NZQA Expiring unit standard
Title
20957 version 2
Page 1 of 4
Demonstrate knowledge of efficiency statistics, calculate KPIs and determine irrigation requirements
Level
Purpose
4 Credits 6
People credited with this unit standard are able to: demonstrate knowledge of population sampling techniques used in irrigation; perform statistical calculations relevant to irrigation; calculate key performance indicators (KPIs) of irrigation systems; and determine irrigation requirements for a specified situation.
Classification Water Industry > Irrigation
Available grade Achieved
Explanatory notes
1 Legislation relevant to this unit standard includes but is not limited to the Health and
Safety in Employment Act 1992.
2 Definition organisational procedures
– the verbal and written instructions to staff on irrigation system performance.
Outcome 1
This unit standard is expiring
Range population sampling techniques
– randomised, stratified, targeted.
Evidence requirements
1.1 Population sampling techniques used in irrigation are described in terms of the procedures used, sample size, and validity.
1.2 A specified sampling technique is described in terms of its applications for irrigation system types.
Range irrigation systems
– centre pivot, linear move, traveling gun, traveling linear boom, traveling rotating boom, sprayline, fixed sprinkler, drip-micro, surface.
Primary Industry Training Organisation
SSB Code 101558

New Zealand Qualifications Authority 2020
This unit standard is expiring
New Zealand Qualifications Aut

NZQA Expiring unit standard
1.3
20957 version 2
Page 2 of 4
A specified sampling technique is described in terms of its applications for a particular situation, its advantages, and limitations.
Outcome 2
Perform statistical calculations relevant to irrigation.
Evidence requirements
2.1 Calculations are performed for specified irrigation systems.
Range mean (arithmetic, geomean, moving average), variance, coefficient of variation, standard deviation, statistical average (root sum of squares).
Outcome 3
Calculate KPIs of irrigation systems.
Evidence requirements
3.1 Water use efficiency is defined and determined for a specified irrigation system.
Range irrigation systems – centre pivot, linear move, traveling gun, traveling linear boom, traveling rotating boom, sprayline, fixed sprinkler, drip-micro, surface; application uniformity
– distribution uniformity (DU), coefficient of uniformity (CU), emission uniformity (EU).
3.2 Water use peformance indicators are defined and determined for a specified irrigation system.
3.3
Range
This unit standard is irrigation, application efficiency, distribution efficiency, headwork expiring
Other performance indicators are defined and determined for a specified irrigation system.
Range energy
– system rating, energy per unit volume, energy per unit area; labour; capital cost, operating cost; effectiveness
– productivity, returns; environment
– average irrigation system efficiency, deep or through drainage, runoff, travel time, irrigation duration.
Outcome 4
Determine irrigation requirements for a specified situation.
Evidence requirements
Primary Industry Training Organisation
SSB Code 101558

New Zealand Qualifications Authority 2020
This unit standard is expiring
New Zealand Qualifications Aut

4.3
4.4
4.5
NZQA Expiring unit standard
4.1
20957 version 2
Daily water use is estimated for an area of crop in a given situation.
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Range growth stage, potential evapo-transpiration rate, actual evapotranspiration rate, crop type, plant water stress.
4.2 Readily available soil moisture is estimated for a given soil and crop.
Range soil type, root depth, wetted depth, crop type, critical deficit, trigger point.
Irrigation return interval is calculated.
Irrigation scheduling coefficient is calculated for a given system uniformity.
Volume of water to be applied to a given area at a specific application rate, the amount of water stored in the root zone (and/or soil profile), and the amount of drainage for a given system uniformity are calculated.
Range volume taken, take rate, irrigation duration, machine speed (if applicable).
Replacement information This unit standard has been replaced by unit standard
28926 and unit standard 28935
This unit standard is expiring. Assessment against the standard must take place by the last date for assessment set out below.
Process
Registration
Review
1
2 expiring 31 December 2020
31 December 2020
Consent and Moderation Requirements (CMR) reference 0179
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do
.
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by
NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and which are assessing against unit standards must engage with the moderation system that applies to those standards.
Primary Industry Training Organisation
SSB Code 101558

New Zealand Qualifications Authority 2020
This unit standard is expiring
New Zealand Qualifications Aut

NZQA Expiring unit standard 20957 version 2
Page 4 of 4
Requirements for consent to assess and an outline of the moderation system that applies to this standard are outlined in the Consent and Moderation Requirements (CMR). The
CMR also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements.
This unit standard is expiring
Primary Industry Training Organisation
SSB Code 101558

New Zealand Qualifications Authority 2020
This unit standard is expiring
New Zealand Qualifications Aut