge) was the first Māori women's refuge in Aotearoa. Since its inception, Te Whakaruruhau has been a Kaupapa driven service, with Māori cultural practices consciously employed throughout all its operations. Māori tikanga is fluid and adaptable by nature and can therefore meet the needs of people from multiple cultures and backgrounds. The current service has grown from humble beginnings in a four-bedroom state owned house providing emergency housing, to now include a twenty-four-hour crisis service, residential housing and a broadened community outreach programme. Staff numbers have increased from 7 to 36 paid staff and the twenty-fourhour crisis service has allowed the refuge to provide services for high risk cases that would otherwise be turned away. 
Funding is critical to the successful operation of the service. The refuge provides wrap-around services to meet clients’ needs and help them navigate through a maze of government and community services. The needs of women and families who have lived with domestic violence are deep-seated and complex. Achieving a stable, healthy, independent life is frequently a long-term process. Funding however, is not only limited, but is tied to expectations of achieving successful outcomes in the short-term. It was quickly evident during the fieldwork that Te Whakaruruhau is desperately under-resourced. In the year to June 2015 the Refuge provided services for 6575 cases, but had contracted funds for less than 1600. The consequences of such starkly inadequate resources are dire – for both clients and staff.
Advocates (case workers) are frequently exhausted as they try to assist women and children with high and complex needs with very little resources on a highly restricted budget. Many times, workers were observed relegating their own interests (including their own health and safety) in order to meet the demands and needs of their clients. Similarly, the successful rehabilitation of clients is jeopardised by restricted options, insufficient capacity in the system and at times even the simplest of requirements such as transport to essential services. We know that when women and children become free of violence they have better health, employment and education outcomes. These outcomes benefit not only themselves but their communities and the wider social and economic landscape. Higher levels of funding - with a longer term focus- would therefore ultimately reduce the costs of domestic violence overall. Further to this, Kaupapa-based services at Te Whakaruruhau offer a culturally meaningful response to the high representation of Maori women seeking assistance. Its success in the face of such high levels of under-resourcing suggests that expectations around funding also need to be altered.

text: Manaakitia te paharakeke: an insight into the daily operational challenges facing Te Whakaruruhau This report is based on participant observations of the daily operations at Te Whakaruruhau, Hamilton. The observations represent the fieldwork element of an undergraduate paper contributing to the co-author, Anna Kurei’s Bachelor’s degree at the University of Waikato. Anna’s participation and observations over several weeks included attending meetings, shadowing Advocates, contributing (as appropriate) to operations and observing interactions between Advocates and the women in living in the service’s residential housing. 
Founded by Ruahine Albert and Ariana Simpson in 1986, Te Whakaruruhau Incorporated (Waikato women's refuge) was the first Māori women's refuge in Aotearoa. Since its inception, Te Whakaruruhau has been a Kaupapa driven service, with Māori cultural practices consciously employed throughout all its operations. Māori tikanga is fluid and adaptable by nature and can therefore meet the needs of people from multiple cultures and backgrounds. The current service has grown from humble beginnings in a four-bedroom state owned house providing emergency housing, to now include a twenty-four-hour crisis service, residential housing and a broadened community outreach programme. Staff numbers have increased from 7 to 36 paid staff and the twenty-fourhour crisis service has allowed the refuge to provide services for high risk cases that would otherwise be turned away. 
Funding is critical to the successful operation of the service. The refuge provides wrap-around services to meet clients’ needs and help them navigate through a maze of government and community services. The needs of women and families who have lived with domestic violence are deep-seated and complex. Achieving a stable, healthy, independent life is frequently a long-term process. Funding however, is not only limited, but is tied to expectations of achieving successful outcomes in the short-term. It was quickly evident during the fieldwork that Te Whakaruruhau is desperately under-resourced. In the year to June 2015 the Refuge provided services for 6575 cases, but had contracted funds for less than 1600. The consequences of such starkly inadequate resources are dire – for both clients and staff.
Advocates (case workers) are frequently exhausted as they try to assist women and children with high and complex needs with very little resources on a highly restricted budget. Many times, workers were observed relegating their own interests (including their own health and safety) in order to meet the demands and needs of their clients. Similarly, the successful rehabilitation of clients is jeopardised by restricted options, insufficient capacity in the system and at times even the simplest of requirements such as transport to essential services. We know that when women and children become free of violence they have better health, employment and education outcomes. These outcomes benefit not only themselves but their communities and the wider social and economic landscape. Higher levels of funding - with a longer term focus- would therefore ultimately reduce the costs of domestic violence overall. Further to this, Kaupapa-based services at Te Whakaruruhau offer a culturally meaningful response to the high representation of Maori women seeking assistance. Its success in the face of such high levels of under-resourcing suggests that expectations around funding also need to be altered.

year: 2016