title: Internal versus external control of calcium nutrition in kiwifruit

authors: Montanaro, Giuseppe

subjects: Actinidia deliciosa

abstract: Higher calcium (Ca) concentration in several fleshy fruit including kiwifruit is a pre-requisite for lower incidence of Ca-related diseases and improved fruit nutritional value. This review examines the internal and external factors operating along the soil-to-fruit pathway that are involved in the uptake and partitioning of Ca in kiwifruit vines. After a brief description of fruit growth and the dynamic of nutrient accumulation during fruit development, the review considers the role of soil Ca concentration and availability, root elongation, mass flow in the apoplast, fruit transpiration, competition between fruit and highly transpiring leaves, weather variables and soil moisture. How fruit morphological and anatomical traits, including skin anatomy, xylem development and hydraulic resistance, influence physiological processes such as transpiration and impact on Ca accumulation is also discussed. The review highlights that approximately 80% of the total Ca content of fruit is accumulated during the early weeks after fruit-set, suggesting that failure of good fruit Ca nutrition at that time may lead to poor fruit Ca content at harvest. Therefore, based on the analysis of the internal and external factors that influence Ca accumulation, recommendations are made for orchard practices that maximize Ca accumulation in the kiwifruit berry, including optimal pollination, nutrient and irrigation management, and manipulation of canopy architecture.

text: Internal versus external control of calcium nutrition in kiwifruit Higher calcium (Ca) concentration in several fleshy fruit including kiwifruit is a pre-requisite for lower incidence of Ca-related diseases and improved fruit nutritional value. This review examines the internal and external factors operating along the soil-to-fruit pathway that are involved in the uptake and partitioning of Ca in kiwifruit vines. After a brief description of fruit growth and the dynamic of nutrient accumulation during fruit development, the review considers the role of soil Ca concentration and availability, root elongation, mass flow in the apoplast, fruit transpiration, competition between fruit and highly transpiring leaves, weather variables and soil moisture. How fruit morphological and anatomical traits, including skin anatomy, xylem development and hydraulic resistance, influence physiological processes such as transpiration and impact on Ca accumulation is also discussed. The review highlights that approximately 80% of the total Ca content of fruit is accumulated during the early weeks after fruit-set, suggesting that failure of good fruit Ca nutrition at that time may lead to poor fruit Ca content at harvest. Therefore, based on the analysis of the internal and external factors that influence Ca accumulation, recommendations are made for orchard practices that maximize Ca accumulation in the kiwifruit berry, including optimal pollination, nutrient and irrigation management, and manipulation of canopy architecture.

year: 2014-10-08

title: Root Biomass under Range of Pasture Swards -Implications for Soil Carbon Stocks

authors: Jordan, Olivia Margaret

subjects: root biomass

abstract: Soil carbon (C) is the largest terrestrial store of carbon, greater than all other pools combined. Root biomass is recognised as an important contributor to the accumulation of soil C and recent studies have suggested that a higher diversity of plant species with higher root biomass may increase soil C content. Maintenance of soil C stocks is important as losses can contribute to increased greenhouse gas emissions. Furthermore soil C is important for maintaining soil quality. Much of New Zealand agricultural land is under pastoral grazing and is the greatest contributor to national greenhouse gas emissions from land. The potential for storing additional soil C in pasture soils is poorly understood. This study has assessed root biomass and carbon contents of soils under a range of pasture diversities and species composition to determine whether (i) there is greater root biomass under increasing plant diversity, (ii) changes in root properties between diversity treatments are evident and (iii) there is variation in root biomass between seasons. 
Soil samples were collected from an existing small plot trial managed by DairyNZ and Landcare Research containing 14 different mixtures of pasture species (three replicates per treatment). From each plot, fifteen soil cores were taken to a depth of 60cm, and bulked by 10cm depth increments. Root characteristics were determined after removing soil via scanning and analysing with WinRHIZO©, and subsequently root biomass determined following oven drying and weighing. A sub-sample of soil was also taken for C and nitrogen (N) analysis by combustion furnace. 
While there were no significant differences in root biomass with individual treatments, plots which had a presence of herb species chicory and plantain, resulted in a lesser root biomass when compared with plots without herb species. This would imply that while the use of herb species is desirable for above-ground production and drought tolerance, they provide limited potential for increasing C input to soil. Root characteristics determined that the use of tall fescue as a base grass resulted in a reduced root length density (RLD, root length per volume of soil to 60 cm), specific root length (SRL) and an increased average diameter compared with ryegrass based pastures. These characteristics promote increased root longevity in soil.

text: Root Biomass under Range of Pasture Swards -Implications for Soil Carbon Stocks Soil carbon (C) is the largest terrestrial store of carbon, greater than all other pools combined. Root biomass is recognised as an important contributor to the accumulation of soil C and recent studies have suggested that a higher diversity of plant species with higher root biomass may increase soil C content. Maintenance of soil C stocks is important as losses can contribute to increased greenhouse gas emissions. Furthermore soil C is important for maintaining soil quality. Much of New Zealand agricultural land is under pastoral grazing and is the greatest contributor to national greenhouse gas emissions from land. The potential for storing additional soil C in pasture soils is poorly understood. This study has assessed root biomass and carbon contents of soils under a range of pasture diversities and species composition to determine whether (i) there is greater root biomass under increasing plant diversity, (ii) changes in root properties between diversity treatments are evident and (iii) there is variation in root biomass between seasons. 
Soil samples were collected from an existing small plot trial managed by DairyNZ and Landcare Research containing 14 different mixtures of pasture species (three replicates per treatment). From each plot, fifteen soil cores were taken to a depth of 60cm, and bulked by 10cm depth increments. Root characteristics were determined after removing soil via scanning and analysing with WinRHIZO©, and subsequently root biomass determined following oven drying and weighing. A sub-sample of soil was also taken for C and nitrogen (N) analysis by combustion furnace. 
While there were no significant differences in root biomass with individual treatments, plots which had a presence of herb species chicory and plantain, resulted in a lesser root biomass when compared with plots without herb species. This would imply that while the use of herb species is desirable for above-ground production and drought tolerance, they provide limited potential for increasing C input to soil. Root characteristics determined that the use of tall fescue as a base grass resulted in a reduced root length density (RLD, root length per volume of soil to 60 cm), specific root length (SRL) and an increased average diameter compared with ryegrass based pastures. These characteristics promote increased root longevity in soil.

year: 2015

title: Restoring the flow: Challenging the existing management frameworks to integrate Mātauranga Māori

authors: Hall, Tredegar Rangiātea

subjects: tangata whenua water management

abstract: Within the context of the current regimes of fresh water management in Aotearoa, this thesis is an exploration of the significance of freshwater to Māori; our rangatiratanga, Treaty rights and ownership. The Māori world view and the way this relates to fresh water is described and contrasted with the principles and practices of water management in the contemporary neo-liberal governance structures of this country. The impacts of the commodification of water through ownership rights, the limited monitoring capacity and the inability to provide a governance structure that will work across diverse environments are seen to threaten the sustainability of a critical part of our environment. The primary focus of on this research is on the relationship between the exclusion of tangata whenua from decision making in resource management and the degradation of the environment.
 
The thesis comments on the development of resource management legislation and actions of the state in Aotearoa, and uses post-colonial theory as a starting point to document the subordinate relationship of Māori within contemporary governance. This has privileged mono-cultural and neoliberal forms of water management that has scarred Papatūānuku and threatens human sustainability into the future.
    
The recent co-management agreement for the Waikato River is the specific case study against which a recent effort to reduce the alienation of Māori is viewed. A kaupapa Māori methodology is used to acquire and understand the importance of mātauranga Māori/ Traditional Ecological Knowledge (TEK) and what is required for these principles to enhance water management practices within the case study area. The original contribution of the work is drawn from interviews conducted with Māori and others who are involved in or informed by the commitment to explore co-management sustainable management options. These views are woven into a substantial and interpretative commentary on the role of Māori in future water governance.

The thesis argues that the best way to enhance water management and environmental protection is by inducing a planning paradigm shift where tangata whenua are given greater influence in environmental decision making that resembles an equal Treaty of Waitangi partnership, where the ethic of kaitiakitanga is empowered. Such a strategy would allow decision making regarding water and environmental management to be more focused on what is best for the resource and its survival rather than what most cost effective for some owners of water rights. Encouraging the acceptance of mātauranga Māori and incorporating more efficient and sustainable innovative technologies can restore the mauri of water in our place.

text: Restoring the flow: Challenging the existing management frameworks to integrate Mātauranga Māori Within the context of the current regimes of fresh water management in Aotearoa, this thesis is an exploration of the significance of freshwater to Māori; our rangatiratanga, Treaty rights and ownership. The Māori world view and the way this relates to fresh water is described and contrasted with the principles and practices of water management in the contemporary neo-liberal governance structures of this country. The impacts of the commodification of water through ownership rights, the limited monitoring capacity and the inability to provide a governance structure that will work across diverse environments are seen to threaten the sustainability of a critical part of our environment. The primary focus of on this research is on the relationship between the exclusion of tangata whenua from decision making in resource management and the degradation of the environment.
 
The thesis comments on the development of resource management legislation and actions of the state in Aotearoa, and uses post-colonial theory as a starting point to document the subordinate relationship of Māori within contemporary governance. This has privileged mono-cultural and neoliberal forms of water management that has scarred Papatūānuku and threatens human sustainability into the future.
    
The recent co-management agreement for the Waikato River is the specific case study against which a recent effort to reduce the alienation of Māori is viewed. A kaupapa Māori methodology is used to acquire and understand the importance of mātauranga Māori/ Traditional Ecological Knowledge (TEK) and what is required for these principles to enhance water management practices within the case study area. The original contribution of the work is drawn from interviews conducted with Māori and others who are involved in or informed by the commitment to explore co-management sustainable management options. These views are woven into a substantial and interpretative commentary on the role of Māori in future water governance.

The thesis argues that the best way to enhance water management and environmental protection is by inducing a planning paradigm shift where tangata whenua are given greater influence in environmental decision making that resembles an equal Treaty of Waitangi partnership, where the ethic of kaitiakitanga is empowered. Such a strategy would allow decision making regarding water and environmental management to be more focused on what is best for the resource and its survival rather than what most cost effective for some owners of water rights. Encouraging the acceptance of mātauranga Māori and incorporating more efficient and sustainable innovative technologies can restore the mauri of water in our place.

year: 2012