Violating justice means being wrongly deprived of something that is rightfully ours. In no sense did the fall of Adam and Eve violate justice, either from Adam and Eve's point of view or from anyone (or anything) else's.
The earth was created primarily as a dwelling place for the children of God. The plants and animals of this world may be more than "mere chattel" (to use Hugh Nibley's phrasing), but they, indeed the elements themselves, are put here ultimately for the benefit of man. It's no more a violation of divine justice that their state was changed on the fall of Adam and Eve than a lion eating an antelope might be a violation of divine justice. Existence itself (in the sense we're talking about) is a gift from God. Neither animals nor plants nor the elements themselves have any "right" to exist in any given state. Even we as children of God have been granted rights of living only on the principles that God has established.
The whole business of salvation and atonement is based on the idea that we have lost whatever "rights" we may have possessed to eternal life and glory, and that God seeks to restore those to us. God strictly maintains divine justice at all times. He must necessarily do so; it's implicit in the term "God". He can only be a perfectly just Being, now and forever. But he has created for us a duration of space and time wherein we may choose and decide without immediately feeling the inevitable consequences of our actions. As the mortal Lord, the Great Judge himself in the flesh, told the sinful woman taken literally in the very act of adultery, "Neither do I condemn thee." This is not our time of judgment and condemnation. That is to come, when the Lord will surely condemn all those who do wickedly and do not repent. For now, we are granted a space of time to repent (2 Nephi 2:21, indeed all of 2 Nephi 2, 2 Nephi 9, Mosiah 2, Alma 5, and I guess all the rest of the scriptures and the teachings of the prophets, past and present).
If we repent and come to God, justice will pave our way to joy beyond measure. If we do not repent, justice will land us in the very situation we will have chosen. That is the justice of God, and it operates upon God's children. The rest of God's creations simply experience and fulfill his will in the spheres in which they have been placed.