Dec., I913
T H E J O U R N A L O F I N D U S T R I A L A N D ELVGINEERING CHE-WISTRY
fact t h a t t h e finer particles of soils such as would be carried b y stream waters are high i n potash, phosphoric acid, lime, organic m a t t e r , etc. BUREAUO F S O I L S U. S. DEPT. AGRIC., WASHINGTON
ESTIMATION OF THE LIME REQUIREMENT OF SOILS' BY J. A. BWZELLAND
'r. .I
LYON
Several methods have been proposed for t h e estimation of soil acidity, b u t none is entirely satisfactory. T h e difficulty is t h a t t h e t r u e n a t u r e of t h e acidity is not understood. T h e problem is further complicated b y t h e fact t h a t lime m a y be beneficial t o a soil i n other ways t h a n b y simply correcting a n acid condition. T h e nearest approach t o a quantitative determination of t h e lime requirement of a soil, therefore, would seem t o be a n estimation of t h e t o t a l absorptive power of t h a t soil for lime. This is t h e principle upon which t h e well-known method proposed b y Yeitch* is based. T h e most serious objection t o this method from t h e analyst's standpoint is t h e large n u m b e r of determinations which must frequently be made before t h e alkaline point is reached. T h e writers have also frequently found i t difficult a n d sometimes almost impossible t o determine t h e saturation point. This is t r u e particularly oi soils containing a large q u a n t i t y of organic m a t t e r yielding highly colored extracts, a n d of those containing a large percentage of clay. M a n y clay soils will n o t settle sufficiently, el-en after very long standing, a n d the clay particles in such cases are so fine as t o defy filtration b y t h e ordinary methods. With a view t o overcoming these difficulties t h e writers have examined a method described by R. Albert3 a n d propose certain modifications which seem t o render i t suitable for estimating t h e lime requirement of soils. I n brief, t h e method as proposed b y Albert is as follows: To 2 j grams of air-dried soil a d d 2 0 0 cc. boiled distil'ed water, j o cc. of a s t a n d a r d solution of barium hydroxide, a n d j grams solid ammonium chloride. Distil t h e mixture! collecting t h e a m monia formed in tenth-normal acid. T h e a m o u n t of ammonia found i n t h e distillate is assumed to be proportional t o t h e free barium hydroxide not required t o saturate t h e soil. Barium hydroxide was found TABLE I-LIME Lab. No. 2333 2619 2620 262 1 2622 2623 2624 2625
REQCIREMENT CALCULATED A S C.40. P A R T S PER b ~ I L L I O N DRYSOIL Veitch Albert Veitch Albert method Lab. No. method method method 0 0 930 2626 1500 900 0 67 3749 1100 0 0 24 3750 1100 0 0 0 3751 i00 900 134 0 3752 0 156 3753 1400 560 1 100 1000 0 201 3754 1000 5 00 0 0 3755 900
preferable t o calcium hydroxide, since t h e latter seems t o form with t h e soil certain easily decomposed compounds which effect decomposition of a m m o n i u m chloride. Paper presented a t the 48th meeting of the A . C. S., Rochester, September 8-12, 1913. 2 J . A m . Chem. SOC.,24, 1120. Z. angew. Chem., 1, 533.
IO1 I
This method was compared with t h e Veitch method on a number of samples of soil a n d subsoil of t h e Dunkirk clay loam t y p e , obtained from t h e experiment field. T h e results are given in Table I . T h e results b y t h e t w o methods were widely differe n t , a n d in view of t h e field results obtained b y t h e use of lime an this soil, indicated t h a t t h e figures obtained b y t h e Albert method were much t o o low. This discrepancy appears t o be due chiefly t o t w o factors which apparently were not recognized b y t h e author. I n t h e first place solid ammonium chloride undergoes slight decomposition when boiled with water, a n d appreciable quantities of ammonia are given off. When boiled with some soils ammonium chloride gives u p enough ammonia t o very materially affect t h e results, rendering t h e figures for acidity much t o o low. T h e a m o u n t of ammonia given off was diRerent for each soil. Twenty-five samples were examined a n d t h e ammonia formed expressed in equivalent of tenth-normal acid varied from 0.4 cc. t o j . 6 cc. It becomes necessary, therefore, t o determine this factor for each soil a n d t o make a correction accordingly. T h e second error consists in assuming t h a t t h e absorption of barium hydroxide is immediate. This assumption was found t o be incorrect. I t was found t h a t fixation of barium hydroxide b y a soil was complete when t h e mixture mas heated i n a water b a t h for one hour a t t h e temperature of boiling water. T h e effect of this t r e a t m e n t is shown in t h e following table: TABLE11-BARIUM HYDROXIDE~BSORBEDEXPRESSED AS
I,I'*IE (CAO).
PARTS PER MILLION DRY SOIL
Lab. No. 2619 2620 2623 2624
Absorbed immediately
Ahsorbed during one-hour standing in boiling water
425 425 403 425
9 63 940 1187 896
Absorbed immediLab. 5-0. ately 3i4Y 37.i2
3i54 3755
313 515 268 224
Absorbed during one-hour standing in boiling water 694 1209 985 i61
T h e higher figures obtained b y t h e longer contact of t h e b a r i u m hydroxide a n d soil might be ascribed t o t h e removal of t h e base from solution b y t h e carbon dioxide of t h e air, in which case t h e longer exposure would introduce a n error. T o test this point jo CC. of t h e s t a n d a r d barium hydroxide solution a n d jo cc. of water were placed i n a j o o cc. Kjeldahl flask. T h e unstoppered flask mas t h e n placed i n a water b a t h maintained ai; t h e boiling temperature a n d allonTed t o remain one hour. T h e flask was t h e n removed, ~ j cc. o water a n d j grams solid ammonium chloride added, a n d t h e mixture distilled in t h e ordinary Kjeldah1 a p p a r a t u s with t h e following results : Ammonia expressed in equivalent of S , 10 acid Cc. 5 1 .4 50 cc. barium hydroxide 5 grams ammonium chloride. . . . 5 grams ammonium chloride.. . , , . , , , , , . , , , , , , . , , . , . . . . . . 1.6 Formed b y barium hydroxide., . , . , , , . , . . . . , . . . . . . . . . . . , . 49.8
+
As direct titration of jo cc. barium hydroxide u n -
T H E J O U R N A L OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y
IO1 2
exposed required jo cc. of t h e tenth-normal acid, i t is evident t h a t t h e one-hour exposure does not introduce a n appreciable error. I n view of t h e foregoing results, t h e writers propose t h e following modification of t h e Albert method: T h e air-dried soil is prepared according t o t h e method of t h e Association of Official Agricultural Chemists.’ Place 2 j grams of t h e soil in a Jena Kjeldahl flask. Cover with jo cc. boiled distilled water a n d a d d 50 cc. tenth-normal hydroxide solution. Digest in a briskly boiling water b a t h for one hour with occasional shaking. Remove from t h e water b a t h , a d d 1 5 0 cc. distilled water a n d 5 grams solid ammonium chloride. Connect t h e flask with a nitrogen distillation apparatus, a n d distil. Collect t h e distillate ( 1 5 0 cc.) in tenthnormal acid a n d t i t r a t e , using methyl orange as indicator. T h e strength of t h e barium hydroxide is determined by titrating directly j o cc. of t h e solution, using methyl orange as indicator. The difference between t h e two titrations, therefore, represents t h e amount of barium hydroxide absorbed by t h e soil. T h e soil has a slight decomposition effect on t h e ammonium chloride. It is necessary t o correct for this in each case b y distillation of 2 j grams of soil with j grams ammonium chloride, omitting t h e barium hydroxide solution. T h e ordinary Kjeldahl apparatus may be used, b u t care must be taken t h a t stoppers a n d connections are free from alkali, which may have been left from previous use in t h e ordinary Kjeldahl distillations. This method has been compared with t h e Veitch method on several samples of different types of soil a n d t h e results are given in t h e following table: TABLE111-LIME t a b . No. 2619 2620 2621 2623 2624 2625 3749 3752 3754 3755 15405 15407 15409 15413 15425 15427 15430 15432 15443 15445 15449 13151
REQUIREMENTCALCULATED AS MILLION DnY SOIL
Description of soil Dunkirk clay Dunkirk clay Dunkirk clay Dunkirk clay Dunkirk clay Dunkirk clay Dunkirk clay Dunkirk clay Dunkirk clay Dunkirk clay Volusia loam
CAO.
PARTSPER
Modified Albert
Veitch
loam. . . . . . . . . . . . . . . . . . . . 1100 loam. . . . . . . . . . . . . . . . . . . . 1100 700 loam.. , , 1100 loam. . . . l o a m . . . . . . . . . . . . . . . . . . . . 1000 l o a m . . . . . . . . . . . . . . . . . . . . 900 l o a m . , . . . . . . . . . . . . . . . . . . 900 loam.. . . . . . . . . . . . . . . . . . . 900 loam.. . . . . . . . . . . . . . . . . . .1000 loam.. 500
..
..
..................
Volusia loam.. ....................... 1434 Volusia l o a m . . ....................... 1434 Volusia silt l o a m . , . . . . . . . Volusia silt l o a m . . . . . . . . . . . . . . . . . . . . . . 2390 1673 Volusia silt l o a m . . .................... 2629 Volusia silt l o a m . . .................... Dunkirk clay l o a m . . . . . . . . . . . . . . . . . . . . 1673 Dunkirk clay loam . . , . . 717 Dunkirk clay loam. . . . . . . . . . . . . . . . . . . 1195 Volusia silt loam. ..................... 1195
.
963 940 694 1187 896 694 694 1290 985 761 1836 1321 1749 1344 2531 2620 2307 2352 1768 1232 1456 1344
The results obtained by t h e new method agree very well with those obtained by t h e Veitch method, a n d since there is no apparent method of standardizing either, it may be assumed t o be just as correct. T h e new method possesses t h e great advantage of rapidity, and if t h e details are carefully observed, i t is very easy t o obtain concordant results. N. ‘II. STATE COLLEGE O F AGRICULTURE CORNELLUWIVERSITY, ITHACA 1 U. S. Dept. of Agric., Bureau of Chemistry, Bull. 107, 14.
Vol. 5 , No. I 2
AN INTERESTING SOIL WATER QUESTION IN BRITISH GUIANA By MAURICE BIRD^ Received September 15, 1913
Some years ago, Harrison2 first called attention t o t h e markedly alkaline condition of t h e soil water underlying t h e sugar estates fringing t h e coast of British Guiana, and its pernicious effect upon t h e growth of t h e sugar cane; a n d since this interesting problem is one t o be very appropriately recorded in t h e pages of THIS J O U R N A L , t h e writer has prepared t h e following brief account of it. The appended analyses are typical of t h e sugar soils of British Guiana, a n d indicate their wonderful fertility from a standpoint of plant food. T h e yield a n d quality, however, of t h e cane grown upon t h e m is very often disappointing, a n d this is due t o t h e fact t h a t , many of these lands lying below sea level, deep a n d thorough drainage is well nigh impracticable, with t h e results t h a t as t h e soil slowly a n d continuously decomposes, t h e surrounding a n d underlying water becomes charged with alkaline mineral matter, t h e product of this decomposition, a n d this alkaline material entering through t h e roots, acts in. a very deleterious manner upon t h e juice of t h e cane.
Water a n d volatile m a t t e r . . Insoluble matter
....
Soil from Pln. Albion, Berbice (Coastal estate) 18.050 66.250
0,345 Lime. ....................... 0.629 Magnesia. . . . . . . . . . . . . . . . 0.458 Potash. . . . . . . . . . . . . . . . . . 0.148 S o d a . . ....................... Phosphoric a c i d . . . . . . . . . . . . . . . 0.248 Nitrogen.. . . . . . . . . . . . . . . . . . . . 0.172 NOTE-Though weighed a s ferric oxide is in the ferrous form.
Soil Soil from Pln. from Pln. Hampton Court, Friends, Berbice Essequibo (Coastal (River estate) estate) 19,660 14.503 65.609 66.915 14.503 17.496 0.134 0.316 0.431 0.504 0.495 0.501 0.110 0.112 0.256 0.224 0.351 0.196 some of the iron in these soils
The excess of magnesia over lime in t h e above is very noticeable, and this appears t o be t h e case throughout in t h e alluvial soils of t h e colony. Coming now t o t h e soil waters, t h e writer examined a great many under varying conditions of rainfall etc., finding t h e alkali, a s determined by titrating with decinormal sulfuric acid, t o range from a trace t o 480 parts per million of water, when calculated as sodium carbonate; while t h e total mineral matter, determined by evaporation of t h e water rose t o over one per cent of t h e water. This saline material entering t h e roots of t h e growing cane was found t o produce from three t o five times t h e quantity of ash in t h e juice t h a t is found in t h e juice of cane grown on well drained soils. This ash, or mineral matter, of t h e juice concentrating in t h e molasses from t h e process of t h e sugar factory was found (as so lucidly described by Geerligs)3 t o form uncrystallizable compounds with t h e sucrose, whereby much sugar is lost. I n order t o break up these compounds a n d render t h e sugar available i t becomes’ necessary t o employ some I 2
Chemist t o t h e New Colonial Co., Ltd. West Indian Bullelin, 9, I. 1-39. “Cane Sugar and its Manufacture,” b y H. C. Prinsen Geerligs.
