ASSESSMENT OF IRRIGATION REQUIREMENT OF NARMADA COMMAND USING SOIL-CROP-CLIMATE DATA

Simple item page
dc.contributor.advisorPATEL, G. R.
dc.contributor.authorGIRI, JAYANT DATTATRAYA
dc.date.accessioned2018-06-05T06:17:17Z
dc.date.available2018-06-05T06:17:17Z
dc.date.issued1997
dc.description.abstractThe assessment of irrigation requirement of Narmada Command covering an area of 18 lakh hectares (1.8m ha) has been carried out using data on soil available water capacity and evapotranspiration data on crops viz., pearl millet, groundnut, pigeonpea, cotton, castor, mustard and wheat. The crop evapotranspiration (ETc) is computed using crop coefficient values (Kc). While ETc has been found to be mainly dependent on the climatic component, the Net Irrigation Requirement (NIR) has been found to depend on climate mainly effective rainfall and the soil available water capacity (AWC). Differences between the Crop Water Requirement (CWR) and NIR were wide for the monsoon season, but narrowed down considerably in the winter and summer seasons. The AWC and the length of growing period of crop have also contributed to the NIR values. Soils with higher AWC had lower NIR while crops with longer growing season showed higher NIR. The AWC of soils has been found to be mainly governed by the soil texture more so by the clay + silt or clay contents. In general, medium textured soils had higher AWC than either coarse or fine textured soils. The 60 per cent level of depletion of AWC has been used to initiate irrigation. The number of irrigations required and the quantity of water applied depends on the overall evaporative demand of climate, the length of growing season of the crop and the AWC of soils. Seasonal evaluation of the scheme water supply efficiency revealed that in general the values were below 1.0 and tended to be around 0.5. The values were around 0.5 during the months of high evaporative demand and considerably less during the monsoon and cooler months when the evaporative demand is lower. However, these values are expected to be higher once all the crops grown will be considered. Scheme efficiency (relation between supply required and actual supply) can be improved by growing perennial crops like sugarcane and banana and such other crops having a high requirement for water. Such crops are recommended to be grown on as soils with no root zone limitations or other limitations imposed by the physical and chemical properties of soils. During months of low water requirement use of exploitable ground water is also recommended. Such conjunctive use will help in saving water which otherwise will go as wasteful flow and also help to keep the ground water level well below problematic levels. Use of data on soil-crop-climate to achedule irrigations for the various crops revealed it to have substantially leas NIR values as compared to the IW/CPE ratio for monsoon season crops and compared well for the winter crops. In the summer, it predicted a less NIR than IW/CPE for groundnut but gave higher values than IW/CPE for pearl millet. The redeeming feature of the model is that it takes into consideration the effective rainfall (Total rainfall less that lost through run-off or deep percolation). The soil-crop-climate model compared well with the other methods of irrigation tried, for the yield of grain in all the crops studied. It gave less WUE than the critical stages approach for all the crops except wheat, where Ife gave higher WUE values. In case of pearl millet and mustard it gave less WUE than the IW/CPE ratio. This may be attributed to the fact that these crops have basically less requirement for water and hence, gave no significant response to any increase in water supplies beyond a certain level. Studies on the behaviour of the model as compared to the other schedules for the nutrient depletion pattern Indicate that no definite pattern with respect to nutrient uptake has emerged and the results had a fair measure of inconsistency. The inherent variability of the crops studied for their capacity of derive nutrition, the natural relationships among the nutrients and the inherent difference in the soil's capacity to supply nutrients can be attributed to the observed inconsistency. Since the model gives moderate dry matter production, it causes moderate depletion of nutrient and hence with proper management and monitoring of the soil fertility, it is expected to give sustained agricultural production. Study on evolving alternative irrigation management practices in areas suffering from problems of rising water table were carried out. Results revealed that for groundnut use of sprinkler system of irrigation with an application depth corresponding to 2.5 cm per irrigation at two stages of crop growth viz. pegging (55 DAS) and pod development (85 DAS) with two irrigation of 5 cm each as pre-sowing and pre-harvest proved to the most beneficial (5.7 t/ha kernel yield). Growing groundnuts without Irrigation (4.6 t/ha) except a pre-sowing irrigation was the next best alternative. Irrigating groundnut at pre-sowing, 55 DAS, 85 DAS and pre-harvest stages with 5 cm depth of application each time had serious negative effects on yield (2.6 t/ha). Under such situations use of sprinklers appears to be a promising alternative as besides giving higher yield it may also help in keeping the ground water level within manageable limits. Growing groundnut without irrigation appear to be the next best alternative. From the study conducted It can be concluded that the soil-crop-climate model, can be used as an effective tool for predicting regional estimates of irrigation requirement inspite of the wide diversity of climate, soil and crops grown In any region, because it takes into consideration these very variables. It is also easy to compute the requirement and has the added advantage of using minimum data sets. The data collected once can be applied without the need for recurrent data collection for a reasonably long time. However, before final conclusions can be drawn, the model needs to be validated for larger number of crops, wider variety of soils and different climatic situations. Because of its requirement of minimum data sets, however it appears to be an attractive alternative tool for making regional estimates of water requirement and merits scientific attention.en_US
dc.identifier.urihttp://krishikosh.egranth.ac.in/handle/1/5810049057
dc.keywordsASSESSMENT OF IRRIGATION REQUIREMENT, NARMADA COMMAND, SOIL-CROP-CLIMATE DATAen_US
dc.language.isoenen_US
dc.publisherAAU, Ananden_US
dc.research.problemASSESSMENT OF IRRIGATION REQUIREMENT OF NARMADA COMMAND USING SOIL-CROP-CLIMATE DATAen_US
dc.subSoil Science and Agriculture Chemistryen_US
dc.subjectAgricultural Chemistry and Soil Scienceen_US
dc.subjectASSESSMENTen_US
dc.themeASSESSMENT OF IRRIGATION REQUIREMENT OF NARMADA COMMAND USING SOIL-CROP-CLIMATE DATAen_US
dc.these.typePh.Den_US
dc.titleASSESSMENT OF IRRIGATION REQUIREMENT OF NARMADA COMMAND USING SOIL-CROP-CLIMATE DATAen_US
dc.typeThesisen_US
Files
Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
JAYANT DATTATRAYA GIRI.pdf
Size:
12.58 MB
Format:
Adobe Portable Document Format
Description:
Ph.D (Agricultural Chemistry and Soil Science) Dissertation
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Theses