Biotic Community

To understand what Leopold might mean by "biotic community" it will be helpful first to view natural objects as comprising a spectrum:

whatever it is that comprises subatomic particles

subatomic particles

atomic elements

molecules

inanimate objects

microbes and vegetative life

sentient life

sapient life

Each of these relies on its predecessors for the building blocks of its unique emergent properties, its developmental ancestry, and (importantly) its nurturance and continued existence/thriving. Ecology observes a previously neglected web of interrelationships between these things, most vitally between and among living things, as itself comprising a system, and thus possessing irreducible emergent properties. They term this meta-organismic whole an ecosystem or biosphere. We can in principle gauge its comparative state of health or unhealth by analogy with that of ordinary organisms, so although it almost invariably exceeds our comprehension it is not entirely mysterious to us, and "the good of the biotic community" is a meaningful, if often contestable, quality.