With low cost and high mobility, drones are envisioned to be an important contributor to emergency communications. In this paper, we consider a unique drone aided emergency communication deployed in hills and mountains areas, where power-constrained drones serve as relays to improve the uplink sum rates via amplify-and-forward (AF) relaying. The channel models between drones and ground users in this communications and the ground users distributions are greatly different from that in conventional relay networks, while drones have their coverage areas and capacity constraint. By taking these specific characteristics into account, we formulate the joint power and subcarrier allocation problem to maximize the uplink throughput in the drone aided emergency communications under constrains to the transmit power budget for each drone and the number of accessed users on each subcarrier. Due to the intractability of the formulated problem, it is decomposed into two subproblems: power allocation optimization and subcarrier allocation optimization. Then a joint resource allocation algorithm is proposed. The simulation results show that the proposed algorithm outperforms the others.