Search results
Results from the WOW.Com Content Network
The subsurface field drainage systems consist of horizontal or slightly sloping channels made in the soil; they can be open ditches, trenches, filled with brushwood and a soil cap, filled with stones and a soil cap, buried pipe drains, tile drains, or mole drains, but they can also consist of a series of wells.
The primary method of controlling soil salinity is to permit 10–20% of the irrigation water to leach the soil, so that it will be drained and discharged through an appropriate drainage system. The salt concentration of the drainage water is normally 5 to 10 times higher than that of the irrigation water which meant that salt export will more ...
In addition, land drainage can help with soil salinity control. The soil's hydraulic conductivity plays an important role in drainage design. The development of agricultural drainage criteria [3] is required to give the designer and manager of the drainage system a target to achieve in terms of maintenance of an optimum depth of the water table.
Development analysis can add significantly to the value of land and development, and as such is a crucial tool for landowners and developers. It is an essential step in Kevin A. Lynch 's 1960 book The Image of the City , and is considered to be essential to realizing the value potential of land. [ 2 ]
In drainage research the collection and analysis of field data is important. [ 5 ] 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.
Vertical drainage systems are drainage systems using pumped wells, either open dug wells or tube wells. Map of a well field for subsurface drainage with radial flow across concentrical cylinders representing the equipotentials. Both systems serve the same purposes, namely water table control and soil salinity control.
SuDS efforts make urban drainage systems more compatible with components of the natural water cycle such as storm surge overflows, soil percolation, and bio-filtration. These efforts hope to mitigate the effect human development has had or may have on the natural water cycle, particularly surface runoff and water pollution trends. [6]
the development of new irrigation schemes became technically, financially and organizationally so complicated that they fell outside the capabilities of the smaller communities the import and export policies of governments required the cultivation of commercial cash crops whilst, by controlling the water management, the farmers could be more ...