African Journal of Chemistry ISSN: 4391-3199 Vol. 3 (4), pp. 197-206, April, 2016. © International Scholars Journals
Full Length Research Paper
Irrigation impacts on the chemistry of soils in the study area
Vijay Khan Amitab
Post Graduate Department of Chemistry, Sangamner Nagarpalika Arts, D.J. Malpani Commerce and B.N. Sarda Science College, Sangamner – 422 605, Dist. Ahmednagar, (M.S.), India.
E-mail: [email protected]
Accepted 29 March, 2016
Abstract
Irrigation plays an important role in the present agriculture scenario. It is a major source which helps millions of rural poor in the world to earn their livelihood. Unplanned and unscientific use of both water and soil resources have led to severe deterioration. As a result of this, a greater threat is being posed to social, economic and political stability of many developing countries including India. Introduction of large scale irrigation, excess use of chemical fertilizers and pesticides, deforestation and over grazing, leads to accelerated soil degradation. In view of this, Sangamner area of Ahmednagar district, India is selected to study the impact of irrigation on the chemistry of soils. The soil samples were collected from 62 locations covering the entire study area. The samples were analyzed for PH, EC, Ca2+, Mg2+, Na+, K+, Cl-, HCO3-, and SO42- from saturation extract. The exchangable cations like Na+, K+, Ca2+ and Mg2+ were determined by neutral ammonium acetate extract. pH ranged from 8 to 9.7 reflecting alkaline nature of soils. Higher EC in the downstream part reflects low flushing rate and sluggish groundwater movement in the area. The concentration of soluble cations are in the order Na+>Ca2+>Mg 2+>K+, whereas Cl- is predominant followed by SO42- and HCO3- in the soluble anions. Out of the total exchangeable cations, Ca2+ is dominating over the rest of the cations. Salinisation, sodiumization, waterlogging, nitrate pollution and boron toxicity have been identified as the possible impacts of irrigation on the chemistry of soils in the area. The soils from the study area are easily waterlogged during the rainy season. The problem is further aggravated due to decrease in depth of water table by injudicious irrigation and canal seepage. There is an urgent need to focus attention on the protection of soils particularly in the irrigation sector. Frequent awareness and training programs for farmers can be arranged to avoid further degradation of soils.
Key words: Soluble cations and anions, sodium absorption ratio (SAR), exchangeable cations, exchangeable sodium percentage (ESP), boron toxicity
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Author(s) retain the copyright of this article.
Full Length Research Paper
Irrigation impacts on the chemistry of soils in the study area
Vijay Khan Amitab
Post Graduate Department of Chemistry, Sangamner Nagarpalika Arts, D.J. Malpani Commerce and B.N. Sarda Science College, Sangamner – 422 605, Dist. Ahmednagar, (M.S.), India. E-mail: [email protected].
Accepted 29 March, 2016
Irrigation plays an important role in the present agriculture scenario. It is a major source which helps millions of rural poor in the world to earn their livelihood. Unplanned and unscientific use of both water and soil resources have led to severe deterioration. As a result of this, a greater threat is being posed to social, economic and political stability of many developing countries including India. Introduction of large scale irrigation, excess use of chemical fertilizers and pesticides, deforestation and over grazing, leads to accelerated soil degradation. In view of this, Sangamner area of Ahmednagar district, India is selected to study the impact of irrigation on the chemistry of soils. The soil samples were collected from 62 locations covering the entire study area. The samples were analyzed for PH, EC, Ca2+, Mg2+, Na+, K+, Cl-, HCO3-, and SO42- from saturation extract. The exchangable cations like Na+, K+, Ca2+ and Mg2+ were determined by neutral ammonium acetate extract. pH ranged from 8 to 9.7 reflecting alkaline nature of soils. Higher EC in the downstream part reflects low flushing rate and sluggish groundwater movement in the area. The concentration of soluble cations are in the order Na+>Ca2+>Mg 2+>K+, whereas Cl- is predominant followed by SO42- and HCO3- in the soluble anions. Out of the total exchangeable cations, Ca2+ is dominating over the rest of the cations. Salinisation, sodiumization, waterlogging, nitrate pollution and boron toxicity have been identified as the possible impacts of irrigation on the chemistry of soils in the area. The soils from the study area are easily waterlogged during the rainy season. The problem is further aggravated due to decrease in depth of water table by injudicious irrigation and canal seepage. There is an urgent need to focus attention on the protection of soils particularly in the irrigation sector. Frequent awareness and training programs for farmers can be arranged to avoid further degradation of soils.
Key words: Soluble cations and anions, sodium absorption ratio (SAR), exchangeable cations, exchangeable sodium percentage (ESP), boron toxicity