Ecosystem Interactions Class Discussion Presentation in Blue Green Lined Styl...
Operational Manual for Production of Vermicompost
1. OPERATIONAL MANUAL
FOR
(Production of VERMICOMPOST)
(RURAL AGRICULTURAL WORK EXPERIENCE PROGRAMME)
Dr. S.R. Sharma
(Professor)
2013-14
DEPARTMENT OF SOIL SCIENCE AND AGRICULTURAL CHEMISTRY
S.K.N. COLLEGE OF AGRICULTURE
(S.K. N. AGRICULTURAL UNIVERSITY, JOBNER)
JOBNER-303 329
2. 2
Exer.
No.
Particulars Page
No.
Signature
1. Identification of earthworms
2. Collection and preparation of bedding materials
3. Preparation of beds for vermicompost and inoculation of
vermiculture
4. Separation of vermiculture and vermicompost
5. Maintenance of vermiculture
6. Preservation and packing of vermicompost
7. Determination of quality standards of vermicompost:
Analysis for N, P and K
8. Estimation of organic carbon in vermicompost
9. Fractionation of vermicompost
10. Drawing of flow-sheet chart of vermitechnology
INDEX
3. 3
INTRODUCTION
Vermicomposting is an ecofriendly, low cost effective and a effective way
to recycle agricultural and kitchen waste. The application of vermicompost not
only adds plant nutrients (macro and micro) and growth regulators but also
increases soil water retention, microbial population, nutrient content and carbon
content of the soil.
Vermicompost refers to an organic manure produced by earthworms. It is
mixture of worm castings, organic material including humus, live earth worms
and their cocoons and other organisms. Vermicomposting is a appropriate
technique for the disposal of non-toxic solid and liquid organic wastes. It helps in
cost effective and efficient recycling of animal wastes agricultural residual and
industrial wastes using low energy.
The key role of earthworms in improving soil fertility is well known.
Earthworms feed on any organic waste, consume two to five times their body
weight and after using 5-10 per cent of the feed stock for their growth, excrete
the mucus coated undigested matter as wormcasts worm cast consists of organic
matter that has undergone physical and chemical breakdown through the activity
of the muscular gizzard which grinds the material to a particle size of 1-2 micron.
The nutrients presents in wormicast are readily soluble in water for the uptake of
plants. Worm casts are rich source of macro and micro nutrients, vitamins,
enzymes, antibiotics, growth harmones and immobilized microfloras.
In Rajasthan gross cultivated area is 20.69 m ha and out of which 33.3 %
area falls under irrigation. The recommended dose of FYM per hectare is 5-10
ha-1
. Therefore, the total requirement of FYM may be estimated as 34 to 68 m t
per year. The availability of FYM is about 4.7 m t per year. Thus 29.3 to 63.4 m t
of FYM per year is still lacking. The total organic waste material is produced 875-
1300 mt per year and this material can be processed either by vermicompositing
or by other composting methods and the demand of 29.3 to 63.4 mt of FYM per
year can be full filled and the whole process of vermicomposting can ensure
supply of organic matter to the fields and can provide job to the persons.
4. 4
Increased usage of chemical with out adequate organic recycling has not
only aggravated multinutrient deficiencies in soil plant system but also
deteriorated soil health and created environmental pollution.
The world market for organic food production is estimated to be worth
around 35 billion annually. The annual growth rates of worldwide sales are
between 10-30%. It is estimated that the market could be worth between $100
and $190 billion by 2006. More than 130 countries, currently produces
commercial quantities of certified organic food and agricultural products. Strong
consumer demands, high premiums and government subsidies to convent
organic production methods are driving further growth in the organic production.
In developing countries, where existing agricultural production techniques are
depend on lower inputs and are close to being organic, could provide source of
the organic production and the growth is needed to satisfy demand.
Vermicompost
What It is a cast of earthworms.
Why It is required to full fill the following objectives.
Vermi
composting
Agricultural waste
Demand
of
FYM
Soil & Plant pollution
Sell Job
&
to thers
Organic
recycling
Save chemical
fertilizers
Adds in
national
economy
Sustained soil
production &
fertility
5. 5
Exercise No. 1 : Identification of earthworms
Classification, identification of earth worm
Phylum - Annelida
Class - Oligochacta
Order - Opisthopora
Genus - Pheretima
Species - Eisenia foetida
- Lumbricus rubellus
Characteristics
Procurement of earthworm and required material: - Spade, tap, pillars,
cencherus munja to made the shade / cloth for cover, sutli, plant residues,
organic waste, cow / buffalo dung, gunny bag or banana leaves, necessary
arrangement for water supply, worm culture (cocoon) etc.
Types of earth worms
India has about 3000 species of earth worms, which are adapted to a
range of environment and vermiculture needs. Earthworms can be divided into
the following two broad groups:-
(i) Epigeic- The suface living worms
(ii) Epiarecic- The burrowing worms
Epigeic or manure worms are found on the surface and are reddish brown
in color. They do not process the soil but are efficient in composting of organic
wastes. They enhance the rate of organic manure production. Through
biodegradation or mineralization and nutrient mobilization. The local species are:-
Lampito mauritii
Octochaetona serrata
Perionyx excavatus
6. 6
Epianecic species burrow and mix the soil from different horizons in the
profile. They ingest organic and mineral fractions of soil. Thus promoting the
formation of organic complexes. Organic mineral crumbs are brought from
deeper parts of the soil profile to the surface.
In temperate regions, humus feeders (epianecic) dominate over the
organic matter feeding (epigeic) worms in tropical coantries. Epianecic worms
can not feed directly on partially degraded organic matter. In the tropics, a small
group of 4-10 cm long worms having dark pigmentation are found in the litter
heap, dung pad or near the cattle shed during monsoon.
The worms do not enter the soil strata.
Earthworms species for vermicompost
Name place of residence
1. Lampito mauriti Sandy loam soil
2. Octochaetona serrata Clayey soil
3. Lumbricus terrestris Deep boarings
4. Allolobophora caliginosa shallow boarings
5. Eudrilus eugeniae
6. Eisenia foetida
7. Perionyx excavatus
8. Pheretima elongate
The Eisenia foetida an epigeic species of earthworms is used for
vermicomposting. The general characteristics of Eisenia foetida are as under :
Habit : Epigeic
Size : 8-10 cm
Diameter : 0.8-1.0 mm
Duration of life : 70 days
Temperature range : 15-40 0
C
Approximate weight of : 1.0-3.0 g
single earthworm
Mopisture tolerance range : 30-70%
Habit and Habitats : Living on surface and organic
matter rich areas
7. 7
Exercise No. 2 : Collection and preparation of bedding materials
Bedding material :
1. Agriculture waste
2. All type of weeds
3. Litter falls of trees
4. Kitchen waste
5. Agricultural industrial waste
6. All spoiled food grain and food materials
7. Wastes of dinner or get together
8. Wastes of animal feeding
All the materials which are treated as waste, only burned and that can not
be utilized by human beings and animals are useful for preparation of bedding
material for earthworms.
(i) Initial digestion:
Dig a pit of the size 6 x 6 x 3 or prepare a chamber on the ground surface
of the size 6’ x 6’x 3’ or depending open number of cows /buffaloes etc or
availability of cowdung and agricultural waste and put cowdung on the ground
surface of pit by farming Ist larger and than put agricultural waste as a second
layer the ratio of 8:5 repeat the preparation of these alternate layers of cowdung
and agricultural waster till the chamber is not filled. The last layer or top layer of
the chamber should be cowdung. The cowdung and agricultural wastes filed in
the chamber should be appreciatively in the 8:5 ratio. Than saturate the chamber
with water and than keep it for 10 days.
Results
1. The materials which are collected:
2. Temperature and moisture of the bedding material is :
8. 8
Exercise No. 3: Preparation of beds for vermicompost and
inoculation of vermiculture
Preparation of vermicomposting bed:- Select a place in vermicomposting shed
and mark an area of 3 x 10 feet and spread on it hard woody agricultural waste to
form a basement layer and spray water till it is wetted well and than collected the
material from initial digestion chamber and put it on the bed, prepared in the size
3 x 10 feet up to the height of 1½ -2 feed and check the moisture and after
confirmation of the proper moisture, inoculate the bed by the earthworms culture
which is required @ 3 kg vermiculture per bed of the size 3x10 feed. Cover the
bed with green leaves/ weeds/ banana leaves/ gunny begs etc. After every 3-5
days of interval in summer or 7-10 days of interval in winters, watering should be
done by spraying on the beds till vermicomposting process completed. The
spraying of water should be of the pH 7.0 to 7.5 or upto 8.0. The
vermicomposting process in the bed will take only 35-40 days, stop watering after
35-40 days and remove the cover and separate the vermicompost and
vermiculture.
RESULT:
1. The vermicompost prepared in :…………….. day
2. The test of completion of vermicompost are: A.
B.
3. The moisture content and temperature at final stage of vermicomposting
A. Moisture content ………………………. %
B. Temperature ………………………. 0
C
PRECAUTIONS:
(i) Always maintain 30% moisture in each layer during whole of
process of vermicomposting and watering should be done at 15
9. 9
to 20 day of interval in winter and 7 to 10 days in summer or as
per requirement to maintain 30% moisture.
(ii) Maintain the population of earthworms by 150/5 Sq M in IIIrd
layer.
(iii) During summer special care should be taken to maintain
optimum moisture for that add 3-4 time of water.
(iv) Avoid heavy watering during the process of composting.
(v) Protect earthworm from enemies i.e. birds and ants.
(vi) Use fresh dung during the preparation of lined layer because
fresh dung is most desired substrate of worm.
(vii) Charging and checking of earthworms once in 8-9 weeks to
ensure their regular multiplication.
(viii) The over all thickness of all layers must be up to 1½ feet.
(ix) Worms hatch out with in a month. They start processing the
organic much and produce vermi casting.
10. 10
Exercise No. 4 : Separation of vermiculture and vermicompost
Separation of the vermicompost and vermiculture : Loose the bed with the
help of iron Panja/ Kushi/Dantali and wait for 5-10 minutes or till earthworms
reaches to lower layers. Than with the help of wooden stick, remove a layer free
from earthworms and their eggs. Repeat this process of separation for three time
and collect the removed material (vermicompost) and sieve it and keeping for the
further use. The material remained in the bed will be vermiculture, collect it and
keep it for its survival in vermiculture bed.
Results:
1. The earthworms separated from vermicompost
2. The vermicompost separated and sieved and collected in heap and
maintained moisture
11. 11
Exercise No. 5 : Maintenance of vermiculture
Prepare a bed containing cowdung and agriculture waste containing
sufficient moisture and the culture received from vermicomposting beds is stored
in this beds and moisture is maintained till its further use. The culture also
protected from enemies.
Results
12. 12
Exercise No. 6 : Preservation and packing of vermicompost
1. Preservation:
The vermicompost collected from beds is sieved by four mesh sieve and
collected in a heap and moisture is maintained till it is utilized for production of
crops, nurseries, trees etc.
2. Packing of vermicompost
After application of sufficient moisture, the material is weighted and filled
into the plastic bags and sealed. The packing bags are of 2, 5, 10 and 50 kg
capacity are generally used.
Results
13. 13
Exercise No.7: Determination of quality standards of
vermicompost: Analysis for N, P and K
Quality Standards of Vermicompost
Average nutrient content of vermicompost
S. No. Nutrient Vermicompost FYM
1. N% 1.6 0.75
2. P2O5 % 2.04 0.17
3. K2O 0.80 0.55
4. Ca % 0.44 0.91
5. Mg % 0.15 0.19
6. Fe (ppm) 175.2 146.5
7. Mn (ppm) 96.51 69.0
8. Zn (ppm) 24.43 14.5
9. Cu (ppm) 4.89 2.8
10. C : N 15 : 5 31 : 28
Source : Purakayastha and Bhatnagar (1997)
Comparative nutrient content of composts
S.
No.
Compost Nutrient content % of
drymatter
N P2O5 K2O
1. Vermicompost 1.6 2.2 0.67
2. Rural compost 1.22 1.08 1.47
3. Urban compost 1.24 1.92 1.07
4. Paddy straw compost 0.90 2.05 0.90
5. Maize stalk compost 1.09 1.30 1.01
6. Cotton waste e.g. nut full compost 1.62 1.04 1.26
Source : Venkatranum (1997)
14. 14
Vermicompost can also be called as biological manure and it contains not
only mainly micronutrients like Mn, Fe, Mo, B, Zn, Cu but also contains some
growth regulators and a good amount of microbial population (Singh and Rai,
1997).
Population of cocoon population of earthworms in culture should be 150
cocoon / 5 Sq.m.
Temperature for activity the most conductive temperature for the activity of
worms ranges between 26-35°C.
15. 15
7.1 Determination of total N in vermicompost
Principle:
The material is digested with H2SO4 and salicylic aid in the presence of
K2SO4ˉ, FeSO4, CuSO4 and sodium thiosulphate (NaS2O3). In this process
K2SO4 acid raises the boiling point of H2SO4 and CuSO4 as a catalyst. Salicylic
acid forms Nitrocompounds (nitrogen salicyclic acid) which are reduced by
Na2S2O3 to amino (ammonia) compound. This ammonia is then estimated by
kjeldahl method as described in estimation of N including NO3 in plant material.
In the above method zinc dust can also be used in place of sodium thiosulphate
to reduce nitrosalicylic acid to aminosalicylic acid. The various reactions are as :
C6H4OH.COOH + HNO3 …….. C6H3OH.NO2COOH + H2O
Salicylic acid Nitrogen salicylic acid
The nitrosalicyclic acid is reduced to amino-salicylic acid by the action of
sulphurous acid formed by the reaction between sulphuric acid and sodium
thiosulphate.
Na2
S2
O3
+ H2SO4 …………… Na2SO4 + S + H2SO3
Sulphurous acid
C6H3OH.NO2COOH+3H2SO3+ H2O …. C6H3OH.NH2COOH + 3H2SO4
Amino salicylic acid
2C6H3OH.NH2.COOH+27H2SO4 …. (NH4)2 SO4 + 26SO2 +14CO2 + 30H2O
Reagents and apparatus:
16. 16
(i) Kjeldahl digestion and distillation assembly
(ii) Concentrated H2SO4.
(iii) Standard HCI solution: N/10
(iv) NaOH solution (45%): Prepared by dissolving 450 g NaOH in one litre
of distilled water.
(v) Mixed indicator: Dissolve 0.5 g bromocresol green and 0.1 g methyl
red in 100 ml of 95 per cent ethanol.
(vi) Boric acid 4% (indicator solution) : Dissolve 40 g H3BO3 in 1 litre
distilled water by heating gently. Add 5 ml of mixed indicator in it and
adjust pH of boric acid to 4.5 by using NaOH or HCI (colour turns from
blue to slightly pink).
(vii) Granulated zinc: To prevent bumping in distillation flask.
(viii) Mixture: Prepare by mixing 10 parts anhydrous sodium sulphate or
potassium sulphate + 0.3 parts copper sulphate. anyhydrous Na2SO4
or K2SO4, raise the boiling temperature of digestion mixture whereas
CuSO4 acts as catalyst and hasten the digestion. Other catalyst which
can be used are HgO, Hg, Se powder etc.
(ix) Sulphuric acid + Salicylic acid mixture: Add one gram of salicylic acid
to 30 ml of sulphuric acid.
(x) Sodium thiosulphate, finally ground crystals or zinc dust.
Method:
(i) Take one gram of sample and transfer it into a kjeldhal flask.
(ii) Add about 30 ml of sulphuric acid salicylic acid mixture.
(iii) Shake until thoroughly mixed and keep the flask for about half an hour
for the reaction to proceed.
(iv) Add 5 g of sodium thiosulphate (or 2 g zinc dust) and heat over a low
flame till frothing ceases. Then raise the heat and continue boiling until
white fumes cease to come out.
17. 17
(v) Raise the heat to boil the contents until solution is clear and then
continue digestion for at last 30 minutes. (Solution become whitish
upon complete digestion)
(vi) Cool and add slowly with intermittent shaking about 200 ml of water
and cool again.
(vii) Add few pieces of granulated zinc in the flask to prevent bumping, tilt
the flask and about 80 ml of 45 per cent NaOH gently so that the
contents do not mix.
(viii) Immediately connect this flask to distillation assembly and see that the
end of condenser tube dips into the 50 or 100 ml 4 percent boric acid
solution contained in the receiving 250 or 500 ml conical flask along
with mixed indicator. Mix the content of the flask by swirling.
(ix) Distill ammonia at moderately high heat for about 45 minutes till at
least 150 ml of distillate has been collected. Test with red litmus paper
if any NH3 is still coming out.
(x) Remove receiving flask with putting off the heating and rinse out-let
tube into receiving flask with a small amount of distilled water.
(xi) Titrate the content of receiving flask with standard 0.1 N HCl till blue
color disappears. Simultaneously run blank using all reagents in the
same quantity but without the sample.
Observation and calculation:
i. Blank reading =
ii. Sample reading =
When 10 ml of 1 percent fertilizer solution is taken
Where T = (Sample reading – Blank reading)
Per cent N in fertilizer =
0.0014 x T x 100 x 100
10
18. 18
In case on gram sample is taken directly, dilute the digest to 500 ml and
take 25 ml of it for distillation and calculate percent N as follows:
Note:
(i) If the flame or electricity goes out off during distillation, immediately
remove the receiver flask containing standard acid to prevent the
contents from being sucked back into the kjeldahl flask Light the burner
(or start the heater) and then replace the receiving flask. If there is
severe bumping, regulate the flame or heater gradually till it is low.
Continue distillation for about 45 minutes. At the end, without putting of
the burner or heater, disconnect the dipped tube from the condenser.
Rinse it with distilled water.
(ii) The granulated zinc is added to prevent bumping during distillation.
Zinc reacts with dilute sulphurinc acid producing minute bubbles of
hydrogen, which help in preventing bumping. The sulphuric acid used
may contain traces of ammonium sulphate and the distilled water
exposed to the laboratory air may contain traces of ammonium
hydroxide. Hence it become necessary to carry out a blank
determination by which any extraneous nitrogen is determined and
subtracted from the total value.
Per cent N in V. =
0.0014 x T x 500
25
X 100
19. 19
7.2 Determination of total phosphorus in vermicompost (Volumetric
ammonium molybdate method)
Principle:
Phosphorus is precipitated from the acidic solution as ammonium
phosphomolybdate (NH4)3 PO4ˉ - 12 MoO3 ) by adding ammonium molybdate
solution. The precipitate is dissolved in measured excess of the standard alkali;
after filtration and washing till free from the acid. The equations involved are as
follows:
I. Precipitation:
Na3PO4+12(NH4)2MoO4+24HNO3 …
(NH4)3PO4ˉ12MoO4+3NaNO3+21NH4NO3+12H2O.
II. Dissolution of precipitate in standard alkali:
(NH4)3PO4. 12MoO4+23NaOH ...
11Na2MoO4+NaNH4HPO4+(NH4)2MoO4+11 H2O
Reagents:
(i) Ammonium molybdate solution 3 per cent: 3 g of ammonium molybdate is
dissolved in hot distilled water and makes its volume to 1 litre.
(ii) Standard NaOH solution: 0.1 N.
(iii) Standard H2SO4 solution: 0.1 N.
(iv) Sodium nitrate 2 per cent: 20 g sodium nitrate A.R. grade is dissolved in 1
litre of distilled water.
(v) Phenolphthalein indicator: 1 g phenolphthalein is dissolved in 100 ml of
95.5% ethanol.
(vi) Magnesium nitrate solution (9%). Dissolve 90 gram of phosphorus free Mg
(NO3)2 in water and dilute to 1 litre.
20. 20
Method:
Preparation of sample solution: According to the nature of fertilizer, the
sample solution should be prepared with one of the following methods.
(i) For materials and fertilizer mixtures containing high organic material: Take
1 g sample in evaporation dish. Add 5 ml of Mg (NO3)2 solution and
evaporate to dryness. Then ignite to destroy organic matter and dissolve
in 10 ml HCL.
(ii) For materials containing small quantity of organic matter: Take 1 g sample
in a 50 ml beaker. Add 30 ml HNO3 and 5 ml HCI and boil gently until the
organic matter is destroyed and red brown fumes cease to appear.
(iii) For fertilizers containing much Fe or Al phosphate and basic slag: Treat 1
gm sample with 30 ml HCI and 10 ml HO3 and boil gently until red brown
fumes disappear.
Cool the solution prepared by any of the three above methods, dilute to
250 ml mix and filter through dry filter if required.
(i) Pipette out 5 to 25 ml aliquot depending upon the P content (containing
not more than 25 mg P2O5) in a 250 ml beaker. Dilute it with 100 ml
distilled water.
(ii) Add approximately 5-10 ml of concentration HNO3 and about 10 g
ammonium nitrate.
(iii) Heat this mixture on a water bath at 55-60 OC till it is just unbearable
to hand.
(iv) Ad 3 per cent ammonium molybdate solution in beaker drop by drop
with the help of burette. Continue stirring with a glass rod till about 5 ml
of molybdate solution have been added. Stir for another few minutes till
the yellow precipitate appears to become granular.
21. 21
(v) Cover the beaker with glass and allow it settle for some time. Draw the
clear solution through a what man no.44 filter paper and wash the
precipitate with 2 percent sodium nitrate solution agitating thoroughly
and allowing the precipitate to settle. Transfer the precipitate on to the
filter paper and wash with NaNO3 solution till free from acid.
(vi) The precipitate and filter paper are then transferred to the beaker and
two ml of 0.1 N NaOH is added at a time by pipette till the precipitate
become soluble.
(vii) Add 1-2 drops of 1 per cent phenolphthalein and titrate the excess of
alkali against 0.1 N sulphuric acids.
Observations and calculation
As per equation II
23 x 40 g NaOH = 31 g P = 71 g P2O5 or 23 g equivalent of NaOH = 31 g P = 71
g P2O5.
Since a normal solution contains 1 g equivalent per litre
Thus 0.003088 is the factor for P2O5 corresponding to 1 ml of 1 N alkali
Volume of the aliquot (solution) taken = 5 ml
Total volume of fertilizer solution = 250 ml
Suppose volume of 0.1 N NaOH required to dissolve the precipitate = 40 ml (V1).
Volume of 0.1 N H2SO4 used for titration to neutralize excess alkali = 10 ml (V2)
31
23I equivalent of NaOH =
g P = 71
23
g P2O5
1000 ml of 1 N NaOH =
71
23
1 ml of 1 N NaOH =
71
23
1
1000
g P2O5 = 0.003088 P2O5X
22. 22
Then volume of 0.1 N NaOH used for precipitate = 40-10 = 30 ml
Where,
N1 = Normality of the standard alkali
N2 = Normality of standard acid,
F = Factor for P2O5.
Per cent P2O5 =
F x (V1N1 – V2N2) x Vol of total fert. Solu.
Aliquot taken
100
Wt.of Fert.
x
=0.003088 x (40 x 0.1 – 10 x 0.1) 250
5
100
1
= 46.32x
23. 23
7.3 Determination of potassium in vermicompost by cobalty nitrite method
Principle
Sodium cobaltinitrite {Na3 CO (NO2)6}, when added to a solution of
potassium salt, forms a canary yellow precipitate of potassium sodium
cobaltinitrite K2Na {CO (NO2)6} H2O. The precipitate is dissolved in a known
volume of standard KmnO4 solution, the excess of which is determined by back
titration with standard oxalic acid solution.
10K2Na {CO (NO2)6} H2O + 22 KmnO4 + 58 H2SO4
= 21K2SO4 + 5Na2SO4 + 10COSO4 + 22 MnSO4 + 60HNO3 + 38 H2O
Reagents and apparatus
(i) Sodium nitrate: 175 g NaNO3 free from K+ and NH4+ ions is dissolved
in distilled water and make the volume to 500 ml.
(ii) Cobalt nitrite: 100 g cobalt nitrite free from K+ and NH4+ ions is
dissolved in distilled water and dilute to 500 ml.
(iii) Saturated sodium chloride: 350 g NaCl is dissolved in 1 litre distilled
water. Filter and cool. (Solution may be warmed during dissolution).
(iv) Alcohol (35 per cent) : 420 ml of alcohol is diluted with 600 ml distilled
water.
(v) N/20 standard KmnO4 solution.
(vi) N/20 standard oxalic acid solution.
Sample preparation
Weigh accurately 5 g of the sample in an evaporating dish and incinerate
in muffle furnace to carbon-free ash. Heat the ash with 10 ml of concentrated HCl
for 10 minutes, Cool and transfer into a beaker. Wash the dish with distilled water
several times and collect the washings in the beaker. Dilute with water to about
150 ml and heat to boiling. Add powdered barium hydroxide to make the contents
24. 24
just alkaline. Cool, make volume up to 250 ml and evaporate to dryness in a
porcelain dish. Heat the reside gently over a low flame with a few ml of
concentrated HNO3 till all ammonium salts are expelled. Wet the residue with
concentrated HCI and again evaporate to dryness. Add dilute HCI and digest on
a water bath. Filter and wash free from chloride. Use the filtrate for precipitation
of potassium.
In the presence of NH3, Ca and Al etc. (for determination of K in NPK
complexes and NPK fertilizer mixtures:
Place 2.0 gram of sample in 250 ml volumetric flask. Add 125 ml water
and 50 ml of 4 per cent ammonium oxalate (NH4)2 C2O4) solution,. Add 1 ml
diglycon streate, to prevent foaming, if needed. Boil for 30 minutes, add light
excess of NH4 OH and after cooling dilute to 250 ml, mix and pass through dry
filter No.12 or equivalent.
Method
(i) Prepare 0.25 per cent solution of fertilizers by procedure given in a or b
or c after adjusting amount of fertilizer taken and corresponding
dilution. Take 10 ml of 0.25 per cent fertilizer solution in a Pyrex beaker
or glazed dish.
(ii) Dry the fertilizer solution on a water bath and after cooling add 1.5 ml
of glacial acetic acid and 10 ml of saturated sodium chloride solution.
(iii) After 4 minutes add 4 ml of 35 per cent NaNO3 solution and stir again.
(iv) After 5-10 minutes (not more than that) when reaction is complete, add
5 ml of 20 per cent cobalt nitrite solution rapidly with constant stirring.
(It should not take more than 3-4 seconds).
(v) Stir 40-60 seconds. Cover and allow it to settle overnight in a cool
place free from fumes of ammonia.
25. 25
(vi) Filter through a gooch crucible charged with asbestos or use sintered
glass crucible number 4.
(vii) Transfer to precipitate to the crucible and wash 4 times with 6-10 ml of
35 per cent alcohol each time. Finally wash the crucible with 3 small
lots of 2 ml each of cold water to remove alcohol.
(viii) Pipette out 50 ml of N/20 KmnO4 in a 400 ml beaker. Dilute it to about
150 ml with distilled water and add 5 ml of H2SO4.
(ix) Add the crucible along with precipitate in this mixture and keep it
submerged in the solution and warm gently. If the color appears to be
discharged add further known quantity of KmnO4 solution to ensure
excess.
(x) Now heat nearly to boiling. Remove from the heat (flame) and after few
minutes add excess of N/20 oxalic acid nearly 50 ml.
(xi) Warm until all oxides of Mn have been dissolved.
(xii) Titrrate excess of oxalic acid with N/20 KmnO4. The difference
represents the amount of KmnO4 used for oxidation of the precipitate.
Observations and calculations
Amount of fertilizer solution taken = 10 ml
Amount of N/20 KmnO4 solution added = 50 ml
Amount of N/20 oxalic acid solution added = 50 ml
Volume of N/20 KmnO4 solution required for the excess of oxalic acid= xml
Volume of N/20 KmnO4 used for reacting the precipitate = (50-x) ml
% of K2O = Ml of N/20 KmnO4 x Total volume of fertilizer solution
Volume of solution taken
100
Wt. Of
fertilizers
x
26. 26
Exercise No. 8 : Estimation of organic carbon in vermicompost
Determination of organic matter b1 ash ba method
Method: Weight 10 g of the well-mixed manure vermicompost in a dry nickel
crucible of silica basin. Heat it on a low flame, till the organic matter begins to
burn. Place the crucible in a muffle furnace at dull red heat i.e. at about 550C
when grayish white ash is formed; remove the crucible from the furnace. Cool in
a desiccator and weigh. The residue represents the ash. The loss in weight arid
represent the moisture and organic matter.
Observation and calculation:
Wet of the crucible = c
Wet of the crucible + manure = b
Wet of crucible + manure after ignition = a
Ash, g/100 g = (a-c)
------------ x 100
b-c
Percentage of ash on original basis =
Percentage of organic matter = 100-Z-M
Organic matter % = 100-% Ash
%organic carbon = % organic matter
1.724
Note: Percentage of organic matter and ash is usually calculated on oven dry
basis.
Results
The organic carbon content in giving sample of organic manure is
…………………
27. 27
Exercise No. 9 : Fractionation of vermicompost
Organic matter
Acidity to pH 1.5 Water + domination
Acidity to Ph 1.5
Soil
NaOH
extractable
Humin
Humicaue
Precipitate
A
Fulivic acid
soluble
A
Sonipied water
expact
Humic acid
B
Falvic acid
B
28. 28
The waste-retention basin sampled for this study was constructed in 1993
and is located in north central Iowa. The basin is permitted for 1.8 million
gallongs, with about 1.3 million gallongs being pumped out in the spring and fall
of each year. No fresh water is added to this basin as it fills with swine waste.
This basin received waste from five buildings that housed about 5700 swine at
the time of sampling. The average weight per animal was about 135 pounds at
this time. In an effort to reduce the adors from this basin, the operator has added
paper cuttings in previous years and soybean stover in the current year (2003).
Sample collection
Two unfiltered 1-liter samples were collected in amber glass bottles in
July, 2003. One sample was collected close to the waste in-flow pipe (north-side-
sample), and one was collected on the other side of the basin opposite the waste
in-flow pipe (south-side sample). The samples were chilled on ice and shipped
overnight to the U.S. Geological Survey National Water Quality Laboratory, and
immediately analysed with minimal refrigerated storage to minimize sample
degradation.
Organic Matter Fractionation
The north side sample was fractionated in a comprehensive scheme,
presented in figure 1, designed to obtain compound class information for
particulate, colloidal, and dissolved organic matter. This is the first
comprehensive fractionation scheme designed to include volatile acid and
particulate organic matter with the published scheme (Leenheer and others,
20000 for fractionation and analyses of colloidal and non-volatile dissolved
organic matter. The south side sample was used to evaluate a non-
comprehensive solvent extraction scheme (Fig. 20 for comparison of a typical
solvent extraction analyses with the comprehensive analytical approach. This
comparison assumes there were no significant differences between the north and
south side samples as the ph and conductivity values (measured in the
laboratory) were identical for these two samples.