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Why Do Desert Plants Bloom Only After Rare Heavy Rains?
为什么沙漠植物只在罕见的暴雨后开花？
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Desert plants like ocotillo and desert lilies remain dormant for months or even years underground.
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Their seeds contain biochemical inhibitors that prevent germination until heavy rain washes them away.
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Soil moisture must reach a critical threshold to trigger hormonal signals for rapid growth.
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This adaptation avoids wasting energy on flowers if rain is too brief or shallow for root establishment.
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Some species bloom within 48 hours after rainfall, completing their entire life cycle in under six weeks.
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Bees and moths synchronize their activity with these short-lived floral displays for pollination.
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Scientists study seed coat chemistry to understand how drought tolerance evolved in arid zones.
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Climate change may disrupt this timing by altering rainfall intensity and seasonal distribution.
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Remote sensing helps track bloom events across vast deserts where ground observation is difficult.
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These ephemeral blooms support entire food webs, including insects, birds, and small mammals.