title: Understanding the response of nitrifying communities to disturbance in the mcmurdo dry valleys, Antarctica

authors: Monteiro, Maria R.

subjects: Science & Technology

abstract: © 2020 by the authors. Licensee MDPI, Basel, Switzerland. Polar ecosystems are generally limited in nitrogen (N) nutrients, and the patchy availability of N is partly determined by biological pathways, such as nitrification, which are carried out by distinctive prokaryotic functional groups. The activity and diversity of microorganisms are generally strongly influenced by environmental conditions. However, we know little of the attributes that control the distribution and activity of specific microbial functional groups, such as nitrifiers, in extreme cold environments and how they may respond to change. To ascertain relationships between soil geochemistry and the ecology of nitrifying microbial communities, we carried out a laboratory-based manipulative experiment to test the selective effect of key geochemical variables on the activity and abundance of ammonia-oxidizing communities in soils from the McMurdo Dry Valleys of Antarctica. We hypothesized that nitrifying communities, adapted to different environmental conditions within the Dry Valleys, will have distinct responses when submitted to similar geochemical disturbances. In order to test this hypothesis, soils from two geographically distant and geochemically divergent locations, Miers and Beacon Valleys, were incubated over 2 months under increased conductivity, ammonia concentration, copper concentration, and organic matter content. Amplicon sequencing of the 16S rRNA gene and transcripts allowed comparison of the response of ammonia-oxidizing Archaea (AOA) and ammonia-oxidizing Bacteria (AOB) to each treatment over time. This approach was combined with measurements of15NH4+ oxidation rates using15N isotopic additions. Our results showed a higher potential for nitrification in Miers Valley, where environmental conditions are milder relative to Beacon Valley. AOA exhibited better adaptability to geochemical changes compared to AOB, particularly to the increase in copper and conductivity. AOA were also the only nitrifying group found in Beacon Valley soils. This laboratorial manipulative experiment provided new knowledge on how nitrifying groups respond to changes on key geochemical variables of Antarctic desert soils, and we believe these results offer new insights on the dynamics of N cycling in these ecosystems.

text: Understanding the response of nitrifying communities to disturbance in the mcmurdo dry valleys, Antarctica © 2020 by the authors. Licensee MDPI, Basel, Switzerland. Polar ecosystems are generally limited in nitrogen (N) nutrients, and the patchy availability of N is partly determined by biological pathways, such as nitrification, which are carried out by distinctive prokaryotic functional groups. The activity and diversity of microorganisms are generally strongly influenced by environmental conditions. However, we know little of the attributes that control the distribution and activity of specific microbial functional groups, such as nitrifiers, in extreme cold environments and how they may respond to change. To ascertain relationships between soil geochemistry and the ecology of nitrifying microbial communities, we carried out a laboratory-based manipulative experiment to test the selective effect of key geochemical variables on the activity and abundance of ammonia-oxidizing communities in soils from the McMurdo Dry Valleys of Antarctica. We hypothesized that nitrifying communities, adapted to different environmental conditions within the Dry Valleys, will have distinct responses when submitted to similar geochemical disturbances. In order to test this hypothesis, soils from two geographically distant and geochemically divergent locations, Miers and Beacon Valleys, were incubated over 2 months under increased conductivity, ammonia concentration, copper concentration, and organic matter content. Amplicon sequencing of the 16S rRNA gene and transcripts allowed comparison of the response of ammonia-oxidizing Archaea (AOA) and ammonia-oxidizing Bacteria (AOB) to each treatment over time. This approach was combined with measurements of15NH4+ oxidation rates using15N isotopic additions. Our results showed a higher potential for nitrification in Miers Valley, where environmental conditions are milder relative to Beacon Valley. AOA exhibited better adaptability to geochemical changes compared to AOB, particularly to the increase in copper and conductivity. AOA were also the only nitrifying group found in Beacon Valley soils. This laboratorial manipulative experiment provided new knowledge on how nitrifying groups respond to changes on key geochemical variables of Antarctic desert soils, and we believe these results offer new insights on the dynamics of N cycling in these ecosystems.

year: 2020-03-13

title: Collaboration between unions in a multi-union, non-exclusive bargaining regime: What can Canada learn from New Zealand?

authors: Harcourt, Mark

abstract: The Canadian union certification system guarantees workers rights to organise, bargain collectively, and strike only when a majority of co-workers favours unionisation. This contravenes International Labour Organisation standards, in which the freedom to associate is unqualified by majority support. In recent years, the Supreme Court of Canada has drawn on ILO principles to interpret constitutional rights as covering organising and collective bargaining activities related to freedom of association under section 2(d) of the Charter of Rights and Freedoms. However, it has not as yet ordered Canadian governments to enact labour relations laws consistent with these new constitutional rights. Neither has there been a general call for such legislative change. Instead, many fear that statutory support for non-majority unionism would lead to multi-union representation and intensified inter-union competition, but fail to consider that sharing the workplace might actually promote inter-union cooperation against a common adversary in management. This study addresses this shortcoming by looking at the extent and nature of inter-union collaboration in New Zealand, where non-majority, non-exclusive representation exists already. Collaboration was found to be common, not only over bargaining and lobbying, but also in organising. Implications for Canada are explored.

text: Collaboration between unions in a multi-union, non-exclusive bargaining regime: What can Canada learn from New Zealand? The Canadian union certification system guarantees workers rights to organise, bargain collectively, and strike only when a majority of co-workers favours unionisation. This contravenes International Labour Organisation standards, in which the freedom to associate is unqualified by majority support. In recent years, the Supreme Court of Canada has drawn on ILO principles to interpret constitutional rights as covering organising and collective bargaining activities related to freedom of association under section 2(d) of the Charter of Rights and Freedoms. However, it has not as yet ordered Canadian governments to enact labour relations laws consistent with these new constitutional rights. Neither has there been a general call for such legislative change. Instead, many fear that statutory support for non-majority unionism would lead to multi-union representation and intensified inter-union competition, but fail to consider that sharing the workplace might actually promote inter-union cooperation against a common adversary in management. This study addresses this shortcoming by looking at the extent and nature of inter-union collaboration in New Zealand, where non-majority, non-exclusive representation exists already. Collaboration was found to be common, not only over bargaining and lobbying, but also in organising. Implications for Canada are explored.

year: 2012

title: Working across cultures in indigenous science education

authors: Michie, Michael George

subjects: cross-cultural

abstract: The research in this thesis considers the ability of westerners, primarily teachers, to work cross-culturally with indigenous students in four of the settler states, Australia, New Zealand, Canada and the USA. It looks particularly at identity learning as a way in which westerners enhance their understanding and attitudes to another culture. Identity learning, and culture shock as an associated process, is examined in relation to the ideas of border crossing and culture brokerage. A number of issues were raised, some through the literature, which became foci for the research. Examination of border crossing indicated that some westerners were successful as cross-cultural communicators but did not suggest why. Discussions of cultural borders gave rise to their critique as being essentialised but failed to suggest how this was to be overcome. Anthropological models did not give any characterisation to the role of culture broker, although the ethnohistory literature gave some insight. The influence of culture shock on westerners working in indigenous communities in the settler states was not particularly understood nor its relationship to identity learning explored. A qualitative methodology is used involving a series of interviews with eight participants who were considered to be experienced in cross-cultural communication with a background in education. From the interviews a series of narratives were written which revealed their experiences and understandings particularly about their border crossings, culture brokerage and opinions regarding teaching indigenous students and teaching them science. These narratives became the major source of data for analysis. This research shows that many westerners who are successful working in cross-cultural settings value the culture of their indigenous hosts. This is the consequence of enhanced identity learning and can be the result of culture shock. Not all westerners learn to value the other culture and may either leave the community or stay for some other reason. Border crossers are able to think beyond the limitations of an essentialised ‘we and they’ dichotomy and locate themselves in other ways relative to the border. Culture brokerage is a strategy that individuals choose to use, sometimes on the behalf of a government or institution. The characteristics of an effective culture broker are those of a border crosser and this establishes a nexus between border crossing and culture brokerage. Suggestions regarding preparation to teach in indigenous communities reflect the enhancement of identity learning and promotion of border crossing. Preservice training should include experience practicum teaching with indigenous students. Effective teaching of indigenous students could be supported by hiring experienced teachers and extending their stays. All teachers who go to work in indigenous communities need to be aware of culture shock and its possible impact and mechanisms for minimising its impact need to be established through mentoring programs. The context of the students needs to be taken into account by consideration of their culture and appropriate interpretation of the curriculum and implementation of teaching strategies. Teachers need to acknowledge that they are in positions of power but need to negotiate that respectfully with their indigenous students. As teachers of science they need to have a more inclusive idea of the nature of science so they can facilitate the border crossings of their indigenous students.

text: Working across cultures in indigenous science education The research in this thesis considers the ability of westerners, primarily teachers, to work cross-culturally with indigenous students in four of the settler states, Australia, New Zealand, Canada and the USA. It looks particularly at identity learning as a way in which westerners enhance their understanding and attitudes to another culture. Identity learning, and culture shock as an associated process, is examined in relation to the ideas of border crossing and culture brokerage. A number of issues were raised, some through the literature, which became foci for the research. Examination of border crossing indicated that some westerners were successful as cross-cultural communicators but did not suggest why. Discussions of cultural borders gave rise to their critique as being essentialised but failed to suggest how this was to be overcome. Anthropological models did not give any characterisation to the role of culture broker, although the ethnohistory literature gave some insight. The influence of culture shock on westerners working in indigenous communities in the settler states was not particularly understood nor its relationship to identity learning explored. A qualitative methodology is used involving a series of interviews with eight participants who were considered to be experienced in cross-cultural communication with a background in education. From the interviews a series of narratives were written which revealed their experiences and understandings particularly about their border crossings, culture brokerage and opinions regarding teaching indigenous students and teaching them science. These narratives became the major source of data for analysis. This research shows that many westerners who are successful working in cross-cultural settings value the culture of their indigenous hosts. This is the consequence of enhanced identity learning and can be the result of culture shock. Not all westerners learn to value the other culture and may either leave the community or stay for some other reason. Border crossers are able to think beyond the limitations of an essentialised ‘we and they’ dichotomy and locate themselves in other ways relative to the border. Culture brokerage is a strategy that individuals choose to use, sometimes on the behalf of a government or institution. The characteristics of an effective culture broker are those of a border crosser and this establishes a nexus between border crossing and culture brokerage. Suggestions regarding preparation to teach in indigenous communities reflect the enhancement of identity learning and promotion of border crossing. Preservice training should include experience practicum teaching with indigenous students. Effective teaching of indigenous students could be supported by hiring experienced teachers and extending their stays. All teachers who go to work in indigenous communities need to be aware of culture shock and its possible impact and mechanisms for minimising its impact need to be established through mentoring programs. The context of the students needs to be taken into account by consideration of their culture and appropriate interpretation of the curriculum and implementation of teaching strategies. Teachers need to acknowledge that they are in positions of power but need to negotiate that respectfully with their indigenous students. As teachers of science they need to have a more inclusive idea of the nature of science so they can facilitate the border crossings of their indigenous students.

year: 2011