Sustainability

Introduction

  • Sustainability: meets the needs of today without compromising future generations’ ability to meet their own
  • We must protect the environment.

What are the Issues?

  • Population growth is anticipated to reach 10 billion by 2050
  • 800 million people are undernourished, malnutrition, and hidden hunger (enough calories, missing minerals/vitamins)
  • with more money, people will want more meat and dairy

It’s not just a Science Issue

  • Plant scientists can’t fix all the issues.
  • The entire food system is determined by government regulation, social values, and ethical considerations

Agriculture

Intensive Ag

  • Intensive agriculture: gives a high yield but has negative effects on the environment
  • Lots of inputs, such as fertilizers and insecticides can run off into the water sources

Subsistence Ag

  • Subsistence agriculture: lower yields as people are too poor to purchase the inputs to improve yield.
  • Hurts the environment for different reasons (soil depletion)

All forms of agriculture hurt the environment

  • On-Farm: (Mostly in developing countries) soil nutrient depletion, over-grazing of cattle, deforestation to provide more land for crops, but soil quality is not sufficient for more than 1-2 years, and urban development.
  • Deforestation can cause erosion/loss of the topsoil; “slash and burn”
  • Off-Farm: high impact, intensive agriculture
    • Often in industrialized countries, the damage is off the farm “downstream” and the general public can suffer
    • The problem is too many inputs
    • overuse of water irrigation leads to decreased water availability
    • fertilizer and pesticide over-use leading to contamination
    • decreased genetic diversity in crops due to monocultures
  • In the developed countries major increases in yield have been recorded in the last half century without using more land - this is a result of agricultural intensification.

Yield Gap

  • Yield Gap: measures the difference between potential yield and actual yield
  • Potential yield increases with improved seeds and other inputs
    • Farm yield also increases with these inputs
  • There is still room for improvement
  • Over the last 80 years, the planting density of corn plants in the US has increased resulting in farm yield increases.
    • (Achieved through conventional breeding)
  • In developed countries, genetics and biotechnology have been responsible for most of the increased yields.
  • Most of the improvements through breeding and biotech have come with corn, and more recently rice.
    • Hybrid corn and rice have greatly improved yield
  • However, in developing countries, the yield gap is widening due to environmental deprivation and a lack of resources.
  • Reducing yield gap in developing countries
    • improved tools including farm machinery
    • New and improved varieties (GMO or non-GMO)
    • inorganic fertilizers
    • herbicides and pesticides
    • irrigation technology
    • information technology
    • but even low-tech improvements can help a lot

We have to be SMARTER

  • No-till Farming: (with or without herbicide) prevents soil erosion by allowing water to soak more gently into the ground, returns nutrients to the soil, builds up organic material in the soil
    • Only go through with tractors like 1 time
  • Precision farming: site-specific crop management; GPS can be used to monitor crop growth, color when fertilizer or water is needed, and how much.
  • Intercropping: rows of different things
  • relay cropping: growing one thing (like a cereal) and following it with another (like a legume)
    • Intercropping and relay cropping are done in small-hold farms where labor is plentiful but research has shown it can be done in large farms with technology.
  • Soil microbiology: identifying beneficial microbes
  • Water management: (Pros and cons of irrigation) and management to reduce water loss
    • Water Management Ss
    • Stop your water by making channels, swales, bunds, or check dams
    • Spread your water along the contour of your land
    • Sink your water into the soil, the healthier your soil becomes the more water it can absorb
    • Shade your water using trees as groundcover and mulch to ensure it stays in the soil for as long as possible
  • More efficient nutrient use to prevent overuse
  • Wider acceptance of GMO crops is needed to allow for all technological options to use.
  • Research must continue not just on staple crops but also on minor ones
    • CGIAR institutes for conducting research on minor crops, especially ones that nutritionally important in underdeveloped countries
  • However, in addition to basic research at experiment stations, applied research that is farm-based is necessary to get “buy-in” from local farmers to sow new seed varieties, purchase or borrow new machinery, and use the best agronomic practices

Environmental Services

  • Maintaining a resource base is essential for food production.
  • That means maintaining soil quality, water availability, genetic resources, and the natural environment
    • Soil Quality: need to maintain nutrients (replenish them with fertilizer and organic material).
    • Irrigation can reduce soil quality by leading to a build-up of unwanted salts
    • New irrigation schemes should be located where there is nearly sufficient water, rather than in dry areas
    • However, it is VERY important that aquifer levels are not depleted too much by irrigation schemes

Ecosystem services

  • Carbon fixation
  • Nitrogen fixation
  • Water Cycling
  • nutrient cycling
  • preservation of pollinators and symbiotic organisms

Climate change

  • Climate change affects both high-impact, high-intensity farming, and subsistence farming as well as everything in between.
  • There is no escape.
  • Agriculture contributes to climate change and climate change can affect agriculture.
  • In some places, climate change may increase yield but in most places, it will be damaging
  • Too hot, too dry, natural disasters may become more intense (hurricanes, typhoons)

Public Policy

  • government subsidies are determined by the area planted, yield, and target price
  • Subsidies are used to encourage farmers to use non-sustainable practices

Recommendations

  • Develop crops that have low water use, better nutrients uptake, temperature tolerance, etc
  • Have crop rotation and intercropping instead of monoculture to maintain biodiversity
  • Use “integrated pest management” instead of pesticides as the first line of defense
    • biological control
    • cultural control
    • mechanical/physical control
    • reproductive/genetic control
    • chemical control (last resort)
  • Try to implement strategies to slow the development of resistant pests.
    • Use rotation, mosaics, refuges
  • We must adopt the best technology available, but also consider the human aspects
    • conflict resolution
    • make globalization work for poor people
    • debt reduction, etc.
    • microfinancing
  • One thing is sure, we can’t go back to farming the pre-Green Revolution way