Effect Of Drippers Space On The Soil Wetting Uniformity Under Linear-source Drip Irrigation

Based on experiments,the influence of drippers spacing on soil moisture uniformity from linear source drip irrigation were studied. The experiments involved two soil types (sandy soil and silt loam),drippers spacing being in the range of 10cm-70cm, and with the dripper discharge and dripping water volume being constant. Through observing and analysing the (?)ize of wettting body, movement of wetting fronts and distribution of water in wetting sphere. Besides, this paper analysed the effection of dripping water discharge on these quotas of sandy soil and silt loam. Conclusions are as follows:1) with the same dripping water volume and dripper discharge, the effection of soil type on wetting pattern is obviously. With dripper discharge increasing, the wetting body of sandy soil gets narrower and deeper, that of the silt loam is widder and shallower. The wetting front of sandy soil gets more deeper and with the bottom gets more ever. Silt loam has no obvious effect on wetting(2) drippers spacing has different effect on soil moisture uniformity of sandy soil and silt oam with dripper discharge and dripping water volume constant.the experiment result showing that drippers spacing has no obvious effect on soil moisture uniformity of silt loam. The moisture uniformity of sand soil along drip line did not obviously decrease until drippers spacing exceeded 30cm,and its moisture uniformity across drip line and on the intersection side of wetted fronts were not dominantly influenced by drippers spacing, but the soil water (?)olume of wetted fronts intersection area was in reduced obviously with drippers spacing ncreased.(3) according to the regularity of water distribution in wetting body, the relation of drippers spacing and sand soil moisture uniformity is derived based on Christiansen formula.In a word, drippers spacing has dominant effect on the moisture uniformity of sandy soil along drippers line. This moisture uniformity is a very important quota for quality appraising of linear source drip irrigation. The results of this study are useful to the design of drip rrigation system and quality appraising of linear source drip irrigation...