30 terms

Chapter 11: Producing Enough Food for the World - How Agriculture Depends on Environment

an ecosystem created by agriculture; typically it has low genetic, species, and habitat diversity
production of food from aquatic habitats
cash crop
farm crop grown to be sold or traded rather than used by the farm family
chronic hunger
enough food to stay alive but not enough to have productive & satisfactory lives
crop rotation
the practice of rotating use of different fields from crop to crop each year, to avoid exhausting the soil.
demand-based agriculture
agriculture with production determined by economic demand and limited by that demand rather than by resources
drip irrigation
a method of supplying irrigation water through tubes that literally drip water onto the soil at the base of each plant
a field left unplowed and unseeded without harvesting for at least one growing season
genetically modified crop
crop species modified by genetic egineering to produce higher crop yields, and increased resistance to drought, cold, heat, toxins, plant pests, and disease
green revolution
name attached to post World War II agriculture programs that have led to the development of new strains of crops with higher yield, better resistance to disease, or better ability to grow under poor conditions
a technique of growing plants (without soil) in water containing dissolved nutrients
Law of the Minimum
the concept that the growth or survival of a population is directly related to the life requirement that is in least supply and not to a combination of factors
a crude approximation of a chemical toxicity defined as the does at which 50% of the population dies on exposure
the lack of specific components of food, such as proteins, vitamins, or essential chemical elements
production of food from marine habitats
maximum sustainable yield
the maximum amount of any biological resource that can be harvested indefinitely
agricultural practice of producing or growing one single crop over a wide area
optimum sustainable yield
largest yield of a renewable source that is able to be achieved over a long period without decreasing the ability of the population or the environment in which it is located to support the continuation of this yield level
land where grass and other plants grow and where cattle, sheep, etc. can graze
per-capita demand
the economic demand per person
per-capita food production
the amount of food produced per person
resource-based agriculture
agriculture with production limited by the availability of resources
an animal, such as a cow or sheep, with an elaborate, multicompartmentalized stomach specialized for an herbivorous diet
subsistence crops
a crop grown to be used on the farm where it was raised
synergistic effect
when the change in availability of one resource affects the response of an organism to some other resource
the lack of sufficient calories in available food, so that one has little or no ability to move or work
elements required in large amounts by all living things, these are required in large amount to sustain life; there are 6 most important nutrients: oxygen, carbon, sulfur, hydrogen, nitrogen, phosphorus
chemical elements required in very small amounts by at least some forms of life; such elements include things such as boron, copper, chlorine, iron, manganese, molybdenum, nickel, and zinc
organic farming
producing crops and livestock naturally by using organic fertilizer (manure, legumes, compost) and natural pest control (bugs that eat harmful bugs, plants that repel bugs, and environmental controls such as crop rotation) instead of using commercial inorganic fertilizers and synthetic pesticides and herbicides
land that is not intensively managed and is used for grazing livestock