Rare earth elements, an important kind of unrenewable natural resources, have been utilized extensively for socio-economic development in such fields as optics, electronic information, aerospace and nuclear industry, and other advanced science sectors.
I changed "rare earth" to "rare earth elements". I suppose your original sentence was right, but I have never heard the term "rare earth" used alone so it just sounded weird to me. Then, I changed "has" to "have" to match the plurality of "elements". I changed "one important kind" to "an important kind" because it sounds more natural (to me), but your original sentence is still correct. Finally, I changed "among" to "and". I think that the use of "among" would sound nice if the prior list had one or two items. So if it said "such fields as optics, among other advanced science sectors" or "such fields as optics and electronic information, among other advanced science sectors" it would sound fine, but in longer lists I wouldn't use "among".
At the moment, rare earth reserves in China account for 30% of total amount in the world. However, China's rare earth supply provides 97% of the market's needs.
I split this into two sentences right before "97%" because that is when you introduced a new topic (market needs). Generally, you don't want to start formal sentence with a number, so I changed the order of the sentence so the number wasn't in the beginning.
China is the top rare earth reserves holder in the world; by 2010, China's rare earth reserves had reached 36 million ton, 36.4% of the world rare earth reserves.
I changed the colon to a semicolon because it's dividing two thoughts (use a colon for lists "I have three favorite colors: red, green, and blue."). Have -> had because it's past tense.
China is also the top rare earth producer; by 2010, China's rare earth output had risen to 129000 tons, 97% of global output.
Same corrections as previous sentence. "ton" -> "tons"
Let me know if you have any questions!