Managing Soil and Water Resources for Increasing Productivity in Coastal Agro Ecosystem of West Bengal

1. SEMINAR- II
Speaker: Dr. Tarik Mitran
Agricultural Chemistry & Soil Science
Date: 01.07.2011 Course No-ACSS-849
Managing Soil and Water Resources for Increasing Productivity
in Coastal Agro Ecosystem of West Bengal

2. Introduction
 Ecology extremely fragile
 Environmental decline due to weather adversities
(cyclone, Tsunami) & anthropogenic activity
 Heavy rains in monsoon and meager rains
afterwards
 Saline GW table at shallow depth
 Lack of irrigation water, drainage congestion &
water logging
 Backward and disadvantaged areas with low
agricultural productivity & poor Livelihood.

3. Coastal Saline Zone of India

4. Location of study area
Coastal area of West Bengal

5.  Poor farming communities.
 Population dominated by backward classes
 High unemployment
 Poor livelihood security
 Huge migration of labour forces
Demographic features of West Bengal Coastal

6. Major Issues

7. Critical Gaps in Agriculture
• Soil degradation due to
salinity
• Scarcity of good quality of
water in post-monsoon
period
• Insufficient storage capacity
of freshwater
Only mono crop of
Kharif rice
• Drainage congestion in
kharif
• Lack of suitable salt tolerant
rice varieties
Long duration
traditional rice varieties

8. Rice
94%
Veg.
6%
Fallow
0%
Rice
18% Veg.
2%
Fallow
80%
Dry SeasonWet Season

9. Productivity of major crops in the coastal saline zone of West Bengal

10. Reasons for salinity
Evaporation
Transpiration
salinity build up
Capillary rise
 upward movement of saline
ground water
Salinity due to:

11. Opposite seasonal movements of salinity & water
table in Coastal Saline region
Source: Sen and Oosterbaan (1992)

12. 0
5
10
15
20
Jan
FebM
arch
April
M
ay
June
July
Aug
Sept
O
ct
Nov
Dec
Soilsalinity(ECe,dS/m)
Variation in soil salinity in different months of the year
Source: Bandyopadhyay et al (2003)

13. Potential strength of the area
0
100
200
300
400
500
J F M A M J J A S O N D
Month
Rain/Evapomm)
Evaporation (mm) Rainfall (mm)
Sundarban
(An. Rain: 1800
mm)
0
200
400
600
J F M A M J J A S O N D
Months
Rainfall/Evaporation
Rainfall(mm)
Evaporation(mm)
Andaman
(An. Rain: 3080 mm)
 Excess rainfall in wet season that goes waste into the sea can
be harvested
 Heavy texture soil, GW at shallow depth & high humidity
 Ample supply of brackish water

14. Surface & subsurface drainage
Salt tolerant crop cultivars
Agro-forestry, Paddy-cum fish farming
Conjunctive use of saline water

15. Raised bed created
Land shaping Farm pond Water
harvesting
Introduction of
suitable rabi
crops
Less
salinity
Improved
drainage
Introduction of
HYV of rice
Land Shaping Technique

16. Pond (20 % area) for rain
water harvesting & fish
cultivation
Dike for growing
vegetables
Rain water harvesting in dug out farm pond
Land raising for HYV
rice in kharif

17. Item Dimension
Size of holding 1 ha
Surface area of pond (42.3 m x 42.3 m) 1970 m2
Depth of pond 3 m
Side slope 1:1 m/m
Volume of pond 4700 m3
Volume of bunds 700 m3
Irrigable area 0.8 m2
Height by which the irrigable area is raised 0.5 m
Depth of water remaining for pisciculture 1.5 m
Volume of water available for irrigation 2560 m3
Irrigation requirement of rabi crops (chili, barley, watermelon) 1200 m3
Water losses from pond during rabi (evaporation, seepage:
5mm/day during 150 days) 1300 m3
Specifications of farm ponds and corresponding water balance for
Irrigated rabi crop (CSSRI 1981)

18. Sweet water (SW)
Soil saturated with sweet water
No upward movement of brackish water
Irrigation reduces salinity
upward movement of SW
.
Ridge & furrow technique on saline low lands

19. Land situation
High land Feb March April May June July
0-15cm 2.70 5.10 5.25 5.85 4.50 1.86
15- 30 cm 2.85 5.25 5.50 5.72 4.88 2.06
Medium land
0-15cm 3.08 5.38 5.63 7.00 6.25 1.94
15- 30 cm 3.13 6.13 5.83 7.25 6.35 2.44
Normal Land
0-15cm 7.28 7.85 8.50 16.50 11.25 2.36
15- 30 cm 9.25 10.38 10.63 16.63 12.38 2.61
Effect of land shaping (farm pond) on soil salinity (ECe dSm-1
)
Source: Bandyopadhyay et al (2009)

20. Season Crop
Crop yield
(q)
Gross
return(Rs)
Cost of
cultivation(Rs)
Net
return(Rs)
Kharif
Ladies finger
Brinjal
2.08
3.00
2496
3000
543.0
271.0
1953.00
2729.00
Rabi
Tomato
Ladies finger
1.20
2.08
1200
2496
302.0
543.0
898.00
1953.00
summer Chilli 2.00 1800 1357 443.00
Bund
plantation
Pumpkin
Papaya
Banana
Cowpea
Green leaf
0.50
3.00
9 bunch
0.5
0.05
200.0
900.0
1350
250.0
50.00
50.00
150.0
81.00
15.00
10.00
150.00
750.00
1269.00
235.00
40.00
pond
Bitter gourd
Fingerling
Big fish
0.62
1200 nos
0.75
620.0
1200
3150
35.00
450.0
950.0
585.00
750.00
2200.00
Yield and Economics of pond and raised bed system
Source : Sahoo et al (2004)
A space of 183 m2
for vegetables and 224 m2
for bund vegetables and
90 m2
for scaffold was used
Total area: 2212 m2
, pond size :1622 m2
and raised bed size: 590 m2

21. Soil management
Organics
Green Manure,
FYM,
Chemical
amendments
Soil test and
crop need based
fertilization
Integrated
Nutrient
Management
Prevents soil
deterioration &
improve Crop
yield

22. Treatments
EC (dSm-1
)
ESP
(%)
Grain Yield of rice
(Kg ha-1
)
No Gypsum Gypsum No Gypsum Gypsum No Gypsum Gypsum
Control 2.49 1.85 24.59 10.72 2457 3537
Farm yard manure
@ 15t ha-1
1.02 0.96 15.99 7.97 3242 3977
Press mud
@ 15 t ha-1
1.04 0.74 14.42 6.30 3320 3990
Composted coir
pith @10 t ha-1
0.77 0.63 7.63 4.59 3933 4150
Green leaf manure
@ 5 t ha-1
1.12 0.76 1382 6.55 3533 4758
Effect of organic amendments on soil salinity and yield of rice
Source: Singaravel et al (2001)

23. Location Treatment 1994-95 1995-96
West Bengal
crops Rice (Kharif) Rice (Rabi) Rice (Kharif) Rice (rabi)
NPK 1.8 4.6 2.8 5.1
NPK+ Green
manuring
2.3 5.1 3.2 6.1
Orissa NPK 4.0 1.6 3.1 4.2
NPK+ Green
manuring
5.4 2.0 3.5 4.5
Andhra
Pradesh
crops Rice Ground nut Rice Ground nut
NPK 3.1 2.4 3.1 3.2
NPK+ Green
manuring
3.4 3.3 4.0 3.4
Effect of combined use of inorganic fertilizer and organic manures
on yield ( t ha-1
) of crops on some coastal soils of Eastern India
Source: Subba Rao and Mohanty. (2006)

24.  Leaching
 Deep ploughing
 Sand mixing
 Tillage
 Introduction of salt tolerant cultivars
Other possible options

25. Acid sulphate soil is a problem in Coastal Areas
Potential acid sulphate soils are
naturally occurring soils containing
iron sulfides(pyrite) pH near neutral
Become actual acid sulphate soils
when dried & pyrite is exposed to
air & oxidized, resulting in
production of sulfuric acid pH
below 3
2 FeS2 +9 O2+4H2O 8H+ +4 SO4+ 2 Fe(OH)3
Acidity build up
Keeping the area flooded
Liming
Double dose of P fertilizer
Controlling water table by drainage
GM along with lime and P
Application of Rock phosphate

26. Water Management Strategies

27. WaterWater
managementmanagement
WaterWater
managementmanagement
ConjunctiveConjunctive
use of salineuse of saline
waterwater
Rain waterRain water
HarvestingHarvesting
MulchingMulching
BrackishBrackish
water forwater for
fisheryfishery
SuitableSuitable
irrigationirrigation
methodmethod
SkimmingSkimming
wellwell
drainagedrainage
Surface &Surface &
subsurfacesubsurface
drainagedrainage

28.  Removal of excess salt beyond root zone
 Leaching through subsurface drainage
 Integrated use of surface water and saline ground water
 Dilution through proper blending and mixing
 Cyclic use of good and poor quality water according to water
availability and crop demand.
 Application of conjunctive water through subsurface drip
method
Principles of drainage & conjunctive use of saline water

29. Treatment Average ground
water level (m)
Soil salinity(dSm-1
) in
surface soil (0-30 cm)
Wheat yield
(t ha-1
)
at sowing at harvest at sowing at harvest
Drained 1.22 1.58 0.65-1.20 2.20-3.50 2.32
Undrained 1.22 1.58 2.50-3.25 6.00-8.50 0.00
Effect of drainage on soil salinity and wheat yield
S. K. Gupta (2007)

30. Skimming Technique of fresh water
 Skim of fresh water accumulated over the native saline GW zone instead of random
pumping.
 Skimming through single well, multi strainer well, scavenger well, radial collector
well are the possible option.

31. Treatment
(canal water: ground
water)
Grain yield
(t ha-1
)
Straw
yield
(t ha-1
)
EC of irrigation
water
(dSm-1
)
4:0 3.04 3.40 2.4
3:1 4.02 4.33 1.8
1:1 5.32 5.55 1.2
1:3 5.43 5.75 0.58
0:4 5.63 5.96 0.42
S. Em(±) 0.17 0.18 -
CD at % 0.48 0.50 -
Effect of conjunctive use of canal water and ground water
on grain and straw yield of summer paddy
Patra et al (1999)

32. Treatment Average soil
Moisture%
Average surface
soil salinity
(dSm-1
)
Green forage
yield( t ha-1
)
Yield %
Control 14.81 1.19 933.7 100
Organic mulching
with dried date
palm leaves
16.55 1.15 1056.4 113
Plastic mulching 14.9 1.55 947.7 102
Effects of organic mulches on soil moisture, salinity and
yield of sorghum crop
Al-Rawahy et al (2011)

33. Alternative Land use for low land waterlogged soils
 Paddy-cum Fish integrated Farming
 Agro-forestry

34. Vegetables on dike Trench for growing &
shelter of fishes
Paddy-cum-fish
Land shaping for paddy cum-fish cultivation.

35. Salinity(ECe, dSm -1
) Tree species
20-30 Acacia farnesiana (Desi babul) Prosopis juliflora (Mesquite, pahari
kikar), Parkinsonia aculeta(Jerusalem thorn,parkinsonia)
14-20 A. nilotica(deshi kikar), A. tortilis (Israeli kiker), Casuarina glauca, C.
obese, C. equisetifolia, Eucalyptus camaldulensis (river red gum,
safeda)
10-14 Casuarina cunninghamiana (casuarinas Saru) Eucalyptus
teretocornis(Mysore gum, safeda) Terminalia arjuna (Arjun)
5-10 Albizia caribea, Dalbergia sissoo, Guazuma ulmifolia, Pongamia
pinnata (papri), Samanea saman
<5 Acacia auriculaeformis (Australian kikar), A. deamii, A. Catechu
(Khair), Syzygium cuminii(Jamin), Salix Spp.(Willow, salix),
Tamarindus indica (Imli)
Recommended tree species for saline and waterlogged soils
Singh & Hussain (2008)

36. Crop Varieties
Rice
(i) ECe:(6.0-8.0 dSm-1
) high salinity, 0-15
cm water regime
(ii) ECe: (4.0-6.0 dSm-1
) moderate
salinity, 15-30 cm water regime
(iii) ECe:( around 4.0 dSm-1
) moderate
salinity, 30-50 cm water regime
(iv) Acid sulphate soil
CSR 1, CSR 2, CSR 3, CSR 4, CST 7-1
Canning-7, Jaya, IET1444
Sumati, CSR-6, SR 26B, Dudhesar, NC
1281, NC 678, Gavir Saru, Gopal Bhog etc.
Utpala , CSR-6, SR 26B, NC 1281, Gavir
Saru, Matla etc
Mashuri, Canning, SR 26B,
Mustard 8-85,T-59, Varun
Chilli CA 960, Suryamukhi, Pusa Jwala
Watermelon Sugerbaby, Suger Sweet
Cotton 081, J.K. 260-2, F-414 etc
Barley Karan 19, Ratna, DL 120, K-125 etc.
Identified/ Improved crop varieties for coastal saline soils
Singh & Hussain (2008)

37. Sustainable Resource management through
Integrated Farming system approaches;
Grass root level policy & implementation
through Institutional linkage.
Conclusions

38. THANK YOU