title: Enhanced spatial pyramid matching using log-polar-based image subdivision and representation

authors: Zhang, Edmond Yiwen

subjects: object categorization

abstract: This paper presents a new model for capturing spatial information for object categorization with bag-of-words (BOW). BOW models have recently become popular for the task of object recognition, owing to their good performance and simplicity. Much work has been proposed over the years to improve the BOW model, where the Spatial Pyramid Matching (SPM) technique is the most notable. We propose a new method to exploit spatial relationships between image features, based on binned log-polar grids. Our model works by partitioning the image into grids of different scales and orientations and computing histogram of local features within each grid. Experimental results show that our approach improves the results on three diverse datasets over the SPM technique.

text: Enhanced spatial pyramid matching using log-polar-based image subdivision and representation This paper presents a new model for capturing spatial information for object categorization with bag-of-words (BOW). BOW models have recently become popular for the task of object recognition, owing to their good performance and simplicity. Much work has been proposed over the years to improve the BOW model, where the Spatial Pyramid Matching (SPM) technique is the most notable. We propose a new method to exploit spatial relationships between image features, based on binned log-polar grids. Our model works by partitioning the image into grids of different scales and orientations and computing histogram of local features within each grid. Experimental results show that our approach improves the results on three diverse datasets over the SPM technique.

year: 2010

title: The biogeography and trophic roles of coastal marine sponges (Porifera) from the west coast of the North Island, New Zealand: Influences of catchments.

authors: Mc Cormack, Samuel Patrick

subjects: Ecology

abstract: Anthropogenic activities are degrading coastal marine ecosystems globally. While the ecological and biodiversity implications of some of these impacts are well understood, for others there is a need for a greater understanding of the effects of these activities on vulnerable sedentary species. For researchers to pragmatically assess impacts on cryptic sponge species in highly productive reef systems, taxonomic assignment of these taxa is essential. With regards to the sponge fauna of Aotearoa, New Zealand, identification of sponge species is crucial for two main reasons. Firstly, these species significantly contribute to the productivity of inshore coastal reef ecosystems. Secondly, the existing literature of New Zealand’s sponge species has scarcities in species characterisation and identification for inshore sponge fauna. 
The Taranaki region is arguably foremost for consideration, as the coast would likely reflect any shifts in trans-Tasman current systems, and this region has a highly exposed geomorphology making it logistically difficult to conduct dive surveys. Furthermore, little is currently known about shallow water biogeography from this region. 
Focusing on temperate rocky reefs in the Taranaki Region of New Zealand, this thesis investigates the biogeography of sponge assemblages across broad spatial scales (hundreds of kms). It examines ecological processes, linked to trophic cascades to further our understanding of factors affecting the distribution and abundance of sponge communities at smaller spatial scales (tens of kms), with particular focus on the effects of land derived catchment discharges. 
	A combination of Linnean taxonomic classification and operational taxonomic units (OTUs) were used to identify sponge species and highlight locations with unique assemblages of taxa at regional scales. To achieve this a program of taxonomic revision was required, including the redescription of a collection of common sponge species Aaptos globosa, Acanthoclada prostrata, Biemna rufescens, Halichondria (Halichondria) moorei, and Stylissa haurakii. These results progress the modern requirements of these species description from those described in early New Zealand literature that lacked adequate and detailed descriptions and in situ images. 
As a precursor to the Taranaki ecological survey, a revision of sponge species from the Bay of Plenty was conducted. This study examined the family Dysideiidae and describes two novel sponge species (Dysidea tuapokere and Dysidea teawanui), from Tauranga Harbour, in the Bay of Plenty, and validated five species within New Zealand’s Exclusive Economic Zone, Dysidea cristagalli, D. hirciniformis, D. navicularis, D. ramsayi, D. spiculivora. Dysidea fragilis is now considered to be invalid, and D. elegans is considered unrecognisable. Further taxonomic assignment of Taranaki sponge fauna is required and is ongoing. The set of qualitative, but validated data now provides a baseline survey of spatial heterogeneity in terms of the distribution of sponge taxa across the Taranaki and central west coast North Island region. Biogeographic data showed that the geographic range of sponge species is highly patchy and supports the hypothesis that species assemblages at the Pariokariwa Reef (now part of the Parininihi Marine Reserve) are highly unique. Results from this investigation provide a baseline species diversity estimate within Taranaki and reveal Waitara reefs as biologically significant areas with the second largest number of unique sponge species out of all six locations surveyed. These findings have important implications for developing conservation strategies for marine fauna in Taranaki, highlighting locations of significant biological diversity, abundance, and uniqueness. Potential drivers for this biogeographic patchiness are addressed in subsequent sections of the research program. 
	Environmental factors influencing the distribution and abundance of marine sponges as described around the Taranaki region (Waitara reefs, Waiwhakaiho reefs, and Hangatahua Reef) over a three-year period were examined. There was a greater diversity and abundance of sponges at rocky reef stations that were in closer proximity to river mouths. This provides evidence that terrestrially derived organic matter from rivers may be supporting a greater assemblage and biomass of marine taxa on coastal rocky reefs, despite the increased sediment input from some of the catchments examined. The size of sponges in terms of volume were greater at coastal stations positioned next to rivers with a relatively large coverage of indigenous forests as opposed to reef systems adjacent to modified and urbanized catchments. An examination of the effects of several physico-chemical factors including turbidity, total phosphorus, total nitrogen, and Escherichia coli presence (an indicator of human and agricultural inputs), revealed that sponges appear to be resilient to certain degrees of exposure to these variables. There appears to be a negative correlation between effects of turbidity and nutrient level on sponges generally, with high levels of turbidity associated with decline in sponge characterised reef habitat. In contrast, some sponge species appear to thrive in turbid conditions that have high levels of nutrients in a form that they can profit from metabolically. Therefore, the quality of the catchment system can directly influence the quality of the nearshore benthic sponge assemblage. 
	Finally, the critical role of marine sponges in processing terrestrially derived carbon was investigated by examining the proportional contribution of food from various sources to the diet of sponges on temperate rocky reefs. Our isotope analysis revealed that marine food sources including coastal seston (>1.2–400 µm), coastal GFX (combined fine and coarse glass fibre filter samples >0.7–1.2 µm), and coastal bacteria (>0.2–0.7 µm) contributed the largest proportion to the diet of coastal sponges at 60–73% across our three stations. This was followed by a relatively large proportion of terrestrially derived food sources including freshwater seston (>1.2–400 µm), freshwater GFX (>0.7–1.2 µm), and freshwater bacteria (>0.2–0.7 µm) at 27–40%. Sponges are therefore argued to play significant roles in linking terrestrial and marine food webs, and associated carbon cycles, via recycling terrestrially derived carbon and nitrogen. Combining our estimated C retention rate with the isotopically-determined contribution of foods from terrestrial sources to the diet of coastal sponges (27–40%), suggests that sponge meadows may retain approximately 117–173 kg of terrestrially-derived C km−2 day
	In summary, the biogeographic distribution of sponge fauna that characterise nearshore reef environments around the Taranaki region has been described at large and small scales. This provides a baseline for future surveillance of nearshore ecological condition over ensuing years. This study highlights the importance of undertaking taxonomic precursor studies of regional sponge fauna to allow researchers to gain the taxonomic expertise to conductor wider scale ecological studies of this diverse phylum. The distribution of assemblages in Taranaki is particularly patchy with several highly unique communities being identified. These findings are important to the management of sponge fauna and the systems that support them. Land-based activities and ground cover and use are having direct effects on coastal reef communities, as seen in the distribution, abundance, and sizes of sponge species over large-scale environmental gradients. An important role of sponges in processing terrestrial derived carbon has been identified. The implications of this are that sponges are ingesting terrestrially derived organic matter on temperate reefs and potentially turning it into sources of food in the form of biomass, and cell shedding. This study shows that rivers and their derived food sources are important for coastal sponge communities. A unique assemblage of sponges was found close to a catchment system that discharges large quantities of sediment from significantly degraded hinterland suggesting that some taxonomic groups can thrive in areas where other species may struggle hence, species specific studies of how certain taxa adapt to multiple environmental stressors is suggested. Future studies should endeavour to further this research and expand our current understanding of sponge fauna as they constitute useful sentinel organisms.

text: The biogeography and trophic roles of coastal marine sponges (Porifera) from the west coast of the North Island, New Zealand: Influences of catchments. Anthropogenic activities are degrading coastal marine ecosystems globally. While the ecological and biodiversity implications of some of these impacts are well understood, for others there is a need for a greater understanding of the effects of these activities on vulnerable sedentary species. For researchers to pragmatically assess impacts on cryptic sponge species in highly productive reef systems, taxonomic assignment of these taxa is essential. With regards to the sponge fauna of Aotearoa, New Zealand, identification of sponge species is crucial for two main reasons. Firstly, these species significantly contribute to the productivity of inshore coastal reef ecosystems. Secondly, the existing literature of New Zealand’s sponge species has scarcities in species characterisation and identification for inshore sponge fauna. 
The Taranaki region is arguably foremost for consideration, as the coast would likely reflect any shifts in trans-Tasman current systems, and this region has a highly exposed geomorphology making it logistically difficult to conduct dive surveys. Furthermore, little is currently known about shallow water biogeography from this region. 
Focusing on temperate rocky reefs in the Taranaki Region of New Zealand, this thesis investigates the biogeography of sponge assemblages across broad spatial scales (hundreds of kms). It examines ecological processes, linked to trophic cascades to further our understanding of factors affecting the distribution and abundance of sponge communities at smaller spatial scales (tens of kms), with particular focus on the effects of land derived catchment discharges. 
	A combination of Linnean taxonomic classification and operational taxonomic units (OTUs) were used to identify sponge species and highlight locations with unique assemblages of taxa at regional scales. To achieve this a program of taxonomic revision was required, including the redescription of a collection of common sponge species Aaptos globosa, Acanthoclada prostrata, Biemna rufescens, Halichondria (Halichondria) moorei, and Stylissa haurakii. These results progress the modern requirements of these species description from those described in early New Zealand literature that lacked adequate and detailed descriptions and in situ images. 
As a precursor to the Taranaki ecological survey, a revision of sponge species from the Bay of Plenty was conducted. This study examined the family Dysideiidae and describes two novel sponge species (Dysidea tuapokere and Dysidea teawanui), from Tauranga Harbour, in the Bay of Plenty, and validated five species within New Zealand’s Exclusive Economic Zone, Dysidea cristagalli, D. hirciniformis, D. navicularis, D. ramsayi, D. spiculivora. Dysidea fragilis is now considered to be invalid, and D. elegans is considered unrecognisable. Further taxonomic assignment of Taranaki sponge fauna is required and is ongoing. The set of qualitative, but validated data now provides a baseline survey of spatial heterogeneity in terms of the distribution of sponge taxa across the Taranaki and central west coast North Island region. Biogeographic data showed that the geographic range of sponge species is highly patchy and supports the hypothesis that species assemblages at the Pariokariwa Reef (now part of the Parininihi Marine Reserve) are highly unique. Results from this investigation provide a baseline species diversity estimate within Taranaki and reveal Waitara reefs as biologically significant areas with the second largest number of unique sponge species out of all six locations surveyed. These findings have important implications for developing conservation strategies for marine fauna in Taranaki, highlighting locations of significant biological diversity, abundance, and uniqueness. Potential drivers for this biogeographic patchiness are addressed in subsequent sections of the research program. 
	Environmental factors influencing the distribution and abundance of marine sponges as described around the Taranaki region (Waitara reefs, Waiwhakaiho reefs, and Hangatahua Reef) over a three-year period were examined. There was a greater diversity and abundance of sponges at rocky reef stations that were in closer proximity to river mouths. This provides evidence that terrestrially derived organic matter from rivers may be supporting a greater assemblage and biomass of marine taxa on coastal rocky reefs, despite the increased sediment input from some of the catchments examined. The size of sponges in terms of volume were greater at coastal stations positioned next to rivers with a relatively large coverage of indigenous forests as opposed to reef systems adjacent to modified and urbanized catchments. An examination of the effects of several physico-chemical factors including turbidity, total phosphorus, total nitrogen, and Escherichia coli presence (an indicator of human and agricultural inputs), revealed that sponges appear to be resilient to certain degrees of exposure to these variables. There appears to be a negative correlation between effects of turbidity and nutrient level on sponges generally, with high levels of turbidity associated with decline in sponge characterised reef habitat. In contrast, some sponge species appear to thrive in turbid conditions that have high levels of nutrients in a form that they can profit from metabolically. Therefore, the quality of the catchment system can directly influence the quality of the nearshore benthic sponge assemblage. 
	Finally, the critical role of marine sponges in processing terrestrially derived carbon was investigated by examining the proportional contribution of food from various sources to the diet of sponges on temperate rocky reefs. Our isotope analysis revealed that marine food sources including coastal seston (>1.2–400 µm), coastal GFX (combined fine and coarse glass fibre filter samples >0.7–1.2 µm), and coastal bacteria (>0.2–0.7 µm) contributed the largest proportion to the diet of coastal sponges at 60–73% across our three stations. This was followed by a relatively large proportion of terrestrially derived food sources including freshwater seston (>1.2–400 µm), freshwater GFX (>0.7–1.2 µm), and freshwater bacteria (>0.2–0.7 µm) at 27–40%. Sponges are therefore argued to play significant roles in linking terrestrial and marine food webs, and associated carbon cycles, via recycling terrestrially derived carbon and nitrogen. Combining our estimated C retention rate with the isotopically-determined contribution of foods from terrestrial sources to the diet of coastal sponges (27–40%), suggests that sponge meadows may retain approximately 117–173 kg of terrestrially-derived C km−2 day
	In summary, the biogeographic distribution of sponge fauna that characterise nearshore reef environments around the Taranaki region has been described at large and small scales. This provides a baseline for future surveillance of nearshore ecological condition over ensuing years. This study highlights the importance of undertaking taxonomic precursor studies of regional sponge fauna to allow researchers to gain the taxonomic expertise to conductor wider scale ecological studies of this diverse phylum. The distribution of assemblages in Taranaki is particularly patchy with several highly unique communities being identified. These findings are important to the management of sponge fauna and the systems that support them. Land-based activities and ground cover and use are having direct effects on coastal reef communities, as seen in the distribution, abundance, and sizes of sponge species over large-scale environmental gradients. An important role of sponges in processing terrestrial derived carbon has been identified. The implications of this are that sponges are ingesting terrestrially derived organic matter on temperate reefs and potentially turning it into sources of food in the form of biomass, and cell shedding. This study shows that rivers and their derived food sources are important for coastal sponge communities. A unique assemblage of sponges was found close to a catchment system that discharges large quantities of sediment from significantly degraded hinterland suggesting that some taxonomic groups can thrive in areas where other species may struggle hence, species specific studies of how certain taxa adapt to multiple environmental stressors is suggested. Future studies should endeavour to further this research and expand our current understanding of sponge fauna as they constitute useful sentinel organisms.

year: 2021

title: Ngā Hua a Tāne Rore: The Benefits of Kapa Haka.

authors: Pihama, Leonie

abstract: This report presentsthe findings of scoping research that is focused on developing a research agenda that will enable a greater understanding of the value and contribution of kapa haka to Aotearoa New Zealand society, and which explores the multiple ways in which we may view the value and contribution of kapa haka within cultural, social and economic contexts.
• There was a unanimous and resounding view that kapa haka does indeed make a valuable contribution to Aotearoa New Zealand society, but that its value is not fully understood or acknowledged within Aotearoa New Zealand.
• The most important components of kapa haka are its intrinsic link to culture and Māori identity, and the essential element of whanaungatanga, the importance of people and connectedness.
• Kapa haka has a dynamic role as a vehicle for the revitalisation and retention of te reo, tikanga, ritual processes and histories.
• It is perceived as a gateway into the culture for Māori who are disengaged from their marae/hapū/iwi, as well as as a safe, inclusive activity through which all New Zealanders can engage with Māori culture.
• Kapa haka is seen as a medium for fostering a richer, more cohesive and inclusive society in Aotearoa New Zealand. As such, it makes a major contribution to building and strengthening New Zealand’s nationhood.
• Kapa haka makes a significant contribution to New Zealand’s national identity and how we are represented and viewed internationally. It provides an effective platform for creating meaningful connections with other nations and peoples.
• Māori culture/kapa haka is increasingly utilised to add value to many forums, both formal and informal, within the public and government sectors. This was seen by some to reflect a more embracing attitude toward Māori cultural protocols as a normal part of New Zealand’s social fabric.
• Kapa haka is not, however, being given the status or respect it deserves as a cultural icon. Because its significance is not well understood by non-Māori, particularly at the level of government, it is often treated in a tokenistic way.
• A major component of kapa haka is its power to effect wellbeing, and to positively transform the lives of individuals and communities. A strength of the movement towards increased health and fitness within kapa haka is that it is achieved collectively.
• An important social benefit of kapa haka is that it provides a positive, disciplined, strength-based environment for rangatahi.
• Kapa haka is having a powerful, transformative impact on social outcomes through the BMPA (Māori performing arts degree), which enables people involved in kapa haka who would otherwise never have considered tertiary education as an option, to embark on that journey and exceed their
own expectations.
• An overall feeling of optimism about the future of kapa haka was tempered by the conviction that there was much more potential to be explored within the realm of kapa haka, particularly in terms of its social benefits.
• The myriad benefits of kapa haka within school environments, including improved learning outcomes, were clearly attested to. However, some barriers to realising those improved outcomes were also identified.
• Some participants were very sure ofthe economic value of kapa haka to Aotearoa. Whilemost of them were less able to articulate specific economic outcomes, they nonetheless had a definite sense of the link between the cultural, social and economic, and that that was ofsignificant value.
• The immense value of ‘culture-to-culture’ relationships was identified, with Maōri culture, including kapa haka, playing a significant role in laying the foundations for lasting trade relationships with other nations, and other cultures.
• Two significant and largely unacknowledged areas of economic contribution were identified: the ‘silent’ economy generated by kapa haka activities; and the extensive ‘productivity’ activity around voluntary workers involved in kapa haka.
• There was an overall view that the economic potential of kapa haka is underestimated and needs to be explored more fully, including the potential for engagement with New Zealand’s private sector.
• A recurrent theme that emerged around the value of kapa haka was to do with how we should go about measuring the value of culture, knowledge and art, and how ‘value’ itselfshould be defined and measured.
• Economic challenges were identified, especially in terms of financial hardship for those involved in kapa haka at the competitive level. It was also noted, however, that kapa haka communities are naturally adept and endlessly resourceful at generating funds.
• The issue of sustainability was raised by some participants who were concerned that kapa haka should be supported at every level into the future, and not just at the high-end competitive level.
• Of fundamental importance was that the growth and development of kapa haka should take place within the context of the acceptance and embracing of Māori culture as an integral component of New Zealand identity and nationhood.

text: Ngā Hua a Tāne Rore: The Benefits of Kapa Haka. This report presentsthe findings of scoping research that is focused on developing a research agenda that will enable a greater understanding of the value and contribution of kapa haka to Aotearoa New Zealand society, and which explores the multiple ways in which we may view the value and contribution of kapa haka within cultural, social and economic contexts.
• There was a unanimous and resounding view that kapa haka does indeed make a valuable contribution to Aotearoa New Zealand society, but that its value is not fully understood or acknowledged within Aotearoa New Zealand.
• The most important components of kapa haka are its intrinsic link to culture and Māori identity, and the essential element of whanaungatanga, the importance of people and connectedness.
• Kapa haka has a dynamic role as a vehicle for the revitalisation and retention of te reo, tikanga, ritual processes and histories.
• It is perceived as a gateway into the culture for Māori who are disengaged from their marae/hapū/iwi, as well as as a safe, inclusive activity through which all New Zealanders can engage with Māori culture.
• Kapa haka is seen as a medium for fostering a richer, more cohesive and inclusive society in Aotearoa New Zealand. As such, it makes a major contribution to building and strengthening New Zealand’s nationhood.
• Kapa haka makes a significant contribution to New Zealand’s national identity and how we are represented and viewed internationally. It provides an effective platform for creating meaningful connections with other nations and peoples.
• Māori culture/kapa haka is increasingly utilised to add value to many forums, both formal and informal, within the public and government sectors. This was seen by some to reflect a more embracing attitude toward Māori cultural protocols as a normal part of New Zealand’s social fabric.
• Kapa haka is not, however, being given the status or respect it deserves as a cultural icon. Because its significance is not well understood by non-Māori, particularly at the level of government, it is often treated in a tokenistic way.
• A major component of kapa haka is its power to effect wellbeing, and to positively transform the lives of individuals and communities. A strength of the movement towards increased health and fitness within kapa haka is that it is achieved collectively.
• An important social benefit of kapa haka is that it provides a positive, disciplined, strength-based environment for rangatahi.
• Kapa haka is having a powerful, transformative impact on social outcomes through the BMPA (Māori performing arts degree), which enables people involved in kapa haka who would otherwise never have considered tertiary education as an option, to embark on that journey and exceed their
own expectations.
• An overall feeling of optimism about the future of kapa haka was tempered by the conviction that there was much more potential to be explored within the realm of kapa haka, particularly in terms of its social benefits.
• The myriad benefits of kapa haka within school environments, including improved learning outcomes, were clearly attested to. However, some barriers to realising those improved outcomes were also identified.
• Some participants were very sure ofthe economic value of kapa haka to Aotearoa. Whilemost of them were less able to articulate specific economic outcomes, they nonetheless had a definite sense of the link between the cultural, social and economic, and that that was ofsignificant value.
• The immense value of ‘culture-to-culture’ relationships was identified, with Maōri culture, including kapa haka, playing a significant role in laying the foundations for lasting trade relationships with other nations, and other cultures.
• Two significant and largely unacknowledged areas of economic contribution were identified: the ‘silent’ economy generated by kapa haka activities; and the extensive ‘productivity’ activity around voluntary workers involved in kapa haka.
• There was an overall view that the economic potential of kapa haka is underestimated and needs to be explored more fully, including the potential for engagement with New Zealand’s private sector.
• A recurrent theme that emerged around the value of kapa haka was to do with how we should go about measuring the value of culture, knowledge and art, and how ‘value’ itselfshould be defined and measured.
• Economic challenges were identified, especially in terms of financial hardship for those involved in kapa haka at the competitive level. It was also noted, however, that kapa haka communities are naturally adept and endlessly resourceful at generating funds.
• The issue of sustainability was raised by some participants who were concerned that kapa haka should be supported at every level into the future, and not just at the high-end competitive level.
• Of fundamental importance was that the growth and development of kapa haka should take place within the context of the acceptance and embracing of Māori culture as an integral component of New Zealand identity and nationhood.

year: 2014