Management of problem soils and waters

I. Introduction Several million hectares of land are being suffering from one or other kind of problem and overall productivity is declining because of soil exhaustion Degradation of soil owing to misuse or abuse hampering the agriculture in one way or another. India needs to produce 310 m tones of food grains by 2050 to feed the projected population of about 1.5 billion. One of the options to achieve the target food production is by overcoming the limitations/problems of the soils by adopting suitable management practices. The limitations of soil may be of physical or chemical or biological in nature

Introduction contd… Physical- surface crusting, shallow depth, gravelly, slopy, compactness very low /high permeability, presence of subsurface hard pans etc. Chemical- acidity or alkalinity/sodicity, calcareous, presence of toxic elements, non availability of nutrients etc., Biological- absence of some useful soil micro-organisms or presence of harmful fungi/bacteria, absence of other biological agents including earthworms, weed infections etc., With the expansion of irrigation facility to newer areas through canals and over exploitation of ground water, salinity and drainage problems are on the rise. Hence this course deals with such soil problems and management of poor quality water.

Introduction contd … Some these soil problems might have arise naturally during formation of soils itself (Natural occurrence) or developed in course of time due to mans interference Faulty agronomic practices Unscientific irrigation practices Indiscriminative use of agricultural chemicals Improper drainage etc. As a professional soil scientist, one need to address these problems,diagnose visually at field level, characterize and assess the intensity of the problem by careful analysis in the laboratory and suggest remedial measures

II. Expectations about the course

1 & 2Problem soils – Importance of the course, course outlines – Exam pattern – P course evaluation – Definition – different types of problematic soils – Extent and distribution of problematic soils in India and Andhra Pradesh. Basic concepts of problematic soils – Factors responsible for the origin of the problematic soils 3 & 4Salt affected soils – Origin – History and nomenclature – Distribution of salt affected soils in India and Andhra Pradesh. Morphological features of saline, sodic and saline – sodic soils – Characterization of salt affect soils – Diagnostic criteria adopted for characterization 5 & 6Formation of salt affected soils – Causes – Sources of soluble salts – Field and laboratory diagnosis. Effect of salainity on plant growth – Buildup of soil salinity. Determination of average root zone salinity 7 & 8Reclamations of saltine soils – Leaching requirement – Agronomic and other manage meant options to overcomes salinity – Tolerance of crops and varieties to salinity – Mechanism of salt tolerance III. LECTURE OUT LINES

9 & 10Alkali soils – Causes for formation of alkali soils – Effects of alkalinity on plant growth. Reclamation of alkali soils – Chemical amendments – Gypsum requirement. 11 & 12Agronomic measures to overcome alkalinity – Relative crop tolerance to soil sodicity. Physical and hydro technical and bioameleoration measures for reclamation alkali soils. 13Management of saline – Sodic soils 14 & 15Acid soils – Extent of area in India and Andhra Pradesh, characteristic of acid soils – Causes of soil acidity 16 & 17Effects of acidity on plant growth – Reclamation of acid soils – Lime requirement of acid soils – Different liming materials used in acid soils reclamation – Benefits of liming – Harmful effects of over liming 18Management of acid soils – Method and time of application of liming material – Classification and acid tolerant crops 19 & 20Calcareous soils – Formation, causes, characteristics, management of calcareous soils and impact on plant growth LECTURE OUT LINES contd…

21Soil physical problems and management 22Management of sandy soils 23Management of clayey soils 24Management of red latertic soils 25Management of dryland rainfed soils 26Ill drained soils – Management practices 27Biological sickness of soils and its management 28 & 29Criteria of suitability of water for irrigation classification of irrigation water based on USDA – Use of poor quality irrigation water – Management – tolerant crops 30 & 31Characterization of brackish water – Extent and area of brackish water in India – Management of brackish water 32Cropping pattern for utilizing poor quality ground water LECTURE OUT LINES contd…

Suggested Readings 1.Bear. Firman E: (1964, Chemistry of soils) Oxford IBH 2.Jurinak JJ: (1978) Salt affected soils, Department of Soil Sci. & Biometrology, Utah Univ. 3.USDA Hand book No 60 (1954): Diagnosis and improvement of saline and alkali soils 4.Agarwal R. R, Yadav J.S.P & Gupta R.N Saline and alkali soils of India I C A R,New Delhi 5.Prasada rao,A and Bhupalraj, G (2001) Guidelines for soil based technologies to optimize land productivity in Andhra Pradesh, ANGRAU,Hyderabad

IV. Assessment- Examination pattern Theory Assignments,class seminars and quizes : 20 marks Mid term exam : 30 marks Final exam : 50 marks __________ Total : 100 marks Practical Lab work & record : 25 marks Practical written test : 20 marks Viva : 5 marks __________ Total : 50 marks Theory and practical marks put together(total 150) will be reduced to 100 and grade point will be awarded finally.

V. Pre -course evaluation Objective type test