Parallel Session 2: Economic Feasibility
WHERE TO GO? A SOCIO-ECONOMIC ANALYSIS OF SMALLHOLDER IRRIGATION FARMING IN SOUTH AFRICA'S NORTHERN PROVINCE
B HEDDEN-DUNKHORST1 and R E MPHAHLELE1
1University of the North, Dept of Agricultural Economics, P O Bag X1106, Sovenga, 0727 South Africa
The study aims to contribution to the discussion on smallholder irrigation farming in South Africa. Based on a socio-economic investigation of two irrigation projects in the Northern Province, it is shown that smallholder irrigation can contribute substantially to income and employment generation in rural households. Thereby crop choice plays and important role. Gross margins for alternative crops suggest that high value crops (e.g. vegetables) can compensate for small plots. An econometric model indicates inefficiencies of the existing support services. Recommendations suggest: 1) stronger emphasis on high value, labour intensive crops, 2) more appropriate extension advice in production, m anagement and marketing, and 3) better access to credit facilities.
EVALUATION OF COMBINED MICRO AND SURFACE IRRIGATION SYSTEMS IN SWEET LIME INTER-CROPPING
M V MANJUNATHA1, K N SHUKLA2 and H S CHAUHAN3
1Assistant Professor, Agriculture Research Station, Gangavati-583 227, Karnataka (India)
2Professor and 3AICTE Emeritus, Dept of Irrigation & Drainage Engineering, GBPUAT, Pantnagar, UP (India)
Field experiments were conducted to study the performance of microsprinkler and other irrigation systems in sweet lime inter-cropping at GBPUAT, Pantnagar, India during 1996-98. The studies showed a net increase in yield 27.3 per cent for cowpea and 25.14 per cent for potato crop while using microsprinkler irrigation as compared to surface irrigation method. The saving of water achieved through microsprinkler irrigation was of 26 and 37 per cent, respectively for cowpea and potato as compared to surface irrigation. The yield realized in okra for vegetable purpose was 232 q/ha. Significant increase in yields of sweet lime over surface irrigation was 79.6, 57.1 and 14.3 per cent for microsprinkler + drip, microsprinkler and surface + drip irrigation respectively. The saving of water achieved over surface irrigation was maximum in case of microsprinkler + drip irrigation (28.14%) followed by microsprinkler irrigation (19.94%) and minimum for surface + drip irrigation (4.11%). Substantial saving of water (> 31 times) was achieved by irrigating the sweet lime through drippers instead of microsprinklers during lean and gap periods of inter-crops. During the first year of planting, the highest net income was registered in case of microsprinkler + drip irrigation (Rs.79,920 per hectare) for sweet lime with inter-cropping followed by Rs.78,780, Rs.52,710 and Rs.61,710 per hectare for microsprinkler, surface + drip and surface irrigation, respectively as compared to Rs.-26,700, Rs.-27,840, Rs.-27,180 and Rs.-18,190 per hectare in case of sweet lime without inter-cropping. Due to inter-cropping in sweet lime, the net profit achieved per cm of irrigation water applied was Rs.2270, Rs.1940, Rs.1110 and Rs.1220 for microsprinkler + drip, microsprinkler, surface + drip and surface irrigation, respectively as compared with Rs.-760, Rs.-680, Rs.-570 and Rs.-360 for sweet lime without inter-cropping. Similar results were also observed during the second, third and fourth years of planting.
MORE CROP PER DROP: CONSIDERATIONS FOR PRECISION IRRIGATION IN A BASIN CONTEXT
H SALLY, R SAKTHIVADIVEL AND D MOLDEN
Irrigation and Water Resources Program of the International Water Management Institute (IWMI), P O Box 2075, Colombo, Sri Lanka
Improving the productivity of water in agriculture is of vital importance in meeting the world's food requirements in the context of increasing populations and growing scarcity and competition for water resources. One way of achieving this is by adopting irrigation techniques that keep non-beneficial evaporation to a minimum, enable better control of water applications and reduce the amount of water that needs to be diverted from the source. Such 'precision irrigation' approaches have immense potential for increasing productivity and sustainability when applied judiciously to suit the particular water management (or hydronomic) environment of a river basin. This paper deals with issues related to the adoption of precision irrigation in a basin context. In defining precision irrigation, a distinction is drawn between precision technologies and water management practices. The paper then examines situations where precision irrigation can be effectively applied in a water basin to improve water productivity and sustainability, including supplemental irrigation in water-stressed areas. Potential benefits of precision irrigation to resource-poor small farmers are also discussed, highlighting constraints and opportunities related to the large-scale adoption of such techniques.
OPTIMAL IRRIGATION SCHEDULING OF DRIPPER SYSTEM IN THE RAINFED AREA
S H PARK1 and H W JUNG2
1Head of Hydraulic Laboratory, Rural Research Institute, Korea Agricultural and Rural Infrastructure Corporation, 1037-1 Sadong, Ansan City, South Korea 425-822,
2Professor, Department of Agricultural Engineering, Seoul National University, Korea
An optimal irrigation scheduling model is derived for the dripper system of various crops including red pepper, bean and Chinese cabbage, which are main crops in Korea. The study aims to maximize irrigation benefit, crop yields and water usage in the field. In the experimental field, Irrigation water was supplied from the Drip irrigator connected to the ground water pump. A rainout shelter was installed to prevent the unexpected rainfall in the weighing lysimeter plot. To assess the irrigation benefit, market price of each crops and irrigation cost were studied.
As the results, root zone extraction pattern in each soil layer has been derived for various crop stages. A daily-based soil moisture budget model is developed to maintain optimal soil moisture level and maximize crop yields in the irrigated field. From the model, effective rainfall has been estimated to derive the overall consumed ratio at each of cropping stage. In spite of increase of crop yields and necessity of less irrigation labor for water supply, the irrigation benefits are rather low to compensate the installation and maintenance cost of the dripper system for common crops in humid area. It is concluded that dripper system is applicable for the crop that has high market price or where water resource is scarce.
THE ECONOMIST'S ROLE IN AN INTER-DISCIPLINARY, INTER-AGENCY MIP
Paul N Wilson
Department of Agricultural and Resource Economics
The University of Arizona, Tucson, Arizona, U.S.A.
Tel +1 520 621 6258; fax +1 520 621 6250; e-mail firstname.lastname@example.org
A Management Improvement Program (MIP) is a managed change process with the goal of improving the performance of an irrigation delivery system. With its theoretical roots in organizational development, the MIP process has been applied to irrigation projects in Latin America, Asia, and Africa. The first application of the MIP in the United States occurred in the Maricopa-Stanfield Irrigation and Drainage District (MSIDD) in central Arizona in the early 1990s. The roles of an economist and economic analysis within the general MIP framework are evaluated in this presentation. Emphasis is placed on the value of farm-level and district-level understanding for public policy analysis. Special attention is given to the rewards and frustrations of the only economist on a nine-person research team.
For further information, explore the following references:
WILSON PN (1997) Economic discovery in federally supported irrigation districts: A tribute to William E. Martin and friends. Journal of Agricultural and Resource Economics 22(1):61-77.
Entire issue of Irrigation and Drainage Systems, Volume 14, Numbers 1-2, May 2000.
This journal is available electronically via http://www.kluweronline.nl.