地理漫步·世界地理英语30篇（4）
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The Chihuahuan Desert: Basin-and-Range Topography and Ephemeral Playa Hydrology
奇瓦瓦沙漠：盆岭地貌与间歇性盐湖水文
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Stretching across northern Mexico and southwestern US, this desert features alternating mountain ranges and sediment-filled basins.
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Rainfall rarely penetrates deeply, so most water flows across surfaces toward closed depressions called playas.
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Playa floors hold evaporite minerals like gypsum and halite deposited during brief flooding episodes.
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Wind erodes exposed playa sediments, generating dust storms that affect air quality hundreds of kilometers away.
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Aquifers beneath basins rely on rare recharge events funneled through fractured limestone ridges bordering the desert.
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Vegetation bands follow subtle elevation changes where subsurface moisture concentrates near basin edges.
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Fault-controlled topography directs runoff paths, making flash floods highly localized and geomorphically significant.
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Soil salinity gradients mirror distance from playa centers, shaping plant community zonation patterns.
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Nighttime temperature drops cause dew condensation on desert pavements, sustaining cryptobiotic soil crusts.
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Remote sensing detects seasonal soil moisture pulses invisible to ground observation but critical for seed germination.