Abstract The influence of electrical heating on microbiological processes in soil has been studied to evaluate the potential for enhancing biodegradation of pollutants by controlling the temperature. A frequency of 50 Hz (power line frequency) was applied for resistive heating. Dielectric heating was realized using a frequency of 13.56 MHz (radio frequency). Both techniques were compared with conventional heating in a water bath. For experiments in laboratory and full scale, a model soil and a contaminated original soil were used. It was shown that under conditions capable for heating soil to 35 °C or even 60 °C, soil respiration as a measure for microbial activity was not hindered by electrical heating when temperature and moisture content were comparable with conventional heating. The variations of soil respiration were reversible upon temperature changes. Under certain conditions, periodical fluctuations of microbiological activity were observed. Several possible explanations including chronobiology are discussed without being able to provide an unambiguous interpretation for this effect.

中文翻译：

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低频和高频电加热对土壤中生物降解微生物的影响：土壤呼吸

摘要 研究了电加热对土壤微生物过程的影响，以评估通过控制温度增强污染物生物降解的潜力。50 Hz 的频率（电源线频率）用于电阻加热。使用 13.56 MHz（射频）的频率实现了介电加热。这两种技术都与传统的水浴加热技术进行了比较。对于实验室和全尺寸实验，使用模型土壤和受污染的原始土壤。结果表明，在能够将土壤加热至 35 °C 甚至 60 °C 的条件下，当温度和水分含量与常规加热相当时，作为微生物活动量度的土壤呼吸不受电加热的阻碍。土壤呼吸的变化随温度变化是可逆的。在某些条件下，观察到微生物活动的周期性波动。讨论了包括时间生物学在内的几种可能的解释，但无法对这种影响提供明确的解释。