Which risk increases when pre-Columbian terraced irrigation systems experience prolonged drought?

💡 Explanation

When prolonged drought stresses terraced systems, soil moisture decreases, initiating dry raveling due to weaker cohesion, which mobilizes topsoil. Therefore, topsoil erosion increases, rather than the alternative outcomes which require increased moisture or specific chemical compositions and mechanisms not present during drought.

• Which mechanical process allowed Roman roads to maintain a relatively uniform grade across sloped terrain?
• Which environmental transformation resulted from the extensive terrace cultivation practices employed by the Inca civilization?
• Which risk increases when bronze bucket chain dredges encounter abrasive river sediments?
• Which effect limits positional accuracy when an astrolabe's altitude scale shifts due to thermal expansion?
• Which structural failure mode most critically threatened the stability of the Crystal Palace during high winds?
• Which outcome occurred when bronze-age metallurgists smelted arsenical copper ore without proper ventilation?