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21.
Irrigation distribution equity and crop growth were studied in Delhi Sub-branch of Western Yamuna Canal Command. Total irrigation
was estimated from the canal and tube well discharge data and irrigation distribution equity was expressed in terms of Theil’s
and Christiansen’s Coefficients for nearly 140 wheat fields randomly chosen over the command. Crop growth performance for
these plots was assessed from the Normalized Difference Vegetation Index (NDVI) obtained from the IRS, LISS II data. Four
soil associations viz., Nabha-Ghoga, Daryapur-Hissar, Holambi-Nabha and Khampur-Hissar mainly represented the study area.
In general, increase in amount of irrigation enhanced the growth performance of the wheat crop. Increase in distribution equity
within soil associations slightly improved the growth performance of the crop. Over and above, the irrigation equity, quality
and quantity constraints to irrigation, the other soil parameters like CEC, applied P also contributed to differences in wheat
growth as observed from the stepwise multiple regression analysis. Irrigation performance indices were estimated from water
distribution between soil associations and from water requirement of crop, indicated performance slightly below the critical
level. 相似文献
22.
S. Raut K. S. S. Sarma D. K. Das 《Journal of the Indian Society of Remote Sensing》2010,38(2):321-331
Irrigation water requirements of wheat and mustard crops grown in Western Yamuna Canal Command area were estimated using FAO
model CROPWAT with the help of agrometeorological and remote sensing data (1986–1998 and 2008). The variations in irrigation
water requirements of these two crops were judged by calculating coefficient of Variations (CVs) of yearly data. Crop coefficient
values were obtained through FAO (1993) method. Supervised Maximum Likelihood Classification (MXL) of IRS 1B image was done
to estimate area under wheat and mustard in the canal command. Water need was calculated from amount of supply and water requirement
for the whole area. Results showed that ETcrop values of both wheat and mustard varied very little over different years (CVs 4.7% and 5.6% respectively). Irrigation water
requirements of both these crops were having relatively large variations (CVs 14.1% and 22.6% respectively) which were mainly
because of high variations of their effective rainfall (CVs 61.1% and 69.2% respectively). In general, increase in amount
of irrigation enhanced the growth performance of the wheat crop. Increase in distribution equity within soil associations
slightly improved the growth performance of the wheat crop. Agro-climatic data merged with satellite image approximated the
deficiency of applied irrigation amount (549.5 ha-m for wheat and 692.7 ha-m for mustard) as compared to requirement. 相似文献
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