Is reviving barren land and cultivating it, knowing that it is part of a larger tract of land that was previously under a usufruct contract with another person, and then parts of it were appropriated by the state, considered a revival of dead land or usurpation?

The holder of land under a usufruct contract is not permitted to sell it, because he does not own it; it is a loan for his use only. Therefore, the sale is void unless approved by the responsible authority. Reclamation (ihya’) applies to land that is not previously owned by anyone, and it becomes the property of the one who reclaims it by watering, planting, cultivating, or building on it. The land in question is not barren (mawat), so it is not permissible to reclaim it or dispose of it without the permission of the responsible authority. It is advisable to consult the scholars of the country to ascertain the details of local laws.