Ch 5.5 Can modern agricultural technologies increase farm production sustainably? Flashcards
What are the limitations of farming technologies?
- Misuse and overuse of pesticides and herbicides.
- Excess use of nitrate fertilizers (Eutrophication).
- Overdrawing groundwater for irrigation.
- Use of farming machines.
- Global warming.
- Safety of GM foods.
Elaborate on misuse and overuse of pesticides and herbicides as one of the limitations of farming technologies.
- Kill target pests and other insects but some pest species may become resistant to pesticides -> become super pest
- Certain insects and plants are killed completely.
- Kill the bacteria and fungi in the soil.
- Being washed into the rivers or lakes.
- Pollute the groundwater.
- Residual traces of pesticides on crops.
Elaborate on certain insects and plants are killed completely as one of the points of misuse and overuse of pesticides and herbicides as one of the limitations of farming technologies
- Other insect and plant species may suddenly rise in number.
- Loss of diversity and breakdown of food chain.
- Destroy the balance of the ecological system.
Elaborate on kill the bacteria and fungi in the soil as one of the points of misuse and overuse of pesticides and herbicides as one of the limitations of farming technologies.
- Slow down the rate of decomposition, resulting in fewer organic matters in the soil.
- Soil degradation.
- Destroy the balance of the ecological system.
Elaborate on being washed into the rivers or lakes as one of the points of misuse and overuse of pesticides and herbicides as one of the limitations of farming technologies.
- Water pollution
- Wildlife may be killed.
- Destroy the balance of the ecological system.
Elaborate on pollute the groundwater as one of the points of misuse and overuse of pesticides and herbicides as one of the limitations of farming technologies.
- Pesticides and herbicides are washed into the rivers and lakes or percolate into the groundwater.
- Pollution of drinking water.
- Harm people’s health.
Elaborate on residual traces of pesticides on crops. as one of the points of residual traces of pesticides on crops as one of the limitations of farming technologies.
- Contaminate food products.
- Harm people’s health.
Elaborate on excess use of nitrate fertilizers as one of the limitations of farming technologies.
-> More nutrients for water plants and algae.
-> Algae blooms.
-> Toxins from algae can kill fish and other aquatic organisms.
-> Water plants die.
-> When dead plants and algae are decomposed -> oxygen is used up.
-> Fish and other organisms suffocate.
-> Destroy the aquatic ecosystem
Elaborate on overdrawing groundwater for irrigation as one of the limitations of farming technologies.
- Land subsidence.
- Contaminate freshwater supply.
- Salinization of soil.
Elaborate on land subsidence as one of the points of overdrawing groundwater for irrigation as one of the limitations of farming technologies.
-> Rate of groundwater withdrawal is faster than the rate of replacement.
-> Water table drops.
-> Groundwater is depleted.
-> Land collapses.
Elaborate on contaminate freshwater supply as one of the points of overdrawing groundwater for irrigation as one of the limitations of farming technologies.
Salt water intrude into the groundwater.
Elaborate on salinization of soil as one of the points of overdrawing groundwater for irrigation as one of the limitations of farming technologies.
-> Irrigation water can dissolve salts in the soil and leach them to the subsoil.
-> Under dry climate, evaporation rate is high.
-> Evaporation draws up the dissolved salts to the topsoil.
-> When the water evaporates, the salts are left to the top soil. -> form a salty crust
-> High concentration of salts limits the water absorption of crops.
-> The land becomes unproductive -> land degradation.
Elaborate on use of farming machines as one of the limitations of farming technologies.
- Powerful ploughing machines.
- Heavy farm machines.
Explain on powerful ploughing machines as one of the points of use of farming machines as one of the limitations of farming technologies.
-> Loosens the soil through deep ploughing
-> Accelerates wind and water erosion.
->Soil erosion speeds up.
-> Top soil is lost.
-> Soil fertility and land productivity drop.
Explain on heavy farm machines as one of the points of use of farming machines as one of the limitations of farming technologies.
-> Compacts the soil.
-> Infiltration drops.
-> Surface run off rise.
-> Accelerates water erosion.
-> Soil erosion speeds up.
-> Top soil is lost.
-> Soil fertility and land productivity drop.
Explain on global warming as one of the limitations of farming technologies.
- Overusing nitrate fertilizers release large amounts of nitrous oxide.
- Running farm machines increases the consumption of fossil fuels, and leads to more greenhouse gases emission especially carbon dioxide.
Explain on safety of GM foods as one of the limitations of farming technologies.
- Increase resistance of weeds and pests to chemicals.
- Undesired gene movement.
- Transfer of allergies.
- Viruses spread across species.
- Inadequate control on the application of GM crops.
What is sustainable farming?
Sustainable farming encourages the use of eco-friendly farming methods. It causes fewer disturbances to the fragile environment and maintains a balance between three aspects.
What are the five ways to achieve sustainable farming?
- Water conservation.
- Soil conservation.
- Precision farming.
- Integrated pest management.
- Organic farming.
Elaborate on water conservation as one of the five ways of sustainable farming.
- Irrigate at night.
- Use treated urban waste as irrigation.
- Grow water-efficient crops e.g. drought-resistant crops.
- Practise dry farming.
- Use high-tech sensors that calculate the water needs of crops.
- Using the technique of water harvesting to catch rainwater from slopping lands by digging microbasins/ semi-circular band/ half moons/ demi-lune. -> allow water to seep into the soil -> retain soil moisture and prevent loss of fertile soil
What is dry farming?
It is often described as crop production without irrigation during a dry season. (a dry-farmed crop is irrigated once or not at all)
What is half moon?
Semi-circular hide open basins used to collect run off water. Most of the half moons must face a slope where rainfall will flow during precipitation.
What is the ways of soil conservation?
- Multiple cropping.
- Cover cropping.
- Mulching.
- Planting windbreaks.
- Agroforestry.
- Contour-ploughing.
- Terracing (built on slopes)
- Conservation tilage.
- Crop rotation.
- Fallowing.
- Mixed farming.
- Building dignettes/ mini-dam.
- Using eco-friendly rock phosphates, lime, caffle manure and mineral fertilizers.