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兰州市安宁堡、河口等地一向盛产大枣,仅安宁大队就曾年产200万斤,但是近年产量已减到几十万斤或十几万斤;河口的咸水川大队也由年产13—15万斤降至2—3万斤,特别是安宁公社砂井驿大队南坡坪生产队的数百株枣树,近十余年来由年产万斤变为颗粒无收。这是什么原因呢?看法不一。有的认为是管理不妥;有的认为是大气污染造成的;有的认为是气候的变化;有的人认为是病虫害造成的等等。根据我们几年来的观
Anning Fort in Lanzhou, estuaries and other places has always been rich in jujube, only the Anning Brigade had an annual output of 2000000 jin, but in recent years the output has been reduced to hundreds of thousands of jin or more than ten kilos; Estuarine salt water brigade also by an annual output of 13 -15 kg down to 2-3 million jins, especially in the peaceful commune Shajing Yi Brigade South slope production team hundreds of jujube trees, nearly 10 years from the annual output of 10,000 pounds into crop failure. What is the reason? Some think it is improper management; some think it is caused by air pollution; some think it is climate change; others think it is caused by pests and diseases and so on. According to our view of the past few years