title: The effect of irrigation on cadmium, uranium, and phosphorus contents in agricultural soils

authors: Salmanzadeh, Mahdiyeh

subjects: Cadmium

abstract: Cadmium (Cd) is a toxic metal which has accumulated in New Zealand agricultural soils due to phosphate fertilizer application. Understanding the contribution of plant uptake or leaching of Cd to observed Cd losses from soil is important. The concentration and distribution of Cd in irrigated and unirrigated soils with the same phosphate fertilizer history were investigated. Twenty-two pairs of soil samples from four depths (0–0.1, 0.1–0.2, 0.2–0.3 and 0.3–0.4 m) were taken from irrigated and unirrigated areas in the same field on dairy farms in three regions of New Zealand. The mean concentration of Cd at depths of 0–0.1 m and 0.1–0.2 m, as well as the cumulative masses of Cd (0–0.2, 0–0.3 and 0–0.4 m) in unirrigated soils were significantly higher (P < 0.05) than in irrigated soils. The concentration of phosphorus (P) at all depths (except for 0.2–0.3 m), as well as the cumulative mass of P in all depths of unirrigated soils, was also significantly higher (P < 0.05) than irrigated soils. However, no significant difference was detected in the concentrations of uranium (U) between irrigated and unirrigated soils. Irrigation induced a ∼7% Cd loss from topsoil (0–0.1 m), with the average rate of Cd loss from the top 0.1 m (due to irrigation) being 2.3 g ha⁻¹ yr⁻¹. This study therefore confirms that irrigation can enhance Cd mobilization, however Cd is mainly adsorbed to the surface soil.

text: The effect of irrigation on cadmium, uranium, and phosphorus contents in agricultural soils Cadmium (Cd) is a toxic metal which has accumulated in New Zealand agricultural soils due to phosphate fertilizer application. Understanding the contribution of plant uptake or leaching of Cd to observed Cd losses from soil is important. The concentration and distribution of Cd in irrigated and unirrigated soils with the same phosphate fertilizer history were investigated. Twenty-two pairs of soil samples from four depths (0–0.1, 0.1–0.2, 0.2–0.3 and 0.3–0.4 m) were taken from irrigated and unirrigated areas in the same field on dairy farms in three regions of New Zealand. The mean concentration of Cd at depths of 0–0.1 m and 0.1–0.2 m, as well as the cumulative masses of Cd (0–0.2, 0–0.3 and 0–0.4 m) in unirrigated soils were significantly higher (P < 0.05) than in irrigated soils. The concentration of phosphorus (P) at all depths (except for 0.2–0.3 m), as well as the cumulative mass of P in all depths of unirrigated soils, was also significantly higher (P < 0.05) than irrigated soils. However, no significant difference was detected in the concentrations of uranium (U) between irrigated and unirrigated soils. Irrigation induced a ∼7% Cd loss from topsoil (0–0.1 m), with the average rate of Cd loss from the top 0.1 m (due to irrigation) being 2.3 g ha⁻¹ yr⁻¹. This study therefore confirms that irrigation can enhance Cd mobilization, however Cd is mainly adsorbed to the surface soil.

year: 2017

title: Seeding strategies for semantic disambiguation

authors: Hinze, Annika

subjects: computer science

abstract: Semantic disambiguation determines the meaning of words and phrases in a text, for which we use an automatically-generated Concept-in-Context (CiC) network. Words and phrases rarely belong to a single concept; disambiguation in Capisco relies on interplay between words that are in close vicinity in the text. Starting the disambiguation is a seeding process, that identifies the first concepts, which then form the context for further disambiguation steps. This paper introduces the seeding algorithm and explores seeding strategies for identifying these initial concepts in text volumes, such as books, that are stored in a digital library.

text: Seeding strategies for semantic disambiguation Semantic disambiguation determines the meaning of words and phrases in a text, for which we use an automatically-generated Concept-in-Context (CiC) network. Words and phrases rarely belong to a single concept; disambiguation in Capisco relies on interplay between words that are in close vicinity in the text. Starting the disambiguation is a seeding process, that identifies the first concepts, which then form the context for further disambiguation steps. This paper introduces the seeding algorithm and explores seeding strategies for identifying these initial concepts in text volumes, such as books, that are stored in a digital library.

year: 2018

title: Waikirikiri Marae: Shared experiences of the wharemate

authors: Rua, Hare

subjects: Māori

abstract: In Te Urewera, wharemate (shelters in which the deceased receive their final farewells) have traditionally been temporary structures. In the 1980s, a new practice was introduced in the Ruātoki valley with the erection of permanent wharemate facilities. One was erected at Waikirikiri marae (tribal meeting grounds and associated buildings) in 1989. Knowledge and discussion regarding wharemate at Waikirikiri marae have changed over the years, and a whole generation has not been fortunate enough to experience tikanga (correct procedures, customary practices) that prevailed prior to the introduction of the permanent wharemate building that is there today. These changes are recorded in this paper through the shared stories of three kaumātua (elders) from Waikirikiri.

This paper is a summary of Hare Rua’s thesis study, the data for which was collected in 2009. This work forms part of the Tangi Research Programme, a collaboration between the School of Māori and Pacific Development and the Māori and Psychology Research Unit at The University of Waikato, Hamilton, New Zealand.

text: Waikirikiri Marae: Shared experiences of the wharemate In Te Urewera, wharemate (shelters in which the deceased receive their final farewells) have traditionally been temporary structures. In the 1980s, a new practice was introduced in the Ruātoki valley with the erection of permanent wharemate facilities. One was erected at Waikirikiri marae (tribal meeting grounds and associated buildings) in 1989. Knowledge and discussion regarding wharemate at Waikirikiri marae have changed over the years, and a whole generation has not been fortunate enough to experience tikanga (correct procedures, customary practices) that prevailed prior to the introduction of the permanent wharemate building that is there today. These changes are recorded in this paper through the shared stories of three kaumātua (elders) from Waikirikiri.

This paper is a summary of Hare Rua’s thesis study, the data for which was collected in 2009. This work forms part of the Tangi Research Programme, a collaboration between the School of Māori and Pacific Development and the Māori and Psychology Research Unit at The University of Waikato, Hamilton, New Zealand.

year: 2010