The arid-valley scrubs formed in the time and space of the special habitat and geological history,was a intrazonal(azonal or extrazonal)vegetation of similar to aestatifruticeta-steppe in between the forest and steppe.

• 干旱河谷灌丛形成于特定的生态环境和地质历史的时空中,是一种处于森林与草原之间的而近似于草原灌丛的隐域性(非地带性或超地带性)植被。