Succession of seawall algal communities on artificial substrates
-
Published source details
Loke L.H.L., Liao L.M., Bouma T.J. & Todd P.A. (2016) Succession of seawall algal communities on artificial substrates. Raffles Bulletin of Zoology, 32, 1-10.
Published source details Loke L.H.L., Liao L.M., Bouma T.J. & Todd P.A. (2016) Succession of seawall algal communities on artificial substrates. Raffles Bulletin of Zoology, 32, 1-10.
Actions
This study is summarised as evidence for the following.
| Action | Category | |
|---|---|---|
|
Create grooves and small protrusions, ridges or ledges (1–50 mm) on intertidal artificial structures Action Link |
 |
|
|
Create pit habitats (1–50 mm) on intertidal artificial structures Action Link |
|
-
Create grooves and small protrusions, ridges or ledges (1–50 mm) on intertidal artificial structures
A replicated, randomized, controlled study in 2011–2012 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke et al. 2016; same experimental set-up as Loke et al. 2017) reported that concrete settlement plates with groove habitats and small ridges, along with pits, supported higher macroalgal species richness but similar abundances compared with granite plates without added habitats. After 12 months, settlement plates with grooves, ridges and pits supported a total of five macroalgal species groups, while plates without supported three (data not statistically tested). Abundances of three species groups were statistically similar on plates with added habitats (18–41% cover) and without (5–61%) in five of six comparisons, while one group was more abundant on plates with added habitats (22–27 vs 5%) at one site. Abundances were similar on plates with variable (1–34%) and regular (3–41%) habitats. It is not clear whether these effects were the direct result of creating grooves, ridges or pits. Settlement plates (400 × 400 mm) were moulded with groove habitats and small ridges, with pits, and with neither. Plates with grooves, ridges and pits were concrete with four-to-five concentric circular grooves and ridges/plate or 36 pits/plate. Grooves, ridges and pits had either regular (32 mm width, depth/height and spacing) or variable (8–56 mm) arrangement. Plates without grooves, ridges or pits were granite fragments set in cement. Granite may be considered an environmentally-sensitive material compared with concrete (see “Use environmentally-sensitive material on intertidal artificial structures”). Five of each design were randomly arranged at lowshore on each of two granite boulder seawalls in July 2011. Macroalgae on plates were counted from photographs after 12 months.
(Summarised by: Ally Evans)
-
Create pit habitats (1–50 mm) on intertidal artificial structures
A replicated, randomized, controlled study in 2011–2012 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke et al. 2016; same experimental set-up as Loke et al. 2017) reported that concrete settlement plates with pit habitats, along with grooves and small ridges, supported higher macroalgal species richness but similar abundances compared with granite plates without added habitats. After 12 months, settlement plates with pits, grooves and ridges supported a total of five macroalgal species groups, while plates without supported three (data not statistically tested). Abundances of three species groups were statistically similar on plates with pits, grooves and ridges (18–41% cover) and without (5–61%) in five of six comparisons, while one group was more abundant on plates with pits, grooves and ridges (22–27 vs 5%) at one site. Abundances were similar on plates with variable (1–34%) and regular (3–41%) habitats. It is not clear whether these effects were the direct result of creating pits, grooves or ridges. Settlement plates (400 × 400 mm) were moulded with pit habitats, with grooves and small ridges, and with neither. Plates with pits, grooves and ridges were concrete with 36 square pits/plate or four-to-five grooves and ridges/plate. Pits, grooves and ridges were either regular (32 mm width, depth/height and spacing) or variable (8–56 mm). Plates without pits, grooves or ridges were granite fragments set in cement. Granite may be considered an environmentally-sensitive material compared with concrete (see “Use environmentally-sensitive material on intertidal artificial structures”). Five of each design were randomly arranged at lowshore on each of two granite boulder seawalls in July 2011. Macroalgae on plates were counted from photographs after 12 months.
(Summarised by: Ally Evans)
