UTILIZING REMOTE SENSING TO MANAGE IRRIGATION WATER FOR DIFFERENT CROPS

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1 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt 759 UTILIZING REMOTE SENSING TO MANAGE IRRIGATION WATER FOR DIFFERENT CROPS Nagy Yakoub Associate Professor, National Water Research Center, Ministry of Water Resources and Irrigation, Cairo, Egypt ABSTRACT Several organizations are using satellite images in the field of water resources and agriculture including the National Water Research Center (NWRC). Satellite images such as Landsat are used in land cover classification, water resources management, water quality evaluation, and crop area estimation. The main crops in Egypt are Cotton, wheat, and Rice and because of the large fluctuation in the areas and locations of these crops over the years, a great deal of effort is put in place to supply the proper amount of water to the various crops on time. Management of water resources in Egypt became extremely important especially after the free crop pattern strategy is applied. To efficiently manage the water resources in Egypt for irrigation, it is important to understand the crop pattern distribution, particularly in the summer, where demand for water increase tremendously. To effectively manage the water resources in Egypt for irrigation purposes, it is extremely important to determine the water demand for different crops on time. The free crop pattern distribution policy requires more information about the crop area estimation and its location to manage water demand for irrigation. The purpose of this paper is to utilize remote sensing technique for irrigation water management on the directorate level. The paper would assess the relationship between the available water resources and crop pattern distribution in the Qalubiya directorate. The Qalubiya directorate is chosen for this study to estimate the main crops area during the summer because it represents the old land in the Delta area and the study is during the summer because of the increased water demand for irrigation in the summer. The Landsat image would be analyzed using remote sensing technique to classify the major crops in the directorate during the summer. To assess and discuss the shortage of irrigation water in the directorate during the summer, classification of crops would be coupled with the monthly distribution of irrigation water in different canals of Qalubiya directorate. The estimated crop areas could help in managing the water resources to the area for optimizing the irrigation schedule in both irrigation water discharge quantity and timing, in addition to, reducing the spilled water to the drains. Keywords: Water Resources, Remote Sensing, Crops, Irrigation Water

2 760 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt INTRODUCTION Several organizations are using satellite images in the field of water resources and agriculture including the National Water Research Center (NWRC) and Agriculture Research Center (ARC). Satellite images such as Landsat TM are used in Egypt in several fields including land cover classification, water quality evaluation, and crop area estimation which would be used in this paper. The main crops in Egypt are Cotton, wheat, and Rice and because of the large fluctuation in the areas and locations of these crops over the years, a great deal of effort is put in place to supply the proper amount of water to the various crops on time. Management of water resources in Egypt became extremely important specially after applying the free crop pattern strategy by ministry of Agriculture in the 90's of last century. To efficiently manage the water resources in Egypt for irrigation, it is important to estimate the crop area particularly in the summer where demand for water increase tremendously. OBJECTIVE The fresh water resources in Egypt are limited and to effectively manage the water resources in Egypt for irrigation purposes, it is extremely important to determine the water demand for different crops on time. In the past, fixed crop pattern distribution made it more manageable to supply the required irrigation water into the proper location on time for different crops. Nowadays, because of the free crop pattern distribution policy, it requires more information about crop area estimation and location to manage water demand for irrigation. The purpose of this paper is to optimize the irrigation water schedule by utilizing remote sensing technique to analyze Landsat images for crop area estimate and location. By defining the location and area of each crop, the Irrigation sector would discharge the proper amount of irrigation water in each canal to match each crop needs on time. The Qalubiya directorate is chosen for this study to estimate the main crops area during the summer and its location. This directorate was selected because it represents the old land in the Delta area which uses traditional irrigation methods, and the study is carried out during the summer because of the increased water demand for irrigation in the summer. IRRIGATION WATER MANAGEMENT IN EGYPT Irrigation water management starts with demand forecasting, followed by allocation of water among the different demands and then, distribution of those allocations with the proper quantity on time. These steps would require spatial and temporal discharge of water through a good operation of the system infrastructures.

3 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt 761 At the beginning of each water year in Egypt, the ministry of water resources and irrigation calculate the water budget for the following year. The irrigation water demand is based on the estimated cropping pattern provided by the Ministry of Agriculture and Land Reclamation. All water demand for irrigation, municipal, industrial, hydro-power, and navigation are aggregated to forcast the total water demand (SRP [10]). The total demand is matched against the total supply to adjust any differences. The important step is to determine the temporal distribution of irrigation demand which would guarantee the delivery of irrigation water to the right location in the proper time (Attia, B., [8]). Due to the errors in estimating the cropping pattern, in both areas and locations, there is always mismatch between the supplied irrigation water and the demand either in the supplied quantity of water or the timing of irrigation. It is clear from this mismatch that the precise estimate of cropping pattern distribution in both areas and locations is extremely important. The satellite images are one of the available tools to determine preciously the areas of the main crops and its exact locations. If this technique could be applied periodically and comprehensively, it could help in determining more accurately the irrigation water requirements for the remaining of the season, and help in planning future irrigation requirements. WATER RESOURCES EVALUATION IN QALUBIYA The water resources evaluation in Qalubiya directorate include the actual directorate's share of irrigation water to the main canals and distributed on monthly bases, planned water requirements, drainage water, and Municipal and Industrial water requirements. The Qalubiya directorate is located to the east of the Rosseta Branch of the Nile and north of Cairo city as shown in Figure (1). The Ministry of Water Resources and Irrigation plan for the water requirements for each directorate and for each crop in that directorate. The Qalubiya irrigation directorate consists of 8 districts with a total area of 327,235 feddan which is Shoubra, Qalub, Tokh, Banha, Kafr Shoukr, Shebeen El Khanater, Bilbes, and Mashtoul El Souk (Irrigation Sector [11]). The main five canals supply water to Qalubiya directorate are El Sharkawiya, El Basusiya, Abou El Menaja, Al Ismailiyyah, and Rayah El Tawfiqi as shown in Figure (2). The command areas served by each canal in Qalubiya directorate are given in Table (1).

4 762 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt Table 1. Canal Command Area served for the main canals in Qalubiya Directorate Canal Area served El Sharkawiya El Basusiya Abou El Menaja Al Ismailiyyah Rayah El Tawfiqi Total The Ministry plans for water requirements to satisfy the demands for irrigation, Municipal, Industrial, and Navigation. Due to the actual crop pattern distribution and the irrigation system condition, the ministry supply extra discharge upon request and the total supply gives the actual water discharged to the system. The planned and actual water discharge to different canals and distributed on monthly bases to Qalubiya directorate are given in Tables (2), and (3) which totals about 2.2 BCM/year (Irrigation Sector [11]). The Qalubiya directorate has a considerable number of wells, but mainly for drinking purposes and the amount of Groundwater used for irrigation purposes is limited, and not deducted from the directorate share of the Nile water. Table 2. Actual Water Supply to Qalubiya for the main canals in 2001 (MCM/month) Canal Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Total El Sharkawiya El Basusiya Abou El Menaja Al Ismailiyyah Rayah El Tawfiqi Total

5 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt 763 Table 3. Planning Water Demand to Qalubiya for the main canals in 2001 (MCM/month) Canal Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Total El Sharkawiya El Basusiya Abou El Menaja Al Ismailiyyah Rayah El Tawfiqi Total Municipal and Industrial Water The Municipal and Industrial water requirements is about 1.7 MCM/day distributed on three of the five main canals as follows: El Sharkawiya Canal = 0.5 MCM/day = 15 MCM/month Al Ismailiyyah Canal = 1.0 MCM/day = 30 MCM/month Ryah El Tawfiqi = 0.2 MCM/day = 6 MCM/month Where the total Municipal and Industrial water requirements for Qalubiya directorate is 643 MCM/year (Irrigation Sector [11]). 2. Irrigation System The Qalubiya irrigation directorate boundary exceeds the Qalubiya agriculture department boundary by two of the eight districts forming the irrigation directorate (Bilbes, and Mashtoul El Souk) with an area of 106,000 feddans. The planned and actual water requirements are given for the total area of the irrigation directorate and it would be modified to reflect the requirements for Qalubiya agriculture department. The Qalubiya agriculture department boundary has a total area of 221,235 feddans and, the actual and planned water requirements, after deducting the requirements for the two districts, municipal, and industrial water requirements, are given in Tables (4), and (5).

6 764 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt Table 4. Actual Irrigation Water Supply to Qalubiya for different Crops in 2001 (MCM/month) Canal Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Total El Sharkawiya El Basusiya Abou El Menaja Al Ismailiyyah Rayah El Tawfiqi Total Table 5. Planned Irrigation Water Demand to Qalubiya for different Crops in 2001 (MCM/month) Canal Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Total El Sharkawiya El Basusiya Abou El Menaja Al Ismailiyyah Rayah El Tawfiqi Total Drainage System The drainage system in the East Delta mainly drains into Lake Manzala. The main drainage systems in the area include Bahr El Baqar and Bahr Hadus drainage systems. Qalubiya drains are part of Bahr El Baqar drainage system. The drainage water flows by gravity from Qalubiya and Bilbis drains into Bahr El Baqar drain. The directorate does not have an official drainage reuse where the drainage system in Qalubiya directorate is presented in Figure (3). Bilbis drain carries the sewage effluence of Cairo into Bahr El

7 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt 765 Baqar drain and Qalubiya drain caries both drainage water and Shobra El Kheima sewage effluence, also, into Bahr El Baqar drain. The agriculture land in Qalubiya directorate is covered with tile drainage system. CROP PATTERN DISTRIBUTION AND WATER DUTIES The crop pattern distribution for the Qalubiya department is calculated by The Ministry of Agriculture and Land Reclamation, in The Economic Affairs Sector (EAS), which is in charge of producing the agricultural production statistics in Egypt. Table (6) presents the summer crop areas in Qalubiya department for the year The total area of the department is 270,364 feddan and the total cultivated area in the Summer of 2001 is 198,721 feddans (EAS [6]). Table 6. Crop Pattern Distribution in Qalubiya department for the Summer of 2001 (feddan) Crop Rice Corn Soybean Peanut Sugarcane Forage crops Area 14,577 87, ,288 Crop Cotton Onion Vegetables Potatoes Orchards Palm Total Area 12,678 1,948 13,110 2,860 48, ,721 The irrigation sector (MWRI) regulates the releases of irrigation water on spatially and temporally basses depending on the area of each crop (collected by MALR). The monthly water duties are estimated for each crop, where the monthly water duties for the two major crops in Qalubiya department (Cotton, and Rice) are calculated by the irrigation sector and presented in Table (7). Table 7. The monthly water duties for Cotton and Rice (CM/F) Crop Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Total Cotton Rice

8 766 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt RICE CROP CULTIVATION The Rice is cultivated in Egypt for local use and part of it as an export crop. In addition to that, the Rice is cultivated north of the Delta area to reduce the sea water intrusion near the north coast and its effect on the groundwater. Also, because the Rice crop consumes a large amount of fresh water, the irrigation sector (MWRI) regulates the area and location of Rice cultivation. The irrigation sector regulates every year the area that would be cultivated with Rice and Figure (4) presents the permitted Rice cultivation areas and its locations for the summer of 2001 with a total of 1.07 million feddans. As shown in the figure, it is not permitted to cultivate Rice in Qalubiya Agriculture department. The Economic Affairs Sector report for the summer of 2001 reported that the area cultivated with Rice in Qalubiya agriculture department is 14,577 feddans and the total area cultivated with Rice in Egypt is 1.5 million feddans (EAS [6]). CROP CLASSIFICATION USING SATELLITE IMAGES Several organizations are using satellite images in the field of water resources and agriculture including the National Water Research Center (NWRC) and the Agriculture Research Center (ARC). Satellite images such as Landsat are used in Egypt in several fields including land cover classification (Townshend, J.R., [4]), water quality evaluation, and crop area estimate which would be used in this paper. The main crops in Egypt are Rice, Cotton, and Wheat, and because of the large fluctuation in the areas and its locations for those crops over the years, a great deal of effort is put in place to supply the proper amount of irrigation water in different canals to the various crops on time. Management of water resources in Egypt became more difficult particularly after applying the free crop pattern strategy by the Ministry of Agriculture and Land Reclamation in the 90's of last century. In this study, Landsat images would be used for the Qalubiya agriculture department in the Summer of 2001.

9 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt 767 METHODOLOGY To efficiently manage the water resources in Egypt for irrigation purposes, it is important to estimate the crop areas and its locations particularly in the summer where demand for water increases tremendously and puts more pressure on the irrigation system. By defining the location and area of each crop using satellite images, the Irrigation Sector would direct the proper amount of irrigation water to each canal in the proper time. The Rice crop area and location in Qalubiya agriculture department for the summer of 2001 would be used to demonstrate this technique. IMAGE CLASSIFICATION TECHNIQUE Image classification techniques are aiming at categorizing image pixels into land cover classes. The multi-spectral data are used to perform the classification where the spectral pattern presented within the data for each pixel is used as the numerical basis for categorization. The technique used in this paper is the supervised classification method which is the backbone of most classifications. The method is used when it is easy to identify distinct and homogeneous regions that represent each class (Ismail M. [7]). Ground truth is used to support the classification, where it is important to collect some information from the field such as the location of land cover type to perform the actual classification of multi-spectral image data. The resulted classified image would include five classes of Cotton, Rice, Other crops, Urban areas, and Desert. Image Classification of the Study Area The study area selected for crop area estimate is the Qalubiya agriculture department. The satellite image used for this study is the Landsat ETM images for the summer of 2001 with seven bands and a resolution of 30 meters. Figure (1) shows the Landsat image for the area with the main Canals, Nile, and the boundary delineating the Qalubiya agriculture department. The Remote Sensing and Geographic Information System Unit of the Agriculture Research Center produces the land cover classification which includes the areas and locations of the two main summer crops (Cotton, and Rice), the area of other crops, the urban area, and the desert. The produced land cover classification for Qalubiya agriculture department is presented in Figure (5). Different areas would be calculated from the classification including the total area of the Qalubiya agriculture department, the area of each of the two main crops (Cotton, and Rice), the area of other crops, the urban area, and the desert area. The five different classes and the area of each class are presented in Table (8).

10 768 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt Table 8. Image Classification Areas for Qalubiya agriculture department (feddan) Class Cotton Rice Other Crops Urban Area Desert Total Area 12,678 14, ,466 23,425 48, ,360 RESULTS AND DISCUSSIONS Each Directorate get its share of irrigation water from the irrigation sector based on the directorate request for daily discharge for each canal based on there actual needs. Based on the actual needs of each canal, the sector could add extra water to some canals or subtract water from other canals without exceeding the annual discharge to the directorate. Tables (4) and (5) present the actual and the planed discharge to the

11 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt 769 main canals in Qalubiya agriculture department and the difference between the actual and the planned irrigation water in 2001 (MCM/month) is shown in Table (9). In Table (9), it is clear that some canals receive more than planed share of irrigation water, and others receive less than there share. Also, this mismatch varies from one month to another, especially in the summer months. In addition, extra discharge of 55 MCM/year is added to the department share of irrigation water. The Qalubiya agriculture department is cultivated with illegal area of Rice crop equal to 14,577 feddans, which is not counted for in the planned irrigation discharge to the department. The annual water duty for Rice crop as shown in Table (7) is CM/feddan/year and the average annual water duty for many of the other crops is about 4000 CM/feddan/year. This creates an extra water duty for the illegal Rice irrigation of about 3000 CM/feddan/year. Calculating the extra water duty for Qalubiya agriculture department to substitute for the illegal area of Rice cultivation would yield 43.7 MCM/year which is not far from the extra irrigation water discharged to the department with a total of 55 MCM/year as shown in Table (9). Other reasons for the extra difference between the two numbers would be the substitution for weeds in the canals that requires the increase of discharge to raise the water elevation in the canals, so it can reach the tail end of the canals, and also, lack of farm irrigation at night which may waste irrigation water to the drains. Another important remark is the spatial distribution of Rice areas in the directorate as shown in Figure (6) and comparing its location with positive and negative substitution of irrigation water in Table (9). So, the results of applying this technique on the Qalubiya agriculture department could be summarized as follows:

12 770 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt Table 9. Difference between Actual and Planned Irrigation Water to Qalubiya in 2001 (MCM/month) Canal Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Total El Sharkawiya (1) 4 1 (4) 0 (1) 24 El Basusiya 5 7 (3) 0 (8) (10) (5) 6 (7) (1) (2) 6 (11) Abou El Menaja Al Ismailiyyah (13) (34) (1) (2) (8) (20) (12) (9) (6) (84) Rayah El Tawfiqi 1 13 (10) (10) (12) (15) (13) (9) (3) (1) (24) Total 3 10 (5) 4 (10) (4) (1) The locations of Rice cultivation are heavily concentrated in the southern part of the Qalubiya agriculture department more than its northern part because of the availability of enough irrigation water for Rice cultivation near the head of the canals. 2. The area of Rice cultivated along Ismailiyyah canal is very small which explains the deduction of Ismailiyyah canal's share of irrigation water as shown in Table (9) to substitute for other needed areas. 3. The heavy areas of Rice cultivation are concentrated along Abou El Menaja and El Sharkawiya canals which explain the substitution of extra irrigation water into those two canals especially during the Summer season. 4. The irrigation water discharged to Qalubiya agriculture department increased by 55 MCM/year which is a little over the 43.7 MCM/year needed to substitute for the illegally cultivated Rice area. But, there was a reallocation of irrigation water among the canals inside Qalubiya agriculture department to satisfy the actual requirements based on the actual crop pattern distribution. 5. Concentration of Rice cultivation in some Qalubiya areas causes the increase of irrigation water withdrawn from these areas. Consequently, the water level and the amount of irrigation water at the tail end of the canals at those areas are decreased. This raise the farmers complains of water shortage at the tail end of the canal and drive the irrigation sector to compensate the shortage of water with an amount matches the illegally cultivated Rice area. CONCLUSIONS AND RECOMMENDATIONS In this research, the irrigation water schedule would be optimized by utilizing remote sensing technique to analyze Landsat images for crop area estimate and location. By defining the location and area of each crop, the Irrigation sector would discharge the proper amount of irrigation water in each canal to match each crop requirements on

13 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt 771 time. This would save fresh water, reduce drainage water, and increase crop productivity. The Qalubiya agriculture department is chosen for this study to estimate the main crops areas and locations during the summer of This department was selected because it represents the old land in the Delta area which uses traditional irrigation methods, and the study is carried out during the summer because of the increased water demand for irrigation in the summer and the illegal cultivation of Rice crop. The study analyzed the effect of illegal Rice crop cultivation on the irrigation water discharge quantity and its reallocation to fulfill different crops requirements using satellite image classification of the major crops in Qalubiya agriculture department. The study showed that the areas of Rice cultivation are heavily concentrated in the southern part of the Qalubiya agriculture department more than its northern part because of the availability of enough irrigation water for Rice cultivation near the head of the canals. The area of Rice cultivated along Ismailiyyah canal is very small which explains the deduction of Ismailiyyah canal's share of irrigation water to substitute for other needed areas. The heavy areas of Rice cultivation are concentrated along Abou El Menaja and El Sharkawiya canals which explain the substitution of extra irrigation water into those two canals especially during the summer season. The irrigation water discharged to Qalubiya agriculture department increased a little over the amount needed to substitute for the illegally cultivated Rice area. In addition, there was a reallocation of irrigation water among the canals inside Qalubiya to satisfy the actual requirements based on the actual crop pattern distribution. Concentration of Rice cultivation in some Qalubiya agriculture department areas increased the irrigation water withdrawn from these areas. Consequently, the water level and the amount of irrigation water at the tail end of the canals at those areas are reduced. This raises the farmers complaints of water shortage at the tail end of the canals and drive the irrigation sector to compensate for the shortage of water with an amount matches almost the illegally cultivated Rice area. As presented, this technique of utilizing remote sensing could be used to estimate the areas and locations of major crops in Egypt during the summer and the winter. This method would cover large areas, produce fast, reasonable, and accurate results instead of the manual survey method that would take time, cost, effort, and could be subject to error. The irrigation sector would quickly use the resulted spatial crop areas estimate in regulating the irrigation water distribution in the canals and targeting the needed areas with irrigation water on time. Also, this technique could help in a better forecast of the irrigation water demand for preparing the water budget in the following year. It is recommended to use this technique for the Delta area by deploying affordable satellite images such as Landsat images to manage the irrigation water more efficiently, reduce drainage water, and increase crop productivity by delivering the proper irrigation water to the right location on time.

14 772 Tenth International Water Technology Conference, IWTC , Alexandria, Egypt REFERENCES 1. Markham, B., and J.L. Barker, 1985, Spectral Characterization of Landsat Thematic Mapper Sensor, International Journal of Remote Sensing, Vol. 6, pp Soil, Water, and Environment Research Institute, Application of Remote Sensing to Soil Survey and Land Suitability Assessment Evaluation, Cairo, Egypt, Soil, Water, and Environment Research Institute, Application of Remote Sensing to Agriculture in Egypt, Final Report, Cairo, Egypt, Townshend, J.R., Agricultural Land - Cover Discrimination using Thematic Mapper Spectral Bands, International Journal of Remote Sensing, 5(4), pp , Food and Agriculture Organization of the United Nation (FAO), Use of High Resolution Satellite Data for Agricultural and Marine Applications in the Maldives, RSC series, No. 45, FAO, The Economic Affairs Sector (EAS), Agricultural Statistic Bulletin, Detailed data and statistics for 2001 Summer and Nili Crops, Ministry of Agriculture and Land Reclamation, Cairo, Egypt, Ismail, M., Master Thesis, Assesment of Remote Sensing Classification Techniques and Change Detection for Updating GIS Database, Civil Engineering Department, Faculty of Engineering, Cairo University, Cairo, Egypt, Attia, B., Egypt's Water Resources for Year 2000: an Overview, Water Science magazine, National Water Research Center, Cairo, Egypt, October David, S., Designing Water Resource Strategies for the Twenty-first Century, Discussion paper No. 16, Center for Economic Policy Studies, Winrock International Institute for Agricultural Development, Strategic Research Program (SRP) of the National Water Research Center and USAID Sponsored Project, SRP Publication Series No. 34-5, Revised Nile River Water Balance, Cairo, Egypt, Irrigation Sector, Daily Records of Discharge to Main Canals in 2001, Ministry of Water Resources and Irrigation, Cairo, Egypt, 2001.