Impact Assessment of Watershed Development Programme A Case Study of Itagi Sub Watershed

Transcription

1 Impact Assessment of Watershed Development Programme A Case Study of Itagi Sub Watershed BY Mr. Palakshappa K Assistant Professor Department of Civil Engineering & STJ Institute of Technology Ranebennur Dr. M. K. Nagaraj Assistant Professor Department of Applied Mechanics & Hydraulics N I T K Surathkal

2 Introduction Erratic and low rainfall, low fertility soils, poor infrastructure development, along with high population pressure with low literacy levels are some of the main causes of poverty in the semi arid tropics. High demographic pressure of one billion people in India and additional 519 million people are expected to be added by Furthermore 33% of the world s population mostly from developing countries including India will be affected by water scarcity by 2025.

3 Low productivity in dry lands and over exploitation of groundwater for irrigation has emerged as major problems in semi arid tropics (SAT) in India. WDP is implemented for in situ moisture conservation to improve productivity of dry land through judicious use of soil and water, agronomic practices, dry land horticulture, forestry, and other soil and water conservation measures. These result in restoration of ecological balance and improve the socio economic conditions of dry land farmers.

4 Watershed Development Programme (WDP) The Government of India (GOI) and state governments have adopted watershed management as a strategy to address the sustainable agricultural productivity in the rainfed areas since the last three decades. Further GOI has adopted watershed management as a national a policy since 2003 (Joshi et al. 2004). In the present study effect of rainwater harvesting structures on groundwater recharge and impact assessment of watershed development programme of Itagi sub watershed dis tk taken.

5 Study Area

6 The total area of watershed is 4636 hectares covering six villages viz. Magod (16.33%), Itagi (24.78%), Kamdodu (19.91%), Devagondanakatte (14.43%), Manakur (9.19%) and Mustur (15.36%). As per agriculture region and zones of Karnataka it is the northern transitional zone and soil type is shallow to medium black clay and red sandy loams.

7 The depth of the soil varies from 1.0 to 1.5 metres. The land slope varies 1-4 percent. Rainfed agriculture is the major economic activity of this area. Important crops grown here are maize, jowar, bajra, small millets, cotton, pulses, groundnut, and vegetables. The area receives an average annual rainfall of 683 mm. The maximum and minimum temperature of the area is 20 0 C and 38 0 C respectively.

8 Socio-economically farmers of the watershed area have poor economic base. The average land holding is 1.86 ha and it has to support on an average of six family members.

9 Soil and water conservation structures Soil and water conservation practices very rightly receive top priority for planning watershed management as they form the foundation for the sustainable agriculture. Water resource development stimulates all further developments in the watershed.

10 Watershed Action Plan for Itagi sub watershed (Details of soil and water conservation Structures) t Sl. No. Activity Physical Unit Financial Rs.(Lakhs) 1 Private Land Volume of Water storage (m 3 ) Contour Bund 1170 Hectares Recharge Pits 11 No Farm Ponds 131 No Loose Boulder Checks 138 No Ravine 34 No Reclamation Structures

11 Check Dam 10 No Earthen Checks 1 No Rubble Checks 342 No Farm Forestry Hectares Horticulture Hectares Land Leveling Hectares Vegetative Bunds Hectares Waterways 112 Cubic.m Diversion Channel 2757 Cubic.m

12 2 Common Land Black Plantation Hectares Farm Ponds 1 No RRS R.R.S 4 No Desilting of Tanks 4 No Check Dams 36 No Nala Stabilization 15.6 Cubic.m Farm Forestry 0.49 Hectares Road Side 14 Hectares Plantation School Garden 0.5 Hectares Administrative Cost Total

13 Results and Discussions. To study the impact of the watershed development programme (WDP) the data regarding, crops grown cultivation area of different crops, cropping pattern, productivity of crops etc., before and after the watershed development programme in kharif, rabi and summer season, were collected and analyzed.

14 Since rainfall is main source of water to the crops and as it varies over the years, the data of three years 2001, 2002 & 2003 are averaged and are taken and analyzed for pre-project period (i.e., before the watershed development) and the averages of the data of the years 2005, 2006 & 2007 are used to analyze the post-project p period (i.e., after implementation of watershed development). elopment)

15 Impact on Crop Area (Kharif Season) rea (ha) Ar Maize Jow ar (Hybrid) Groundnut Onion Garlic Sunflow er Cotton (Jayadhar a) Vegetable Pulses Sericultur e Total Pre-project Post - project Kharif Crops

16 Impact on Crop Area (Rabi Season) Area (ha) Jowar(Rabi) Cotton (Niranjana)Gram Seteria Safflower Vegetable Pulses Total Pre- project Post-project Rabi Crops

17 Impact on Crop Area (Summer Season) Area (ha) Vegetable Maize Groundnut Watermelon Total Pre-project Post-project Summer Crops

18 Impact on Productivity( Kharif Season) Pro oductivity (q/ha) Maize Jow ar (Hybrid) Groundnu t Onion Garlic Sunflowe r Cotton (Jayadhar a) Vegetable Pulses Sericultur e Pre-project Post-project Crops

19 Impact on Productivity (Rabi Season) ctivity (q/ha) Produc Jowar(Rabi) Cotton (Niranjana) Gram Seteria Safflower Vegetable Pulses Pre-project Post-project Rabi Crops

20 Impact on Productivity (Summer Season) Produ uctivity (q/ha) Vegetable Maize Groundnut Watermelon Pre-project Post-project Summer Crops

21 Crop Diversification A significant diversity of crops takes place as a result of availability of more water. Crop diversification over a period of time is measured using the Hirschman-Herfindahl diversification index. The diversification index can be calculated as given below. DIV = 1-HHI Where HHI is Hirschman-Herfindahl Index and is given by HHI= [Pit/ Pit] 2 Pit being the value of production at 2007 prices of the i-th crop in that year

22 Diversity it Index (Kharif Season) Div 0.97 Pre-project Post-project Mi Maize Jowar Cotton Groundnut Onion Garlic Sunflower (Hybrid) (Jayadhara) Vegetable Pulses Sericulture Pre-project Post-project Kharif Crops

23 Diversity it Index (Rabi Season) DIV Jowar(L) Cotton (Niranjana) Gram Seteria Safflower Vegetable Pulses Pre-project Post-project Rabi Crops

24 Diversity it Index (Summer Season) DIV Vegetable Maize Groundnut Watermelon Pre-project Post-project Summer Crops

25 Cost of production and benefits Gross retur ns Returns over TC Benefit cost ratio (BCR Value Fixed cost Variable cost Total cost Productivity (Rs./ (Rs./ (Rs./ (Rs./ (Rs./ Crops (q/ha) Rs../q ha) ha) ha) ha) ha) ) Pre project Maize Jowar Groundnut Onion Garlic Sunflower Cotton Vegetable Pulses Sericulture (Silkworm)

26 Post project Maize Jowar Groundnut Onion Garlic Sunflower Cotton Vegetable Pulses Sericulture (Silkworm)

27 Change in B-C Ratio Values o BC Rati Maize Jow ar Groundnut Onion Garlic Sunflow er Cotton Vegetable Pulses Sericulture Pre- Project Post-project Crops

28 Improvement in the Groundwater recharge The natural groundwater recharge in the study area is about 9.82 percent After the WDP the groundwater recharge is estimated by monitoring i of the water levelsl in the wells located on upstream, middle stream and downstream of the watershed. It is found that groundwater recharge on the upstream, middle stream and downstream areas of the watershed are 14.31%, 17.28% and 20.21% respectively

29 The average improvement in the discharge is found to be and percent in the upstream area of watershed for the years 2006 and 2007 over the year Similarly for the middle stream and downstream area itis35.10and48.80percent,and41.43and53.10 percent respectively

30 People s perceptions A set of questionnaires have been prepared and the sample households were asked about what they felt about the watershed development programme. As may be seen, from all the 8 micro watersheds of the study area in each of the micro watersheds, a minimum of 10% of the total households representing various socio-economic and user groups (marginal, small, medium and large farmers) are covered.

31 Conclusions. From the above results it is clear that, the watershed development programme in Itagi sub watershed are has following benefits. The land and water conservation activities have significantly improved the soil moisture conservation and thereby improving the crop productivity in all micro watersheds.

32 Soil erosion has considerably reduced (visibly) and percolation perceivably increased in arable lands as contour bunds have been taken up extensively in these areas. Improved groundwater recharge and yield of the wells brought more area under irrigation. Changes in the cropping pattern. Increase in the benefits cost ratio in the cultivation of crops.

33 Improvement in socio-economic condition of the people in watershed. The watershed development programme has a significant positive impact on creation of employment opportunities for the villagers, both landless as well as landowners Awareness among people and active people s participation in the programme.

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