河狸,大自然的工程师河狸是当之无愧的自然工程师:它们切割树木,吃掉树皮之后,还用剩下的树枝来构筑堤坝,贮存一年中雨天的降水,因此对于调节水系的流水量具有十分重要的作用:在夏季的丰水期,从山上冲下来的洪水被部分保持在堤坝后面的池塘中;在冬季的枯水季节,由于堤坝具有渗漏性,其所蓄的水又慢慢流往下游地区,给溪流增加水量。更为重要的是,许多被流水裹挟而来的沉积物,都慢慢堆积在堤坝后面 Beavers, Nature’s Engineers Beaver is a well-deserved natural engineer: they cut the trees, eaten the bark, built the levees with the rest of the branches, and stored precipitation for a year in rainy days, thus regulating the flow of water Has a very important role: during the summer months, floods washed down from the hills are partially retained in the pond behind the levee; in the dry season of winter, the water stored in the dyke is slow due to its seepage Slow flow to downstream areas, to increase the water flow. More importantly, many of the sediments that are trapped by water flow slowly accumulate behind the dam