title: Planning the urban foodscape: Policy and regulation of urban agriculture in Aotearoa New Zealand

authors: Hanna, Christina Jane

abstract: Policy support for urban agriculture (UA) has increased internationally in the past decade, driven by factors such as urban decay, food insecurity, climate change and disasters, self-determination efforts and the Covid-19 pandemic. To date, there has been little analysis of the emergent practices across different cities in Aotearoa New Zealand. To address this gap, we examine key aspects of UA in Aotearoa and assess the application of local plans and regulation to determine how UA is defined and treated in the four most populous cities. The results reveal a lack of specific attention to and policy direction for UA. This vacuum is compounded by purpose-driven zoning typologies, restrictive resource use controls, scant provision for Māori food practices and a failure to keep pace with the changing forms of UA. The results identify the need for cities to review and clarify provision for UA, to create greater certainty and where appropriate, facilitation of food sovereignty and diverse urban foodscapes.

text: Planning the urban foodscape: Policy and regulation of urban agriculture in Aotearoa New Zealand Policy support for urban agriculture (UA) has increased internationally in the past decade, driven by factors such as urban decay, food insecurity, climate change and disasters, self-determination efforts and the Covid-19 pandemic. To date, there has been little analysis of the emergent practices across different cities in Aotearoa New Zealand. To address this gap, we examine key aspects of UA in Aotearoa and assess the application of local plans and regulation to determine how UA is defined and treated in the four most populous cities. The results reveal a lack of specific attention to and policy direction for UA. This vacuum is compounded by purpose-driven zoning typologies, restrictive resource use controls, scant provision for Māori food practices and a failure to keep pace with the changing forms of UA. The results identify the need for cities to review and clarify provision for UA, to create greater certainty and where appropriate, facilitation of food sovereignty and diverse urban foodscapes.

year: 2021

title: Piri Pāua: Mātauranga Māori and marine science approach to growth rate and length at maturity of pāua in the Bay of Plenty 2022-2024

authors: Paul-Burke, Kura

abstract: Pāua is a highly regarded taonga (culturally important) species. Mai i ngā Kurī ā Whārei ki Tihirau (the Bay of Plenty Regional Iwi Customary Fisheries Forum) raised concerns about the current state of pāua in Te Moana-a-Toi (Bay of Plenty). This project utilised localised intergenerational observations of population dynamics in traditional harvesting areas to assess pāua productivity in the Tauranga Moana Mātaitai Reserve in Tauranga and Te Rohe Moana o Ngāti Awa in Whakatāne. The project combined mātauranga Māori alongside marine science field methods.

Results were compared with previous iwi-led research at Tauranga in 2013 and Whakatāne in 2010. The pāua population in 2023 had declined by almost half in Tauranga but remained relatively consistent across all sites in Whakatāne. However, pāua were small sized in both locations, with less than 1% of individuals reaching the Minimum Legal Size (125 mm) for harvesting. Growth rate surveys were conducted in the wild at both locations from June 2023 to the end of May 2024 and identified pāua as slow growing and, as a result, sexually mature at smaller sizes than in other regions of Aotearoa New Zealand.

text: Piri Pāua: Mātauranga Māori and marine science approach to growth rate and length at maturity of pāua in the Bay of Plenty 2022-2024 Pāua is a highly regarded taonga (culturally important) species. Mai i ngā Kurī ā Whārei ki Tihirau (the Bay of Plenty Regional Iwi Customary Fisheries Forum) raised concerns about the current state of pāua in Te Moana-a-Toi (Bay of Plenty). This project utilised localised intergenerational observations of population dynamics in traditional harvesting areas to assess pāua productivity in the Tauranga Moana Mātaitai Reserve in Tauranga and Te Rohe Moana o Ngāti Awa in Whakatāne. The project combined mātauranga Māori alongside marine science field methods.

Results were compared with previous iwi-led research at Tauranga in 2013 and Whakatāne in 2010. The pāua population in 2023 had declined by almost half in Tauranga but remained relatively consistent across all sites in Whakatāne. However, pāua were small sized in both locations, with less than 1% of individuals reaching the Minimum Legal Size (125 mm) for harvesting. Growth rate surveys were conducted in the wild at both locations from June 2023 to the end of May 2024 and identified pāua as slow growing and, as a result, sexually mature at smaller sizes than in other regions of Aotearoa New Zealand.

year: 2025

title: Protein intercalated bentonite recovered using adsorption from stickwater

authors: Verbeek, Casparus Johan R.

subjects: bentonite

abstract: Wastewater from the meat rendering industry is called stickwater and contains about 4 wt% protein and has a high biological oxygen demand (approximately 150,000 mg/l). Large volumes require treatment prior to disposal, leading to a potentially useful source of protein being lost. In this study the organic fraction of stickwater (largely protein) was recovered by adsorption onto bentonite followed by centrifugation. Adsorption behavior was examined for a range of pH and clay concentrations. Equilibrium behaviour was described using the Langmuir–Freundlich isotherm. 25% organics can be recovered from stickwater without clay at pH below 5. Organic matter recovery was between 75 and 90% at 1 g clay per 20 g solution. Recovery decreased with increasing pH above pH 7–25% at pH 12, but was independent of pH at higher clay concentrations. Bentonite basal spacing increased from 13 to 23.5 Å for all pHs showing that protein had intercalated between clay layers. At high pH, bentonite had a positive charge on its edges, giving an expanded structure with a low pellet density at 17% solids, whereas at pH below 5 pellet density was between 25 and 33% solids. This has implications for downstream processing because more water would need to be removed, increasing downstream processing costs. Using between 5 and 10 g clay/200 g solution, adsorption was sufficient to give greater than 60% organics recovery. Processing would therefore be a trade off between using as as little as possible clay to minimise cost and maximise percentage organics adsorbed per gram of clay, while maximising recovery and maintaining small process volumes.

text: Protein intercalated bentonite recovered using adsorption from stickwater Wastewater from the meat rendering industry is called stickwater and contains about 4 wt% protein and has a high biological oxygen demand (approximately 150,000 mg/l). Large volumes require treatment prior to disposal, leading to a potentially useful source of protein being lost. In this study the organic fraction of stickwater (largely protein) was recovered by adsorption onto bentonite followed by centrifugation. Adsorption behavior was examined for a range of pH and clay concentrations. Equilibrium behaviour was described using the Langmuir–Freundlich isotherm. 25% organics can be recovered from stickwater without clay at pH below 5. Organic matter recovery was between 75 and 90% at 1 g clay per 20 g solution. Recovery decreased with increasing pH above pH 7–25% at pH 12, but was independent of pH at higher clay concentrations. Bentonite basal spacing increased from 13 to 23.5 Å for all pHs showing that protein had intercalated between clay layers. At high pH, bentonite had a positive charge on its edges, giving an expanded structure with a low pellet density at 17% solids, whereas at pH below 5 pellet density was between 25 and 33% solids. This has implications for downstream processing because more water would need to be removed, increasing downstream processing costs. Using between 5 and 10 g clay/200 g solution, adsorption was sufficient to give greater than 60% organics recovery. Processing would therefore be a trade off between using as as little as possible clay to minimise cost and maximise percentage organics adsorbed per gram of clay, while maximising recovery and maintaining small process volumes.

year: 2011