title: Review of best management practices for aquatic vegetation control in stormwater ponds, wetlands, and lakes

authors: de Winton, Mary

abstract: Auckland Council (AC) is responsible for the development and operation of a stormwater network across the region to avert risks to citizens and the environment.
Within this stormwater network, aquatic vegetation (including plants, unicellular and filamentous algae) can have both a positive and negative role in stormwater management and water quality treatment. The situations where management is needed to control aquatic vegetation are not always clear, and an inability to identify effective, feasible and economical control options may constrain management initiatives. AC (Infrastructure and Technical Services, Stormwater) commissioned this technical report to provide information for decision- making on aquatic vegetation management with in stormwater systems that are likely to experience vegetation-related issues.
Information was collated from a comprehensive literature review, augmented by knowledge held by the authors. This review identified a wide range of management practices that could be potentially employed. It also demonstrated complexities and uncertainties relating to these options that makes the identification of a best management practice difficult. Hence, the focus of this report was to enable users to screen for potential options, and use reference material provided on each option to confirm the best practice to employ for each situation.
The report identifies factors to define whether there is an aquatic vegetation problem (Section 3.0), and emphasises the need for agreed management goals for control (e.g. reduction, mitigation, containment, eradication). Resources to screen which management option(s) to employ are provided (Section 4.0), relating to the target aquatic vegetation, likely applicability of options to the system being managed, indicative cost, and ease of implementation. Initial screening allows users to shortlist potential control options for further reference (Section 5.0).
Thirty-five control options are described (Section 5.0) in sufficient detail to consider applicability to individual sites and species. These options are grouped under categories of biological, chemical or physical control. Biological control options involve the use of organisms to predate, infect or control vegetation growth (e.g. classical biological control) or manipulate conditions to control algal growth (e.g. pest fish removal, microbial products). Chemical control options involve the use of pesticides and chemicals (e.g. glyphosate, diquat), or the use of flocculants and nutrient inactivation products that are used to reduce nutrient loading, thereby decreasing algal growth. Physical control options involve removing vegetation or algal biomass (e.g. mechanical or manual harvesting), or setting up barriers to their growth (e.g. shading, bottom lining, sediment capping).
Preventative management options are usually the most cost effective, and these are also briefly described (Section 6.0). For example, the use of hygiene or quarantine protocols can reduce weed introductions or spread. Catchment- based practices to reduce sediment and nutrient sources to stormwater are likely to assist in the avoidance of algal and possibly aquatic plant problems. Nutrient removal may be a co-benefit where harvesting of submerged weed biomass is undertaken in stormwater systems. It should also be considered that removal of substantial amounts of submerged vegetation may result in a sudden and difficult-to-reverse s witch to a turbid, phytoplankton dominated state. Another possible solution is the conversion of systems that experience aquatic vegetation issues, to systems that are less likely to experience issues.
The focus of this report is on systems that receive significant stormwater inputs, i.e. constructed bodies, including ponds, amenity lakes, wetlands, and highly-modified receiving bodies. However, some information will have application to other natural water bodies.

text: Review of best management practices for aquatic vegetation control in stormwater ponds, wetlands, and lakes Auckland Council (AC) is responsible for the development and operation of a stormwater network across the region to avert risks to citizens and the environment.
Within this stormwater network, aquatic vegetation (including plants, unicellular and filamentous algae) can have both a positive and negative role in stormwater management and water quality treatment. The situations where management is needed to control aquatic vegetation are not always clear, and an inability to identify effective, feasible and economical control options may constrain management initiatives. AC (Infrastructure and Technical Services, Stormwater) commissioned this technical report to provide information for decision- making on aquatic vegetation management with in stormwater systems that are likely to experience vegetation-related issues.
Information was collated from a comprehensive literature review, augmented by knowledge held by the authors. This review identified a wide range of management practices that could be potentially employed. It also demonstrated complexities and uncertainties relating to these options that makes the identification of a best management practice difficult. Hence, the focus of this report was to enable users to screen for potential options, and use reference material provided on each option to confirm the best practice to employ for each situation.
The report identifies factors to define whether there is an aquatic vegetation problem (Section 3.0), and emphasises the need for agreed management goals for control (e.g. reduction, mitigation, containment, eradication). Resources to screen which management option(s) to employ are provided (Section 4.0), relating to the target aquatic vegetation, likely applicability of options to the system being managed, indicative cost, and ease of implementation. Initial screening allows users to shortlist potential control options for further reference (Section 5.0).
Thirty-five control options are described (Section 5.0) in sufficient detail to consider applicability to individual sites and species. These options are grouped under categories of biological, chemical or physical control. Biological control options involve the use of organisms to predate, infect or control vegetation growth (e.g. classical biological control) or manipulate conditions to control algal growth (e.g. pest fish removal, microbial products). Chemical control options involve the use of pesticides and chemicals (e.g. glyphosate, diquat), or the use of flocculants and nutrient inactivation products that are used to reduce nutrient loading, thereby decreasing algal growth. Physical control options involve removing vegetation or algal biomass (e.g. mechanical or manual harvesting), or setting up barriers to their growth (e.g. shading, bottom lining, sediment capping).
Preventative management options are usually the most cost effective, and these are also briefly described (Section 6.0). For example, the use of hygiene or quarantine protocols can reduce weed introductions or spread. Catchment- based practices to reduce sediment and nutrient sources to stormwater are likely to assist in the avoidance of algal and possibly aquatic plant problems. Nutrient removal may be a co-benefit where harvesting of submerged weed biomass is undertaken in stormwater systems. It should also be considered that removal of substantial amounts of submerged vegetation may result in a sudden and difficult-to-reverse s witch to a turbid, phytoplankton dominated state. Another possible solution is the conversion of systems that experience aquatic vegetation issues, to systems that are less likely to experience issues.
The focus of this report is on systems that receive significant stormwater inputs, i.e. constructed bodies, including ponds, amenity lakes, wetlands, and highly-modified receiving bodies. However, some information will have application to other natural water bodies.

year: 2013

title: Understanding the teacher upgrade programme in Samoa: Contextual challenges for in-service teachers, school principals and Ministry personnel

authors: Esera, Epenese

abstract: This article discusses the challenges involved in Samoa’s teacher upgrade programme. The teacher upgrade initiative came about because of the Samoan Ministry of Education, Sports and Culture’s aim for all in-service primary and secondary teachers to hold a Bachelor of Education degree. However, challenges including time scheduling, teachers’ wider responsibilities, unsupportive school principals, and communication barriers with the National University of Samoa appear to have hindered the programme’s implementation. This study employed a qualitative research approach which incorporated talanoa (rich conversation) as appropriate to the Samoan context. The findings from the talanoa sessions with teachers, principals and Ministry officials, highlight the social, cultural, educational and economic challenges that the teachers encountered on their qualification upgrade journeys. We argue that the challenges between the upgrading teachers, the schools, the National University of Samoa’s Faculty of Education and the Ministry could be being resolved through the Samoan notion of va (relational space) in which stakeholders generate mutual solutions to the challenges they encounter. This article concludes with recommendations for each of the partners involved in the upgrade programme in order to move forward.

text: Understanding the teacher upgrade programme in Samoa: Contextual challenges for in-service teachers, school principals and Ministry personnel This article discusses the challenges involved in Samoa’s teacher upgrade programme. The teacher upgrade initiative came about because of the Samoan Ministry of Education, Sports and Culture’s aim for all in-service primary and secondary teachers to hold a Bachelor of Education degree. However, challenges including time scheduling, teachers’ wider responsibilities, unsupportive school principals, and communication barriers with the National University of Samoa appear to have hindered the programme’s implementation. This study employed a qualitative research approach which incorporated talanoa (rich conversation) as appropriate to the Samoan context. The findings from the talanoa sessions with teachers, principals and Ministry officials, highlight the social, cultural, educational and economic challenges that the teachers encountered on their qualification upgrade journeys. We argue that the challenges between the upgrading teachers, the schools, the National University of Samoa’s Faculty of Education and the Ministry could be being resolved through the Samoan notion of va (relational space) in which stakeholders generate mutual solutions to the challenges they encounter. This article concludes with recommendations for each of the partners involved in the upgrade programme in order to move forward.

year: 2019

title: The gown and the korowai: Maori doctoral students and the spatial organization of academic knowledge

authors: Middleton, Sue

subjects: culture

abstract: This paper draws on 38 student interviews carried out in the course of the team research project Teaching and Learning in the Supervision of Māori Doctoral Students. Māori doctoral thesis work takes place in the intersections between the Māori (tribal) world of identifications and obligations, the organisational and epistemological configurations of academia, and the bureaucratic requirements of funding or employing bureaucracies. To explore how students accommodate cultural, academic and bureaucratic demands, we develop analytical tools combining three intellectual traditions: Māori educational theory, Bernstein’s sociology of the academy, and Lefebvre’s conceptual trilogy of perceived, conceived, and lived space.

text: The gown and the korowai: Maori doctoral students and the spatial organization of academic knowledge This paper draws on 38 student interviews carried out in the course of the team research project Teaching and Learning in the Supervision of Māori Doctoral Students. Māori doctoral thesis work takes place in the intersections between the Māori (tribal) world of identifications and obligations, the organisational and epistemological configurations of academia, and the bureaucratic requirements of funding or employing bureaucracies. To explore how students accommodate cultural, academic and bureaucratic demands, we develop analytical tools combining three intellectual traditions: Māori educational theory, Bernstein’s sociology of the academy, and Lefebvre’s conceptual trilogy of perceived, conceived, and lived space.

year: 2009