What's the difference between 遭到 and 遭受?
遭: encounter; suffer; receive

到:  verbal particle to indicate the result of an action.

遭到 (receive; encounter) is a verb 遭 (encounter) +  a verb particle 到. There is only one verb 遭.


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遭: receive; encounter; suffer

受: receive

遭受 is a compound word (single word) for 'receive; suffer; undergo'


Since 遭受 is a single verb, you can add verb particle 到 after it to indicate the result and write 遭受到.
On the other hand, 遭到 is a verb and its verb particle, you can omit the verb particle and only write 遭 when you don't need to emphasize the result of the verb
The following are all valid sentences. They all mean the same:

生态平衡遭受破坏。(the compound word verb 遭受 is more specific than the single character verb 遭)


生态平衡遭受到破坏。 (the verb particle 到 indicates the verb 遭受 is completed/ received a result


生态平衡遭破坏。(using the literary single character verb 遭 make it sounds more classical/ literary)


生态平衡受破坏。(using the colloquial single character verb 受 make it sounds more modern/ colloquial)


生态平衡遭到破坏。(the verb particle 到 indicates the verb 遭 is completed/ received a result, also make it sounds more modern/ colloquial)


You can replace 遭到 (more literary) with 受到 (more colloquial)