NCEA Level 3 Agricultural and Horticultural Science (90653) 2012 Assessment Schedule

NCEA Level 3 Agricultural and Horticultural Science (90653) 2012 — page 1 of 5

Assessment Schedule – 2012 Agricultural and Horticultural Science: Analyse a primary production environmental issue (90653) Evidence Statement

Evidence for Achievement Evidence for Achievement Evidence for Achievement with Merit with Excellence  TWO negative environmental  TWO negative environmental  TWO negative environmental impacts are explained. impacts are explained in detail impacts are explained in detail (evidence of data or additional (evidence of data or additional AND understanding). understanding).  ONE economic OR ONE social  ONE economic OR ONE social  ONE economic OR ONE social implication is explained. implication is explained (evidence implication is explained (evidence AND of data or additional of data or additional understanding). understanding).  TWO “realistic” courses of action are identified, valid strengths and  TWO “realistic” courses of action  TWO “realistic” courses of action weaknesses are explained, and are identified, valid strengths and are identified, valid strengths and ONE is recommended. weaknesses are explained, and weaknesses are explained in ONE course of action is justified. detail (evidence of data or additional understanding), and ONE course of action is justified.

Judgement Statement

Achievement Achievement with Merit Achievement with Excellence A M E

Appendix: Examples of possible answers

Selected option: The breakdown of soil stability in agricultural / horticultural systems Part (a) Environmental, economic, and social implications

Negative environmental implications

 Increase in soil surface erosion / loss of topsoil during heavy rain, as the finer particles are more easily “washed” away.

 Increased loss of topsoil / wind erosion of soil, due to the loss of a crumb structure and increase in fine particles that are more susceptible to wind erosion.  Increased volumes of sediment in rivers and streams, due to more soil being carried in surface run-off.  Under heavy rainfall, up to 10 percent of erosion-prone land under pasture can be lost.  Winter pugging has been shown to reduce annual pasture production by 35% in a single year, and by 53% after two years of the soil sustaining pugging damage.

Negative economic implications

 Loss of yield, and hence income, due to the breakdown of soil structure / stability. Trials in Canterbury show yield / income losses of 18%–62% associated with the combined effects of topsoil loss and structural breakdown.  Increased costs associated with increased fertiliser and cultivation required by degraded soils when cropping them.

 Costs associated with constantly dredging river channels / bolstering stop banks to address the silting-up of rivers.  Flooding is estimated to have cost New Zealand insurers $247 million between 1995 and 2004.  Annual costs associated with hill country erosion are estimated at $100 to $150 million. NCEA Level 3 Agricultural and Horticultural Science (90653) 2012 — page 2 of 5

 Following the Bay of Plenty and Manawatu floods in 1995, central government provided approximately $198 million to compensate farmers for lost production, to rebuild roads and bridges, and for rates relief.

Social implications

 Increased sediment in run-off causes silting-up of streams / rivers downstream, affecting recreational activities (eg fishing) as well as other uses of water (eg for drinking).  Other social effects, such as a loss in farmer confidence, visual effects, etc.

Part (b) Evaluation of potential courses of action Intensive agricultural (livestock) production systems 1. Remove stock from pasture and put on a stand-off pad or feed pad. Strengths:

 Further damage to the pasture is prevented, allowing greater future growth / production than if pugging had occurred.  Stock remain on the farm, allowing for ease of management.

 Risk of topsoil erosion / run-off into streams is minimised.  Soil structure is not damaged. Weaknesses:  High capital costs involved in building a pad.

 Need to transport feed / silage to the stock while they are on the pad, or allow stock back onto pasture for a period of time daily to feed, minimising damage.  Need to deal with the effluent of the stock while they are on the pad.  Animal health issues may arise if stock remain on a pad for a long period of time.

2. Spread stock over a larger area. Strengths:

 Damage to pasture / soil is reduced, as treading density / intensity is less.

 No need to remove stock from pasture / farm, thus no extra management is required. Weaknesses:  “Saved” pasture will be eaten at a greater rate, possibly causing feed supply problems later in the season (especially with prolonged periods of hot weather).

 Some damage to soils / pasture is still likely to occur, affecting soil structure / pasture growth.  An increased area of the farm is affected.

 Extra management required by animals being spread over a larger area / increased number of paddocks – especially with dairy farms.

Intensive plant production / cropping systems

1. Use minimum tillage techniques / technologies (eg direct drilling in combination with the use of herbicides to remove vegetation competing with plant crops. Strengths:  Less physical disturbance to soil, reducing the potential for soil structural damage.  Less risk of soil erosion (water and wind), as soil particles are less exposed.

 Decreased costs of fuel etc, as fewer “passes” done by tractors during seed bed establishment / sowing.  Soil biota (worms, etc) allowed to exist without getting “chopped up”. Weaknesses:

 Some crops / stubbles are difficult to sow into; some crops require a fine seed bed for optimum germination.

 Use of herbicides may involve chemicals that build up / accumulate in the soil / environment.

2. Plant “cover” or “green manure” crops following the harvest of each “main” crop. Strengths:

 Provides time and organic matter to encourage soil organisms to begin to improve / repair soil structure.  Addition of organic matter helps “condition” the soil, making it a better medium for plant growth. NCEA Level 3 Agricultural and Horticultural Science (90653) 2012 — page 3 of 5

Weaknesses:  Extra costs involved in plating a “cover” crop.  No income being generated off the land at this time.

3. Continue to use conventional cultivation techniques (ie using ploughs, rotary hoes, etc) when cultivating soil prior to planting. Strengths:  Ability to establish the fine seed beds that some crops prefer.  Farmers and contractors have existing skills, machinery, and experience in this form of pre-planting management.

Weaknesses:  Continued breakdown of soil stability – especially if cultivating soils outside optimum moisture content, or if using rotary hoes and similar “high impact” machinery.

 Higher fuel / energy costs associated with most conventional cultivation programmes.

 More limited by wet soils / wet weather – unable to cultivate.

Extensive Hill Country Agricultural Systems 1. Plant forestry tree species. Strengths:  Using forestry to protect erosion-prone hill country can reduce the damage from 10% of a catchment to 1%.  Can provide a revenue from that land in future years if carefully managed.  Carbon credits can be received, providing another income source for often less productive land. Weaknesses:  Loss of productive land, reducing potential carrying capacity.  Cost associated with the management of trees, weeds, pest control, etc.

2. Retire classes VI to VIII land and allow those areas to regenerate into native species. Strengths:  Regenerating slopes protect erosion-prone hill country, reducing the potential damage from 10% of a catchment to 1%.  May provide some revenue via carbon farming and credits.

 Biodiversity / bird life / native species are allowed to return.  Improved water quality in the catchment (increased clarity, etc). Weaknesses:  Loss of productive land, reducing potential carrying capacity.  Costs associated with the management of fencing, weeds, pest control, etc can be considerable. Fencing alone is around $10 000 / km in many terrains for fully sheep-proofed grazing land. NCEA Level 3 Agricultural and Horticultural Science (90653) 2012 — page 4 of 5

Selected option: The use of water in agricultural / horticultural systems

Part (a) Environmental, economic, and social implications

Negative environmental implications  Decreased river and stream levels.  Increased water temperatures.  Less dilution of contaminants, eg effluent.  Greater potential for leaching of soil nutrients.  Lowering of water tables and aquifers.

Economic implications

 Electricity costs for sprinkler-type irrigators are typically $30 000 / year for a 100 ha property.  At 2010 costs, based on 100 hectares, a capital outlay of around $300 000 would be required to install the most efficient medium-to-long-term system involving central pivot water application.

Social implications  The level of aquifers under the ground can drop, due to water being extracted, often meaning longer-term users need to re-drill their bores to access the lower water table.  Rivers have less flow and recreational users (boaties, fishermen, etc) are negatively affected – eg the Selwyn River was once considered one of the country’s top trout rivers, with spawning runs in excess of 40 000 trout. A recent count of trout during spawning counted 87 trout.  A gross income 2.2–6 times higher can be generated.

Part (b) Evaluation of potential courses of action 1. Restrict water usage to a level where minimum flow levels (that have been established according to acceptable environmental impact by regional councils) are not reached. Allocation is on the basis of consents and a “first come, first served” principle. Strengths:  Current usage, practices, and economic benefits are essentially allowed to continue.  The environmental impacts are kept to a minimum – river habitats are essentially sustainable. Weaknesses:

 Potential production and income is not realised, due to the inability to further develop / irrigate areas that are already fully allocated in terms of their allowable water usage.  Times when the water is needed the most, ie during droughts, is when river and stream flows are at their lowest and there is little / no water available.  Debate exists as to what the minimum flows should be; the maximum rates of extraction that aquifers can cope with are still being established.

2. Develop strategies to better utilise the water currently available, eg store the excess water in times of plenty, using irrigation storage dams. Strengths:  Production and revenue are further increased by farmers’ being able to access water at times when the minimum flow restrictions previously prevented it.  Environmental impacts on river ecosystems and aquifer levels are kept at current levels. Weaknesses:  Storage dams have their own environmental impacts.  The cost of building these is high, often requiring local or central government assistance, and these structures have to comply with the Resource Management Act and other regulatory requirements. NCEA Level 3 Agricultural and Horticultural Science (90653) 2012 — page 5 of 5

3. Restrict the off-take of water for irrigation to a point where the impact on river and stream levels / ecosystems is negligible and water tables are unaffected. Strengths:  River ecosystems can be allowed to return to previous states.  Other social and recreational users (eg fishermen) can fully utilise the resource.  Our “clean, green” image with overseas markets and tourists is enhanced.  Water for stock, household, and other purposes remains available, and is of a higher, safer quality. Weaknesses:  Thousands of existing farmers who have installed irrigation systems, and who have collectively invested hundreds of millions of dollars to maintain economic viability, will be severely affected and in many cases rendered uneconomic.  The social impacts in many intensive farming regions, eg Canterbury, where irrigation has resulted in dairy cow numbers reaching 480 000 would be profound (eg drop in school rolls).  There would be substantial impacts on national production and export volumes for some products and in some industries. There would also be flow-on effects for producers in other, less intensively irrigated regions, due to reduced economies of scale and other factors, eg Fonterra shareholders.  Some dry regions would be at risk of reverting back to wind erosion-prone, weed infestation-prone landscapes and land uses.  Irrigation is a large contributor to the green appearance that New Zealand is famous for; less irrigation would mean more images of dry, arid land for both local and overseas observers.

Justification (example) The use of stored water is the best course of action. Water can be taken during times of high river flow, thereby avoiding the environmental issues associated with extraction during periods of low flow. The social impacts can be positive overall, with larger dams even having a recreational purpose (fishing, sailing, etc) and the economic benefits that result from irrigation of land can be significant – providing that the irrigation water is used for high- value crops and products. The capital cost of the schemes and instillation means it is not economically viable for sheep and beef farming, and even dairy conversion is marginal (Wairarapa irrigation scheme feasibility report 2009). Restricting water flows does provide some environmental safeguards, but damage is still sustained through both low water levels and reduced water quality. The likelihood that the permission to remove water would be stopped at times of low flow increases the economic risk of not having access to water when it is most needed. Socially, this is really a lose / lose situation for both the producer and the wider community.