In short, no. File ownership and access permissions are a kind of access control. Encryption and access control are orthogonal (here meaning "independent") concepts. Both are methods to implement/enforce authorization.
means that only agents in possession of the decryption key can gain access to the decrypted "plain text" of a file or data object. This access can be (temporarily) extended to other agents, e. g. users of the same system that holds the decryption key in memory.
means that an authority, e. g. an operating system running on a computer, decides who gets which kind of access to which resource (which may be a file, data object, or something else).
Why are they independent?
An operating system may know how to decrypt an encrypted data object to gain access to its plain text but that doesn't mean that it extends this access to all its users. It will commonly use access control databases to decide to whom to extend access (if at all).
Conversely, a user may have access to an encrypted dataset but, lacking a valid decryption key, cannot make any sense of it, i. e. cannot access its plain text. (This is not currently possible with any of the file systems and file system tools shipped with Ubuntu but such features are in development for out-of-the-box Ubuntu in the form of new ext4 features and already available in other file systems, e. g. ZFS and NTFS, albeit not necessarily on Linux.)