Activity 3.1 – Agriculture 101

• History of Agriculture

• Pre-Modern Agriculture

• Animals require nutrients to survive

• Most populations originally nomadic hunters and gatherers

• Change from hunting and gathering to more complex systems happened 10,000 yrs ago

• Southwest Asia 

• Early holocene (9,500 B.C.)

• First instance of planted crops

• Grains, lentils, peas, lentils, vetch, flax

• Persian Gulf (Fertile Crescent) and China

• 7,000 B.C.

• Domesticated animals: Sheep and goats plus oxen for labor

• Americas

• 3,000-2,700 B.C. 

• Plants such as maize, potato, tomato, pepper, squash, and beans 

• Development of agriculture led to

• Settlements 

• Greater population density

• Armies to protect croplands

• More advanced agricultural techniques

• Crop rotation 

• Manure fertilization

• Terraced rice fields

• Cattle plowing

• Irrigation systems

• Agricultural exchange led to

• Globalization 

• Atlantic slave trade 

• From the 1800’s on

• Advanced breeding techniques

• Nitrogen and phosphorous crop fertilizers

• Vitamins for livestock

• Tractors

• Doubled crop production

• Utilized fossil fuel

• Dangers of monoculture discovered

• Moving Towards Modern Agriculture: The Green Revolution

• Green revolution

• Cereal grain production boom after WWII

• Crop production increases dramatically

• Chemical warfare led to agrochemicals 

• Agroscience leads to 

• Chemicals

• Industrial containment 

• Vitamins 

• Antibiotics

• Genetic engineering

• Limitations of industrial agriculture

• Productivity must continually increase to match growing populations

• Production has not increases due to 

• Social and political conflicts 

• Land degradation

• Economic market volatility

• Push for lower cost and more production leads to 

• Pollution

• Pesticide resistance

• Changing conditions for crops

• Issues of Modern Agriculture

• Water Pollution from Fertilizers

• Nutrients can benefit crops but run-off into waterways can cause a range of problems

• Nitrates (NO3)

• Occurs naturally and synthetically

• Common compound needed for plant growth

• Very water soluble 

• Easily disintegrated and washed away with water

• Causes blue baby syndrome

• Phosphorus 

• Essential for plant growth 

• Occurs naturally and synthetically 

• Less water soluble 

• Moves soil particles with it

• Accumulates in larger bodies of water

• Causes algae blooms 

• Makes the water unfit for 

• Habitation

• Drinking 

• Recreation 

• Pesticides and Pesticide Resistance

• Weeds compete with crops for resources

• Pests feed on the leaves, stems, and fruit of crops

• Chemical sprays aka pesticides are used reduce damage caused by pests

• Herbicides

• Control weeds

• Can also harm crops

• Led to genetically modified crops that can withstand herbicides

• Glyphosate the most common broad spectrum herbicide

• Can produce herbicide resistant weeds

• Insecticides

• Control insects

• Applied to seeds or directly to crops 

• Neonicotinoids

• Major class of insecticides

• Does not break down easily

• Can pollute waterways, killing beneficial insects such as bees

• Climate Change

• Agriculture and forestry make up 24% of global greenhouse gas emissions

• Agricultural activities contribute to climate change such as

• Cultivation of soil releases carbon dioxide CO2

• Nitrous fertilizers release nitrous oxide N2O

• Livestock belching and decomposing manure releases methane CH4

• Sustainable agriculture can also act as a “sink” or storage for greenhouse gasses 

• Presents opportunities and challenges for agriculture 

• Opportunities 

• Longer growing seasons in the north 

• More options for crops grown there 

• Flexibility when planning

• More favorable growing conditions for some crops 

• More productivity

• Challenges

• Better conditions for pests and diseases leads to increased number and intensity 

• More severe weather events 

• loss of crops 

• Droughts and higher temperatures 

• Loss of crops 

• Land has less agricultural potential

• Cons of climate change for agriculture outweigh the pros 

• Soil Loss

• Soil is important in agriculture because it 

• Holds nutrients and water

• Helps anchor plants through their roots

• Protects from flooding 

• Helps get water from the surface to the subsurface 

• Agricultural practices can contribute to soil loss 

• Tillage 

• Breaks up top soil to encourage plant growth

• Can dry out soil causing it to blow or wash away

• Destroys beneficial fungi in the soil

• Leaving a field fallow

• Used to reduce

• Weeds

• Potential for disease

• Build up nutrients in soil

• Can also allow soil to move over time 

• Removing stubble from fields in the fall/removing or not planting trees

• Stubble and trees capture soil in wind and prevent it from blowing away

• Stubble can also capture snow in the winter, improving soil moisture

• What is Sustainable Agriculture?

• Defining Sustainable Agriculture

• Sustainable Agriculture considers natural ecological functions such as

• Nutrient cycling 

• Biodiversity 

• Evolution 

• Focuses on reducing fossil fuels like pesticides and fertilizers 

• Benefits include

• Improved soil health 

• Reducing pests and weeds 

• Promotes biodiversity 

• Biodiversity plays important role in pest and weed control

• Mainly used as subsistence farming 

• Supports a small community with little no no leftover produce

• Typical in developing countries

• Example: slash and burn agriculture 

• Methods include 

• Integrated pest management

• Organic farming through intercropping

• Maintenance of biodiversity

• Food Security and Food Safety

• Food security

• When everyone has reliable access to safe and nutritious foods at all times 

• Achieved through sustainable food and agriculture practices

• Food sovereignty 

• People’s right to sustainably produced, healthy food and 

• People’s right to define their own food and agriculture systems 

• Food insecurity 

• Inadequate food based on 

• Quality 

• Quantity 

• Nutritional value

• Food safety

• Desire to maximize profits leads corporations to use GMOs, pesticides and preservatives 

• Consumers grow more suspicious of food

• Complexity of the Agricultural and Food Production System

• Agriculture and food production today is extremely diverse and complex

• Can range from one small family business to multi-glomerates 

• Multi-glomerates are massive corporations that control a large portion of world 

  food production

• Global markets and farmers markets 

• Large, multi-national companies 

• Do not sell directly to consumers 

• Control a significant amount of the world’s food production

• According to greenpeace

• Six corporations control 75% of the world’s pesticide market

• Worldwide, factory farms account for 

• 75% of poultry production

• 43% of egg production 

• 55% of pork production

• Four corporations control more than 75% of global grain trade

• Most of the world’s food is controlled by 10 major corporations that make $1.1 billion in 

  profits daily

• Many consumers support farmer’s markets, food co-ops and CSA programs to 

• Know who produces their food

• Know the level of freshness

• Support local economies

• Number of farms is decreasing while size of farms increases

• It is becoming less economically sustainable to maintain small local farms

• While total farmland is staying consistent, the number of farms is steadily decreasing

• Women on family farms also play a key role in the productivity of the farm on top of maintaining 

  a functioning household

• this could present solutions when exploring sustainability and agricultural security

• Practices in Sustainable Agriculture

• Integrated Pest Management

• An environmentally friendly way of managing and controlling pests

• Goal is to prevent pest arrival based on information from

• Inspection

• Monitoring 

• Reporting

• Strategies implemented to combat pests include

• Removing factors that attract pests

• Clutter

• Standing water

• Food

• Pest trapping 

• Heat and cold treatment

• Physical removal 

• Pesticides as a last resort

• Thailand and Vietnam combat pests by 

• Encouraging natural predators to feed on pests

• Using clean pest resistant seeds

• Using minimal fertilizer

• Improve human health and saves money, but more labor intensive

• Organic Farming through Intercropping

• Intercropping is used in subsistence farming

• Based on management of plant interactions to maximize yield 

• Involves cultivating polyculture (two or more) crops 

• Benefits

• More efficient use of land

• Sustainable yield

• Reduced crop loss

• Erosion control

• Reduced loss of nutrients 

• Soil fertility maintenance 

• Balanced distribution of labor

• Higher profit than monocultures 

• Two main methods:

• Temporal intercropping 

• Crops are grown simultaneously for the most part, but do not have to be sown 

  or harvested at the same time 

• Most successful when asynchronous 

• Spatial intercropping 

• Arrangement of crops on a field 

• Enhancing Biodiversity in Agroecosystems

• Biodiversity plays key role in improving and maintaining ecosystems in the face of environmental pressures

• Diverse communities are more resistant to external stresses

• Diversification can help improve crop systems through resource partitioning 

• Biodiversity can be enhanced by 

• Utilizing cover crops to 

• Attract pollinators

• Reduce water loss

• Supply useful nutrients

• Using more than one cultivar of a crop to increase genetic diversity

• Goal is to sustain ecosystem functions and improve system resilience

• Linked to ecosystem services

• Provisioning 

• supporting/regulating 

• Cultural 

• New Trends: Diversified Agroecological Farming

• Agriculture poses prevalent threat to biodiversity

• 75% of plant and animal species which have gone extinct in the past 500 years were 

  impacted by agriculture and over-exploitation

• Agricultural land use and intensification endanger over 60% of threatened species 

• Tweaking agricultural practices can help but a fundamentally different model is required to solve 

  long-term problems

• Diversification techniques are based on agroecology

• A science which uses ecology to promote sustainable food production, the key characteristics being:

• Temporal diversification

• Wide range of species

• Natural synergies emphasized and production types integrated

• Labour-intensive systems

• Maximization of multiple outputs

• Low external inputs

• Production of a wide range of less homogeneous products

• Reduction of agrochemical inputs can improve soil health

• GMOs can pose a possible solution to to problems associated with industrial farming

• Case Study: Drinking Tea in a Healthier Environment

• Tea, while having a reputation of being healthy, is actually subject to extensive use of synthetic pesticides

• This practice has harmed beneficial pest predators and pest parasitoids 

• Resulted in pest outbreaks 

• Pest damage decreases marketability

• Leads to significant crop loss and further pesticide use

• Regulating bodies and organizations have prescribed limits on pesticides 

• China in response, reduced the use of pesticides through 

• Biodiversity 

• Cover crops

• Yellow sticky cards

• Volatiles which attract pest enemies

• Case Study: But What About Fertilizers?

• Chemical fertilizers

• Inorganic fertilizers made mainly of petroleum or rock

• Offer readily available nutrients 

• Can lead to soil and water pollution

• Organic fertilizers

• Organic alternative to chemical fertilizers

• Offers nutrients in their natural form

• Examples include 

• Manure

• Animal waste 

• Compost

• Food waste, organic litter, and other garden waste

• Different from inorganic fertilizers in that 

• Organic matter in organic fertilizers retains water and nutrients and prevent soil erosion

• Nutrients are released over time 

• Biodegradable: little to no risk of toxic accumulation 

• Drawback is that in order to breakdown the organic matter, microorganisms require warm, moist soil

• Agrominerals 

• Naturally occurring fertilizer found around the world

• Rocks and minerals that contain beneficial plant nutrients

• Composed of 

• Potassium salts 

• Important in root development 

• Needed for composition of plant DNA and RNA

• Phosphorus-containing rocks

• Necessary for enzyme activation 

• Required for withstanding extreme temperatures or droughts

• Silicates and carbonate rocks

• Limestone and dolostone 

• Carbonite sold as limiting agent to increase soil pH 

• Possibly good fertilizer option

Environmental Sustainability Research Centre (ESRC). (2017). Sustainable agriculture, in Environmental sustainability 

in practice. http://brockuesrc.ca/environmental-sustainability-in-practice/sustainable-agriculture