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Biology
Molecular Biology

Variation of Soil Microbial Population in Different Soil Horizons

Profile image of Pandey SunilPandey SunilProfile image of Bishwoyog BhattaraiBishwoyog Bhattarai
https://doi.org/10.15406/JMEN.2015.02.00044
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Abstract

Large diversity of micro flora and fauna are found in soil horizons. Microbial population in soil are determined by various factor such as soil depth, organic matter, porosity, oxygen and carbon dioxide concentration, soil PH, etc. Factors that influence microorganism role in nutrient building and cycling in soil and organic matter decomposition are of unique interest. Microorganisms decompose organic matter, detoxifying the toxic substance, fixing the nitrogen, transformation of nitrogen, phosphorous, potassium and other secondary & micro nutrients are the major biochemical activities performed by microbes in soil. Low population of microorganism is found in the compact soil, soil with low organic matter percentage and on deeper strata of soil. So, this paper was reviewed to explore major factors that influence soil microbial population and its role in soil productivity. This was already established fact but main aim of this paper is to collect related information and conclude the future research prospects to strengthen the microorganism role in soil productivity and factor that influence growth of microorganism.

Figures (4)
Table1: Estimated content of organism in soil.
Table1: Estimated content of organism in soil.
Source: Hoorman and Islam- Ohio State University Table2: Microorganism species at 0-15cm depth of soil. Similarly studies conducted by Fierer et al. [17] have showed the decreasing microorganism population with increasing soil depth (Table 3).
Source: Hoorman and Islam- Ohio State University Table2: Microorganism species at 0-15cm depth of soil. Similarly studies conducted by Fierer et al. [17] have showed the decreasing microorganism population with increasing soil depth (Table 3).
Source: Fierer et al. [17] Table3: Decreasing microorganism population with increasing soil depth.
Source: Fierer et al. [17] Table3: Decreasing microorganism population with increasing soil depth.
Table4: Amount of nitrogen fixed by the different microorganism. Nonsymbiotic association of Azobacter, Clostridium fixes about 5-20 kg N/ha/yr’s and various species of blue green algae fixe: about 10-50 kg N/ha/yr’s [1,26]. Two fungi Aspergillus fumigatus
Table4: Amount of nitrogen fixed by the different microorganism. Nonsymbiotic association of Azobacter, Clostridium fixes about 5-20 kg N/ha/yr’s and various species of blue green algae fixe: about 10-50 kg N/ha/yr’s [1,26]. Two fungi Aspergillus fumigatus

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References (30)

  1. Brady NC, Weil RC (2012) The Nature and Properties of Soils. (14 th edn), Dorling Kindersley India Pvt. Ltd, Noida, India.
  2. Day SD, Bassuk NL (1994) A review of the effects of soil compaction and amelioration treatments on landscape trees. Journal of Arboriculture 20(1): 9-17.
  3. Stine MA, Weil RR (2002) The relationship between soil quality and crop productivity across three tillage systems in south central Honduras. American Journal of Alternative Agriculture 17(1): 2-8.
  4. Onduru DD, Jager AD, Wouters B, Muchena FN, Gachimbi L, et al. (2006) Improving Soil Fertility and Farm Productivity under Intensive Crop-Dairy Smallholdings: Experiences from Farmer Field Schools in the Highlands of Kiambu District, Central Kenya. Middle- East Journal of Scientific Research 1(1): 31-49.
  5. Eilers KG, Debenport S, Anderson S, Fierer N (2012) Digging deeper to find unique microbial communities: The strong effect of depth on the structure of bacterial and archaeal communities in soil. Soil Biology and Biochemistry 50: 58-65.
  6. Hardy J (1990) The rain making bacteria. ASCP, California, USA.
  7. Bourgaize D, Jewell TR, Buiser RG (2004) Biotechnology: Demystifying the concept. (2 nd edn), Persion Education, Delhi, India.
  8. Hoorman JJ, Islam R (2010) Understanding soil microbes and nutrient recycling. Agricultural and natural resource 16(10).
  9. Schmidt SK, Gier MJ (1989) Dynamics of Microbial Populations in Soil: Indigenous Microorganisms Degrading 2,4-Dinitrophenol. Microb Ecol 18(3): 285-296.
  10. Rao NS (2005) Soil Microorganisms and Plant growth. (4 th edn.), Oxford and IBH Publishng Co. Pvt. Ltd, New Delhi, India, pp. 407.
  11. Cocks LRM, Torsvik TH (2002) Earth Geography from 500 to 400 million years ago: Faunal and palaeomagnetic review. J Geol Soc Lond 159: 631-644.
  12. Janusauskaite D, Kadziene G, Auskalniene O (2013) The effect of tillage system on soil microbiota in relation to soil structure. Pol J Environ Stud 22(5): 1387-1391.
  13. Silva AP, Babujia LC, Matsumoto LS, Guimaraes MF, Hungaria M (2013) Bacterial Diversity Under Different Tillage and Crop Rotation Systems in an Oxisol of Southern Brazil. The Open Agriculture Journal 7(Supp 11-M6): 40-47.
  14. Watson GW, Kelsey P (2006) The impact of soil compaction on soil aeration and fine root density of Quercus palustris. Urban Forestry & Urban Greening 4(2): 69-74.
  15. Egamberdieva D, Kamilova F, Validov S, Gafurova L, Kucharova Z, et al. (2008) High incidence of plant growth-stimulating bacteria associated with the rhizosphere of wheat grown on salinated soil in Uzbekistan. Environ Microbiol 10(1): 1-9.
  16. Mandal SN (2013) Brief Introduction to Soil. Department of Agriculture, Lalitpur, Nepal.
  17. Fierer N, Schimel JP, Holden PA (2003) Variation in microbial community composition through two soil depth profile. Soil Biology and Biochemistry 35(1): 167-176.
  18. Collins H (2010) Impacts of Fumigation and Crop Rotation on soil Microbial Populations. USDA-ARS Irrigated Research Center, USA.
  19. Grubinger V (2004) Soil Microbiology: A Primer. University of vermont, Burlington, USA.
  20. Magdoff F, ES VH (2010) Building Soils for Better Crops: Sutainable Soil Management. (3rd edn), Sustainable Agriculture Research and Education, USA, pp. 294.
  21. McNabb DH, Startsev AD (2009) Effects of compaction on aeration and morphology of boreal forest soils in Alberta, Canada. Canadian Journal of Soil Science 89(1): 45-56.
  22. Stier JC (2000) Lawn Aeration and Topdressing. University of Wisconsin-Extension, USA.
  23. Gilman EF, Leone IA, Flower FB (1987) Effect of soil compaction and oxygen content on vertical and horizontal root distribution. J Environ Hort 5(1): 33-36.
  24. Swer H, Dkhar MS, Kayang H (2011) Fungal population and diversity in orginically amended agricultural soils of meghalaya, India. Journal of Organic Systems 6(2): 3-12.
  25. Bhardwaj D, Ansari MW, Sahoo RK, Tuteja N (2014) Biofertilizers function as key player in sustainable agriculture by improving soil fertility, plant tolerance and crop productivity. Microb Cell Fact 13: 66.
  26. Dastager SG, Deepa CK, Pandey A (2010) Isolation and characterization of novel plant growth promoting Micrococcus sp NII-0909 and its interaction with cowpea. Plant Physiol Biochem 48(12): 987-992.
  27. Ogbo FC (2010) Conversion of cassava wastes for biofertilizer production using phosphate solubilizing fungi. Bioresour Technol 101(11): 4120-4124.
  28. Boyle SA, Yarwood RR, Bottomley PJ, Myrold DD (2008) Bacterial and Fungal Contributions to Soil Nitrogen Cycling under Douhlas Fir and Red Alder at two sites on Oregon. Soil Biology and Biochemistry 40(2): 441-451.
  29. Hertage J, Evans EGV, Killington RA (1999) Microbiology in Action. Cambridge University Press, London, UK.
  30. Variation of Soil Microbial Population in Different Soil Horizons 4/4

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