Competition for nitrogen between plants and soil microorganisms
Experiments suggest that plants and soil microorganisms are both limited by inorganic nitrogen, even on relatively fertile sites. Consequently, plants and soil microorganisms may compete for nitrogen. While past research has focused on competition for inorganic nitrogen, recent studies have found that plants/mycorrhizae during a wide selection of ecosystems can use organic nitrogen. a replacement view of competitive interactions between plants and soil microorganisms is important in ecosystem where plant uptake of organic nitrogen is observed. [1]
Microenvironments of soil microorganisms
Ultrastructural studies of soil micro-organisms and therefore the microenvironments surrounding them are reviewed. Soil microfauna, and bacteria, actinomycetes and fungi, fixed and embedded in place, were examined by microscopy (both transmission and scanning). In some cases ultrastructural histochemistry was wont to detect and identify the organic matter with which microorganisms were associated and to look at the polymeric microbial materials (enzymes, extracellular polysaccharides) they produced. Although some small organisms (0.3 μm diameter) occurred singly in dense fabrics of clay or humified organic matter, larger bacteria occurred in rhizospheres, in small colonies within the larger micropores or related to substantial deposits of organic matter (faecal pellets, carbohydrate-rich plant cell-wall debris). [2]
Soil biological criteria as indicators of soil quality: Soil microorganisms
Diverse soil microbiological studies have attempted to assess deterioration or improvement in soil quality. These studies are done on three levels: population level studies of the dynamics of species that are presumed to be important or sensitive; community level studies of microbial community structure, like species diversity and frequency of occurence of species; and ecosystem level studies of a variety of soil processes. we propose that ecosystem level approaches offer the simplest possibilities for rapidly assessing changes in soil quality. Data from such studies will allow researchers to make a decision whether to proceed with population or community level studies. [3]
Soil microbiomes and climate change
The soil microbiome governs biogeochemical cycling of macronutrients, micronutrients and other elements vital for the expansion of plants and animal life. Understanding and predicting the impact of global climate change on soil microbiomes and therefore the ecosystem services they supply present a grand challenge and major opportunity as we direct our research efforts towards one among the foremost pressing problems facing our planet. during this Review, we explore the present state of data about the impacts of global climate change on soil microorganisms in several climate-sensitive soil ecosystems, also as potential ways in which soil microorganisms are often harnessed to assist mitigate the negative consequences of global climate change. [4]
Evaluation of Crude Oil Biodegradation Potentials of Some Indigenous Soil Microorganisms
This study evaluated the petroleum degradation potentials of some indigenous soil microorganisms. The microbial isolates were among those obtained from petroleum contaminated and uncontaminated agricultural soils of Awoye, Orioke-Iwamimo, Igodan-Lisa and Oba-Ile beat Ondo State, Nigeria. The isolates were tested for petroleum degradation potentials by visual turbidity, extent of breakdown of overlaid oil and therefore the optical density by spectrophotometry method at the wavelength of 540 nm. Brevundimonas diminuta, Bacillus subtilis, Flavobacterium species, Enterobacter species, Klebsiella pneumoniae, Pseudomonas aeruginosa, Alcaligenes faecalis, Bacillus megaterium, Klebsiella edwardsii, Bacillus aryabhattai, Aspergillus flavus, Kodamaea ohmeri, Cephalosporium species, Mucor mucedo, Paecilomyces variotii, Candida parapsilopsis and Trichoderma species were among the sixteen bacterial and 7 fungal isolates tested. [5]
Reference
[1] Kaye, J.P. and Hart, S.C., 1997. Competition for nitrogen between plants and soil microorganisms. Trends in Ecology & Evolution, 12(4), (Web Link)
[2] Foster, R.C., 1988. Microenvironments of soil microorganisms. Biology and fertility of soils, 6(3), (Web Link)
[3] Visser, S. and Parkinson, D., 1992. Soil biological criteria as indicators of soil quality: soil microorganisms. American Journal of Alternative Agriculture, 7(1-2), (Web Link)
[4] Soil microbiomes and climate change
Janet K. Jansson & Kirsten S. Hofmockel
Nature Reviews Microbiology volume 18, (Web Link)
[5] Ikuesan, F. (2017) “Evaluation of Crude Oil Biodegradation Potentials of Some Indigenous Soil Microorganisms”, Journal of Scientific Research and Reports, 13(5), (Web Link)