WEDNESDAY, JUNE 24. AFTERNOON SESSION. 



The Fertility of Soils in the Tropics. 



Chairman: SIR SYDNEY OLIVIER, K.C.M.G., Permanent Secre- 

 tary to the Board of Agriculture, formerly Governor of 

 Jamaica. 



THE following papers were read : 



SOME NOTES ON CERTAIN POINTS IN RELATION TO THE 

 PROBLEM OF SOIL FERTILITY IN THE TROPICS. 



By H. A. TEMPANY, B.Sc., F.I.C., F.C.S., 

 Superintendent of Agriculture, Leeward Islands. 



[ABSTRACT.] 



In this paper attention is directed to the importance which 

 biological factors have assumed in relation to considerations of 

 soil fertility. It is pointed out that up to the present time 

 the results available have been arrived at under temperate con- 

 ditions; activities of this description are, however, limited in 

 temperate latitudes by temperature range; the intervention 

 each year of a winter period, during which biological activities 

 in the soil are very greatly reduced if not entirely suspended, 

 constitutes a limiting factor of great importance, which is 

 absent under tropical conditions. In the latter case the pre- 

 valence almost continuously of a set of conditions peculiarly 

 favourable to biological development causes such factors to 

 assume a greatly enhanced degree of importance. 



In the course of the paper data are given showing the tem- 

 perature range occurring in soils in the Leeward Islands 

 Colony, which illustrate the points alluded to above, the tem- 

 perature never falling below 20 C. and very rarely exceeding 



30 c. 



Summarized data are also given showing the rate at which 

 organic matter tends to disappear as the result of bacterial 

 action in soils under these conditions, the amounts lost varying 



