God himself is the Creator of the world and creation is not yet finished.  God works:POPE BENEDICT XVI.

1.  What  contribution can Christians make toward a humane environment?

Christians are not environmentalists if their commitment is limited to moral appeals made to others.  It is just as unhelpful to talk constantly about global problems instead of paying close attention to one’s own environment and the possibilities present in it.  Christian environmental ethics, therefore, is not built on smug appeals. Instead, it tries to provide orientation concerning individual and societal conflicts that need to be resolved.  For this purpose, the must be first of all a precise analysis of cause –and-effect connections, risks, and prospects. Only then can guiding principles be effective. Christians make a valuable contribution to the preservation of the ecosystem when they care for creation instead of venting frustration about the environment.  The courage to hope must be combined with the search for knowledge and the readiness to act.       

2.  What does it mean to  “be good stewards of creation” ?

“Being good stewards of creation” cannot mean that we as Christians are supposed to preserve all of nature as an object of our care.  Nature is an open, continuously evolving system and not an array of static conditions to be maintained. Only there is a more exact theological, ecological, economic, aesthetic, or cultural description of what aspects of nature are worth preserving can there be meaningful reflection about what should be protected and tended, and when, why, and how  that can be done.      

Fr. Michael