Laserfiche WebLink
<br />~ <br /> <br />1 to be stocked .and maintained. To some extent, both, but particularly <br /> <br />2 drip systems, require diligent maintenance by skilled personnel. wnat <br /> <br />3 is obviously required, if the benefits of high-frequency irrigation are <br />. <br />4 to accrue to the nations that need to increase their food production <br />, ), <br />"'. <br />5 most urgently, is an inexpensive, simple system, that requires a low <br /> <br />6 level of energy and skiilto operate. Particularly if supplemental <br /> <br />7 irrigation is to be brought to. farmers practicing traditional agricul- <br /> <br />8 ture on small holdings in humid areas, the systems must be simple to <br /> <br />9 install and operate. <br /> <br />10 I've recently developed a system that shows promise of meeting <br /> <br />11 these requirements (7). It delivers water through inexpensive, 76- or <br /> <br />12 102-mm ID, buried corrugated polyethylene pipe laterals. Water is de- <br /> <br />13 livered from the lateral to fill a small basin (for example at the base <br /> <br />14 of a tree) through 9.S-mm ID, smooth-wall, polyethylene hose. Because <br /> <br />15 of their low cost the lateral pipes can be sized large enough to reduce <br /> <br />16 friction to the point that the system can operate from a water supply <br /> <br />17 less than I meter above the field. In many cases, the existing canals <br /> <br />18 could supply this pressure ~thout pumps. Outflow is precisely regulate <br /> <br />19 from each hose by fastening its outlet to a stake or a tree trunk at the <br /> <br />. <br />20 proper elevation. In addition to the pip~ and hose described, the field <br /> <br />21 distribution system consists of .only two other parts: a plastic, barbed- <br /> <br />22 tee connector stapled to. the stake or trunk of each tree, and a simple <br /> <br />23 O-ring coupler to join the 75- or 100-meter lengths of corrugated pipe. <br /> <br />24 By eliminating pumps, filters, sprinkler heads or emitters, and by <br />I <br /> <br />25 keeping the smallest diameter opening larger than 9 rum, the system <br /> <br />26 operates w~th less attention than most surface irrigation systems. And, <br /> <br />27 TN'here the water source is sufficiently elevated, at no more energy CQst. <br /> <br />Ou298:1 <br />