The north‐eastern region of India, although rich in land and water resources, often suffers from a water‐scarce situation particularly during the non‐rainy season. The steep terrain conditions do not support conventional irrigation systems and therefore micro‐irrigation system needs to be promoted. In micro‐irrigation systems, maintaining uniformity of application is necessary to achieve a satisfactory crop yield. Maintaining the system hydraulics is a challenge due to the terrain conditions and equipment available. A study was conducted to observe various uniformity parameters of selected emitters at five different operating pressures, viz. 0.5, 0.75, 1.0, 1.25 and 1.5 kg cm–2. In the study it was observed that the discharge variation of the selected emitters was between 8.7 and 39.7%. The uniformity coefficient varied from 0.9 to 16.6, where the distribution uniformity and statistical uniformity varied from 81.1 to 99.1% and 83.4–99.1% respectively. The emitter flow variation ranged from 0.03 to 0.49 in the range of 0.51.5 kg cm–2. The emitter exponent indicated that the values ranged from 0.20 to 0.55. All these values were far from the manufacturer's value. From the study we can interpret that the emitting system needs to be tested before adoption in the field to ensure uniformity of water application. Copyright © 2016 John Wiley & Sons, Ltd.

In this paper standardized precipitation index (SPI) is used to assess meteorological drought for all 30 districts covering 10 agro-climatic zones in an eastern Indian state, Odisha. Monthly rainfall data of 115 years (1901-2015) for all 30 districts of Odisha are analyzed using SPI on 1, 3, 6, 9 and 12-month timescale. These timescales reflect the impact of drought on the availability of different water resources. Results indicate that in all the agro-climatic zones of Odisha, mild drought events have the highest frequencies of occurrence followed by moderate drought events for different timescales. Severe and extreme drought frequencies are comparatively lesser than mild and moderate drought frequencies. SPI analysis shows that 32-46 years are affected by mild drought, 4-16 years affected by moderate drought, 1-9 years are affected by severe drought and 1-5 years are affected by extreme drought during study period of 115 years in different agro-climatic zones of Odisha. It is observed 50.3% areas in the state are affected by drought in June out of which chances of occurrence of mild drought is maximum (28.7%). In the months of July, August and September, 51.7, 48.5 and 46.1% areas are affected by droughts. On average 49.15% areas of the entire state is affected by drought of various intensities out of which the share of mild, moderate, severe and extreme drought is 28.38, 13.28, 5.06 and 2.43%, respectively.

In this paper, assessment of meteorological drought has been carried out by standardized precipitation index (SPI) for Western Central Table Land Agro-climatic Zone covering six districts of Odisha, India. Monthly rainfall data of 115 years for all the six districts of this agro-climatic zone of Odisha were analyzed using SPI on different time scales of 1, 3, 6, 9, and 12-month. Results indicate that mild drought events have the highest frequencies of occurrence followed by moderate drought events for all timescales under analysis in all the districts. The average total frequency of drought of all intensities are observed to be 54.10% out of which mild, moderate, severe and extreme drought will occur with frequencies of 35.5, 9.5, 6.25 and 2.85%, respectively. 49.25% areas of this agro-climatic zone in the state are affected by drought of various intensities out of which the share of mild, moderate, severe and extreme drought is 28.40, 13.28, 5.05 and 2.52%, respectively.

Three timescale i.e. monthly, seasonal and annual rainfall data of Bundelkhand region, Central India, was analyzed for 40 years (1981-2020).  The annual mean average rainfall for the region ranges between 657.7 mm and 1146.4 mm for the studied period with the month August receiving the highest amount of rainfall. The region receives about 90 % of its annual rainfall during South West Monsoon period i.e. from June to September. Temporal trend of rainfall for different timescale was analysed using nonparametric Mann-Kendall test and Sen’s slope estimator. Increasing and decreasing trend were found for the three timescale in which the study was carried out. Annual rainfall trend of Bundelkhand region is found to follow decreasing trend except for Sagar district. A decreasing South West Monsoon rainfall trend was also observed in 11 districts of Bundelkhand region.