Influence of lime and farm yard manure

4.1.2 Organic matter

The organic matter content on experimental site varies from 5.585% to 5.672%, and 5.46% to 6.9%, respectively before and after experiment. According to MUTWEWINGABO and RUTUNGA (1987), the soil is classified into «humic soils».

The figure below shows the variation of organic matter according to treatments:

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Figure : Organic matter content before and after experiment.

From the figure above, it is observed that the organic matter content has depleted in treatments T₀, T4, T₅ and T₆ while it has increased for T₁, T₂ and T₃. The ANOVA table below shows whether the difference observed between treatments is significant.

Table : ANOVA table for soil organic matter after experiment

Source of variation	DF	SS	MS	F.Observed	F.Table at 1%
Total	27	4.293	0.159	-	-
Block.	3	0.0818	0.0272	0.83	5.09
Treatment.	6	3.623	0.603	24.23	4.01
Error	18	0.5882	0.0326	-	-

CV %= 6.88

The ANOVA table below shows that the difference between treatments is significant at 1% threshold as the value of calculated F is greater than the value of table at 1% threshold. The difference observed between blocks is not significant as the F ratio is lower than the value of F .table at the same threshold.

Table : Mean separation for soil organic matter observed after experiment

Treatments	Mean in %	Homogeneous group
T3 T2 T1 T4 T0 T5 T6	6.9 6.64 6.2 5.52 5.52 5.5 5.46	A A A B B B B

Referring to the above mean separation table, all treatments are classified into two groups where T₃, T₂ and T₁ are into group A while T₄, T₅, T₆ and T₀ are classified into group B. From these, it is clear that treatments within which organic matter (FYM) has been applied result in improvement of soil organic matter and this varies according to the amount applied.

The depletion of organic matter in T₀ is due to the loss by mineralization(little a bite) and leaching by rainfall while in T₄,T₅ and T₆,in addition to leaching due to rainfall, the increase in pH (figure 4 and 5) has influenced the microbial activity in terms of organic matter decomposition and mineralization(RAYAR,2000). The increase in organic matter content for T₁, T₂ and T₃ is caused by the addition of FYM and it increases as the added manure increases.

4.1.3 Total Nitrogen

The total Nitrogen content varies from 0.270%to 0.2836% and 0.269% to 0.339%, respectively before and after experiment. This classifies the soil N content in «very low» range» to «low «range (ANONYME, 1991).

The figure below indicates the variation of Nitrogen according to treatments:

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Figure : Variation of Nitrogen content according to treatments before and after experiment

From the figure above, there has been Nitrogen depletion for T₀, T₄, T₅ and T₆ while an increase in nitrogen content is observed in T₁, T₂, and T₃. The ANOVA table below shows whether the observed difference is significant.

Table : ANOVA table for total nitrogen

Source of variation	DF	SS	MS	F .Observed	F. Table
Total	27	0.013	0.00048	-	-
Block	3	0.000615	0.000205	1.86	5.09
Treatment	6	0.0104	0.0017	15.07	4.01
Error	18	0.0020	0.000116	-	-

CV %= 3.22

From the ANOVA table above, it is observed that there is a significant difference between treatments at 1% threshold as the value of calculated F is greater than the value of F table at 1%threshold. The difference observed between blocks is not significant as the F ratio is lower than the value of F .table at the same threshold.

Table : Mean separation for Total soil Nitrogen observed after experiment

Treatments	Mean in %	Homogeneous group
T 3 T2 T1 T0 T4 T6 T5	0.339 0.320 0.29 0.276 0.270 0.270 0.269	A AB BC C D D D

From mean separation table, the total soil nitrogen observed after harvesting are classified into 5 homogenous groups and treatments which have received organic matter prove to results in better improvement of soil into total nitrogen compare to T4, T5, T6 and T0 where no organic material had been applied (Rayar,2000).

The decrease of nitrogen in those treatments is due to plant up take, leaching by rainfall water and depletion of depletion of organic matter by the causes mentioned early. The increase in Nitrogen for the remaining treatments is due to the addition of FYM, which contains a certain quantity of Nitrogen (Raymond, 1990).