title: An investigation into the process of dealumination in soils of the Auckland, Bay of Plenty and Waikato regions of New Zealand

authors: Taylor, Matthew D.

subjects: accelerated weathering

abstract: Dealumination is a term used to describe an increase in the concentration of acid extractable Al as a result of accelerated weathering or chemical attack of primary crystalline and short-range order aluminosilicates. Two speciﬁc mechanisms have been proposed: (1) partial dissolution of clay minerals by local areas of high acidity associated with fertiliser granules; (2) surface complexation and extraction by the ﬂuoride and residual hydroﬂuoric acid present in phosphate fertilisers. This process has been observed in State of the Environment data from the Waikato region, New Zealand, for farmed soils (which receive substantial inputs of phosphate fertilisers) but not for background soils (which are unfertilised). Additional data, including results from XRF analysis for total Al on the original Waikato region samples, acid extractable Al from two neighbouring regions, Auckland and Bay of Plenty, and trends in the data at sites resampled 5 years apart are reported in this work. Retrospective analysis of the Waikato samples by XRF for total Al showed that there was no signiﬁcant difference between farmed and background soils (whereas the increase in acid extractable Al was signiﬁcant, pb0.0001), indicating total Al concentrations were not increasing in farmed soils but the form of it was changing. In farmed soils, proportionately more Al is becoming acidextractable over time. Acid extractable Al results were consistent with dealumination occurring in all 3 regions (pb0.015 to b0.0001) and signiﬁcant (pb0.0001) increases were seen in farmed soils compared to background ones over 5 years, with a mean increase in acid extractable Al of about 1000 mg/kg/year. The actual mechanisms of dealumination and associated soil processes need to be veriﬁed, and the relative importance of possible causative factors delineated (two possible causes are high localised acidity around fertiliser granules, and high annual loadings of F). Whatever the causes, the effects of this process on soil properties and implications to soil management need to be ascertained

text: An investigation into the process of dealumination in soils of the Auckland, Bay of Plenty and Waikato regions of New Zealand Dealumination is a term used to describe an increase in the concentration of acid extractable Al as a result of accelerated weathering or chemical attack of primary crystalline and short-range order aluminosilicates. Two speciﬁc mechanisms have been proposed: (1) partial dissolution of clay minerals by local areas of high acidity associated with fertiliser granules; (2) surface complexation and extraction by the ﬂuoride and residual hydroﬂuoric acid present in phosphate fertilisers. This process has been observed in State of the Environment data from the Waikato region, New Zealand, for farmed soils (which receive substantial inputs of phosphate fertilisers) but not for background soils (which are unfertilised). Additional data, including results from XRF analysis for total Al on the original Waikato region samples, acid extractable Al from two neighbouring regions, Auckland and Bay of Plenty, and trends in the data at sites resampled 5 years apart are reported in this work. Retrospective analysis of the Waikato samples by XRF for total Al showed that there was no signiﬁcant difference between farmed and background soils (whereas the increase in acid extractable Al was signiﬁcant, pb0.0001), indicating total Al concentrations were not increasing in farmed soils but the form of it was changing. In farmed soils, proportionately more Al is becoming acidextractable over time. Acid extractable Al results were consistent with dealumination occurring in all 3 regions (pb0.015 to b0.0001) and signiﬁcant (pb0.0001) increases were seen in farmed soils compared to background ones over 5 years, with a mean increase in acid extractable Al of about 1000 mg/kg/year. The actual mechanisms of dealumination and associated soil processes need to be veriﬁed, and the relative importance of possible causative factors delineated (two possible causes are high localised acidity around fertiliser granules, and high annual loadings of F). Whatever the causes, the effects of this process on soil properties and implications to soil management need to be ascertained

year: 2012

title: The effects of reinforcer magnitude in the preceding and upcoming ratios on between-ratio pausing in multiple fixed-ratio schedules

authors: Young, Rachel

subjects: Reinforcer Magnitude

abstract: Experiment 1 examined the effects of reinforcer magnitude in the preceding and upcoming ratios on between-ratio pausing during a range of FR values in a multiple FR FR schedule of reinforcement. Two components which were associated with two different discriminative stimuli were used, where one component was associated with a small reinforcer (1-s) and the other component was associated with a large reinforcer (6-s). The longest between-ratio pauses were found when the upcoming reinforcer was small (S-S and L-S transition) than when the upcoming reinforcer was large (S-L and L-L transition). In addition, consistently longer between-ratio pauses occurred when the preceding reinforcer was large and the upcoming reinforcer was small (L-S transition). Experiment 2 examined the effects of the past reinforcer magnitude on the between-ratio pause when the discriminative stimuli to differentiate the preceding and upcoming reinforcer magnitude was removed, during a range of FR values on a multiple FR FR schedule of reinforcement. When the past reinforcer magnitude had been small and the upcoming reinforcer was small or large (S-S and S-L transition) consistently shorter between-ratio pauses occurred. In comparison, when the past reinforcer had been large and the upcoming reinforcer was small or large (L-L and L-S transition) consistently longer pause durations occurred across the two transitions. Overall and running response rates were analysed in Experiments 1 and 2 and it was found that overall and running response rates consistently decreased as the FR values were increased. Overall, these experiments showed that the preceding and upcoming reinforcer magnitudes have a direct effect on the length of the between-ratio pause where increasing the FR value was observed to consistently increase the length of the between-ratio pause, when also compared across the four transitions (Small-Small, Small-Large, Large-Large, and Large-Small).

text: The effects of reinforcer magnitude in the preceding and upcoming ratios on between-ratio pausing in multiple fixed-ratio schedules Experiment 1 examined the effects of reinforcer magnitude in the preceding and upcoming ratios on between-ratio pausing during a range of FR values in a multiple FR FR schedule of reinforcement. Two components which were associated with two different discriminative stimuli were used, where one component was associated with a small reinforcer (1-s) and the other component was associated with a large reinforcer (6-s). The longest between-ratio pauses were found when the upcoming reinforcer was small (S-S and L-S transition) than when the upcoming reinforcer was large (S-L and L-L transition). In addition, consistently longer between-ratio pauses occurred when the preceding reinforcer was large and the upcoming reinforcer was small (L-S transition). Experiment 2 examined the effects of the past reinforcer magnitude on the between-ratio pause when the discriminative stimuli to differentiate the preceding and upcoming reinforcer magnitude was removed, during a range of FR values on a multiple FR FR schedule of reinforcement. When the past reinforcer magnitude had been small and the upcoming reinforcer was small or large (S-S and S-L transition) consistently shorter between-ratio pauses occurred. In comparison, when the past reinforcer had been large and the upcoming reinforcer was small or large (L-L and L-S transition) consistently longer pause durations occurred across the two transitions. Overall and running response rates were analysed in Experiments 1 and 2 and it was found that overall and running response rates consistently decreased as the FR values were increased. Overall, these experiments showed that the preceding and upcoming reinforcer magnitudes have a direct effect on the length of the between-ratio pause where increasing the FR value was observed to consistently increase the length of the between-ratio pause, when also compared across the four transitions (Small-Small, Small-Large, Large-Large, and Large-Small).

year: 2015

title: Indigenous Peoples and the State - International Perspectives on the Treaty of Waitangi [Book Review]

authors: Te Aho, Linda

abstract: Just over thirty years ago, in the High Court decision Huakina Development Trust v Waikato Valley Authority, Justice Chilwell famously stated: “There can be no doubt that the Treaty is part of the fabric of New Zealand society.” ¹ At a symposium celebrating 30 years of the Huakina decision, Tom Bennion described the judgment as “a marker, a significant new structure sticking out in the legal landscape, indicating the shape of arguments to come.” This collection of work brings together a range of arguments for our time concerning the meaning and importance of the Treaty of Waitangi, shaped by different perspectives on its context and history.

text: Indigenous Peoples and the State - International Perspectives on the Treaty of Waitangi [Book Review] Just over thirty years ago, in the High Court decision Huakina Development Trust v Waikato Valley Authority, Justice Chilwell famously stated: “There can be no doubt that the Treaty is part of the fabric of New Zealand society.” ¹ At a symposium celebrating 30 years of the Huakina decision, Tom Bennion described the judgment as “a marker, a significant new structure sticking out in the legal landscape, indicating the shape of arguments to come.” This collection of work brings together a range of arguments for our time concerning the meaning and importance of the Treaty of Waitangi, shaped by different perspectives on its context and history.

year: 2019