Bellucia imperialis is one of the most abundant pioneer tree species in anthropized areas of the Central Amazon, and has ecological importance for the environmental resilience of phosphorus (P)-depleted areas. Thus, we investigated whether B. imperialis depends on symbiosis with arbuscular mycorrhizal fungi (AMF) to grow and establish under the edaphic stresses of low nutrient content and low surface moisture retention capacity of the substrate. We tried three AMF inoculation treatments: (1) CON—no mycorrhizae; (2) MIX—with AMF from pure collection cultures, and (3) NAT—with native AMF, combined with five doses of P via a nutrient solution. All CON treatment seedlings died without AMF, showing the high mycorrhizal dependence of B. imperialis. Increasing P doses significantly decreased the leaf area and shoot and root biomass growth for both the NAT and MIX treatments. Increasing P doses did not affect spore number or mycorrhizal colonization, but decreased the diversity of AMF communities. Some species of the AMF community showed plasticity, enabling them to withstand shortages of and excess P. B. imperialis was shown to be sensitive to excess P, promiscuous, dependent on AMF, and tolerant of scarce nutritional resources, highlighting the need to inoculate seedlings to reforest impacted areas.

The objective of this work is to present the costs of nucleation techniques in environment restoration from damaged areas due to oil exploration at the Geologist Pedro de Moura Operation Base – BOGPM, identified by Petrobras as LUC 15, JAZ 104 and JAZ 94. Three nucleation techniques were used: topsoil, artificial perches and dead wood/sticks. Nucleation consists in forming propagation nuclei in small strategic points of the area to be restored. The technique takes advantage of existing natural resources in the area, which reduces the cost of restoration. We registered the time of execution from each activity, the manpower and the input used. The data was analyzed by the method of Activity-Based Costing (ABC). For the three techniques, we found that cleaning of the damaged area was the activity that consumed more resources. For the topsoil technique, the activity of collection and transportation of the forest floor were also identified. The use of topsoil was the most costly technique, followed by the activities of dead woods/sticks and artificial perches respectively. We suggest the use of nucleation techniques to promote soil recovery to increase the number of propagule seedlings, to attract wildlife, and to act strategically in the landscapes, while minimizing erosion and costs.Key words: restoration cost, Activity Based Costing (ABC), nucleation, oil exploration.