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美刊《灌溉新闻》1981年7月两期报道了美国一些州由于严重缺水而出现的局面,以及采取的节水措施。 美国仅仅灌溉一项就占全国总耗水量的81％,灌溉耗水的53％取自地下水。全国正面临着水危机,农业、工业和城市之间在争夺用水。情况清楚地表明,农业必须改变以往充分灌水的传统,以节约用水。有远见的菜农已经在探索试用种种节水的生产技术。 滴灌不仅是对作物需水的根部施水,而且还不使作物顶部过湿而招致病害。通过滴灌系统可以向土壤施加肥料、杀菌和灭虫剂。滴灌系统的缺点是基建投资高。有不少农场已经在使用混凝土管以减少基建投资。滴灌的应用正在扩大,是有前途的。 有越来越多的菜农采用结合滴灌加盖塑料膜的办法。盖薄膜可以减少蒸发,既可以省水,又可以增加降低成本的效益,有一个种茄子采用这种办法的实例,茄子产量增加了两倍。
The July issue of July 1981 in the U.S. Journal Irrigation News covered the situation of some states in the United States due to severe water shortages and the water conservation measures they adopted. The United States alone accounts for 81% of the country’s total water consumption and 53% of the water used for irrigation comes from groundwater. The country is facing a water crisis, with agriculture, industry and cities competing for water. The situation clearly shows that agriculture must change its tradition of full irrigation in order to save water. Farmers who have foresight have been exploring the trial of various water-saving production techniques. Drip irrigation not only imparts water to the root of the crop, but it also does not cause the top of the crop to get wet and cause disease. Fertilizers, bactericides and insecticides can be applied to the soil through drip irrigation systems. The disadvantage of drip irrigation systems is the high capital investment. Many farms already use concrete pipes to reduce capital investment. Drip irrigation is expanding and promising. There are more and more farmers using a combination of drip irrigation plastic film approach. Cover film can reduce evaporation, can save water, but also can reduce the cost benefits, there is an example of such a method of eggplant, eggplant production tripled.