phytoremediation of sodic nd saline sodic soil

1. Student
B.Balaganesh (11- 515- 301)
Members
1) Dr. K.Baskar
Professor (SS&AC)
2) Dr. S.Srinivasan
Asst. Professor (CRP)
Phytoremediation of Sodic and
Saline Sodic soil

2. Background
 Worldwide salt affected soils hinder the development of agricultural
production in arid and semi arid regions
Salt affected soils Sodic soils Saline soils
World (million ha) 831.4 434.3 380
India (million ha) 10 2.96 3.77
Tamil Nadu (ha) 3,68,015 13,231 3,54,784
Saxena and Rao., (2010)
 Found within the boundaries of > 75 countries and occupies > 20 % of the global
irrigated area
 Annual global income loss through Crop yield – US $ 12 billion

3. Classification of salt affected soils
Horneck et al., (2007)
Salt affected
soil
classification
Electrical
conductivity(EC)
Sodium
adsorption
ratio(SAR)
Exchangeable
sodium
percentage
Typical soil
physical condition
(soil structure)
None Below 4 Below 13 Below 15 Flocculated
Saline Above 4 Below 13 Below 15 Flocculated
Sodic Below 4 Above 13 Above 15 Dispersed
Saline- sodic Above 4 Above 13 Above 15 Dispersed

4. Saline soils
 White alkali - more concentration of soluble salts
(chlorides and sulphates of Na, Ca, Mg)
 Salts hindered the plant growth
 Non-Na salts prevent dispersion of soil particles
 Accounts for 40 % of world’s salt affected areas

5. Sodic soils
 Black alkali - ESP is high - Carbonates (CO3
2- + HCO3
-) of
sodium are the dominant.
 Excess Na+ ,OH- and HCO3
- -hindered plant growth
 Dispersion of soil particle and subsequent decreased
infiltration, aggregate stability, and aeration
 Accounts for 60 % of world’s salt affected areas

6. Saline - Sodic soils
 large amounts of soluble salts and high ESP.
 Plant growth is hindered by both salts and Na
 If soils are leached of salts, they will become sodic

7. Regions
Total area Saline soils Sodic soils
M ha M ha % M ha %
Africa 1,899 39 2.0 34 1.8
Asia, the Pacific and
Australia
3,107 195 6.3 249 8.0
Europe 2,011 7 0.3 73 3.6
Latin America 2,039 61 3.0 51 2.5
Near East 1,802 92 5.1 14 0..8
North America 1,924 5 0.2 15 0.8
Total 12,781 397 3.1 434 3.4
FAO Land and Plant Nutrition Management Service, (1997)
Distribution of salt-affected soils
(in million hectares)

8. Resource Inventories on Salt Affected Soils in India
 Saline soils - 2.96 million ha
 Sodic soils - 3.77 million ha
 Saline – sodic soils - 6.73 million ha
Salt affected soils in India
Singh et al., (2009)

9. State Saline soils (ha) Sodic soils (ha) Total (ha)
Andhra Pradesh 77,598 196,609 274,207
Bihar 47,301 105,852 153,153
Gujarat 1,680,570 541,430 2,222,000
Karnataka 1,893 148,136 150,029
Kerala 20,000 0 20,000
Maharashtra 184,089 422,670 606,759
Madhya Pradesh 0 139,720 139,720
Punjab 0 151,717 151,717
Rajasthan 195,571 179,371 374,942
Tamil Nadu 13,231 354,784 368,015
Uttar Pradesh 21,989 1,346,971 1,368,960
West Bengal 441,272 0 441,272
Total 2,956,809 3,770,659 6,727,468
Sharma et. al., (2004)
Extent of saline and sodic soils in various states of India

10. Status of saline soil distribution in Tamil Nadu
Name of the district Total area (ha) Saline soil (ha)
Chengleput 419,686 92,910
South Arcot 366,751 28,874
Thanjavur 479,033 185,316
Pudukottai 103,017 23,053
Ramanathapuram 396,023 148,955
Tirunelveli 641,302 137,352
Kanyakumari 130,282 64,162
Soil Survey Report ,(1982)

11. Problems due to salinity
 Soil particle flocculated and aggregate
 Poor soil physical properties
 Very poor water and air movement
 Lesser Root penetration
 O2 deficiency due to poor soil
structure
 Osmotic potential
 Collapsing cells
 Toxicity of bicarbonate
 Low micronutrient availability
 poor and spotty stands of crops,
 uneven and stunted growth and
poor yields
Soil Plants

12. Problems due to sodicity
Soil Plants
 Dispersion of soil particle
 Changes the exchangeable and soil
solution ions, pH
 Destabilization of soil structure
 Deterioration of soil hydraulic
properties
 Increases crusting of soil surface
 Shows specific ion effect
 High sodium levels compete for
nutrient uptake by plant roots..
 Increasing membrane
permeability and transport of
ions result necrosis of leaf tips
and edges.

13.  Amelioration of saline sodic soil is predominantly achieved through the
addition of readily available Ca to replace Na on the exchange complex
 Constraints with chemical amendments
o Low quality
o Restricted availability
o Increased cost
 Plant assisted low cost approach “Phytoremediation”
 Achieved by the ability of plant roots to increase the dissolution rate of
calcite to increase the Ca concentration
Phytoremediation

14. History - Phytoremediation of saline and sodic soil
 1920-30’s – Kelley and Brown (1934) - used Barley – ESP decreased from 65 to 6
 Kelly (1937) - Cyanodon dactylon - 2 years - ESP decreased from 57 to 1
 Sesbania as an important intervention for fodder, green manuring, and improvement
of salt-affected soils (Dhawan et al.,1958, Singh,1998).
 Effect of Palmarosa (Cymbopogon martinii) on improvement of salt affected soils
(Singh et al.,1999)
 Tamarix articulata reduced soil pH and ESP in saline sodic soil (Dager et al., 2001).
 Prosopis juliflora plantation indicated its effectiveness in amelioration of salt
affected soils (Basavaraja et al., 2007).
 Properties of salt affected soil amelioration under Eucalyptus species (Muhammad
Nasim et.al.,2007)
 Acacia nilotica for amelioration of sodic soils in Central dry zone of Karnataka, India
(Basavaraja et al.,2010)

15.  Phytoremediation assists in enhancing the dissolution rate of calcite.
 Soil–root interface resulting in increased levels of Ca 2+ in soil solution.
 It is a function of the following factors
PhytoSodic = RPCO2 + RH+ + RPhy + SNa+
Mechanisms involved in the Phytoremediation of salt
affected soils
RPCO2 - Dissolution of soil Ca by
increased partial pressure of CO2
RH+ - Proton release by plant roots
RPhy - Physical effect of roots SNa+ - Salt and Na+ uptake by shoots

16. Mechanisms involved in the Phytoremediation of salt affected soils

17. 1. Dissolution of soil calcite

18. 0
2
4
6
8
10
12
14
16
Control Gypsum Manure Cotton Alfalfa Sortan
PCO2 (k pa) Net Na+ removal (m mol)
Dissolution of calcite
Robbins (1986)
Sodic soil pH - 8.6 , EC – 2.4 dsm-1 , ESP - 33
Lysimeter experiments – calcareous sodic soils

19.  Release of H+ from plant roots in the rhizosphere
 Protons released by N2- fixing plant species in sodic soil assist in calcite
dissolution.
CaCO3 + H + Ca 2+ + HCO3
 Soil–root interface results in an electrochemical gradient
 Increases net H+ release through partial depolarization of the membrane
potential, which facilitates active H+ pumping (Schubert and Yan, 1997).
 Measurement of net H+ release at the root–soil interface - ash alkalinity
2. Proton release by plant roots

20. Mean Ash alkalinity of legumes adapted to saline sodic soil
Noble et al., (1998) and Quadir et al, (2005)
Plant species No of accessions Ash alkalinity
(C mol kg -1)
Callsandra calothyrsus 19 44.1
Callsandra acapukonsis 3 56.3
Leucaena diversifolia 5 71.6
Stylosanthes hamata 4 90.7
Stylosanthe scabra 3 102.3
Stylosanthe seabrana 7 124.7
Sodic soil pH - 8.7 , EC – 2.8 dsm-1 , ESP - 53

21.  Sodic soil - pH - 7.4, EC - 3.1 dS m-1, ESP - 27.6
Qadir et al. ,(2003)
Shoot and root DMP and Na removal by legumes

22. Name of grass Yield (t /ha)
Green fodder dry matter
Na removed
(kg/ha)
Marvel 10.0 3.7 5.0
Para 27.9 6.5 24.5
Vetiver 5.4 1.7 2.1
Karnal 8.7 3.1 25.8
Napier 9.1 2.3 -
Green fodder and dry matter yield of different grasses and Na removal
AICRP, (2002)

23.  Essential for maintaining soil structure and macrospore formation
 Roots act as potential tillage tool as they can grow through compacted soil
layers and improve the soil below plow pan.
 Plays important role in facilitating the process of Na+ leaching
 It can be triggered by deep-rooted vegetation
 Deep-rooted perennial grasses and legumes
- improve structure of the plow layer (Tisdall, 1991)
- hydraulic properties of sodic soils (Akhter et al., 2004).
3. Physical effect of roots

24. Hydraulic conductivity (Ks)
Soil depth increment (m)
Treatment 0.0 - 0.2 0.2 -0.4 0.4 - 0.6 0.6 - 0.8
Without gypsum application
Alfalfa 2.4 ab 3.8 a 2.0 a 3.4 a
Wheat straw added at 7.5 Mg ha-1 1.8 b 1.4b 1.1a 1.1a
Sesbania-wheat-sesbania 3.4 a 1.9b 1.9a 1.7a
Fallow 1.2 b 1.1b 1.6a 2.6 a
Gypsum applied at 25 Mg ha-1
Alfalfa 6.5 a 3.9 a 4.4 a 4.2 a
Wheat straw added at 7.5 Mg ha-1 3.5 b 2.1 b 1.8 b 2.9 ab
Sesbania-wheat-sesbania 7.9 a 2.0 b 1.8 b 2.1b
Fallow 2.9 b 1.2 b 1.2 b 1.5 b
Phytoremediation on hydraulic conductivity (Ks) of a saline-sodic soil
—deep-rooted alfalfa — Sesbania-wheat -sesbania rotation
 Saline sodic soil - pHs = 8.8, ECe = 5.6 dS m-1, SAR = 49)
Ilyas et al., (1993)

25. Treatment Available
water
(kg kg -1)
Bulk
density
(Mg m-3)
Porosity
(%)
Ks
(mm day-1)
Control (non-cropped) 0.155 1.62 38.9 0.04
Kallar grass (1 year) 0.175 1.61 39.1 1.5b
Kallar grass (2 years) 0.184 1.58 40.4 9.0b
Kallar grass (3 years) 0.195 1.55 41.5 18.0b
Kallar grass (4 years) 0.216 1.54 42.3 38.0b
Kallar grass (5 years) 0.214 1.53 42.8 55.6b
 Sandy clay loam texture
 Sodic soil - (pH - 10.4, EC - 22.0 dS m-1, SAR - 84)
Effect of various phytoremediation treatments on the available water
content, bulk density, porosity, and hydraulic conductivity (Ks)
Akhter et al., (2004)

26. Growth year 0-20 cm 40-60 cm 80-100 cm 0-20 cm 40-60 cm 80-100 cm
Available water (kg / kg) (SE-0.006, r= 0.97**) Structural stability index (SE-0.434, r= 0.96**)
0 0.155 0.151 0.153 32 19 33
1 0.175 0.173 0.170 58 36 34
2 0.184 0.183 0.183 67 65 71
3 0.195 0.191 0.199 68 51 55
4 0.216 0.199 0.211 119 67 77
5 0.214 0.203 0.212 151 47 91
Bulk density (Mg m-3) (SE-0. 013, r= 0.98**) Porosity (%) (SE-0.448, r= 0.98**)
0 1.62 1.73 1.68 38.9 34.6 36.5
1 1.61 1.72 1.60 39.1 35.3 39.7
2 1.58 1.65 1.59 40.4 37.7 40.0
3 1.55 1.59 1.56 41.5 40.1 41.3
4 1.54 1.53 1.55 42.3 41.5 41.9
5 1.53 1.53 1.54 42.8 42.2 42.4
Improvement of physical properties of a saline- sodic soil by
reclamation with kallar grass (Leptochola fusca)
Akhter et al., (2004)
 pH - 8.9 , EC - 0.14 dS m−1, SAR – 19.3

27.  Removal of aboveground biomass of plant species constitutes 2–20% of the
total salt uptake - Gritsenko et al.,(1999)
 Enhanced calcite accumulators through shoot harvest to net removal of salt
and Na+ is minimal.
 Alfalfa contribution only 1–2% - Qadir et al. (2003)
 Source of sodicity decrease through phytoremediation of calcareous sodic
soils
- leaching
- removal by harvesting the above ground plant biomass.
4. Salt and Na+ uptake by shoots

28. Removal of salt and Na+ in the aboveground harvest of some plant species
Gritsenko et al., (1999)
0
50
100
150
200
250
Japanese
millet
Amaranth Sunflow er Sudan grass Alfalfa
Shoot drymatter (q /ha) Salt removal (kg/ ha) Na+ removal (kg /ha)

29. Average values of ECe, ESP and salt removal before and after
harvest of the forage plant
Salih Aydemir and Halime Sunger., (2011)
 Non saline – pH - 7.67 , EC- 0.21 , ESP – 0.40
 Saline sodic I - pH – 8.3 ,EC – 5.27 , ESP – 23
 Saline sodic II – pH – 8.4 , EC – 8.37 , ESP - 26
Plantation reduced the soil EC and ESP
soil
EC (ds m-1) ESP (%) Salt
removal
(kg ha-1)
Biomass
weight
(g pot -1)
control After
harvest
control After
harvest
After
harvest
After
harvest
Non saline soil 0.62a 0.76a 0.40a 0.38a - 11.87a
Saline sodic soil –I 5.27a 0.40b 22.45a 18.05b 15.25a 3.97b
Saline sodic soil -II 8.37a 2.80b 25.59a 21.18b 32.48b 7.77c

30. Total salt removal by crops
C – Control, G – Gypsum ; CWIN – Cowpea white – inorganic-N ; CWNFIX – Cowpea white – N fixation;
CBIN – Cowpea brown – inorganic N ; CBNFIX – Cowpea brown – N fixation; HIN – Hyacinth bean
inorganic N ; HNFIX – Hyacinth bean – N fixation
Mubarak and Nortcliff (2010)

31. Grain: straw ratio of wheat crop grown on a saline-sodic soil
Treatment Grain yield ( Mg ha-1 ) Straw yield Grain :straw
ratio
Control (no gypsum or crop) 0.65 2.24 0.29
Gypsum at 13 Mg ha–1 3.68 5.69 0.65
Sesbania grown for 15 months 3.79 5.63 0.67
Sordan grown for 15 months 2.27 3.63 0.63
Kallar grass grown for 15 months 3.14 4.87 0.64
Saline-sodic soil (pH- 8.2–8.6, EC- 7.8–9.0 dS m–1, SAR - 61.7–76.1 in the upper 0.15 m of
soil
 Treatment effects as indicated by grain and straw yields of the postreclamation wheat
crop were in the order: sesbania _ gypsum > Kallar grass > sordan > control.
Ahmad et al.,(1990)

32. Leaf, stem and root chemical composition of Atriplex
nummularia grown in saline – sodic soi
Edivan Rodngues et al., (2010)
Elements Leaf Stem Root
Ca (g /kg) 5,24 1,55 3,40
Mg (g /kg) 6,13 1,13 2,50
Na (g /kg) 124,73 13,01 15,29
K (g /kg) 19,33 10,50 7,09
Cl (g /kg) 149,45 26,52 19,96
Cu (g /kg) 1,03 0,35 7,84
Zn (g /kg) 40,81 3,74 15,42
Soil pH – 8.6 , Ec – 42.56 ds/m , ESP - 72

33. Treatment Rice yield
(Mg ha-1)
Wheat yield
(Mg ha-1)
Rice-wheat rotation (without gypsum) 0.00. 0.00
Gypsum(12.5 Mg ha-1)+ rice –wheat 3.70 2.60
Para grass grown for 1 year 3.80 0.13
Para grass grown for 2 years 5.30 2.56
Karnal grass grown for 1 year 4.10 0.26
Karnal grass grown for 2 years 6.10 3.41
Effect of gypsum and grass-based cropping cultivation on alkali soil
Alkali soil - pH - 10.6, EC - 2.7 dS m-1 and ESP - 94
Kumar and Abrol (1984 )

34.  Ability of the species to withstand elevated levels of soil salinity (Qadir and
Oster, 2002).
 Depends on soil, crop, and climatic factors.
 Inter- and intra crop diversity can be exploited to identify local crops that are
better adaptable to saline-sodic soil conditions.
1. Selection of plant species
 Species with greater biomass production are efficient in soil amelioration
(Kaur et al., 2002).
2. Biomass production
Phytoremdiation efficiency depends largely on……

35. Biomass production of various plant species
Saline-sodic soil - (pH = 8.6 0.2, EC = 10.3 0.7 dS m-1, SAR = 66 )
 Forage yield of each species was directly proportional to the subsequent reduction
observed in soil sodicity
 gypsum > sesbania > kallar grass > millet rice > finger millet > control without
amendment or crop
Qadir et al., (1996)
0
10
20
30
40
50
60
Sesbania kallar grass Millet rice Finger millet Gypsum Control
Forage yield (Mg/ ha) Final soil SAR

36. Plant species Biomass (t ha-1) ECe (dSm-1) SAR
Para grass 48 2.7 94
Karnal grass 19.9 2.7 94
Kallar grass 7.4 7.4 17
Land grass 2.5 2.5 94
Blue panic grass 3.8 2.5 94
Rhodes grass 12.5 2.5 94
Coastal bermuda 4.0 2.5 94
Sesbania 33.9 7.8 62
Sordan 9.7 7.8 65
Millet rice 22.6 11.00 62
Finger millet 5.4 9.6 64
Biomass produced by different grass and forage species
on salt-affected soils
( Kumar and Abrol, 1984, Ahmed et al, 1990; Kumar 1988; Quadir et al.,1996,2007, 2008)

37. Salt tolerance varies with varieties in wheat…..
Slightly saline : < 8 dSm-1 , Moderately saline : 8 – 15 dSm-1 Highly
saline : < 15 dSm-1 ,
Akthar et al., (2007)

38. Treatments Soil sodicity level (SAR or ESP)
Pre -amelioration post amelioration
Control (no crop or no gypsum) 67.3 57.4
Gypsum at 13 mg/ha (no crop) 76.1 23.6
Sesbania (15 months) 61.7 28.1
Karnal grass (15 months) 66.4 42.0
Sordan (15 months) 64.6 33.0
Sandy loam , saline sodic -- pH- 8.2 -8.6 , EC – 7.4-9.0 and SAR 55.6 – 73.0
Ahmad et al., (1990)
Treatments Soil sodicity level (SAR or ESP)
Pre -amelioration post amelioration
Control (no gypsum or blue green algae) 89.7 86.5
Blue green algae inoculation (17 weeks) 89.7 88.4
Gypsum at 75% of soil GR (17 weeks) 89.7 42.9
Gypsum +blue green algae (17 weeks) 89.7 44.1
Comparative effectiveness of different amelioration strategies
Rao and Burns (1991)
Silt –loam , sodic soil - pH – 10.3 , EC – 3.5 , ESP – 89.7

39. Treatments Soil sodicity level (SAR or ESP)
Pre -amelioration post amelioration
Gypsum at 14 mg/ha +rice –wheat rotation 94.0 32
Farm manure 30 mg/ha+ rice-wheat rotation 94.0 43
Karnal grass (1 year)+rice-wheat rotation 94.0 43
Sandy loam , saline sodic soil in field - Singh and Singh (1989)
Rice – wheat rotation 58.7 22.0
Subsoilig +rice-wheat rotation (4 years) 62.1 20.4
Gypsum +rice –wheat rotation (4 years) 68.9 18.4
Gypsum +subsoiling + rice-wheat rotation(4 Y) 74.6 15.4
Sandy loam , saline sodic soil in field - Muhammed et al., (1990)

40. Treatments Soil sodicity level (SAR or ESP)
Pre -amelioration post amelioration
Control (no crop or gypsum) 30.9 13.1
Gypsum at 24 mg/ha (no crop) 30.9 13.7
Burgu grass (2 years) 30.9 12.9
Heavy clay , saline sodic soil in field - Helatia et al., (1992)
Control (no crop or gypsum) 24.5 18.5
Gypsum at 29 mg/ha (no crop) 24.5 11.4
Commen reed (2 years) 24.5 12.1
Victoria grass (2 years) 24.5 11.9
Gypsum + common reed (2 years) 24.5 10.8
Gypsum + victoria grass(2 years) 24.5 9.6
Heavy clay , saline sodic soil in field - Ghaly (2002)

41.  Based on salt tolerance of plant species
 Optimal potential utilization of salt-affected soils
Productivity enhancement of salt-affected soil through
plant species
Forage grass and shrub species
Medicinal and aromatic plant species
Fruit trees
Agro forestry systems

42. Plant species Soil salinity
(dSm1)
Soil pH Soil sodicity
(ESP)
Palmarosa 11.5 9.5 55
Lemon grass 10.0 9.0 50
Vetiver 12.0 10.0 55
Citronella 5.5 8.5 25
Cape periwinkle 10.0 9.5 -
German chamomile 12.0 9.5 -
Psyllium 8.0 9.2 -
Maximum threshold limits of the Medicinal and Aromatic plant species
Dagar et al., (2006)
 At which yield and quality of the crops are not affected

43. Survival (%) of fruit tree species under different ESP levels
AICRP, Indore (2002)
0
10
20
30
40
50
60
70
80
90
25 40 60 Mean 25 40 60 Mean
1999-2000 2000-2001
ESP levels (%)
Survival
rate
(%)
Pomegranate Sapota Ber Anola

44. Site I Site II Site III Site IV (control)
Acacia nilotica Albezia lebbek Eucalyptus tereticornis Desmostachya
ipinnata
Daldergia sissoo Terminalia arjuna Terminalia arjuna Chloris barbata
Holoptelea integrifolia Syzygium
heyneanum
Eucalyptus
camaldulensis
Leptochola fusca
Peltoforum
pterocarpum
Prosopis juliflora Glycyrrhiza glabra
Acacia ampliceps
Plant species response in the forest site
Singh and Garg (2007)

45.  Increasing pH and ESP and decreasing trends of organic carbon and N with soil
depth
Response the plant species under forest site
Singh and Garg (2007)

46. Particulars pH EC(dS m-1 ) ESP OC (%)
Initial 8.8 4.00 35.0 0.35
Cassia siamea 8.1 1.42 15.6 0.50
Acacia nilotica 8.3 2.00 25.0 0.49
Albizia lebback 8.5 1.40 20.0 0.57
Hardwickea binnata 8.3 2.10 22.0 0.63
Casuarina equisetifolia 8.5 1.54 17.0 0.52
Prosopis juliflora 8.5 1.29 10.2 0.71
Azadiracta indica 8.5 1.30 14.0 0.62
Acacia catechu 8.4 1.43 19.0 0.51
Eucalyptus tereticornis 8.2 1.24 0.67 0.67
Changes in properties of the alkali black soil after 7 year of plantation
AICRP, Indore (2002)

47. Treatment pH EC
(dS m-1)
SAR
(g kg-1)
0.C.
T0 - control-no amendments 8.6 6.5 30.0 3.4
T1 - Pyrites at 60% gypsum requirements ha-1 8.5 5.4 24.4 3.5
T2 - Sludge at 10 t ha-1 8.5 5.8 23.0 4.0
T3 - Hyacinth compost at 10 t ha-1 8.5 6.2 24.8 3.8
T4 - Hyacinth compost at 3 t ha-1+pyrites at 40% GR ha-1 8.3 5.4 21.0 4.6
T5 - Hyacinth compost at 3 t ha-1+sludge 5 t ha-1. 8.4 5.7 22.0 4.5
T6 - Hyacinth compost at 3 t ha-1 + sludge at 2 t ha-1 + pyrites
at 40% GR ha-1)
8.3 4.5 20.6 5.6
CD ( P = 0.05 NS 1.3 5.1 0.7
Effect of palmarosa on physico chemical properties of saline - sodic soil
Saline sodic soil - (pH 8.8, EC 7.9 dS m-1 and SAR 35)
Singh et al., (1999)
U.P. in India

48. Basavaraj et al., (2010)
Impact of Acacia nilotica plantation on saline sodic soil
Depth pH EC OC Available major nutrients
(kg ha -1)
CEC C mol
(p+) k g-1
ESP
0-15 7.9 2.05 2.29 447 17.0 273 55 27
15-30 8.0 3.08 1.05 318 11.6 237 52 33
30-60 8.4 5.20 0.93 260 12.1 208 47 39
60-90 8.4 5.55 0.41 147 10.8 156 45 40
Saturated extract cations and anions
Ca 2+ Mg 2+ K + Na + Co3
2- HCO 3- Cl SO 4
2- SAR
2.6 2.0 3.4 17.0 5.1 0.0 15.5 4.3 11
1.9 1.5 2.8 21.1 6.1 0.0 23.8 5.8 17
1.3 1.1 2.1 25.5 7.5 1.0 27.3 5.1 25
0.9 0.5 1.6 28.5 8.2 0.0 28.9 5.2 36
In Hosadurga taluk of Karnataka
Sodic soil with EC- 3.73 , pH - 9.2 , ESP – 50 and SAR – 32 Mean of 4 profiles

49. CEC (meq/l)(P+) kg-1 SAR ESP
Depth Mean of four Barren land
profile profile
Mean of four Barren land
profile profile
Mean of four Barren land
Profile profile
0-15 48.93 44.00 25.86 88.50 16.07 57.32
15-30 51.48 37.60 33.91 92.39 20.04 49.87
30-60 55.20 34.70 42.73 93.06 24.51 55.71
60-90 55.28 32.00 56.89 106.44 26.36 54.78
Impact of Prosopis juliflora in salt affected soils
Basavaraja et al., (2007)
in Hiriyur taluk of Karnataka
Sodic soil – pH- 9.8 , EC -17. 4 ,SAR – 72 and ESP - 64

50. Depth Site I Site II
Good plants poor plants Good plants poor plants
0-15 cm 17.93 45.54 14.87 27.87
15-30 cm 22.74 44.94 18.31 29.22
30-60 cm 23.94 39.76 18.33 12.98
60-90 cm 19.59 34.51 15.76 10.28
SAR (mmol/l) of salt affected soil under Eucalyptus camaldulensis
plantation
site-I - saline-sodic with ECe 16.1-37.7, pH 7.4-9.40 and SAR 20.2-47.6
site II- saline-sodic with ECe of 8.0-39.9, pH 8.0- 9.60 and SAR of 11.0-30.2.
Muhammad et al., (2007)
in Satiana of south east Faisalabad
Average of 8 plants

51. site-I - saline-sodic with ECe 16.1-37.7, pH 7.4-9.40 and SAR 20.2-47.6
site II- saline-sodic with ECe of 8.0-39.9, pH 8.0- 9.60 and SAR of 11.0-30.2
Effect on soil properties of salt affected soil under Eucalyptus species
Muhammad et al., (2007)

52. Depth (cm) Ca2+ Na+ Mg2+ SAR
2000 2003 2000 2003 2000 2003 2000 2003
Control
0-25 1.470 2.416 1.937 1.882 1.516 2.316 1.12 0.86
25-50 1.485 2.127 1.978 1.981 1.416 2.416 1.15 0.93
50-75 1.765 1.765 2.264 2.207 1.642 2.054 1.22 1.12
75-100 1.825 2.542 2.074 1.944 2.018 2.625 1.05 0.86
Treated
0-25 1.530 1.010 0.434 0.368 2.412 1.105 0.21 0.25
25-50 1.554 1.050 0.350 0.261 2.465 1.235 0.17 0.17
50-75 1.785 1.060 1.147 0.236 1.924 1.240 0.59 0.15
75-100 1.812 1.344 0.727 0.854 2.325 1.180 0.36 0.53
Saline soil amelioration using Glycyrrhiza glabra
Habibjon et al.,(2005)
In Gulistan of Uzbekistan

53. EC level (dSm -1)
Pre- harvest post harvest
SAR level
Pre-harvest post harvest
Original 1.64 Original 8.45
10 1.88 30 26.76
10 8.86 40 37.07
10 8.81 50 45.96
20 17.8 30 26.67
20 17.52 40 36.57
20 17.40 50 46.44
30 27.13 30 26.76
30 27.15 40 36.86
30 27.61 50 75.78
Acacia ampliceps improved the saline-sodic soil through decreasing
EC and SAR
Khalid mahmood et al.,(2009)
Sandy loam pH – 8.19 , EC – 1.70 , SAR – 10.95
SSRI , Pindi Bhattian

54. Performance of multi purpose plant species irrigated with varying
levels of salinity
Dager et al., (2006)
Plant species Growth period Fresh biomass kg /plant
month Irrigation treatments
T1 a T2 b T3c
Azadiracta indica 18 2.2 3.4 5.8
Azadiracta indica 30 8.9 9.3 9.8
Cordia sinensis 18 4.2 10.5 16.1
Cordia sinensis 30 14.1 16.9 17.3
Salvadora persica 18 1.0 1.3 2.7
Salvadora persica 30 15.1 16.5 20.2
Jatropha persica 18 1.8 5.2 8.8
Jatropha persica 30 4.0 6.4 10.0
a Irrigation with highly saline Water - Ec - 28 dsm-1 and SAR -26
b Alternate irrigation with highly saline Water - Ec - 28 dsm-1 and SAR- 26
c irrigation with moderate saline water - EC - 9.0 dsm-1 and SAR -26

55. Yield potential of crops as a function of root zone salinity
Quadir et al., (2008)
Crop Average root zone salinity (dS m-1) at
Name 50% 80% 100%
Triticale (grain) 26 14 6
Kallar grass 22 14 9
Durum wheat 19 11 6
Tall wheat grass 19 12 8
Barley 18 12 8
Cotton 17 12 8
Rye 16 13 11
Sugar beet 16 10 7
Bermuda grass 15 10 7
Sudan grass 14 8 3
Sesbania 13 9 6
Wheat 13 9 6
Purslane 11 8 6
Sorghum 10 8 7
Alfalfa 9 5 2
Spinach 9 5 2
Broccoli 8 5 3
Rice 7 5 3
Potato 7 4 2

56. Relative tolerance of crops to soil sodicity
ESP range Tolerant Crops
10-15 Safflower, Pea, Lentil, Pigeon pea, Urd bean
16-20 Bengal gram, Soybean
20-25 Groundnut, Cowpea, Onion, Pearlmillet
25-30 Linseed, Garlic
30-50 Indian Mustard, Wheat, Sunflower, Guinea grass
50-60 Barley, Sesbania
60-70 Rice, Para grass
70+ Bermuda grass, Kallar grass, Rhodes grass

57. Changes in cost: benefit ratio of vegetative bioremediation
Treatment Soil characteristics Rice - wheat Rice- wheat Rice -
wheat
Cost:
benefit
pH EC ESP % 1984-1985 1985-1986 1986-1987
Gypsum (14 Mg ha–1) +
Rice–wheat 9.25 0.45 32 4.23 1.34 4.83 1.42 5.21 1.95 1.00:1.14
Farm manure (30 Mg
ha–1) + Rice–wheat 9.50 0.51 43 3.27 1.03 3.86 0.91 4.73 1.37 1.00:1.05
Karnal grass for 2 years
+Rice – wheat 9.52 0.36 44 - - - - 4.88 1.28 1.00:0.75
Soil pH - 10.45, EC - 4.6 dS m–1, and ESP- 94 -99
Singh and Singh (1989)

58. Comparable effect of chemical and phytoremediation approaches
Summary of 17 experiments where chemical and phytoremediation treatments
have been compared for their effects on a decrease in soil sodicity. The bars for
respective treatments indicate percentage decrease over the respective levels of
original soil SAR or ESP values.

59.  No financial outlay to purchase chemical amendments
 Promotion of soil-aggregate stability and formation of macrospores
 Greater plant nutrient availability
 Environmental consideration in terms of C sequestration
 It is potentially the least harmful method
Merits

60.  More slow than chemical approaches
 Feasibility of phytoremediation is limited when soil is highly sodic, as this is
likely to result in poor growth of the phytoremediation crop’s
 is limited to the surface area and depth occupied by the roots.
 Slow growth and low biomass require a long-term commitment.
Demerits

61. CONCLUSIONS
 Phytoremediation is the most economical approach
 Toxic ions like Na+ and Cl- are removed by the salt tolerant plants
 Enhanced Ca2+ availability improves the soil physico-chemical properties
 Soils become fertile for subsequent crops
 More suitable to reclaim salt-affected wastelands with long duration tree
crops

62. Useful reference