Prospects for rainfed agriculture in gullied and ravine catchments through soil and water conservation practices

Prospects for rainfed agriculture in gullied and ravine catchments through soil and water conservation practices

Journal of Arid Environments (1992) 23: 433-441 Prospects for rainfed agriculture in gullied and ravine catchments through soil and water conservatio...

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Journal of Arid Environments (1992) 23: 433-441

Prospects for rainfed agriculture in gullied and ravine catchments through soil and water conservation practices

L. S. Bhushan, R. C. Yadav, B. L. Singh, A. K. Tiwari, M. Singh, M. L. Gaur & Babu Ram*

* Central Soil and Water Conservation Research & Training Institute, Research Centre, Agra-28200S U.P., India (Received 13 December 1989, accepted 7 July 1991) Gully erosion is a world wide problem of semi-arid regions. Gulliesoccupy nearly four million hectare land in India. To combat the problem, many operational research projects on land and water catchment management have been started since 1983. Problems, strategies, work development and yield increases from gullied catchment area in semi-arid Hamirpur District, Uttar Pradesh are presented. For the in situ conservation of incident rainfall, contour bunds were made on lands with up to 3% slope. On multi-directional lands with 3-10% slope, bench terracing was done and a series of earth gully plugs were constructed in the drainageways to stabilize the gullies and to increase available water in the root zone. Water conservation practices in the deep alluvial soils (verti-strochrepts), by land terracing and levelling, resulting in a many-fold increase in yield. With adoption of improved agrotechniques on land so developed, it should be possible to produce an additional six tonnes of chickpea from 130 ha, and 3S tonnes of wheat from 102 ha, from the land that was under these crops before treatment. The study revealed that even partial treatment in the upper part of the catchment resulted in improved food security, which should encourage people participation in other environment improvement programmes.

Introduction

Soil erosion is a severe problem in the semi-arid regions of the world (Greenland, 1977). Gullies are the most advanced stage of soil erosion, depicting an ugly, degraded habitat. Gullies are found in almost every part of the world and are known by different names in different countries (Haigh, 1984). In India, the gully systems in the deep alluvial soils bordering the rivers are known as ravines, and are identified by association with the name of the river along which the gullies are situated. These gullied lands constitute the numerous small catchments along the rivers. There are about 4 m ha of land in India which are seriously gullied and ravined (Anonymous, 1985), of which the YamunaChambal ravine zone, situated in the states of Uttar Pradesh, Rajasthan and Madhya Pradesh, is the largest. Figure 1 shows a typical catchment landscape in the Yamuna ravine system. Surface flow, due to the high intensity of rain, flows over the undulating topography and initiates gully formation. The process is accelerated by over grazing, deforestation and improper management of land and crops. Near the river banks the 0140-1963/92/080433 + 09 $08'00

© 1992 Academic Press Limited

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L. S. BHUSHAN ET AL.

Figure 1. Typical ravine landscape. situation is further aggravated by the river back flow during high floods. The rate of soil loss from such catchments is enormous (Dhruvanarayana & Ram Babu, 1983). According to a rough estimate by Bali (1972), about 4 m tonnes of foodgrain are interlocked in the degraded ravine zone. Increasing population, industrialization and growing civilization has increased the demand for more foodgrain and raw materials, necessitating the development of ravine land into a production base. The management of gullies and ravine degraded habitats required development of both land and water resources. Sound land management permits the proper interaction between applied inputs and natural resources for the production of raw materials. With a view of developing gullied and ravine lands, the catchment management approach was applied to a typical Yamuna ravine system (Fig. 1). The approach to counteract soil erosion, the results obtained, and the lessons learnt are presented here, and may prove beneficial for those rehabilitating other degraded ravine lands under rainfed farming system. Basic resources The catchment - The study was undertaken on the Sheetalpur catchment (Fig. 2), located in Hamirpur (25°28'N and 79°5'E) and forms a part of the Yamuna-Chambal ravine system. The 571 ha catchment area drains into the Betwa river through the Rohin drain, the Betwa river joining the Yamuna river at Hamirpur. Nearly 30 percent of the catchment area has slopes of more than 7'5%, and on a further 30 percent the slope varied between 3 to 10%. An estimated 25 to 30 percent of the rainfall is lost from the catchment as runoff (Anonymous, 1983), and the estimated potential erosion was 65 tonnes/ha/year (Bhushan, 1990).

Soil- The soils in the catchment area are very deep alluvium (verti-strochrepts), and vary in colour, texture and water characteristics (Table 1). The sub-soil contains calcareous nodules, which are exposed by the continuous erosion. The red soils have poor water holding capacity, low organic carbon content and nutrients availability. They are also susceptible to surface crusting. Small pockets of black clay soils are also found, which become sticky when wet (Nitant et al., 1989). Climate - The area falls within the semi-arid climatic zone receiving an annual rainfall of

850 mm. Precipitation occurs during the north-east monsoon, which usually starts in the last week of June. About 85 percent of the annual rainfall is received in the three months of July, August and September. A late onset of the monsoon, a long gap during the monsoon

435

PROSPECTS FOR RAINFED AGRICULTURE

N

N Scale-I: 15000

Figure 2. Topographic features of Sheetalpur catchment project. =, Pucca Road; = =, Kachcha Road; 0 0, habitation; ~,contour elevation, m; --, catchment boundary; - , drainage.

Table 1. Soil physical characteristics of thecatchment

Soil type

Water holding capacity COlo)

Field capacity COlo)

Wilting point COlo)

Organic carbon content COlo)

Red soil Black soil

25'6 42'8

15'3 30'6

7'2 12'4

0'28 0'42

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L. S. BHUSHAN ET AL.

period, and an early withdrawal are common features. The poor distribution of rainfall during the growing period results in drought stress of varying magnitudes for most of the rainfed crops. Winter rains are not common and winter crops are grown on conserved soil moisture.

Criticalfactors - Extensive wastelands in the form of gullied, humocky waste and scrub lands with multi-directional slopes of eroded soils are the physical problem. The lack of irrigation facilities means that the farmers must depend on rainfed crops. Small farm size, scattered holdings, low risk-bearing capacity of farmers, ignorance about advancement in farm technology and non-availability of inputs on soft loans are other crucial problems of the region. Catchment management strategies On sloping lands, plant available soil moisture was identified as the most critical limiting factor for crop growth and productivity. In order to reduce the impact of moisture stress on crop performance, emphasis was laid on conservation and management of any incident rainfall. The strategies adopted were: improving plant available moisture and reducing the erosion hazard by such conservation measures as contour bunding, bench terracing and levelling of lands with up to 10% slopes. Stabilizing steep gradients and inducing in situ water storage in the sub-drainageways by gully plugs fitted with drop-inlet pipe-spillways. Rehabilitating 108 ha of land belonging to capability class VI and VII (non-cultivable land) through plantations of multipurpose trees and grasses, plus contour trenches and gully plugs. Educating by means of field demonstrations the socio-economically poor and poorly educated farmers about the value of non-monetary inputs such as seed rate, proper time and method of sowing, and low monetary inputs such as improved seed, fertilizer use, etc. involving Government agencies, namely Soil Conservation, Forest, Minor Irrigation, Rural Engineering and Animal Husbandry departments in long-term all round development. Developmental work

Land and water resources: The Soil Conservation Department of the Uttar Pradesh State Government undertook the execution of the physical work within the catchment area. Contour bunding was carried out on 28 ha land. Nearly 182 ha land was improved through

Figure 3. View of newly terraced land.

PROSPECTS FOR RAINFED AGRICULTURE

437

Figure 4. Gully plug in sub-drainageway.

gully plugs, and 52 ha by bench terracing and levelling (Fig. 3). Figure 4 presents a typical view of a gully plug in a sub-drainageway. Work in the catchment area was mainly land development for agriculture. Other works on water resources development and soil erosion control in the deep ravines remain incomplete.

Agriculture development: Three hundred and forty seven crop demonstrations during the past four years showed the value of non-monetary inputs, such as seed rate, time and method of sowing, etc. Parallel demonstrations with improved seeds were also introduced, with medium levels of fertilizer application. These were mainly to induce confidence in the poorer farmers and to demonstrate the usefulness of conservation measures and farm technologies for increasing productivity. About 21,000 trees were also planted under the social and agroforestry programme. Benefitcost ratio: The benefit from crop production and cost of development of catchment, computed at 10% per annum interest both sides, were Rs. 4'134 million and Rs. 1'625 million respectively. The overall benefit cost ratio from these figures worked out at 2'54, which indicates the economic viability of the project. Results and discussion

Land development and performance of crops: It was very convincingly demonstrated that land development measures adopted in the catchment area were very effective in boosting crop yields. From the yield data in Table 2 it is evident that the yield of guinea corn (Sorghum bicolor (L.) Moench) could be increased by nearly 2'5-fold following land development, improved seed and adequate fertilizer application, as compared to the control. Similarly, the yield of green gram (Vigna radiata (L.) Wilczek) could also be increased by about the same magnitude, and the yield of chickpea (Cicer arietinum L.) could be doubled, following bench terracing and levelling. Runoff between two gully plugs was only concentrated near the plugs and the larger part of the area did not benefit, in terms of residual moisture, from rainwater conservation. With contour bunding, runoff concentration was over a relatively larger area than with gully plugging. On bench terraced field, rain water was more uniformly distributed and higher crop yields were obtained over the entire area. However, the process of bench terracing involved cutting the top and back filling the bottom part of the slope. In ravine catchment, cutting of the upper one third of the slope produced enough soil to fill the lower

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Table 2. Effect of conservation measures onperformance of crops

Conservation measures

Guinea corn (1986-87)

Control without conservation measures Land developed through gully plugs Contour bunding Land developed levellingand terracing Adoption of improved varieties of seed and fertilizer on terrace fields * q (quintal)

Yield of crops (q* ha- 1 ) Green gram Chickpea (1986-87) (1986-87) (1987-88)

15

2'2

6'3

6'5

25

4'6

5'6

7'5

34

4'1

13'0 12'0

11'5 8'6

40

5'5

Wheat (1987-88) 10'5

36'5

11'6

= 100kg.

two-thirds and make level benches (Table 3). It was further observed that there was a considerably loss in yield due to the removal of top soil in the cut portion. Yield data in Table 3 further indicated that in the first year on the cut portion the yield of chickpea was 30-40 percent of that from the back fill portion. In the second year (1987-88), however, on the cut portion the yield was 66 percent of the back fill portion. The loss in yield was expected to be nominal in the third year. Nevertheless, inspite of the reduction in yield on the cut portion, bench terracing proved to be the most beneficial land treatment in increasing most crop yields by 200-300 percent (Table 2).

Agro-techniques and performance offieldcrop on terraced land Through a number of demonstrations on the farmers fields, the value of improved genotypes of different crops were shown (Fig. 5). The improved variety produced more than 100 percent increase in yield compared to crops grown under similar management with non-improved seed. Among the non-monetary inputs it could be demonstrated how important it is to sow the correct rate of seed and at the appropriate time. For late sown wheat, a 20 percent higher yield was obtained by using the criss-cross method of sowing.

Table 3. Response ofchickpea and wheatyield to land levelling

Year 1986-87 1986-87 1986-87 1987-88

Area(%) Cut Fill

Chickpea Variety Cut

Fill

Total

33 37 34

'C2351' 'C209' 'C209' 'C209'

15'5 12'8 13'5 10'5

12'0 10'7 10'5 9'2

1 q (quintal) = 100kg.

67 63 66

4'6 5'5 4'7 6'6

Variety

Wheat Cut

'WH 147'

6'6 21'3

Fill

10'5 32

PROSPECTS FOR RAINFED AGRICULTURE

439

35 30 I

o s: CT

-0 20 Q; ';;'

s o

c

-'

'0

C5

30

Crop varieties 35

c--------------. , .. ,'" -',,

'0s: 30 CT

-0

~

,

", Wheat

25

"-

20 I 5 L...-..L-_.L.-.--I_--...l.._--l.l 100 125 150 175 200 Seed role, Kg ha- I

45.--------,

40 I

l!

35

CT

!i

30

T

Q)

>=

15

25

o .c 10

20

~

15

>=

CT Q)

1-15 15-30 1-15 AFTER NOV NOV DEC 16, DEC

5 0 L...-..4-_..L-_..L-_U BEFORE 11-20 21-30 AFTER 10 NOV NOV NOV I, DEC

Sawing date

Figure 5. Effect of non-monetary and monetary input practices on crop yields.

The use of even moderate levels of fertilizer (IS kg N 40 kg P20sha-1), increased the yield of chickpea from 6 q to 12'5 q ha-1.

Sustainability ofproduction: Table 4 presents the yields of the major crops for the region grown in demonstration plots with moderate levels of monetary input practices compared to those grown outside the demonstration plots. For almost all crops yields from the demonstration plots were almost double of those grown outside. In spite of a very severe drought during 1987, the yields of chickpea, wheat and linseed under demonstration were considerably more than those outside and were comparable to yields obtained during a good rainfall year, such as 1988, thus indicating the stability of production due to catchment management.

Increased production: On the basis of demonstrations carried out with chickpea and wheat, it was shown that with medium levels of land management and other inputs, an additional production of 4'7 and 34'5 q ha- 1 of chickpea and wheat could be achieved on reclaimed ravine lands (Table 5). As a result, additional production of 611 q of chickpea and 3519 q of wheat could be possible from the same land area following land development. Thus, bench terracing of ravine lands can result in food security (Fig. 6) which is the prime concern of local people living in the region. Once this is achieved, people participation in future environmental programmes are more likely to accrue.

L. S. BHUSHAN ET AL.

440 1

Table 4. Yield (q ha- ) of different crops within thedemonstration plotand outside of thecachment programme Variety

Crop Guinea corn Green gram Sesamum Wheat Chickpea Pigeon pea Brasica-Mustard [Brassicajuncea (L.) Czern.] Toria [B. campestris (L.) var. ttoria Duthie] Linseed [Lium usitatissimum L. ] Lentil

CSH T-4 WH147 JG31S T-21 Varuna

1986-87 Demonstration Local 15'5 4'1 2'6 32'1 13'5 11'5

1987-88 Demonstration Outside

12'3 2'2 1'2 16'0 5'3 6'0

4'1

2'2

24'0 9'5

10'5 6'5

12'5

3'5

10'0

3'0

8'5

3'0

11'5

5'0

Note - Signifies that no demonstration was conducted on that crop.

Conclusion From the results obtained through a series of crop demonstrations it is shown that in ravine development programme, bench terracing and levelling with proper disposal of surplus water is the most beneficial among conservation programmes, such as gully plugging and contour bunding. Crop yields from reclaimed land can be increased significantly by adoption of non-monetary and low level of monetary input agro-techniques.

Lessons learnt (1) Even partial treatment of the upper portion of ravine catchments induces desired benefits and food security, thus facilitating acceptance of other measures relating to environment improvement programmes in the project area. (2) Gully plugging is not a suitable practice for agricultural land. However, it stabilizes gullies and augments soil moisture for plantations, etc. (3) Cost-intensive work in land development should follow a massive education programme with group discussions and demonstrations of nonmonetary or low monetary input practices, to induce participant eagerness in harnessing Table S. Increase in production of chickpea and wheat

Crop

Crop cultivation (ha)

Chickpea Wheat * I q (quintal)

130 102

= 100kg.

Yield levelsachieved (q * ha -1) Outside In demonstration demonstration plot 11 45

Production gap

Additional total production possible

q ha"

(q)

611 3519

PROSPECTS FOR RAINFED AGRICULTURE

441

Figure 6. A good crop of Sorghum in the catchment.

benefits from natural resources. (4) Catchment management is a way to reduce the adverse effects of drought. Authors are grateful to Dr Gurmel Singh, Director, CS & WCR & TI, Dehra Dun for his keen interest in the project. The authors record appreciation for Dr R. Babu and Dr G. Shastri, Principal Scientists for their involvement in preparation of project plan. The project was implemented by the State Soil conservation Department which is also acknowledged.

References Anonymous, (1983). Operational Research Project on Watershed Management, Sheetalpur, District Hamirpur (UP). CSWCRTI, Res. Centre, Agra (Mimiograph): 1-48. Anonymous, (1985). Statistics - Soil and Water Conservation: Watershed Management: Land resources-land-reclamation in India. Ministry of Agriculture and Rural Development, Department of Agriculture and Cooperation. Soil and Water Conservation Division, New Delhi. Bali, J. S. (1972). Ravine Reclamation Report of the working group on ravine reclamation, , Government oflndia, Ministry of Home Affairs, New Delhi, pp. 30-40. Bhushan, L. S. (1990). Watershed Management and Productivity. A report. University of Hawaii, U.S.A. (Mimiograph). Dhruvanarayana, V. V. and Ram Babu. (1983). Estimation of Soil Erosion in India. Journal of Irrigation and Drainage Engineering, 109: 419-434. Greenland, D. J. (1977). The magnitude and importance of the problem. In Greenland, D. J. and R. Lal (Ed.). Soil Conservation and Management in humid tropics. Chichester, John Wiley & Sons. pp. 3-7. Haigh, Martin J. (1984). Ravine erosion and reclamation in India. Geoforum 15: 543-561. Nitant, H. C., Bhushan, L. S. and Gawande, A. P. (1989). Implication of physicochemical properties in soil and water conservation practices of watershed (Hamirpur, U. P.). JournalofSoil and WaterConservation, India, 33: 31-38.