Sustainable resource management is of central importance among agrarian societies in marginal drylands. In the Negev Desert, Israel, research on agropastoral resource management during Late Antiquity emphasizes intramural settlement contexts and landscape features. The importance of hinterland trash deposits as diachronic archives of resource use and disposal has been overlooked until recently. Without these data, assessments of community-scale responses to societal, economic, and environmental disruption and reconfiguration remain incomplete. In this study, micro-geoarchaeological investigations were conducted on trash mound features at the Byzantine-Early Islamic sites of Shivta, Elusa, and Nesanna to track spatiotemporal trends in the use and disposal of critical agropastoral resources. Refuse derived sediment deposits were characterized using stratigraphy, micro-remains (i.e., livestock dung spherulites, wood ash pseudomorphs, and plant phytoliths), and mineralogy by Fourier transform infrared spectroscopy. Our investigations detected a turning point in the management of herbivore livestock dung, a vital resource in the Negev. We propose that the scarcity of raw dung proxies in the studied deposits relates to the use of this resource as fuel and agricultural fertilizer. Refuse deposits contained dung ash, indicating the widespread use of dung as a sustainable fuel. Sharply contrasting this, raw dung was dumped and incinerated outside the village of Nessana. We discuss how this local shift in dung management corresponds with a growing emphasis on sedentised herding spurred by newly pressed taxation and declining market-oriented agriculture. Our work is among the first to deal with the role of waste management and its significance to economic strategies and urban development during the late Roman Imperial Period and Late Antiquity. The findings contribute to highlighting top-down societal and economic pressures, rather than environmental degradation, as key factors involved in the ruralisation of the Negev agricultural heartland toward the close of Late Antiquity.