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QUESTION 15 The table shows livestock’s approximate tolerances to dissolved salts in drinking water. Livestock No adverse Reluctance Decline in condition effects (g/L) to drink (g/L) and health (g/L) piss POO | p 10-50 5.0 p 50-70 7.0 Identify the livestock that would suffer a loss in production with a total dissolved salt measurement of 4820 mg/L. (A) pigs (B) horses (C) beef cattle (D) dairy cattle
QUESTION 24 (4 marks) A cattle producer has a creek running through their property. The creek provides water for cattle and the irrigation of fodder crops and improved pastures to boost animal production. After experiencing a year with significantly less than average rainfall the producer notices that native vegetation along the creek bank is dying off the creek water is more discoloured than usual and the leaves in the fodder crops and improved pastures are yellowing. Explain two strategies the producer could implement to reverse the processes that are occurring on the property.
QUESTION 6 (3 marks) a) Explain one reason for a producer to clear land on their property. [1 mark] b) Describe one short-term effect and one long-term effect land clearing may have on the soil. [2 marks]
QUESTION 4 The table shows grain yield from a field trial for two varieties of oats at different rates of nitrogen application. Rate of nitrogen | Variety 1 | Variety 2 applied (kg/ha) (kg/ha) (kg/ha) 2.4 2.4 3.4 3.4 5.1 4.6 ws Which conclusion can be supported by the data? (A) Variety 2 demonstrates the largest positive response to nitrogen application. (B) Both varieties show a decline in yield at the same rate of nitrogen application. (C) Variety | requires less nitrogen fertiliser than Variety 2 to achieve optimal production. (D) Other major nutrients are limiting grain yield for Variety 2 at an application rate of 80 kg/ha.
QUESTION 27 (7 marks) A trial was conducted on a double-crop rotation system using nitrogen supplied in different forms to evaluate the effects of different fertilisers on crop yield. The different kinds of common organic fertilisers used and compared to the control treatment (C) were: ¢ general organic fertiliser (GOF) ¢ biogas residue (BR) ¢ refined organic fertiliser (ROF). Both crops of tomato used the same variety. The graph shows the mean yield for each crop and fertiliser treatment. Error bars represent 95% confidence intervals. 120 100 i t = 80 : = rz a = 60 Ye Y Uj 3 Y Y - 40 ] ] ] C GOF BR ROF Treatment Key || Tomato 1 Celery p Tomato 2 a) Explain why nitrogen is important for plant growth in agricultural crops. [2 marks] b) Analyse the data to identify the relationship between the type of fertiliser applied and celery yield. [1 mark] c) Decide which fertiliser tomato farmers should use to optimise production in this cropping system. Justify your decision with two pieces of evidence and give a reason this type of fertiliser would be expected to improve the yield of a tomato crop. [4 marks]
QUESTION 9 (5 marks) Several key management issues can affect sustainable agricultural production. a) Identify a management issue shown in the image. Explain two processes that may have contributed to the issue identified in Question 9a). /2 marks] Propose two solutions for the issue identified in Question 9a). [2 marks]
QUESTION 10 (15 marks) Case study A pastoral company is a 9000-ha sheep and cattle production system situated in southern Queensland in the wheat-—sheep belt. It runs 26 000 merino sheep and 800 breeding cows. The land is predominantly native pastures and shrubs on sandy to loamy topsoils with low fertility and poor water holding capacity. The annual average rainfall is 600 mm. A creek runs through the property and there are several permanent waterholes. There are some patches of soil erosion along the creek where livestock access the creek for drinking water. The company is working to become carbon-neutral in support of the red meat industry goal of carbon neutrality by 2030. Carbon emission reduction strategies being used on the property include: * genetics — using composite sires and breeding for early finishing in lambs ¢ lot feeding — reaching market compliance faster by moving to a feedlot situation for finishing ¢ productivity — using a combination of genetics and livestock management to increase wool production from 440 tonnes in 2018 to 800 tonnes in 2024 vegetation and land management — using 20% of the land area for conservation and biodiversity. Most of this vegetation is contained to wildlife corridors 30 to 50 m wide. Larger paddocks have been cut up into smaller paddocks surrounded by shelterbelts. Creeks have all been fenced off and all paddocks now have permanent water sources supplied by a combination of bore and dam water. The company has an issue with flystrike in its sheep. Approximately 3% of the flock is affected annually which is higher than the industry average of 1.5 to 2%. Stock is only purchased from known producers and health declarations are essential for any incoming stock. The company keeps new animals in its quarantine paddock for a minimum of 10 days before they are introduced to new pastures flocks and herds. Currently there is little control of run-off from the feedlot. Although the feedlot is scraped and the top layer of waste is removed this does not often happen within the industry standard of every 13 weeks. Run-off is stockpiled on the farm and sometimes becomes odorous. The manager has reported that manure waste often ends up in the creek after storms. Refer to the case study. Use three environmental management criteria to assess sustainable practices in the production system. For each criterion analyse and justify three strengths and/or weaknesses. Draw a justified conclusion about the sustainability of the production system.
QUESTION 19 What most effectively reduces turbidity levels in creeks located in extensive cattle operations? (A) building weirs or dams (B) erecting stock fences around the creek (C) reducing fertiliser run-off from paddocks (D) implementing a rotational grazing strategy
QUESTION 3 (4 marks) The graph shows the yield of five wheat varieties grown under differing levels of salinity. Bars represent 3-year mean grain yield values along with standard error. a) b) Yield (kg/ha) Key |_] slightly saline Wheat variety moderately saline WH strongly saline Contrast the levels of uncertainty in the data collected from moderately and strongly saline soils. Show your reasoning using evidence from the graph. Infer whether variety | is the best option to plant in strongly saline soils. Justify your answer using evidence from the graph. [2 marks] [2 marks]
QUESTION 6 (4 marks) Explain two ways a natural resource is influenced by land clearing.
QUESTION 4 The graph shows the population data for edible marine species found in a native fishery. 50 40 = Species P Dm — v Danieteneieltineielieeciadiimanedeieaiadaaaiinieaimmneamanta ai ait “nada” aa 5 30 —_ ° _-’ Species Q ‘S -Species R < 20 a a 10 LL a a Species S TS PAPE SS SSE SKELASSS BD? OD? DE QD QW” WW” 7 WN SS SS SHPO HH a HW’ Which species would be most suitable for establishing a sustainable agricultural enterprise? (A) Species P (B) Species Q (C) Species R (D) Species S
QUESTION 12 The graph shows the soil erosion potential for different agricultural land uses. 100 90 80 | Key [_] Bare soil Continuous grazing and tree clearing WH Continuous grazing and regrowth control Pasture spelling and continuous tree clearing Pasture spelling and regrowth control Soil erosion potential (%) Land use What would be the reduction in the percentage of soil erosion if pastures were spelled with control of regrowth compared to continuous grazing and tree clearing? (A) 18% (B) 28% (C) 68% (D) 83%
QUESTION 11 (18 marks) An 8000-hectare cropping/grazing property in Central Queensland runs 400 breeding cows on improved pastures (mostly buffel grass) and includes a feedlot to finish the steer offspring. It also grows irrigated crops including cotton in summer and wheat barley and chickpeas as crop rotations in winter. The cotton used is a variety genetically modified to make it resistant to a common herbicide and contains a gene that codes for the production of Bt toxin. The toxin causes the caterpillar pest Helicoverpa sp to die when it consumes the cotton leaves. Water for irrigation comes from the Nogoa River which runs through the property. Water is supplied to the Nogoa River from the Fairbairn Dam as per the irrigation licence for the enterprise. Water is then recycled through a catchment system and reused on property using water storage. Irrigation timing 1s based on visual appraisal of the crop. The cattle are Santa Gertrudis made up of 5/8 Bos Taurus and 3/8 Bos Indicus. The steers produced are finished on the property with the feedlot located uphill from the river. Waste is removed from the feedlot and stockpiled nearby and this sometimes flows into the river during heavy storms. The cattle are grazed using a rotational grazing system with smaller paddocks. Half of the paddocks have a permanent water supply through troughs linked to a pump in the river. The paddocks that are located near the river use it as a water source for the cattle. Irrigation Water Irrigation channel catchment channel Cropping area Cropping area Manure Feedlot Cattle Permanent waste paddocks water source River Not to scale Use three environmental management criteria to assess sustainable practices in the production system. For each criterion identify three strengths or weaknesses. Draw a justified conclusion about the environmental sustainability of the production system. Explain two management practices that would improve aspects of this enterprise’s environmental sustainability.
QUESTION 19 The figure below shows crop tolerance to soil salinity. 100 CI | 4 80 TT NIT r SS z | | | 2 60 aa - —_. Yields unacceptable-— = | for most crops S | Poo ) | |_| 2 40 | FE Ai | | | | QT NEE ARKH FH HH] eB) 6 Foo | 20 Ss ee Se A Oe ee so ee | im Moderately \ Moderately ~ bp NG Sensitive sensitive tolerant Tolerant 0 | | 0 5 10 15 20 25 30 35 Electrical conductivity (dS/m) For which of the following ranges of soil salinity would an agricultural crop classified as tolerant record a relative crop yield of 80%? (A) 24.0-32.0 dS/m (B) 2.5-14.5 dS/m (C) 9.5-14.5 dS/m (D) 5.5-9.5 dS/m
QUESTION 23 (4 marks) Explain two strategies that a producer could implement to increase the level of agricultural production on soil with an elevated level of salinity.
QUESTION 3 (4 marks) Explain two effects that land clearing has on natural resources.
QUESTION 12 Refer to Stimulus | in the stimulus book. Question 12 has four parts: a) b) c) and d). You must respond to all four parts. Assess the opportunity that the family has for sustainable practices in their operation. a) Explain three positive practices in their current management. b) Identify two management actions that the manager could take that would improve sustainability. Address water/soil management and weed management. Give reasons to support each action. c) Identify three future risks that the family should manage for their operation to remain sustainable. d) For one of the identified risks explain why it would be considered a risk to the future sustainability of the family’s operation. [9 marks] [6 marks] [3 marks] [2 marks]
QUESTION 7 Which strategy would most effectively reduce turbidity in a creek running through an extensive cattle operation? (A) erect stock fences along the creek (B) remove aquatic vegetation from the creek (C) limit the stocking rate of cattle over the operation (D) increase the level of chemical control of weeds along the creek bank
QUESTION 27 (6 marks) The graphs show the erosion rate of soil on two blocks of land of varying slopes one covered in grass and one covered in trees and shrubs. Grass Measured erosion rate (t/ha/yr) 0 5 10 15 20 25 30 35 Slope degree Measured erosion rate (t/ha/yr) Trees and shrubs 0 5 10 15 20 25 30 3 Slope degree a) Identify differences in the erosion rate of soil on the two blocks of land. The graph shows a cross-section of land for an animal production area. b) Slope > 40° G a oe oO an A Using the data from Question 27a) decide whether grass or trees and shrubs would be more suitable for sustainable animal production on sections A and B. Justify your conclusions. 5 [2 marks] [4 marks]
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