Final answer:
XML Schema based aspect implementation in Spring is used for implementing cross-cutting concerns in Spring AOP using XML configuration.
Step-by-step explanation:
The XML Schema based aspect implementation in Spring is used for implementing cross-cutting concerns in Spring AOP using XML configuration. It allows developers to define aspects, which are reusable modules of code that can be applied to multiple classes or methods. Aspects can be used for tasks such as authentication, logging, and transaction management in a Spring application.