| dc.description.abstract | Hard-substrate organisms such as oysters and barnacles reduce coastal erosion, improve water quality, and promote biodiversity. However, hard-substrate communities are threatened by dredging, sedimentation, invasive species, and coastal development. Engineered structures such as pilings, bulkheads, and seawalls simplify the environment and change the composition of available substrates. Because of these differences, engineered structures often do not support the same community as the unmodified environment. By building marine structures from materials that enhance settlement, it may be possible to mitigate their impact and use marine engineering for environmental restoration. Panels made from five common marine engineering materials, wood, steel, PVC, and two different cement mixes, one containing fly ash and silica fume (CM1), the other containing ground granulated blast furnace slag (CM2), were deployed in Galveston Bay. Invertebrate colonization was monitored for three months, and resulting communities were compared at the end of deployment. CM1 panels had significantly greater cover than steel early in the observation period, and all CM1 panels had live cover ≥95% at the end of deployment. CM1 panels had significantly greater richness than wood and were significantly more diverse than CM2 panels. Furthermore, the materials appeared to form unique and different communities. These results demonstrate that hard substrate organisms show a settling preference for different construction materials. It may be advisable for marine engineering structures in Galveston Bay to be made using cement mixtures similar to CM1 to promote the biodiversity of hard-substrate organisms. | |
