Its probably jogging because your legs take on twice your weight when impacted on the ground each time, but for bikes, you just peddle lol. Also easy terrain on the bike might be hard for legs, so you'd get more excersize out of jogging, but not sure on calories.
Jogging burns a lot more, however walking for a longer period is better because it burns more than jogging.
I recommend running not on grass, or concrete, because grass puts more strain on the ankles to balance yourself, and concrete puts more pressure on the knees because its a hard surface. Something like a running track or a treadmill.
I think for the average person jogging will burn them more calories. Obviously though the harder and longer you maintain the exercise for determines how many calories you will lose.
The reason i go with jogging as the more effective way for the average person to burn calories is that they will generally able to go harder and faster when they jog because running is a more natural thing to do than riding. Cycling is often just as much a strength workout for the legs as it is a cardio exercise to boost lung capacity and burn calories.
