title: Kainui silt loam: how the lepard changed its spots

authors: Lowe, David J.

subjects: Hamilton

abstract: The Kainui silt loam occurs on low rolling hills in the northern part of the Hamilton Basin, and is well expressed in Hamilton City.

text: Kainui silt loam: how the lepard changed its spots The Kainui silt loam occurs on low rolling hills in the northern part of the Hamilton Basin, and is well expressed in Hamilton City.

year: 1991

title: Nitrogen leaching from effluent irrigated pasture

authors: Treweek, Glen

subjects: sewage

abstract: The surface waters of the Taupo region are of high quality and are sensitive to inputs of nitrogen. To reduce the amount of nitrogen discharged to surface water, the Taupo District Council (TDC) has employed a land treatment scheme (LTS), where treated municipal wastewater is irrigated onto ryegrass pasture. To limit the possibility of nitrogen pollution, regulations govern the amount of effluent that TDC may irrigate. This study reports the results from the first year of a five year trial where nitrogen leaching from the Taupo LTS was measured.
To measure nitrogen leaching from the Taupo LTS, 48 intact monolith lysimeters were installed beneath effluent irrigation from two centre pivot irrigators. Four treatments based on nitrogen loading rates were trialled, nominally no-N (0 kg N ha-¹yr-¹), low-N (350 kg N ha-¹yr-¹ or less), mid-N (between 350 and 450 kg N ha-¹yr-¹), and high-N (greater than 450 kg N ha-¹yr-¹). Leachate was collected at least monthly and analysed for total nitrogen (TN), nitrate/nitrite nitrogen (NO₃-N), ammoniacal nitrogen (NH₄-N), dissolved organic nitrogen (DON), and total Kjeldahl nitrogen (TKN). The pasture was removed from the lysimeters to determine dry-matter production and pasture nitrogen concentration to calculate nitrogen uptake.
Effluent irrigation significantly increased pasture growth and nitrogen leaching compared to the un-irrigated treatments (P<0.001). The mean rate of pasture growth from the irrigated treatments was 15,800 ± 1,700 kg DM ha-¹yr-¹, but there were no significant difference between the rate of pasture growth between the irrigated treatments. The pasture of the high-N treatments had a significantly higher nitrogen concentration than the low-N treatments (P<0.001), consequently the high-N treatment removed 390 kg N ha-¹, compared to 310 kg N ha-¹ removed from the mid-N and low-N treatments. On average, the pasture removed 84 % of the nitrogen that was irrigated.
After 12 months, the no-N treatments leached 5 ± 3 kg TN ha-¹, the low-N treatment leached 15 ± 1 kg TN ha-¹, the mid-N treatment leached 17 ± 8 kg TN ha-¹, and the high-N treatment leached 26 ± 4 kg TN ha-¹. The high-N treatments leached significantly more TN than the low-N (P<0.005), but there was no significant difference in TN leached between the high-N and mid-N, or the mid-N and low-N treatments. The TN leached was poorly correlated with the rate of effluent irrigation. TN leached was positively correlated with the volume of water that drained through the soil (R2=0.7). The nitrogen in the leachate of the irrigated treatments comprised on average, 53 % NO₃-N, and 45 % DON, while the leachate of the un-irrigated treatments comprised, on average, 26 % NO₃-N and 72 % DON. NH₄-N accounted for approximately 2% of all nitrogen leached. Most of the NO₃-N leached throughout the year was leached after rain during summer and autumn. The mean concentration of NO₃-N leached from the irrigated treatments was 1.3 g N m-³. The concentration of NO₃-N in the leachate never exceeded Ministry of Health guidelines (11.3 g N m-³). The mean concentration of DON leached from the irrigated treatments was 1.2 g N m-³.
Removing nitrogen in the pasture is the solution to avoid excess nitrogen leaching from the Taupo LTS. There is potential to recover more nitrogen in the pasture by improving the pasture cover and frequency of harvest.

text: Nitrogen leaching from effluent irrigated pasture The surface waters of the Taupo region are of high quality and are sensitive to inputs of nitrogen. To reduce the amount of nitrogen discharged to surface water, the Taupo District Council (TDC) has employed a land treatment scheme (LTS), where treated municipal wastewater is irrigated onto ryegrass pasture. To limit the possibility of nitrogen pollution, regulations govern the amount of effluent that TDC may irrigate. This study reports the results from the first year of a five year trial where nitrogen leaching from the Taupo LTS was measured.
To measure nitrogen leaching from the Taupo LTS, 48 intact monolith lysimeters were installed beneath effluent irrigation from two centre pivot irrigators. Four treatments based on nitrogen loading rates were trialled, nominally no-N (0 kg N ha-¹yr-¹), low-N (350 kg N ha-¹yr-¹ or less), mid-N (between 350 and 450 kg N ha-¹yr-¹), and high-N (greater than 450 kg N ha-¹yr-¹). Leachate was collected at least monthly and analysed for total nitrogen (TN), nitrate/nitrite nitrogen (NO₃-N), ammoniacal nitrogen (NH₄-N), dissolved organic nitrogen (DON), and total Kjeldahl nitrogen (TKN). The pasture was removed from the lysimeters to determine dry-matter production and pasture nitrogen concentration to calculate nitrogen uptake.
Effluent irrigation significantly increased pasture growth and nitrogen leaching compared to the un-irrigated treatments (P<0.001). The mean rate of pasture growth from the irrigated treatments was 15,800 ± 1,700 kg DM ha-¹yr-¹, but there were no significant difference between the rate of pasture growth between the irrigated treatments. The pasture of the high-N treatments had a significantly higher nitrogen concentration than the low-N treatments (P<0.001), consequently the high-N treatment removed 390 kg N ha-¹, compared to 310 kg N ha-¹ removed from the mid-N and low-N treatments. On average, the pasture removed 84 % of the nitrogen that was irrigated.
After 12 months, the no-N treatments leached 5 ± 3 kg TN ha-¹, the low-N treatment leached 15 ± 1 kg TN ha-¹, the mid-N treatment leached 17 ± 8 kg TN ha-¹, and the high-N treatment leached 26 ± 4 kg TN ha-¹. The high-N treatments leached significantly more TN than the low-N (P<0.005), but there was no significant difference in TN leached between the high-N and mid-N, or the mid-N and low-N treatments. The TN leached was poorly correlated with the rate of effluent irrigation. TN leached was positively correlated with the volume of water that drained through the soil (R2=0.7). The nitrogen in the leachate of the irrigated treatments comprised on average, 53 % NO₃-N, and 45 % DON, while the leachate of the un-irrigated treatments comprised, on average, 26 % NO₃-N and 72 % DON. NH₄-N accounted for approximately 2% of all nitrogen leached. Most of the NO₃-N leached throughout the year was leached after rain during summer and autumn. The mean concentration of NO₃-N leached from the irrigated treatments was 1.3 g N m-³. The concentration of NO₃-N in the leachate never exceeded Ministry of Health guidelines (11.3 g N m-³). The mean concentration of DON leached from the irrigated treatments was 1.2 g N m-³.
Removing nitrogen in the pasture is the solution to avoid excess nitrogen leaching from the Taupo LTS. There is potential to recover more nitrogen in the pasture by improving the pasture cover and frequency of harvest.

year: 2011

title: An evaluation of the effectiveness of social equity strategies for Maori students in the School of Science and Technology

authors: Rua, Mohi

subjects: Maori students

abstract: In 1991 the School of Science and Technology (SOSAT) at the University of Waikato
had a very low participation rate of Maori and students from other non-dominant
ethnic groups. This situation was serious enough to concerned the then Dean of the
School and strategies were developed to change this situation. Four major strategies
are used to encourage, support and retain Maori students to successfully pursue and
complete a degree in Science. They are: the Te Putahi o te Manawa programme - a
mentoring programme; a scholarship and grant writing strategy (in particular
assistance with Tuapapa Putaiao Maori Fellowships(TPMFs) administered by FRST);
school visits; and field trips with secondary schools in the Waikato region that have a
high proportion of Maori students. The Maori & Psychology Research Unit (MPRU) was contracted by Gary Bramley of
the Equity Office of the SOSAT to conduct this evaluation. Evaluative information was gathered through administering questionnaires,
completing key informant interviews, and completing focus group interviews. In this evaluation we sought to determine the effectiveness of the social equity
strategies for Maori students in the SOSAT at the University of Waikato.

text: An evaluation of the effectiveness of social equity strategies for Maori students in the School of Science and Technology In 1991 the School of Science and Technology (SOSAT) at the University of Waikato
had a very low participation rate of Maori and students from other non-dominant
ethnic groups. This situation was serious enough to concerned the then Dean of the
School and strategies were developed to change this situation. Four major strategies
are used to encourage, support and retain Maori students to successfully pursue and
complete a degree in Science. They are: the Te Putahi o te Manawa programme - a
mentoring programme; a scholarship and grant writing strategy (in particular
assistance with Tuapapa Putaiao Maori Fellowships(TPMFs) administered by FRST);
school visits; and field trips with secondary schools in the Waikato region that have a
high proportion of Maori students. The Maori & Psychology Research Unit (MPRU) was contracted by Gary Bramley of
the Equity Office of the SOSAT to conduct this evaluation. Evaluative information was gathered through administering questionnaires,
completing key informant interviews, and completing focus group interviews. In this evaluation we sought to determine the effectiveness of the social equity
strategies for Maori students in the SOSAT at the University of Waikato.

year: 1999-11-11