title: Pulp and paper effluent organic constituents interactions with soil matrices

authors: Lambie, Suzanne Margaret

abstract: The land application of pulp and paper effluents has the potential to be a long-term sustainable solution for the requirements of industry and regulatory control of environmental impacts. A critical aspect of its success will be that the soil matrix onto which the effluents are applied is able to assimilate and remove effluent organic constituents of environmental concern. Two important processes are required for this. Firstly, the soils need to rapidly attenuate the movement of these materials through the soil column to ensure that groundwater and surface water contamination is minimised. Secondly, the accumulated constituents need to be mineralised/degraded to ensure the capacity of the soil is not exceeded with repeated effluent applications. This study aimed to use laboratory-scale systems to determine the contribution of these mechanisms to the fate and behaviour of environmentally-significant pulp and paper effluent constituents. 

Resin acids (major effluent toxicants, bioaccumulative and persistent) and phytosterols (potential endocrine disruptors) were the focus of this work. Three potential land application soil types, sand, Kawerau soil, and Whakarewarewa soil were considered. Thermomechanical pulping effluent was the principal waste source for the study since it is most suitable for land application. Given the potential for effluents from other pulp and paper processes to be land applied to some degree, two other wastestreams, chemi-thermomechanical and bleached kraft effluents, were considered in a more limited fashion.

Resin acids were readily degradable in all the selected soils and with all effluent types. In most cases nearly 100% removal was obtained within 6 months incubation. The sand substrate was particularly effective in removing the compounds, possibly because of a lack of alternative carbon sources in the sand matrix. Effluent-derived acclimated microbiota may have been the principal degraders responsible for resin acid degradation. Resin acids were substantially degraded under both aerobic and anaerobic conditions. Thus, land application systems may be able to sustain resin acid removal performance even if anaerobic conditions are produced in the soils as a result of high rainfall/water table increases or over-irrigation.

Resin acids were rapidly absorbed to the soil matrices. A significant proportion of the resin acids were irreversibly adsorbed to the organic soils. The capacity and intensity of adsorption was correlated with soil carbon content. Whakarewarewa soil had the greatest sorption capacity and sand was least attentuative. High concentrations of dissolved organic carbon were leached from the Kawerau and Whakarewarewa soils. This soluble material may influence the partitioning behaviour of lipophilic compounds, such as resin acids, and thus their mobility.

Overall, this study has shown that resin acids can be very effectively removed from pulp and paper effluents when applied to a range of soils. Phytosterols were not attenuated as efficiently but are likely to be relatively immobile in the upper layers of the soil column. Other factors, such as salinity and nutrient loadings, are therefore likely to be more important limitations for the future utilisation of land application systems in the pulp and paper industry.

text: Pulp and paper effluent organic constituents interactions with soil matrices The land application of pulp and paper effluents has the potential to be a long-term sustainable solution for the requirements of industry and regulatory control of environmental impacts. A critical aspect of its success will be that the soil matrix onto which the effluents are applied is able to assimilate and remove effluent organic constituents of environmental concern. Two important processes are required for this. Firstly, the soils need to rapidly attenuate the movement of these materials through the soil column to ensure that groundwater and surface water contamination is minimised. Secondly, the accumulated constituents need to be mineralised/degraded to ensure the capacity of the soil is not exceeded with repeated effluent applications. This study aimed to use laboratory-scale systems to determine the contribution of these mechanisms to the fate and behaviour of environmentally-significant pulp and paper effluent constituents. 

Resin acids (major effluent toxicants, bioaccumulative and persistent) and phytosterols (potential endocrine disruptors) were the focus of this work. Three potential land application soil types, sand, Kawerau soil, and Whakarewarewa soil were considered. Thermomechanical pulping effluent was the principal waste source for the study since it is most suitable for land application. Given the potential for effluents from other pulp and paper processes to be land applied to some degree, two other wastestreams, chemi-thermomechanical and bleached kraft effluents, were considered in a more limited fashion.

Resin acids were readily degradable in all the selected soils and with all effluent types. In most cases nearly 100% removal was obtained within 6 months incubation. The sand substrate was particularly effective in removing the compounds, possibly because of a lack of alternative carbon sources in the sand matrix. Effluent-derived acclimated microbiota may have been the principal degraders responsible for resin acid degradation. Resin acids were substantially degraded under both aerobic and anaerobic conditions. Thus, land application systems may be able to sustain resin acid removal performance even if anaerobic conditions are produced in the soils as a result of high rainfall/water table increases or over-irrigation.

Resin acids were rapidly absorbed to the soil matrices. A significant proportion of the resin acids were irreversibly adsorbed to the organic soils. The capacity and intensity of adsorption was correlated with soil carbon content. Whakarewarewa soil had the greatest sorption capacity and sand was least attentuative. High concentrations of dissolved organic carbon were leached from the Kawerau and Whakarewarewa soils. This soluble material may influence the partitioning behaviour of lipophilic compounds, such as resin acids, and thus their mobility.

Overall, this study has shown that resin acids can be very effectively removed from pulp and paper effluents when applied to a range of soils. Phytosterols were not attenuated as efficiently but are likely to be relatively immobile in the upper layers of the soil column. Other factors, such as salinity and nutrient loadings, are therefore likely to be more important limitations for the future utilisation of land application systems in the pulp and paper industry.

year: 2000

title: Water column turbidity not sediment nutrient enrichment moderates microphytobenthic primary production

authors: Mangan, Stephanie

subjects: Science & Technology

abstract: Soft sediment intertidal habitats are under intense anthropogenic pressure resulting from increased land derived sediment and nutrient delivery. Long term, this can cause high water column turbidity and nutrient enrichment of sediment porewaters, which has cascading effects on coastal ecosystem functionality. However, how these stressors may interact and influence benthic productivity over alternating periods of submergence and emergence is largely unknown. This study investigates the effects of sediment nutrient enrichment (at three levels for 20 months) on benthic primary production at six sites in four New Zealand estuaries that spanned a gradient in water column turbidity. While nutrient enrichment had no detectable effect on microphytobenthic primary production, water column turbidity had a significant influence, explaining up to 40% of variability during tidal submergence, followed by temperature and sediment characteristics. In addition, negative net primary production (NPP) estimates and therefore net heterotrophy for the most turbid estuaries during tidal submergence resulted in an increased reliance on production during emerged periods, where NPP was positive across all sites. This study highlights the prominent role of water column turbidity over nutrient enrichment in moderating microphytobenthic production, and the increasing importance of emerged periods to maintain the health and functioning of coastal habitats.

text: Water column turbidity not sediment nutrient enrichment moderates microphytobenthic primary production Soft sediment intertidal habitats are under intense anthropogenic pressure resulting from increased land derived sediment and nutrient delivery. Long term, this can cause high water column turbidity and nutrient enrichment of sediment porewaters, which has cascading effects on coastal ecosystem functionality. However, how these stressors may interact and influence benthic productivity over alternating periods of submergence and emergence is largely unknown. This study investigates the effects of sediment nutrient enrichment (at three levels for 20 months) on benthic primary production at six sites in four New Zealand estuaries that spanned a gradient in water column turbidity. While nutrient enrichment had no detectable effect on microphytobenthic primary production, water column turbidity had a significant influence, explaining up to 40% of variability during tidal submergence, followed by temperature and sediment characteristics. In addition, negative net primary production (NPP) estimates and therefore net heterotrophy for the most turbid estuaries during tidal submergence resulted in an increased reliance on production during emerged periods, where NPP was positive across all sites. This study highlights the prominent role of water column turbidity over nutrient enrichment in moderating microphytobenthic production, and the increasing importance of emerged periods to maintain the health and functioning of coastal habitats.

year: 2020

title: Introduction and dedication to Matiu Dickson

authors: Te Aho, Linda

subjects: Dickson, Matiu

abstract: This edition of the Waikato Law Review is dedicated to our dear friend and colleague, Matiu Dickson, and we thank Judge Craig Coxhead for his wonderful tribute to Matiu. The morning of the 7th of April 2016 will forever be imprinted in our minds and hearts. Matiu passed away that morning having just delivered the final speech in the opening ceremony for our new Law Building here at Waikato University. It was said at his tangi that this was a high price to be paid for such a building. A price that we would never have chosen to pay. That price brings an obligation to honour and respect the legacy that Matiu has left us, his commitment to the Faculty’s founding goals and, in particular, the promotion of a bicultural legal education for Māori and non-Māori alike; that tikanga is recognised as the first law of Aotearoa New Zealand and continues to form a central part of our curriculum. Matiu personified the bicultural mission of Te Piringa Faculty of Law; that, through its curriculum, research activities and its structures, the Faculty would be the forefront of the development of a bicultural legal philosophy. Matiu worked hard to ensure this mission remained a stated goal of the Faculty and to give it meaning over his 20 year tenure. He constantly worked to infuse it into the structures and processes of this Law Faculty. He worked and campaigned for years, and successfully so, to make sure the name gifted to the Faculty by Dame Te Atairangikaahu at its founding, “Te Piringa”, became our Faculty’s officially recognised name. He was passionate about the use of te reo Māori in assessment. He encouraged and facilitated the use of te reo Māori mooting. It was our colleague, Ani Mikaere, who, during her time here as a legal academic, first publicly articulated tikanga Māori as the first law of Aotearoa. Through the years, Matiu and our academic colleagues, including Stephanie Milroy, Craig Coxhead, Caren Fox (all now Māori Land Court judges), Leah Whiu, Harata Paterson, Nan Seuffert, Ruth Bush, Wayne Rumbles, Robert Joseph, Valmaine Toki and ourselves, reaffirmed tikanga as the first law of Aotearoa in our teaching and research. Years later, the article “Lex Aotearoa: An Heroic Attempt to Map the Māori Dimension in Modern New Zealand Law” by Justice Joseph Williams2 developed the idea further and is currently the leading piece on the weaving of tikanga and Anglo-New Zealand law.3 Matiu Dickson was an expert in tikanga, the first law of Aotearoa. He lived it every day. He created and taught courses on it and made sure it was integrated throughout the curriculum. In Matiu’s honour, it is entirely appropriate that there are a number of contributions in this Review that have a Māori or Indigenous theme, and we hope future issues will likewise assure such a balance.

text: Introduction and dedication to Matiu Dickson This edition of the Waikato Law Review is dedicated to our dear friend and colleague, Matiu Dickson, and we thank Judge Craig Coxhead for his wonderful tribute to Matiu. The morning of the 7th of April 2016 will forever be imprinted in our minds and hearts. Matiu passed away that morning having just delivered the final speech in the opening ceremony for our new Law Building here at Waikato University. It was said at his tangi that this was a high price to be paid for such a building. A price that we would never have chosen to pay. That price brings an obligation to honour and respect the legacy that Matiu has left us, his commitment to the Faculty’s founding goals and, in particular, the promotion of a bicultural legal education for Māori and non-Māori alike; that tikanga is recognised as the first law of Aotearoa New Zealand and continues to form a central part of our curriculum. Matiu personified the bicultural mission of Te Piringa Faculty of Law; that, through its curriculum, research activities and its structures, the Faculty would be the forefront of the development of a bicultural legal philosophy. Matiu worked hard to ensure this mission remained a stated goal of the Faculty and to give it meaning over his 20 year tenure. He constantly worked to infuse it into the structures and processes of this Law Faculty. He worked and campaigned for years, and successfully so, to make sure the name gifted to the Faculty by Dame Te Atairangikaahu at its founding, “Te Piringa”, became our Faculty’s officially recognised name. He was passionate about the use of te reo Māori in assessment. He encouraged and facilitated the use of te reo Māori mooting. It was our colleague, Ani Mikaere, who, during her time here as a legal academic, first publicly articulated tikanga Māori as the first law of Aotearoa. Through the years, Matiu and our academic colleagues, including Stephanie Milroy, Craig Coxhead, Caren Fox (all now Māori Land Court judges), Leah Whiu, Harata Paterson, Nan Seuffert, Ruth Bush, Wayne Rumbles, Robert Joseph, Valmaine Toki and ourselves, reaffirmed tikanga as the first law of Aotearoa in our teaching and research. Years later, the article “Lex Aotearoa: An Heroic Attempt to Map the Māori Dimension in Modern New Zealand Law” by Justice Joseph Williams2 developed the idea further and is currently the leading piece on the weaving of tikanga and Anglo-New Zealand law.3 Matiu Dickson was an expert in tikanga, the first law of Aotearoa. He lived it every day. He created and taught courses on it and made sure it was integrated throughout the curriculum. In Matiu’s honour, it is entirely appropriate that there are a number of contributions in this Review that have a Māori or Indigenous theme, and we hope future issues will likewise assure such a balance.

year: 2016