The Life Sciences Recent Progress and Application to Human Affairs The World of Biological Research Requirements for the Future (1970) / Chapter Skim
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Renewable Resources
Renewable Resources
Pages 195-209
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From page 195... ...
One study comparing the reactions of rats, dogs, and human beings to six standard test drugs revealed many similarities, but of 86 distinct recorded effects, 33 appeared only in man! In the final analysis, after careful and extensive animal experiments have been completed, controlled human trials are imperative to measure the full range of a drug's effects.
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From page 196... ...
The quality of some of our surface waters and groundwaters can be restored, but, with the knowledge currently available to us, the results of pollution can be reversed only at great cost. For example, even if the introduction of fertilizing nutrients is terminated and if the waters of a historically heavily polluted lake can be completely exchanged over a period of time, the enormous amount of harmful matter bound in the bottom mud may continually replenish the pollutant materials.
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From page 197... ...
These conditions can be understood in the light of modern evolutionary theory, which is based on genetic variability and natural selection and provides a satisfactory framework for understanding the diverse characteristics of the biological world. In this area, understanding and appreciation of population genetics is most critically needed.
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From page 198... ...
Environmental Management AGRICULTURE Agriculture has evolved beyond crop culture to become an environmental technology with emphasis on the management of land, water, air, and biological resources for the production of food and fiber and for the preservation of natural resources. The successful farm or ranch is, in fact, a wellregulated ecosystem in which renewable resources are effectively conserved.
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From page 199... ...
The Dust Bowl, involving 100 million acres, was a costly lesson to American agriculture; as a result of it, the Soil Conservation Service was formed in 1935 to devise and encourage sound land-management techniques. Only a small fraction of the Dust Bowl has been returned to production.
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From page 200... ...
The input of biological skill is minimal, and the results range from excellent, as in many of the eastern Canadian spruce fir pulpwood cuttings, to the destruction of the resource. As intensity of management increases, measures such as restricted harvesting, timing of operations, prescribed fire, and thinning are employed to favor reproduction and growth of desired species and reduce competition with less valuable species.
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From page 201... ...
; (b) information about the taxonomy, life histories, and behavior of the species under natural conditions and when confronted with capturing tools (included here are foods; food habits; sensory capacities; territorial or schooling behavior; knowledge of the action, including selectivity, of the capturing gear)
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From page 202... ...
. Furthermore, catch limits can be quickly filled with modern mechanized gear, and this leads to difficulties in keeping vessels and manpower profitably occupied, a problem encountered with the tuna stocks of the Western Pacific.
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From page 203... ...
These plants require enormous quantities of water for cooling, and the low-grade waste heat carried by this water will also be enormous. If, for example, sufficient combined nuclear power and desalting plants were constructed on the West Coast to meet the needs for both fresh water and electric power, the rise in temperature of inshore waters might be as much as 4° F
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From page 204... ...
Management techniques have developed in a historical sequence that began with restrictions on time or methods of taking game, later included predator control and refuges, still later moved to artificial replenishment, and finally incorporated environmental manipulation. Even though knowledge of habitat manipulation is considerable, we still rely on seasonal and bag-limit restrictions as the principal management measures for game species.
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From page 205... ...
Numerous investigations have questioned the wisdom of pursuing traditional statewide predator control programs with little evaluation of either the need for the program or the effectiveness of the control effort. Excessive populations of deer and elk are a nagging problem in national parks and on large military reservations, where hunting cannot be used to achieve population reduction.
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From page 206... ...
Wilderness areas and national parks are good examples in which visitorrecreation problems extend beyond the immediate site being occupied. Although many such areas are more than several hundred thousand acres in size, the direct physical contact of visitors is concentrated on a very few acres.
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From page 207... ...
The number of visitors to our national parks and national recreation areas begins to pose a serious problem (Figure 329. The visitor load in these public areas has increased nearly sixfold in 20 years and in 1968 was 151 million; the number of parks has increased at a much slower pace.
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From page 208... ...
Man's activities in these places change raw materials and natural products into new forms, often resulting in waste products that must somehow be disposed of or recycled. When these waste products reach the air or water or land in forms or concentrations that are detrimental, they are "pollutants." Unacceptable means of waste disposal are the cause of one of the major impacts of man on his environment.
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From page 209... ...
The true costs of any program in the management of renewable resources, be it in industry, agriculture, recreation, health, forestry, fisheries, or urban development, should be evaluated, and decisions should be made, upon the advice of groups of specialists, by representatives of society as a whole, seeking what is best for local, continental, and planetary ecosystems. Only by knowledge and understanding of the function and interaction of the biological and physical elements of the environment and by application of this knowl 209
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