145
12 Household Detergents Causing Eutrophication in Freshwater Ecosystems
4. Nitrates
Nitrates were calculated from the standard pattern. Standard
pattern was prepared between concentration of nitrates and
absorbance from 0.0 to 1.0 mg/L of nitrates at the NO 3 -N at
the interval of 0.1 by finding the absorbance of standards.
5. Phosphates
The concentration of phosphate calculated with help of standard pattern. The standard pattern was prepared in the range
of 0.0 to1.0 mg/L of PO 4 -P at the interval of 0.1, following
the same method described for the NO 4 -N.
6. Potassium
The estimation of potassium was carried out directly with the
help of flame photometer (AIMIL, Aimil Sales and Agencies
Pvt. Ltd., New Delhi) using appropriate filter and a standard
pattern by taking known concentration of potassium.
Growth Parameters
1. Dry weight of plant
Plants dried at 80 °C for 24 h after the termination of experiment and dry weight was taken per gram of fresh material.
2. Chlorophyll estimation
The optical density of chlorophyll solution read at 645 nm
and 663 nm wave lengths with the help of Spectronic-20
Spectrophotometer (Elico, Elico Ltd. Hyderabad, India).
The chlorophyll contents were calculated according to the
formula given by Arnon (1951) as given below:
Where, O.D. = optical density (absorbance) at given wave
lengths viz. 645 and 663 nm.
V = total volume of chlorophyll extract prepared
in 80 % acetone.
W = fresh weight of plant tissue in g.
Nutrient Uptake
To determine the nutrient uptake of plant the samples were
digested according to Lindner (1944) for the estimation of
N, P, and K.
1. Estimation of nitrogen
The nitrogen was estimated following the method of Lindner
(1944). The solution of standard pattern and samples were
Chlorophyll mg/g of fresh tissue
12.7(O.D.663) 2.69(O.D
a (
)
−
=
. .645) V
W
×
×
1000
ll a (mg/g of fresh tissue) =
12.7 (O.D.663) − 2.69 (O.D.645) × V
1000 × W
Chlorophyll mg/g of fresh tissue
22.9(O.D.645) 4.68 (O.
b(
)
−
=
D D.663) V
W
×
×
1000
ll b (mg/g of fresh tissue) =
22.9 (O.D.645) − 4.68 (O.D.663) × V
1000 × W
Total Chlorophyll mg/g of fresh tissue
20.2 (O.D.645) 8.0
(
)
+
=
2 2 (O.D.663) V
W
×
×
1000
read for their absorbance at 525 nm using Spectronic-20
Spectrophotometer. A calibration pattern was plotted with
optical density on X-axis and known concentration of ammonium sulfate on Y-axis, nitrogen was expressed in terms
of percentage on dry matter bases.
2. Estimation of phosphorus
Phosphorus contents in digested material were estimated by
the method of Fiske and Subbarow (1925). Optical density
of the solution (sample) was read at 625 nm using Spectronics-20 Spectrophotometer. A standard pattern was prepared
using different dilutions of KH 2 PO 4 solution versus optical density. With the help of standard pattern the content of
phosphorus in terms of percentage on dry matter base was
determined.
3. Estimation of potassium
The potassium contents were estimated by Flamephotometer (Elico, Elico Ltd. Hyderabad, India). The readings were
compared with the help of calibration pattern plotted with
the help of known dilutions of KCl solution. The potassium
was expressed in terms of percentage on a dry weight bases.
12.3 Observations
In the present work, impact of 12 detergent cakes and 24
detergent powders commonly sold in the Indian market on
the growth (in terms of dry weight) of selected duckweeds
namely Lemna minor and Spirodela polyrrhiza have been
studied. The growth responses of the selected duckweeds
maintained in small plastic pots containing varying concentrations of all the selected detergents are given below. In both
the weeds three general types of pattern of absolute growth
were observed (as given).
12.3.1 Growth Pattern
There were three general types of absolute growth pattern
as type-A, type-B, and type-C observed in the duckweed
growth treated with 36 selected detergents. Type-A pattern
shows a consistent increase in growth of the duckweed with
increasing concentration of some detergents. The peak of
growth was recorded at 50 ppm level of detergent. Type-B
growth pattern shows an increase in growth up to 30 ppm
and then a decline at higher concentration. In type-C growth
pattern there was an increase in the duckweed growth at
lower dose (10 ppm) of detergents and then it decreased with
further detergent concentration. Type-A pattern of growth resemble with the growth pattern of algal bloom in a medium
with unlimited environment (Kormondy 1994). The growth
pattern type-A is closer to positive linear line between the
growth and detergent concentration. The Lemna minor and
Spirodela polyrrhiza treated with a large number of detergent cakes showed predominantly growth pattern type-A
12 Household Detergents Causing Eutrophication in Freshwater Ecosystems
4. Nitrates
Nitrates were calculated from the standard pattern. Standard
pattern was prepared between concentration of nitrates and
absorbance from 0.0 to 1.0 mg/L of nitrates at the NO 3 -N at
the interval of 0.1 by finding the absorbance of standards.
5. Phosphates
The concentration of phosphate calculated with help of standard pattern. The standard pattern was prepared in the range
of 0.0 to1.0 mg/L of PO 4 -P at the interval of 0.1, following
the same method described for the NO 4 -N.
6. Potassium
The estimation of potassium was carried out directly with the
help of flame photometer (AIMIL, Aimil Sales and Agencies
Pvt. Ltd., New Delhi) using appropriate filter and a standard
pattern by taking known concentration of potassium.
Growth Parameters
1. Dry weight of plant
Plants dried at 80 °C for 24 h after the termination of experiment and dry weight was taken per gram of fresh material.
2. Chlorophyll estimation
The optical density of chlorophyll solution read at 645 nm
and 663 nm wave lengths with the help of Spectronic-20
Spectrophotometer (Elico, Elico Ltd. Hyderabad, India).
The chlorophyll contents were calculated according to the
formula given by Arnon (1951) as given below:
Where, O.D. = optical density (absorbance) at given wave
lengths viz. 645 and 663 nm.
V = total volume of chlorophyll extract prepared
in 80 % acetone.
W = fresh weight of plant tissue in g.
Nutrient Uptake
To determine the nutrient uptake of plant the samples were
digested according to Lindner (1944) for the estimation of
N, P, and K.
1. Estimation of nitrogen
The nitrogen was estimated following the method of Lindner
(1944). The solution of standard pattern and samples were
Chlorophyll mg/g of fresh tissue
12.7(O.D.663) 2.69(O.D
a (
)
−
=
. .645) V
W
×
×
1000
ll a (mg/g of fresh tissue) =
12.7 (O.D.663) − 2.69 (O.D.645) × V
1000 × W
Chlorophyll mg/g of fresh tissue
22.9(O.D.645) 4.68 (O.
b(
)
−
=
D D.663) V
W
×
×
1000
ll b (mg/g of fresh tissue) =
22.9 (O.D.645) − 4.68 (O.D.663) × V
1000 × W
Total Chlorophyll mg/g of fresh tissue
20.2 (O.D.645) 8.0
(
)
+
=
2 2 (O.D.663) V
W
×
×
1000
read for their absorbance at 525 nm using Spectronic-20
Spectrophotometer. A calibration pattern was plotted with
optical density on X-axis and known concentration of ammonium sulfate on Y-axis, nitrogen was expressed in terms
of percentage on dry matter bases.
2. Estimation of phosphorus
Phosphorus contents in digested material were estimated by
the method of Fiske and Subbarow (1925). Optical density
of the solution (sample) was read at 625 nm using Spectronics-20 Spectrophotometer. A standard pattern was prepared
using different dilutions of KH 2 PO 4 solution versus optical density. With the help of standard pattern the content of
phosphorus in terms of percentage on dry matter base was
determined.
3. Estimation of potassium
The potassium contents were estimated by Flamephotometer (Elico, Elico Ltd. Hyderabad, India). The readings were
compared with the help of calibration pattern plotted with
the help of known dilutions of KCl solution. The potassium
was expressed in terms of percentage on a dry weight bases.
12.3 Observations
In the present work, impact of 12 detergent cakes and 24
detergent powders commonly sold in the Indian market on
the growth (in terms of dry weight) of selected duckweeds
namely Lemna minor and Spirodela polyrrhiza have been
studied. The growth responses of the selected duckweeds
maintained in small plastic pots containing varying concentrations of all the selected detergents are given below. In both
the weeds three general types of pattern of absolute growth
were observed (as given).
12.3.1 Growth Pattern
There were three general types of absolute growth pattern
as type-A, type-B, and type-C observed in the duckweed
growth treated with 36 selected detergents. Type-A pattern
shows a consistent increase in growth of the duckweed with
increasing concentration of some detergents. The peak of
growth was recorded at 50 ppm level of detergent. Type-B
growth pattern shows an increase in growth up to 30 ppm
and then a decline at higher concentration. In type-C growth
pattern there was an increase in the duckweed growth at
lower dose (10 ppm) of detergents and then it decreased with
further detergent concentration. Type-A pattern of growth resemble with the growth pattern of algal bloom in a medium
with unlimited environment (Kormondy 1994). The growth
pattern type-A is closer to positive linear line between the
growth and detergent concentration. The Lemna minor and
Spirodela polyrrhiza treated with a large number of detergent cakes showed predominantly growth pattern type-A