Impacts of Climate Change
2. Biological: Sunburn on the fruit skin and increased transpiration leading to water stress.
3. Economic: Fruit is downgraded to juice quality, which means a lower price, and irrigation costs increase significantly.
Question 1
1 Mark: Identifying a principle. e.g., maintaining ground cover/stubble.
1 Mark: Linking it to drought. e.g., this keeps the soil temperature cooler and prevents the little moisture available from evaporating.
Question 2
1 Mark: Identifying the timing issue. e.g., grains need early rain for germination.
1 Mark: Biological impact. e.g., later rain means a shorter growing season, leading to smaller plants.
1 Mark: Quality impact. e.g., shrivelled grain kernels or lower starch content.
1 Mark: Economic impact. e.g., lower yield per hectare (t/ha) leads to reduced farm income.
Sustainable Strategies - Climate Change
Which impact does it address? Heat stress and frost damage.
How is it sustainable? The mulch improves soil health by retaining moisture, while the misting protects the economic viability of the crop without requiring permanent land clearing.
Question 1
Adaptation (1.5 marks): Stubble acts as a blanket, keeping soil cool and retaining moisture during drought.
Mitigation (1.5 marks): By not ploughing the soil, carbon is kept underground rather than being released into the atmosphere as CO2.
Question 2
Animal Welfare (2 marks): Provides shade and wind protection, reducing metabolic stress and improving milk production/weight gain.
Carbon Sequestration (2 marks): The trees physically capture CO2 from the air and store it in their biomass (trunks and roots), offsetting the farm's emissions.
Sustainable Strategies - Climate Change
Dairy: Place on the Class 1 flat land. Cows are heavy and walk around as they graze; putting them on steep land would cause soil compaction and erosion. The rich soil can also support the high-nutrient grass they need.
Timber: Place on the Class 4 steep land. Trees stabilise the soil on slopes with their roots, preventing landslides, and can grow in rocky soil where pasture would fail.
Question 1
1 Mark: Land capability is the inherent ability of a parcel of land to support a specific use without suffering permanent damage or degradation.
1 Mark: It is the "foundation" because if you exceed capability, you cause environmental degradation (like erosion), which makes the farm unprofitable and unsustainable in the long term.
Question 2
1 Mark: Environmental—Potatoes require constant tilling; on a steep slope, this will lead to massive topsoil erosion during rain.
1 Mark: Economic—Loss of topsoil means the farmer will have to spend more on fertilisers to replace lost nutrients.
1 Mark: Long-term—Eventually, the soil will be too poor to grow anything, destroying the "capital value" of the land.
Types of Environmental Degradation
Question 1
1 Mark: Native trees are deep-rooted and keep the water table low. Clearing them replaces them with shallow-rooted plants that use less water.
1 Mark: The excess water enters the groundwater, causing the water table to rise and bring dissolved salts into the root zone of the crops.
Question 2
1 Mark: Low pH (acidity) makes essential nutrients like phosphorus less available to the plant.
1 Mark: It can lead to aluminum toxicity, which stunts root growth.
1 Mark: The economic impact is lower yields and poor crop quality.
1 Mark: Management strategy—Applying lime (calcium carbonate) to the soil to raise the pH level.
Techniques for Prevention
Example Answer: A beef producer in Gippsland constantly grazed heavy cattle on wet pastures during winter. This caused severe soil compaction and blocked water drainage. To rehabilitate the land, the producer had to buy a deep-ripper attachment to break up the hardpan soil and a laser-guided raised bed former to lift the next crop's roots out of the stagnant water.
Question 1
1 Mark: It confines all heavy machinery tyres to the exact same tracks every season.
1 Mark: This ensures that the majority of the paddock area never experiences the heavy wheel loads that squeeze out soil air spaces.
Question 2
1 Mark: Native trees on hillsides transpire large volumes of water throughout the year.
1 Mark: This biological water use lowers the underground water table across the catchment landscape.
1 Mark: A lower water table stops dissolved underground salts from being pushed up into the root zone in the valley.
1 Mark: This allows vegetation to regrow in the valley, improving soil structure and preventing salty surface runoff from entering local waterways.
Water Quality
Lack of Riparian Fencing: Cattle are likely entering the creek, trampling the banks and causing soil to collapse into the water, which explains the high turbidity.
Effluent Runoff: Animal waste or fertiliser is entering the stream, introducing organic matter that consumes oxygen as it breaks down, explaining the low dissolved oxygen levels.
Question 1
1 Mark: The phosphorus washes into the creek during rain, acting as a nutrient source that triggers an algal bloom.
1 Mark: When the algae dies, bacteria decompose the organic matter, consuming the dissolved oxygen in the water during the process.
Question 2
1 Mark: High EC indicates a high concentration of dissolved salts in the water.
1 Mark: This increases the osmotic pressure around the roots, making it harder for the fruit trees to draw water from the soil.
1 Mark: Over time, salt accumulates in the root zone, causing leaf burn, reduced fruit yield, and potential toxicities.
Sustainable Strateies
Upgrade A (Environmental): Reduces water loss to evaporation and stops weed seeds from germinating between rows due to dry surface soil. (Economic): Lowers pumping costs because less water volume is moved, saving money on electricity.
Upgrade B (Environmental): Lowers the carbon footprint of the dairy by displacing fossil-fuel grid power with renewable energy. (Economic): Reduces the quarterly power bill for milk cooling and harvesting, boosting the cash flow of the business.
Question 1
1 Mark: Probes provide real-time data showing exactly how much water is available in the root zone.
1 Mark: This allows the grower to schedule irrigation only when necessary, preventing water waste from over-watering or leaching past the roots.
Question 2
1 Mark: Short-term environmental - The use of solar power directly reduces the volume of diesel burned, lowering immediate greenhouse gas emissions.
1 Mark: Short-term economic - The farm experiences an immediate reduction in running costs due to lower diesel fuel purchases.
1 Mark: Long-term economic - While the initial capital cost of the solar infrastructure is high, it protects the farm business against future fossil fuel price spikes.
1 Mark: Long-term environmental - The reduction in local fuel transport and storage minimises the risk of diesel spills near the river ecosystem and/or prevents pollution from fumes.
Natural and Managed Ecosystems
Soil Health: The clover fixes atmospheric nitrogen into the soil, reducing the need for synthetic fertilizers, while the deep radish roots break up compacted layers.
Pest Management: The flowering plants attract beneficial predatory insects that prey on light brown apple moth larvae, protecting the grape harvest without chemicals.
Question
1 Mark: Clearing native vegetation destroys the permanent habitat and food source for native, wild pollinators.
1 Mark: This makes the grower entirely dependent on rented beehives, increasing financial costs and vulnerability if bee diseases emerge.
1 Mark: Removing native vegetation also eliminates the habitat for predatory insects and birds that naturally keep pest populations in check.
1 Mark: As a result, pest pressure will likely increase, forcing the grower to rely on expensive chemical pesticides, which further reduces biodiversity.
Modifying the Environment
Question 1
1 Mark: Frost fans pull down warmer air from the inversion layer to raise the temperature above freezing at the vine canopy level.
1 Mark: This prevents ice crystals from forming inside the plant tissue, protecting the delicate green shoots and flowers from cell wall rupture and death.
Question 2
1 Mark: Unmodified slopes cause water to run off rapidly due to gravity, picking up speed and washing away fertile topsoil.
1 Mark: Rapid runoff also means less water infiltrates the soil profile, leaving the crop vulnerable to water stress.
1 Mark: Modification solution - The grower can implement terracing or construct contour banks across the slope.
1 Mark: How it helps - This physical barrier intercepts the downward flow of water, slowing its velocity and allowing it to safely soak into the ground or drain away without stripping the soil.
Symptom 1: Use a turbidity tube to test the creek water. You are monitoring suspended sediment to check for bank erosion caused by stock.
Symptom 2: Take a soil core sample to test the soil pH. Yellowing leaves often indicate an acidity issue locking up essential crop nutrients.
Symptom 3: Mix a soil sample with distilled water and test it with an EC meter. You are tracking the electrical conductivity to diagnose potential dryland salinity.
Question 1
1 Mark: Different macroinvertebrate species have known, specific tolerance levels to pollution and low oxygen.
1 Mark: By identifying the diversity of species present, a manager can evaluate the long-term water quality because the bugs live in the system constantly, unlike a single water test which only captures a snapshot in time.
Question 2
1 Mark: NDVI drone mapping provides a spatial visual of the paddock, allowing the grower to isolate exactly where the crop is underperforming or showing low chlorophyll activity.
1 Mark: Once the poor zones are identified, targeted bulk density core sampling can be conducted in those exact areas to measure the physical compaction of the soil profile.
1 Mark: If the bulk density is high, it reveals that the roots are physically restricted from growing deep enough to access moisture and nutrients, rendering the fertilizer ineffective.
1 Mark: The combination allows the grower to move from guessing to applying a precise physical solution (like deep-ripping) to rehabilitate the specific zones of degradation.