The dust bowl and caused by dieing plants and pestisides
By banning people from visiting Palastine. I think that's the answer.
Wu Zhao lowered taxes, and increased food production. Also Wu funded public projects and tried to reduce the power of the military in China. Wu also replaced aristocratic military men with scholar-officals.
It was important because it was marked by extensive discoveries and inventions in Science, Technology, Engineering, Art, Dialectic, Literature, Logic, Mathematics, Astronomy, Religion and Philosophy.