Soil nitrogen mineralization and microbial biomass formation in sandy soil amended with labelled leguminous and non-leguminous plant residues [electronic resource].

Includes references.

A lab experiment was conducted to evaluate the effect of different plant residues having varying (C/l'Iil ratios and nitrogen content. Both types of ¹⁵N-labelled plant residues were mixed with a sandy soil and incubated under different rates (0, 50 and 100 mg N Kg⁻¹ soil) at about 22°C for about 10 weeks in a laboratory under aerobic conditions. Results showed that the organic C and CIN ratios decreased with time up to 10 weeks period of incubation at the rate of 50 and 100 mg N Kg⁻¹ soil added as plant residues. but N content increased at any given time until the end of incubation, being followed the order: Soybean> (Wh + Soy) > wheat residues. In general, data showed that the amount of biomass-N gradually increased up to 4 weeks and thereafter, slightly decreased for wheat residues at 50, 100 mg N Kg⁻¹ soil until the end of incubation period. However, the values of biomass-N was as low as 9.44 and 21.85 to as high as 21.22 and 32.27 mg N Kg⁻¹ soil for wheat and soybean residues-treated soil at 50 and 100 mg N Kg-1 soil, respectively. Using ¹⁵N_ technique results indicated that the of ¹⁵N_ mineralization percent for soybean increased overtime-N (narrow CIN ratio) being more effective and sUEerior compared to wheat residue-N (wide CIN ratio) on the net of ¹⁵N-mineralization through out the time of incubation.

Summary in Arabic.

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