Reed-straw configuration density in Suaeda salsa restoration: Context-dependent biological responses under controlled flooding

Locally sourced reed straw may provide a biodegradable, near-natural aid for re-establishing Suaeda salsa on hydrologically variable salt-marsh surfaces. We screened no mulch and 1-, 2-, and 3-cm anchored, cross-woven configurations across three flooding depths and three daily inundation durations. The split-plot experiment comprised 36 independently operated tanks and 144 separate pots. The implemented configurations differed in standing seedling proportion, plant height, root biomass, and total biomass, and several configuration contrasts changed with hydrological treatment. A quasi-binomial mixed-model sensitivity analysis supported the early seedling result, while per-pot analyses supported the biomass result. No configuration was consistently superior, and none of the 27 hydrology-specific day-9 or day-90 treatment-versus-control contrasts remained significant after Holm adjustment. The descriptive pattern supports carrying the 2- and 3-cm configurations forward for direct comparison in a subsequent validation study; it does not establish an optimum. The experiment is therefore a controlled screen of a composite reed-straw configuration, not a test of spacing geometry alone or a field-ready restoration prescription.