Study

Structural complexity and component type increase intertidal biodiversity independently of area

  • Published source details Loke L.H.L. & Todd P.A. (2016) Structural complexity and component type increase intertidal biodiversity independently of area. Ecology, 97, 383-393.

Actions

This study is summarised as evidence for the following.

Action Category

Create small protrusions (1–50 mm) on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures

Create small ridges or ledges (1–50 mm) on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures

Create grooves and small protrusions, ridges or ledges (1–50 mm) on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures

Create small protrusions (1–50 mm) on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures

Create small ridges or ledges (1–50 mm) on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures

Create grooves and small protrusions, ridges or ledges (1–50 mm) on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures

Create pit habitats (1–50 mm) on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures

Create pit habitats (1–50 mm) on intertidal artificial structures

Action Link
Biodiversity of Marine Artificial Structures
  1. Create small protrusions (1–50 mm) on intertidal artificial structures

    A replicated, randomized, controlled study in 2009–2010 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke & Todd 2016a; same experimental set-up as Loke & Todd 2016b) found that concrete settlement plates with small protrusions supported higher macroalgae and invertebrate species richness but similar community composition and abundances compared with granite plates without protrusions. After 13 months, macroalgae and invertebrate species richness was higher on settlement plates with small protrusions (8 species/plate) than without (3/plate), while abundances were statistically similar (88 vs 178 individuals/plate). Community composition was similar on plates with and without protrusions (data reported as statistical model results). Settlement plates (200 × 200 mm) were moulded with and without small protrusions. Plates with protrusions were concrete with 36 cylindrical protrusions/plate with either regular (16 mm width, height and spacing) or variable (4–28 mm) arrangement. Plates without protrusions 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”). Eight of each design were randomly-arranged at both lowshore and highshore on each of two granite boulder seawalls in November–December 2009. Macroalgae on plates were counted from photographs and invertebrates in the laboratory after 13 months.

    (Summarised by: Ally Evans)

  2. Create small ridges or ledges (1–50 mm) on intertidal artificial structures

    A replicated, randomized, controlled study in 2009–2010 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke & Todd 2016a; same experimental set-up as Loke & Todd 2016b) found that concrete settlement plates with small ridges supported similar macroalgae and invertebrate community composition, species richness and abundance to granite plates without ridges. After 13 months, macroalgae and invertebrate community composition (data reported as statistical model results), species richness and abundance were statistically similar on settlement plates with small ridges (6 species/plate; 97 individuals/plate) and without (3 species/plate, 178 individuals/plate). Settlement plates (200 × 200 mm) were moulded with and without small ridges. Plates with ridges were concrete with 12 serrated ridges/plate, with either regular (16 mm width, height and spacing) or variable (4–28 mm) arrangement. Plates without 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”). Eight of each design were randomly arranged at both lowshore and highshore on each of two granite boulder seawalls in November–December 2009. Macroalgae on plates were counted from photographs and invertebrates in the laboratory after 13 months.

    (Summarised by: Ally Evans)

  3. Create grooves and small protrusions, ridges or ledges (1–50 mm) on intertidal artificial structures

     A replicated, randomized, controlled study in 2009–2010 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke & Todd 2016a; same experimental set-up as Loke & Todd 2016b) found that concrete settlement plates with groove habitats and small ridges supported different macroalgae and invertebrate community composition with higher species richness but similar abundances compared with granite plates without grooves and ridges. After 13 months, macroalgae and invertebrate species richness was higher on settlement plates with grooves and ridges (8 species/plate) than without (3/plate), while abundances were statistically similar (126 vs 178 individuals/plate). Community composition differed on plates with and without grooves and ridges (data reported as statistical model results). Settlement plates (200 × 200 mm) were moulded with and without groove habitats and small ridges. Plates with grooves and ridges were concrete with four-to-five concentric circular grooves and ridges/plate with either regular (16 mm width, depth/height and spacing) or variable (4–28 mm) arrangement. Plates without grooves and 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”). Eight of each design were randomly arranged at both lowshore and highshore on each of two granite boulder seawalls in November–December 2009. Macroalgae on plates were counted from photographs and invertebrates in the laboratory after 13 months.

    (Summarised by: Ally Evans)

  4. Create small protrusions (1–50 mm) on intertidal artificial structures

    A replicated, randomized, controlled study in 2009–2010 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke & Todd 2016b; same experimental set-up as Loke & Todd 2016a) found that concrete settlement plates with small protrusions, along with grooves, small ridges and pits, supported higher macroalgae and invertebrate species richness than granite plates without added habitats, but that abundances and community composition varied depending on the habitat arrangement, shore level and site. After 13 months, macroalgae and invertebrate species richness was higher on settlement plates with protrusions, grooves, ridges and pits than without at lowshore (13–23 vs 6–10 species/plate) and highshore (5–9 vs 2–3/plate). Richness was higher on plates with variable habitats than regular ones at lowshore (22–23 vs 13–16/plate), but not highshore (6–9 vs 5–6/plate). Abundances were higher on plates with added habitats than without in four of eight comparisons (9–833 vs 3–208 individuals/plate), while community composition differed in three of four comparisons (data reported as statistical model results). In all other comparisons, results were similar (abundances: 104–1,957 vs 49–1,162/plate). It is not clear whether these effects were the direct result of creating protrusions, grooves, ridges or pits. However, plate quarters with protrusions had similar richness (8 species/quarter) and abundances (88 individuals/quarter) to quarters with the other habitat types (6–11 species and 97–231 individuals/quarter). Settlement plates (400 × 400 mm) were moulded with and without small protrusions, along with grooves, small ridges and pits. Plates with added habitats were concrete. Each 200 × 200 mm quarter contained either 36 cylindrical protrusions, four-to-five grooves and ridges, 12 ridges or 36 pits. All habitats had either regular (16 mm width, depth/height and spacing) or variable (4–28 mm) arrangement. Plates without added habitats 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”). Eight of each design were randomly arranged at both lowshore and highshore on each of two granite boulder seawalls in November–December 2009. Macroalgae on plates were counted from photographs and invertebrates in the laboratory after 13 months.

    (Summarised by: Ally Evans)

  5. Create small ridges or ledges (1–50 mm) on intertidal artificial structures

    A replicated, randomized, controlled study in 2009–2010 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke & Todd 2016b; same experimental set-up as Loke & Todd 2016a) found that concrete settlement plates with small ridges, along with grooves, small protrusions and pits, supported higher macroalgae and invertebrate species richness than granite plates without added habitats, but that abundances and community composition varied depending on the habitat arrangement, shore level and site. After 13 months, macroalgae and invertebrate species richness was higher on settlement plates with ridges, grooves, protrusions and pits than without at lowshore (13–23 vs 6–10 species/plate) and highshore (5–9 vs 2–3/plate). Richness was higher on plates with variable habitats than regular ones at lowshore (22–23 vs 13–16/plate), but not highshore (6–9 vs 5–6/plate). Abundances were higher on plates with added habitats than without in four of eight comparisons (9–833 vs 3–208 individuals/plate), while community composition differed in three of four comparisons (data reported as statistical model results). In all other comparisons, results were similar (abundances: 104–1,957 vs 49–1,162/plate). It is not clear whether these effects were the direct result of creating ridges, grooves, protrusions or pits. However, richness was lower on plate quarters with ridges (6 species/plate) than pits (11/plate), but similar to quarters with protrusions and with grooves and ridges (both 8/plate). Abundances were similar for all habitat types (88–231 individuals/quarter). Settlement plates (400 × 400 mm) were moulded with and without small ridges, along with grooves, small protrusions and pits. Plates with added habitats were concrete. Each 200 × 200 mm quarter contained either 12 serrated ridges, four-to-five grooves and ridges, 36 protrusions or 36 pits. All habitats had either regular (16 mm width, depth/height and spacing) or variable (4–28 mm) arrangement. Plates without added habitats 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”). Eight of each design were randomly arranged at both lowshore and highshore on each of two granite boulder seawalls in November–December 2009. Macroalgae on plates were counted from photographs and invertebrates in the laboratory after 13 months.

    (Summarised by: Ally Evans)

  6. Create grooves and small protrusions, ridges or ledges (1–50 mm) on intertidal artificial structures

     A replicated, randomized, controlled study in 2009–2010 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke & Todd 2016b; same experimental set-up as Loke & Todd 2016a) found that concrete settlement plates with groove habitats and small ridges, along with small protrusions and pits, supported higher macroalgae and invertebrate species richness than granite plates without added habitats, while abundances and community composition varied depending on the habitat arrangement, shore level and site. After 13 months, macroalgae and invertebrate species richness was higher on settlement plates with grooves, ridges, protrusions and pits than without at lowshore (13–23 vs 6–10 species/plate) and highshore (5–9 vs 2–3/plate). Richness was higher on plates with variable habitats than regular ones at lowshore (22–23 vs 13–16/plate), but not highshore (6–9 vs 5–6/plate). Abundances were higher on plates with added habitats than without in four of eight comparisons (9–833 vs 3–208 individuals/plate), while community composition differed in three of four comparisons (data reported as statistical model results). In all other comparisons, results were similar (abundances: 104–1,957 vs 49–1,162/plate). It is not clear whether these effects were the direct result of creating grooves and ridges, protrusions or pits. However, plate quarters with grooves and ridges had similar richness (8 species/quarter) and abundances (126 individuals/quarter) to quarters with the other habitat types (6–11 species and 88–231 individuals/quarter). Settlement plates (400 × 400 mm) were moulded with and without groove habitats and small ridges, along with small protrusions and pits. Plates with added habitats were concrete. Each 200 × 200 mm quarter contained either four-to-five concentric circular grooves and ridges, 36 protrusions, 12 ridges or 36 pits. All habitats had either regular (16 mm width, depth/height and spacing) or variable (4–28 mm) arrangement. Plates without added habitats 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”). Eight of each design were randomly arranged at both lowshore and highshore on each of two granite boulder seawalls in November–December 2009. Macroalgae on plates were counted from photographs and invertebrates in the laboratory after 13 months.

    (Summarised by: Ally Evans)

  7. Create pit habitats (1–50 mm) on intertidal artificial structures

    A replicated, randomized, controlled study in 2009–2010 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke & Todd 2016a; same experimental set-up as Loke & Todd 2016b) found that concrete settlement plates with pit habitats supported different macroalgae and invertebrate community composition with higher species richness but similar abundances compared with granite plates without pits. After 13 months, macroalgae and invertebrate species richness was higher on settlement plates with pits (11 species/plate) than without (3/plate), while abundances were statistically similar (231 vs 178 individuals/plate). Community composition differed on plates with and without pits (data reported as statistical model results). Settlement plates (200 × 200 mm) were moulded with and without pit habitats. Plates with pits were concrete with 36 square pits/plate with either regular (16 mm width, depth and spacing) or variable (4–28 mm) arrangement. Plates without 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”). Eight of each design were randomly arranged at both lowshore and highshore on each of two granite boulder seawalls in November–December 2009. Macroalgae on plates were counted from photographs and invertebrates in the laboratory after 13 months.

    (Summarised by: Ally Evans)

  8. Create pit habitats (1–50 mm) on intertidal artificial structures

    A replicated, randomized, controlled study in 2009–2010 on two intertidal seawalls on island coastlines in the Singapore Strait, Singapore (Loke & Todd 2016b; same experimental set-up as Loke & Todd 2016a) found that concrete settlement plates with pit habitats, along with grooves, small protrusions and small ridges, supported higher macroalgae and invertebrate species richness than granite plates without added habitats, but that abundances and community composition varied depending on the habitat arrangement, shore level and site. After 13 months, macroalgae and invertebrate species richness was higher on settlement plates with pits, grooves, protrusions and ridges than on plates without at lowshore (13–23 vs 6–10 species/plate) and highshore (5–9 vs 2–3/plate). Richness was higher on plates with variable habitats than regular ones at lowshore (22–23 vs 13–16/plate), but not highshore (6–9 vs 5–6/plate). Abundances were higher on plates with added habitats than without in four of eight comparisons (9–833 vs 3–208 individuals/plates), while community composition differed in three of four comparisons (data reported as statistical model results). In all other comparisons, results were similar (abundances: 104–1,957 vs 49–1,162/plate). It is not clear whether these effects were the direct result of creating pits, grooves, protrusions or ridges. However, richness was higher on plate quarters with pits (11 species/quarter) than ridges (6/quarter), but similar to quarters with protrusions and with grooves and ridges (both 8/quarter). Abundances were similar for all four habitats types (88–231 individuals/quarter). Settlement plates (400 × 400 mm) were moulded with and without pit habitats, along with grooves, small protrusions and small ridges. Plates with added habitats were concrete. Each 200 × 200 mm quarter contained either 36 square pits, four-to-five grooves and ridges, 36 protrusions or 12 ridges. All habitats had either regular (16 mm width, depth/height and spacing) or variable (4–28 mm) arrangement. Plates without added habitats 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”). Eight of each design were randomly arranged at both lowshore and highshore on each of two granite boulder seawalls in November–December 2009. Macroalgae on plates were counted from photographs and invertebrates in the laboratory after 13 months.

    (Summarised by: Ally Evans)

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