Strategies to Increase Agricultural Sustainability

Issue: Decreasing nutrient supply

Current supplies of rock phosphates to produce phosphate fertilisers are non renewable.

What are the 2 ways to reduce the issue of decreasing nutrient supplies?

1. Use natural processes

2. Increase the natural nutrient supply

How to use natural processes to increase nutrient supply:

• Nitrogen-fixing bacteria. These bacteria naturally convert nitrogen from the air into a form plants can use.

• Decomposition. The breakdown of dead organic matter naturally releases nutrients back into the soil.

• Crop rotation. Planting different crops in a cycle helps maintain soil nutrients back into the soil.

How to increase natural nutrient supply:

• Recycling of organic matter - Using plant and animal waste to return nutrients to the soil

• Crop rotation

• Permaculture - A farming system that mimic natural ecosystem to maintain soil health and nutrient cycling

• Growth of legumes

• Conservation of soil biota

Issue: High amounts of Energy inputs

The manufacture of nitrate fertilisers requires large energy inputs from fossil fuels

What are the 2 sustainability strategies to minimise energy inputs?

• Using natural processes instead of artificial fertilisers

• Low tillage techniques

Issue: Decreasing Water Supplies

There is an overexploitation of rivers and groundwater reserves.

Soil salination is also caused by using saline irrigation water.

What are the sustainability strategies to conserve water supplies?

• Cultivating low water use crops
  

• Maintaining soil and soil organic matter
  

• Use of reservoirs and aquifer recharge
  

• Drip irrigation rather than overhead sprays

Issue: Atmospheric Pollution

• Atmospheric CO₂ levels increased
  

• Increased methane production in agriculture

How to reduce the atmospheric pollution from agriculture?

• Low tillage farming to reduce the decomposition of soil organic matter
  

• Reduced use of machinery
  

• Retain natural and semi natural ecosystems such as hedgerows, ditches, ponds, woodlands

How to make cattle produce less methane?

Feed them a high carb diet and grind their food first

Issue: Pesticide Usage

A reliance on chemical pesticides may be unsustainable.

The use of some pesticides has been banned or restricted due to their impacts on non-target species

Many pests have developed resistance to pesticides

What are 3 sustainable strategies to control pests?

1. Cultural pest control

2. Integrated control

3. Reduced use of antibiotics

Name the cultural pest control techniques

• Weeding

• Mulching

• Crop rotation

• Barrier crops

• Biological control

• Predator habitats

• Polyculture / companion crops.

What is integrated control?

An ecological approach to pest management, combining biological, cultural, and chemical control.

Name some integrated control techniques:

• Cultural pest control

• Growing pest resistant species

Why is the overuse of antibiotics bad?

Exposure to a high dose of an antibiotic may kill all of a pathogen population

 

• However, exposure to a lower dose of antibiotics may kill only the most sensitive individuals, so the surviving population will be less easily controlled by the antibiotic

• Also, increases in antibiotic resistant bacteria is an issue. Antibiotic resistant bacteria may be zoonoses, which cause disease if transferred to humans (E.coli)

Therefore, antibiotic use should be reduced.