Multiply and Replenish the Earth

So I watched the movie Noah for the first time tonight and the last line got me thinking "Multiply and Replenish the Earth."
Often in the world we focus on the multiply bit where families are concerned. My thoughts turn to the replenishing bit. How do we replenish the Earth? Or do we forget we are stewards over the Earth and it is our to tend and take care of? Do we plant trees, flowers, things that will help sustain the planet? Or do we think that because we are human the earth is ours to use as we will? Do we, in our selfishness deplete the Earth of all of its goodness? What will be left for our children? Our grand children? Our great grand children?
I know I'm just as guilty as the next person and I don't mean to preach. I will however resolve to do better in my gardening, in my taking care of the Earth. I'm not sure how much my little bit will help, but I hope to be a little better each day at replenishing the Earth. For it is, as we are, in a constant cycle needing nourishment and water. If we provide these things it, just like us, transforms into something beautiful and glorious. For we are created by a God who loves us.