Subsistence Agriculture

1458 WordsOct 6, 20126 Pages
Question #1 How is intensive subsistence agriculture distinguished from extensive subsistence cropping? Why, in your opinion, have such different land use forms developed in separate areas of the warm, moist tropics? Intensive agriculture is the primary subsistence pattern of large-scale, populous societies. It results in much more food being produced per acre compared to other subsistence patterns. Beginning about 5,000 years ago, the development of intensive farming methods became necessary as the human population grew in some major river valleys to levels beyond the carrying capacity of the environment using horticulture and pastoralism. The transition to intensive agriculture was originally made possible by water management systems…show more content…
The maximum sustainable yield is usually higher than the optimum sustainable yield. This logistic model of growth is produced by a population introduced to a new habitat or with very poor numbers going through a lag phase of slow growth at first. Once it reaches a foothold population it will go through a rapid growth rate that will start to level off once the species approaches carrying capacity. The idea of maximum sustained yield is to decrease population density to the point of highest growth rate possible. This changes the number of the population, but the new number can be maintained indefinitely, ideally. MSY is extensively used for fisheries management. MSY in most modern fisheries models occurs at around 30% of the unexploited population size. This fraction differs among populations depending on the life history of the species and the age-specific selectivity of the fishing method. However, the approach has been widely criticized as ignoring several key factors involved in fisheries management and has led to the devastating collapse of many fisheries. As a simple calculation, it ignores the size and age of the animal being taken, its reproductive status, and it focuses solely on the species in question, ignoring the damage to the ecosystem caused by the designated level of exploitation and the issue of by catch. Question #3 How, in your opinion, do the
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