Composition of the Drainage Water of a Soil With and Without

better as the basis for a study of the influence of vegetation on the removal of mineral matter in the drainage water. In Tables IV and V, the substan...
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T H E I 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 .

742

I S F L U E S C E O F CARIlON U P O X

XITKIFIC.\TIOK.

During the past fifteen years a large number of investigations have been made a t the Station and elsewhere in the state in regard t o methods for the disposal and purification of waste liquors from various industrial plants. During these studies certain results were obtained t h a t caused us t o believe that the activity of the nitrifying organism and the formation o f nitrates were probably dependent upon the relation oi' carbon to nitrogen in the wastes studied. I n order to determine whether or not this belief was true, a large number of special experiments are being made b y us, and while not yet complete, the results so far obtained show that the carbon does have the influence t h a t our observations seemed t o show. A sewage or waste containing, say, z amount of nitrogen will, when submitted t o oxidizing or nitrifying conditions in a filter, fail t o nitrify if there is an amount of carbon equal to IOX. Increasing the amount of nitrogen, however, will enable nitrification to take place, but this nitrification may again be checked b y increasing the carbon. The results of the various investigations along this line will be presented in a subsequent paper. STATE

BOARD O F HEALTH, BOSTON.

COMPOSITION OF THE DRAINAGE WATER OF A SOIL WITH AND WITHOUT VEGETATION. I3y L Y T T L E T O N L Y O N A N D JAMES A . BIZZELL Received July 20, 191 1 .

Drainage water was collected from twelve large tanks, a description of which has previously been pub1ished.I Each tank is slightly over four feet square and four feet deep with a capacity for about three and one-half tons of soil. They receive the natural rainfall b u t no other supply of moisture. Twelve tanks were filled with clay loam soil of uniform character in 1909 and crops were raised on certain of the tanks in 1910. The drainage water was measTABLE

I.-FLow

OF

DRAINAGE WATER

(IN

LITERS)FROM

THE

and also the drainage between October I , 1910,and May 1, 1911. I t is probable that the composition of the drainage water does not a t present correspond exactly t o that of the soil in the field. Monthly analyses of drainage from two of the plats show a gradual reduction in the concentration of the solution. The soil was well compacted when placed in the tanks, each horizontal foot being packed in the tanks in the relative position which i t occupied in the field. As there has been almost no settling of the soil since these receptacles were filled, it is probable t h a t no abnormal aeration is now taking place. The effect of plant growth during the summer of 1910on the density and composition of the drainage water collected between Oct. I , 1910.and May I, 1911,is very apparent, when the flow from the unplanted tanks is compared with that from the tanks on which plants were raised. Owing t o the fact t h a t . of the drainage collected between May 23 and Oct. I , a very small proportion was collected after the plants. began to grow vigorously, this liquid does not show so markedly the effect of plant growth on the soluble matter of the soils. Three tanks contained no plants, four were planted to maize and two to oats. A statement o'f the average flow of drainage water by months from tanks unplanted, planted t o maize and planted to oats is given in Table I . Both the maize and oat tanks were planted on May 2 3 , the date on which the measurement of the flow of drainage began. Oats ripened about Aug. 7th and maize continued t o grow until the latter part of September. The growth of the crops did not curtail the flow of drainage until July and even then the dry weather reduced the flow from the unplanted tanks practically as much as from the planted. The removal of water from the soil by the plant did not influence the flow of drainage until September and fram then until

AVERAGE TANKW H E N

PLANTED TO MAIZE AND

U N P L A N T E D ; WHEN

May 23 Tank S o s .

Crop.

2,4,8

None Maize Oats

3, 5, 7 . 9 6 , 10

to June 1 . 48.8 44.6 50.1 'L'ABLE

Tank Nos

Crop

2, 4. 8 3, 5, 7 , 9 6 , 10

None Maize oats

June. July 25.9 24.3 24.0

1 1 0.8 0.2

Sitrntes

606 389 430

T3.7 31 9 45 6

(SO:+l.

Total

Ni trntes

Crop.

solids

(SO31

2. 4 . 8 3, 5 . 7 . 9 6 , 10

h-one Maize

618 264 2i 1

136 . O 14.6 14.6

hug. Sept.

Oct.

No".

Dec.

Jan.

Feb.

Mar.

0.1 0.0 0.2

31.0 0.1 0.0

90.3 0.0 6.0

73.1 4.8 52.7

199.6 176.9 149 3

14.0 9.0 6.0

156.0 172.6 172.3

45.2 0.6 0 0

Bicarbonates (HCO:jl

Silica (SiO?)

372 286 255

8.9

OF

I

,

D R A I N A G\\'ATER, E

Bicarbonates (HCOal 256.0

in1

- _

9 6

.o

192 0

Silica (Sios) 6 .4 4.8 4 6

ured each month. An aliquot portion of the drainage water mas removed from the receptacles from time t o time for analysis. Samples representing the flow betm*een May 2 3 and October I , 1910, were analyzed Science, .V, S I 29, 621-3

PLANTED TO OATS

May 2 3 , 1910, to Apr. May 1 . 1911. 76.6

84.5 105 4

761,7 518.2 566.2

Total from Oct. 1 . 1910, tv May 1 . 1911. 640 6 447.9 491.7

11 - ~ O > l P O S I T I ~ X O F D R A I N A G E W A T E R , P A R T S P E R M I L L I O X . M A Y 23 TO OCT. 1, 1910

'1'otal solids.

'l'ank Sos.

1

WHEN

Total from

T A B L EIlI.--CoiIrosI'rms

Oats

Oct., 1911

Phosphates (PO&i. trace trace trace I'ARTS

Calcium

(ME).

Pi . 9

15.9 in .o

71.7 x0 9

PER ~ i l L L l U S ,O C T

Phosphates (PO,). trace trace trace

Magnesiuni

(Ca)

19 1

Potassium (K) 2.2 1.1 1 2

Sodium (Na) 29.9 15.3 14 2

1 . 1910, TO M A Y 1. 1911.

Calcium

Magnesium

Potassium

Sodium

(Ca)

(hfg).

(K).

(h-a).

96 8 5 2 .9 52 I

18 7 8 .4 8 8

2.6 2 2 4 0

25.8 21 1 l i .4

January the unplanted tanks gave a much greater flow, The composition of the drainage water in parts per million is stated in Tables I1 and 111. The unplanted tanks show quite a constant density of

Oct.,

T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y .

1911

total solids for both the summer a n d winter months. In t h e drainage from the unplanted tanks the bases ( C a , Mg, K , Na) have about the same density in both t h e summer and winter, as does also the silica. The chief difference is in the nitrates and bicarbonates, the former being much richer in winter while the latter occur in less density a t t h a t time. Determinations of nitrates in similar soils indicate very plainly t h a t the nitrate formation occurs largely during midsummer in spite OF the Fact t h a t they appear most abundantly in the winter drainage. As may be seen from Table I the flow of drainage water previous to Oct. I is largely spring flow and does not represent the result of the reactions t h a t occurred in the soil during the important part of the growing season. It is quite evident t h a t t h e drainage collected betwwn Oct. I , r g r o , and May I , 1911. Lvillserve better as thc basis for a study of the influence of vegetation on the removal of mineral matter in the drainage water. In Tables IV and Y, the substances removed in the drainage water have been calculated to pounds per acre. I t will be noticed t h a t the large differences are between the planted and the unplanted tanks. study of the winter drainage shows: IS PER . % C R E . M A Y

Phosphates (PO,) trace trace trace

Calcium (Ca). 66.3 27.6 31.8

Bicarbonates (HCO.Il

Silica (Si02) .

C alci urn (Ca)

890 i 446.9 517 0

22 6 11 8 12 1

340 4 130.4 141 .6

The total solids removed from the unplanted soils was three times as great as t h a t removed from the planted soil. The loss of nitrogen in drainage water was more t h a n twelve times as large from the uncropped soils as from those t h a t grew plants. Slightly over one hundred pounds of nitrogen per acre were lost from the uncropped soils during the period mentioned, while only eight pounds were lost from the cropped soils. The use of a catch crop would be of slight benefit during the fall, winter and early spring on this soil when a good summer crop is raised. Very little more nitrogen was lost from t h e soil on which oats mere raised t h a n from the soil on which maize was grown, although the nitrogen in the crop was nearly fifty pounds per acre less on the oat soil. The nitrogen in the maize crop plus t h a t in the drainage water from the tanks cropped t o maize amounted t o 151 pounds per acre. T h a t in the oat crop and drainage from the oat t a n k s amounted to 103 pounds per acre. There were, therefore, 48 pounds per acre more available nitrogen in t h e maize soil than in t h e oat soil. This is i n line with the results of previous work by the writers which indicated either t h a t the

743

23, T O O C T . I . 1910

(Mgi.

I'otnssium (K)

Sodium (iT3I .

10.8 6.8 7.8

I .4 0A 0 .4

19.5 6.2 5.8

Xlagnesium (Mg) 65.2 23 4 23 9

Potassium (K

Sodium (Nal

9.6 5.3 9 2

92.1 53 . o

Xagnesium

16,1

ninety pounds per acre. However, the ratio between the loss from the cropped and uncropped tanks was not so great as was the ratio for calcium. The bicarbonates were large in amount, b u t the much greater loss of basic material from the uncropped than from the cropped soil was removed mainly in the form of nitrate and not as bicarbonate Any system of soil management which results in a decreased removal of nitrates in the drainage water will probably effect a conservation of bases in t h e soil. The tendency of new soils in a humid region t o become "sour" after being cultivated for a number of years may be explained b y the abundant formation of nitrates in such soils when first tilled, and the consequent removal of corresponding quantities of calcium in t h e drainage water, Forest soils, in which nitrification is said t o be absent, and permanent grass land, in which nitrification is hardly more t h a n sufficient t o supply the crop, doubtless lose very little calcium as compared with the same soils under the plow. CORSELL USIVERSITY. ITHACA,S . Y . 1 .I F v i i u k . Iurl , J a n . a n d I'eb

,

1911, pp. 1-16, 205-28