Contemporary market-based (i.e. neoliberal) 'green economy' approaches to environmental degradation emphasise exchanges whereby quantified units of environmental harm are traded or 'offset' for compensating units of environmental health. Also encouraged is a view that economic growth can be 'greened' through 'decoupling' economic value from material ecological realities. Such approaches tend to frame biophysical natures in terms of aggregates, such as an 'aggregate natural capital rule' and 'net zero carbon.' Naturesbeyond-the-human are thereby understood and enacted as calculable, exchangeable, substitutable and commensurable between different spatial and temporal sites, making up an 'aggregate' or 'net' value overall. This article uses a comparative cross-cultural engagement to problematize ontological assumptions regarding the nature of nature underscoring the rationality of these aggregating and offsetting 'solutions.' Drawing on literatures from environmental anthropology and environmental ethics, combined with ethnographic material from long-term field research in north-west Namibia, the article considers elements of alternative cultural ontologies and the ways these may give rise to a different array of practices with value for conceiving and generating 'sustainability.' It adheres to a critical political ecology perspective in understanding the ways that power structures the ontologies that become both privileged and occluded in neoliberal strategies for green economy governance. In doing so, the article argues that sensitivity to the ontological politics through which spaces and entities are defined and known and which thereby shape environmental conflicts, may be key to recognising with more depth the sometimes significantly different 'natures' being struggled over in such conflicts. Key words: ontology; green economy; offsetting; decoupling; sustainability; value; natures-beyond-thehuman; neoliberalism; political ecology RĂ©sumĂ© Les approches de la dĂ©gradation de l'environnement fondĂ©es sur le marchĂ© et l'Ă©conomie verte mettent l'accent sur les Ă©changes, dans le cadre desquels des unitĂ©s quantifiĂ©es de dommages Ă l'environnement sont Ă©changĂ©es ou «compensĂ©es» pour compenser des unitĂ©s de santĂ© environnementale. On encourage Ă©galement l'idĂ©e que la croissance Ă©conomique peut ĂȘtre «vernie» par le biais du «dĂ©couplage» de la valeur Ă©conomique des rĂ©alitĂ©s Ă©cologiques matĂ©rielles. De telles approches tendent Ă encadrer les natures biophysiques en termes d'agrĂ©gats, tels qu'une «rĂšgle du capital naturel agrĂ©gé» et un «carbone zĂ©ro net». Les natures-au-delĂ de l'humain sont ainsi comprises et promulguĂ©es comme calculables, Ă©changeables, substituables et commensurables entre diffĂ©rents sites spatiaux et temporels, constituant une valeur «agrĂ©gĂ©e» ou «nette». Cet article utilise un engagement interculturel comparatif pour problĂ©matiser les hypothĂšses ontologiques concernant la nature de la nature, soulignant la rationalitĂ© de ces «solutions» d'agrĂ©gation et de compensation.