- Email: [email protected]
Growth and mineral accumulation in Eucalyptus camaldulensis seedlings irrigated with mixed industrial effluents
Bioresource Technology 88 (2003) 221–228
Growth and mineral accumulation in Eucalyptus camaldulensis seedlings irrigated with mixed industrial effluents M. Bhati, G. Singh
*
Division of Forest Ecology and Desert Development, Arid Forest Research Institute, New Pali Road, Jodhpur 342005, India Received 21 March 2002; received in revised form 20 September 2002; accepted 1 December 2002
Abstract Effects of mixed industrial effluents on growth, dry matter accumulation and mineral nutrient in Eucalyptus camaldulensis seedlings were studied. The objective was to evaluate the adaptability of E. camaldulensis to effluent, tolerance to excess/deficiency of mineral elements and ultimately to determine suitable combinations of industrial/municipal effluent for their use in biomass production in dry areas. Different irrigation treatments were: T1 : good water; T2 : municipal effluent; T3 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. High concentrations of metal ions and low concentrations of Ca, Mg, K, Na, N and P in soil and seedlings of T4 resulted in mortality of the seedlings within a few days. Addition of the textile/ municipal effluent increased the survival time of the seedlings for two to three months in T6 , T7 and T8 treatments. Among the remaining treatments, the seedlings of T2 attained 131 cm height, 1.97 cm collar diameter, 19 total branches and produced 158 g seedling1 of dry biomass at the age of 10 months. The seedling of T3 produced the least growth and biomass. Growth equivalent to that of the seedlings of T1 treatment was achieved when municipal effluent was mixed with textile effluent (T5 ). There was a decrease in soil pH, EC, SOC, NH4 –N, NO3 –N, PO4 –P and basic cations and increase in the concentration of Cu, Fe, Mn and Zn with T4 treatment. The reverse trend was observed in T3 where a high concentration of Na might have reduced Mg and micronutrient concentration in seedlings potentially affecting root and leaf growth. Mixing of effluents may be useful in tree irrigation to increase biomass productivity, which is evidenced by improved growth in T5 and survival in T6 , T7 and T8 treatments. Further, reduction of toxic concentration of metal ions in effluents may be helpful for a long-term field application. Ó 2002 Elsevier Science Ltd. All rights reserved. Keywords: Arid region; Metal accumulation; Mixed industrial effluents; Tree seedling irrigation; Wastewater quality
1. Introduction Increasing industrialization and urbanization has not only deprived production of crops through land degradation but also remained mute witness to the continuous loss of our precious water resources (Zekri and Koo, 1994). Attempts have been made to reverse the process of this degradation with afforestation with fast growing tree species and disposal of wastewater safely and economically to tree plantations (Bielorai et al., 1984; Feigin et al., 1984). The goal of such endeavours against severe odds is the successful greening of wasteland. The resultant woodland has an appreciable protective action by absorption/uptake of harmful heavy metals from soil
*
Corresponding author. Tel.: +91-0291-742550. E-mail address: [email protected] (G. Singh).
through development of an extensive root system. This reduces the toxicity of the soil and plays an important role to safeguard the environment (Stewart et al., 1990; Cromer et al., 1987). The effluent from different industrial sources has different impacts on the biological system, particularly plants because of different chemical constituents. Mixing of different effluents of different characteristics and their disposal in tree irrigation may be one of the best management options. Eucalyptus camaldulensis was selected for this study because of its important attributes such as tolerance to a wide range of soil type, and pH and rapid growth and high wood yield for timber and fuel wood. It is helpful to recapitulate the soil status and quality (Abo-Hassan et al., 1988). The present investigation was undertaken with the view that mixing of different industrial effluents among each other or with municipal effluent in varying proportions may bring about favorable changes in chemical
0960-8524/03/$ - see front matter Ó 2002 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0960-8524(02)00317-6
222
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
composition. Utilization of mixed effluents may be beneficial for improving soil health and for enhancing growth and biomass production of the tree seedlings. This kind of practice may come up as an alternative forestry/agroforestry-related water technology for irrigation in water and biomass scarce areas. Disposal of effluents to land sometimes results in mortality of plants due to accumulation of metal ions. Therefore, another aspect of this study was to determine the optimum level of application to avoid injury to plants.
2. Methods 2.1. Site description The experiment was conducted at the Arid Forest Research Institute, Jodhpur (72.030 E, 26.450 N). The experiment was done in plastic pots with mean diameters of 35 cm and heights of 55 cm. The soil in each pot was loamy sand (coarse loamy, mixed, hyperthermic family of typic camborthides according to US soil taxonomy) and with a water holding capacity of 9.88% (w/ w) at 0.03 MPa. The soil had 91.5% sand, 7.13% silt and 1.37% clay. Twenty-two kg soil was transferred to each pot and filled up to 50 cm leaving a height of 5 cm for irrigation. Air-dried and sieved soil samples were analyzed for physiochemical properties. Soil nutrient data of July 1999 (before plantation) indicated that this soil was poor in organic carbon (0.13%), NH4 –N (2.17 mg kg1 ), NO3 –N (1.56 mg kg1 ) and PO4 –P (6.00 mg kg1 ). DTPA extractable Mn, Fe, Cu and Zn were 3.30, 2.36, 0.26 and 0.57 mg kg1 . Soil pH and electrical conductivity (EC) in 1:2 soil water suspensions were 7.8 and 0.76 dS m1 , respectively. 2.2. Seedling establishment Six-month old seedlings of E. camaldulensis from a single provenance were planted in August 1999 to provide one seedling per pot. Wastewater application was initiated in September 1999 after proper establishment of the seedlings. Eight treatments were T1 : good water (canal water); T2 : municipal effluent; T3 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. Steel effluent is released after washing of iron sheets using nitric acid, sulphur and hydrofluoric acid in iron rolling mills. Textile effluent is released after washing of excess dyes of printed cloths from the dyeing and printing factories using guar gum (obtained from Cymopsis tetragonoloba), sodium hypochlorite, sodium silicates and detergents. These effluents were obtained from the industries in Jodhpur and municipal effluent from a source point
passing through the experimental field. Samples were collected and brought to the laboratory in resistant plastic bottles to avoid adherence to the container wall. They were stored at 4 °C to minimize microbial decomposition of solids. The experiment was conducted as a complete randomized design with three replications. Seedlings were irrigated to maintain the soil water availability between 80% and 100% of field capacity. Total quantity of effluents added were 63 l in T1 , T2 , T3 and T5 treatments in 27 irrigation events, 2 l in T4 in one irrigation event and 14 l in T6 and T8 in six irrigation events and 19 l in T7 treatments in nine irrigation events. The above variations in quantity and irrigation events were due to seedling mortality after which the irrigation was discontinued in that particular treatment. 2.3. Data collection Height, collar diameter and number of branches were recorded at one month intervals to measure the magnitude of response to different types of industrial/municipal effluents. Plants were harvested when the seedlings of T5 treatment became leafless (i.e., at 10 months of age) for an estimation of biomass production and partitioning. Leaves were separated and the total number of leaves counted and weighed to record fresh weight. Shoots removed from the collar region were measured for shoot length and collar diameter and fresh weights were recorded. Roots along with soil mass were removed from the pots by turning the pots upside down and roots were separated carefully and soil particles adhering to the root surface were removed. Primary and secondary root were measured for length and diameters using tape and vernier caliper. For secondary roots five largest roots were measured and averaged. Numbers of roots were also counted. Fresh weight of root was recorded immediately after measurement. Dry weights of the leaves, shoot and roots were recorded after oven drying of samples for 72 h at 80 °C. Root volume was measured by a water replacement method (Singh, 2001). 2.4. Chemical analysis Irrigation quality criteria, including total solids (TS), total suspended solids (TSS) and other parameters listed in Table 1, of raw municipal effluent, industrial effluents and good water were assessed using standard procedures (APHA, 1975; OMA, 1990). Concentrations of metals were estimated to assess any metals hazards in the effluent (Griepink et al., 1984). Dried leaves, shoot and roots of the seedlings were ground to pass through a 2 mm sieve and digested with triacid mixture (HNO3 : H2 SO4 :HClO4 in 10:4:1 ratio) (Jones and Case, 1990). The N and P contents were determined after wet digestion with 12 ml H2 SO4 using two Kjeltab (Cu/3.5) at
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
223
Table 1 Physico-chemical characteristics of different kinds of effluent QP
T1
T2
T3
T4
T5
T6
T7
T8
pH EC (dS m1 ) TS (mg l1 ) TSS (mg l1 ) TDS (mg l1 ) SAR DO (mg l1 ) BOD (mg l1 ) COD (mg l1 ) K (mg l1 ) Ca (mg l1 ) Mg (mg l1 ) Cl (mg l1 ) Na (mg l1 ) NH4 –N mg l1 NO3 –N mg l1 PO4 –P (mg l1 ) Cu (mg l1 ) Fe (mg l1 ) Mn (mg l1 ) Zn (mg l1 )
7.6 0.20 356 6.7 139 0.08 6.5 2.0 8.0 20 95 49 7.56 4.20 2.1 0.020 0.02 0.003 0.08 0.022 0.017
7.80 0.93 783 156 629.5 0.15 2.20 76.0 190 32 256 156 210 12.50 8.5 0.520 12.30 0.26 3.64 0.32 0.48
9.5 4.30 4100 2000 2800 6.25 12.8 45.0 300 40 28 6 18.46 139.5 0.03 0.001 16.39 Nil Trace Nil Nil
1.4 7.86 8800 7500 5000 0.07 – – 74,830 3 26 7 756 1.50 0.02 0.001 4.23 91 320 280 375
8.4 2.07 1850 500 1350 0.63 8.0 80 290 16 186 98 50.64 42.50 3.2 0.210 13.25 0.06 0.97 0.08 0.21
4.5 5.90 6650 1650 3500 0.08 0.42 20,250 17,800 6 27 10 690 1.75 0.02 0.003 1.24 40.00 100.00 80.00 110.00
4.70 4.90 6500 1560 4940 0.05 0.78 17,250 18,320 8 24 7 675 1.07 0.01 0.002 1.25 35.00 60.00 48.00 75.00
4.60 6.83 5650 1850 3800 0.04 0.50 20,560 25,680 4 25 9 623 0.97 0.01 0.001 1.15 42.00 96.00 78.00 100.25
T1 : good water; T2 : municipal effluent; T4 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. QP: quality parameters; EC: electrical conductivity; TS: total solid; TSS: total suspended solid; TDS: total dissolved solid; SAR: sodium adsorption ratio; DO: dissolved oxygen; BOD: biochemical oxygen demand, and COD: chemical oxygen demand.
350 °C for half an hour, using UV–VIS spectrophotometer (Systronix model 117) at 490 and 420 nm, respectively (Jackson, 1973). Soil pH and EC were determined in 1:2 soil: water ratio. Soil organic matter was determined by the partial oxidation method (Walkey and Black, 1934). Available nitrogen was determined after 2 M KCl extraction using a Tecator Model Enviroflow––5012 autoanalyser. Extractable phosphorus was determined by OlsonÕs extraction method (Jackson, 1973). For determination of macro and micronutrients, soil samples were extracted with 0.1 N HCl and DTPA solution, respectively (Jackson, 1973). Ca, Mg, Cu, Zn, Mn and Fe were estimated in absorption mode and K and Na in emission mode using a Perkin–Elmer (Model3110) double beam atomic absorption spectrophotometer.
2.5. Statistical analysis Data were statistically analyzed using an SPSS package (Lindaman, 1992). Since the experiment was conducted as a complete randomized design, variation over treatments was studied using a one-way ANOVA model with average growth parameters and plant nutrients as dependent variables. Treatments were considered as the fixed effect and within treatment variation as the error.
3. Results 3.1. Effluents characteristics Textile effluent had high pH and EC. Steel effluent and its mixture were acidic in nature but with high EC (Table 1). Dissolved oxygen was almost absent in the steel effluent whereas it was less than 1 mg l1 in the effluents involving steel effluent in different combinations. Municipal effluent exhibited low dissolved oxygen levels when compared with good water. Biochemical oxygen demand (BOD) and chemical oxygen demand (COD) were within the permissible limits except in T4 , T6 , T7 and T8 treatments where they were excessively high (ISI, 1987). TS, TSS and total dissolved solid (TDS) were high in textile effluent, pure steel effluent and mixed effluent (Table 1). Chloride was low in T1 , T2 , T3 and T5 compared to the other treatments. The effluents in T3 , T4 , T6 , T7 and T8 had low Ca and Mg. Metal concentrations were very low in textile effluent, but high in T4 , T6 , T7 and T8 treatments. 3.2. Seedling survival and growth Seedlings of T4 treatment died within two days of steel effluent application. However, the seedlings of T6 , T7 and T8 treatments survived to the age of 2–3 months. Of the eight treatments, seedlings of E. camaldulensis in
224
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
Table 2 Growth of E. camaldulensis seedlings irrigated with different kinds of effluents T T1 T2 T3 T5 P
Initial
10 months
H
CD
NB
H
CD
NB
50 (2.6) 50 (2.5) 51 (2.8) 50 (2.5) >0.05
0.97 (0.03) 0.93 (0.02) 0.87 (0.12) 0.77 (0.12) >0.05
7 (0.1) 11 (2.1) 9 (0.4) 7 (0.1) >0.05
116 (5.8) 131 (4.0) 94 (2.1) 128 (7.8) <0.01
1.87 (0.22) 1.97 (0.03) 1.30 (1.52) 1.47 (0.02) <0.01
9 (1.5) 19 (2.0) 12 (0.3) 11 (0.3) <0.01
T1 : good water; T2 : municipal effluent; T3 : textile effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio. T: treatment; H: height; CD: collar diameter, NB: number of branches. Values are mean of three replication with SEm in parentheses.
T1 , T2 , T3 and T5 treatments survived to the end of the experiment. Initial height, collar diameter and number of branches (September, 1998) did not differ ðP > 0:05Þ among the treatments. However, at the age of 10 months, the seedlings attained 94 cm (T3 ) to 131 cm (T2 ) height (Table 2). Seedlings subjected to T2 treatment had 13% greater height and 5% greater collar diameter than that of T1 treatment. The minimum growth was in T3 among T1 , T2 , T3 and T5 treatments. The increment in T5 over T3 was 36% and 13% for height and collar
diameter. Number of branches was also high ðP < 0:05Þ among the seedlings of different treatments. 3.3. Root growth Number, length, diameter, and volume of primary and secondary root differed significantly ðP < 0:05Þ under the influence of different treatments (Table 3). Seedlings of T2 attained 2.8 times larger root length when compared with T1 treatment. Seedlings of T3
Table 3 Root growth (cm) of 10 months old E. camaldulensis seedlings irrigated with different kinds of effluents Treatment
RL
RD
SR
SL
RV
T1
35 (1.21) 98 (3.51) 29 (4.51) 49 (5.61) <0.01
1.9 (0.02) 2.5 (0.06) 1.0 (0.05) 1.5 (0.03) <0.01
32.00 (2.13) 40.00 (3.52) 31.00 (2.56) 33.00 (3.21) <0.01
33 (0.99) 59 (0.67) 23 (1.85) 42 (1.73) <0.01
87 (2.56) 132 (3.21) 32 (3.56) 60 (3.21) <0.01
T2 T3 T5 P -value
T1 : good water; T2 : municipal effluent; T3 : textile effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio. RL: primary root length; RD: root diameter; SR: number of secondary roots; SL: secondary root length; RV: root volume. Values are mean of three replications with SEm in parentheses.
Table 4 Dry biomass (g seedling1 ) of 10 months old E. camaldulensis seedlings irrigated with different kinds of effluent Treatment
Leaves
Shoot
Root
Total
R/S ratio
Canal water
25 (2.1) 37 (3.2) 13 (4.3) 23 (1.2) <0.01
39 (2.1) 68 (4.6) 27 (2.4) 48 (2.5) <0.01
38 (3.9) 54 (3.4) 14 (1.3) 37 (2.1) <0.01
102 (2.9) 158 (6.6) 54 (1.4) 107 (3.2) <0.01
0.59 (0.004) 0.51 (0.05) 0.35 (0.06) 0.49 (0.02) <0.05
Municipal effluent Textile effluent Textile þ municipal P -value
T1 : canal water; T2 : municipal effluent; T3 : textile effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio. R/S: root biomass to above ground biomass ratio. Values are mean of three replication with SEm in parentheses.
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
treatment had thinner and fewer roots compared to the seedlings of other treatments, which survived for 10 months. Differences in numbers of secondary roots were not significant between the seedlings of T1 , T3 and T5 treatments. Root volume was 52% higher in the seedlings of T2 , whereas it was low in the seedlings of T3 treatment, as compared to that in T1 treatment. 3.4. Biomass T2 treatment resulted in a 1.5 times increase in total dry biomass than that of the seedlings in T1 treatment (Table 4). The increase was 80% in the leaf, 54% in the shoot and 42% in the root. Seedlings of T3 treatment
225
produced the least amount of dry biomass and the reduction was 40% in the leaf, 30% in the shoot and 63% in the root biomass when compared with the seedlings of T1 treatment. However, there was twice the biomass for the seedlings of T5 as compared to that in T3 . The biomass of different plant parts varied significantly among the treatments. Biomass in leaves varied from 21% in T5 to 25% in T1 treatment. Contribution of shoot biomass was high ðP < 0:001Þ in the seedlings of T3 treatment but it was low in T1 treatment. Percent root biomass varied from 26% in the seedlings of T3 treatment to 37% in the seedlings of T1 treatment. Root to shoot ratio was low for the seedlings of T3 treatment and increased up to 0.59 in the seedlings of T1 treatment. Addition of
Table 5 Nutrient composition in different part of E. camaldulensis seedlings irrigated with different effluents Treatment Leaves T1 T2 T3 T4 T5 T6 T7 T8 P -value Roots T1 T2 T3 T4 T5 T6 T7 T8 P -value
N
P
K
Ca
Mg
Na
Cu
Fe
Mn
Zn
20.81 (3.21) 31.56 (5.21) 10.51 (0.32) 2.76 (0.13) 17.89 (1.10) 3.67 (0.11) 3.99 (0.12) 4.16 (0.21)
2.90 (0.11) 4.50 (0.41) 1.09 (0.21) 1.20 (0.11) 1.98 (0.11) 1.40 (0.32) 1.80 (0.21) 2.00 (0.53)
10.78 (1.02) 17.37 (0.56) 8.78 (0.09) 4.78 (1.21) 11.98 (0.12) 4.97 (1.01) 4.99 (1.03) 4.98 (0.98)
11.17 (0.56) 19.78 (0.06) 10.91 (0.05) 6.87 (1.12) 12.89 (0.08) 6.78 (1.62) 6.91 (1.02) 6.79 (2.01)
3.07 (0.08) 5.74 (1.02) 0.60 (0.02) 1.32 (0.12) 2.78 (0.02) 1.41 (0.21) 1.41 (0.35) 1.60 (0.33)
1.46 (0.05) 1.39 (0.31) 2.67 (0.33) 0.70 (0.21) 1.79 (0.05) 0.77 (0.12) 0.77 (0.25) 0.79 (0.21)
16.97 (1.020) 23.67 (1.25) 2.96 (0.52) 48.75 (5.26) 10.97 (2.12) 40.71 (5.23) 40.87 (5.26) 40.30 (6.25)
453.67 (50.12) 781.67 (2.63) 140.51 (2.36) 1710.5 (12.45) 590.71 (23.56) 1251.7 (6.52) 1351.7 (21.65) 1000.5 (52.62)
190.80 (12.05) 390.40 (3.25) 100.71 (3.25) 680.60 (21.56) 110.71 (5.67) 510.70 (5.48) 515.70 (25.64) 507.5 (12.56)
44.67 (10.21) 68.10 (2.03) 21.82 (5.62) 140.67 (20.12) 41.67 (6.23) 110.70 (7.45) 100.71 (8.56) 110.71 (10.25)
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
6.47 (1.61) 8.67 (2.52) 3.46 (2.13) 1.56 (0.52) 6.16 (2.10) 1.45 (0.22) 1.58 (0.53) 1.60 (0.22)
0.99 (0.22) 1.10 (0.21) 0.40 (0.10) 0.61 (0.12) 0.67 (0.11) 0.60 (0.12) 0.62 (0.21) 0.62 (0.11)
4.35 (0.01) 5.68 (0.02) 1.41 (0.05) 0.73 (0.03) 4.49 (0.15) 0.70 (0.06) 0.70 (0.06) 0.72 (0.15)
3.89 (0.05) 5.09 (0.05) 1.92 (0.06) 1.72 (0.21) 3.99 (0.36) 1.87 (0.13) 1.87 (0.13) 1.89 (0.25)
2.01 (0.03) 1.97 (0.31) 0.27 (0.06) 0.87 (0.12) 0.99 (0.13) 0.91 (0.20) 0.91 (0.11) 0.99 (0.12)
0.83 (0.02) 0.51 (0.05) 0.99 (0.12) 0.42 (0.08) 0.89 (0.15) 0.52 (0.05) 0.55 (0.15) 0.50 (0.16)
5.79 (1.00) 9.71 (1.25) 1.39 (0.52) 32.06 (2.23) 5.89 (0.36) 27.89 (5.26) 29.67 (6.25) 28.78 (2.45)
140.81 (5.62) 267.10 (3.21) 42.15 (3.12) 806.70 (10.25) 141.67 (0.65) 716.70 (6.52) 678.70 (8.74) 609.70 (10.25)
120.71 (10.25) 185.10 (2.12) 32.68 (5.21) 303.67 (2.65) 110.72 (2.56) 295.40 (12.56) 280.15 (6.52) 281.50 (10.45)
28.76 (2.56) 31.53 (2.65) 6.79 (1.21) 92.71 (10.23) 19.79 (2.31) 87.58 (6.48) 85.86 (10.23) 88.71 (7.54)
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
T1 : good water; T2 : municipal effluent; T3 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. Values are mean of three replications with SEm in parentheses. N, P, K, Ca, Mg, Na are in g kg1 and Cu, Fe, Mn, Zn are in mg kg1 .
226
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
municipal effluent to textile effluent (T5 ) increased the root/shoot ratio to 0.49.
ment. However, the soil of T4 , T6 , T7 and T8 exhibited a drastic reduction in soil pH and EC. A two-fold increase in SOC was observed in the soil of T2 treatment whereas it decreased by 31% in T3 treatment. SOC was reduced drastically to 54% in T4 and 31% in soil of T7 treatment. NH4 –N and NO3 –N did not differ in soil of T1 , T2 and T5 treatments but were high ðP < 0:05Þ as compared to their initial concentrations (Table 6). Soil of T4 , T6 , T7 and T8 treatment had approximately 50% lower NH4 –N and NO3 –N when compared with that of T1 , T2 , T3 and T5 treatments. Increase in the PO4 –P concentration occurred more in soil of T3 treatment, whereas the soil of T4 , T6 , T7 and T8 treatment were almost similar in their concentrations. PO4 –P concentration was significantly lower in the soil of T1 treatment. Concentration of Na, Ca and Mg did not differ between T2 and T1 treatment but K increased by 70%. In soil of T5 treatment, Na increased by 30% and K by 84% over the initial concentration whereas Ca and Mg did not differ. However, the soil from T4 , T6 , T7 and T8 treatments displayed significantly low K, Ca and Mg concentrations. DTPA extractable Cu, Fe, Mn and Zn increased with continuous addition of effluent as compared to good water irrigation. T3 was the only treatment, the soil of which had low micronutrients concentration. The increase in Cu in soil of T2 and T5 treatment was approximately 4.9 and 3.9 fold, respectively, whereas it increased considerably in the soil of T4 , T6 , T7 and T8 treatments when compared to its initial concentration. Fe concentration increased from 4.9 fold in T2 to 60.0 fold in T4 treatment. Mn concentration in the soil of T2
3.5. Plant mineral composition Mineral element concentrations in seedlings differed significantly ðP < 0:01Þ both due to the seedling parts and treatments (Table 5). Leaves had the highest concentration of nutrients followed by shoot and roots in all the eight treatments under study. N, P, K, Ca and Mg concentrations were high in the seedlings of T2 followed by T1 except in root in which Mg concentration was high in the seedlings of T1 . Concentrations of Cu, Zn, Mn and Fe were drastically high in the seedlings of T4 , T6 , T7 and T8 , which received steel effluent and its combination. Concentration of N, P, K and Ca was low in these treatments. Concentration of Na was significantly high in the seedlings of T3 . It was reduced to its lowest value in T4 treatment. The trend of Mg was reverse to that of Na in the seedlings of T3 treatment. Seedlings of T2 treatment had high concentration of these mineral elements except Na among the surviving treatments (T1 , T2 , T3 and T5 ). 3.6. Soil properties Effluent irrigated soil had high (P < 0:01) pH, EC, soil organic carbon (SOC), NH4 –N, NO3 –N, PO4 –P, Cu, Fe, Mn and Zn as compared to good water irrigated soil. Increase in pH was 1.3 unit and EC by 7 times in soil of T3 treatment compared to the soil of T1 treat-
Table 6 Changes in soil properties under the influence of different kind of effluent application planted with E. camaldulensis seedlings Treatment
pH
Initial
7.60 0.65 0.13 (0.03) (0.05) (0.005) 7.60 0.67 0.13 (0.02) (0.03) (0.02) 7.90 0.67 0.23 (0.02) (0.03) (0.06) 8.86 3.82 0.09 (0.02) (0.06) (0.006) 4.50 0.25 0.04 (0.03) (0.02) (0.01) 7.92 1.92 0.12 (0.02) (0.05) (0.006) 4.90 0.25 0.09 (0.02) (0.03) (0.006) 4.80 0.26 0.10 (0.04) (0.03) (0.01) 5.20 0.26 0.09 (0.04) (0.03) (0.006) <0.01 <0.01 <0.01
T1 T2 T3 T4 T5 T6 T7 T8 P -value
EC
SOC (%)
NH4 –N
NO3 –N
PO4 –P
K
Ca
Mg
6.00 (0.07) 6.00 (0.07) 6.23 (0.04) 4.14 (0.08) 2.80 (0.07) 5.97 (0.05) 2.86 (0.03) 3.13 (0.06) 3.01 (0.03) <0.01
1.40 (0.03) 1.40 (0.04) 1.50 (0.03) 1.61 (0.04) 0.65 (0.02) 1.41 (0.04) 0.67 (0.03) 0.69 (0.02) 0.61 (0.02) <0.01
5.00 (0.09) 5.00 (0.12) 10.80 (0.17) 12.50 (0.32) 4.20 (0.13) 11.40 (0.23) 5.00 (0.10) 5.00 (0.10) 5.50 (0.08) <0.01
0.08 (0.004) 0.08 (0.005) 0.13 (0.002) 0.20 (0.011) 0.06 (0.003) 0.14 (0.004) 0.06 (0.002) 0.07 (0.005) 0.06 (0.002) <0.01
10.75 (0.18) 10.39 (0.26) 11.17 (0.15) 8.64 (0.23) 6.32 (0.20) 10.09 (0.12) 6.34 (0.13) 6.46 (0.14) 6.40 (0.06) <0.01
0.25 0.97 (0.013) (0.07) 0.25 0.89 (0.019) (0.06) 0.27 0.97 (0.006) (0.05) 0.19 2.55 (0.009) (0.04) 0.15 0.19 (0.005) (0.02) 0.25 1.26 (0.021) (0.04) 0.16 0.13 (0.008) (0.04) 0.17 0.14 (0.004) (0.03) 0.15 0.14 (0.005) (0.02) <0.01 <0.01
Na
Cu 0.26 (0.01) 0.26 (0.01) 1.26 (0.07) 0.16 (0.03) 45.62 (1.67) 1.01 (0.05) 45.91 (1.61) 37.27 (0.93) 38.90 (1.79) <0.01
Fe
Mn
2.36 3.30 (0.06) (0.11) 2.30 3.00 (0.07) (0.10) 11.53 10.00 (0.68) (0.38) 2.23 3.20 (0.05) (0.07) 190.60 135.50 (7.39) (3.17) 5.60 7.87 (0.40) (0.12) 127.84 145.35 (5.36) (3.26) 123.53 94.95 (11.76) (2.41) 168.90 155.30 (6.30) (3.42) <0.01 <0.01
Zn 0.57 (0.04) 0.51 (0.03) 1.82 (0.05) 0.50 (0.02) 90.52 (2.86) 1.72 (0.02) 46.78 (1.32) 32.15 (2.33) 45.70 (1.74) <0.01
T1 : good water; T2 : municipal effluent; T3 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. Values are mean of three replication with SEm in parentheses. EC is in dS m1 ; K, Ca, Mg and Na are in g kg1 and the rest are in mg kg1 .
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
and T5 treatments increased by 2.4 fold whereas the increase was 41.0 fold in T4 and 16.5 fold in the soils of T6 , T7 and T8 treatments. Zn accumulation was almost three fold in the soils of T2 and T5 treatments when compared to the soil of T1 treatment. The increase was very high in the soil of T4 , T6 , T7 and T8 treatments. Increase in concentrations of these micronutrients in soil of T1 treatment was also observed compared to their initial concentrations.
4. Discussion Immediate mortality in the seedlings under exogenously supplied steel effluent was probably due to heavy metals toxicity. It is evident by the high concentration of Cu, Fe, Mn and Zn observed in plants and soil. This is in agreement with the finding that high concentration of metals is toxic to plants (Woolhouse, 1983; Baker, 1987; Macnair, 1993). High metal concentration affects mobilization and balanced distribution of essential elements among different plant parts via competitive uptake (Clarkson and Luttge, 1989; Schat and Ten Bookum, 1992). It results in mortality of the seedlings. Survival extension of the seedling in T6 , T7 and T8 treatments up to two to three months may be due to decreased loading of heavy metal and addition of major essential plant nutrients through the mixing of the textile and municipal effluent. Marked difference in growth and biomass production under different kinds of effluent application may be due to variations in chemical constituents, particularly metal ions. Restricted growth by the seedlings irrigated with pure textile effluent (T3 ) was attributed to high sodium concentration as evidenced by high value of SAR and low concentration of bivalent Ca and Mg in this effluent. It may partly also be due to high TS, TSS and TDS which might have affected the osmotic relations of the seedlings (Swaminathan and Vaidheeswaran, 1991). The enhanced salinity and conductivity of the solutes might have caused Mg deficiency as evidenced by low Mg in plant parts, though the concentration of micronutrients was also low. Mixing of the municipal effluent in the textile effluent resulted in stimulation of growth and biomass production. This suggests that the toxic effect of textile effluent may be reduced by mixing of municipal effluent and addition of mineral elements particularly Mg and micronutrients. It might have also made some favourable changes in soil plant water matrix. Greater growth and biomass production of the seedlings of T2 treatment may be due to sufficient availability of water and essential elements. High leaf biomass in the seedlings of T2 treatment is obviously due to addition of nitrogen and phosphorus through municipal effluent addition. However, higher proportion of biomass in shoot in the seedlings of T3 treatment is
227
probably due to decreased leaf and root biomass. The discrepancy in nutrient concentration and uptake in E. camaldulensis may arise due to water and nutrient supply. Higher concentration of Cu, Fe, Mn and Zn and low concentration of Na, K, Ca, Mg, N and P in perennial parts of the seedlings irrigated with steel effluent and the allied mixtures might be due to low pH, increasing solubility of metals ions resulting in excess metal affecting absorption and translocation of basic cations (Malkanathi et al., 1995). Low concentration of Cu, Zn, Mn, Fe, Ca, Mg and K in the seedlings of T3 treatment was probably due to low availability of these ions in textile effluent (Table 1). Perhaps, high concentration of Na ion showed complementary competition for absorption of these ions under increased soil salinity and decreased water availability. Significant decrease in SOC in T4 , T6 , T7 and T8 was believed to be due to loss of organic acids of humic origin from the soil (Dillon et al., 1987). Decreased availability of Ca, Mg, K and Na may be due to leaching losses of these ions in low pH (Reuss et al., 1987). Greater increases in pH under T3 was due to the alkaline nature of textile effluent with high concentrations of Na (Willett et al., 1984). The decrease in micronutrient concentration was due to increase in soil alkalinity and/ or their less availability in textile effluent. With increased alkalinity, Na might induce the deficiency of Cu, Fe, Mn, Zn, Ca and Mg as observed by seedling nutrient analysis. Deficiency of Cu, Mn, Fe and Zn has also been observed in Eucalyptus planted in calcareous soil irrigated with effluent of high pH (Stewart et al., 1981). It is also supported by the less growth and low nutrient uptake in response to this treatment. Improvement in soil of T5 treatment might be due to addition of municipal effluent as shown by increased availability of micronutrient and Mg in soil and seedlings of T5 treatment. Increased soil availability of PO4 –P, K, Ca, Cu, Fe, Mn and Zn in T2 might be due to their addition through municipal effluent in spite of their high uptake by the growing plants. The study of Mitra and Gupta (1999) on nutrients and heavy metal status indicated that Cu, Fe, Mn and Zn increased with increase in quantity of municipal effluent irrigation. Baddesha et al. (1997) have also reported that irrigation of soil under Eucalyptus plantation with sewage water increased the macro and micronutrient concentration. The result of the present study demonstrated that concentration of Na was less in sewage-irrigated soil compared to good water. 4.1. Conclusion and recommendation The study suggests that steel effluent was toxic to the seedlings because of high concentration of metal ions, which accumulated in soil and seedling parts. Low pH influenced the metal mobilization as evidenced by high concentration of the metal ions and reciprocally low
228
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
concentration of basic cations, N and P in seedlings. Combinations of steel effluent also exhibited a lethal effect, but seedling survival up to 3 months is indicative of favourable changes in chemical composition after addition of textile and municipal effluents. Pure textile effluent affected the root and leaf growth adversely, which may be because of Na-induced Mg and micronutrients deficiency. Addition of municipal effluent to textile effluent improved the growth, biomass and nutritional status of E. camaldulensis seedlings. It is recommended as one of the better options for utilization of textile industrial effluent in tree growing. Seedlings irrigated with municipal effluent showed optimum growth and plant nutrient concentration. It may be used as an optimal strategy for raising woodlot to supply fuel wood in vicinity of a suburban area. However, reduction of toxic concentration of metal ions in effluents may be helpful for their long-term field application. Acknowledgements Authors are thankful to the Director Arid Forest Research Institute, Jodhpur for providing research facilities. One of us (MB) thanks ICFRE, Dehradun for the award of JRF/SRF. References APHA, AWWA, WPCF, 1975. Standard method for the examination of water and wastewater, 14th edn. American Public Health Association, Washington, USA. Abo-Hassan, A., Kandeel, S.A., Kherallah, I.E., 1988. New eucalypt species introduction in the Saudi Arabia central zone. In: Proceedings of the International Forestry Conference, Australian Bicentenary, vol. 5. Australian Forest Development Institute. Alburry, Australia, pp. 1–16. Baddesha, H.S., Chabbra, R., Ghuman, B.S., 1997. Change in soil chemical properties and plant nutrient content under eucalyptus irrigated with sewage water. J. Indian Soc. Soil Sci. 45, 358–362. Baker, A.J.M., 1987. Metal tolerance. New Physiologist 106, 93–111. Bielorai, H.I., Vaismen, Feigin, A., 1984. Drip irrigation of cotton with treated municipal effluents: I. yield response. J. Environ. Quality 13, 231–234. Clarkson, D.T., Luttge, U., 1989. Mineral nutrition: divalent cations, transport and compartmentation. Prog. Botany 51, 93–112. Cromer, R.N., Tompkins, P., Barr, N.J., 1987. Irrigation of Pinus radiata with wastewater: tree growth in response to treatment. Aus. Forest Res. 13, 57–65.
Dillon, P.J., Reid, R.A., Grosbois, E. de, 1987. The rate of acidification of aquatic ecosystem in Ontario, Canada. Nature 329, 45–48. Feigin, A., Vaisman, I., Bielorai, H., 1984. Drip irrigation of cotton with treated municipal effluents: I. Nutrient availability. J. Environ. Quality 13, 234–238. Griepink, B., Mundak, H., Colinet, E., 1984. Heavy metal estimation in industrial and municipal effluent. Ann. Chem. 318, 490–497. Jackson, M.L., 1973. Soil chemical analysis. Prentice Hall of India Private Ltd, New Delhi. Jones Jr., J.B., Case, V.M., 1990. Sampling handling and the analysis of plant tissue samples. In: Westermann, R.L. (Ed.), Soil testing and plan analysis, third ed.. Soil Science Society of America, Madison, WI, pp. 389–427. Lindaman, H.R., 1992. Analysis of Variance in Experimental Design. Springer-Verlag, New York. Macnair, M.R., 1993. Transley review No. 49. The genetic metal tolerance in vascular plants. New Physiologist 124, 541–559. Malkanathi, D.R.R., Mortsugu, M., Yokoyama, K., 1995. Effect of low pH and Al on absorption and translocation of some essential nutrients in excised barley roots. J. Soil Sci. Plant Nutr. 41, 253–262. Mitra, A., Gupta, S.K., 1999. Effect of sewage water irrigation on essential plant nutrient and pollutant element status in vegetable growing area around Calcutta. Indian J. Soc. Soil Sci. 42, 35–69. OMA, 1990. Official Methods of Analysis, 15th ed. Association of Official Analytical Chemists, Arlington, Virginia, USA. Reuss, J.O., Cosby, B.J., Wright, R.F., 1987. Chemical processes governing soil and water acidification. Nature 329, 27–31. Schat, H., Ten Bookum, W.M., 1992. Metal specificity of metal tolerance syndromes in higher plants. In: Proter, J.A., Baker, J.M., Reeves, R.D. (Eds.), The Ecology of Ultramafic (serpentine) oils. Intercept Andover, MA, pp. 337–352. Singh, B., 2001. Effect of water stress and phosphorus application on growth of Dalbergia sissoo. Ph.D. Thesis submitted to Forest Research Institute and Deemed University, Dehradun, India. Stewart, H.T.L., Flinn, D.W., Baldwin, P.J., James, J.M., 1981. Diagnosis and correction of iron deficiency in planted eucalyptus in north west Victoria. Aus. Forest Res. 11, 185–190. Stewart, H.T.L., Hopmans, P., Flinn, D.W., Hilllman, T.J., 1990. Nutrient accumulation in trees and soil following irrigation with municipal effluent in Australia. Environ. Pollut. 63, 155– 177. Swaminathan, K., Vaidheeswaran, P., 1991. Effect of dyeing factory effluent on seed germination and seedling development of groundnut (Arachis hypogea). J. Environ. Biol. 12, 353–358. Willett, I.R., Jakobsen, P., Malafant, K.W.J., Bond, W.J., 1984. Effect of land disposal of lime treated sewage sludge on soil properties and plant growth. Division of water and land resources, CSIRO, Canberra, Div. Rep. 84/3, pp. 56. Woolhouse, H.W., 1983. Toxicity and tolerance in the response of plants to metals. In: Lange, O.L., Nobel, P.S., Osmond, C.B., Ziegler, H. (Eds.), Encyclopedia of Plant Physiology. Physiological plant Ecology. Springer Verlag, Berlin, Germany, pp. 245– 300. Zekri, M., Koo, R.C.J., 1994. Treated municipal wasetwater for citrus irrigation. J. Plant Nutr. 17, 693–708.
Growth and mineral accumulation in Eucalyptus camaldulensis seedlings irrigated with mixed industrial effluents M. Bhati, G. Singh
*
Division of Forest Ecology and Desert Development, Arid Forest Research Institute, New Pali Road, Jodhpur 342005, India Received 21 March 2002; received in revised form 20 September 2002; accepted 1 December 2002
Abstract Effects of mixed industrial effluents on growth, dry matter accumulation and mineral nutrient in Eucalyptus camaldulensis seedlings were studied. The objective was to evaluate the adaptability of E. camaldulensis to effluent, tolerance to excess/deficiency of mineral elements and ultimately to determine suitable combinations of industrial/municipal effluent for their use in biomass production in dry areas. Different irrigation treatments were: T1 : good water; T2 : municipal effluent; T3 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. High concentrations of metal ions and low concentrations of Ca, Mg, K, Na, N and P in soil and seedlings of T4 resulted in mortality of the seedlings within a few days. Addition of the textile/ municipal effluent increased the survival time of the seedlings for two to three months in T6 , T7 and T8 treatments. Among the remaining treatments, the seedlings of T2 attained 131 cm height, 1.97 cm collar diameter, 19 total branches and produced 158 g seedling1 of dry biomass at the age of 10 months. The seedling of T3 produced the least growth and biomass. Growth equivalent to that of the seedlings of T1 treatment was achieved when municipal effluent was mixed with textile effluent (T5 ). There was a decrease in soil pH, EC, SOC, NH4 –N, NO3 –N, PO4 –P and basic cations and increase in the concentration of Cu, Fe, Mn and Zn with T4 treatment. The reverse trend was observed in T3 where a high concentration of Na might have reduced Mg and micronutrient concentration in seedlings potentially affecting root and leaf growth. Mixing of effluents may be useful in tree irrigation to increase biomass productivity, which is evidenced by improved growth in T5 and survival in T6 , T7 and T8 treatments. Further, reduction of toxic concentration of metal ions in effluents may be helpful for a long-term field application. Ó 2002 Elsevier Science Ltd. All rights reserved. Keywords: Arid region; Metal accumulation; Mixed industrial effluents; Tree seedling irrigation; Wastewater quality
1. Introduction Increasing industrialization and urbanization has not only deprived production of crops through land degradation but also remained mute witness to the continuous loss of our precious water resources (Zekri and Koo, 1994). Attempts have been made to reverse the process of this degradation with afforestation with fast growing tree species and disposal of wastewater safely and economically to tree plantations (Bielorai et al., 1984; Feigin et al., 1984). The goal of such endeavours against severe odds is the successful greening of wasteland. The resultant woodland has an appreciable protective action by absorption/uptake of harmful heavy metals from soil
*
Corresponding author. Tel.: +91-0291-742550. E-mail address: [email protected] (G. Singh).
through development of an extensive root system. This reduces the toxicity of the soil and plays an important role to safeguard the environment (Stewart et al., 1990; Cromer et al., 1987). The effluent from different industrial sources has different impacts on the biological system, particularly plants because of different chemical constituents. Mixing of different effluents of different characteristics and their disposal in tree irrigation may be one of the best management options. Eucalyptus camaldulensis was selected for this study because of its important attributes such as tolerance to a wide range of soil type, and pH and rapid growth and high wood yield for timber and fuel wood. It is helpful to recapitulate the soil status and quality (Abo-Hassan et al., 1988). The present investigation was undertaken with the view that mixing of different industrial effluents among each other or with municipal effluent in varying proportions may bring about favorable changes in chemical
0960-8524/03/$ - see front matter Ó 2002 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0960-8524(02)00317-6
222
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
composition. Utilization of mixed effluents may be beneficial for improving soil health and for enhancing growth and biomass production of the tree seedlings. This kind of practice may come up as an alternative forestry/agroforestry-related water technology for irrigation in water and biomass scarce areas. Disposal of effluents to land sometimes results in mortality of plants due to accumulation of metal ions. Therefore, another aspect of this study was to determine the optimum level of application to avoid injury to plants.
2. Methods 2.1. Site description The experiment was conducted at the Arid Forest Research Institute, Jodhpur (72.030 E, 26.450 N). The experiment was done in plastic pots with mean diameters of 35 cm and heights of 55 cm. The soil in each pot was loamy sand (coarse loamy, mixed, hyperthermic family of typic camborthides according to US soil taxonomy) and with a water holding capacity of 9.88% (w/ w) at 0.03 MPa. The soil had 91.5% sand, 7.13% silt and 1.37% clay. Twenty-two kg soil was transferred to each pot and filled up to 50 cm leaving a height of 5 cm for irrigation. Air-dried and sieved soil samples were analyzed for physiochemical properties. Soil nutrient data of July 1999 (before plantation) indicated that this soil was poor in organic carbon (0.13%), NH4 –N (2.17 mg kg1 ), NO3 –N (1.56 mg kg1 ) and PO4 –P (6.00 mg kg1 ). DTPA extractable Mn, Fe, Cu and Zn were 3.30, 2.36, 0.26 and 0.57 mg kg1 . Soil pH and electrical conductivity (EC) in 1:2 soil water suspensions were 7.8 and 0.76 dS m1 , respectively. 2.2. Seedling establishment Six-month old seedlings of E. camaldulensis from a single provenance were planted in August 1999 to provide one seedling per pot. Wastewater application was initiated in September 1999 after proper establishment of the seedlings. Eight treatments were T1 : good water (canal water); T2 : municipal effluent; T3 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. Steel effluent is released after washing of iron sheets using nitric acid, sulphur and hydrofluoric acid in iron rolling mills. Textile effluent is released after washing of excess dyes of printed cloths from the dyeing and printing factories using guar gum (obtained from Cymopsis tetragonoloba), sodium hypochlorite, sodium silicates and detergents. These effluents were obtained from the industries in Jodhpur and municipal effluent from a source point
passing through the experimental field. Samples were collected and brought to the laboratory in resistant plastic bottles to avoid adherence to the container wall. They were stored at 4 °C to minimize microbial decomposition of solids. The experiment was conducted as a complete randomized design with three replications. Seedlings were irrigated to maintain the soil water availability between 80% and 100% of field capacity. Total quantity of effluents added were 63 l in T1 , T2 , T3 and T5 treatments in 27 irrigation events, 2 l in T4 in one irrigation event and 14 l in T6 and T8 in six irrigation events and 19 l in T7 treatments in nine irrigation events. The above variations in quantity and irrigation events were due to seedling mortality after which the irrigation was discontinued in that particular treatment. 2.3. Data collection Height, collar diameter and number of branches were recorded at one month intervals to measure the magnitude of response to different types of industrial/municipal effluents. Plants were harvested when the seedlings of T5 treatment became leafless (i.e., at 10 months of age) for an estimation of biomass production and partitioning. Leaves were separated and the total number of leaves counted and weighed to record fresh weight. Shoots removed from the collar region were measured for shoot length and collar diameter and fresh weights were recorded. Roots along with soil mass were removed from the pots by turning the pots upside down and roots were separated carefully and soil particles adhering to the root surface were removed. Primary and secondary root were measured for length and diameters using tape and vernier caliper. For secondary roots five largest roots were measured and averaged. Numbers of roots were also counted. Fresh weight of root was recorded immediately after measurement. Dry weights of the leaves, shoot and roots were recorded after oven drying of samples for 72 h at 80 °C. Root volume was measured by a water replacement method (Singh, 2001). 2.4. Chemical analysis Irrigation quality criteria, including total solids (TS), total suspended solids (TSS) and other parameters listed in Table 1, of raw municipal effluent, industrial effluents and good water were assessed using standard procedures (APHA, 1975; OMA, 1990). Concentrations of metals were estimated to assess any metals hazards in the effluent (Griepink et al., 1984). Dried leaves, shoot and roots of the seedlings were ground to pass through a 2 mm sieve and digested with triacid mixture (HNO3 : H2 SO4 :HClO4 in 10:4:1 ratio) (Jones and Case, 1990). The N and P contents were determined after wet digestion with 12 ml H2 SO4 using two Kjeltab (Cu/3.5) at
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
223
Table 1 Physico-chemical characteristics of different kinds of effluent QP
T1
T2
T3
T4
T5
T6
T7
T8
pH EC (dS m1 ) TS (mg l1 ) TSS (mg l1 ) TDS (mg l1 ) SAR DO (mg l1 ) BOD (mg l1 ) COD (mg l1 ) K (mg l1 ) Ca (mg l1 ) Mg (mg l1 ) Cl (mg l1 ) Na (mg l1 ) NH4 –N mg l1 NO3 –N mg l1 PO4 –P (mg l1 ) Cu (mg l1 ) Fe (mg l1 ) Mn (mg l1 ) Zn (mg l1 )
7.6 0.20 356 6.7 139 0.08 6.5 2.0 8.0 20 95 49 7.56 4.20 2.1 0.020 0.02 0.003 0.08 0.022 0.017
7.80 0.93 783 156 629.5 0.15 2.20 76.0 190 32 256 156 210 12.50 8.5 0.520 12.30 0.26 3.64 0.32 0.48
9.5 4.30 4100 2000 2800 6.25 12.8 45.0 300 40 28 6 18.46 139.5 0.03 0.001 16.39 Nil Trace Nil Nil
1.4 7.86 8800 7500 5000 0.07 – – 74,830 3 26 7 756 1.50 0.02 0.001 4.23 91 320 280 375
8.4 2.07 1850 500 1350 0.63 8.0 80 290 16 186 98 50.64 42.50 3.2 0.210 13.25 0.06 0.97 0.08 0.21
4.5 5.90 6650 1650 3500 0.08 0.42 20,250 17,800 6 27 10 690 1.75 0.02 0.003 1.24 40.00 100.00 80.00 110.00
4.70 4.90 6500 1560 4940 0.05 0.78 17,250 18,320 8 24 7 675 1.07 0.01 0.002 1.25 35.00 60.00 48.00 75.00
4.60 6.83 5650 1850 3800 0.04 0.50 20,560 25,680 4 25 9 623 0.97 0.01 0.001 1.15 42.00 96.00 78.00 100.25
T1 : good water; T2 : municipal effluent; T4 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. QP: quality parameters; EC: electrical conductivity; TS: total solid; TSS: total suspended solid; TDS: total dissolved solid; SAR: sodium adsorption ratio; DO: dissolved oxygen; BOD: biochemical oxygen demand, and COD: chemical oxygen demand.
350 °C for half an hour, using UV–VIS spectrophotometer (Systronix model 117) at 490 and 420 nm, respectively (Jackson, 1973). Soil pH and EC were determined in 1:2 soil: water ratio. Soil organic matter was determined by the partial oxidation method (Walkey and Black, 1934). Available nitrogen was determined after 2 M KCl extraction using a Tecator Model Enviroflow––5012 autoanalyser. Extractable phosphorus was determined by OlsonÕs extraction method (Jackson, 1973). For determination of macro and micronutrients, soil samples were extracted with 0.1 N HCl and DTPA solution, respectively (Jackson, 1973). Ca, Mg, Cu, Zn, Mn and Fe were estimated in absorption mode and K and Na in emission mode using a Perkin–Elmer (Model3110) double beam atomic absorption spectrophotometer.
2.5. Statistical analysis Data were statistically analyzed using an SPSS package (Lindaman, 1992). Since the experiment was conducted as a complete randomized design, variation over treatments was studied using a one-way ANOVA model with average growth parameters and plant nutrients as dependent variables. Treatments were considered as the fixed effect and within treatment variation as the error.
3. Results 3.1. Effluents characteristics Textile effluent had high pH and EC. Steel effluent and its mixture were acidic in nature but with high EC (Table 1). Dissolved oxygen was almost absent in the steel effluent whereas it was less than 1 mg l1 in the effluents involving steel effluent in different combinations. Municipal effluent exhibited low dissolved oxygen levels when compared with good water. Biochemical oxygen demand (BOD) and chemical oxygen demand (COD) were within the permissible limits except in T4 , T6 , T7 and T8 treatments where they were excessively high (ISI, 1987). TS, TSS and total dissolved solid (TDS) were high in textile effluent, pure steel effluent and mixed effluent (Table 1). Chloride was low in T1 , T2 , T3 and T5 compared to the other treatments. The effluents in T3 , T4 , T6 , T7 and T8 had low Ca and Mg. Metal concentrations were very low in textile effluent, but high in T4 , T6 , T7 and T8 treatments. 3.2. Seedling survival and growth Seedlings of T4 treatment died within two days of steel effluent application. However, the seedlings of T6 , T7 and T8 treatments survived to the age of 2–3 months. Of the eight treatments, seedlings of E. camaldulensis in
224
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
Table 2 Growth of E. camaldulensis seedlings irrigated with different kinds of effluents T T1 T2 T3 T5 P
Initial
10 months
H
CD
NB
H
CD
NB
50 (2.6) 50 (2.5) 51 (2.8) 50 (2.5) >0.05
0.97 (0.03) 0.93 (0.02) 0.87 (0.12) 0.77 (0.12) >0.05
7 (0.1) 11 (2.1) 9 (0.4) 7 (0.1) >0.05
116 (5.8) 131 (4.0) 94 (2.1) 128 (7.8) <0.01
1.87 (0.22) 1.97 (0.03) 1.30 (1.52) 1.47 (0.02) <0.01
9 (1.5) 19 (2.0) 12 (0.3) 11 (0.3) <0.01
T1 : good water; T2 : municipal effluent; T3 : textile effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio. T: treatment; H: height; CD: collar diameter, NB: number of branches. Values are mean of three replication with SEm in parentheses.
T1 , T2 , T3 and T5 treatments survived to the end of the experiment. Initial height, collar diameter and number of branches (September, 1998) did not differ ðP > 0:05Þ among the treatments. However, at the age of 10 months, the seedlings attained 94 cm (T3 ) to 131 cm (T2 ) height (Table 2). Seedlings subjected to T2 treatment had 13% greater height and 5% greater collar diameter than that of T1 treatment. The minimum growth was in T3 among T1 , T2 , T3 and T5 treatments. The increment in T5 over T3 was 36% and 13% for height and collar
diameter. Number of branches was also high ðP < 0:05Þ among the seedlings of different treatments. 3.3. Root growth Number, length, diameter, and volume of primary and secondary root differed significantly ðP < 0:05Þ under the influence of different treatments (Table 3). Seedlings of T2 attained 2.8 times larger root length when compared with T1 treatment. Seedlings of T3
Table 3 Root growth (cm) of 10 months old E. camaldulensis seedlings irrigated with different kinds of effluents Treatment
RL
RD
SR
SL
RV
T1
35 (1.21) 98 (3.51) 29 (4.51) 49 (5.61) <0.01
1.9 (0.02) 2.5 (0.06) 1.0 (0.05) 1.5 (0.03) <0.01
32.00 (2.13) 40.00 (3.52) 31.00 (2.56) 33.00 (3.21) <0.01
33 (0.99) 59 (0.67) 23 (1.85) 42 (1.73) <0.01
87 (2.56) 132 (3.21) 32 (3.56) 60 (3.21) <0.01
T2 T3 T5 P -value
T1 : good water; T2 : municipal effluent; T3 : textile effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio. RL: primary root length; RD: root diameter; SR: number of secondary roots; SL: secondary root length; RV: root volume. Values are mean of three replications with SEm in parentheses.
Table 4 Dry biomass (g seedling1 ) of 10 months old E. camaldulensis seedlings irrigated with different kinds of effluent Treatment
Leaves
Shoot
Root
Total
R/S ratio
Canal water
25 (2.1) 37 (3.2) 13 (4.3) 23 (1.2) <0.01
39 (2.1) 68 (4.6) 27 (2.4) 48 (2.5) <0.01
38 (3.9) 54 (3.4) 14 (1.3) 37 (2.1) <0.01
102 (2.9) 158 (6.6) 54 (1.4) 107 (3.2) <0.01
0.59 (0.004) 0.51 (0.05) 0.35 (0.06) 0.49 (0.02) <0.05
Municipal effluent Textile effluent Textile þ municipal P -value
T1 : canal water; T2 : municipal effluent; T3 : textile effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio. R/S: root biomass to above ground biomass ratio. Values are mean of three replication with SEm in parentheses.
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
treatment had thinner and fewer roots compared to the seedlings of other treatments, which survived for 10 months. Differences in numbers of secondary roots were not significant between the seedlings of T1 , T3 and T5 treatments. Root volume was 52% higher in the seedlings of T2 , whereas it was low in the seedlings of T3 treatment, as compared to that in T1 treatment. 3.4. Biomass T2 treatment resulted in a 1.5 times increase in total dry biomass than that of the seedlings in T1 treatment (Table 4). The increase was 80% in the leaf, 54% in the shoot and 42% in the root. Seedlings of T3 treatment
225
produced the least amount of dry biomass and the reduction was 40% in the leaf, 30% in the shoot and 63% in the root biomass when compared with the seedlings of T1 treatment. However, there was twice the biomass for the seedlings of T5 as compared to that in T3 . The biomass of different plant parts varied significantly among the treatments. Biomass in leaves varied from 21% in T5 to 25% in T1 treatment. Contribution of shoot biomass was high ðP < 0:001Þ in the seedlings of T3 treatment but it was low in T1 treatment. Percent root biomass varied from 26% in the seedlings of T3 treatment to 37% in the seedlings of T1 treatment. Root to shoot ratio was low for the seedlings of T3 treatment and increased up to 0.59 in the seedlings of T1 treatment. Addition of
Table 5 Nutrient composition in different part of E. camaldulensis seedlings irrigated with different effluents Treatment Leaves T1 T2 T3 T4 T5 T6 T7 T8 P -value Roots T1 T2 T3 T4 T5 T6 T7 T8 P -value
N
P
K
Ca
Mg
Na
Cu
Fe
Mn
Zn
20.81 (3.21) 31.56 (5.21) 10.51 (0.32) 2.76 (0.13) 17.89 (1.10) 3.67 (0.11) 3.99 (0.12) 4.16 (0.21)
2.90 (0.11) 4.50 (0.41) 1.09 (0.21) 1.20 (0.11) 1.98 (0.11) 1.40 (0.32) 1.80 (0.21) 2.00 (0.53)
10.78 (1.02) 17.37 (0.56) 8.78 (0.09) 4.78 (1.21) 11.98 (0.12) 4.97 (1.01) 4.99 (1.03) 4.98 (0.98)
11.17 (0.56) 19.78 (0.06) 10.91 (0.05) 6.87 (1.12) 12.89 (0.08) 6.78 (1.62) 6.91 (1.02) 6.79 (2.01)
3.07 (0.08) 5.74 (1.02) 0.60 (0.02) 1.32 (0.12) 2.78 (0.02) 1.41 (0.21) 1.41 (0.35) 1.60 (0.33)
1.46 (0.05) 1.39 (0.31) 2.67 (0.33) 0.70 (0.21) 1.79 (0.05) 0.77 (0.12) 0.77 (0.25) 0.79 (0.21)
16.97 (1.020) 23.67 (1.25) 2.96 (0.52) 48.75 (5.26) 10.97 (2.12) 40.71 (5.23) 40.87 (5.26) 40.30 (6.25)
453.67 (50.12) 781.67 (2.63) 140.51 (2.36) 1710.5 (12.45) 590.71 (23.56) 1251.7 (6.52) 1351.7 (21.65) 1000.5 (52.62)
190.80 (12.05) 390.40 (3.25) 100.71 (3.25) 680.60 (21.56) 110.71 (5.67) 510.70 (5.48) 515.70 (25.64) 507.5 (12.56)
44.67 (10.21) 68.10 (2.03) 21.82 (5.62) 140.67 (20.12) 41.67 (6.23) 110.70 (7.45) 100.71 (8.56) 110.71 (10.25)
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
6.47 (1.61) 8.67 (2.52) 3.46 (2.13) 1.56 (0.52) 6.16 (2.10) 1.45 (0.22) 1.58 (0.53) 1.60 (0.22)
0.99 (0.22) 1.10 (0.21) 0.40 (0.10) 0.61 (0.12) 0.67 (0.11) 0.60 (0.12) 0.62 (0.21) 0.62 (0.11)
4.35 (0.01) 5.68 (0.02) 1.41 (0.05) 0.73 (0.03) 4.49 (0.15) 0.70 (0.06) 0.70 (0.06) 0.72 (0.15)
3.89 (0.05) 5.09 (0.05) 1.92 (0.06) 1.72 (0.21) 3.99 (0.36) 1.87 (0.13) 1.87 (0.13) 1.89 (0.25)
2.01 (0.03) 1.97 (0.31) 0.27 (0.06) 0.87 (0.12) 0.99 (0.13) 0.91 (0.20) 0.91 (0.11) 0.99 (0.12)
0.83 (0.02) 0.51 (0.05) 0.99 (0.12) 0.42 (0.08) 0.89 (0.15) 0.52 (0.05) 0.55 (0.15) 0.50 (0.16)
5.79 (1.00) 9.71 (1.25) 1.39 (0.52) 32.06 (2.23) 5.89 (0.36) 27.89 (5.26) 29.67 (6.25) 28.78 (2.45)
140.81 (5.62) 267.10 (3.21) 42.15 (3.12) 806.70 (10.25) 141.67 (0.65) 716.70 (6.52) 678.70 (8.74) 609.70 (10.25)
120.71 (10.25) 185.10 (2.12) 32.68 (5.21) 303.67 (2.65) 110.72 (2.56) 295.40 (12.56) 280.15 (6.52) 281.50 (10.45)
28.76 (2.56) 31.53 (2.65) 6.79 (1.21) 92.71 (10.23) 19.79 (2.31) 87.58 (6.48) 85.86 (10.23) 88.71 (7.54)
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
T1 : good water; T2 : municipal effluent; T3 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. Values are mean of three replications with SEm in parentheses. N, P, K, Ca, Mg, Na are in g kg1 and Cu, Fe, Mn, Zn are in mg kg1 .
226
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
municipal effluent to textile effluent (T5 ) increased the root/shoot ratio to 0.49.
ment. However, the soil of T4 , T6 , T7 and T8 exhibited a drastic reduction in soil pH and EC. A two-fold increase in SOC was observed in the soil of T2 treatment whereas it decreased by 31% in T3 treatment. SOC was reduced drastically to 54% in T4 and 31% in soil of T7 treatment. NH4 –N and NO3 –N did not differ in soil of T1 , T2 and T5 treatments but were high ðP < 0:05Þ as compared to their initial concentrations (Table 6). Soil of T4 , T6 , T7 and T8 treatment had approximately 50% lower NH4 –N and NO3 –N when compared with that of T1 , T2 , T3 and T5 treatments. Increase in the PO4 –P concentration occurred more in soil of T3 treatment, whereas the soil of T4 , T6 , T7 and T8 treatment were almost similar in their concentrations. PO4 –P concentration was significantly lower in the soil of T1 treatment. Concentration of Na, Ca and Mg did not differ between T2 and T1 treatment but K increased by 70%. In soil of T5 treatment, Na increased by 30% and K by 84% over the initial concentration whereas Ca and Mg did not differ. However, the soil from T4 , T6 , T7 and T8 treatments displayed significantly low K, Ca and Mg concentrations. DTPA extractable Cu, Fe, Mn and Zn increased with continuous addition of effluent as compared to good water irrigation. T3 was the only treatment, the soil of which had low micronutrients concentration. The increase in Cu in soil of T2 and T5 treatment was approximately 4.9 and 3.9 fold, respectively, whereas it increased considerably in the soil of T4 , T6 , T7 and T8 treatments when compared to its initial concentration. Fe concentration increased from 4.9 fold in T2 to 60.0 fold in T4 treatment. Mn concentration in the soil of T2
3.5. Plant mineral composition Mineral element concentrations in seedlings differed significantly ðP < 0:01Þ both due to the seedling parts and treatments (Table 5). Leaves had the highest concentration of nutrients followed by shoot and roots in all the eight treatments under study. N, P, K, Ca and Mg concentrations were high in the seedlings of T2 followed by T1 except in root in which Mg concentration was high in the seedlings of T1 . Concentrations of Cu, Zn, Mn and Fe were drastically high in the seedlings of T4 , T6 , T7 and T8 , which received steel effluent and its combination. Concentration of N, P, K and Ca was low in these treatments. Concentration of Na was significantly high in the seedlings of T3 . It was reduced to its lowest value in T4 treatment. The trend of Mg was reverse to that of Na in the seedlings of T3 treatment. Seedlings of T2 treatment had high concentration of these mineral elements except Na among the surviving treatments (T1 , T2 , T3 and T5 ). 3.6. Soil properties Effluent irrigated soil had high (P < 0:01) pH, EC, soil organic carbon (SOC), NH4 –N, NO3 –N, PO4 –P, Cu, Fe, Mn and Zn as compared to good water irrigated soil. Increase in pH was 1.3 unit and EC by 7 times in soil of T3 treatment compared to the soil of T1 treat-
Table 6 Changes in soil properties under the influence of different kind of effluent application planted with E. camaldulensis seedlings Treatment
pH
Initial
7.60 0.65 0.13 (0.03) (0.05) (0.005) 7.60 0.67 0.13 (0.02) (0.03) (0.02) 7.90 0.67 0.23 (0.02) (0.03) (0.06) 8.86 3.82 0.09 (0.02) (0.06) (0.006) 4.50 0.25 0.04 (0.03) (0.02) (0.01) 7.92 1.92 0.12 (0.02) (0.05) (0.006) 4.90 0.25 0.09 (0.02) (0.03) (0.006) 4.80 0.26 0.10 (0.04) (0.03) (0.01) 5.20 0.26 0.09 (0.04) (0.03) (0.006) <0.01 <0.01 <0.01
T1 T2 T3 T4 T5 T6 T7 T8 P -value
EC
SOC (%)
NH4 –N
NO3 –N
PO4 –P
K
Ca
Mg
6.00 (0.07) 6.00 (0.07) 6.23 (0.04) 4.14 (0.08) 2.80 (0.07) 5.97 (0.05) 2.86 (0.03) 3.13 (0.06) 3.01 (0.03) <0.01
1.40 (0.03) 1.40 (0.04) 1.50 (0.03) 1.61 (0.04) 0.65 (0.02) 1.41 (0.04) 0.67 (0.03) 0.69 (0.02) 0.61 (0.02) <0.01
5.00 (0.09) 5.00 (0.12) 10.80 (0.17) 12.50 (0.32) 4.20 (0.13) 11.40 (0.23) 5.00 (0.10) 5.00 (0.10) 5.50 (0.08) <0.01
0.08 (0.004) 0.08 (0.005) 0.13 (0.002) 0.20 (0.011) 0.06 (0.003) 0.14 (0.004) 0.06 (0.002) 0.07 (0.005) 0.06 (0.002) <0.01
10.75 (0.18) 10.39 (0.26) 11.17 (0.15) 8.64 (0.23) 6.32 (0.20) 10.09 (0.12) 6.34 (0.13) 6.46 (0.14) 6.40 (0.06) <0.01
0.25 0.97 (0.013) (0.07) 0.25 0.89 (0.019) (0.06) 0.27 0.97 (0.006) (0.05) 0.19 2.55 (0.009) (0.04) 0.15 0.19 (0.005) (0.02) 0.25 1.26 (0.021) (0.04) 0.16 0.13 (0.008) (0.04) 0.17 0.14 (0.004) (0.03) 0.15 0.14 (0.005) (0.02) <0.01 <0.01
Na
Cu 0.26 (0.01) 0.26 (0.01) 1.26 (0.07) 0.16 (0.03) 45.62 (1.67) 1.01 (0.05) 45.91 (1.61) 37.27 (0.93) 38.90 (1.79) <0.01
Fe
Mn
2.36 3.30 (0.06) (0.11) 2.30 3.00 (0.07) (0.10) 11.53 10.00 (0.68) (0.38) 2.23 3.20 (0.05) (0.07) 190.60 135.50 (7.39) (3.17) 5.60 7.87 (0.40) (0.12) 127.84 145.35 (5.36) (3.26) 123.53 94.95 (11.76) (2.41) 168.90 155.30 (6.30) (3.42) <0.01 <0.01
Zn 0.57 (0.04) 0.51 (0.03) 1.82 (0.05) 0.50 (0.02) 90.52 (2.86) 1.72 (0.02) 46.78 (1.32) 32.15 (2.33) 45.70 (1.74) <0.01
T1 : good water; T2 : municipal effluent; T3 : textile effluent; T4 : steel effluent; T5 : textile effluent þ municipal effluent in 1:1 ratio; T6 : steel effluent þ municipal effluent in 1:2 ratio; T7 : steel þ textile þ municipal effluent in 1:2:2 ratio; and T8 : steel þ textile effluent in 1:2 ratio. Values are mean of three replication with SEm in parentheses. EC is in dS m1 ; K, Ca, Mg and Na are in g kg1 and the rest are in mg kg1 .
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
and T5 treatments increased by 2.4 fold whereas the increase was 41.0 fold in T4 and 16.5 fold in the soils of T6 , T7 and T8 treatments. Zn accumulation was almost three fold in the soils of T2 and T5 treatments when compared to the soil of T1 treatment. The increase was very high in the soil of T4 , T6 , T7 and T8 treatments. Increase in concentrations of these micronutrients in soil of T1 treatment was also observed compared to their initial concentrations.
4. Discussion Immediate mortality in the seedlings under exogenously supplied steel effluent was probably due to heavy metals toxicity. It is evident by the high concentration of Cu, Fe, Mn and Zn observed in plants and soil. This is in agreement with the finding that high concentration of metals is toxic to plants (Woolhouse, 1983; Baker, 1987; Macnair, 1993). High metal concentration affects mobilization and balanced distribution of essential elements among different plant parts via competitive uptake (Clarkson and Luttge, 1989; Schat and Ten Bookum, 1992). It results in mortality of the seedlings. Survival extension of the seedling in T6 , T7 and T8 treatments up to two to three months may be due to decreased loading of heavy metal and addition of major essential plant nutrients through the mixing of the textile and municipal effluent. Marked difference in growth and biomass production under different kinds of effluent application may be due to variations in chemical constituents, particularly metal ions. Restricted growth by the seedlings irrigated with pure textile effluent (T3 ) was attributed to high sodium concentration as evidenced by high value of SAR and low concentration of bivalent Ca and Mg in this effluent. It may partly also be due to high TS, TSS and TDS which might have affected the osmotic relations of the seedlings (Swaminathan and Vaidheeswaran, 1991). The enhanced salinity and conductivity of the solutes might have caused Mg deficiency as evidenced by low Mg in plant parts, though the concentration of micronutrients was also low. Mixing of the municipal effluent in the textile effluent resulted in stimulation of growth and biomass production. This suggests that the toxic effect of textile effluent may be reduced by mixing of municipal effluent and addition of mineral elements particularly Mg and micronutrients. It might have also made some favourable changes in soil plant water matrix. Greater growth and biomass production of the seedlings of T2 treatment may be due to sufficient availability of water and essential elements. High leaf biomass in the seedlings of T2 treatment is obviously due to addition of nitrogen and phosphorus through municipal effluent addition. However, higher proportion of biomass in shoot in the seedlings of T3 treatment is
227
probably due to decreased leaf and root biomass. The discrepancy in nutrient concentration and uptake in E. camaldulensis may arise due to water and nutrient supply. Higher concentration of Cu, Fe, Mn and Zn and low concentration of Na, K, Ca, Mg, N and P in perennial parts of the seedlings irrigated with steel effluent and the allied mixtures might be due to low pH, increasing solubility of metals ions resulting in excess metal affecting absorption and translocation of basic cations (Malkanathi et al., 1995). Low concentration of Cu, Zn, Mn, Fe, Ca, Mg and K in the seedlings of T3 treatment was probably due to low availability of these ions in textile effluent (Table 1). Perhaps, high concentration of Na ion showed complementary competition for absorption of these ions under increased soil salinity and decreased water availability. Significant decrease in SOC in T4 , T6 , T7 and T8 was believed to be due to loss of organic acids of humic origin from the soil (Dillon et al., 1987). Decreased availability of Ca, Mg, K and Na may be due to leaching losses of these ions in low pH (Reuss et al., 1987). Greater increases in pH under T3 was due to the alkaline nature of textile effluent with high concentrations of Na (Willett et al., 1984). The decrease in micronutrient concentration was due to increase in soil alkalinity and/ or their less availability in textile effluent. With increased alkalinity, Na might induce the deficiency of Cu, Fe, Mn, Zn, Ca and Mg as observed by seedling nutrient analysis. Deficiency of Cu, Mn, Fe and Zn has also been observed in Eucalyptus planted in calcareous soil irrigated with effluent of high pH (Stewart et al., 1981). It is also supported by the less growth and low nutrient uptake in response to this treatment. Improvement in soil of T5 treatment might be due to addition of municipal effluent as shown by increased availability of micronutrient and Mg in soil and seedlings of T5 treatment. Increased soil availability of PO4 –P, K, Ca, Cu, Fe, Mn and Zn in T2 might be due to their addition through municipal effluent in spite of their high uptake by the growing plants. The study of Mitra and Gupta (1999) on nutrients and heavy metal status indicated that Cu, Fe, Mn and Zn increased with increase in quantity of municipal effluent irrigation. Baddesha et al. (1997) have also reported that irrigation of soil under Eucalyptus plantation with sewage water increased the macro and micronutrient concentration. The result of the present study demonstrated that concentration of Na was less in sewage-irrigated soil compared to good water. 4.1. Conclusion and recommendation The study suggests that steel effluent was toxic to the seedlings because of high concentration of metal ions, which accumulated in soil and seedling parts. Low pH influenced the metal mobilization as evidenced by high concentration of the metal ions and reciprocally low
228
M. Bhati, G. Singh / Bioresource Technology 88 (2003) 221–228
concentration of basic cations, N and P in seedlings. Combinations of steel effluent also exhibited a lethal effect, but seedling survival up to 3 months is indicative of favourable changes in chemical composition after addition of textile and municipal effluents. Pure textile effluent affected the root and leaf growth adversely, which may be because of Na-induced Mg and micronutrients deficiency. Addition of municipal effluent to textile effluent improved the growth, biomass and nutritional status of E. camaldulensis seedlings. It is recommended as one of the better options for utilization of textile industrial effluent in tree growing. Seedlings irrigated with municipal effluent showed optimum growth and plant nutrient concentration. It may be used as an optimal strategy for raising woodlot to supply fuel wood in vicinity of a suburban area. However, reduction of toxic concentration of metal ions in effluents may be helpful for their long-term field application. Acknowledgements Authors are thankful to the Director Arid Forest Research Institute, Jodhpur for providing research facilities. One of us (MB) thanks ICFRE, Dehradun for the award of JRF/SRF. References APHA, AWWA, WPCF, 1975. Standard method for the examination of water and wastewater, 14th edn. American Public Health Association, Washington, USA. Abo-Hassan, A., Kandeel, S.A., Kherallah, I.E., 1988. New eucalypt species introduction in the Saudi Arabia central zone. In: Proceedings of the International Forestry Conference, Australian Bicentenary, vol. 5. Australian Forest Development Institute. Alburry, Australia, pp. 1–16. Baddesha, H.S., Chabbra, R., Ghuman, B.S., 1997. Change in soil chemical properties and plant nutrient content under eucalyptus irrigated with sewage water. J. Indian Soc. Soil Sci. 45, 358–362. Baker, A.J.M., 1987. Metal tolerance. New Physiologist 106, 93–111. Bielorai, H.I., Vaismen, Feigin, A., 1984. Drip irrigation of cotton with treated municipal effluents: I. yield response. J. Environ. Quality 13, 231–234. Clarkson, D.T., Luttge, U., 1989. Mineral nutrition: divalent cations, transport and compartmentation. Prog. Botany 51, 93–112. Cromer, R.N., Tompkins, P., Barr, N.J., 1987. Irrigation of Pinus radiata with wastewater: tree growth in response to treatment. Aus. Forest Res. 13, 57–65.
Dillon, P.J., Reid, R.A., Grosbois, E. de, 1987. The rate of acidification of aquatic ecosystem in Ontario, Canada. Nature 329, 45–48. Feigin, A., Vaisman, I., Bielorai, H., 1984. Drip irrigation of cotton with treated municipal effluents: I. Nutrient availability. J. Environ. Quality 13, 234–238. Griepink, B., Mundak, H., Colinet, E., 1984. Heavy metal estimation in industrial and municipal effluent. Ann. Chem. 318, 490–497. Jackson, M.L., 1973. Soil chemical analysis. Prentice Hall of India Private Ltd, New Delhi. Jones Jr., J.B., Case, V.M., 1990. Sampling handling and the analysis of plant tissue samples. In: Westermann, R.L. (Ed.), Soil testing and plan analysis, third ed.. Soil Science Society of America, Madison, WI, pp. 389–427. Lindaman, H.R., 1992. Analysis of Variance in Experimental Design. Springer-Verlag, New York. Macnair, M.R., 1993. Transley review No. 49. The genetic metal tolerance in vascular plants. New Physiologist 124, 541–559. Malkanathi, D.R.R., Mortsugu, M., Yokoyama, K., 1995. Effect of low pH and Al on absorption and translocation of some essential nutrients in excised barley roots. J. Soil Sci. Plant Nutr. 41, 253–262. Mitra, A., Gupta, S.K., 1999. Effect of sewage water irrigation on essential plant nutrient and pollutant element status in vegetable growing area around Calcutta. Indian J. Soc. Soil Sci. 42, 35–69. OMA, 1990. Official Methods of Analysis, 15th ed. Association of Official Analytical Chemists, Arlington, Virginia, USA. Reuss, J.O., Cosby, B.J., Wright, R.F., 1987. Chemical processes governing soil and water acidification. Nature 329, 27–31. Schat, H., Ten Bookum, W.M., 1992. Metal specificity of metal tolerance syndromes in higher plants. In: Proter, J.A., Baker, J.M., Reeves, R.D. (Eds.), The Ecology of Ultramafic (serpentine) oils. Intercept Andover, MA, pp. 337–352. Singh, B., 2001. Effect of water stress and phosphorus application on growth of Dalbergia sissoo. Ph.D. Thesis submitted to Forest Research Institute and Deemed University, Dehradun, India. Stewart, H.T.L., Flinn, D.W., Baldwin, P.J., James, J.M., 1981. Diagnosis and correction of iron deficiency in planted eucalyptus in north west Victoria. Aus. Forest Res. 11, 185–190. Stewart, H.T.L., Hopmans, P., Flinn, D.W., Hilllman, T.J., 1990. Nutrient accumulation in trees and soil following irrigation with municipal effluent in Australia. Environ. Pollut. 63, 155– 177. Swaminathan, K., Vaidheeswaran, P., 1991. Effect of dyeing factory effluent on seed germination and seedling development of groundnut (Arachis hypogea). J. Environ. Biol. 12, 353–358. Willett, I.R., Jakobsen, P., Malafant, K.W.J., Bond, W.J., 1984. Effect of land disposal of lime treated sewage sludge on soil properties and plant growth. Division of water and land resources, CSIRO, Canberra, Div. Rep. 84/3, pp. 56. Woolhouse, H.W., 1983. Toxicity and tolerance in the response of plants to metals. In: Lange, O.L., Nobel, P.S., Osmond, C.B., Ziegler, H. (Eds.), Encyclopedia of Plant Physiology. Physiological plant Ecology. Springer Verlag, Berlin, Germany, pp. 245– 300. Zekri, M., Koo, R.C.J., 1994. Treated municipal wasetwater for citrus irrigation. J. Plant Nutr. 17, 693–708.