Iranian National Committee on Irrigation and Drainage (IRNCID) has won the 7th BPNC Award. The award was received by Dr. Narges Zohrabi from President Prof. Dr. Ragab Ragab on the occasion of the 74th IEC Meeting and 25th ICID Congress held in Visakhapatnam (Vizag), India November 2023.

Rice production is not only equated with food security but political stability in many developing countries, where a significant majority of all rice is produced in Asia. It consumes nearly half of the entire world's irrigation water and around one-third of its freshwater. To meet the ever-increasing global demand, production must increase by 15% by 2050 while irrigation is expected to increase by 70 to 90% and to two to threefold by the end of the century. Asia will also be facing a maximum reduction of 40% of its water supply by 2025. As three-fourths of rice production is from water-intensive irrigated lowland conditions, more sustainable water-saving alternatives should be introduced to meet these sheer challenges.

Lowland rice cultivation has several advantages, such as seedlings quickly dealing with weeds and thus weed growth will be minimal [6] while puddled soil plays a vital role in reducing infiltration losses which decrease exponentially by increasing the intensity of puddling. Furthermore, a puddling environment helps cyanobacteria to provide nitrogen for the rice. However, only around 13-33 percent of the irrigation is used by transpiration and seepage and deep percolation account for 80 percent in this method. An alternative to reduce irrigation amount without significant yield loss [11] is Alternative Wetting and Drying (AWD) irrigation which is done by applying 2-5 cm of surface water on puddled soil for the period of 2-7 days after the disappearance of surface water. Another approach could be direct-seeded cultivation, the oldest method of planting rice, accounting for around 23% of rice cultivation globally. However, while water use is reportedly reduced by 55%, yield is reduced from 8 to 3.4 t ha-1. Longer land occupation, more weed control management, and large seed supply and fertilizer are other downsides of this method.

A recent approach is the drip irrigation of rice which provides moisture within the root zone, reduces evaporation and percolation, enables precise automation, fertigation and minimizes labor costs. Moreover, a study demonstrated that methane emissions decreased enormously, around 80% from drip irrigation of aerobic rice and this number was around 50% for the alternate wetting and drying, which shows that drip irrigation and AWD, despite their advantages, are more climate-friendly in terms of aggravating climate change. However, drip irrigation is mostly studied in aerobic rice cultivation and analyzing drip irrigation on transplanted rice in puddled paddy soil is rare to unknown. On the other hand, drip tape irrigation systems are known to be cheaper and easier to install and maintain than conventional drip irrigation with emitters. By having the benefits of rice transplantation, puddling and drip tape irrigation system, this study was conducted to comprehensively determine how this new approach will perform regarding water productivity and yield characteristics compared to AWD irrigation.

Experiments were conducted at the Rice Research Institute of Iran (RRII) for two consecutive years in 2020 and 2021 in Rasht. Twelve isolated concrete blocks (check basins) with dimensions of 3x5 meters were selected for four irrigation treatments, each with three replications as a split-plot experiment based on a complete randomized block design.

Three drip tape irrigation treatments with different lateral spacing of 40 cm (T40), 60 cm (T60), and 80 cm (T80) with 16 mm in diameter, emitter spaces of 20 cm, and a flow of 1.6 L hr1 compared with AWD irrigation by five days period (after surface water disappearance). The daily weather data was obtained from the institute's meteorological station within 450 meters of the plot. Evapotranspiration was calculated based on the evaporation data recorded from Class A Evaporation Pan at the meteorological site with a pan-crop coefficient (Kp.Kc) of 1.3, which is determined from previous local experiments. Tillage and puddling operations were carried out in mid-May inside the blocks, and seedlings of the Hashemi variant were transplanted in late May from the treasury by 20 to 20 cm. All treatments were flooded for two weeks ranging between three to five centimeters of water level. Following that, the laterals of the drip tape irrigation treatments were placed with two rows of seedlings in between T40, three rows for T60, and four rows on T80. In the first year, Irrigations were controlled by SMS remote controller and adjusted with effective rainfall based on FAO's formula. However, in 2021, irrigations were managed manually by technicians due to potential blackouts and better technical servicing. The irrigation rate is documented and checked from water meters on a daily basis.

The farm is located in Neyriz city in the east of Fars province. This city with an average rainfall (30 years) of 209 mm and annual evaporation of about 2280 mm has a temperate arid and semi-arid climate. The average minimum, maximum and annual temperatures are 13, 25 and 19.5 °C, respectively. Due to the climatic conditions of the city and the prevailing drought, water consumption management in the agricultural sector is of particular importance. In this regard, the project of increasing water economic productivity by selecting the optimal cultivation pattern in my farm has been underway since 2011. This farm with an area of 40 hectares is located in Balashahr village of Neyriz city. This project has six subprojects (Table 1) including:

1) Rain fed fig orchard construction (30 ha) with characteristics of high economic value, the ability to earn foreign currency, long life trees, high ability of job creation, and having fruits with long life and high nutritional and medicinal values.

2) Nursery creation with the purpose of promoting and developing this product in arid and semi-arid regions of the country, especially in sloping lands and to control soil erosion.

3) Creating walnut collection orchard containing 14 promising compatible and cultivars in order to improve yield of low-yield walnut orchards and convert the non-economic walnut orchards in the country to economic orchards.

4) Creation of a transplanted walnut nursery containing the world's top cultivars to increase walnut yield and make these cultivars compatible to the different climate conditions of Iran.

5 and 6) 1 hectare of apricot trees and wheat crops are still left on the farm.

Water Saving

The water source of the farm is a 2.6 km long qanat with an average discharge of 20 liters per second. My share from this qanat is 51 hours out of total of 288 hours of a 12-day irrigation cycle. Thus, the quota for the extracted volume of qanat water during a year is 111690 cubic meters. The volume of irrigation water for various subprojects is estimated at 41213 cubic meters per year; therefore, only 37% of the water quota has been used for these subprojects and the rest (63% of the water quota which is equal to 70365 m3 per year) have been used to feed the groundwater aquifers downstream during autumn and winter seasons. Figure 4 shows the amount of water used per month for different subprojects. As it is clear from this figure, in the winter season the entire qanat water has been used only for supplementary irrigation of the fig garden and other crops have been irrigated in the first eight months of the year. Therefore, in this farm and according to the subprojects income and cost data, the annual profit of the farm is 72932 million Rials and the productivity efficiency of water in the whole farm is 1.77 million Rials per cubic meter by considering the total water consumption. Therefore, in line with the goal of sustainable agriculture, on-farm irrigation management is optimal. During these 10 years, with the change of cultivation pattern from crops, especially wheat, to fig orchards, economic productivity has increased dramatically, so this index in figs is 24 times higher than that of wheat. This means that by cultivating fig trees instead of wheat, 24 times more profit can be obtained from 1 cubic meter of water.

Other measures taken to develop sustainable agriculture and save water that will be used on my farm in the near future are as follows:

• Construction of grape greenhouse at the area of 1.5 hectares of the world's top cultivars
• Establishment of a Capri fig orchard at the level of 2 hectares for supplying pollen to the orchards of the region
• Cultivation of Asafetida as a medicinal plant in 2 hectares

Darab township is located almost in the south of Iran, between 28 46? and 28 76? north latitude and 54 32? and 54 54? east longitude with an arid climate and an average annual rainfall of 270 mm. Darab is one of the major agricultural zones in Fars province, located between the plains and mountains, where groundwater resources mostly irrigate the arable lands. One of the challenges in this area is the low chemical quality of the water, along with the drop in groundwater levels. The chemical quality of groundwater in this flat is influenced by the salt domes, evaporation rate, and the direction of groundwater, which are the main factors affecting the water quality of the plains. Due to these conditions of Darab city and the 8-years drought situation, agricultural water management is critical. In this regard, since 2018, the plan of increasing the productivity of wheat-based systems with the approach of conservation agriculture and integrated water and soil management has been implemented. The educational research site of the farm with an area of 5 ha is located in Marian village of Darab city. 

Localisation principles and implementation of conservation agriculture based on crop management are among the most important innovations of this project. Besides, another goal is to generate knowledge and information to utilise conservation agriculture by expanding cooperation between stakeholders and forming teams with different specialities.

Water Saving through the Innovation

Conservation Agriculture (CA) is a sustainable package that alleviates soil erosion and greenhouse gases, enhances soil fertility and productivity, and has many other benefits. Generally, CA is a triple approach for agriculture that includes maintaining a permanent cover on the soil by crop residuals, practising no-tillage to reduce soil disturbance and dispersion, and using crop rotation to cut off the cycle of pests and improve soil fertility. In other words, CA is an approach to manage agricultural ecosystems that achieve sustainable agriculture by minimising soil disturbance and soil erosion, maintaining crop residues, and diversifying the crops. The primary purpose of conservation agriculture is to increase soil organic matter by preserving crop residue and soil moisture. For soil management, planting and cultivation methods are modified on wide, long, and fixed ridges to reduce machine traffic and minimise soil compaction due to increased soil physical properties. Preservation of at least 30% and at most 50% of crop residue at the surface of the ridges increased soil moisture and soil permeability. Increasing soil organic matter from 1.03 to 1.32% in two growing seasons has improved soil biological properties.

Other measures taken in conservation agriculture include proper and timely management of weeds and reducing competition in water consumption with the main plant, correction of crop rotation and adequate plant density per square meter.

Due to the installation of a water flow volume meter at the field entrance, the amount of water consumed was measured during the growing period. The results showed that due to the change of irrigation system from surface to tape, water consumption has decreased by 30%. In this project, the amount of water used for wheat was 3750 m³/ha. The measure of conservation agriculture and integrated water and soil management led to a 25% increase in wheat yield.

Implementation of the Innovation

The cultivation program of this educational research site has been developed on a 5-year plan. At the end of each cropping season, to promote conservation agriculture, training classes are held with experts and farmers in the cities of the Fars province. All technical reports of growing, harvesting, and packing have been published in the mass media. Separate lines and plots have been defined to compare different cultivars, machines, disease, and weed management. In these conditions, practical and technical comparison of conservation and traditional cultivation is feasible. Economic analysis and comparison of production costs under conservation cultivation and tillage under the surface and pressurised irrigation conditions have been performed.

Scope for Further Expansion of the Innovation

Most governments can apply various methods to use CA principles by farmers. Most methods can be classified into three categories: law and regulations, financial incentives, and farmers' voluntary behaviours. Utilising incentives and laws and regulations are methods that will have short-term effects. But, farmers' voluntary behaviours have long-term and positive impacts on sustainable agriculture, requiring a proper understanding of the farmers' willingness and ability to carry out sustainability activities. The learning transfer means applying the skills, knowledge, and attitudes gained from the training to a workplace in the direction of sustainability and environmental protection. In other words, learning transfer occurs when farmers apply sustainability skills, attitudes and knowledge learned from training to their farms. Learning transfer is a novel and relevant issue deployed in various fields. The learning transfer system helps recognise how farmers apply the learned skills and principles in farms. This study on this farm is novel because the level of farmers' learning transfer is denoted based on their characteristics.

The most crucial strategy for the development and dissemination of conservation agriculture in the future are:

• Informing political officials, Executive, research, extension, and local governments to develop better programs
• Cooperation of various research and executive departments, manufacturing companies at national, provincial, city and service centers.

A farming activity has a complex structure because it exploits living organisms in an uncertain environment, both bio-pedo-climatic and socio-economic. This extreme complexity has made the modelling of agricultural training difficult because it is unsure whether it will effectively reoccur in the same area and at the same time.

The Faizabad-MahVelat area in Khorasan Razavi province is one of the most important pomegranates producing regions in Iran; however, it has faced extreme weather, rising temperatures, and water scarcity in the last few years. To promote pomegranate production, a favorable environment was created by implementing a combination of several techniques.

The problem of water scarcity was solved with drip and subsurface irrigation technology. But high temperatures and direct sunlight on trees caused problems such as the trees not being able to absorb the water they need, the destruction of the natural moisture, the withering of the leaves, insufficient breathing, and an increase in water consumption.

Awnings were designed for pomegranate trees as well as steam generators in the field. Columns were installed in the row of trees supported with 60% density lace nets placed over them. This reduced the intense sunlight on the tree as well as balanced the temperature preventing the loss of moisture. The design of the columns and the selection of nets used were in line with regional conditions (the presence of severe seasonal winds) as well as experiments performed earlier to have the least imposed costs.

The dimensions of a block of pomegranate tree orchards were 160 m by 100 m. There were 24 rows of trees along 100 m and 40 rows of trees along 160 m. Awnings were implemented in the row of trees along the 100 m, and the share of each tree in the width was 4 m. In each row of 100 m, 5 columns with a distance of 25 m were installed.

The steps of the operation were as follows:

• Foundation of the columns in 5 rows of 100 m.
• Cutting profiles and scaffolding tubes according to the desired details by a skilled welder.
• Scaffolding columns buried in the foundation after concreting, and installing profiles i on the plate after the concrete has been set.
• Plastic nets as well as longitudinal strips of tarpaulin with the desired dimensions placed on both sides by tarpaulin strips along the length.
• Nets to be spaced every 30 cm and then connected with rivets.
• Cables are cut as per the required size and connected by clamps in the required places.
• To prevent buckling of the columns, the beginning and end columns to be restrained to the foundation.
• Cables laid on the columns along the entire row, stretched and restrained at the beginning and end of the foundation.
• Using scaffolding and footboard, the nets with a width of 3 m, to be installed with great precision and step by step on low-end cables.
• To prevent the nets from tearing due to strong winds, two cables are added to the grid installed along the length.
• With wire, each of the rings is to be mounted on the grid connected to the side cables.
• Finally, after installing the columns of the side rows, the columns are to be welded to each other through a scaffolding pipe so that the assembly is connected. Then, the stretched set of adjacent rows connect by a cable at every 7 m.

Water consumption was reduced to almost 50% using this management technique. Before running the project, each pomegranate tree needed about 300 LLL of water every 5 days, but after the project, the water requirement reached approximately 150 LLL in 8 days. It also led to increased irrigation periods. The project began with a 100 ha of pomegranate and pistachio orchard, and the awareness campaigns and experience-sharing activities were organized for the benefit of other gardeners in the area.

Pistachio Research Institute located in Rafsanjan city of Iran developed an innovative irrigation technique between 2011-2014 along with few gardeners, approved by the Institute of Technical Research and Engineering considering its positive results.

In this technique, water from the source of irrigation water supply (well or water storage pool) is transferred to pressurized pipes up to the garden using the pumping system and then poured into the pool by special valves. The water, coming out of the pressurized state, moves by the force of gravity based on the slope of the earth, inside the water pipes. Inside each pool, water pipes transport the water under the soil and around the roots of the trees. The ends of the discharge tubes are also open and are connected by a knee to a vertical tube (ventilator). This ventilator is responsible for discharging air into the pipe and facilitating the flow of water inside. Water pipes with different diameters (90 mm to 125 mm) are installed depending on the soil texture, length of rows, irrigation system flow, land slope on both sides of the row of trees, and at a certain depth from the soil surface (30 cm to 60 cm). The installation depth of the water pipes depends on the soil texture and is usually chosen to have the least amount of moisture on the soil surface to prevent surface water evaporation losses. If the distance between the rows of trees is less than 5 m, only one pipeline in the middle of the rows of trees is used. The distance of the pipes from the trunk of the tree also depends on the texture of the soil, the age of the plant, and the dimensions of the crown of pistachio trees and usually varies between 0.8 and 1.3 m. The length of the pipelines between 30 and 100 m is usually acceptable and is considered less in light soils (maximum 70 m). The diameter and distance of the holes on the pipes also depend on the texture of the soil, the planted trees rows’ length, and the amount of discharge entering each pipe. So, the diameter of the holes varies between 9 mm and 12 mm and their distance from each other varies between 15 cm to 35 cm.

Unlike micro?irrigation systems, in this technique, the heavier the soil, the larger the diameter of the holes, and the shorter the distance between the holes. Since a large volume of water must be distributed in a short time in the root zone of trees, the main holes responsible for distributing water in the soil, are placed at an angle of about 45 degrees to the line perpendicular to the floor of the pipe at a certain distance. Holes are also installed in the floor of the pipe one by one between the main holes to completely drain the pipe water. The inflow of water to each pipeline depends on factors such as pipe diameter, pipeline length, and soil texture and usually varies between 2-8 l/s. Around the tubes, a layer of gravel about 10 cm thick is placed as a filter. The diameter of the filter particles is usually between 6 mm and 12 mm. The filter is used on the bottom and sides of the pipe and there is no need for a filter on the pipe. This gravel layer prevents soil particles from entering the pipe, prevents soil leakage, creates a uniform environment for better water distribution along the pipeline, and prevents plant roots from entering the pipe. A layer of nylon on the pipes is used to prevent soil particles from entering the filter during winter leaching.

In addition to reducing water consumption, and increasing water use efficiency, the technique has 3 main advantages:

• Possibility of using it in saline waters due to its low sensitivity to clogging water outlets.
• Good adaptation to retail conditions due to the possibility of distributing large volumes of water in the root zone of garden trees in a short time.
• Possibility of reducing irrigation frequency in gardens with a high irrigation cycle.

First research work on this irrigation system resulted in a 25% reduction in water consumption (about 1,800 m³/ha) and a 62% increase in water use efficiency compared to flood irrigation. Additionally, depending on the planting distance of trees, it is possible to reduce water consumption by 50% compared to conventional flood irrigation in pistachio trees in the region. Another important advantage of this system over micro?irrigation systems is its good adaptation to micro?property conditions and the possibility to reduce the irrigation cycle in pistachio orchards with long irrigation frequency.

In the last few years, different installation depths of the pipe, the diameter of the pipe, and the diameter and distance of the holes on the pipes have been evaluated. In addition, the effect of the design on moisture distribution, and soil salinity were evaluated more accurately. Other complementary tasks included optimizing and manufacturing a special filter for round pipes or polyethylene prefabricated pools to facilitate the implementation of this irrigation system.

Soil erosion in Iran is very high, nearly 2.5 times more than the world average which impacts the agricultural output. This peculiar problem of soil erosion requires innovative irrigation techniques. One such technique is the placement of micro-dams in furrow irrigation which helped in reducing water and phosphorous losses and increased water-savings.

Despite the availability of modern irrigation methods globally, surface irrigation is still widely applied in agricultural lands, with furrow irrigation being one of the most common methods. Farmers in Iran also employed surface irrigation which reduced water flow velocity and runoff rate by placing soil or straw (as a barrier) inside irrigated furrows. However, this traditional operation has not been systematically investigated. Despite all the advantages, the open-end (free draining) furrow irrigation method has one disadvantage that when the water reaches the end of the field, it freely moves out of the field, and consequently dissolves matters and the eroded sediments are transferred out of the field. Phosphorus losses occur in surface irrigated fields by soil erosion released by runoff from the field. Eventually, it reduces the quality of downstream water resources. Therefore, an appropriate technique was developed to control soil erosion and water losses.

The presented technique is the creation of micro-dams inside the irrigated furrows. It effectively reduces surface water velocity, soil erosion, and run-off and phosphorus losses from the agricultural fields. The low cost of micro-dams and the simplicity of their construction are the prime advantages of this technique. A field study observed the effects of these micro-dams. Field studies and experiments were conducted at the College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran. The soil texture was clay loam and the farm’s slope was 0.96%. Measurements were carried out in four irrigation events at the beginning of the season. In this study, the combination of two erosive inflow discharges (0.6 and 0.9 l/s) and two micro-dam distances along the furrow (20 and 10 m) was investigated. A control treatment (a furrow without micro-dams) was used for each experimental discharge. Therefore, six treatments were established. Consequently, 24 irrigation evaluations were performed. Super Phosphate (Ca(H₂PO₄)₂H₂O) fertilizer was applied for providing phosphorus. The amount of pure phosphorus added to the soil was 40 kg/ha. After fertilization, experimental furrows with a length of 100 m and a spacing of 0.75 m were created by the furrower machine. The experiment required 18 contiguous furrows. Micro-dams were manually built to create a 0.05 m hump above the average local furrow base elevation. Furthermore, the micro-dams were covered with plastic film for preventing their destruction by overflowing water. In control and treatment furrows, inflow and outflow discharges were measured using WSC Type 1 flume, and the amount of erosion and phosphorus losses were determined by runoff sampling at different periods. The concentration of phosphorus in the runoff water sample was measured by a spectrophotometer device.

Micro-dams substantially reduced the runoff, runoff sediments, and phosphorus losses when compared to the control treatments. The increase in discharge increased flow velocity and the furrow wetter perimeter, and consequently increased runoff and sediment losses for all treatments and irrigation events. In addition, micro-dams were more effective in controlling erosion in the high inflow discharge treatments. The effectiveness of micro-dams in controlling erosion at large inflow discharges was an important finding, suggesting that this technique can be adequate for sloping areas where the soil is prone to erosion. Also, phosphorus losses were higher for higher discharge, indicating that phosphorous losses may be very sensitive to inflow discharge. Since phosphorus is attached to soil particles, an increase in soil loss causes increased phosphorus losses in runoff.

Compared to the control treatment, the following reduction in the amount of runoff, runoff sediment, and phosphorus loss was observed for micro-dams with distances of 20 m and 10 m, respectively.

• For micro-dam spacing – 10 m and inflow rate 0.6 l/s – Runoff decreased by 45.4% in the first irrigation event and by 32.3% on the average of the four irrigation events
• For micro-dam spacing – 10 m and inflow rate 0.9 l/s – Runoff decreased by 37.4% in the first irrigation event and by 24.5% on the average of the four irrigation events
• For micro-dam spacing – 20 m and inflow rates of 0.6 and 0.9 l/s – Runoff reduced by 26.7% and 17.9% respectively, compared to the control treatments.
• In the absence of micro-dams, the sediment losses in the discharge of 0.9 l/s were 69% higher than in the discharge of 0.6 l/s.
• For discharge of 0.6 l/s, reduction in runoff sediments – 25.2% (20 m distance) and 33.0% (10 m distance).
• For discharge of 0.9 l/s, reduction in runoff sediments – 25.3% (20 m distance) and 59.5% (10 m distance).
• For inflow discharges of 0.6 l/s and 0.9 l/s, micro-dams spaced 10 m significantly reduced erosion (p-value <0.05).
• For discharge of 0.6 l/s, reduction in phosphorus losses – 12.9% (20 m distance) and 32.2% (10 m distance).
• For discharge of 0.9 l/s, reduction in phosphorus losses – 24.1% (20 m distance) and 37.4% (10 m distance).

Observation: Micro-dam in the furrow stored and saved water in two ways. In the first stage, the micro-dam reduced irrigation runoff losses from the field and subsequently led to saving water. The results of this study indicated that micro-dams in furrows reduced 45.3% of total runoff from the field. Secondly, the micro-dam also provided non-direct storage of available water resources by preventing the transporting of fertilizer to downstream water resources and contaminating them, thus preserving the quality of water resources. Micro-dams in-furrow reduced soil erosion up to 59.5%, and also prevented the loss of phosphorus up to 37.4% in comparison with the control treatment.

Future studies on this topic could focus on modifying a furrowing machine for creating micro-dams to reduce labour costs, optimizing micro-dam design for different inflow discharges, soil textures, and field slopes, and establishing the economic implications of micro-dams in different open-end furrow irrigated agricultural production systems.

Traditionally, the animal waste residue has been used as a fuel in Iranian rural areas in furnaces, baking ovens, heaters to provide heat and energy. The ashes produced from the burning mainly consist of a silica compound, which is called "Koul” (in local language) and has structural differences with charcoal ash. Due to limited research on the use of koul, an experiment was conducted to understand the various uses of this type of ash.

This project was implemented in Ghani Beigloo Village, Zanjanrood Department of Zanjan, in 3 blocks and 12 plots. The area of each plot was 2.25 m². The number of treatments was selected based on the most effective amount proposed in the sources.

In three types of clay-loam, sandy-loam, and clay soil texture, 3 treatments weighing 10, 20, and 30 ton/ha of ash were added to the clay-loam soil texture to test the percentage of moisture content, the average rate of water penetration in soil and basic penetration rate. At first, a soil sample was taken from a depth of 0-30 cm and soil texture was determined according to the standard hydrometric method - ASTM D422-63. Then, the percentage moisture content of each plot was calculated based on the standard moisture content determination test, AASHTO-T73-293, ASTM D2216-71, and the resulting data were analysed. A detailed analysis of the experiment is presented below:

Determining the percentage of moisture content: The percentage of soil moisture content was calculated to determine the exact time to irrigate plants according to the plant’s water requirement. Compared to the control treatment, in clay loam soil, the water penetration rate of soil was increased in treatments of 10 and 20 ton/ha of ash but in the treatment of 30 ton/ha, the penetration decreased due to the reduction of effective porosity of the soil. In loam sandy soil, Koul had little effect in the treatment of 10 ton/ha and showed a decrease of penetration rate in 20 and 30 ton/ha. (Presented in Table 3.1)

Different soil textures require different treatments for maximum moisture content in the depth zone of 0-30 cm. In all three treatments in clay soil (10, 20, and 30 ton/ha of ash) an increase in moisture content in weight percentage compared to the control sample was observed. The overall result of this test showed the positive effect of ash on water retention.

To measure the infiltration, instructions for measuring water penetration rate were used in the double-ring field method from Iran's water industry standard (1981- A-84). Based on these instructions, two cylinders with a diameter of 30 and 60 cm and a height of 30 cm in form of concentric were hammered inside the plot and the permeability was measured with accuracy. To estimate the amount of water penetration into the soil and its changes with time in different soil textures and climatic conditions, the Lewis-Kostiakov equation was used and results were found to be satisfactory.

Determination of the average penetration rate of water in the soil

In the experiments conducted on different treatments, the average penetration rate of water to soil was studied. The results showed that 10 ton/ha of ash had no effect on loam clay soil, but 20 ton/ha increased the permeability, which showed a positive impact on the ash. In the 30 tons treatment, the average penetration rate of water to soil was reduced, the reason could be the loss of effective porosity of the soil. Also, koul decreased the permeability of Loam Sandy soil at 10 and 20 ton/ha, while at 30 ton/ha increased the average permeation velocity. In clay soil, as the ash increased, the average permeability rate increased, but the process was stopped at 30 ton/ha. (Presented in Table 3.2) Table 3.2 Average penetration rate (cm / h)

The water penetration rate in the soil:

Compared to the control treatment, in clay loam soil, the water penetration rate of soil increased in treatments of 10 and 20 ton/ha of ash but in the treatment of 30 ton/ha, the penetration has decreased due to the reduction of effective porosity of the soil. In loam sandy soil, koul had a little effect in the treatment of 10 ton/ha and showed a decrease of penetration rate in 20 and 30 ton/h of ash. (Presented in Tables 3.3) Table 3.3 The rate of penetration of the water in the soil

The treatment of soil with ash was tested on 1-ha of apple orchard. The conventional growth period was 175 days with an average irrigation interval of 6 days requiring 10,460 m³ of irrigation water along with a pre-irrigation requirement of 30 mm water depth. Each irrigation cycle consumes 431 m³ of water. Loamy-clay soil was treated with 20 ton/ha of ash based on the experiments and the overall moisture penetration.

Increasing the irrigation interval from 6 to 8 days, along with treatment of soil by adding 20 ton of Koul (ash), eliminated eight irrigation cycles from the irrigation plan (saving about 3,448 m³ of water). At the end of the period, an increase in yield, due to an increase in irrigation efficiency was observed. Thus, about 27% of the water in the growing period could be saved by treating the soil with Koul.

The total area under cultivation of horticultural and crop products in Zanjan province is about 1,86,000 ha, which consumes 1.5 BCM of water each year. Considering the access and availability of Koul, a bare minimum of 10% water can be saved amounting to 150 MCM annually. The use of this method is very cost-effective and will be beneficial for farmers, especially in drought-affected areas. It can be used in the greenhouse cultivation phase as well as in rain feed cultivation for a variety of crops and treatments.

Water scarcity along with non-accurate measurements of crop water requirements create serious problems for agricultural water management in arid and semi-arid regions. There was a need to develop low-cost equipment that works with precision, simplicity, and results in water-saving.

Based on the requirement a drainage-weighted micro-lysimeter was designed. It was developed for its simplicity and accurate measurement of crop water requirements based on the water and soil balance equation. Due consideration was given to available and relatively inexpensive equipment compared with the two common measuring methods (theta probes and pan evaporation methods. The results under indoor conditions (greenhouse), outdoor conditions (pot study), and in-field conditions were investigated and the benefits of this method in field conditions over the other two measurement methods were proven.

Micro-lysimeters used three 10-l buckets and one drainage hole. A thick domestic hose from each bucket was passed through the hole and connected to a small bucket with a lid. Then the buckets were filled with one layer of coarse sand soil 3 cm thick and were passed through a 200 mm sieve as shown in Figure 3.10.

After comparing the three measurement methods with each other, a pot level study was conducted in a 1-ha experimental field with irrigation management scenarios including full irrigation treatment (FI) and three deficit irrigation treatments (DI 80%, DI 60%, and DI 40%) at 100%, 80%, 60% and 40% of crop water requirement based on the percentage of mean full crop water requirement of micro-lysimeters respectively in two agronomical years 2015 and 2016. During the entire growing season, every 12 hours (6 am and 6 pm) micro-lysimeters and the drainage water content was collected and weighed, and the drained water quality was measured using a portable EC meter. This method for estimating crop water requirement was done based on water and soil balance; the theta probes method was based on the soil moisture deficit compensation method, and the third method was based on measuring evaporation from class-A pan evaporation method from the local synoptic station (Doshan Tappeh station) (Figures 3.11).

In micro-lysimeter and theta probes methods, the amount of crop-absorbable moisture was calculated and then irrigation was applied when the moisture reached that level. The depth of irrigation water was determined. The rate of maximum available depletion (MAD) was considered to be 30%. The amount of crop water requirement was calculated by using the soil and water balance equation. In class-A pan evaporation method, daily climatic data were used to calculate reference evapotranspiration (ET_O) by FAO-Penman-Monteith equation. Crop coefficient (K_C) was determined using ET_C obtained by micro-lysimeter and ET_O obtained using FAO-P-M reference evapotranspiration.

It was found that micro-lysimeter saved about 10% of the irrigation water compared to Class A pan evaporation and Theta probe. This technique can prove to be beneficial in water-deprived areas that have limited facilities. The measurement of basil evapotranspiration showed that against a maximum of 545.8 mm with Class A pan evaporation micro lysimeter had 490.74 mm. The corresponding average values were 545.447 and 498.317 mm and basil yield in g/pot indicated that under theta probe the maximum yield was 65.7 whereas under micro lysimeter it went up to 71.3 g/pot. The corresponding average values are 65.07 and 68.62 g/pot. Despite the reduction in water consumption in the micro-lysimeter, crop yield was increased by about 10%. The results indicated that drainage-weighed micro-lysimeter reduced crop water requirement than evaporation pan and the theta probes methods based on T-test and other observed data.

This experiment demonstrates four important implications for sustainable farm water use in arid and semi-arid regions. This technology is low-cost and does not require a minimum standard area. Unlike, evaporation pan and theta probes methods, which require data gathering, and data recording as well as complex measurements, micro-lysimeter preparation is easy to learn and implement. Moreover, the accuracy of theta probes set depends on soil type and is recommended for sandy soils but this micro-lysimeter can be used in all types of soil textures. The need for estimating actual crop water requirements for suitable irrigation scheduling to achieve maximum crop yield with the optimum water consumption in arid and semi-arid regions has been demonstrated using lysimeter in terms of water-saving up to 10%, increase in crop yield up to 10%, cost-effectiveness and ease of use.

Iranian National Committee on Irrigation and Drainage (IRNCID) has won the 6th BPNC Award. The award was received by IRNCID representative from President Dr. Saeed Nairizi on the occasion of the 68th IEC Meeting and 23rd ICID Congress held at Mexico City, Mexico, October 2017.

Keywords: water leak detection; airborne remote sensing; multispectral imaging; irrigation distribution network; canal leakage; field reconnaissance; thermal imagery; normalized difference vegetation index

Presented at: 62nd IEC Meeting 2011, Tehran, Iran

Iranian National Committee on Irrigation and Drainage (IRNCID) has won the 3rd BPNC Award. The award was presented to IRNCID by the Governor of Punjab on 17 October 2008 on the occasion of the 59th IEC and 20th ICID Congress held at Lahore, Pakistan.