- Drainage research
Drainage research is the study of agricultural drainage systems and their effects to arrive at optimal system design.
Aspects to be covered
Agricultural land drainage has agricultural, environmental, hydrological, engineering, economical, social and socio-political aspects (Figure 1).
All these aspects can be subject of drainage research.
The aim (objective, target) of agricultural land drainage is the optimized agricultural production related to:
- reclamation of agricultural land
- conservation of agricultural land
- optimization of crop yield
- crop diversification
- cropping intensification
- optimization of farm operations.
The role of targets, criterion, environmental, and hydrological factors is illustrated in Figure 2.
In this figure criterion factors are factors influenced by drainage on the one hand and the agricultural performance on the other.
An example of a criterion factor is the depth of the water table:
- A drainage system influences this depth; the relation between drainage system design and depth of water table is mainly physical and can be described by drainage equations, in which the drainage requirements are to be found from a water balance.
- The depth of the water table as a criterion factor needs to be translated into a criterion index to be given a numerical value that represents the behavior of the water table on the one hand and that can be related to the target (e.g. crop production) on the other hand.
- The relation between criterion index and target can often be optimized, the maximum value providing the ultimate aim while the corresponding value of the criterion index can be used as an agricultural drainage criterion in the design procedure.
Crop response processes
The underlying processes in the optimization (as in the insert of Figure 2) are manifold. The processes can be grouped into mutually dependent soil physical, soil chemical/biological, and hydrological processes (Figure 3):
- The soil physical processes include soil aeration, soil structure, soil stability, and soil temperature
- The chemical processes include soil salinity, soil acidity and soil alkalinity.
- The hydrological processes include evaporation, runoff, and soil salinity.
Examples of processes can be found in.
In drainage research the collection and analysis of field data is important.
In dealing with field data one must expect considerable random variation owing to the large number of natural processes involved and the large variability of plant and soil properties and hydrological conditions.
An example of a relation between crop yield and depth of water table subject to random natural variation is shown in the attached graph. The graph was made with the SegReg program, see segmented regression.
Soil salinity control
In irrigated lands, subsurface drainage may be required to leach the salts brought into the soil with the irrigation water to prevent soil salination.
Agricultural water management IrrigationSurface irrigation · Tidal irrigation · Irrigation of alluvial fans · Irrigation statistics · Irrigation management · Irrigation environmental impacts Subsurface drainage Surface water/runoff Groundwater Problem soils Agro-hydro-salinity group Related topicsSand dam ·
- ^ Drainage for Agriculture: Hydrology and Water Balances. Lecture notes, International Course on Land Drainage (ICLD), International Institute for Land Reclamation and Improvement (ILRI), Wageningen, The Netherlands. Download at : 
- ^ Agricultural Drainage Criteria. Chapter 17 in: H.P.Ritzema (ed., 1994), Drainage Principles and Applications, Publication 16, p.635-690. International Institute for Land Reclamation and Improvement (ILRI), Wageningen, The Netherlands. ISBN 90 70754 3 39. Download at : 
- ^ Drainage Research in Farmers' Fields: Analysis of Data. Part of project “Liquid Gold” of the International Institute for Land Reclamation and Improvement (ILRI), Wageningen, The Netherlands. Download at : 
- ^ SaltMod: A tool for interweaving of irrigation and drainage for salinity control. In: W.B.Snellen (ed., 1997), Towards integration of irrigation, and drainage management. Special report, p. 41-43, International Institute for Land Reclamation and Improvement (ILRI), Wageningen, The Netherlands. Download at : 
Wikimedia Foundation. 2010.
Look at other dictionaries:
Drainage equation — A drainage equation is an equation describing the relation between depth and spacing of parallel subsurface drains, depth of the watertable, depth and hydraulic conductivity of the soils. It is used in drainage design. Parameters in Hooghoudt s… … Wikipedia
Drainage system (Agriculture) — An agricultural drainage system is a system by which the water level on or in the soil is controlled to enhance agricultural crop production.=Classification=Figure 1 classifies the various types of drainage systems. It shows the field (or… … Wikipedia
Drainage system (agriculture) — An agricultural drainage system is a system by which the water level on or in the soil is controlled to enhance agricultural crop production. Contents 1 Classification 1.1 Surface drainage systems 1.2 Subsurface drainage systems … Wikipedia
Drainage — See also: Storm drain and Stormwater Deep inside a Sydney drain in New South Wales Drainage is the natural or artificial removal of surface and sub surface water from an area. Many agricultural soils need drainage to improv … Wikipedia
Research and development in Ohio — Ohio is a major research and development center, home to many institutions. Contents 1 Overview 1.1 Government and non profit 1.2 Private 1.3 Collegiate … Wikipedia
Drainage law — is a specific area of water law related to drainage of surface water on real property. It is of great importance in areas where freshwater is scarce, where flooding is common, or where water is in high demand for agricultural or commercial… … Wikipedia
Well drainage — means drainage of agricultural lands by wells. Agricultural land is drained by pumped wells (vertical drainage) to improve the soils by controlling water table levels and soil salinity. Contents 1 Introduction 2 Design 3 Flow to wells 4 … Wikipedia
Tile drainage — (in agriculture) is an agriculture practice that removes excess water from soil subsurface. Whereas irrigation is the practice of adding additional water when the soil is naturally too dry, drainage brings soil moisture levels down for optimal… … Wikipedia
Internal drainage board — An internal drainage board (IDB) is a type of operating authority which is established in areas of special drainage need in England and Wales with permissive powers to undertake work to secure clean water drainage and water level management… … Wikipedia
Acid mine drainage — Yellow boy in a stream receiving acid drainage from surface coal mining. Acid mine drainage (AMD), or acid rock drainage (ARD), refers to the outflow of acidic water from (usually abandoned) metal mines or coal mines. However, other areas where… … Wikipedia