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Optimising food production

Over the next 50 years farmers around the world will need to produce more food than has been grown over the past 10,000 years.

Best use from a limited resource

Fertiliser helps farmers produce food efficiently by replenishing the soil. But fertiliser needs to be used responsibly.

Responsible and sustainable nutrient management

The Fertiliser Association invests in research and tools to ensure farm profitability while minimising nutrient losses to the environment.

The Fertiliser Association of New Zealand promotes and encourages responsible and scientifically-based nutrient management.

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New Zealand soil Olsen P levels

The majority of soil data is from pastoral farms, with much smaller numbers of samples from arable or horticulture land use. This is simply a reflection of the relative land areas in these land-use activities.

As a single data set, the national median value of Olsen P showed some fluctuations over time, but little change, with a small increase across the overall time period.

The graphs are reporting median levels of Olsen P, and (in grey) the 25th to 75th percentile range.


Figure 1: Time series of the national median value of Olsen P across all farm and soil types and regions.


Olsen P levels by farm type

We have analysed the data for individual land uses.

Land use categories such as horticulture or orchard cover a wide range of crops with differing nutrient needs. This means that the results from orchard and horticulture land uses show a very wide range of Olsen P results (Figures 2 and 3).



Figure 2: Time series of the national median value of Olsen P across all soil types for horticultural properties.


Figure 3: Time series of the national median value of Olsen P across all soil types for orchards.


Figure 4: Time series of the national median value of Olsen P across all soil types for arable and fodder crop farms.


The bulk of the data reflects tests from pastoral soils (dairy and dry stock farming). The national median values across all soil types are at the high end of target soil Olsen P values for dairy farms on Ash or Sedimentary soils, (20-40, with 30-40 for high producing farms) shown in Figure 5.

The median value for drystock farms across all soil types, is trending toward the middle of target soil Olsen P values for Ash or Sedimentary soils, (20-30), shown in Figure 6. There is some variability attributable to differences in soil type and production intensity.


Figure 5: Time series of the national median value of Olsen P across all soil types for dairy farms.


Figure 6: Time series of the national median value of Olsen P across all soil types for dry stock farms.


Olsen P levels by soil type

When broken down to specific soil types, the higher Olsen P target ranges for Pumice and Organic soils are reflected in the results for those soils (Figures 7 to 10 respectively).


Figure 7: Time series of the national median value of Olsen P across all farm types for Ash soil.


Figure 8: Time series of the national median value of Olsen P across all farm types for Sedimentary soil.


Figure 9: Time series of the national median value of Olsen P across all farm types for Pumice soil.


Figure 10: Time series of the national median value of Olsen P across all farm types for Peat soil.


Variations to the target range

Figures 11 to 18 include the target range for the optimum pasture response.

The target ranges apply to representative farm systems across a combination of farm and soil types. While the vast majority of soil sample results fall within the target range, there remains a considerable 'scatter' of results above and below this range.

Where Olsen P values exceed the target range for the particular farm production system, steps should be taken to understand the circumstances and best ways to ensure any excessive phosphorus use is reduced.

Dairy

Where milksolids production is near the average for the supply area, best economic return is provided by maintenance of soil Olsen P levels in the target range for near maximum pasture production (20-30 for Ash and Sedimentary soils, 35-45 for Pumice and Peat soils).

If milksolids production is in the top 25% for the supply area, or it is intended to increase to this level, increasing soil Olsen P to 30-40 for Ash and Sedimentary soils and to 45-55 for Pumice and Peat soils, may be justified where a response in pasture production is obtained.

Figure 11: Yearly time series of the median level of Olsen P across Ash soils for Dairy farms nationally.

Figure 12: Yearly time series of the median level of Olsen P across Sedimentary soils for Dairy Farms nationally.

Figure 13: Yearly time series of the median level of Olsen P across Pumice soils for Dairy farms nationally.

Figure 14: Yearly time series of the median level of Olsen P across Peat soils for Dairy Farms nationally.


Drystock

On most sheep and beef farms economically optimal soil fertility will be achieved at soil test results below the target soil test range, which provides for near-maximum pasture production (20-30 for Ash and Sedimentary soils, 35-45 for Pumice and Peat soils).


Figure 15: Yearly time series of the median level of Olsen P across Ash soils for Drystock farms, nationally.

Figure 16: Yearly time series of the median level of Olsen P across Sediment soils for Drystock farms, nationally.

Figure 17: Yearly time series of the median level of Olsen P across Pumice soils for Drystock farms, nationally.

Figure 18: Yearly time series of the median level of Olsen P across Peat soils for Drystock farms, nationally.


Arable and Fodder Crops

Figure 19: Yearly time series of the median level of Olsen P across Ash soils for Arable and Fodder Crop farms, nationally.

Figure 20: Yearly time series of the median level of Olsen P across Sedimentary soils for Arable and Fodder Crop farms, nationally.

Figure 21: Yearly time series of the median level of Olsen P across Pumice soils for Arable and Fodder Crop farms, nationally.

Figure 22: Yearly time series of the median level of Olsen P across Peat soils for Arable and Fodder Crop farms, nationally.


Horticulture

Figure 23: Yearly time series of the median level of Olsen P across Ash soils for Horticulture properties, nationally.

Figure 24: Yearly time series of the median level of Olsen P across Sedimentary soils for Horticulture properties, nationally.

Figure 25: Yearly time series of the median level of Olsen P across Pumice soils for Horticulture properties, nationally.

Figure 26: Yearly time series of the median level of Olsen P across Peat soils for Horticulture properties, nationally.


Orchard

Figure 26: Yearly time series of the median level of Olsen P across Ash soils for Orchards, nationally.

Figure 28: Yearly time series of the median level of Olsen P across Sediment soils for Orchards, nationally.

Figure 29: Yearly time series of the median level of Olsen P across Pumice soils for Orchards, nationally.

Figure 30: Yearly time series of the median level of Olsen P across Peat soils for Orchards, nationally.

The Fertiliser Association of New Zealand and Dairy NZ funded development of the Nutrient Management Adviser Certification Programme (NMACP). This industry-wide certification aims to ensure that advisers have the learning, experience and capability to give sound nutrient advice.

Find out more

25 January 2022

Final-year Lincoln University PhD candidate Kirstin Deuss is the 2021 recipient of the NZ Society of Soil Science/Fertiliser Association of NZ Postgraduate Bursary Award.

The award recognises the efforts and present (or likely) contribution to New Zealand soil science arising from a doctorate study. It carries a $5,000 one-year stipend.

Kirstin holds a BSC in Biomedical Science from Victoria University of Wellington and an MSC in Horticultural Science from the Technical University of Munich, Free University of Bozen (Italy) and the University of Bologna.

Her postgraduate research has seen her lead a long-term field study on soil and catchment hydrology in Southland. The findings will help understand the role mole and tile drains play in Southland’s unique landscape.

“I’m thrilled to have been selected as the recipient of the NZSSS Fertiliser Association Postgraduate Bursary, it is an honour that I will cherish for the rest of my career,” says Kirstin. “I love working with soils and my career objective is to apply my field, research and management skills towards supporting the sustainable management of New Zealand’s soil resources.”

“My PhD has been challenging but also so rewarding, and this award is a real confidence boost as I prepare to start my new career at Manaaki Whenua Landcare Research in February. I wouldn't be where I am without the support of my many great mentors, friends and colleagues, who have given me so much of their time and energy to help turn ideas into reality and put it all into the written word!

 “It's truly been the best experience of my life and I am really looking forward to where it is going to take me.”

 Kirstin was nominated by Peter Almond, Associate Professor, Department of Soil and Physical Sciences at Lincoln University. He described her to the judging panel as a “highly adept scientist capable of complex quantitative analysis of soil-hydrological systems”.

“I think she is a deserving recipient.  The prestige of the award would further her goal of securing a position working professionally in soil science in New Zealand so that she can contribute to environmental sustainability of our primary industries.”

Fertiliser Association chief executive Vera Power described Kirstin’s research as “hugely important”.

“The more we can understand what’s happening in our soils and catchments, the better placed our primary sector will be to improve farm management, all while protecting the environment.”  

24 November 2021

FANZ has made a submission to the Ministry for the Environment on Te hau mārohi ki anamata - Transitioning to a low-emissions and climate-resilient future

The primary sector has a key role to play in helping achieve global reductions in greenhouse gas emissions while maintaining food security. This requires low-emission production systems, with increased efficiencies and the use of new mitigation technologies. 

Investment in the development and adoption of new technologies requires a clear regulatory pathway to market. We will need to work internationally with trading nations and also locally with existing qualified networks within the agricultural community for the extension and adoption of new mitigations.  

You can read our submission in full here.


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