  In harsh environments, organisms may self-organize into spatially patterned
systems in various ways. So far, studies of ecosystem spatial self-organization
have primarily focused on apparent orders reflected by regular patterns.
However, self-organized ecosystems may also have cryptic orders that can be
unveiled only through certain quantitative analyses. Here we show that
disordered hyperuniformity as a striking class of hidden orders can exist in
spatially self-organized vegetation landscapes. By analyzing the
high-resolution remotely sensed images across the American drylands, we
demonstrate that it is not uncommon to find disordered hyperuniform vegetation
states characterized by suppressed density fluctuations at long range. Such
long-range hyperuniformity has been documented in a wide range of microscopic
systems. Our finding contributes to expanding this domain to accommodate
natural landscape ecological systems. We use theoretical modeling to propose
that disordered hyperuniform vegetation patterning can arise from three
generalized mechanisms prevalent in dryland ecosystems, including (1) critical
absorbing states driven by an ecological legacy effect, (2) scale-dependent
feedbacks driven by plant-plant facilitation and competition, and (3)
density-dependent aggregation driven by plant-sediment feedbacks. Our modeling
results also show that disordered hyperuniform patterns can help ecosystems
cope with arid conditions with enhanced functioning of soil moisture
acquisition. However, this advantage may come at the cost of slower recovery of
ecosystem structure upon perturbations. Our work highlights that disordered
hyperuniformity as a distinguishable but underexplored ecosystem
self-organization state merits systematic studies to better understand its
underlying mechanisms, functioning, and resilience.
