在北美西北部整个海岸线上的黄杉数量都在下降，不管是在大陆还是在离岸的岛屿上。

Yellow cedars population has been declining all across the northwestern coast of north America, both on the mainland and on the islands just off the coast.

youdao

黄杉是北美西北部常见的树木。 但是从1880年开始的一个多世纪以来，黄杉的数量在逐渐减少。

Populations of the yellow cedar, a species of tree that is common in northwestern North America, have been steadily declining for more than a century now, since about 1880.

youdao

黄杉是北美西北部常见的树木。 但是从1880年开始的一个多世纪以来，黄杉的数量在逐渐减少。

Populations of the yellow cedar, a species of tree that is common in northwestern North America, have been steadily declining for more than a century now, since about 1880.

youdao