Examining wetting patterns and water distribution in drip irrigated substrate culture using thermography | |
| Author | Saleem, Amir |
| Call Number | AIT Thesis no.Wm-18-26 |
| Subject(s) | Wetting Microirrigation Water--Distribution |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Water Engineering and Management |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. Wm-18-26 |
| Abstract | Increasing utilization of available land for physical and infrastructural development rapidly decline the quality topsoil and thus promoting the utilization of soilless materials in the production of horticulture crops, a good growing media would provide desire anchorage, serves as reservoir for nutrients and water, allow oxygen diffusion to the roots and permit gaseous exchange between roots and atmosphere outside the root substrate. Studies relating to the determination of moisture profile have been conducted in the past but in these studies, different kinds of probes were used to investigate the moisture profile, presence of probes inside the media during observation could result cavitation causing unreliable measurement. The horizontal and vertical infiltration and water distribution in coco peat and incorporated coco peat with rice hull growth media was analyzed under varying conditions of drip irrigation in term of emitter rate, irrigation volume and initial moisture content and effect of packing denities of coco peat and rice - coco media on its wetting characteristics were examined using thermography. Emitter flow rates 0.25 l/h, 0.50 l/h, 0.75 l/h and 1 l/h were used to conduct this study. Thermography is a tool used in many scientific disciplines, including agriculture. This experimental study describes the application of thermography to determine the wetting patterns and water distribution in substrate culture. The results showed that in both growth media, the wetting was shaped like a rotating projectile, whose maximum wetting travel in horizontal was at 2 - 7 cm from the medium surface. When same irrigation volume was applied, the horizontal travel and vertical infiltration declined and rate of wetting rise with increase in emitter flow rate and horizontal wetting travel and vertical infiltration found enlarged in media dripped with low flow rate. Under the same irrigation application duration, increasing irrigation flow rate led to increase the horizontal and vertical wetting rate and travel. Under drip irrigation at same flow, there were increases in horizontal width and depth of the medium wetting body, decline in the wetting rate of wetting front, and horizontal rise in the progressively decreasing rate as the irrigation volume increases. Under drip irrigation of same duration and flow rate, the horizontal wetting rate of wetting front rise while the vertical infiltration rate was declined with increasing initial moisture content. Under the same drip flow rate, irrigation duration and initial moisture content, increasing packing densities (packed with maximal press that could be obtained by hand) of growth media limit the horizontal and vertical wetting rate of advancing front. |
| Year | 2018 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. Wm-18-26 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Water Engineering and Management (WM) |
| Chairperson(s) | Soni, Peeyush |
| Examination Committee(s) | Shrestha, Sangam;Babel, Mukand Singh;Datta, Avishek |
| Scholarship Donor(s) | World Bank / Punjab Agriculture Department, Pakistan |