THE INFLUENCE OF POTSHERDS ON NITRIFICA- 

 TION IN THE INDIAN ALLUVIUM. 



By JATINDRA NATH SEN. 

 (Research Station, Pusa, India.) 



(With Four Figures in text.) 



Introduction. 



Nitrogen, one of the most important plant nutrients, is present in the 

 soil mainly as organic compounds which, with certain exceptions, are 

 not, in those forms, assimilable by ordinary cultivated plants. The 

 organic compounds undergo a series of chemical changes before they are 

 ultimately changed into nitrates which are practically the most useful 

 compounds of nitrogen which can be taken up by plants. 



Decomposition of organic materials, however, depends on many 

 factors, one of the most potent of which is the sujjply of air, as oxygen 

 gas is largely used up in some of the reactions involved. Hence the freer 

 the aeration of the soil, the better are the decay and nitrification of the 

 organic matter. Moreover the greater the oxygen available, the more 

 active are the fungi of the soil which collect phosphates and potash for 

 the nourishment of higher plants. It thus follows that the more efficient 

 the soil aeration, the greater is the amount of plant food available. 

 Mr A. Howard, C.I.E., Imperial Economic Botanist, has described the 

 important role that potsherds play as aerating agents and has drawn 

 attention to the various factors determining their practical value in 

 effecting improvements in soils^. Not only do potsherds bring about 

 beneficial bio-chemical effects, but they also improve the physical con- 

 dition of the soil and favour an abundant and rapid development of roots 

 of plants and thus tend to increase the yield of crops. 



• '"Soil Ventilation and Soil Aeration in Agriculture," Agr. Hes. Inst. Pusa. Bull. 52 

 and 61 ; also "The Manurial Value of Potsherds," Agric. Joiini. India, 1910, 11, p. 2oG. 



