In another Pool A match, New Zealand twice came from behind to defeat Canada 3-2.
Taekema collected the first hat trick at this event with goals in the 14th, 35th and 61st minutes for the three-time champions.
"I'm not after personal landmarks. My ambition is to help the Netherlands clinch the World Cup," said Taekema, who was not a member of the Dutch team when it last won the World Cup in 1998.
Germany, the Olympic gold medalist and No. 1 ranked team, was rattled by South Korea's attacking game but came back through two lucky goals in the second session.
Hyun Hye-sung converted a penalty corner for the Asian champions in the fourth minute, and Lee Nam-yong capped his solo run down the left flank by beating goalkeeper Max Weinhold from an acute angle in the 15th.
"We played the first half well, but Germany came back hard in the second half," South Korea coach Shin Seok-kyo said.
Germany responded when Florian Fuchs deflected a rising ball into the goal in the 50th minute. Benjamin Wess equalized after a goal-mouth scramble in the 58th.
"I must admit, we were lucky to draw this match," Germany captain Max Muller said. "But we're happy with the way we have managed to fight back and create chances.
"But we must improve our penalty corners. We wasted six today. That is something we can't afford to do in our remaining matches." Ryan Archibald scored from the top of the striking circle three minutes from fulltime to give New Zealand victory in another Pool A match.
Canada scored first through Mark Pearson's second-minute strike, but New Zealand's Priyesh Bhana equalized in the 11th minute.
Canada went into the interval 2-1 up after Philip Wright's opportunistic shot in the 20th.
New Zealand dominated in midfield in the second session and leveled through a penalty corner by Nick Haig in the 46th.
