farms that used to grow a variety of crops shifted toward growing only one or two crops that commanded the highest prices; an cause several problems
very high in protein, has a good balance of amino acids, and grows well in mountainous areas
based on crop rotation, reduced soil erosion, integrated pest management, and a minimal use of soil additives
a natural process by which soil is formed, transported, and sometimes lost to a particular ecosystem or region
What is a benefit of crop rotation?
Crop rotation maintains the fertility of a field and helps prevent soil from becoming depleted in mineral nutrients, especially nitrogen.
What is the role of tilling in soil erosion?
By softening and loosening the top layers of soil, it is more easily carried away by water and wind.
Cover crops are _____________.
An IPM, or integrated pest management- system tries to avoid using ___________ on crops.
How can pesticides alter the ecosystem?
The routine use of pesticides can cause adaptations to occur in pests, which can develop a resistance to the pesticide and cause an ecological imbalance.
A negative result of monoculture farming is ____________.
decrease in mineral nutrients in soil
Quinoa is a good alternative to high-yield grains because it _________.
can grow on mountains
Many U.S. farmers have not lost their family farms over the last 40 years because they could not _____________.
afford new machinery
Which country has the most successful integrated pest management system in the world?
The use of machinery and fossil fuels has changed agriculture in the United States. How has the amount of oil used to produce 1 ton of grain changed over 35-year period?
It has doubled.
Compared to farms of 100 years ago, modern agribusinesses need ___________.
In the past, agriculture work was completed by _____________.
humans and animals
Inroduction of natural insect predators is one aspect of _____________.
integrated pest management
Widespread use of pesticides has led to the development of ______________.
more pesticide-resistant insects
Monoculture involves the use of ____________.
genetically identical plants
Drip irrigation provides precise amounts of water directly to crops roots. This method is one of the mainstays of sustainable agriculture because it ________________.
reduces soil erosion
A negative side effect of the mechanization of framing is _________________.
increased fuel costs
Soil erosion can limit the quantity of crops a farmer can produce. Which method can reduce soil erosion?
Monoculture farming often results in ____________.
reduced soil fertility
An IMP system is used to _____________.
Which was likely the most significant cause of the great famine in China between 1959 and 1961?
Resentful farmers refused to work their fields.
Which is not used in integrated pest an management?