Chapter 14- ENV 101 Straighterline
"slash and burn" - answerThe history of the development of agriculture has involved
various kinds of innovations. One of the simplest is shifting agriculture, also known as
_________________ agriculture or shifting agriculture.
Shifting agriculture (slash and burn) - answer~In many areas of the world where the
soils are poor and human populations are low, crops can be raised by disturbing small
parts of the ecosystem followed by several years of recovery. The burning of vegetation
releases nutrients that can be used by crops for one or two years before the soil is
exhausted. The return of the natural vegetation prevents erosion and repairs the
damage done by temporary agricultural use.
~While this system of agriculture is successful when human population densities are
low, it is not suitable for large, densely populated areas. When a large amount of the
forest is disturbed and the time between successive uses is decreased, the forest
cannot return and repair the damage done by the previous use of the land, and the
nature of the forest is changed.
polyculture - answerShifting agriculture have been developed over hundreds of years
and often are more effective for their local conditions than other methods of
gardening.these gardens are planted with a mixture of plants, a system known as
__________________. Mixing plants together in a garden often is beneficial, since
shade-requiring species may be helped by taller plants, or nitrogen-fixing legumes may
provide nitrogen for species that require it.
~In addition, mixing species may reduce insect pest problems because some plants
produce molecules that are natural insect repellents.
Native American cultures - answerWhile today we see this form of agriculture practiced
most commonly in tropical areas, it is important to note that many _________________
used shifting agriculture and polyculture in temperate areas.
labor intensive agriculture - answerIn many areas of the world with better soils, more
intense forms of agriculture developed that involved a great deal of manual labor to till,
plant, and harvest the crop.
Three situations favor this kind of farming: (1) when the growing site does not allow for
mechanization, (2) when the kind of crop does not allow it, and (3) when the economic
condition of the people does not allow them to purchase the tools and machines used
for mechanized agriculture. In addition, some crops require such careful handling in
planting, weeding, or harvesting that large amounts of hand labor are required. The
planting of paddy rice and the harvesting of many fruits and vegetables are examples.
,The primary reason for labor- intensive farming is economic. Many densely populated
countries have numerous small farms of 1 to 2 hectares (a hectare is about the size of a
soccer field) that can be effectively managed with human labor, supplemented by that of
draft animals and a few small gasoline-powered engines.
The cost of labor is also low, which encourages the use of hand labor.
Large parts of the developing world fit into this category, including much of Africa, many
areas in Central and South America, and many areas in Asia. In countries such as
China and India, which have a combined population of over 2 billion people, about 70
percent of the population is rural.
Horse-drawn farm implements - answerand the subsequent development of tractors led
to the modern mechanized agriculture typical of North America, much of Europe, and
other parts of the world where money and land are available to support this form of
agriculture.
monoculture - answerMechanization requires large expanses of fairly level land for the
machines to operate effectively. In addition, large tracts of land must be planted in the
same crop for efficient planting, cultivating, and harvesting, a practice known as
_____________________. Small sections of land with many kinds of crops require
many changes of farm machinery, which takes time. Also, many crops interspersed with
each other reduces the efficiency of farming operations because farmers must skip
parts of the field, which increases travel time and uses expensive fuel
~ When large tracts of land are prepared for planting, they are often left uncovered by
vegetation, and soil erosion increases. Because of problems with erosion, many farmers
are now using methods that reduce the time the fields are left bare
~Mechanized farming has removed much of the organic matter each year when the
crop was harvested. This tended to reduce the soil organic matter. As agricultural
scientists and farmers have recognized the need to improve the organic matter content
of soils, many farmers have been leaving increased amounts of organic matter after
harvest, or they specifically plant a crop that is later plowed under to increase the soil's
organic content.
~To ensure that a crop can be planted, tended, and harvested efficiently by machines,
farmers rely on seeds that are identical genetically and thus provide uniform plants with
characteristics suitable for mechanized farming. These special seeds ca -
answerserious drawbacks of mechanized monoculture
specialize in a few crops - answerBecause farm equipment is expensive, farmers tend
to ___________________________. This means that the same crop may be planted in
the same field several years in a row. Planting the same crop repeatedly encourages
the growth of insect and fungus pest populations because they have a huge food supply
at their disposal.
, amount of food - answerEven though there are problems associated with mechanized,
monoculture agriculture, it has greatly increased the ___________________ available
to the world over the past 100 years. This increase has come about because of
improved varieties of crops, irrigation, better farming methods, the use of agricultural
chemicals, more efficient machines, and the use of energy-intensive as opposed to
labor-intensive technology.
The Green Revolution - answerThroughout the 1950s, 1960s, and 1970s, the
introduction of new plant varieties and farming methods resulted in increased
agricultural production worldwide. This has been called
______________________________.
~Both the developed world, which uses highly mechanized farming methods, and the
developing world, where labor-intensive farming is typical, have benefited from these
advances, and food production has increased significantly.
~Many modern varieties of plants require fertilizer and pesticides that the traditional
varieties they replaced did not need. In addition, many of the crops require higher
amounts of water and increase the demand for irrigation.
~Farmers also have become more dependent on the industries that provide specialized
seeds. When the positives and negatives are balanced, however, the end result is that
food production per hectare has increased.
~This has not solved the world's food problem, however, because the population of the
world continues to increase and more food is needed. - answerDrawbacks of the Green
Revolution
~Food subsidies and trade barriers—Governments like to protect their farmers with
subsidies and trade barriers. Such barriers hinder the development of farming in poorer
nations.
~Higher fuel costs—The increase in the price of fuel adds to the cost of food by making
it more expensive to produce and transport.
~Alternative fuels—Increased energy prices divert crops to alternative fuels. Growing
corn for fuel (and, in many cases, cutting back on wheat production) means less grain
for food.
~Rising demand—The rise in global wealth has meant more demand for higher-quality
food that is more expensive to produce. In India and China, people are eating more
meat. That is a sign of prosperity, but it requires greater supply to sustain. That
problem, which also is the major driver behind rising oil prices, is only going to increase.
- answerLong-term solutions to feeding the world's hungry are complex and are unlikely
to be found without global answers to problems that have been difficult for decades.
These issues include the following: