No abstract

The effect of-freezin,g and duration of storage weeks, after which a prominent decrease ocol lrozen sorl on free amino acids and sugars curred. Essentially there was no difference bewas evalttated. Freez:ing caused a marked in-tween single freeie-thaw and multiple freezecrease rn the total anlount of free amino acids thaw cycles. In general, soil respiiation and an.d-sugar,s extracted, The level of free amino dehydrogenase ac'tivity paralleled^the level of acids and sugars, in frozen soil, remained extracta6le free amino icids and sugars. fairly constant up t,c a storage period of 6

A study was made oI the amount of amide-N (as glutamine and asparagine) in soil miterials by rnethylating the organic mateiial with methanolic-HCl, reducing the resulting product with LiBHr and determining the loss of glutamic and aspartic acidi. The

Five soils were subjecteo ," ,"fi:;ll:Tof 1" ",rd -14"C for 3 ."veeks.Freezing caused a marked increase ln the total amount of free amino acids extracted, The amounts of free amin,: acids released were greater in soils',lhere decomposition of organic mater \var; more complere. wh'ile pror-nged t,or"g" of soil at 1"c had no measurable eiTecr on thc free amino acidi rer""iJ, it"i"[" over a.long period,at -r4'c decreased the free amino acid co'tent.

The free amino acids and the total ninhydrin-reacting material