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农业生产活动与地理环境

> 新疆的哈密瓜特别甜，而同一品种在北京采用大棚种植则甜度下降，这是因为大棚种 ①温度偏低 ②水分偏少 ③温差较小 ④光照减弱 A．①② B．②④ C．③④ D．①③

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发布时间：2024-09-11

新疆的哈密瓜特别甜，而同一品种在北京采用大棚种植则甜度下降，这是因为大棚种
①温度偏低 ②水分偏少 ③温差较小 ④光照减弱

A．①② B．②④ C．③④ D．①③

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