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Moisture conservation in the foothills of lower shiwaliks is challenge for the farmers/scientists for upgrading the production potential of the area.
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Soil and Water Conservation technologies for sustainable crop production in rainfed areas – an overview
Rajan Bhatt and Sanjay Arora *
Department of Soils, Punjab Agricultural University., Ludhiana – 141004*Division of Soil Science and Agricultural Chemistry, Sher-e-Kashmir University of Agricultural Sciences and Technology, FoA, Chatha – 180 009, Jammu
The rainfed areas have many constraints for optimum crop production. The
productivity levels are very low and unstable due to the erratic distribution of
monsoon rainfall in space and time. The soils of the rainfed area are not only thirsty
but hungry as well. Soil erosion leading to high runoff, sizeable loss of soil and
nutrient is primarily responsible for low productivity and poor economic status of
the farmers in rainfed areas. Due to fragility, marginality, low accessibility and
resource heterogeneity, there is little scope for enhancing crop productivity with the
existing infrastructural facilities and technologies. Appropriate soil and water
conservation technologies adopted to meet the food, fodder and fuel demand of the
increasing population.
Key words : Rainfed; Soil; Water; Conservation; Crop yields
Rainfed area occupies an important place in Indian Agriculture. It constitutes about 68
per cent of total cultivated area of 143.8 m ha and contributes nearly 44 per cent of the
total food grain production in India (Reddy et al 1995). The productivity levels of the
rainfed areas are very low and unstable due to the monsoon rainfall which is erratic,
unpredictable and also highly fluctuating over the years. Soil erosion leading to high
runoff, sizeable loss of soil and nutrients is primarily responsible for low productivity and
poor economic status of the farmers in rainfed areas. Soils, the main anchor of production
and productivity, are getting thinner and poorer day by day. Water, the lifeline, is getting
scarcer everyday because of it’s mismanagement. It is realized to manage the natural
resources on geo-hydrological unit basis for improving the productivity of these lands
through soil and moisture conservation measures, establishment and transfer of improved
crop productivity technologies. Soil and water conservation measures aim at management
of rainwater, soil and vegetation resources in a manner that perceptible changes with
regard to water resources development take place in the rainfed areas so as to increase
land productivity on a sustainable basis. Not only the surface water storage should
increase as a result of soil and water conservation interventions, but increased ground
water recharge should take place. In general, planning of resource management has
generated wide appreciation, particularly for assured dividends and meeting the food
grain targets of the nation. This paper gives an overview of soil and water conservation
technologies for efficient management of the natural resources in dryland regions.
Soil and water conservation technologies
There is an urgent need to check ground water depletion, runoff water reduction, soil loss
reduction, management of rainwater, generation of surface water resources and
improving crop productivity to improve socio-economic status of the farmers in the area.
Management through participatory approach in the rainfed region is better solution. Many
technologies pertaining to soil and water conservation in the rainfed areas are found to be
very effective. These have been found to reduce soil and nutrient loss, removal of top
fertile soil, insitu conservation of soil moisture and ultimately improving the crop
productivity.
Contour cultivation
Agricultural operations such as ploughing, sowing, hoeing, weeding, etc when performed
across the slope on contours helps in controlling runoff and soil loss. The furrows
developed during ploughing or sowing intercept, hold and allow rainwater to enter into
the soil slowly. A field experiment conducted in sorghum on 2.4 % slope in alluvial soil
revealed that there is 25 % increase in yield by sowing it on contours across the slope. In
addition it reduces soil, nutrient and runoff losses considerably compared to along the
slope treatment. In another study in which 680 mm rainfall received during the crop
season, contour cultivation of sorghum resulted in only 249 mm runoff and 5.5 t/ha soil
loss as against 348 mm runoff and 14.1 t/ha soil loss in up and down cultivation practice
(Table 1). The grain yield of sorghum under the farmers practice was 2.0 t ha-1 as against
1.6 t ha-1 under the later (Bhatia and Choudhary 1977). Similar results were also obtained
by Das et al (1974) in maize crop (Table 1). In a study conducted in rainfed submontane
region of Punjab, Arora and Hadda (2003) observed an increase in maize grain yield to
the tune 5.4 per cent when cultivated across the slope as compared to farmers’ practice.
Ridge and furrow system
Preparing furrows between the rows after crop establishment across the slope helps to
control soil erosion and runoff and increases crop yields (Table 2). Such a practice has
been found to be useful even on flat lands in saving the crops both during the drought as
well as wet season. Furrows provide more opportunity time for runoff water to soak into
the soil while the ridges provide aeration to crop during water inundation or flooding of
short duration. Bhan et al (1995) observed an increase of about 48 % in yield of sorghum,
while Gupta & Bhan (1997) observed an increase of 20 % in yield of maize when sowing
was done in ridge and furrow system over the flat sowing (Table 2). Ridge and Furrow
sowing of pearl millet increased the root depth by 5.5 % and grain yield by 16.6 % over
flat sowing because of more moisture storage in soil under ridge and furrow sowing
method over flat sowing.
Increase of maize to the tune of 10.6 % was observed in ridge and furrow sowing in
rainfed region of Punjab over the farmers’ practice of flat sowing (Arora and Hadda
2003). The modified version of ridge-furrow system is tied-ridging, where ridges are tied
at 15-20 cm interval to allow rainwater collection in the furrows and its infiltration into
the root zone. It is observed that the system not only conserves rainwater but also
substantially reduces sediment and nutrient losses induced by runoff (Table 3;
Anonymous 1994). Also there was increase in yield of soybean crop with these improved
practices over flat sowing.
Vegetative bunding
Apart from higher cost another problem with earthen bunds is that they are breached
frequently in rainfed areas where soils are coarse in texture and low in organic matter
resulting in soil loss with runoff water. Such problems could be avoided with vegetative
barriers across the slope. Chand (1997) evaluated different vegetative barriers for
reducing runoff and soil loss in alluvial soils (Table 4). It was observed that Vetiveria
zizanoides was the most effective in decreasing the losses caused by the soil erosion as it
decreases the soil loss and runoff by 53 and 41 % respectively.
Tillage and mulching
Among the various mechanical and agronomic measures, tillage and mulching are the
two most important practices that have been reported to reduce the soil erosion and
increase the soil moisture storage in-situ and improve the productivity of crops in rainfed
areas. Deep tillage improved the soil physical properties in terms of increased infiltration
and moisture storage, which resulted in root development in rainfed region of Agra.
There was an increase of 35.1 % in root depth and 26.4 % in grain yield of pearl millet in
deep tillage over shallow tillage (Singh & Verma 1995). Infiltration rate increases with
the increase in tillage depth and was maximum under deep tillage (1.92 cm/hr), which
can be attributed to improved porosity, reduced bulk density and favorable tilled
conditions.
In rainfed submontane Punjab, maize and wheat yield improved with deep tillage due to
pronounced effect on soil moisture storage over shallow tillage (Hadda et al 2005). As
compared to the unmulched control, the application of mulch on the whole covered plot
resulted in 4.0 to 5.1 % and 3.5 to 7.1 % higher soil moisture content in rainfed region of
Punjab. Mulch spread on the whole plot increased the grain and straw yield of maize by
60.5 and 31.8 per cent as compared to unmulched control. Minimum tilled plots (Tm) had
only 4.0 % higher grain yield than the conventionally tilled plots (Tc) (Bhatt et al 2004).
Compared with control, mulch applied on the whole plot reduced runoff by 33%. Runoff
and soil loss were 5% and 40% higher under conventional tillage than under the
minimum tillage (Bhatt and Khera, 2004). Though other modes of straw mulch
application i.e. mulch spread on lower 1/3rd of plot (M1/3rd), mulch applied in strips (Ms),
vertical mulching (Mv) and controlled soil loss better than unmulched control (Mo),
however their effectiveness was less than Mw. Minimum soil temperature of the surface
layer was 1.4 to 2.4 OC lower under Mw than under Mo. Straw mulching reduced
maximum soil temperature and helped in conserving soil moisture. The plant height was
68.1, 44.5, 37.1 and 17.4 % higher in Mw, M1/3rd, Ms and Mv respectively as compared to
the control Mo while minimum tilled plots had 4.8% higher plant heights as compared to
the conventionally tilled plots. Leaf area index in Mw plots was 79.3 % higher LAI as
compared to Mo plots whereas minimum tilled plots had 32.3 % higher as compared to
the conventionally tilled plots (Bhatt and Khera, 2004).
Bhan & Uttam (1998) have reported that inter-cultivation resulted in increase yield of
crops to the tune of 13.6 % in pearl millet, 53.3 % in sesame and 8.5 % in barley over
control. Sharma et al (1985) reported that application of soil and straw mulch not only
increased the yield of chickpea and wheat but also improved the water use efficiency of
rainfed crops (Table 5).
Pre-monsoon ploughing
In this practice ploughing is given to each field before onset of summer monsoon
rains. This makes the field surface rough and cloddy. It exposes more surface
area, helps intercepting and increasing residence time for runoff. This improves
imbibation of rain water into the soil and at the same time controlling pests and
diseases. Ploughing enhances infiltration and reduces runoff and soil erosion.
Under natural fluctuating high intensity and long duration rainfall, runoff was
grater from unploughed plots than from ploughed ones. Soil loss was, however,
greater from ploughed as compared with unploughed plots (Gupta et al 1963;
Mannering et al 1960). This was ascribed to more surface area exposed by clods.
According to Mihara (1951) the practice decreases the sealing effect but
occasionally increases the soil detachment. Strong and well stabilized
field/contour bunds with water disposal structures are essential for reducing soil
loss caused due to pre-monsoon ploughing. These observations get support from
the works done in the area. In addition, presently farmer ploughs his fields in a
round about manner and is not doing contour ploughing. Later checks runoff and
soil loss better than up and down ploughing.
Haloding
It is an important kharif season practice in maize crop in the area. In this an
inverted plough is run however the inter-row spacing in a month old maize crop.
The practice destroys weeds does earthing up and creates shallow ditches
between the row. The ditches when produced against slope or on flat surface
intercept and detain running water and store more water from the rainfall shows.
In addition the earthing up supports the plants, aerates the rooting zone and
decreases resistance to growing roots thereby crates conditions for a better root
growth. The practice of haloding decreasing weeds, conserved more water and
increased maize yield by 24 per cent than control (Table 7) (Anonymous 1991).
Gill dabna (Soil mulching)
It is an indigenous practice used for conserving soil moisture and raising a
successful rabi crop in Kandi area. In this practice, at maturity of maize farmer
harvests it and ploughs the field on the same day. This ploughing he does during
evening hours, and next day in the morning he planks it. During the night hours
exposed clods; pick up moisture from cool air and get softened which break on
planking easily. He covers all his fields by; ploughing and planking similarly.
After completing the harvest, he again repeats (3 to 5 times) the process of
ploughing and planking to prepare a fine surface soil mulch. This checks/reduces
surface evaporation and conserves profile water. The practice is scientifically
sound. By creating soil mulch at the first opportunity, the farmer conserves the
profile water by checking upward movement of water through breaking the
continuity of capillaries towards the soil surface. Thus decreasing the
evaporation losses and helps in better germination of the rabi crops.
Selection of crop
The farmer must have learnt the hard way that what they should grow. The
process of selection should have taken years so as to adjust to highly erratic rains
in the area. It is a highly speculative economy and the problem was one of
bringing some stability in farm income and reserves of food and money to
survive during dry seasons and years. The kind of crop that can be grown
depends on total water demand timing of the need in relation to supply, and on
the ability of the crop to endure drought without damage. The total water
requirement of various crops differ mostly because of duration and timing of
their growth periods in relation to evaporation demand. At one location, the
crops vary as much as 75 per cent in their total evapo-transpiration (ET). The
difference in demand when peak use time occurs also affect the selection of this
crop. The water use is also effected by the weather conditions e.g. peak daily use
at swift current is almost double or triple the average daily use in these areas.
These peak rates are associated with hot and dry winds. Many crops have a
critical period when the plants cannot endure water stress without harm. For corn
this period is at tessling and silking, for wheat the critical stage is at heading and
at filling of kernel. Thus, the timing of water availability to critical demand by
the crop is very important. Old-timers experienced in dryland agriculture have
found these relationships by hard experience. Since timely rains in relation to
crop demand are very important in rainfed areas, as there are often poor relations
between crop yields and total precipitation.
People of kandi area depend on 15 or 16 kinds of crops for our
primary supply of food. Of these 15 or 16 species, long season crops are poorly
adopted to the conditions of the area because of their high total water needs.
Short season crop varieties for grains, wheat and maize; for fodder sorghum,
bajra, guara and taramira, black gram (mash), gram and lentil as pulse crops and
sesamum and raya as oil seed crops are common in the area.
Another example of preference is that of mash over moong in the
area. Despite of the fact that moong yields more and is drought hardy, farmer of
the area prefers to grow mash than moong. This he does because people in the
area use mash in their more oftenly. No social or cultural event is complete
without cooking and serving mash as a dish. Therefore, cultivation of mash has
come to stay with the farmer of the area.
Blind hoeing ('Anee godi)
Blind hoeing of sugarcane fields with 'kasaula', a specially designed tool, for
hoeing is done during the month of April, when the sugarcane seedlings are in
the process of emergence. This breaks crust, checks evaporation from soil
surface and improves germination.
This practice has support from scientific knowledge. As soils of the
area have very low organic matter, soil aggregates are not only less but also very
weak which break under the impact of rain drops and get dispersed easily. In this
way rain showers on dry soil surface invariably create soil crust. This soil crust
seals the soil surface to infiltration and checks emergence of seedlings recently
sown crops.
CONCLUSIONS
The above described technologies for soil and water conservation if adapted in the
rainfed areas will surely help in reducing soil loss and runoff apart from increasing the
crops yields. This will ultimately improve the socio-economic status of the resource poor
farmers of the rainfed region.
REFERENCES:
Anonymous, 1991. Annual Progess Report, Deptt. of Soils, Pb Agric. University, Ludhiana.
Anon. 1994 Ann Prog Rep Integ Res Project Soil Conser Watershed Manag, College Of Agriculture, Indore
Arora S & Hadda M S 2003 Indian J Dryland Agric Res & Dev 18 70
Bhan Suraj & Uttam S K 1998 Indian J Soil Cons 26 22
Bhan Suraj Uttam S K & Radhey Shyam 1995 Indian J Soil Cons 23(1) 24
Bhatia K S & Choudhary H P 1977 Soil Cons Digest 3(2) 16
Bhatt R Khera K L & Arora S 2004 Int J Agri Bio. 6 1126
Bhatt R and Khera K.L. (2005) Soil & Tillage Research, Netherland (In Press).
Bhatt R and Khera K.L. (2004) Indian journal of Ecology. 31. 140 –142.
Chand M 1997 Ph D Thesis CSA Univ of Agri Sci & Tech Kanpur
Das S K Sachan S S & Choudhary H P 1974 Ann Prog Rep Deptt Soil Cons & Water Mgt, CSA Univ of Agri Sci & Tech Kanpur
Gupta D K & Bhan Suraj 1997 Indian J Soil Cons 25 133
Gupta, R.S., Khybri, M.L. and Singh, B. 1963. Indian Forester, 89:128
Hadda M S & Arora Sanjay 2002 Souvenir 5th Punjab Science Congress TIET Patiala.
Hadda M S Arora Sanjay & Khera K L 2005 J Soil Wat Conserv India 4 101
Mannering, J.V., L.D. and Johnson, C.B. 1966. Soil Sci Soc. Amer. Proc., 30; 101
Miharas, X. 1951. National Inst. Of Agric. Sci. Tokyo, Japan . July p 49.
Reddy T Y & Reddi G H S 1995 Principles of Agronomy pp. 335
Sharma R A Upadhyay M S & Tomar R S 1985 J Indian Soc Soil Sci 33 387
Singh P & Verma R S 1995 Indian J Soil Cons 23 135
Table 1. Effect of contour cultivation on runoff and soil loss
Crop Method of cultivation
Runoff (% of rainfall)
Soil loss (t ha-1) Yield (t ha-1)
Sorghum Along the slope 52.0 14.1 1.60
Contour sowing 36.0 5.5 2.00
Maize Along the slope 46.8 17.0 1.98
Contour sowing 37.2 9.3 2.53
Das S K Sachan S S & Choudhary H P 1974
Table 2. Effect of ridge and furrow system on kharif crops in alluvial soil
Crop Yield (t ha-1) % increase over
controlControl
(Flat sowing)Ridge and furrow
Sorghum 1.36 2.01 47.8
Pearlmillet 1.26 2.18 73.0
Maize 1.17 1.41 20.5
Gupta D K & Bhan Suraj 1997
Table 3. Yield of soybean, loss of soil and nutrients under different land treatments
Treatments Rainfall causing runoff (mm)
Yield (kg ha-1)
Soil loss (kg ha-1)
N losses (kg ha-1)
Flat 717.3 262 1404 34.90
Broad bed and furrow 717.3 1333 1332 21.35
Broad bed and tied furrows 171.3 1510 717 27.89
Raised and sunken beds 171.3 1546 220 7.28
Anonymous 1994
Table 4. Runoff and soil loss reduction through various vegetative barriers
Vegetative barriers Runoff (mm ha-1)
Soil loss (t ha-1)
Control 215.6 7.5
Sesbania sesban 131.4 3.5
Leucaenea leucocephala 133.2 3.7
Cajanus cajan 143.3 4.1
Vetiveria zizanoides 127.0 3.5
Cenchrus ciliaris 140.1 4.0
Chand M 1997
Table 5. Effect of mulching on grain yield and water use efficiency (WUE) of crops
Crop Mulch treatment Grain yield(kg ha-1)
WUE(kg ha-1 mm)
Chickpea Control 1430 6.5
Soil mulch 1750 8.1
Straw mulch@6 t ha-1 1800 9.4
Wheat Control 1730 6.6
Soil mulch 1830 8.2
Straw mulch@6 t ha-1 1830 7.5
Sharma R A Upadhyay M S & Tomar R S 1985
Table 6: Effect of tillage and mode of mulch application on plant height (cm)
Mode of Mulch Application Tillage Tm Tc Mean
Mw 251 250 251
M1/3rd 245 245 246
Ms 243 241 242
Mv 222 212 211
Mo 222 195 208
Mean 237 226
Bhatt R and Khera K.L. (2004)
Table 7 Effect of haloding on weeds, soil moisture and crop yield
Item
Treatment
Control Haloding CD (0.5)
Weed population 36.0 12.8 11.3
Soil moisture, mm/180 cm 267 276 NS
Maize yield, kg/ha 2770 3130 130
Wheat yield, kg/ha 3590 3970 NS
Anonymous 1991