maritime activity meaning in English

海事活动

The book is filled with descriptions of ghosts and monsters , but it is of great value to the studies of zheng he and his maritime activities
书中虽然穿插了许多神魔故事侈谈怪异，但是对于郑和及其航海行动的研究却具有很大意义。
But the negative impact is that it violated the rules of economic development inherent in maritime activities , and caused ill effect to the elevation of ming dynasty ' s national strength and the timely transformation of china ' s social and economic system , therefore the good situation in navigation cause since song and yuan periods came to a sudden end , and china , locking her doors against the world and under the eastward aggression of western colonists , plunged into the miseries of backwardness and humiliation
郑和下西洋负面的消极历史作用主要是：违背了远洋航海活动内在应循的经济性发展规律，对明王朝综合国力的提升和中国社会经济制度的适时转型造成了不良影响，以致使宋元以来航海事业蓬勃发展的大好势头戛然而止，并在闭关锁国政策和西方殖民东侵的内外钳制下，逐步陷于落后被打的悲惨境地。