ing. If it is grim, one can look for ways to ameliorate the grimness. And the general result of our studies in the civil defense area show that when thought and effort are applied much can be done. What usually happens when we look at some large-scale problem relating to a nuclear attack on the United States is an overwhelming feeling of hopelessness and pessimism regarding its solution. However, as we break the problem down and study its component parts we usually find them manageable if we are willing to do what is necessary. Some aspects of a problem are shown to be unimportant while others present difficulties which must be resolved, either by research or by application of already available knowledge. FIRE DAMAGE AND ECOLOGY The first discussion of large-scale fire from an ecological point of view was in the testimony of Dr. Wolfe, previously mentioned. It was very pessimistic for at least two reasons. No attention was directed to preventive action. Actually, the testimony did not call for that. It was a direct response to that particular level of attack that the committee investigated. It also lacks serious quantitive attention to the expected initiation and spread of fires. Dr. Hill will address this committee concerning his study regarding this problem. Whatever the final expectation from fire damage would be today, the possibility of preventive action should be assessed. It is certainly conceivable that large firebreaks could be created by planned cutting during commercial logging operations. Forest management, in other ways, might contribute to limiting damage. Fire is the main factor responsible for perpetuation and maintenance of longleaf pine and controlled fires are used in forest management. The use of fire on the prairies in the interests of agricultural productivity was practiced by the Indians. And forestry management also suggests that light surface fires reduce the danger of severe crown fires by reducing combustible litter. Thus we get a glimpse of the need for research on fires as well as grassland and forest practices which might effectively limit damage and favor recovery of these areas to their natural state. RECOVERY OF DAMAGED LAND When areas are severely damaged, whether or not they come back naturally depends in part on the degree of damage and the subsequent chain of events. A local area of exemplary interest is the Copper Basin of Tennessee, where fumes from a copper smelter have killed all rooted plants over a large area. Attempts to reforest this area have not yet succeeded. The erosion and the accompanying changes in the microclimate of the area have combined with the originally destructive forces to create a desert where the land has become too hostile for even artificial reconstruction by conventional techniques. (See fig. M-1, p. 334.) That was a completely forested green area, and it is now absolute desert. It is thus possible to allow destructive processes to proceed to a point of no return unless one envisages Herculean attempts at reconstruction. One hopes that the United States will prepare itself to prevent this from happening over most, if not all, of the productive land which may be damaged in a nuclear war. THE DUST BOWL However, we should not overestimate the vulnerability of ecological systems. The drought of the thirties in the United States created a dust bowl in the Middle West. The extreme lack of moisture, dust, and erosion killed off much of the plant cover. Overgrazing and grasshoppers added to the destruction of plant life. The first chart will show the extent of this damage. Over a period of years, the destruction on the overgrazed land went down almost to zero. And then it stayed until about 1940 or so at a very low level, and then when the moisture and other conditions became proper, it recovered back to its normal coverage in a rather short period of time. The blue line here represents the ungrazed land and the grey line, the moderately grazed. In all cases, it went down to less than 25 percent of the normal cover. This is the extent of damage over a large area which we may equate with the kind of picture that might be drawn following a thermonuclear attack. The loss of ground cover over a period of 8 years was recouped fairly well in a short period of time when proper moisture conditions again prevailed. This is an excellent example of large-area recovery on a natural basis after considerable damage. (See fig. M-2, p. 336.) FIGURE M-2.-DECREASE IN PERCENTAGE OF BASAL COVER IN THE SHORT-GRASS TYPE DUBING DROUGHT AND INCREASE DURING RECOVERY AFTER DROUGHT We might mention here that much work is being done to assist natural processes in the recovery effort. There is an interesting project on the use of the airplane for reseeding depleted and burned out areas of range land. This is a fast method and can be used for covering large areas but further research on materials and methods is needed. Work on the improvement of brushland is also germane to our problem. Some of these methods actually start with fire. Then clearing, artificial seeding, fertilizing, and grazing management are brought into play. It is possible to establish a rich grassy surface of land in 4 to 5 months. Such an area can be so managed that it will be highly productive for 3 to 5 years. After that, the soil will have become sufficiently enriched to support heavy crops of grain, etc. Along with the reestablishment of rangeland it will be necessary to replenish livestock. Some of the requirements for this are: (1) Specialized breeding farms. (2) Veterinary services. (3) Education of farmers. Reforestation can also be artificially augmented. And there is a wealth of information on this subject which should be brought to bear on our problem of reconstruction in the postattack environment. Our own Forestry Service has a good deal of information and one of the most dramatic things going on in the world today is the Israel Government's attempts to reforest the destroyed lands in Israel, land that actually has been uncultivatable for centuries, which at one time consisted of forests. What seems to come out of all this is that an inventory and research effort in the "biological economy" sector should be instituted at a level of intensity comparable to that going on in the industrial economy (from the postattack recuperation point of view). The resources of the agricultural bureaus of Federal and State Governments, as well as academic departments in universities and agricultural schools, undoubtedly contain information and personnel which could be brought to bear on the problems of concern to us. The Department of the Interior, the Forestry Service and the Army Corps of Engineers are still other agencies whose knowledge and skill should be utilized for study of the problems involved. RADIATION EFFECTS ON THE ENVIRONMENT Two problems are raised by the presence of radioactive material in an environment. There is the direct effect on individuals and populations and the total effect will depend upon the total response of the ecosystem. The second problem relates to the passage and concentration of particular isotopes through food chains leading to selective hazards to man and possibly to particular organisms of vital interest to the human economy. Natural radiation interacts with biological material and in one way or another (for example, mutation effects) is an integral part of the equilibrium of life, whether of one generation or of all evolutionary history. The levels of radiation we will be concerned with in the postattack environment will far exceed these natural radiations for some limited period of time, and new responses will appear at these higher levels. Whether or not radiation will create ecological problems will depend upon the level of radiation in an area and the relative sensitivities of living forms in any particular ecosystem. There is a tremendous range of radiation dose which encompasses phenomena of ecological interest. (See fig. M−3.) FIGURE M-3.-DOSE RANGE IN ROENTGENS FOR EFFECTS OF POSSIBLE ECOLOGICAL Mammals. Insects-- Seed plants.. Bacteria_ SIGNIFICANCE 50-1,000+ 200-100, 000+ 300-50,000+ 1, 000-1, 000, 000+ |