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0.61 mm per year (at Malsiras) to 2.76 mm per year (at Bhor station). Bhor station (0.28%) showed the maxi-mum increase in percentage change in annual rainfall over the 104 years period. In case of season, monsoon and post monsoon seasons have rising trend whereas falling trend observed for summer and winter seasons. The magnitude of trend in monsoon rainfall varied between −0.18 mm/year (Akluj) to 2.26 mm/year (Bhor). For summer series, the decrease in magnitude varied from 0.09 mm/year (Bhor) to 1.03 mm/year (Akluj station). The decrease in percentage change varied between 0.22% (Bhor) to 1.31% (Akluj) in summer season. Changes in seasonal series depending on the time of year are shown in (Figures 4-7). There is an increase in the variability in post-monsoon since 1967 and less variability in summer at Akluj station. Bhor and Malsiras show variability only in monsoon season. The t-test statistics (Table 4) indicated that annual, monsoon, post- monsoon and summer rainfall trends in Nira basin to be significant at 10% levels. Hydrology of the basin and agriculture will influence by variability of post-monsoon as it contributes major share of annual rainfall. For basin wide global annual and seasonal trend statement was obtained using MK/MMK statistics at 10% significance level (Table 5). From table, the null hypothesis is accepted for annual and seasonal trend as 2homogχwas less than critical value at 10% significance level. That means the four stations have homogeneous trend over a Nira basin. In the context of global climate change, basin has variation in the rainfall pattern. Decreasing tendency in the summer monsoon rainfall, increasing trend has been reported in the rainfall during pre-monsoon and post-mon- soon months over Indian landmass . The increasing trend was found in the monsoon precipitation along the west coast, north Andhra Pradesh and north-west India and decreasing trend over east Madhya Pradesh and ad-joining areas, north-east India and parts of Gujarat and Kerala over 114 (1871-1984) years . 4.2. Application of Wavelet Analysis on Annual Rainfall Series Wavelet analysis is used to verify the trends in the series. The intensity of energy distribution of different time
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