PART X — ENVIRONMENTAL CONTAMINANTS 



for aerobiology to derive out of that 

 association help in developing a theo- 

 retical framework based on ecological 

 systems approaches. 



A planet-wide network for moni- 

 toring ecological systems is clearly 

 essential to the human welfare. We 

 need both warning systems that will 

 permit measures for reducing or 

 avoiding injury to ecological systems, 

 and prediction capabilities wherein 

 the potential for injury is shunted 

 aside or eliminated before risk of in- 

 jury arises. These will inexorably re- 

 quire baseline data against which to 

 measure change, which suggests that 

 we should establish monitoring sta- 

 tions immediately. 



One of the most feasible systems to 

 begin with is one for monitoring ma- 

 terials in the atmosphere. Much of 

 the technology for sampling gases and 

 particles in the atmosphere is at a 

 stage of acceptable reliability, and 

 basic stations and networks already 

 exist for observing and measuring 

 fundamental physical parameters. Ex- 

 tensive and costly efforts are already 

 applied to counteract the diseases of 

 plants and animals by airborne agents, 

 human allergies resulting from air- 

 borne materials, and insect pests car- 

 ried on winds. 



The necessary data base is less well 

 ordered, however. There is an abund- 

 ance of information about spores of 

 common plant-disease fungi (smuts, 

 rusts, and the like), and there is a 

 considerable literature on atmospheric 

 pollen sampled by allergists and paly- 

 nologists. But only scattered studies 

 of other particles of biological origin 

 have been done, and the information 

 on biological particles in general is in 

 an almost completely unordered state. 

 Some good survey data exist on radio- 

 nuclide particle fallout, but only scat- 

 tered data of widely different relia- 

 bilities concerning other inorganic 

 particulates. Local observations on 

 certain polluting gases have been 

 faithfully recorded for ten years or 

 more in some cities, but the informa- 

 tion is mostly uncorrelated with ob- 

 serving stations in other cities or with 



other phenomena. In short, virtually 

 all of the data on dispersal of biologi- 

 cally significant materials in the at- 

 mosphere is unordered, and there is 

 no data system prepared to receive, 

 let alone store and retrieve it. 



By contrast, meteorological data are 

 well ordered and handled in the 

 framework of systems analysis guided 

 by adaptable theory. Furthermore, as 

 consequences of the several Interna- 

 tional Geophysical Years and agencies 

 such as the World Meteorological Or- 

 ganization, meteorology is organized 

 on a worldwide basis. The aerobiolo- 

 gists can profitably take some cues 

 from the meteorologists. 



There follow comments on six ma- 

 jor problem areas of aerobiology — 

 the systems approach, plant and ani- 

 mal diseases, airborne allergens, ur- 

 ban and indoor environments, insects 

 and other microfauna, and phytoge- 

 ography and genecology of "aerial 

 plankton." A concluding section 

 treats the current efforts in aerobi- 

 ology and prospects for the future of 

 the science. 



Systems Approach to Aerobiology 



There is abundant information on 

 movements of biological materials 

 through the atmosphere. Nearly all 

 attention to this topic has been ad hoc 

 and empirical, however. The time has 

 come when the aerobiologist, the me- 

 teorologist, and the applied biologist 

 (e.g., agronomist, forester) or engineer 

 (e.g., sanitation officer, industrial de- 

 signer) should work together system- 

 atically on problems of predicting the 

 time, place, and probability of deposi- 

 tion of given material from the atmos- 

 phere. The objective should be to 

 develop functional models of the mul- 

 tiple-parameter problem of the entire 

 process — particle formation, release, 

 takeoff, aerial trajectory, scavenging 

 or deposition, germination (if viable), 

 and effect on biota or environment — 

 so that prediction is based on all ob- 

 servable parameters, with standard- 

 ized criteria for observations and 

 measurements. (See Figure X-7) 



Development of such models will 

 provide schemes for ordering existing 

 information and storing new informa- 

 tion in a re-usable and retrievable 

 form. If the models are to have con- 

 tinued and improving usefulness, they 

 must also be suited to feedback cor- 

 rections so that new information and 

 new solutions improve the validity of 

 the models. 



Research Needs — This is a diffi- 

 cult set of theoretical and technical 

 problems from the standpoint of both 

 biology and meteorology. Continued 

 and intensified study of the biology of 

 spore formation and release, ques- 

 tions of survival of living material 

 under different atmospheric condi- 

 tions, problems of host specificity and 

 conditions favoring epidemics, and 

 similar matters are needed. From the 

 meteorological standpoint there is 

 need for development of joint prob- 

 ability meteorological statistics con- 

 nected with the favorable conditions 

 for spore release, quantitative trans- 

 port, and the optimum infection 

 "climate." 



Recent advances in measurements 

 of the planetary boundary layer and, 

 in particular, the wind, temperature, 

 and humidity profiles in the near sur- 

 face layer promise to permit estimates 

 of the critical parameters both from 

 direct measurements and inferences 

 from large-scale meteorology. Espe- 

 cially promising is the development 

 of numerical prediction models from 

 which three-dimensional trajectories 

 of material can be calculated; the 

 direction and speed of transport of 

 the material can be forecast 72 to 96 

 hours in advance with steadily im- 

 proving accuracy. 



In the absence of current studies to 

 evaluate the frequency of favorable 

 conditions and the subsequent occur- 

 rences or non-occurrences of infec- 

 tions, the ability of a total biological- 

 meteorological-agricultural warning 

 system to provide usable and depend- 

 able predictions remains to be deter- 

 mined. Contributions toward solving 

 these general problems are increasing. 



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