الفهرس 
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Abstract
The objective of this investigation to monitor and evaluate the land use classification, water consumption, water productivity, biomass production and soil salinity by using remote sensing data, GIS techniques, and field data. El-Moheet branch canal command area was selected for mapping cropping pattern, crop evapotranspiration and biomass yield as well as soil salinity for winter and summer seasons before and after irrigation improvement. The selected canal is located in Kafr El Sheikh District, Kafr El Sheikh Governorate, in North Nile-Delta, Egypt. El-Moheet canal (about 3.5 km in length) is an earthen branch canal located at the 35 km on the right side of Meet Yazied main canal and it feeds an area of about 640 hectares. This canal was subject to irrigation improvement practices (Mesqas and Marwas). This study was carried out during four seasons started in November 2010 and ended by the end of the summer season in 2013. This period covered two growing seasons before irrigation improvement (2010/2011 and 2011) and two growing seasons after irrigation improvement (2012/2013 and 2013). The obtained results can be summarized as follows: Land use classification: Summer crop classification: The landsat images were classified into seven field crops. Based on the acreage of each crop, cotton was the dominant crop before irrigation improvement (42.7%) followed by rice (33.3%), seed melon (14.5%) and maize (9.5%). However, an opposite trend was recorded after the improvement, where rice was the dominant summer crop (74.1%) followed by seed melon (10.7%), cotton (9.2%), and maize (6.0%). The percentage of rice was increased after irrigation improvement. In the contrary of rice, cotton, maize and seed melon were clearly decreased after improvement. The significant increase in rice area after the improvement could be attributed to the improvement in the availability of irrigation water and the equal distribution of irrigation water, especially at the tail-end area. The obtained images also showed that the cultivated area was decreased from 2011 to 2013 by about 4% due to urban encroachment. On the contrary, the non-cultivated area was increased by about 25% after irrigation improvement. Winter crop classification: Three types of winter crops were indentified in the studied area, which are wheat, sugar beet, and clover. This is in addition to urban, open water and roads. Data indicated that the cultivated area was decreased from 2010/2011 to 2012/2013 by about 5%, whereas the non-cultivated area was increased by about 26%. This could be due to changes in land uses from agricultural to non-agricultural activities. Data also, revealed that sugarbeet was the dominant winter crop in the studied area before irrigation improvement (66.7 %), followed by clover (20.7%) and wheat (12.6%). After irrigation improvement the cultivated area was almost equally divided among the three winter crops. The wheat area was increased after irrigation improvement and represent about 35.5 % of the cultivated area, followed by sugarbeet (32.6 %) and clover (31.9 %). So, it could be concluded that irrigation improvement had a positive effect on wheat and clover areas, and a negative effect on the sugar beet area. This could be attributed not only to the irrigation improvement, but also to the economic and marketing conditions. Crop Evapotranspiration (ETc): Summer Crops: The values of the actual evapotranspiration (ETc in mm/day) were derived from Landsat images for the different crops along El-Moheet canal. The obtained data showed that the average daily ETc in summer 2011 for rice, cotton, seed melon and maize were 6.1, 5.2, 4.8 and 4.4 mm/day, respectively during the period from August first to the end of September. The total ETc for rice, cotton, seed melon and maize in the three months were 549, 468, 432 and 396 mm, respectively. The ETc in m3/ha for this period were 5490, 4650, 4290 and 3990 m3/ha, for the previous crops, respectively. Irrigation requirements were calculated by dividing ETc values by the irrigation efficiency at mesqa level. Irrigation efficiency at mesqa level before improvement was supposed to be 60% with rice and about 70% with the other crops. However, after the improvement the efficiency was raised to about 70% with rice and about 80 % with the other crops due to raise in water efficiency by about 15%. Therefore, water requirement was 9150, 6643, 6129 and 5700 m3/ha with rice, cotton, seed melon and maize, respectively. After irrigation improvement in 2013 the average daily ETc for rice, cotton, seed melon and maize were 6.13, 5.07, 4.37 and 4.03 mm/day, respectively from August first to the end of September. The actual water consumption was higher with rice when compared with the other crops during the considered months. The total ETc for rice, cotton, seed melon and maize in that period, was 552, 456, 393 and 363 mm, respectively. The ETc in m3/ha for that period was 5517, 4563, 3933 and 3627 m3/ha, for these crops, respectively. Therefore, water requirements for different crops were 7881, 5704, 4916 and 4534 m3/ha with rice, cotton, seed melon and maize, respectively. So, rice area requires more water in 2013 followed by cotton due to rice crop dominates in this season (after improvement) followed by cotton. While before irrigation improvement, more water was required for cotton area because it dominated in this season, followed by rice. It could be concluded from the Landsat data that the overall water consumption (ETc//ha) and water requirements were decreased between 2011 and 2013. Winter Crops: The average daily actual (ETc) for sugarbeet, wheat and clover before the improvement (2010/2011), was 3.5, 3.0 and 1.7 mm/day, respectively. The total ETc for these crops in three month (December, February and March) were 315, 270 and 153 mm, respectively. The total ETc for the three studied crops before irrigation improvement were 3150, 2700 and 1530 m3/ha, respectively. The irrigation requirement was calculated by dividing ETc values by the irrigation efficiency at mesqa level. Therefore, water requirements or irrigation water to be applied to sugar beet, wheat and clover were 4500, 3857 and 2186 m3/ha, respectively. The average daily ETc after irrigation improvement was lower than that before irrigation improvement by about 22%, although it had 0.42% higher sunshine hours and 11.3 % higher total temperature. The average of ETc values in the three studied months for sugar beet, wheat and clover were 2.70, 2.43 and 1.30 mm/day, respectively. The total ETc for these crops in these 90 days was 243, 219 and 117 mm, respectively (2430, 2190 and 1170 m3/ha, respectively). Water requirements for sugarbeet, wheat and clover were 3038, 2738 and 1463 m3/ha, respectively. It can be concluded that the ETc values (mm or m3/ha) for the studied winter crops along the branch canal weren’t significantly affected by irrigation improvement, but was mainly affected by the meteorological conditions and the crop pattern in the area that is affected by the situation of the irrigation system. Crop biomass yield: Biomass yield of summer crops: The biomass yield was calculated from the NDVI values derived from the landsat images. The average biomass yield for rice before the improvement was 23.9 tons/ha and it was decreased to 20.3 tons/ha (about 15% reduction) after the improvement. The highest biomass yield for rice was recorded in the middle-reach (21.4 ton/ha), whereas the lowest yield was found in the head-reach area (17.8 ton /ha). The biomass yield for seed melon was 9.9 ton/ha (less than 2011 by about 7 %). The biomass distribution of seed melon along the branch canal was similar to that of rice. The average biomass yield for cotton was 19.5 tons/ha in 2011, and it was 19.1 tons/ ha in 2013 (about 2.1 % yield reduction). Along the branch canal, the cotton biomass yield was gradually decreased from 19.0 tons/ha on the head-reach to 18.3 on the middle-reach and to 14.5 tons/ha on the tail-reach area. On the contrary, the biomass yield of maize was higher after irrigation improvement (44.9 tons /ha) than that before the improvement (45.2 tons/ha). The head-reach of the branch canal recorded the highest biomass yield of maize, whereas the middle-reach had the lowest yield (40.8 tons /ha). Biomass yield of winter crops: The obtained results indicated that sugarbeet and clover had an increase in biomass yield after irrigation improvement than that before the improvement. Sugarbeet biomass was increased from 69.8 to 78.6 tons/ha (about 12.6% increase), whereas clover increased from 17 to 18.4 tons/ha (about 8.4% increase). Wheat biomass yield didn’t change much before and after irrigation improvement, it was about 17 tons/ha. These results revealed that IIIMP has significant impact on biomass yield of sugarbeet and clover, which relatively need high water requirements, although wheat wasn’t affected by the improvement. These results may be attributed to the improvement in both irrigation efficiency and equity in water distribution along the studied canal. Crop water productivity: Water productivity (WP) for the summer crops: The WP values for both rice and seed melon were decreased after irrigation improvement than that before the improvement. The average WP value for rice was decreased from 4.4 to 3.7 kg/m3 in 2011 to 2013, respectively. However the average WP value for seed melon was decreased from 2.7 to 2.6 kg/m3 in 2011 to 2013, respectively. On the contrary, the WP value for maize was increased after irrigation improvement than that before the improvement. The average PW value was 10.5 kg/m3 in 2011and 11.4 kg/m3 in 2013, after improvement (about 8.6% increase). The WP for cotton wasn’t affected much by irrigation improvement (4.2 kg/m3). Irrigation Water Productivity (IWP) is the result of dividing the crop biomass yield for each crop by its water requirements. The average of IWP was lower than that of WP (about 5.4 and 3.7 kg/m3, respectively) and it was increased after improvement (2013) for all of the studied summer crops except for rice. The values of IWP for cotton maize and seed melon were increase after irrigation improvement in 2013 by about 17.2, 23 and 10.50 %, respectively. Water productivity (WP) for the winter crops: The obtained data reveal that the overall average values of WP and IWP after improvement were raised from 13.3 and 9.3 kg/m3, respectively to 18.7 and 13.6 kg /m3, respectively, which represent a positive change of about 41 and 46 %, respectively). Also, the WP and IWP values for all winter crops were obviously increased after irrigation improvement (season 2012/2013). This could be attributed not only to IIIMP but also to the longer sunshine hours and the higher temperature degrees in 2012/2013. The ratio of WP and IWP after improvement in 2012/2013 exhibited a larger increase in their values for sugarbeet when compared with their values before the improvement in 2010/2011 (+ 46 and 67 %, respectively). However, for wheat and clover there were a reasonable increase in the WP (23 and 39.8, respectively) and the IWP (39.5 and 8.9 %, respectively) within the improved area. The head/tail ratios of both WP and IWP for all crops along El-Moheet canal within the two winter seasons were varied between 0.98 and 1.0, which indicate no head/tail trend. This can be explained by the high uniformity observed in the biomass yield and water consumption for winter crops. Soil Salinity: Soil salinity within the studied area was acceptable for agricultural activities. However it was slightly decreased by about 8% after irrigation improvement. The head/tail analysis revealed that soil salinity was homogeneously distributed along the branch canal, especially after irrigation improvement. This also implies that the salinity status in the investigated area is approximately stable. This situation could be due to the constant cultivation of rice, which needs an excessive application of irrigation water. Final Conclusion:* Remote sensing and GIS techniques could be very valuable tools in monitoring and evaluating the changes in land use, crop pattern classification, water consumption, water productivity, biomass production and soil salinity mapping, when compared with the conventional methods which need more time, effort and labor. * With the completion of irrigation improvement of El-Moheet branch canal, considerable changes were happened with regard to cropping systems.* Irrigation improvement increased the areas of wheat, clover and rice with simultaneous decrease in the areas of sugarbeet, cotton, maize and seed melon.* The major conclusion that the irrigation improvement had significant impact on head/tail differences, due to irrigation improvement processes. Rice and sugarbeet were shifted toward the tail-end areas, whereas wheat was concentrated in the head-reach area.* The changes in crop consumptive use were governed by meteorological conditions rather than by irrigation improvement processes.* Water consumption was very uniform along the branch canal, therefore, after irrigation improvement, less head/tail differences were observed.* The improved area required less water than the unimproved area and irrigation improvement can improve the uniformity to water resources.* The overall uniformity in biomass yields for all summer crops between head and tail-end of the branch canal were decreased after improvement, whereas winter crops were not significantly affected.* The satellite images before the improvement showed low contrast in biomass yield between the head and the tail, while after the improvement they showed large differences.* Regarding water productivity for all winter crops, no significant head/tail trends were found before or after irrigation improvement.* Already improved branch canal showed a larger increase in crop or irrigation water productivity. * Irrigation improvement slightly decreased soil salinity and had an effect on its distribution along the investigated branch canal.Final recommendation: The improvement of on-farm irrigation system (meskas and marwas) and applying proper crop pattern (the rice should not be the dominant crop) are very important for water saving.