Add cover other than mulch before/after planting trees/shrubs: brackish/saline wetlands
Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
Background information and definitions
Planted vegetation may be damaged by hot, dry and bright conditions on bare wetland surfaces. Covers such as plastic mesh, sheets, or shelters for individual plants could ameliorate these factors and help planted vegetation to establish. The precise effect of covers may vary depending on the material used and how it is applied (e.g. to a large area vs individual plants; on the wetland surface vs suspended above the surface).
Related actions: Add cover other than mulch, other than to complement planting; Add surface mulch to complement planting; Use fences or barriers to protect planted areas from physical damage, e.g. with tree guards or breakwaters.
Supporting evidence from individual studies
A controlled study on a saltflat in western Mexico (Flores-Verdugo et al. 2015) reported that planted black mangrove Avicennia germinans seedlings grew faster when shaded than when exposed. Statistical significance was not assessed. Over six months, the height of seedlings planted in a partially-shaded area increased by 0.20 mm/day (from 7.1 cm when planted to 11.0 cm after six months. Meanwhile, the height of seedlings planted in unshaded areas increased by only 0.03–0.09 mm/day (from 6.5–7.2 cm when planted to 7.8–8.5 cm after six months). Methods: In August–September (year not reported), 600 nursery-reared black mangrove seedlings were planted alongside four excavated tidal channels on a bare saltflat. Seedlings were 50–100 cm apart. The 150 seedlings alongside one channel were shaded with black mesh, which blocked 50% of incoming light. The height of surviving seedlings was recorded for approximately six months.Study and other actions tested