Nature lovers embraced their emerald empire with a daylong showcase of fun and festivity for “It’s Our Park Day” at Kaiser Park. The outdoor celebration drew mom, dad and kids to the sprawling green – bounded by Neptune and Bayview avenues and West 24th and West 25th streets – where they enjoyed hours of simple pleasures; among them, a talent show, sports tournaments, music and air rides. The annual spectacle – part of National Parks Day celebrations – was presented locally by Friends of Kaiser Park to the theme of, “Fitness is Fun.”