Zhouqu immigrants move during the Spring Festival.

(1) Natural causes: ① geology and landform; The mountains are high and deep, faults are developed in the mountains, and the mountains are broken; ② Meteorological reasons; Heavy precipitation in a short time. Man-made reasons: due to deforestation, the vegetation is seriously damaged.

(2)① Afforestation; (2) The project construction and village location layout should avoid the valley areas prone to mudslides; ③ Establish slope protection and retaining wall; (4) Rock mass transformation and drainage; ⑤ Migration and relocation. (Answer any two correctly)