Chemical Composition of Major Ions in Rainwater

Abstract

The present study investigated the chemical composition of rainwater at Kabir nagar, Nari, Nagpur, Maharashtra, India. The rainwater samples were collected on event basis during June-July-August-2006 and were analyzed for pH, major anions Cl, NO(3), SO(4)) and cations (Ca, Mg, Na, K, NH4). The pH value varied from 6.0 to 7.3 (avg. 6.3 +/- 0.3) indicating alkaline nature of rainwater. The pH of the rainwater was found well above the reference pH (5.6), showing alkalinity during the monsoon season. The average and standard deviation of ionic composition was found to be 98.1 +/- 10.6 micro eql(-1). The total anions contribute 45.1% and cations 54.9%, respectively to rainwater. Neutralization factors (NF) followed a sequence of NF(Ca) > NF(Mg) > NF(NH4) with factors of 1.1, 0.38 and 0.15 indicating the crustal components are responsible for neutralization of anions. The average ratio of (NO(3) + Cl)/SO(4) observed as 1.1 indicates that nitric and hydrochloric acid influences the acidity of rainwater. The ratio of NH(4)/NO(3) and NH(4)/SO(4) was observed as 0.68 and 0.34 indicate that the possible compounds which may predominate in the atmosphere are NH(4)NO(3) and (NH(4))(2)SO(4). Ionic correlation was established to identify sources of origin. A good correlation was seen between Ca and Mg (r = 0.95); suggesting the common occurrence of these ions from crustal origin. Similarly, the acidic ions SO(4) and NO(3) correlated well (r = 0.60) indicating their origin from similar sources. Other relatively significant correlations were observed between Ca and SO4 (r = 0.92), Mg and SO(4) (r = 0.83), Ca and NO(3) (r = 0.09), Ca and Cl (r = 0.34) and Mg and Cl (r = 0.31), and Mg and NO(3) (r = 0.71). The observed rainwater ratio of Cl/Na (1.1) is closer to that of seawater ratio (1.16) indicates fractionation of sea-salt and modifications by non-marine constituents as the site is 834 km away from the sea coast. The nss-Ca contribution was observed as 95.7% suggesting their crustal origin whereas nss-Mg and nss-K shows their contribution as 87.9% and 83.2% indicating influence of soil sources. The nss-SO(4) contributed as 87.4% shows anthropogenic origin.

Quality of Water in the Road Drainage Systems in the Warsaw Agglomeration, Poland

“…At the remaining points, nitrates attain values lower than 1.4 mg NO 3 /L. The obtained values were within the nitrate concentrations published in foreign references (from 0.01 mg NO 3 /L to 15.00 mg NO 3 /L) [32][33][34].…”

Nature and Sources of Ionic Species in Precipitation across the Indo-Gangetic Plains, India

“…In addition to this, the studies of precipitation chemistry in South Asian region especially in India have been performed (Rao et al, 1992;Granat et al, 2002;Kulshrestha et al, 2003;Safai et al, 2004;Kulshrestha et al, 2005;Momin et al, 2005;Mouli et al, 2005;Tiwari et al, 2007;Rastogi and Sarin, 2007;Salve et al, 2008;Budhavant et al, 2009;Safai et al, 2010;Shukla and Sharma, 2010;Budhavant et al, 2011, Das et al, 2011Salve et al, 2011;Tiwari et al, 2011Tiwari et al, , 2012Budhavant et al, 2014; references therein). However, there have been no systematic, long-term measurements of rainwater chemistry have been made over Indgo Gangetic Plains (IGP) region to date (Satsangi et al, 1998a, b;Das et al, 2005;Singh et al, 2007a;Tiwari et al, 2007;Das et al, 2010;Shukla and Sharma, 2010;Das et al, 2011;Tiwari et al, 2012;references therein).…”

Carbon sequestration and its relation with some soil properties of East Kolkata Wetlands (a Ramsar Site): a spatio-temporal study using radial basis functions

“…2j). After the monsoon, the agricultural runoff and high rainfall (Salve et al 2008) may be increase the amount of NO 3 (Fig. 2k).…”