Agriculture
Contributor: Liz Yugov
Crop Rotation
Crop rotation is the practice of “rotating crops,” or sequentially planting different crops on the same plot of land. This rotation improves soil health, optimizes soil nutrients, and combats pests and weeds. Farmers seek to plant consecutive crops that compliment each other. For example, a farmer may choose to plant beans after planting corn because the beans will return nitrogen to the soil that the corn uses up. Rotations can involve as little as two to three crops and as many as over a dozen.
The premise of crop rotation is the idea that different plants have different nutrients they require and are vulnerable to different pathogens and pests. Planting the same crop in the same area year after year, the same nutrients are being used up in the soil. Pests and diseases who thrive off that single crop can make a permanent home because their preferred food is available all the time. Planting the same crop (monoculture) increases the need to use fertilizers and pesticides to keep yields high.
Farmers in Europe have been using crop rotation since its introduction in Holland (region in the Netherlands) and Great Britain in the mid-1700s. Their crop schedules consisted of wheat, barley, a root crop like turnips, and a nitrogen-fixing crop such as clover in rotation. The growth of a nitrogen-fixing crop eliminated the need for a fallow period, or time when no crops were being grown on a plot of land. Farmers would also allow livestock to graze on clover, allowing manure to accumulate, directly improving soil fertility.
Crop rotation reduced in popularity in developed nations in the 1950s in part to the discovery that monoculture (one-crop) fields could produce high yields with the application of fertilizers, pesticides, and weed killers. Modern day large-scale commercial agriculture has an increasing reliance on prescribed chemical treatments. However, the acknowledgments of the effect on human health and soil fertility as has many farmers going back to crop rotation, the “natural” way, although chemicals are still being used. A growing consumer demand for organic goods has farmers avoiding chemicals altogether, and instead relying entirely on crop rotations to maintain production.
Cost-wise, crop rotation is easy to implement because there is no need to buy any technology and by rotating crops, fields are less dependent on chemicals for high yields, which brings down the overall cost. Unfortunately, there is little understanding of crop rotation. This is due to a lack of a global dataset for crop rotation. However, it is known that crops grown in rotation have a 10% higher yield than monocultures and 25% higher during drought season.
Many resources are available to farmers who wish to transition to crop rotation, such as SARE’s Guide to Crop Rotation.
Agricultural practices to increase crop yields: crop rotations, reduce fertilizers…
Whether it has been done before: where/when was it implemented? Was it successful? At what scale? What barriers / challenges does it face?
Whether it is economically viable: does the energy / food / water / emissions savings justify the implementation cost?
Whether it is technically feasible: does the technology already exist? Is it scalable, and if not can it be scaled?
Overall, is it a solution we would recommend for the University / state / country / world?
Is it a solution that we as a student group can help with (at any stage: promotion, design…)?
https://www.dedellseeds.com/resource/9-ways-improve-corn-crop-yields/
Plant at the right time. Perform tests on our soil to see if it is ready for early planting, which may result in increased yields.
Practice crop rotation. Alternate the crop planted in a given season i.e. don’t plant corn in the same field corn was planted the previous season unless soil conditions are strong enough or you don’t have enough land to rotate.
Know the yield potential. Estimate the yield of your crops to manage your expectations and to make sure production is on track.
Scout the fields, checking for soil conditions, any weeds, and that the crops are growing healthy.
Ensure proper water drainage. Crops must get just enough water, not too much, and not too little. An effective drainage system can help prevent waterlogging and salinization of soil.
Use fertilizers for optimal soil conditions with nutrients like potassium, phosphorous, and calcium.
Test the soil. Important to know phosphorus, potassium, and fertilization levels to know which crops to grow, how densely to grow them, and how to tend to them
Weed early and often. Weeds eat up nutrients crops need, so it is important to take care of them as soon as possible
Use high quality seeds. Hybrid seeds grow faster, stronger, and more efficiently, which in turns makes them more productive. Non-GMO seeds are sustainable and more cost efficient.
https://www.scientificamerican.com/article/precision-farming/
Ever growing world population means an ever growing burden on farmers to produce more food
However, there is not enough arable land to account for the growing population
Growing need for large farms to become the most efficient and profitable
Increase yields, reduce waste, remain economically and environmentally sustainable
Traditional farming: planting, harvesting, irrigating, pesticides, and fertilizer decisions based on region and data
Precision farming: using sensors, robots, GPS, mapping tools and data analytics to come up with a care plan for plants without intensive labor
Stationary or robot-mounted sensors
Drones with cameras send images and data on individual plants to computers which run a health report analysis
Can gather information on stem size, leaf shape and moisture of soil
This information is delivered real time and water, pesticide, or fertilizer is given in calculated doses
This technology also helps farmers decide when to plant/harvest crops
This goes along with many of the tips listed above (time management, reduce water and chemical use, produce healthier crops, higher yields) as well as conserve resources and reduce chemical run off
Who is developing the software and sensors needed for precision farming? Monsanto, John Deere, Bayer, Dow and DuPont
Precision farming is supported by The U.S. Department of Agriculture, NASA and the National Oceanic and Atmospheric Administration
College are beginning to offer classes in the topic
Seed producers observing how plants grow in different conditions to develop seeds that are ideal for each specific soil and weather conditions
Precision agriculture is not equally embraced everywhere
Expensive at a large scale
Lack of broadband
Longtime producers will not be as keen to pick up technology
Technology will be out of reach of farms in developing nations
Salah Sukkarieh (University of Sydney) developed a streamlined, low-cost monitoring system in Indonesia that relies on solar power and cell phones
https://ec.europa.eu/environment/integration/research/newsalert/pdf/8na3_en.pdf
Substantial food production increases with more efficient water use, improvement in organic matter accumulation and carbon sequestration, and reduced pesticide use.
Precision agricultures is the most popular option among farmers but is also the most advanced
Agribusiness → maximize profitability
Most successful example: Controlled Traffic Farming (CTF) -- reducing soil damage due to repeated heavy machinery use
Reduce machinery and input costs by up to 75%
Crop yields also increase
Optimize the application of fertilizers and other chemicals
In conventional farming, these are applied uniformly
In PA, these are applied only where needed depending on many factors
In high-value fruit and vegetable crops, precision irrigation methods are developing rapidly in order to save water, increase yields and improve quality
Precision Livestock Farming (PLF) relies on automatic monitoring of individual animals for animal growth, milk and egg production, detection of diseases, and monitoring animal behaviour and their environment
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2613695/
To feed the growing population, either more acres can be used, or existing farmland can be used more effectively
Increasing productivity is the better option because it avoids greenhouse gas emissions and the disruption of ecosystems
The U.S.’s increase in corn yields is from approximately 1.6 tons/ha in the beginning of the 20th century to 9.5 tons/ha today
This is because of the widespread use of technologies like hybrid corn, synthetic fertilizers, and advanced farm machinery
Disposable incomes are rising world wide → increase in meat consumption
Urban China: meat consumption rose from 25 kg/person/year in 1996 to 32 kg/person/year in 2006
Still far below 100 kg/person/year in the United States and countries in Western Europe
Globally over the next decade
Meat consumption is expected to grow by 55 to 310 million tons/year
Corn- and wheat-based biofuel production is expected to grow by 28 to 67 billion liters/year
Feed grain usage (to feed livestock) will have to increase by 50 to 640 million tons/year
Total demand for corn and wheat is expected to increase by about 15% or about 200 million tons/year to a total of 1.5 billion tons/year
Improving yield on farmland will have a lower environmental impact than utilizing new land
Cultivating new acreage requires land clearing and tillage which implies significant greenhouse gas emissions and negative impacts on biodiversity and water quality
However, increasing productivity on existing farmland will also have environmental effects, though less and sometimes even positive
Use of nitrogen fertilizers increases nitrous oxide emissions, reduces water quality, and increases the size of hypoxic zones
Hypoxic zones: low-oxygen areas in bodies of water
Increased use of modern farming practices (especially in developing) countries, with infrastructure, marketing, and risk management tools to support these practices, there could be significant increases in crop production, reducing the need for introducing new land
Rising demand for food → rising crop prices → rising cost for consumers (esp. in poorer)
High crop prices can inscenitize farmers to invest in modern farming technologies to improve yields
Biotechnology: hybrid seeds (such as corn) to increase yields → strong, resistant crops
Can improve grain yield and efficient nitrogen use
Improving drought tolerance is the next challenge
This is helpful to
Increase yield in dry areas
Increase yields of rain-fed fields
Decrease water requirements
