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Analysis of rainfall distribution and its changing pattern plays a vital role in managing water resources in a region. This work examined the spatio-temporal variability and trend of rainfall on yearly and season-wise scales during 1971–2013 in the Wainganga river basin situated in middle India. The Mann–Kendall (MK) test was implemented for identifying the temporal variation in rainfall trends. The magnitude of this changing trend was estimated by applying Sen's slope (SS) method. A paired sample t-test was also employed to appraise the statistical significance of changes in rainfall data. The results of MK and SS tests show both upward and downward trends. The results show positive and negative trends in the south-eastern and northwestern parts of the study area for annual rainfall. The monsoon rainfall also shows very close proximity with annual rainfall data trends. The t-test states that the observed changes in precipitation are statistically significant. After trend and pattern analysis, state-space models (SSMs) were used to predict rainfall for future scenarios. Four SSMs (single, double, and triple exponential, autoregressive integrated moving average (ARIMA)) were employed for rainfall prediction. The analysis shows that the ARIMA is best for rainfall prediction with architecture of (0,0,0) (2,1,0) and can be used in Wainganga River basin. [ABSTRACT FROM AUTHOR]

In recent years, diatom studies have been consisting of different approach i.e., taxonomic study, contamination history, paleoclimate etc. The significant study has been reported from the different part of the Indian Especially in India, from the last several decades the study on diatom shifted from taxonomical classification to palaeothermometry study using isotopic analysis. To know the present status and get the future direction it is very important to review the past studies which not only gives the ample information about the records available but also benefitting to get future direction. In the present review we present the comprehensive review on records available from three different geopolitical regions. The review on these three regions shows that most of the work Indian parts in past decades diatom is mostly used for taxonomical and pollution study. diatom diversity has not been examined in many Indian regions. direction towards palaeothermometry reconstruction using advance analytical techniques such as stable isotope and others. [ABSTRACT FROM AUTHOR]

Sedimentation in lakes occurs from the time of its formation and continues till the final deposition. The rate of sedimentation varies depending upon climate, geology, soil cover and relief. In the present study, an attempt has been made to investigate the distribution and variation of sedimentation rate in Indian lakes. For this purpose, Indian lakes are classified into three zones viz., North Indian lakes (NIL), Central Indian lakes (CIL), South Indian lakes (SIL) and 27 sampling points distributed throughout India has been considered among all three zones. Correlation of rate of sedimentation data with catchment area, surface area and lithology is done in order to understand the controlling factors, rainfall and temperature data are also taken into consideration to know the effect on the sedimentation rate. In all three zones, the highest precipitation observed 2488, 1800 and 4000 mm/yr in the Nainital lake, Chilika lake and Pookot lake, respectively and temperature fluctuations in the northern region of India is higher than the central and southern region. The results showed that the NIL have relatively higher sedimentation rate compared to the CIL and SIL due to slopy terrain, higher precipitation, temperature and lithological inconsistency in northern Indian region whereas all these factors are less effective in other two zones with a minor contribution from other independent factors. NIL have ~0.634-0.804 cm/yr and ~0.636-1.117 cm/yr more sedimentation rate than CIL and SIL, respectively. [ABSTRACT FROM AUTHOR]

B Correction to: Theoretical and Applied Climatology b https://doi.org/10.1007/s00704-022-04168-4 The affiliation of one of the authors (Pranaya Diwate) has been wrongly mentioned in the paper. Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. [Extracted from the article]

Groundwater is the main source of drinking in coastal areas and the gradually decline in its quality is a most important issues. The aim of present study is to assess the groundwater quality and its deterioration in coastal aquifer in Guhagar area of Ratnagiri District, Maharashtra (India) by examining the hydrogeochemical characteristics. A total 25 water samples were collected from three different zones from the study area viz. seawater, backwater and groundwater, apart from this one surface water sample during the winter season. Samples were analyzed for its physicochemical parameters (i.e., pH, EC, TDS, Ca2+, Mg2+, Na+, K+, Cl, SO42, CO32 and HCO3) and selective trace elements such as Cd and Pb. The majority of the observed chemical parameters of all groundwater samples are within the permissible limit of the BIS water quality standards except pH, potassium and lead while WQI values indicate that the water quality is very poor to unsuitable category. The Cd and Pb concentrations in seawater and backwater are observed beyond the permissible limits. Generally established plots such as USSL plots, Gibbs plot, Bivariate plots and molar ratios such as sodium/chloride and chloride/bicarbonate were used to identify the seawater intrusion into the coastal aquifers. The suitability of groundwater for irrigation was evaluated based on sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), Permeability index (PI), Corrosivity ratio, sodium percentage (Na %) suggests that the most of the groundwater is suitable for irrigat ion purposes. Seawater ingression, ionic ratios and difference in groundwater geochemistry during the high and low tides indicate that the moderate effect of seawater. [ABSTRACT FROM AUTHOR]

In the present study climatic and ecological changes in a two meter 210Pb-dated sediment core (1840-2011 AD) retrieved from the Renuka Lake, Northwest Himalaya were investigated using multiproxy approach, e.g., diatoms, Chysophycean Cyst (C.C), grain size, and elemental geochemistry. The core contained seven benthic (Navicula, Gomphonema, Cocconeis, Rhopalodia, Cymbella, Eunotia, and Mastogloia) and one planktonic (Aulacoseira) diatoms. It has been observed that the lake was not favourable for the growth of diatoms from 1840 to 1900 AD, probably due to low productivity or inability to preserve. The first appearance of the diatoms recorded from 1903 AD corresponds to an increase in the rainfall, whereas a drastic increase in diatoms and the C.C population is observed in 1940 AD, which coincides with "the great acceleration of the 1940s" when a rapid increase in temperature was recorded worldwide. The mean grain size and elemental geochemistry also support the response of diatoms. Aluminium ascended and reached its maxima (7.76%) in the core exhibiting high terrigenous input from the catchment. The mean grain size shows an increasing trend with an average of 13.34 µm during this period, which is slightly higher than the average value of the sediment of the core. A phase of increasing productivity after the 1940s up to 1972 AD is inferred from the expanded population of Aulicoseira favours warm water condition and eutrophic–mesotrophic lake condition. The recent decrease in the diatom population from 1972 to 2007 AD seems to be associated with the anthropogenic activity near the lake, such as the construction of retaining wall in the periphery of the lake that prevented the nutrient input to the lake from the catchment. The response of diatoms of the Renuka Lake to climatic changes during the 1930s and 1940s also correlates with the global records. This study explores the potential of diatoms as proxy indicators in the Himalayan lakes and response towards global warming-related climatic change after industrial growth. [ABSTRACT FROM AUTHOR]