Bitcoin-derived blockchain has shown promise as infrastructure for many decentralized models. However, problems are withholding the realization of the potentials. The booming increase of storage demand has hindered devices with storage shortage to use blockchain powered distributed applications. In this paper, we present section-blockchain, a new blockchain protocol, which is designed to solve the oversize storage problem without compromise the security of blockchain. There are no full nodes or lightweight nodes, all nodes are equal and contributing to the Section-Blockchain network. Experiments demonstrate that Section-Blockchain is efficient, remarkably reduced the storage, and withstand sudden nodes losing of massive scale. Section-blockchain also extended the capability of blockchain to the foundation of an autotrophic, tamper-resist decentralized storage system, in which, data can be equidistributional distributed worldwide automatically without any centralized dispatcher to assign storage; nodes are motivated to change their local storage to receive more remuneration. The global storage distribution is continuously optimizing and fit into any adding/losing nodes.