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Water logging
- 1. Today is OurPresentation Topic Name Is – Water Logging Mohammad Khasrul Alam. ID No. : 003-18-23. Department Of Civil Engineering. Southern University Bangladesh. Mohammad Sakil Ahamed. ID No. : 003-18-45. Department Of Civil Engineering. Southern University Bangladesh.
- 2. Index WATER LOGGING– WATERLOGGINGFIGURE– TYPES OF WATER LOGGING EFFECTS OF WATERLOGGING ON PLANT GROWTH – EFFECTS OF WATERLOGGING ON PLANT GROWTH FIGURE – MAJOR WATER LOGGED AREAS PREVENTION OF WATER LOGGING PROBLEMS DUE TO WATER LOGGING CAUSES OF WATER LOGGING CAUSES OF WATER LOGGING FIGURE MEASURES TO CONTROL WATER LOGGING MEASURES TO REDUCE IT LET'S SEE HOW THE RAIL TIES AND HOW TO MAKE DIFFERENT PARTS OF IT… END
- 3. WATER LOGGING - 1.The soil whose surface layers are saturated with water is called as waterlogged soil. 2.The phenomenon of rising of water table is known as waterlogging.
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- 5. TYPES OF WATERLOGGING 1)Water logging due to permanent submersion of land. Such as ponds, rivers, etc. 2)Water logging from periodical submersion such as coastal & estuarine land inundation by soil water or runoff of freshwater over lands etc. 3) Temporary water logging by stagnation of water as a result of heavy rainfall. 4)Water logging by coming out of water table to the surface & swampy areas in valleys are mostly caused by the phenomenon. 5)Water logging from artificial irrigation of agricultural lands in polders areas.
- 6. EFFECTS OF WATERLOGGING ON PLANT GROWTH Some important effects of waterlogging on plant growth are given below : i. The air in the soil pore is replaced by water ,leading to oxygen deficiency and hence reduce the plant growth. ii. In waterlogged soil transport of gases is reduced disturbing normal growth. iii. Limited exchange of gases increase amount of co2 which affect transpiration and water absorption. iv. In absence of oxygen, microbes produce toxis substances such as methane and effects growth of plants.
- 7. EFFECT OF WATERLOGGING ON PLANTS GROWTH v. In waterlogged soil major form of nitrogen is ammonia which is toxic to crops vi.Under waterlogged condition the concentration of phosphorus, iron, manganese, silicon increases and that of zn decreases. The increase in ferrous ion concentration is toxic to many crops.
- 8. EFFECTS OF WATERLOGGING ON PLANT GROWTH FIGURE -
- 9. MAJOR WATER LOGGEDAREAS - The chanal Beel in Natore. The Haor basin, the eastern part of Sylhet, Mymensingh & Moulovibazar. The Kaptai Lake in Chittagong. Riverine flood plains of Ganges, Brahmaputra, Meghna, Tista & other small rivers of the country. Haors, Beels, baors & other natural & artificial ponds. The coastal areas of Chittagong, Cox are Bazar, Noakhali, Patuakhali, Barisal & the Sunderbans.
- 10. PROBLEMS DUE TOWATER LOGGING - It creates anaerobic condition in soils for which microbial activity is hampered. The availability of nutrient elements in soil is reduced & leaching loss is higher. Increases soil pH in coastal & dry area which leads salinity & alkalinity. Pollutes soil water & favors excessive weed growth.
- 11. CAUSES OF WATERLOGGING - 1. Seepage of water from canal system The main cause of waterlogging in pakistan is seepage of water from network of canal system. 40 - 50% water is lost from main canals, seeps through soil and rised the ground water. In some cases the water table has risen upto root zones or even surface of soil. 2. Poor surface runoff and slow drainage The soil surface of pakistan is flat so surface runoff is poor and hence slow drainage, result in accumulation of water on soil surface and move to the water table under the influence of gravity. The water table has risen causes water logging
- 12. CAUSES OF WATERLOGGING - 3. Interruption of surface runoff. Construction of irrigation networks and housing colonies in the path of natural drains interrupted surface runoff, resulting in accumulation of water in rainy season contributes to waterlogging through seepage. 4. Rainfall. After heavy rainfall rain water percolates down the pores between soil particles under the action of gravity. 5. Floods. Flood water spreads on the surface of soil in plains. Due to inappropriate drainage system, this water percolates in soil and raise water table cause waterlogging.
- 13. CAUSES OF WATERLOGGING - 6. Poor water management Sometimes farmers use their land unscientifically. Excessive irrigation Lack of inadequate drainage system. 7. By breaking hardpan at a canal bed. During cleaning season ,the digging of canals breaks the hardpan of the soil at canal bed. It enhances the seepage of water. 8. Railway lines /Roads. The construction of railway lines and roads in food plains interrupted the passage of runoff water ,water collected in rainy season in the form of ponds, percolates to soil, Result in waterlogging.
- 14. CAUSES OF WATERLOGGING FIGURE -
- 15. MEASURES TO CONTROLWATER LOGGING - Providing efficient surface Drainage. Reducing percolation(the slow passage of a liquid through a filtering medium) from canals. Restriction of unwanted irrigation. Adoption of sprinkler method for irrigation Removing obstructions in natural drainage.
- 16. MEASURES TO REDUCEIT - Construction of dams & embankments along the coast to restrict saline to enter the agricultural lands. Could be an effective measure of reducing the water logging. Providing adequate number of bridges & culverts, along the roads, railroads, highways, across the canal etc could be a handy measure against water logging.
- 17. PREVENTION OF WATERLOGGING - 1.Reducing percolation from irrigation channels 2.Reducing percolation from water courses and fields 3.Encouraging economical use of water 4.Increasing outflow from the ground water reservoir
- 18. Let's see… Howto prevent water logging and crop failure during the floods
- 19. Thank You See youagain any other class and any other presentation. End