RAMACHANDRA RAO, GNEERAJA, KOTHAKOTA2020-01-222020-01-222019http://krishikosh.egranth.ac.in/handle/1/5810141558D5770The present investigation entitled “Effect of Sewage water irrigation on Soil, Ground water and vegetable crops in peri-urban areas of Guntur district” was undertaken at the Department of Environmental Sciences, Advanced Post Graduate Centre, Guntur during 2018-19 to assess the impact of untreated sewage water on soil, water and vegetable crops. Four villages viz., Narakoduru, Vejendla, Chebrolu and Selapadu from the peri-urban areas of Guntur district were selected for the study. Sewage water used for irrigation was collected from the study area at monthly intervals for a period of six months (August, 2018 to January, 2019). Soil and ground water samples were collected twice (in the month of August, 2018 during pre-monsoon season and in the month of January, 2019 during post-monsoon season). Vegetable samples (Broad bean and Coccinia) were collected at the time of harvest. Physicochemical and chemical characteristics of the collected sewage water, soil, ground water and vegetable samples were analysed. The pH and Electrical Conductivity of untreated sewage water used for irrigation in peri- urban areas of Guntur district ranged from 7.57 to 8.01 and 0.80 to 1.73 dSm-1 respectively indicating that the sewage water is alkaline in nature. Carbonates were absent in the sewage water of four villages whereas bicarbonates, sulphates, chlorides, sodium, potassium, calcium and magnesium concentrations ranged from 4.7 to 8.4, 0.79 to 2.01, 4.00 to 8.40, 5.40 to 9.20, 0.57 to 1.91, 3.0 to 5.2 and 1.7 to 2.6 meq l-1 respectively. Sodium Adsorption Ratio and Residual Sodium Carbonate content in sewage water were in the range of 1.22 to 4.84 and -1.9 to 1.2 meq l-1 respectively. Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) in sewage water ranged from 194 to 341 mg l-1 and 343 to 548 mg l-1 respectively. The pH and Electrical Conductivity in soils irrigated with sewage water ranged from 7.59 to 8.04 and 0.72 to 1.36 dSm-1 during pre-monsoon season whereas from 7.89 to 8.4 and 1.07 to 1.44 dSm-1 during post-monsoon season respectively. Author : KOTHAKOTA NEERAJA Title of the thesis : EFFECT OF SEWAGE WATER IRRIGATION ON SOIL, GROUND WATER AND VEGETABLE CROPS IN PERI-URBAN AREAS OF GUNTUR DISTRICT Degree : MASTER OF SCIENCE IN AGRICULTURE Faculty : AGRICULTURE Discipline : ENVIRONMENTAL SCIENCES Major Advisor : Dr. G. RAMACHANDRA RAO University : ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY Year of submission : 2019 xviii The per cent organic carbon content of soil irrigated with sewage water ranged from 0.50 to 0.71% during pre monsoon season and 0.60 to 0.87% during post monsoon season. Available Nitrogen, Phosphorus, Potassium, Sulphur, Calcium and Magnesium were high in sewage irrigated soils than that of the check area. The DTPA extractable Zinc, Iron, Copper and Manganese content in sewage irrigated soils ranged from 0.42 to 1.09, 4.10 to 8.60, 1.57 to 5.24 and 1.76 to 4.95 mg l-1 respectively during pre-monsoon season and 0.54 to 1.52, 4.85 to 9.89, 2.99 to 6.47 and 2.49 to 5.61 mg l-1 respectively during post-monsoon season. The Cadmium, Chromium, Nickel and Lead content were higher in sewage irrigated soils than the check area. In fact, the concentration of the heavy metals increased during the study period (from pre to post monsoon season). The pH of ground water samples collected near sewage sites in four villages during pre-monsoon period ranged from 7.21 to 7.58 whereas 7.29 to 7.77 during postmonsoon period. The Electrical conductivity of ground water near sewage discharge sites during the pre-monsoon and post-monsoon season ranged from 0.28 to 0.82 dSm-1 and 0.36 to 0.85 dSm-1 respectively. There were no carbonates in ground water samples in all the four villages. The bicarbonate, sulphate, chloride, sodium, potassium, calcium and magnesium content in ground water near sewage discharge sites in four villages ranged from 2.3 to 4.5, 0.08 to 0.47, 2.2 to 5.1, 2.00 to 2.54, 0.03 to 0.26, 1.8 to 3.4 and 1.0 to 2.2 meq l-1 during pre-monsoon season and 3.2 to 5.3, 0.15 to 0.61, 2.5 to 5.4, 2.28 to 3.66, 0.1 to 0.4, 1.9 to 3.8 and 1.3 to 2.7 meq l-1 during post-monsoon season respectively. The increase in anions and cations in ground water near sewage sites was due to their addition through sewage water that contains high amount of the respective anions and cations. The Sodium Adsorption Ratio of ground water near sewage sites during pre-monsoon season ranged from 1.27 to 1.98 and during post-monsoon season, it ranged from 1.34 to 2.25. The RSC content in ground water near sewage sites during pre-monsoon season ranged from -2.4 to 0.9 meq l-1 and during post-monsoon season, it ranged from -2.1 to 1.3 meq l-1. The Biological Oxygen Demand and Chemical Oxygen Demand increased slightly from pre to post monsoon season. Total nitrogen, total phosphorus and total potassium, sulphur, calcium and magnesium content in vegetables irrigated with sewage water in four villages in peri- urban areas of Guntur district ranged from 0.63 to 1.19%, 0.09 to 0.17%, 0.30 to 0.45%, 0.15 to 0.51%, 0.07 to 0.18% and 0.18 to 0.30% respectively. The overall Zinc, Iron, Copper and Manganese content in vegetables irrigated with sewage water in the study area ranged from 21.62 to 45.28, 298 to 794, 29.16 to 39.54 and 1.01 to 2.60 mg l-1 respectively. The Cadmium, Chromium, Nickel and Lead content in the sewage irrigated vegetables ranged from 1.21 to 4.00, 1.49 to 4.77, 1.85 to 6.50 and 2.23 and 5.67 mg l-1 respectively. All the heavy metals except Chromium were above the permissible limits in vegetables for consumption. The increase in macronutrients, micronutrients and heavy metal content in the vegetable crops might be due to their translocation from the soils irrigated with untreated sewage water.en-USnullThesis