It was this that made the organization of irrigation, particularly the building of canals to channel and preserve the water, essential.
正是这点使得灌溉的统筹，特别是建造运河以疏导和保护水，变得至关重要。
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Since most planetary scientists believe that water is essential to life, the presence of jarosite means that one prerequisite for life was once present on Mars.
Since the northeast region of North American is interconnected by many streams and waterways, water transportation by vessels like a canoe was most essential.