Journal of Tropical Forest Science 11(2) :345-355 (1999)
EFFECT OF MULCHES ON NUTRIENT UPTAKE OF ALBIZIA
PROCERA AND SUBSEQUENT NUTRIENT ENRICHMENT OF COAL MINE OVERBURDEN
A. K. Singh & R. B. Singh
Tropical Forest Research Institute, P.O. - RFRC, Mandla Road, Jabalpur, 482021 M.P., India Received December 1995
SINGH, A. K. & SINGH, R. B. 1999. Effect of mulches on nutrient uptake of Albizia procera and subsequent nutrient enrichment of coal mine overburden. Nutrient concentration and accumulation of Albizia procera grown for one year in pots under the influence of different mulches (control, stones/gravels, husks, leaf litter and grasses) were studied and subsequent nutrient enrichment of the soils was estimated. The substrate used for growing Albizia procera as test crop was a mixture of coal mine overburden and compost in 1:1 proportion (V/V). Against increases of biomass by
128.6, 116.8, 113.8 and 79.9% over the control due to application of husks, leaf litter, grasses and stones/gravels respectively, there were increases of 317.2, 210.9,198.5 and 123.1% in total accumulation of nutrients, which constituted 4.83, 3.80, 3.69 and 3.28% of the total biomass. The total nutrient content of the control (1.79 g plant-1) contributed only 2.65% to the total biomass. Appreciable increases in available nutrient status (N, P & K), CEC and exchangeable cations in the soils were also observed due to application of mulches with the maximum value given by husk mulch followed by grasses, leaf-litter and stones/gravels. These mulches should be used in afforesting mine overburdens for better growth, biomass production and nutrient uptake.
Key words: Responses - mulch - nutrient - uptake - Albizia procera - coal mine overburden - enrichment - matrix
SINGH, A. K.& SINGH, R.B. 1999. Kesan sungkupan terhadap pengambilan nutrien Albizia procera dan pengayaan nutrien berikutnya bagi beban atas lombong arang batu.
Kepekatan nutrien dan penimbunan Albizia procera yang ditanam selama satu tahun di dalam tabung dengan pengaruh sungkupan yang berbeza (kawalan, batu/kerikil, sekam, sarap daun dan rumput) dikaji dan pengayaan nutrien tanah berikutnya dianggarkan. Substrat yang digunakan untuk menanam Albizia procera sebagai tanaman ujian ialah campuran beban atas lombong arang batu dan kompos dalam nisbah 1:1 (V/V). Bertentangan dengan pertambahan biojisim masing-masing sebanyak 128.6,116.8,113.8 dan 79.9 % melebihi kawalan akibat penggunaan sekam, sarap daun, rumput dan batu/kerikil, terdapat tambahan sebanyak 317.2, 210.9, 198.5 dan 123.1% dalam jumlah penimbunan nutrien, menjadikannya 4.83, 3.80, 3.69 dan 3.28% daripada jumlah biojisim. Jumlah kandungan nutrien bagi kawalan (1.79 g setiap tumbuhan) menyumbangkan hanya 2.65 % kepada jumlah biojisim.
Pertambahan yang ketara dalam status nutrien tersedia (N,P, & K), CEC dan kation boleh tukar dalam tanah juga dicerap akibat penggunaan sungkupan ini dengan nilai maksimum yang diberikan oleh sungkupan sekam, diikuti dengan sungkupan rumput, sungkupan sarap-daun dan sungkupan batu/kerikil. Sungkupan-sungkupan ini sepatutnya digunakan untuk menghutankan beban atas lombong bagi pertumbuhan, pengeluaran biojisim dan pengambilan nutrien yang lebih baik.
345
Introduction
Success of afforestation/revegetation of mine overburdens depends on several factors and their combinations primarily due to the refractory nature of the matrix. The non-existence of organic matter, deficiency of nutrients and moisture holding capacity of the matrix make it less productive than most soils. Moisture and thermal stress on such overburden sandy materials seriously affect the availability and absorption of water by roots, microbial activity and the availability of nutrients and subsequent growth and yield of plants ( Gupta & Aggarwal 1988).
For better survival, growth and biomass production, use of amendments serve as a booster. Mulching has been found to be effective to a considerable extent in lowering soil temperature in the root zone (Prihar et al. 1979) as well as conserving moisture and checking evaporation (Chaudhary & Prihar 1974, Gupta & Gupta 1983, Gupta & Aggarwal 1988, Marshall & Holmes 1988, Singh et al 1989). Growth and biomass production of Albizia procera have been found to be considerably increased by the use of different mulches in coal (Singh et al. 1994a) and copper (Singh et al. 1995) mine overburdens as well as skeletal soil (Singh et al. 1994b).
In addition to conserving soil moisture and reducing thermal stress, mulching materials like leaf litter, grasses and husks may also contribute to the status of nutrients and consequent soil enrichment leading to increased growth and bio- mass production. Nutrient uptake may also be higher in the plants treated with mulches, but unfortunately no information is available. In view of the above a pot experiment was conducted with coal mine overburden using stones/gravels, husks, leaf litter and grasses as mulches to see their effect on nutrient uptake of Albizia procera and subsequent soil enrichment.
Materials and methods
Coal mine overburden sample was collected from Bishrampur, Madhya Pradesh (23° 11' N, 82° 58 'E) and analysed as per standard procedures (Piper 1950, Subbiah
& Asija 1956, Jackson 1973) for its physico-chemical properties (Table 1). The dump matrix was mixed with compost (analysis given in Table 1) in 1:1 proportion
(v/v). Earthen pots were filled with the mixture (10 kg pot-1) and five seeds (24 hours water soaked) of A. procera were sown in each pot on 5 February 1993.
After seedling establishment, all except one healthy seedling were removed.
When seedlings had attained a height of approximately 5 to 6 cm, mulches (stones/gravels, husks, leaf litter and grasses) were applied and a control was left as such without any mulch. Individual treatment consisted of five pots replicated five times. The experiment was laid out in a randomised block design and was terminated one year after seed sowing, when plants were uprooted. Roots, branches + twigs and leaves of all plants uprooted were separated from their respective leading shoots (stems), weighed separately and oven dried (80 °C).
Sampled plant parts were crushed to powder for chemical analysis. Individual
plant part samples of one replication were mixed together to form a composite
sample. Thus there were five replicates of every plant part of one treatment. SoilJournal of Tropical Forest Science. 11 (2):345-355 (1999) 347
samples were also collected from each treatment/replication after termination of the experiment and analysed for different soil attributes by standard procedures (Piper 1950, Subbiah & Asija 1956, Jackson 1973). CEC and exchangeable cations were estimated using NH4OAc as extractant with hydroxylamine hydrochloride as buffering agent. Samples of plant parts were digested in ternary acid mixture (H2SO4: HCLO4:HNO3: 10:1:4). Nitrogen in plant parts was estimated directly by Kjeltec (Model No. 1030), phosphorus by the vanado-molybdo-phosphoric acid method (Jackson 1973), potassium by flame photometry and calcium and magnesium by the versene titration method (Jackson 1973).
Table 1. Physico-chemical properties of original coal mine overburden matrix and compost
Physico-chemical attributes
Sand % Silt % Clay %
Available nutrients ( p p m ) N
PA
K2OCoal m i n e overburden
69.5 24.0 6.5
92.8 5.2 - 324.8
Compost
-
Total n u t r i e n t s (%) 0.65 0.28 1.01 Exchangeable cations [cmole kg-1]
Ca2+ - 1.5
Mg2+ - 0.6
Results and discussion
The effectiveness of different mulches on growth and biomass production of A. procera in coal mine overburden has already been discussed in an earlier communication (Singh et al. 1994a). Nutrient concentration in different plant parts, total uptake of major nutrients and soil enrichment as influenced by mulching will be discussed in the present paper.
Concentrations of nutrients in different plant parts varied considerably (Table 2). Nitrogen was the major constituent among the nutrients with the highest concentrations in all plant parts. This was followed by potassium, calcium, magnesium and phosphorus. With the exceptions of nitrogen, phosphorus and calcium concentrations in leaves; phosphorus and calcium in branches and twigs;
magnesium in stems; and phosphorus, potassium and magnesium concentrations in roots; there were no significant differences (p<0.01) in nutrient concentrations in plants treated with leaf litter from their respective counterparts in the plants treated with grass mulches. Mulching-induced increases in nitrogen concentration over the control in branches and twigs, stems and roots were lower than those in leaves. Slightly higher values of nutrient concentration and accumulation of nutrients (significant at p < 0.05) in the plants treated with leaf litter as compared
to grass mulches could be due to the slightly higher biomass production. Apart from nitrogen in leaves under leaf litter (3.31%), the highest concentrations of nutrients invariably occurred in all plant parts under the husk mulch and the lowest in the control followed by stones/gravels. Concentration of phosphorus exhibited a decreasing trend from leaves to branches + twigs and stems with a slight increase in roots in the presence of husks, leaf litter and grasses. Branches and twigs, stems and roots had the same phosphorus concentration (0.028%), while leaves had less (0.023%) when the plants were treated with stones/gravels.
Table 2. Nutrient concentrations in different plant parts of Albizia procera grown in coal mine overburden under the influence of mulches
Mulch
Control Stones/gravels Husk
Leaf litter Grasses CD 5%
CD 1%
Control Stones/gravels Husk Leaf litter Grasses CD 5%
CD 1%
Nutrient concentration (%) (Oven dry basis) N
2.08 2.53 (21.6) 3.05 (46.6) 3.31 (59.1) 2.83 (36.0) 0.029 0.040
1.30 1.37 (5.4) 1.65 (26.9) 1.56 (20.0) 1.64 (26.1) 0.0379 0.0522
P
0.018 0.023 (27.7) 0.047 (161.7) 0.39
(116.7) 0.036 (100.0) 0.0010 0.0013
0.023 0.028 (21.7) 0.042
(82.6) 0.037 (60.8) 0.033 (43.4 ) 0.0029 0.0040
K Leaves
0.50 0.70 (40.0) 0.90 (80.0) 0.80 (60.0) 0.80 (60.0) 0.0245 0.0338 Branches & Twigs
0.60 0.70 (16.7) 0.83 (38.3) 0.82 (36.7) 0.85 (41.7) 0.0256 0.0353
Ca
0.46 0.54 (17.4) 0.80 (73.9) 0.60 (30.4) 0.72 (56.5) 0.169 0.0234
0.32 0.36 (12.5) 0.54 (68.8) 0.40 (25.0) 0.48 (50.0) 0.0281 0.0387
Mg
0.15 0.15 (0) 0.19 (26.7) 0.16 (6.7) 0.17 (13.3) 0.0236 0.0325
0.12 0.12 (0) 0.19 (58.3) 0.15 (25.0) 0.16 (33.3) 0.0200 0.0270 Stems
Control Stones/gravels Husk Leaf litter Grasses CD 5%
CD1%
1.33 1.49 (12.0) 1.72 (29.3)
1.65 (24.0) 1.57 (18.0) 0.059 0.082
0.023 0.028 (21.7) 0.041
(78.3) 0.033
(43.5) 0.033
(42.5) 0.0016 0.0022
0.52 0.60 (15.4) 0.76 (46.2) 0.68 (30.8) 0.68 (30.8) 0.0129 0.0180
0.23 0.32 (39.1) 0.42 (82.6) 0.34 (47.8) 0.36 (56.5) 0.019 0.026
0.12 0.19 (58.3) 0.20 (66.7) 0.19 (58.3) 0.15 (25.0) 0.037 0.057
(continued)
Journal of Tropical Forest Science ll(2):345-355 (1999) 349
Table 2 (Continued)
Control Stones/gravels Husk
Leaf litter Grasses CD 5%
CD 1%
1.41 1.44 (2.1) 1.93 (36.9) 1.85 (31.2) 1.84 (30.5) 0.207 0.285
0.028 0.028 (0) 0.044 (57.1)
0.035
(25.0) 0.038 (35.7) 0.001 0.0014
Roots 0.40 (50.0) 0.80 (100.0) 0.70 (75.0) 0.80 (100.0) 0.0104 0.0143
0.28 0.54 (92.9) 0.62 (121.4) 0.44 (57.1) 0.44 (57.1) 0.0198 0.0273
0.10 0.15 (50.0) 0.17 (70.0) 0.19
(90.0) 0.15 (50.0) 0.0489 0.0674
Note: Figures in parentheses show percentage increases over control.
Potassium concentration has been found to be somewhat higher than that of calcium in plant parts due to its higher status in the substrate. Further, the presence of calcium in sufficient quantities in roots stimulates K uptake by controlling the influx and efflux of K through the root plasma membrane (Marschner 1990).
Magnesium concentration and its total uptake are very low as compared to other cations due to its low affinity for binding sites in root plasma membrane as well as competition by other cations like calcium and potassium (Marschner 1990).
Non-significant (p<0.01) differences in the values of magnesium concentration in the majority of plant parts in the treatments receiving husk, leaf litter and grass mulches indicate the similarity in effectiveness of those mulches, particularly for the uptake of this nutrient. However, significant differences in total accumulation of this nutrient by plant parts under the three mulches were due to variations in biomass production, which is a cumulative effect of environmental factors and uptake of other nutrients.
Uptake and accumulation of nutrients in different plant parts follow the trend of biomass production which was greatly influenced by the application of mulches (Table 3). The maximum accumulation of all nutrients in component and total biomass occurred under the influence of husk mulch and the minimum under stones/gravels in comparison with the control. Except for nitrogen in leaves and magnesium in stems, other nutrients exhibited almost similar values in above- ground parts in plants treated with grass mulch as with leaf litter. Calcium and phosphorus are released slowly from decomposing forest leaf litter (Attiwill 1968, Upadhyay 1982) and retained within the litter until the major breakdown of the cell wall tissues (Burges 1956). The results show that Ca was probably retained longer in leaf litter resulting in its lower status in the substrate and consequently
lower uptake in plants treated with leaf litter. This was also confirmed from the
data of soil analysis (Table 4). Owing to the higher root biomass production in leaf litter treated plants, accumulation of nutrients in roots of the latter (total nutrient content per plant) was higher than in roots of those plants treated with grass mulches (Table 3). Husk mulch proved to be the most effective in this respect with almost two-fold nutrient accumulation to that of stones and gravels.
Table 3. Nutrient accumulation in different plant parts of Albizia procera grown in coal mine overburden under the influence of mulches Mulch
Control Stones/
gravels Husk Leaf litter Grasses CD 5%
CD 1%
Oven dry biomass (g plant-1)
28.8 58.0 (101.4) 78.8 (173.6) 55.6
(93.06) 59.0 (104.9)
Nutrient content (g plant-1) N
0.599 1.467 (144.9) 2.403 (301.2) 1.840 (207.2) 1.669 (178.6) 0.034 0.047
P
0.005 0.013 (155.7) 0.037
(611.5) 0.022 (323.1) 0.021
(303.8) 0.004 0.005
K Leaves
0.144 0.406 (181.9) 0.709 (392.4) 0.445
(209.0) 0.472
(227.8) 0.004 0.005
Ca
0.132 0.313 (137.1) 0.630 (377.3) 0.334 (153.0) 0.425
(220.0) 0.005 0.007
Mg
0.043 0.087 (102.3) 0.149 (246.5) 0.089 (107.0) 0.100 (132.6) 0.003 0.004
Total
0.923 2.286 (147.7) 3.928 (325.6) 2.730 (195.8) 2.687 (191.1) 0.0286 0.0395
% of biomass
3.20 3.94 4.98 4.91 4.55
Branches & Twigs Control
Stones/
gravels Husk Leaf litter- Grasses CD 5%
CD 1%
Control Stones/
gravels Husk Leaf l i t t e r Grasses CD 5%
CD 1%
Control Stones/
gravels Husk Leaf l i t t e r
6.4 9.0 (40.6) 16.6 (159.4) 11.8 (84.4) 11.4 (78.1)
9.4 17.6 (87.2) 28.6 (204.2) 23.6 (151.06) 25.4 (170.2)
23.2 37.4 (61.2) 59.8
(157.7) 56.8 (144.8)
0.083 0.123 (48.2) 0.274 (230.1) 0.184 (121.7) 0.187 (125.3) 0.002 0.003
0.125 0.262 (109.6) 0.492 (293.6) 0.389
(211.2) 0.398
(218.4) 0.0035 0.0050
0.327 0.538 (64.5) 1.154 (252.9) 1.051 (221.4)
0.002 0.003 (66.6) 0.007
(360.0) 0.004 (193.3) 0.004
(146.6) 0.0004 0.0006
0.002 0.005 (122.7) 0.012 (431.8) 0.008
(254.5) 0.008
(281.8) 0.0007 0.0010
0.007 0.011 (61.5) 0.026 (304.6) 0.019 (206.1)
0.038 0.063 (65.8) 0.138 (263.2) 0.097 (155.3) 0.097 (155.3) 0.003 0.004 Stems 0.040 0.106 (116.3) 0.217 (342.8) 0.160
(226.5) 0.173
(253.1) 0.0033 0.0045 Roots
0.093 0.224 (140.1) 0.478
(413.9) 0.397 (326.8)
0.020 0.032 (60.0) 0.089 (345.0) 0.047 (135.0) 0.055 (175.0) 0.003 0.004
0.022 0.056 (154.5) 0.120 (445.4) 0.080 (263.6) 0.091 (313.6) 0.0030 0.0042
0.065 0.202 (210.7) 0.371 (470.7 ) 0.250 (284.6)
0.008 0.011 (42.8) 0.032 (315.5) 0.018 (133.7) 0.018 (133.7) 0.003 0.004
0.011 0.033 (200.0) 0.057 (418.2) 0.045 (309.1) 0.038 (245.4) 0.003 0.005
0.023 0.056 (143.4) 0.102 (343.4) 0.108 (369.5)
0.150 0. 231 (54.1) 0.540 (259.4) 0.350 (133.3) 0.361 (140.1) 0.0062 0.0085
0.209 0.462 (120.8) 0.898 (329.1) 0.682 (225.9 ) 0.708 (238.6) 0.0598 0.0825
0.514 1.030 (100.3) 2.131
(314.2) 1.826 (254.8)
2.34 2.57 3.25 2.97 3.16
2.22 2.62 3.14 2.88 2.78
2.21 2.75 3.57 3.21
( c o n t i n u e d )
Journal of Tropical Forest Science ll(2):345-355 (1999) 351
Table 3 (continued)
Grasses 49.2 0.905 0.019 0.394 0.216 0.074 1.608 (112.06) (176.7) (187.7) (323.6) (232.30) (221.7) (212.4)
CD 5% 0.0034 0.0035 0.0026 0.0033 0.0028 0.0113 CD 1% 0.0046 0.0048 0.0036 0.0046 0.0039 0.0156
Total biomass Control
Stones/
gravels Husk Leaf litter Grasses CD 5%
CD 1%
67.8 122.0 (79.9) 155.0 (128.6) 147.0 (116.8) 145.0 (113.8)
1.134 2.390 (110.7) 4.323 (281.2) 3.464 (205.4) 3.159 (178.5) 0.005 0.007
0.015 0.031 (102.6) 0.082 (431.8) 0.054 (251.3) 0.052 (236.3) 0.0035 0.0048
0.324 0.799 (146.6) 1.542 (375.9) 1.099 (239.2) 1.136 (250.6) 0.003 0.004
0.239 0.603 (152.3) 1.210 (406.2) 0.711 (197.5) 0.787 (229.2) 0.026 0.036
0.085 0.187 (120.7) 0.340
(301.4) 0.260
(206.9) 0.230
(171.5) 0.0006 0.0008
1.797 4.010 (123.2) 7.497 (317.2) 5.588 (210.9) 5.364 (198.5) 0.0859 0.1184
2.65 3.28 4.83 3.80 3.69
Note: Figures in parentheses show percentage increases over control.
Higher concentration and accumulation of nutrients in roots as compared to branches + twigs and stems may be attributed to remobilisation of nutrients due to development of a large number of sinks in the form of nodules (Marschner 1990).
High requirement of nitrogen and phosphorus for highest nodule activity has also been demonstrated for soybean (Cassman et al. 1980) and bean plants (Sundstrom et al. 1982). Addition of enough quantities of N, P, K through compost, as is evident from the analysis of compost (Table 1) and increased availability of nutrients and water due to reduction of evaporation and thermal stress in the root zone under mulches induced higher biomass production, nutrient uptake and nodulation (Singh et al. 1994b, Prihar et al. 1979, Gupta & Gupta 1983).
Decomposition of mulches like husks, leaf litter and grasses might have also added to the nutrient status of the soil and consequent uptake by plant parts.
This is also evident from the analysis of soils collected from different treatments after termination of the experiment (Table 4).
The total nutrient contents of the entire standing biomass exhibited much variation (Table 3). Nutrient accumulation was found to be maximum (7.50 g plant-1) due to the application of husk mulch, while leaf litter had a slight edge over grasses. Stones/gravels were not so effective as husk, leaf litter or grasses; still they promoted uptake (4.01 g plant-1) which was more than twice that of the control (1.79 g plant-1). Thus there was an overall increase of 317.2% in the case of husk mulch to 123.1% in stones/gravels over the control.
The highest values given by the husk mulch treated plants may be attributed to better moisture regime and higher availability of nutrients. Closer packing of husks due to their fine size gave rise to less moisture loss compared to leaf litter and grasses. Further, better moisture status of soils under the husk mulch and presence of the organic matter were responsible for greater microbial activities and release for absorption by growing plants. This is also evident from the higher
status of nutrients in husk mulch treated soils as compared to leaf litter and grasses
(Table 4). Heat transmission through the spaces available between leaf flakes and
stems of grasses and consequent evaporation losses from the soil surface were responsible for the lower moisture regime under these mulches leading to less mineralisation of organic matter and release of nutrients for uptake by plants.Table 4. Nutrient status of soils after growing Albizia procera in coal mine overburden for 12 months
Nutrient Mulch treatment
Control Stones/
gravels
Husk Leaf
litter
Grasses CD 5% CD 1%
Available nutrients (kg ha-1) N 470.40 476.70 P2O5 23.30 28.64 K2O 195.00 210.00
595.84 521.28 546.03 32.86 32.34 31.64 272.50 225.00 255.00
0.28 0.27 7.66 Cation exchange capacity & exchangeable cations (cmol
0.38 0.37 10.56
CEC Ca2+
Mg2+
K+ Na+
Total
6.90 2.80 1.33 0.40 0.22 4.87
9.80 4.30 2.80 0.54 0.26 7.86
13.50 6.10 4.40 0.87 0.29 11.66
11.30 5.30 3.23 0.59 0.24 9.23
12.20 5.66 3.93 0.49 0.28 10.23
0.132 0.069 0.027 0.045 0.250 0.018
0.182 0.093 0.038 0.063 0.340 0.024
The soil analysis data (Table 4) show an appreciable increase of N, P, K, CEC and exchangeable cations over the control within the short period of only one year due to the application of decomposable mulches. Fast and easy decomposition of husks, leaf litter and grasses as well as greater mineralisation of compost may be the reasons for the higher status of nitrogen. Though significant (p< 0.01), there were no wide differences in the available phosphorus status of the last three mulches (husk, leaf litter and grasses), while the control exhibited the lowest, even a slightly inferior status to stones/gravels. The available potash status of the soil was much higher in mulching treatments than in the control, probably because of greater leaching in the control. The maximum value ( 272.5 kg ha-1) for husk mulch may be attributed to the content of this nutrient in the husks and its incorporation in the soil. In spite of slightly higher uptake of potassium by plants treated with grass mulch, the higher value of available potassium in the soil under grass mulch as compared to leaf litter indicates a comparatively faster rate of decomposition and mineralisation of grass mulch.
Significant improvements in the CEC and exchangeable cations status of the soil were also due to the application of mulches. CEC increased from 6.90 in the control to 13.5 cmol kg-1 in husk mulch. Exchangeable Ca2+, Mg2+ and K+
registered significant (p < 0.01) increases due to application of mulches with the
Journal of Tropical Forest Science ll(2):345-355 (1999) 353
highest values in husk mulch followed by grasses, leaf litter and stones/gravels.
Use of stones/gravels showed significant positive response on nutrient status of the soil but was slightly inferior to other mulches , which provided additional input by way of their decomposition. Superiority of stones/gravels over the control can be explained in terms of greater mineralisation of the compost in the matrix due to comparatively better moisture regime than the control. Nutrient enrich- ment of the soil as influenced by mulching was calculated by deducting the
nutrient values of the control from the values under mulches. It is very difficult
to estimate the actual amount of nutrient enrichment due to several factors such as the accurate determination of nitrogen content of the soil, denitrification, leaching losses of nutrients, amount and longevity of nodules, availability of water and nutrients, etc. (Russel 1975). As the species was the same and the amounts of compost were added equally in all treatments, the enrichment of nutrients may be presumed to be due to the amelioritive effect of mulches by way of checking moisture losses through evaporation, reduction of thermal stress and leaching losses, release of nutrients from soil minerals and biodegradationof the decomposible mulches. In this respect, husk mulch was found to be the
best followed by grasses, leaf litter and stones/gravels (Figures 1 & 2). Singh et al. (1994a) have also observed the highest amount of nodules per plant inhusk mulch treated A. procera plants grown in coal mine overburden.
Stones/gravels
Figure 1. Nutrient enrichment of soil under the influence of mulches (Enrichment = values in treatments - values in control)
I
£~^ 6
~O
I5
COc O CO 4O
03
g,3 c CO
UJ 2 oB O HI 0 '
n
;|
| : \.
|, i l
=s;
Hi
*
• B
a
n^
• iil gl
n
Mg
Figure 2. Nutrient enrichment of soil under the influence of mulches (Enrichment = values in treatments - values in control)
Conclusion
Husk mulch and grasses are clearly superior to leaf litter and stones/gravels in respect of biomass production, nutrient uptake as well as soil enrichment. Thus, when planting mine overburdens, locally available husks, grasses and leaf litter may be used as mulches for fast plant development. Higher nutrient recycling through litterfall will enhance the rate of soil formation and biological activity.
References
ATTIWILL, P. M. 1968. The loss of elements from decomposing litter. Ecology 49:142-145.
BURKES, A. 1956. The release of cations during decomposing litter. Pp. 741-745 in Proceedings of 6th International Conference on Soil Science. Volume B. Paris.
CASSMAN, K, G., WHITNEY, A. S. & STOCKINGER, K. R. 1980. Root growth and dry matter distribution of soybean as affected by phosphorus stress, nodulation and nitrogen source. Crop Science 20:239-244.
CHAUDHARY, M. R. & PRIHAR, S. S. 1974. Root development and growth response of corn following mulching, cultivation or inter-row compaction. Agronomy Journal 66:350—355.
GUPTA, J. P. & AGGARWAL, R. K. 1988. Management of sandy wastelands for increased crop productions.
Pp. 257-270 in Shankarnarayan, K. A. (Ed.) Wastelands Development and their Utilization.
Scientific Publishers, Jodhpur, India.
GUPTA, J. P. & GUPTA, G. N. 1983. Effect of grass mulching on growth and yield of legumes. Agricultural Water Management 6:375-383.
JACKSON, M. L. 1973. Soil Chemical Analysis. Prentice Hall of India Ltd., New Delhi. 3rd edition.
498 pp.
MARSCHNER, H. 1990. Mineral Nutrition of Higher Plants. 4th edition. Academic Press, New York. 674 pp.
Journal of Tropical Forest Science ll(2):345-355 (1999) 355
MARSHALL, T. J. & HOLMES, J. W. 1988. Soil Physics. 2nd edition. Cambridge University Press, Cambridge (U.K.). 374 pp.
PIPER, C. S. 1950. Soil and Plant Analysis. University Press, Adelaide, Australia. 368 pp.
PRIHAR, S. S., SINGH, N. T. & SANDHU, B. S. 1979. Response of crops to soil temperature changes induced by mulching and irrigation. Pp. 305-315 in Lal, R. & Greenland, D. J. (Eds.) Soil Physical Properties and Crop Production in the Tropics. John Wiley & Sons, London, United Kingdom.
Russia., E.W. 1975. Soil Conditions and Plant Growth. 10th edition. ELBS, Longman. 849 pp.
SINGH, S. B., KUMAR, P. & PRASAD, K. G. 1989. Effect of mulching under different irrigation levels on height of some tree seedlings. Van Vigyan 27:49-54.
SINGH, A. K., MANJHI, R. B., BEHARI, B. & LAL, R. B. 1994a. Growth performance and biomass production of Albizia procera in coal mine overburden when influenced by mulching.
Indian Journal of Tropical Biodiversity 2:427—432.
SINGH, A. K., MEENA, S. L. , WILLIAMS, A. J., BANERJEE, S. K. & GUPTA, B. N. 1994b. Effect of mulches and watering interval on growth of Albizia procera in skeletal soil. Environment and Ecology 12:93- 98.
SINGH, A. K., BHOWMIK, A. K., CHAND, S. & BANERJEE, S. K. 1995. Response of mulches on growth and biomass production of Albizia procera in copper mine overburden. Van Vigyan 33:126-129.
SUBBIAH, B.V. & ASIJA, G. L. 1956. A rapid procedure for the estimation of available nitrogen in soil.
Current Science 25:259-261.
SUNDSTROM, F. J., MORSE, R. D. & NEAL, J. L. 1982. Modulation and nitrogen fixation of Phaseolus vulgaris L. grown in mine soil as affected by soil compaction and N fertilization. Communica- tions in Soil Science and Plant Analysis 13:231-242.
UPADHYAY, R. K. 1982. Release of nutrient elements from decomposing leaf litter of Eucalyptus globulus.
Indian Forester 108:550-553.
