MART-AZR Project Research Report 78: Economics of Water-Harvesting Trials with Cereal Crops in Highland Balochistan

Abstract

As an attempt to demonstrate better utilization of rainwater in khushkaba agricultural systems, AZRI has been growing different crops under water­ harvesting techniques since 1986. The preparation of small catchment areas on rainfed valley bottom soils represents a low-cost method of generating run-off and increasing crop yields within the cropped areas. The proportions of water catchment area and cropped area investigated were as follows: for the control treatment the entire area is planted to the crop; in the 1:1 treatment one half of the area is used for water catchment and one half for planting; in the 2:1 treatment, two thirds of the area is used for water catchment and one third for planting. The objectives of this study were: i) to compare water-harvesting techniques with the existing farming practices and ii) to determine to what extent economic benefits are increased and their associated risks decreased. Data from six seasons of wheat trails, and four seasons of barley trails were used in this study. Partial budgets were developed for each crop, season, location and trial, to calculate net benefits and costs associated with the treatments. Results from wheat trials showed that the 1: 1 treatment had 22 percent higher net benefits (Rs 422/ha) than the control (Rs 34S/ha) with; a 22 percent reduction in the coefficient of variation. The 2: 1 treatment had 33 percent lower net benefits (Rs 230/ha) than the control and reduced the variation in net benefits by 10 percent. In contrast, barley trials showed that the 1:1 treatment yielded 18 percent lower net benefits (Rs 291/ha) than the control (Rs 421/ha) but increased by 6 percent the variation in net benefits. Treatment 2:1 had 14 percent lower net benefits (251 Rs/ha) than the control and 19 percent more variation. Even though gross revenues of wheat straw anu grain under the 1:1 treatment were lower than the control, the reduction in total costs under the 1:1 treatment resulted in higher net benefits than the control. Under conditions where land suitable for cultivation is limited, the increases in yields of both straw and grain in the cropped area resulting from water-harvesting has to be offset by the opportunity cost of the catchment area. Moreover, less than proportional decreases in total costs of the water-harvesting treatments as the catchment to cropped area changes can limit the economic performance of the technique. The data available for the analysis does not represent the entire spectrum of weather conditions in highland Balochistan; therefore, it is desirable to incorporate the probabilities of different quantities of rainfall into the economic analysis. Simulation techniques are suggested to generate probability distributions of net benefits of these cereal crops grown under water harvesting. The assessment of the adoption potential of these technologies will be facilitated by these simulations in conjunction with the quantification of farmers' perceptions of the benefits associated with water harvesting practices.