ZURICH (Reuters) – UBS announced changes to its executive board on Wednesday, with Aleksandar Ivanovic being named head of the bank’s $1.6 trillion asset management business. Ivanovic will replace Suni Harford, who is retiring in the change that is effective from March 1. Switzerland’s biggest lender also said Beatriz Martin Jimenez will become the Lead for Sustainability and Impact in addition to her existing responsibilities. The changes come as UBS continues its integration of Credit Suisse, which UBS bought for 3 billion Swiss francs ($3.46 billion) in an emergency rescue last year. Since …