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50年代以后,美国佛州对柑桔灌溉的看法已经改变。Savage(1953)认为,柑桔不值得灌溉。即灌溉使产量增加所获得的效益,通常不足以补偿其成本费用。原因是:①50年代佛州栽植距离较大,间距为30×30呎或25×25呎;②广泛应用长势旺盛的粗柠檬砧,能从较大的土壤容积中吸收水份;③50年代佛州柑桔栽培区的年降雨量一般比正常的高。近年,随着砧木的改变、栽植距离较小以及灌溉技术的改进,
After the 1950s, Florida’s perception of citrus irrigation in Florida has changed. Savage (1953) believes that citrus is not worth irrigating. That is, the benefits of irrigation to increase production are often not enough to cover their costs. The reason is: ① 50 years Florida planted a larger distance of 30 × 30 feet or 25 × 25 feet; ② extensive use of growing rough lemon anvil, can absorb water from a larger soil volume; ③ 1950s Florida Annual rainfall in citrus cultivation is generally higher than normal. In recent years, with changes in rootstocks, planting distances and improvements in irrigation technology,