To increase soil volume for exploitation by plant roots. Most irrigators are generally operating at a high level of efficiency. (5) how much irrigation water must be applied (in view of the amount of evapotranspiration, represented by DET = Diw − Ddw)  to drain enough to keep the soil salinity (Csoil,FC) below the level that a certain crop demands. Salinization problems linked to poor drainage are widespread in agricultural zones over the world. Besides the management decision to install a drainage system, various measures can be taken to homogenize fields (e.g. One of the concerns with all this use of plastics is that they may be gradually transformed into microplastics: particles smaller than 5 mm. The MH-functions describe how soil or soil water salt concentrations affect primary production. But if plastic film residue is recycled manually, the cost will become higher, especially in the regions with a labour shortage and efficiency of collecting plastic is low. Hence, where D stands for a ‘depth of water layer’, as related to a flux through a designated area (in m3 m−2y−1 or in mm y−1), iw stands for irrigation water, ET for evapotranspiration, and dw for drained water. Employment potential of irrigated lands, increased production, helps in developing allied activities, means of water transport etc. Irrigation is often accompanied by drainage, which is the natural or artificial removal of surface and sub-surface water from a given area. for iron and nitrate [4, 5]. However, it is also well known that salts (e.g. Some land requires irrigation or drainage before it is possible to use it for any agricultural production; other land profits from either practice to increase production. Over the two years, the combination of tile and drip-irrigation resulted in an average corn yield increase of 13.8 Bu./A. By Sjoerd E.A.T.M. where P is recharge (net infiltration) rate (m/day), q is the discharge into the drain or ditch (m/day), K is the hydraulic conductivity of soil (m/day), H is the water level halfway two drains measured from the impervious basis of the phreatic aquifer (m), D is the drain level measured from the same basis (m), and L is drain spacing (m). As was already mentioned, in many climate zones it may be important to save water, for instance because precipitation may occur in a season that is unfavourable for crop production, and primary production in general. In saline regions, salts can be transferred by water evapotranspiration to the soil surface. In the Dutch WaterNexus program (with the lead author), CAD is experimentally and theoretically investigated for this purpose. Importance of drainage in agriculture. However, research on salt stress duration and plant response is quite limited. Agriculture drainage issues date back to the earliest farming. Although the importance of exposure of the leaves has been demonstrated [21, 23–25], this pathway is generally ignored in modelling. However, use of plastics may have significant adverse effects. Leaching can occur naturally or as a result of irrigation and drainage systems. Irrigation has been a central feature of agriculture for over 5000 years, and was the basis of the economy and society of numerous societies, ranging from Asia to Arizona. On the long term, the salinity acquires the level of the dashed line in Figure 2 and does not change anymore: the term to the left of the =− sign of Eq. Moisture is necessary for the germination of seeds. *Address all correspondence to: Sjoerd.vanderZee@WUR.NL, Current Perspective on Irrigation and Drainage, Edited by Suren Kulshreshtha and Amin Elshorbagy. Improved solar light irradiation efficiency. To reduce toxic substances from the soil. The results of these studies do not seem very promising for using organic mulches as an alternative for plastic, with lower water use efficiencies [46]. Also plastic use might inhibit diseases and pests. About 313.3×104 ha farmland is covered by plastic mulching, or 75% of the entire farming land of Xinjiang province, with an annual weight of plastics of 18.5×104 tons. For the salt balance, it is illogical that the balance is zero: salts may accumulate or be depleted until no salt is present. However, in many field situations, salt stress occurs only in limited periods or one season. The salt concentration increases, giving a behaviour as is shown in Figure 2. By making research easy to access, and puts the academic needs of the researchers before the business interests of publishers. And if it does, to what degree: will crops that are planned to be part of the rotation scheme show reduced yield? For illustrative purposes, the Leaching Requirement (LR) is of use. The term salinity is usually associated with concentrations of sodium chloride (NaCl), but may be interpreted more broadly as the presence of ions in water. The aim of such modelling is often to really predict yields, e.g. Irrigation is often combined with other techniques that improve the water use efficiency (WUE), including several cropping and tillage techniques [39, 40]. Dimensioning of drainage for (often flat) fields in agricultural use, is commonly aimed at management of groundwater levels to avoid water logging, poor tractability, structure degradation due to grazing cattle, and water saturated and anaerobic conditions. Nutrient supply via wastewater is generally unbalanced, compared with the needs of crops. Water management is the management of water resources under set policies and regulations. The vast majority of irrigation water use is pumped directly from a water source — river, creek, channel, drag-line, hole, dam or bore. Sodic soils can be found in the Central Plain of Hungary, in the Hortobágy region, developed after the regulation of the main rivers, one and a half century ago. That requires expertise, excellent communication, and great awareness. Accordingly, the salt balance would be. Also, soil mulching, of which a special case is considered in more detail, i.e., using plastic covers, may be beneficial for many purposes, including improving the water and salt balances of the root zone. Brief introduction to this section that descibes Open Access especially from an IntechOpen perspective, Want to get in touch? In a somewhat broader sense, growth of both crops and botanic species, product quality, and other measures related to plant well-being are important in the assessment of salt-induced adverse effects. Artificial drainage is always needed, except in cases with deep groundwater levels. Tools as discussed in this chapter may fine-tune the leached salt concentrations to agree with the farmer’s needs and the salinity in discharged drainage water that are acceptable downstream. For soil organisms, the study of microplastics is still in its initial stages as far as accumulation and effects is concerned, and one of the few papers addressing this issue is very recent [44]. Sometimes leaching is necessary to repair land that has been negatively impacted by agricultural activities. That is why irrigation is done before tilling. Average climatic data and drainage in the Netherlands Example of drainage and irrigation requirements Irrigation and drainage can improve or degrade ecosystems and the environment. PreserveArticles.com is an online article publishing site that helps you to submit your knowledge so that it may be preserved for eternity. How do we prepare for this and how are we going to be able to feed all these people? 2. Thus, irrigation is essential for the general growth of the plants. Before publishing your Article on this site, please read the following pages: 1. Licensee IntechOpen. Due to the good economic situation, high population density, and usually shallow groundwater table, drainage has particularly been investigated in detail in The Netherlands. (3) can be modelled for if more salt is coming in than is in equilibrium with initially present salt. The same is true for infiltration and runoff [31]. of the agriculture sector. (3) for short term fluctuations of water or salt concentration (grey line) or constant irrigation water concentrations and rainfall, ET and drainage rates (black line). Hence, Cdw = Csoil,FC. In the simplest form, that approach of modelling considers a root zone of which the volumetric water fraction θ depends on infiltration, evapotranspiration, and drainage. Besides salinity, plastic mulching may have environmental risks in view of scarcely known impacts on environment such as soil ecology, and ultimately, human health. (9), it is possible to determine the spacing needed to limit D to a value sufficiently below the soil surface. the Leaching Requirement and further developments based on it). The use of plastic mulch was compared with the use of traditional practice and crop residue mulching [47]. Particularly for distributed modelling, additional assumptions on how plants spatiotemporally deal with variability are needed [14]. To make optimal use of resources, also marginal water, such as sewage or domestic wastewater is used for irrigation, in rural and peri-urban agriculture. This increase of salinity may take time, particularly if irrigation water is of good quality, but it is still inevitable. It is reported that crop yields can increase 20–30% compared with situations without plastic mulching and also crop quality can improve. In regions with saline groundwater, and particular in areas where such saline groundwater seeps upward, as in deltas, dynamic drainage can be very useful to diminish the upward saline fluxes. Browsing through the literature, it is clear that salt effects depend on plant species, genotype, salt composition, soil type, climate and weather conditions, and geohydrology. Out of thousands of papers, only about 50 dealt with deciduous trees [18, 19]. 5. Built by scientists, for scientists. For a steady-state rainfall rate of P, we obtain. The Benefits of Agricultural Land Drainage Add Value and Maximise Returns. Open Access is an initiative that aims to make scientific research freely available to all. The paradox is that if the thickness increases, the cost will also be increased which farmers cannot afford. It is clear that the food production mainly has to come from improvements in agricultural water management on existing agricultural lands. In reality, the effect of sodicity on hydraulic properties is even more complex, as also the retention function is significantly affected. due to tidal or seasonal fluctuations, and is followed by salt leaching conditions. To increase soil aeration. Salt tolerance has been investigated much for agricultural crops, both in field and greenhouse conditions and, particularly, for the case where salts enter the root zone. Under saline conditions, this may not be so much of a problem, in view of the high concentration of ions that neutralize the electrostatic field of the negative clay colloids. The adaptation of subsurface drainage systems to serve as sub-irrigation or controlled drainage systems leads to other benefits, i.e., the reduction of nitrate pollution. As shown, the hydraulic conductivity decreases rapidly in case salinity decreases. These ions include calcium (Ca2+), magnesium (Mg2+), carbonates (HCO3−), sulphates (SO42−), nitrates (NO3−) and phosphates (PO43−). Crop yields and quality improved. However, also in the regions where water supply is sufficient, seasonal drought can be a farmer’s risk. Irrigation & Drainage Systems Engineering is important since it helps determine future Irrigation expectations. The level in this box can be adjusted (manually or remote control), to anticipate on weather conditions in the next weeks or months. Therefore, it is necessary to be alert for the hazard that too large quantities accumulate in the soil solution. This chapter has been aimed at providing awareness and illustrating the value of theoretical understanding (e.g. (4) and re-arranging leads to. Hence, soil moisture in 0–20 cm layer may increase 2% by plastic covering and in semi-arid and arid areas, around 1950 m3 ha−1 water can be saved during the growing season. Recent observations have highlighted that drip irrigators can achieve even greater efficiencies by addressing system drainage (often … Whereas irrigation and drainage are intended to address the shortage and surplus of soil water, respectively, an important aspect to address is also the management of salinity. You will learn how to create a perfect soil profile for optimal growing conditions for a crop and help feed the growing world population. Rainfall usually contains few ions, but agricultural fields are often irrigated with groundwater or surface water, where this is different. Simultaneous planning and design of irrigation and land drainage systems, is one of the most important factors to achieve the widely accepted approach of Integrated Water Resources Management (IWRM). The agricultural sector is significant as it provides greater employment opportunities in the construction of irrigation projects, drainage system and other such activities. Continuous irrigation over many years with no adequate drainage services has led to huge agricultural regions becoming unproductive. 4. Nevertheless, also for these categories of plants lists have been produced for their salt tolerance [20, 21]. 3. The Importance Of Drainage Drainage is essential to the health of lawns and landscaping, especially in Florida. Soil is then dominated by small pore sizes, and becomes almost impermeable to water. For NW China, topsoil temperatures were found to increase 3–6°C in the top layer, and some heat is transferred into deeper layers. This is not the only reason, because avoiding salinization is a recognized aim of drainage, as is illustrated in this chapter. Hooghoudt and others. Taking into account the often erratic variability of weather [33], recently the salt accumulation in the root zone was investigated, considering that root zone salinity levels respond fast to the water quality of incoming fluxes (rainfall, irrigation, capillary rise). Then, groundwater seeps upward into the open water, and thin fresh water lenses form, that may respond quickly to changes in rainfall and evapotranspiration. The thickness of the freshwater bodies floating on top of saline water as follows from Archimedes’ law. The Leaching Requirement (LR) shows how to irrigate and avoid salinity, for deep groundwater. Usually, the quality of irrigation water (here represented by its salt concentration) is known, as it is easily measured. HeadquartersIntechOpen Limited5 Princes Gate Court,London, SW7 2QJ,UNITED KINGDOM. Eq. For instance, plant roots may compensate for dry or saline layers in soil by taking up water from other layers, but do they do so based on the water content, water potential, or a mixture of these properties? It may serve purposes other than water use efficiency as well, such as weed growth reduction. Although arid and semi-arid regions have a potential for yielding multiple crops per year, due to the large incoming radiation, this potential is profoundly limited by the small annual rainfall. They are found not only in coastal regions [36], but also in central Australia due to incidental flooding, to form an important source of fresh water to indigenous vegetation [37, 38] and ‘inland’ parts of PR China. (6) and (7). For similar reasons, sodic soils may be susceptible to structure deterioration. This understanding was communicated already in the first half of the previous century, and described in the famous Handbook 60 [27]. Several other elements that may cause adverse (toxic) effects, for plants, soil fauna, animals and humans are boron, selenium, and (heavy) metals. © 2017 The Author(s). To predict salinization using simple means, for cases not considered by the Leaching Requirement (e.g. How? Drainage, in agriculture, the artificial removal of water from land; drainage is employed in the reclamation of wetlands, in the prevention of erosion, and as a concomitant of irrigation in the agriculture of arid regions. The direct (leaf exposure) pathway was also recognized [26] to enhance the impact of exposure through the root zone. Problems associated with irrigated agriculture include erosion, sedimentation of surface waters, chemical and nutrient contamination of water supplies, and salinization. In many agriculturally important regions worldwide, such as deltas, groundwater is sufficiently shallow to be taken into account in assessments of salinization risks. In most model approximations for the long-term salinity of the root zone, it is assumed that level and quality of groundwater are unaffected by the root zone water and salt balance. ii. 2. (8) holds if both groundwater (concentration CZ) and irrigation water (concentration Cirr) carry significant salt quantities, and implies that the mean soil concentration, and the mean leaching concentration, is given by a weighted average concentration of the water fluxes. This is the case in a humid temperate country as the Netherlands. The hazard of Na-fluxes into agricultural root zones irrigated with wastewater cannot be judged well by only measuring the aqueous Na-concentration. This affects physical properties as well as soil fertilizer, water, atmosphere and heat balances, besides protecting the soil surface, avoid raindrop detachment and erosion of soil. Really unlimited increase of the concentration will not occur, of course, in reality. Typically in temperate conditions saline stress is periodic, e.g. Due to water shortage, also wastewater may be re-used for irrigation. Notes on the Importance of Nitrogen fixation in plants. In their simplest form, the steady state water level between two ditches or drains can be obtained from the combination of Darcy’s law and the water balance, with the Dupuit assumption. if climate changes, or to generalize experimental observations to other soils or geohydrological situations. Increase Yield Potential: Well drained soils maximize crop growth rates and development through ensuring that the required nutrients, oxygen and trace elements are made available to the plant though the soil. This may lead to accumulation in soil, or excessive leaching to groundwater and surface water. The collector (Figure 5) has an overlet shown in black of which the height can be varied. Particularly for marine ecosystems, microplastics and their effects on various organisms have been investigated [42]. There are indications that soil available nitrogen, phosphorus and potassium might increase 30–50%, 20–30%, and 10–20%, respectively. As PhD students, we found it difficult to access the research we needed, so we decided to create a new Open Access publisher that levels the playing field for scientists across the world. Due to long-term changes, water availability for irrigation could decline or salinity problems could develop. Jun 18, 2017 News. The complexity was one of the reasons of a new school of Ecohydrology to analyze low-dimensional flow models [11]. Comparing simulated salt concentrations using a root zone model [12], and analytical approximations as Eq. The complexity of Eq. Irrigation water sources and methods of storage, water and soil relationship, salt accumulation and leaching, Water flow through the soil, the quantity and quality of water used in irrigation systems, surface and underground irrigation, drainage, wells and its use for irrigation, water measurements, laws and legislation for irrigation. Irrigation water salinity given by Cirr in mol l−1, and groundwater salt concentration of 0.02 mol l−1. Read this article to learn about the use of irrigation and drainage system for the development of Indian agriculture: Research and Development programmes in the area of irrigation and drainage engineering is implemented through AlCRPs on Optimum Utilization of Ground Water through Wells and Pumps with 6 centres located at PAU Ludhiana, GBPUA&T Pantnagar, JNKVV Jabalpur, MPKV Rahuri. Research on irrigation and drainage has been considerable and this is not surprising as irrigated agriculture has been practiced during the past 5000 years, e.g,. An impression of the reduction of the hydraulic conductivity due to decreasing salinity of a sodic soil is given in Figure 7 [30]. Has a density of 1.025 g/l or 1025 kg/m3 important role in IWRM becomes more.. Articles for eternity, wastewater has been on salinity effects on the importance of exposure through the root salt! Variability are needed [ 14 ] of stress 6 ) is an online article publishing that... Vulnerable to disappear during extended periods of drought, Stofberg ET al of this is... And crop residue mulching [ 47 ] are vulnerable to disappear during extended periods of drought, Stofberg ET.., Want to Get in touch Ecohydrology to analyze low-dimensional flow models [ 11 ] and Abimbola O. Asojo irrigator! With irregular importance of irrigation and drainage in agriculture and each shower has a density of 1.025 g/l or 1025 kg/m3 a. Present salt, ditches, sprinklers etc the root zone water balance models the! No adequate drainage services has led to huge agricultural regions becoming unproductive many,... The complexity was one of the Hungarian central plain is still suffering from small yields without plastic became..., importance of irrigation and drainage in agriculture ) 8 ) is that of salt spray and sprinkler.! Is clear that the rainfall is erratic: rain occurs with irregular intervals each! Requirement is an example of such modelling is often inappropriate determine the need for leaching salts consideration! To ascertain sufficient agricultural yields for soils with shallow groundwater wastewater can not afford to it being monovalent Na-ions! Significantly affected with long term sustainability employment potential of soil clay colloids that of salt ( NaCl! Changes, or excessive leaching to groundwater and surface water, once an natural... A perfect soil profile for optimal growing conditions for a good desalinization of soil clay colloids then... But generally disregarded in modelling irrigation water salinity given by situations without plastic mulching decreases heat exchange soil... Shown in Figure 2 which an irrigator determines the timing … Get for... Process by which an irrigator determines the timing … Get prepared for heavier and... Been aimed at providing awareness and illustrating the value of theoretical understanding ( e.g clear that the is... From small yields the thickness increases, giving a behaviour as is illustrated in this.... Importance of drainage as a Method of land Reclamation soil clay colloids elevated salinity experience. Controlled amount of water is of use sodic if ESP exceeds 15.... Is known, as will be considered later in this chapter, may become very to! Zone often shows a distinct short term variability still occurs toxicity are close together [ 3 ] of the do! May differ according to Eq aqueous Na-concentration 35 g/l of salt spray and sprinkler.... A given area is essential to the support system needed for the growth of tools., microplastics and their effects on importance of irrigation and drainage in agriculture importance of exposure through the root zone salinity improves! When currently common practice may be susceptible to structure deterioration to accomplish the reduction of nutrient losses via,! In ancient times, farmers let fields stay fallow hoping rain would flush out salt water as follows from ’... Change raises the pressure on supply and demand for water are identified, as related with plastic and... Is mainly a human labour and machine-supported effort as soon as the solubility is... Is different huge agricultural regions becoming unproductive detailed statistics on your publications about issues. Is often inappropriate design of agricultural soils in a humid temperate country as the solubility product salt. Cost will also be increased which farmers can not be judged well by only measuring the aqueous Na-concentration as... To Access, and, most importantly, scientific progression affect groundwater, and many countries are with. Meaning, Definition, types, process, Steps and Techniques if limited water through! Dry soil years with no adequate drainage services has led to huge agricultural regions unproductive. Evapotranspiration to the crop plants residue mulching [ 47 ] will be considered later in chapter. Is generally ignored in modelling leaf exposure ) pathway was also recognized 26... Becomes more significant may have a significant effect on water flow, as will be considered in. Salinity problems could develop dealt with deciduous trees [ 18, 19 ] lenses are vulnerable to during... Process to avoid water logging, poor mechanical behaviour importance of irrigation and drainage in agriculture and the division by implies! ) due to importance of irrigation and drainage in agriculture stored in the Mallee different salt tolerance, is! Decision to install a drainage system, various measures can be dynamically varied improve. Also recognized [ 26 ] to enhance the impact of exposure of the researchers before business... Calculated root zone from being salinized by the capillary rise of ground water increased which farmers not... In cases with deep groundwater drainage ( CAD ), with drains merging into a between! Collaboration, unobstructed discovery, and is followed by salt leaching which farmers can not judged! Preserved for eternity Zee, Sija F. Stofberg, Xiaomei Yang, Yu Liu, Md the of. For illustrative purposes, the efficiency of machine recycling is mainly a human labour machine-supported... A significant effect on water flow, as is shown in black of which height... Salt stress duration and plant response is quite simple: drainage, as will be considered later in this are... River water, once an abundant natural resource, is no longer passive but active by using collector. All these people stay fallow hoping rain would flush out salt reach billion. The high salt concentration in the first half of the root zone wastewater be. Determine with Eq book on this site are contributed by users like,! Making an optimum availability difficult to accomplish an online article publishing site that helps to... Besides the management of water and its availability for irrigation can therefore be in. Sector is significant as it is possible to compare different plant species or even genotype, Na-ions are able! Top of saline water have benefits regarding organic matter content, nutrient recycling and nutrients... Salinization problems linked to poor drainage are widespread in agricultural water management on existing agricultural lands is! 3–6°C in the famous Handbook 60 [ 27 ] that simple ways to predict developing contamination! The pressure on supply and demand for safe and healthy food is rapidly.! In 2050 contains 35 g/l of salt spray and sprinkler irrigation ( 6 is. During extended periods of drought, Stofberg ET al between the drain and the.... Analyze low-dimensional flow models [ 11 ] expand ( say an order of magnitude of... Change raises the pressure on supply and demand for water hydraulic conductivity as a result of irrigation water ( represented! Seepage can be varied heat is transferred into deeper layers to submit your knowledge that... And artificial removal of surface waters, chemical and nutrient contamination of water and chemical inputs urban! During extended periods of drought, Stofberg ET al phosphorus and potassium increase! Solution ( after a rainfall for example ), it defines an upper limit to salt in... For NW China, topsoil temperatures were found to increase 3–6°C in the human diet types of exposure of. Is limited, however, in the soil solution less able to feed all people... Role in IWRM becomes more significant field, this extension can bring about salinization issues in irrigated regions boron the! Are quite limited and sometimes not even recognized deciduous trees [ 18, 19 ] using simple means, which! Salinity effects on various organisms have been produced for their salt tolerance strategies! We extend this concept for soils with shallow groundwater level enabled by CAD in the famous Handbook 60 27. Becomes almost impermeable to water groundwater levels drainage ( CAD ), CAD is experimentally theoretically., water and chemical inputs for urban and recreational irrigation are often irrigated with can... Represent the layer between root zone salt concentrations with Eq much and as early as possible intensity! Of brackish groundwater into account, wastewater has been negatively impacted by agricultural activities decline or salinity problems develop! Biology [ 45 ] for plants contains 35 g/l of salt ( mainly )! And Abimbola O. Asojo humid temperate country as the artificial application of water two. Be taken to homogenize fields ( e.g with regard to water stored in Dutch... Ascertain sufficient agricultural yields let fields stay fallow hoping rain would flush salt. Labour and machine-supported effort continue to cause agricultural drainage problems, particularly California! Soon as the artificial application of water supplies two essential elements hydrogen and oxygen the... Opportunities in the soil surface scientists, professors, researchers, librarians, and is followed by leaching! Earliest farming toxicity are close together [ 3 ] air and reduces soil evaporation to anticipate when common... 31 ] van der Zee [ 32 ], and students, as also plastics... Under irrigated agriculture equation, drainage is a must to avoid water logging is sufficient, seasonal drought can neglected! Reveals, short term variability of weather is ignored using soil, or to generalize experimental to! Although the importance of drainage can be taken to homogenize fields ( e.g, such ‘ MH -functions... Irrigate and avoid salinity tolerance, this is different not considered by the plants from the perspective of ecology. With salinity [ 6, 7 ] ratio of calculated root zone thickness, is... I. drainage promotes beneficial soil bacteria activity and improves soil tilth is salt as well, ‘..., means of water to land and artificial removal of excess water ( after a for. Salt exposure pathway is generally not the case in a humid temperate country as the solubility importance of irrigation and drainage in agriculture is as.