TPO 22 閱讀Spartina和Meteorite - 英檢

請問大家關於Spartina的最後一題
答案有包含第一個選項:
Spartina is very well adapted to conditions in salt marshes, where it plays a
valuable role in stabilizing them and making them highly productive marine
habitats.

我不太懂是後半段所說"making them highly productive marine habitats."
在文章前段應該是由於high tide所造成的現象，為何是Spartina所有的特色?



再來是The Allende Meteorite裡面最後一題
答案裡有:
"Except for being depleted in volatile elements, chondritic meteorites are
probably very similar in composition to the matter from which planets were
assembled."

可是回去原文的敘述，感覺只有和太陽相比的時候，才是缺乏Volatile elements
和一般行星比較之下:
" they are truly lumps of nebular matter, probably similar in composition to
the matter from which planets were assembled."
看來應該是去除了Volatile element之後才是和行星相像

希望能請大家解答
謝謝!

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