Restoration potential of seagrass Posidonia australis Hook f. seedlings is enhanced through aquaculture

    Research output: ThesisDoctoral Thesis

    313 Downloads (Pure)

    Abstract

    [Truncated abstract] Seeds are potentially an ecologically sustainable source of planting units for restoring seagrasses. However, seeds of the temperate Australian seagrass Posidonia australis Hook. f. germinate before shedding (vivipary), and this lack of dormancy means that seeds cannot be banked for later use in restoration. To extend the timeline for seed-based restoration, this study investigated conditions for culturing seedlings in land-based aquaculture facilities, examining approaches to preconditioning seedlings with the aim of optimizing their vigour before transplanting into the field. Growth conditions in culture were tested in four separate experiments. In addition, a series of pilot-scale studies investigated strategies to establish seedlings in the field. Growth responses were examined firstly for three sediment types (unsorted carbonate, unsorted silicate and well-sorted silicate), with and without addition of organic matter. Seedling leaf, root, rhizome and total biomass increased when organic matter was added to unsorted carbonate and unsorted silicate sediment but not well-sorted silicate sediment. Root length and number of lateral root branches was also greatest in unsorted sediments, and when organic matter was added. A second component examined whether growth of seedlings could be enhanced by adding inorganic nutrients to the sediment. Sediments were supplemented with inorganic nitrogen (N) and phosphorus (P) in a factorial design (no nutrient addition, +N, +P, +N+P). Growth of seedlings was not enhanced by addition of N or P to the sediment despite nutrient uptake. Leaf mass, leaf area and leaf production were unchanged by nutrient additions whereas the size of the seedling root system, in terms of biomass, length and the density of lateral root branches was significantly reduced...
    Original languageEnglish
    QualificationDoctor of Philosophy
    Publication statusUnpublished - 2011

    Fingerprint

    Dive into the research topics of 'Restoration potential of seagrass Posidonia australis Hook f. seedlings is enhanced through aquaculture'. Together they form a unique fingerprint.

    Cite this