eChapters

26.1. What?

These devices are used to lift water to a height that allows access to water. Lifting devices can be used to lift groundwater, rainwater stored in an underground reservoir and river water. For agricultural use, water is lifted either from a borewell or open well to irrigate the crops. According to power sources, lifting of water can be accomplished either manually or by animal or electricity sources of power.

26.2. Human-powered devices

Man has a limited physical power output, which may be in the range of 0.08 to 0.1 hp. This power can be used to lift water from shallow depths for irrigation. These include swing basket, counterpoise lift, don, Archimedean screw and paddle wheel. However, nowadays these are not commonly used.

26.3. Animal-powered devices

Animal power is abundantly available in India. They are used to lift water, besides being put to use for other field operations and processing works. A pair of bullocks may develop approximately 0.80 horsepower. They can lift water from a depth of 30m or more. Of course, the rate of discharge will go down with increase in the lift. These include rope and bucket lift, self emptying bucket, two bucket lift, Persian wheel and chain pump.

Abstract: Water lily, bulbous ornamental, constitute element of aquatic gardens. A variety of flower colour, flower forms, modes of reproduction and leaf sizes exist in Nymphaea. This species is a complex hybrid group. A wide range of polyploidy (including aneuploidy, trisomy, polysomaty), polymorphism and heterozygosity exists within the cultivars of water lily. Genetic information and trait heritability is almost unknown for this crop. Breeders have created synthetic water lily hybrids. Low fecundity, limited fertility, reproductive barriers, low seed set, relatively low elemental (founding) species among elite germplasm often pose significant challenges to flower breeders. Breeding objectives with high priority include tolerance to drought, year round flowering and lower seed tannins. Future breeding and genetic studies are needed to further transform this crop.

Keywords: Nymphaea, correlation, sterility, interspecific hybridization polyploidy.

Water lily is an important aquatic ornamental flower crop valued for its attractive flowers, cultural significance and use in water gardens, ponds and decorative landscapes. Different flower colours and forms provide considerable ornamental diversity, while flowers also have importance in religious and ceremonial activities. The chapter introduces water lily through its botanical characteristics, origin, distribution, genetics and important varieties. It discusses the environmental conditions required for successful cultivation, including suitable water bodies, soil and temperature conditions. Propagation, planting, nutrient management, irrigation and routine cultural operations are described. The chapter also covers pest and disease management, flower harvesting, postharvest handling, yield and commercial possibilities associated with water-lily production.

Submerged soils/Flooded soil

Submerged soils are the type of soils that are saturated with water for a sufficiently long time in a year. This gives the soil the following distinctive gley horizons resulting from oxidation-reduction processes:

The soil is intermittently saturated with water, oxidation of organic matter is slow and it accumulated within the “A” horizon. Fe and Mn are deposited as rusty mottles or streaks if the diffusion of O2 into the soil is slow in the second horizon, whereas if the diffusion is rapid, they are deposited as concretions.

Types of submerged soils

1. Waterlogged soils- Waterlogged soils are saturated with water for a sufficiently long time annually to give the soil the distinctive gley horizons resulting from oxidation-reduction processes. Saturation with water may be due to impermeability of the soil material, or the presence of an impervious layer, or a high water table.

2. Marsh Soils- These types of soils are more or less permanently saturated or submerged. Freshwater marshes can be classified according to their origin into upland, lowland, and transitional. Upland marshes are poor in bases and have pH 3.5-4.5 because they receive mainly rainwater. Lowland marshes are saturated or submerged with water-carrying bases and have pH 5.0-6.0.

16.1 Water logging

For optimum growth and yield of field crops, proper balance between soil air and soil moisture is quite essential. Except rice many of the cultivated plants cannot withstand excess water in the soil. The ideal condition is that moisture and air occupy the pore spaces in equal proportions. When the soil contains excess water than that can be accommodated in the pore spaces it is said the field is water logged.

Causes of water logging

1. Excessive use of water when the water is available in abundance or cheaply due to the belief that more water contributes better yield.

2. Improper selection of irrigation methods

3. Percolation and seepage from lands canals and reservoir located at nearby elevated places

4. Improper lay out and lack of outlets

5. Presence of impervious layer with profile impeding percolation

6. Upward rise of water from shallow ground water table or aquifer.

Water Scarcity Issues
The world is running out of clean water. The subsurface water table decreases and surface runoff rises as a result of deforestation. The amount of water stored underground is decreasing as wells are being dug deeper and deeper. As a result of desertification and deforestation, perennial rivers are turning seasonal. There is not enough potable drinking water because of abuse and overuse.
Conserving Water
• In certain situations, manipulating plants, harvesting water, and other techniques might increase the availability of water supplies.
• Water use reduction achieved by the application of water efficiency or conservation techniques; alternatively,
• Better techniques for managing water can either decrease or increase the useful use of water.
• Any activity, behavioral modification, tool, technology, or better design or procedure used to lower water loss, waste, or use is referred to as a water conservation method.
• One method of conserving water is water efficiency.
Among the Objectives of Water Conservation Initiatives
• The goal of sustainability is to guarantee that water extracted from an ecosystem will not be lost faster than it naturally replaces itself for future generations.
• The pumping, delivering, and treating of water results in energy conservation.
• Habitat conservation includes limiting the amount of water used by humans, which lessens the need to construct new dams and other water diversion infrastructure while also preserving freshwater habitats for nearby species and migratory waterflow.

Soil, climate and water decide the nature of crop to be grown in a particular region. While soil and climate can be manipulated to certain extent, there is no substitute of water. Water is governed by the hydrological cycle. The major source of water is rainfall which has been reduced over the years due to climate change. The per capita water availability in India was 4944 m3 in 1955 which has been reduced to 1750 m³ now and is expected to come down to 1500 m³ by 2025.

Introduction

The climatic elements such as solar radiation, temperature, precipitation, humidity, evaporation, evapotranspiration and wind velocity affect growth and development of saplings. These climatic factors are not favourable for successful propagation of various horticultural crops in arid region. The main climatic features of Indian hot arid agro-ecosystem is high wind speed, sand storm and high temperature during summers up to 48-50oC  and during winter season temperature falls to the 2-3^°C, low atmospheric humidity i.e. 20-30% during maximum period of the year. Moreover the relative humidity goes down to below 10 per cent during summer months.

Abstract

In the emerging era of wide spread use of IT tools, up-to-date information on water resources is the key to support economic development, conserve the nature as well as to improve the quality of life. Due to rapid rise in population  and food demand, growing economy and improving living standards; the pressure on our water resources is increasing and it will become scarce in the coming decades if not managed at this stage in a integrated way. Water resources management requires a multi-disciplinary approach that combines a collection of technical tools and expertise along with stakeholders of diverse interests and priorities in planning and management and an operational water resources information system at national level is the first requirement.

When rocks and minerals under go weathering process large quantities of soluble salts are formed. In humid regions these salts are washed down to the ground water and to the sea. But in arid and semi arid regions they accumulate in the soil. Excessive irrigation and poor water management are the two chief causes of water logging and salt accumulation. An accumulation of salts in soil leads to unfavourable soil water-air relationship and effect the crop production.

The following are the main causes which leads to development of salty soils (salinity or alkalinity)

Increasing population, declining natural resources, changing climate and political stability are the major threat to our food, nutritional as well as environmental security. It is expected that India’s population will boom to 1.5 billion by 2030 and to feed them we need approximately 341mt food grain including 315 mt cereals and 26mt pulses) (Kumar et al., 2016).

Water is a critical input for agricultural production and plays an important role in sustainable agriculture and food security. Agriculture is the principal user of water, accounting for around 70% of total withdrawals. Producing each calorie of food requires approximately one litre of water.

The coastal agro ecosystem is very important among the different agro ecosystems of our country both economically and environmentally. It spans over a length of 8129 sq. km. covering 9 states and 2 Island ecosystems. Agriculture and allied activities constitute the single largest component of India’s economy, contributing nearly 27 per cent of the total Gross Domestic Product (GDP) in the year 1999-2000 (TERI, 2002). Agriculture exports accounts for 13 to 18 per cent of total annual exports of the country (MoF, 2002). However, given that 62 per cent of the cropped area is still dependent on rainfall (MoEF, 2002). Coastal agricultural region comprises of hinterland, which has a varied geometric and topographical features of mountains valley, coastal plains, riverine systems, climatic conditions, different soils and water bodies, vegetation ranging from rich tropical rain forests to coastal mangroves and a wide range of crops that are cultivated in this region (Table 1). The agro climatic conditions of the coastal zones are congenial for growing various field and horticultural crops.

Relationship Between Plant and Water

Water is the most vital component of the living cells and the basis of plant feeding. Water is also characterized with extraordinary physical properties: it has high specific heat, biggest latent heat of vaporization, very high thermal conductivity and greatest surface tension. Large amounts of heat are tied up with water because of very high specific heat, which contribute to both climatic stability and to heat budgets of the plants and other organisms. Water molecules are integral part of living systems being the solvent for metabolites and structural component of proteins and nucleic acids. In fact, biological macro-molecules cannot exist in their complicated secondary folding or spiralled helixes without the support of hydrogen bonding within their water matrix. The water matrix is also critical for metabolic activity because its properties of hydration permit ready reactivity between molecules in solution as well as between enzymes and their substrates, and the biochemical processes are sensitive to tissue hydration. A reduction of only 20-25 per cent below maximum hydration is sufficient to cause metabolic malfunctioning of many enzymes. It is the substrate for photosynthesis and a product of respiration. Water also helps to buffer plant tissue against fluctuations in the external environment. Plant growth including leaf expansion, organ enlargement, reproductive development and stomata function are all clearly associated with moisture status. Hormonal changes (abscisic acid and cytokinins) in plant body occur with brief reduction in water potential. Water is the also major force in shaping the climatic patterns.

Water management in agriculture is a critical component of ensuring sustainable food production and environmental conservation. This article explores various strategies for conserving water in agricultural practices, examining both traditional methods and modern technological innovations. It addresses the challenges posed by climate change, population growth, and resource scarcity, highlighting the importance of efficient water use. Key strategies discussed include irrigation optimization, soil moisture management, rainwater harvesting, and the adoption of drought-resistant crops. The article also considers policy measures and community-based approaches that support water conservation. By implementing these strategies, the agricultural sector can contribute to sustainable water management and enhance food security.

Introduction

Indian agriculture was contributing 70% to total GDP of the country at pre-independent time, but it decreased drastically year by year and contributed 66.8% in 1960, 55.6% in 1994, 27.1% in 1997 and now a days, it reached only to 25% in 2001. With the advancement of civilization our population is increased, whereas, the cultivable lands is decreased side by side, thus, on an average income of agriculture is decreased.

Gujarat is the leading state to concern with the productivity, production and the area of the some crops like Groundnut, Castor, Cotton, etc. in India. The major part of the state is surrounded by sea coast border, which is 1600 km. Gujarat is popular for production of oilseed crops like groundnut, cotton ; horticultural crops like mango, chiku, coconut, banana, papaya, citrus; spices crops like chili, cumin, funnel etc.

1.0 Introduction

Population in dry lands of the world is increasing; more fresh water is required in order to meet the growing demands. To meet this challenging situation developing new technologies for identification of potential sites for rainwater harvesting (RWH) is an important step towards maximizing water availability in semi-arid areas.

Water is a critical input for crop production. Its optimum availability is important in augmenting and sustaining crop productivity. Lack of adequate supply of water can limit crop yields ranging from 10 to 90% or even be subjected to mortality if moisture go below permanent wilting point. It is also observed that the moisture shortage during some critical crop growth stages would cause severe detrimental effect. This necessitates us to provide irrigation to crops at right quantity and frequency. In other words, irrigation schedule plays key role in optimizing or maximizing crop yield. Moreover, judicious use of irrigation water has potential to enhance the agricultural productivity which in turn would lead to food security. As water resources are getting diminished day by day, the application of water saving techniques would be needed for addressing the food security objectives of the nation.

Irrigation is one facet of the inputs which need to be carefully managed so that profits are maximized. Irrigation plays a major role in any agriculture crop production. One should be aware of different types of irrigation adapted in orchards or crop cultivation to become a successful grower. Irrigation is very important component of crop cultivation as sufficient moisture must be maintained in the soil for obtaining the optimum growth and good quality yield. The aim of irrigating a plant should be to wet the entire root zone without allowing any wastage of water beyond the root zone. The irrigation systems have to be properly devised so that the water requirements of the trees are met at the minimum expenditure without any wastage of water. Irrigation practices can be improved if a range of important factors like crop type, crop water requirements, climatic conditions, soil type, water quality, method of irrigation are taken into account.

Crop type

The type of horticultural crops grown influences irrigation practices. Annual vegetable and melon crops have high water requirement, hence irrigation management is extremely critical to their productivity during their relatively short life span (10-20 weeks). Perennial fruit crops tend to require less water and management, although critical, is not generally as critical as for annual crops.

Pulses can be grouped into kharif and rabi pulses according to their temperature requirements. In India chick pea, pea, lentil and beans require relatively less temperature and are grown in rabi season, whereas others are confined to kharif season. However, kharif pulses can also be grown in pre-rabi on stored soil moisture or as irrigated crops in rabi and summer seasons.

Pulse crops have long tap root system which extracts soil moisture from deeper layers. Water uptake across the depth of rooting zone is not uniform. In general 40 per cent of the total water uptake occurs from first one fourth of the rooting zone, 30 per cent from the second, 20 per cent from the third and remaining 10 per cent from the last one-fourth region of total rooting depth (Nageshwararao and Writ, 1994). Plants often maintain higher root length densities than required in the surface layers to facilitate rapid uptake of recent rain/irrigation before it evaporates.