Impact of Extremely Low Frequency Electromagnetic Fields on Soil Arthropods in Nature

Abstract

Study of long-term impact of extremely low frequency, low intensity antenna radiations and electromagnetic fields at the Navy's project Sanguine Wisconsin Test Facility continued in summer, 1973, with population analyses of soil arthropods in 9 test and 6 control plots. In 1973, 13 out of 19 plots and subplots had fewer arthropods than in 1972. The even distribution—7 test and 6 control plots—rules out a Sanguine effect. The 3 main test subplots are spaced 30 yards apart and have similar flora, soil, and exposure; yet between 1972 and 1973, total population doubled in one subplot, halved in another, and remained the same in the third. Control subplots showed similar variability. Evidence for a stabilized micropredator-prey system is the absence of significant differences in proportions of predators (Mesostigmata, Prostigmata) in 7 of 9 test and control pairs, monthly and for the entire summer. In 8 of 11 tests (73%) and 5 of 8 controls (63%) there was also no significant shift in proportions of predators between 1972 and 1973: the 6 significant shifts occurred equally among tests and controls. Predator densities in paired plots monitored for 3 years have not differed significantly. After 4 years of antenna operation, Cryptostigmata:Collembola ratios in test and control plots are roughly the same, and approximate the 1969 pre-treatment ratios. Other data support the hypothesis that 4 years of ELF operation has not Altered soil micro-arthropod population structure near the antenna.