eChapters

Participatory water management, principles of sustainable farming and crop water productivity and strategic water management practices
Participatory irrigation management
Farmers’ participation in management of water resources is one of the prime requirements to improve the irrigation efficiency and enhance food production to meet the future requirement. The objectives participatory irrigation management (PIM) are to achieve equity in water distribution, make best use of rain, surface and ground water conjunctively, develop community responsibility to collect water charges and create a sense of ownership of water resources and the irrigation system among the users so as to promote economy in water use and preservation of system, improve service deliveries through better operation and maintenance and achieve optimum utilization of available resources.
Participation of farmers in the realm or irrigation water management implies an active role of beneficiaries in all the facets of irrigation water management and its attendant linkages with the main system of management in agricultural/agronomic activities. This role is very different from the traditional passive role of farmers to look to the department for irrigation, for water supply and its distribution. The timing of farmers’ involvement is crucial. Farmers’ participation is most effective, when it takes place from initial stages of project planning, including the stage of project formulation. Such involvement forms part of ideal conditions for a partnership between farmers and government. The present theme “more crops per drop” is feasible provided the farmers are encouraged and supported to play an active role in the operation and management of the irrigation system. However, to operationalize this concept, there is a need to involve all the farmers within the command area, so that collective and collaborative action becomes possible.
Importance of Participatory Water Management
The per-capita availability of cultivable land as well as water is going to be stagnated, wherein irrigation is the only key factor leading to increased

Introduction
Surface irrigation is the distribution of water using open canals in which water flows by gravity. This type of irrigation, which includes flood irrigation, requires relatively flat fields and deep soils.
A good irrigation will ensure a uniform and homogenous distribution of water in small and regular doses. The status of moisture in the soil also aims at maintaining the relative humidity in a plot at a stable level, to limit the development of weeds and pathogens. Irrigation is also used to avoid the transmission of phyto-sanitary problems or the leaching of pesticides.
The volumes of water to apply depend on the climatic conditions, the frequencies of the applications, the soil type and the irrigation method. The choice must take into account the efficiency of each method, the water availability, the installation and running costs, the maintenance needs, the spatial requirements and whether it’s possible to work while the field is irrigated.
Water Management Practices of Different Crops Rice
Total water requirement is 1100-1250
The daily consumptive use of rice varies from 6-10 mm and total water is ranges from 1100 to 1250 mm depending upon the agro climatic situation. Of

Principle of field drainage and methods of drainage, Benefits of drainage
Biological drainage
Importance of bio-drainage in water logged conditions
Bio-drainage and soil salinity
Agricultural Drainage
Excess water in the crop root zone soil is injurious to plant growth. Artificial drainage is essential on poorly drained agricultural fields to provide optimum air and salt environments in the root zone. Crop yields are drastically reduced on poorly drained soils, and, in cases of prolonged waterlogging, plants eventually die due to a lack of oxygen in the root zone. Waterlogging in irrigated regions may result in excess soil salinity, i.e., the accumulation of salts in the plant root zone.
Sources of excess soil water that result in high water tables include: high precipitation in humid regions; surplus irrigation water and canal seepage in the irrigated lands; and artesian pressure. Agricultural drainage is the removal of excess water from the soil surface and/or soil profile of cropland, by either gravity or artificial means. In some soils, the natural drainage processes are sufficient for growth and production of agricultural crops, but in many other soils, artificial drainage is needed for efficient agricultural production.
Agricultural drainage improvement can help reduce the year-to-year variability in crop yield, which helps reduce the risks associated with the production of abundant, high quality, affordable food. Improved access of farm equipment to the field provides more time for field activities, can help extend the crop production season, and helps reduce crop damage at harvest.
Agricultural drainage conditions around the world can be grouped according to three agro-climatic zones: the temperate zone, the arid and semi-arid zone and the humid and sub-humid zone.
In the temperate agro-climatic zone the major role of drainage is to prevent waterlogging, i.e., excess water in the root zone of crops from surplus rainfall.

Water Quality Parameters
Irrigation water contains impurities in varying concentration. The suitability of irrigation water mainly depends up on the amount and type of salts present in the water. The main soluble constituents are calcium, magnesium, sodium as cations and chloride, sulphate, bicarbonates as anions. The other ions present in minute quantities are boron, selenium, molybdenum and fluorine which are harmful to animals fed on plants grown with excess of these ions.
Quality of irrigation water is judged with three parameters
1. Total salt concentration
2. Sodium absorption
3. Bicarbonate and boron content.
Total Salt Concentration
Salt content of irrigation water is measured as electrical conductivity (EC). Conventionally, water containing total dissolved salts to the extent of more than 1.5m mhos /cm has been classified as saline. Saline waters are those which have sodium chloride as predominant salt. Brackish water is one that is contaminated with acid, bases, salts or organic matter, whereas saline water contains mainly dissolved salts, Based on EC irrigation water is classified as below.

Soil moisture stress in relation to crop and development of crop
Agronomic methods are supported with mechanical measures where land slope exceeds permissible limits and runoff gains erosive velocities. The following boxes explain the nature of agronomic measures which are essential in inter-bunded or terraced areas. These practices enhance the utility value of all kinds of mechanical structures.
1. Contour Tillage: All agricultural operations such as ridging, ploughing, harrowing, sowing, trenching, etc., are recommended to be done on the contour wherever possible or at least generally across the direction of the slope where holdings are very small. Even though the operation is very simple, it plays a major role in retarding the process of soil erosion through runoff. It also conserves soil, and due to increased time of concentration, more rainwater seeps through the soil profile to recharge ground water. Summer ploughing leaves the soil highly absorbent of initial rains.
2. Dead furrows: When all tillage operations are complete, it is advisable to leave a deep dead furrow at every 10 m interval. This should remain in position until the crop is harvested. Dead furrows aid in reducing the runoff velocity and they also conserve water.
3. Organic Matter: Indian soils are very poor in organic matter, especially in drought-prone areas: This can be improved by leaving the crop residue in situ (on the fields). Adding organic manures such as farmyard manure and compost every year as basal application to the soil improves the physical condition of the soil considerably.
Soil-Air, Soil-Temperature, and Soil-Moisture relationships are well balanced with the presence of organic matter. Organic matter improves the activities of soil microorganisms and also provides the much needed micro plant nutrients of all kinds, besides nitrogen, phosphorus and potash. Addition of large amounts of chemical fertilizers to dryland crops should be discouraged as it damages the soil due to:

Water Quantity and Measurement: The amount of water to be applied and its measurement are crucial aspects of irrigation management. There are various methods and tools used to measure and control the flow of water, including:
1. Parshall flume
2. Orifice
3. Weirs
4. Water meter
5. Float method
6. V-Notch
Methods of Soil Moisture Measurement
The measurement of soil moisture is essential to determine when to irrigate, the amount of water needed, to evaluate evapotranspiration, and to monitor soil matric potential. Soil moisture is measured in two ways: direct and indirect methods.
Direct Methods
1. Gravimetric method: The gravimetric method is a standard method for measuring soil water content directly. It involves collecting soil samples from the field and determining their moist and dry weights. The mass water content is then calculated as the ratio of the weight loss in drying to the dry weight of the soil sample. This method is accurate but time-consuming and requires laboratory equipment.
2. Spirit burning method: The spirit burning method is a direct method for measuring soil moisture in the field. Soil moisture is evaporated by adding alcohol and igniting it. The time taken for the soil to dry is then used to calculate the soil moisture content. This method is quick and easy but can be affected by soil temperature and organic matter content.

Irrigation Efficiency
Irrigation water is an expansive input and has to be used very efficiently. The main losses that occur during irrigation of fields as conveyance, run off, seepage and deep percolation; Irrigation efficiency can be increased by reducing these losses. Uneven spreading and inadequate filling of root zone are the other causes for low irrigation efficiency. Irrigation efficiency at the field level can be increased by selecting suitable method of irrigation, adequate land preparation and engaging an efficient irrigator. At the project level, it can be increased by proper conveyance and distribution system. Irrigation efficiency is the ratio usually expressed as percent of the volume of irrigation water transpired by plants, plus that evaporate from the soil, plus that necessary to regulate the salt concentration in the soil solution and that used by plants in building plant tissue to total volume of water diverted, stored or pumped for irrigation.
Wt+Ws-RsEi=×100Wi
Where,
Ei = Irrigation efficiency (percent)
Wt = the volume of irrigation water / unit area of land transpired by plants, evaporation from the soil during the crop period.
Ws = the volume of irrigation water per unit area of land to regulate the salt Content of soil solution.

Surface: border strip, furrow, basin and check basin
Sub-surface
Micro-irrigation: drip, sprinkler; Pichter and bottle
Definition of Irrigation Method
Application of irrigation water to cropped field by different types of layouts is called as irrigation methods. The methods of irrigation initially might have been started to check the over flow of water from one field to another. But today, it has become necessary to save the water by proper methods to arrest run-off loss, percolation loss, evaporation loss etc., and to optimize the crop water need. Hence, irrigation method can be defined as the way in which the water is applied to the cropped field without much application and other losses, with an objective of applying water effectively to facilitate better environment for crop growth.
Factors Influencing Irrigation Methods
Soil type: The soil physical properties such as texture, structure, porosity, infiltration rate, etc. influence the selection of irrigation methods. Heavy texture soil restricts water movement than light texture soil wherein water move freely to deeper sections due to high porosity. Single grain structure soil allows water freely to move downward compared to other structures
Soil depth: If soil is shallow which holds less water, leveling and forming bunds etc. to hold? Maximum water is to increase the irrigation interval. Similarly if the soil is deep, it holds more water and needs longer irrigation interval. Accordingly, the irrigation methods can be selected.
Topography of land: In undulating topography, it is very difficult to adopt normal methods of irrigation. The slope of the land also decides the methods to be adopted. If the land is more sloppy, basin method cannot be used. In this condition strip method can be used. For undulating topography instead of strip or basin method, sprinkler or drip methods can be used.

Irrigation Scheduling: Approaches and Advantages
Efficient irrigation scheduling aims to optimize crop yields while maximizing water use efficiency and minimizing soil damage. This involves determining the correct timing and amount of water to apply for each irrigation event. Several criteria can be used for scheduling irrigations, broadly classified into climatological, soil water regime, and plant-based approaches. The most suitable criterion depends on specific soil, plant, climate, and management factors.
Climatological Approach
Under conditions where soil water is readily available, the potential rate of water loss from a crop primarily depends on the atmosphere’s evaporative demand. This approach uses potential evapotranspiration (PET) or cumulative pan evaporation (CPE) over short periods as an index for irrigation scheduling.
Penman (1948) defined PET as the water transpired by a short, uniformly green crop completely covering the ground and never lacking water. He also noted that PET is generally a fraction of pan evaporation under the same conditions. PET can be estimated using various techniques, including lysimeters, energy balance calculations, aerodynamic approaches, and empirical formulas. Based on PET or crop water use rates over short periods, irrigation can be conveniently scheduled. Lysimeters isolate the crop root zone, allowing accurate determination of water balance components by controlling and measuring difficult-to-assess processes.
Soil Water Regime Approach
This approach uses the available soil water held between field capacity and the permanent wilting point in the effective crop root zone as a guide for irrigation scheduling. Soil moisture tension, which reflects how tightly water is held by soil particles, can also serve as an indicator.

Rice farming under different subsystems of lowland ecology
1. Rainfed lowland with limited water at seeding and excess water at later growth stages: In rainfed lowland areas, the rice is direct seeded in dry soil in April-May before onset of monsoon (June) and seeds germinate with the showers received after sowing. Drought at the seedling stage kills seedlings and results in poor stand establishment. Furthermore, heavy rains in catchment areas of river basins result in water logging and flooding at late growth stages. The water hinders tillering and results in poor panicle number less than 200/m2 as against 350 /m2 of high yielding rice cultivars.
2. Rainfed lowlands with limited/excess water at transplanting and excess water at later stages: When on-set of the monsoon is delayed, transplanting delayed because the farmer has to wait for adequate rains for land preparation. Monsoon rain submerges the transplanted crop, resulting in poor stand. In some areas, the land gets inundated before transplanting and farmers generally transplant aged and tall seedlings to keep the plant parts above the water. Plant survival in deeper water depends on rise in water level and on the elongation ability and submergence tolerance of the plant. Varieties that elongate fast develop weak culms and may lodge when the water level recedes. In this situation tillering is poor and panicle per unit area are less.
3. Assured irrigated areas with excess water during crop growth due to poorly drained condition: Rice grown in the river deltaic areas of Krishna, Godavari and Indo-Gangetic rivers suffer from water stagnation even though some areas are having irrigation facilities. Heavy rains in the catchment cause flooding and stagnation in rice fields because of congested drainage or lack of drainage caused by topographically saucer-shaped land. These conditions develop during peak monsoon (July-September). The late planted crops, being at an early stage of growth, suffersfro water stagnation. In these areas, transplanting early in the season is necessary for plants to grow enough to escape submergence.

Introduction
India is the seventh largest having 329.73 million ha of geographical area and second most populous country having more than a billion population in the world. There is no other substitute other than to use every square inch of land and every drop of water effectively and efficiently. Though there was markedly increase in annual food grain production from 51 (1950-51) million tones t0 206 million tones (2000-01), still the death on hunger is visualized.
The demand for food is increasing with ever-increasing population growth rate. So there is no option other than to increase food production. There is very little or no scope of horizontal expansion due to land limitation, the question of vertical expansion is the only way to fit with the situation. Genetically improved crop variety, hybrids, mechanized agriculture, higher rate of fertilizers and chemicals application may give one or two more green revolution, but the question lies how far it can sustain greenness?
Adoption of improved crop cultivars, cropping system, increasing cropping intensities, precision farming can hold good to get out of this situation where whole system is to be considered.
The cropping intensities in the states like Assam, Bihar, MP, Orissa, UP and West Bengal are 137.7, 137.8, 125.6, 154.6, 148.6 and 159.6 percent, respectively (FAI,1994-95). This indicated that a vast majority of lands remain fallow during dry season due to lack of proper technologies, which are under rainfed conditions, neglected. Except West Bengal, more than half of the arable land remains fallow during rainless period. Increasing cropping intensities in rainfed uplands is not easily achievable but there is great potential of intensification of cropping in rainfed lowland by utilizing natural resources and conserved residual moisture. Pulses like black gram, green gram, lentil, lathyrus, chick pea and oilseeds like linseed, groundnut, rapeseed could not only increase the cropping intensities but also come forward to increase national productivity.

Water budgeting and its importance, methods of soil moisture estimation, evapo-transpiration and crop water requirement and effective rainfall Water budgeting and its importance, irrigation scheduling approaches
Water budgeting
Allocation of the water receipt including anticipated within the crop period and its detailed account of expenditure for efficient and profitable farm management is called as water budgeting.
Water budgeting may be for an irrigation system planned by irrigation engineers; may be for a canal or for an area (block) or may be for a farm according to the need and plan by responsible persons who plan the irrigation efficiency.
Importance of water budgeting
Efficient utilization of available recourse (water) for bringing more area under irrigation:
1. To increase the productivity of a region / farm.
2. To increase cropping intensity of a region / farm
3. To tide over some dry-spells
4. To reduce excess irrigation and losses caused thereby
5. To avoid run off losses
Irrigation scheduling
Irrigation scheduling is defined as frequency with which water is to be applied based on needs of the crop and nature of the soil.
Irrigation scheduling is nothing but number of irrigations & their frequency required to meet the crop water requirement.

Different kinds of soil water and soil water movement; Water in relation to plant growth and crop production; Soil texture, structure, infiltration and permeability; Bulk density and particle density of the soil; Concept and theories of water retention in soils; Consumptive use and ET; Soil moisture characteristics curves; Different losses of water (seepage and run off) and Soil moisture measurement, stress and plant growth
Soil-Water-Plant Relationships and Irrigation Scheduling Concepts
A good understanding of soil-water-plant relationships is the foundation for understanding irrigation concepts.
Water reaches the soil through irrigation, precipitation, or from groundwater drawn up into the root zone through “capillary action”. To be available to plants, it must be held by the soil strongly enough so it is not lost to gravity before the plant gets it, but not so strongly that the plant cannot extract it from the soil. At the same time, the roots must have sufficient aeration to function properly.
Roots are responsible for obtaining almost all of the plant’s water and nutrients. These substances move through the soil during and after irrigation/fertigation and rainfall. In addition, root systems are continually growing and branching to seek out water and nutrients. Root hairs are very fine structures that extend at right angles to the roots. Water and nutrients predominantly enter the root system via specialized cells near the tips of root hairs.
The xylem is the cellular pathway through the plant that transports water from the roots to the leaves for use in photosynthesis and to cool the plant by evaporation. The process by which water vapour is released to the atmosphere by the leaves and other parts of a living plant, resulting in evaporative cooling, is called transpiration. The xylem also transports water and nutrients to other parts of the plant. In a living plant, the xylem is completely filled with water, just as the veins and arteries of the human circulatory system are filled with blood. The plant needs a continual replacement of water lost through transpiration to keep the xylem full of water, and of course, this has to be accomplished without an organ analogous to a human heart. Tomato plants

Soil physical properties
The physical properties of soil, particularly its mechanical behavior, significantly impact its suitability for plant growth. Factors like plant support, root penetration, drainage, aeration, moisture retention, and nutrient availability are all influenced by the soil’s physical condition. These properties also affect the soil’s chemical and biological activities.
A soil’s physical properties are determined by the quantity, size, shape, arrangement, and mineral composition of its particles, as well as its organic matter content and pore spaces.
Important Physical Properties of Soils
1. Soil Texture
2. Soil Structure
3. Surface Area
4. Soil Density
5. Soil Porosity
6. Soil Color
7. Soil Consistence
Soil Texture
Definition
Soil texture refers to the relative proportions of different-sized particles, specifically the percentage by weight of sand, silt, and clay. It’s a fundamental soil property that is difficult to alter. Soil textural determinations typically exclude particles larger than 2 mm in diameter (stones and gravels). While larger particles can affect land management and tillage, they contribute minimally to water-holding capacity (WHC) and nutrient storage/supply.

Water Resources: Classifications of water: Groundwater, surface water and Virtual Water; Conjunctive use of water in agriculture; Water resources in different states and Stakeholders of water use.
Introduction
Despite fact that more than two-third of the earth’s surface is covered with water, currently, near about 450 million people in 29 countries are facing severe water shortage and at least 20 percent more water would be required to feed additional 3 billion populations by 2025. About 97.5 percent of ocean-sea water is not available due to its salinity and 2.49 percent is locked up in ice and only 0.01 percent is technologically available and economically accessible water either from surface or ground water sources for human uses. So water saving technologies developed so far is very pertinent to propagate amongst the users. Water is an essential natural resource for sustaining the environment and supporting life where the agriculture is the major user of water resource. Water is an indispensable for sustainable agricultural growth and development. Previously, rainfed agriculture was associated primarily with conservational land treatments to check soil erosion and land degradation.But in the areas of medium to heavy rainfall, there is ample scope of tapping excess rain water through suitable water harvesting structures constructed for this purpose for its subsequent uses as irrigation or to apply lifesaving irrigation to the crops which should also come under the purview of water management for crop production. Although there is a difference in the objectives of water management where there is abundant availability of water from continuous flow connected with perennial sources or lakes and rivers and that of from restricted or limited supply from collection of excess rain through water harvesting structures.The former is associated with to obtain as much as yield of crop per unit area under water application and later is associated with increasing productivityof crop per unit of water application even under rainwater recycling and its effective management for the purpose of irrigation. Hence, both the rainwater and irrigation water are considered to be equally important to context of

Irrigation: definition and objectives; Importance: Function of water for plant growth, water resources and irrigation development for different crops in India.
Introduction
The effect of supplemental water application as irrigation for crop production at its needs during rainless period is well established throughout the world. The plant has life, so it requires water for growth and development to give us proper quality and good yield. Water is required for metabolic activities including solubilization, absorption and translocation on the way of biochemical processes in photosynthesis, transpiration and respiration. India with 2.4% of the world’s total area has 16% of the world’s population; but has only 4% of the total available fresh water. This clearly indicates the need for water resource development, conservation, and optimum use.
Importance of irrigation water management
The importance of irrigation in the world is well stated “Irrigation in many countries including India is an age-old art–as old as civilization – but for the whole world it is a modern science–science of survival”. The pressure of survival and the need for additional food supplies are necessitating a rapid expansion of irrigation throughout the world including India. Production and productivity of agricultural lands is primarily dependent upon the availability of irrigation water to crops. Expansion of irrigation has paid rich dividends in India. fter independence, production registered nearly 4.52 times increase from around 50.8 million tons in 1950-51 to about 230 million tons in 2007-08. This has been mainly attributed to three factors viz., high yielding cereals, expansion of area under irrigation and fertilizer use. Irrigation may be considered as the major factor of modern intensive agriculture as it aids in efficient use of costly fertilizers and other inputs besides meeting crop water needs.

Procedure
1. Mix the dough with ingredients I. Keep it for fermentation till breaks easily without stretching.
2. Put the sponge to mixer. Add salt, sugar, flour and optional ingredients and mix. In last, add shortening. The dough should be soft and very smooth.
3. Let the dough relax for about 30 min. cut pieces of dough weighing 100 g/450g.
4. Mould in along oblong shape and place in baking pans.
5. Proof the moulded dough to a desired height.
6. Bake at 210oC to a golden colour.
7. Cool the loaves overnight.
8. Cut the rusk of desired thickness. Arrange on baking sheets and toast at 190oC till these are crisp and golden brown in colour.
9. Cool and packaged.