It has to be specific set of soil microbes ..since decomposition is primarily routed through microbes ..

Dear Anoop Kumar Srivastava

In this time we will possibly to find correlation between decomposition and microbial activity.

Thank you very much

Meric, infact decomposition involves very strong role of microbes . different native soil microbial communities dominate one over other community at different phases of decomposition . And , there will surely be  strong correlation between microbial  load and rate of decomposition.

Decomposition of Norway spruce and Scots pine needles: Effects of liming (Plant and Soil, February 1996, Volume 179, Issue 1, pp 1–7| )

Abstract: The effect of liming on the decomposition of Norway spruce needle litter was studied in 40–60-year-old Norway spruce stands. Finely-ground limestone had been spread about 30 years ago at a dose of 2 t ha−1 and reliming was carried out about 20 yr later at a dose of 4 t ha−1. Needle litter was collected from both control and limed plots, and it was placed in litter bags in the middle of the humus layer of the plot from which they originated, and similarly to the other plot in May. Litter bags were sampled after 4, 12 and 16 months. The site of origin of the needle litter, whether from control plot or from limed plot, affected mainly the early stages of decomposition. Initially the effect of liming was seen as decreased concentration of water soluble material and then, during decomposition, as decreased mass loss and decreased degradation of lignin, and increased C/N ratio. The incubation site, whether the control or the limed plot, did not affect decomposition significantly.

Decomposition of Scots pine needles in a young Scots pine plantation was also studied. The treatments were: 2 t ha−1 of finely-ground limestone and 2.5 t ha−1 of bark ash spread 8 months before this study. The treatments did not affect decomposition much, but some stimulation of the treatments on decomposition was observed. Compared to spruce needles, the C/N ratio of pine seedles was lower, they contained less lignin and more water soluble material, and decomposed faster in the first summer.

Ecological studies of soil organisms with references to the decomposition of pine needles(Plant and Soil,February 1983, Volume 75, Issue 1, pp 139–151)

Abstract: A study was made of the gut content composition of Porcellio scaber Latr. in the coastal pine sites, and of feeding experiments on naturally occurring needles and artificially treated needles.The gut contents of isopods consisted mainly of fragmentary tissues of needles and subsidiarily of fungal hyphae. The proportion of fungi in the gut varied with the season of the year, the age of isopods and their habitats in relation to fungal density.

The more the decay of needles proceeded, the more the needles were preferred and consumed,i.e. brown needles least, dark brown needles intermediate, and blackish brown and yellowish decayed needles most. Irrespective of considerable differences in food consumption of these needles, assimilation was the same and its efficiency decreased with the progress of decay.As far as the needles in the incipient stages of decay are concerned, the structural toughness of needles is considered to be the prominent factor in determining the feeding value of the needles. Of extractive treatments on natural needles, removals of ether- and water-soluble fractions in all kinds of needles reduced drastically both consumption and assimilation.

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