Explain the concept of isolation levels in DB2 and their significance in concurrency control.

Isolation levels in DB2 define the degree to which transactions are isolated from each other in terms of visibility of changes. Different isolation levels provide varying levels of consistency and concurrency control. For example, the highest isolation level, Serializable, ensures that each transaction sees a consistent snapshot of the database, even if other transactions are modifying data concurrently. However, this level of isolation can lead to increased contention and reduced concurrency. On the other hand, the lowest isolation level, Read Uncommitted, allows transactions to see uncommitted changes made by other transactions, maximizing concurrency but sacrificing consistency. Choosing the appropriate isolation level is crucial for balancing consistency and concurrency requirements in DB2 applications.