pH. Consequently, acidic nature in the soil further reduces the soil microbial
activities (Herpin et al. 2007; Dhananjaya et al. 2009; Selvamurugan et al. 2010).
Several researches proved that wastewater has fertilizer value; it has all necessary
minerals which induce soil health and plant growth. Irrigation with untreated
wastewater may increase soil organic matter, nitrogen, and concentrations of
Na, K, and Ca (Siebe 1998; Angin et al. 2005; Lucho-Constantino et al. 2005;
Mapanda et al. 2005). Singh et al. (2012) reported that adding wastewater to arable
land increased organic matter many folds as compared to control treatment
(Rutkowski et al. 2007). Microbial species and its population help in monitoring
the environment or ecosystem health. Microbial activities are acting as biological
indicators. Biological indicators are assigned to represent the living soil and its
environment. Microbial activities in soil were escalated under sewage effluent
irrigation (Meli et al. 2002; Ramirez-Fuentes et al. 2002; Chaerun et al. 2011).
Soil contains consortia of all major groups of microorganisms, i.e., bacteria, actinomycetes, fungi, and algae. These microorganisms convert toxic organic and inorganic compounds to harmless products, often carbon dioxide, water, etc. They also
affect the microbiological and biological properties of soil like microbial biomass
carbon (MBC) and respiratory rate of the total microbial population. Both short- and
long-term effects of wastewater on soil quality can be monitored by the microbial
metabolic quotient (qCO2) and enzymatic activities (Gianfreda et al. 2005; Adrover
et al. 2012).
However, the long-term application of untreated wastewater in irrigation could
lead to inevitable heavy metal accumulation and a resultant loss of soil character
(Singh et al. 2005; Mapanda et al. 2005; Sharma and De 2007; Jin et al. 2008; Singh
et al. 2012). Mobility and retention of heavy metals are strongly affecting the soil
texture; high clay structure of the soil blocks infiltration of pollutants and causes
Table 8.1 Comparison between treated wastewater and untreated wastewater
Parameter
Treated
wastewater
a
Untreated
wastewater
a
Recommended
standards
pH
8.13
7.50
6.5–8.4
Electrical
Conductivity
1225 μScm
À1.
1032 μScm
À1
0–3000 μScm
À1
Total Dissolved solid
624 ppm
560 ppm
0–2000 ppm
Total nitrogen
61.6 ppm
78.4 ppm
0–10 ppm*
BOD
30 mg/ L
650 mg/L
100 mg/l**
COD
145 mg/L
964 mg/L
–
Sodium
60 ppm
48 ppm
0–40 ppm
Potassium
20 ppm
24 ppm
0–2 ppm
a Data source: Alghobar and Suresha (2015)
*Laboratory determinations needed to evaluate common irrigation water quality problems (FAO
1985)
**Standard shall be applicable for industries, operations, or processes other than those industries,
operations, or processes for which standards have been specified in Schedule of the Environmental
Protection Rules, 1989
182
Monika et al.
activities (Herpin et al. 2007; Dhananjaya et al. 2009; Selvamurugan et al. 2010).
Several researches proved that wastewater has fertilizer value; it has all necessary
minerals which induce soil health and plant growth. Irrigation with untreated
wastewater may increase soil organic matter, nitrogen, and concentrations of
Na, K, and Ca (Siebe 1998; Angin et al. 2005; Lucho-Constantino et al. 2005;
Mapanda et al. 2005). Singh et al. (2012) reported that adding wastewater to arable
land increased organic matter many folds as compared to control treatment
(Rutkowski et al. 2007). Microbial species and its population help in monitoring
the environment or ecosystem health. Microbial activities are acting as biological
indicators. Biological indicators are assigned to represent the living soil and its
environment. Microbial activities in soil were escalated under sewage effluent
irrigation (Meli et al. 2002; Ramirez-Fuentes et al. 2002; Chaerun et al. 2011).
Soil contains consortia of all major groups of microorganisms, i.e., bacteria, actinomycetes, fungi, and algae. These microorganisms convert toxic organic and inorganic compounds to harmless products, often carbon dioxide, water, etc. They also
affect the microbiological and biological properties of soil like microbial biomass
carbon (MBC) and respiratory rate of the total microbial population. Both short- and
long-term effects of wastewater on soil quality can be monitored by the microbial
metabolic quotient (qCO2) and enzymatic activities (Gianfreda et al. 2005; Adrover
et al. 2012).
However, the long-term application of untreated wastewater in irrigation could
lead to inevitable heavy metal accumulation and a resultant loss of soil character
(Singh et al. 2005; Mapanda et al. 2005; Sharma and De 2007; Jin et al. 2008; Singh
et al. 2012). Mobility and retention of heavy metals are strongly affecting the soil
texture; high clay structure of the soil blocks infiltration of pollutants and causes
Table 8.1 Comparison between treated wastewater and untreated wastewater
Parameter
Treated
wastewater
a
Untreated
wastewater
a
Recommended
standards
pH
8.13
7.50
6.5–8.4
Electrical
Conductivity
1225 μScm
À1.
1032 μScm
À1
0–3000 μScm
À1
Total Dissolved solid
624 ppm
560 ppm
0–2000 ppm
Total nitrogen
61.6 ppm
78.4 ppm
0–10 ppm*
BOD
30 mg/ L
650 mg/L
100 mg/l**
COD
145 mg/L
964 mg/L
–
Sodium
60 ppm
48 ppm
0–40 ppm
Potassium
20 ppm
24 ppm
0–2 ppm
a Data source: Alghobar and Suresha (2015)
*Laboratory determinations needed to evaluate common irrigation water quality problems (FAO
1985)
**Standard shall be applicable for industries, operations, or processes other than those industries,
operations, or processes for which standards have been specified in Schedule of the Environmental
Protection Rules, 1989
182
Monika et al.