Quantifying contaminant losses to water from pastoral landuses in New Zealand I. Development of a spatial framework for assessing losses at a farm scale

Author(s):  
Ross Monaghan ◽  
Andrew Manderson ◽  
Les Basher ◽  
Chris Smith ◽  
David Burger ◽  
...  
Soil Research ◽  
2012 ◽  
Vol 50 (3) ◽  
pp. 188 ◽  
Author(s):  
Iris Vogeler ◽  
Pierre Beukes ◽  
Alvaro Romera ◽  
Rogerio Cichota

Nitrous oxide (N2O) emissions from agriculture are generally estimated using default IPCC emission factors (EFs) despite the large variation in measured EFs. We used a classification and regression tree (CART) analysis to segregate measured EFs from direct emissions from urine patches and fertiliser and effluent applications, based on temporal and site-specific factors. These segregated EFs were linked to simulations from the DairyNZ Whole Farm Model to obtain N2O emissions for a typical pasture-based dairy farm in New Zealand. The N2O emissions from urine patches, dung pads, and fertiliser and effluent application, as well as from indirect sources, were aggregated to obtain total N2O emissions for the farm-scale. The results, based on segregated EFs, were compared with those obtained using New Zealand-specific EFs. On-farm N2O emissions based on these segregated EFs were 5% lower than those based on New Zealand-specific EFs. Improved farm management by avoiding grazing, effluent, and N fertiliser application during periods of high risk for N2O emissions, or by the use of mitigation technologies such as nitrification inhibitors, could reduce annual farm scale N2O emissions.


2006 ◽  
Vol 59 ◽  
pp. 312-316 ◽  
Author(s):  
T.A. White ◽  
P.J. Gerard

Clover root weevil (Sitona lepidus CRW) is a major New Zealand pasture pest This study used computer simulation and decision support modelling to simulate CRW herbivory estimate the longterm consequences on clover abundance pasture production and quality and financial implications to a typical sheep and beef farmer Three farm scenarios were explored the absence of CRW and the presence of CRW with and without additional nitrogen (N) For a hypothetical 325 ha Waikato sheep and beef farm CRW decreased mean clover abundance from 21 to 13 pasture production from 9200 to 7900 kg DM/ha/year pasture quality from 105 to 102 MJME/kg DM and N fixation from 60 to 42 kg N/ha/year This resulted in a 16 reduction in the annual gross margin However assuming current prices and costs and that an N response could be consistently achieved urea could be used to replace the reduction in N fixation without affecting profits


2004 ◽  
Vol 57 ◽  
pp. 304-309 ◽  
Author(s):  
S. Hardwick

In autumn 1998 a farm scale replicated field trial was established in Waikato New Zealand to measure the productivity of combinations of old and new ryegrass and white clover cultivars Colonisation in the first two years of the trial by Costelytra zealandica Heteronychus arator Naupactus leucoloma and Sitona lepidus was monitored By the end of winter 2000 no difference in densities of any of the pest species monitored could be attributed to cultivar treatments However dispersal behaviour and soil type did have a significant effect on pest densities Naupactus leucoloma which disperses by walking was found in greatest densities on the edges of the trial Costelytra zealandica which disperses by flying was initially aggregated in paddocks with shelterbelts Heavy infestations of H arator which also disperses by flying were associated with good soil drainage Sitona lepidus which disperses by flying was evenly distributed across the trial


2021 ◽  
Vol 187 ◽  
pp. 103007
Author(s):  
Estelle J. Dominati ◽  
Alec D. Mackay ◽  
John M. Rendel ◽  
Andrew Wall ◽  
David A. Norton ◽  
...  

2021 ◽  
Author(s):  
◽  
Alicia I. Taylor

<p>Degradation of water quality is a major issue in New Zealand, to which the loss of nitrogen, phosphorus and sediment from agriculture into waterways contributes significantly. To predict and manage diffuse pollution from intensive agriculture it is vital that models are able to spatially map the sources, flows and sinks of nutrients in the landscape and spatially target mitigations. This study investigates the application of one such model, the Land Utilisation Capability Indicator (LUCI). Used in conjunction with OVERSEER, LUCI is a powerful tool to support farm scale land management decision-making.  LUCI includes soil, topography and landcover datasets in its analysis. This thesis examines how the quality and resolution of each dataset affects LUCI’s output. Six different case studies are examined, across a range of New Zealand farming systems. This is the most comprehensive study, to date, of LUCI’s sensitivity to input datasets.  The results suggest that LUCI nutrient loading estimates are primarily sensitive to soil order, and therefore to changes in order classifications. Utilising different soil datasets in the LUCI model resulted in varying nutrient load predictions. This sensitivity is primarily attributed to the differing hydraulic and phosphorus retention capabilities of the respective soil orders. To test the sensitivity of LUCI to digital elevation model (DEM) resolution, multiple DEMs with varying spatial and vertical resolution were tested. These results strongly indicate that particularly fine resolution DEMs are required to accurately model flat landscapes.  It was recognised that LUCI was not using all of the relevant data available in Landcare Research’s S-Map database. LUCI was modified to use more of this information, and alternative methods of incorporating sibling level data in both LUCI and OVERSEER were investigated. Finally, avenues for future development are suggested. Overall, this thesis highlights the potential LUCI has to play a key role in farm scale environmental management.</p>


2021 ◽  
Author(s):  
◽  
Alicia I. Taylor

<p>Degradation of water quality is a major issue in New Zealand, to which the loss of nitrogen, phosphorus and sediment from agriculture into waterways contributes significantly. To predict and manage diffuse pollution from intensive agriculture it is vital that models are able to spatially map the sources, flows and sinks of nutrients in the landscape and spatially target mitigations. This study investigates the application of one such model, the Land Utilisation Capability Indicator (LUCI). Used in conjunction with OVERSEER, LUCI is a powerful tool to support farm scale land management decision-making.  LUCI includes soil, topography and landcover datasets in its analysis. This thesis examines how the quality and resolution of each dataset affects LUCI’s output. Six different case studies are examined, across a range of New Zealand farming systems. This is the most comprehensive study, to date, of LUCI’s sensitivity to input datasets.  The results suggest that LUCI nutrient loading estimates are primarily sensitive to soil order, and therefore to changes in order classifications. Utilising different soil datasets in the LUCI model resulted in varying nutrient load predictions. This sensitivity is primarily attributed to the differing hydraulic and phosphorus retention capabilities of the respective soil orders. To test the sensitivity of LUCI to digital elevation model (DEM) resolution, multiple DEMs with varying spatial and vertical resolution were tested. These results strongly indicate that particularly fine resolution DEMs are required to accurately model flat landscapes.  It was recognised that LUCI was not using all of the relevant data available in Landcare Research’s S-Map database. LUCI was modified to use more of this information, and alternative methods of incorporating sibling level data in both LUCI and OVERSEER were investigated. Finally, avenues for future development are suggested. Overall, this thesis highlights the potential LUCI has to play a key role in farm scale environmental management.</p>


1999 ◽  
Vol 190 ◽  
pp. 563-566
Author(s):  
J. D. Pritchard ◽  
W. Tobin ◽  
J. V. Clausen ◽  
E. F. Guinan ◽  
E. L. Fitzpatrick ◽  
...  

Our collaboration involves groups in Denmark, the U.S.A. Spain and of course New Zealand. Combining ground-based and satellite (IUEandHST) observations we aim to determine accurate and precise stellar fundamental parameters for the components of Magellanic Cloud Eclipsing Binaries as well as the distances to these systems and hence the parent galaxies themselves. This poster presents our latest progress.


Author(s):  
Ronald S. Weinstein ◽  
N. Scott McNutt

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.


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