SOME ANALYSIS OF SOILS AND FERTILIZERS RELATED TO AGRICULTURE

摘要

The following five Notes,(1)to(5),are being placed one after another In a collected form for the convenience of the readers.Preparation of hydrochloric acid and extract:Weigh 10 g from 2 mm sieve soil sample in a silica dish.Remove the moisture by keeping in an air oven for six hours at 105.After cooling for half an hour weigh.The difference in weight X 10 gives moisture percentage on a dry basis.The above dish is heated on a flame till the soil becomes reddish brown or grayish brown.Stir the sample after an interval of half an hour with a nickel rod.In case the soil is calcarious,it is moistened with a saturated solution of ammonium carbonate.Evaporate the surplus ammonium carbonate on a water bath and finally heated on a sand bath till all the white crust of(NH_4)_2CO_8 disappears.The dish is cooled in a dessicator and weigh and find out the percentage of loss on ignition.