Bioelectricity of forests ecosystems, wetlands and agro-ecosystems of the Western Ukraine

Abstract

Bioelectricity from ecosystems of living plants and their associated soil electric-generating microorganisms is an innovative source of alternative energy. The bioelectro-productivity of forests ecosystems, marshy areas and agro-ecosystems of orchards and plantations of agricultural crops was assessed in situ in three parts of the Western Ukraine in the north, in the Polissia, in the central part, in the Opillia and in the south, on the border of the Pokutsko-Bukovina Carpathians and Chornogora. The bioelectric potential was determined in the most spread and typical microbial-plant associations of forests, swampy meadows and agro-ecosystems of the Western Ukraine using the two-electrode system, which was located stationary in the soil in the zone of association of the plant root system and electric-generating microorganisms during 150 days - from the beginning of summer to late autumn. The highest rates of bioelectricity were recorded in phyto-microbiocenoses of forests. The average level of bioelectric potential of forests was 1080.5 mV. In the gardens and wetlands, bioelectric performance was slightly lower, 1055.3 mV and 1051.2 mV, respectively. The bioelectric potential of the most agricultural crops was significantly lower, except for the Z. mays crop, which was characterized by high average values of bioelectric potential at the level of garden shrubs. It was found that the daily level of bioelectricity fluctuates slightly with slight decrease at the end of the light day in the some samples. We observed small fluctuations in the parameters of bioelectric potential, because the level of photosynthesis and, accordingly, the degree of accumulation of organic compounds that are substrates for the development of electroactive microorganisms, depending on meteorological conditions, physicochemical soil factors are specific to each ecosystem and each new day. The seasonal fluctuations in the level of bioelectric potential during June – October in the studied microbial-plant associations were statistically insignificant. The influence of humidity on the generation of the bioelectrical potential of phyto-microbocenoses was studied. The positive effect of soil moisture on the bioelectric potential generation was revealed. With increase in humidity of soil from 15% to 55% the level of bioelectric potential of forest and garden microbial-plant associations also increased significantly. The increasing of the bioelectric potential of forest and garden microbial-plant associations of P. silvestris and M. domestica was 159.3 mV and 115.4 mV, respectively in these conditions. The increasing of bioelectric potential in dry soils was determined, due to active photosynthesis and moisture accumulation by plants. With the decrease in humidity of soil from 55% to 25%, the level of bioelectric potential increased significantly in agricultural and garden microbial-plant associations of R. rubrum and B. oleracea, the increase in bioelectric potential was 96.3 and 81.7 mV, respectively. High and stable average values of the bioelectric potential of microbial-plant associations of forests and wetland meadows, orchards and some crops observed for the period from June to October, the rise of potential even in arid conditions were revealed their prospects as an important source of renewable energy. Forests and wetlands, which occupy a significant part of the territory of Western Ukraine, could become an additional environmentally friendly source of energy, both large-scale and local in case of further development of electro-biotechnology.

Keywords

• plants
• soil microorganisms
• soil
• bioelectric potential
• bioelectrochemical energy
• electrodes
• renewable energy