Integrating structure-from-motion photogrammetry with geospatial software as a novel technique for quantifying 3D ecological characteristics of coral reefs.

The structural complexity of coral reefs plays a major role in the biodiversity, productivity, and overall functionality of reef ecosystems. Conventional metrics with 2-dimensional properties are inadequate for characterization of reef structural complexity. A 3-dimensional (3D) approach can better quantify topography, rugosity and other structural characteristics that play an important role in the ecology of coral reef communities. Structure-from-Motion (SfM) is an emerging low-cost photogrammetric method for high-resolution 3D topographic reconstruction. This study utilized SfM 3D reconstruction software tools to create textured mesh models of a reef at French Frigate Shoals, an atoll in the Northwestern Hawaiian Islands. The reconstructed orthophoto and digital elevation model were then integrated with geospatial software in order to quantify metrics pertaining to 3D complexity. The resulting data provided high-resolution physical properties of coral colonies that were then combined with live cover to accurately characterize the reef as a living structure. The 3D reconstruction of reef structure and complexity can be integrated with other physiological and ecological parameters in future research to develop reliable ecosystem models and improve capacity to monitor changes in the health and function of coral reef ecosystems.

Isolation and Partial Characterization of the Pink and Blue Pigments of Pocilloporid and Acroporid Corals.

The compounds responsible for the pink and blue colors of two families of hermatypic corals (Pocilloporidae, Acroporidae) from the southern Great Barrier Reef were isolated and biochemically characterized. Isolation of the pink pigment from Pocillopora damicornis (named pocilloporin, {lambda}max = 560 nm, 390 nm) revealed that it was a hydrophilic protein dimer with a native molecular weight of approximately 54 kD and subunits of 28 kD. The subunits are not linked by disulfide bonds. Attempts to dissociate the chromophore from the protein proved unsuccessful. Denaturing the protein with heat (60{deg}C) or 5% sodium dodecyl sulfate (SDS) removed the 560-nm absorbance peak without introducing a detectable bathochromic shift. In acetone, ethanol, ether, and chloroform, the pigment precipitates out of solution, leaving a colorless supernatant. These properties suggest that the protein and chromophore are covalently linked. Ion analysis revealed that the pigment does not have metal ions chelated to it. Coral pigments were also isolated from pink morphs of other pocilloporids, Seriatopora hystrix ({lambda}max = 560 nm) and Stylophora pistillata ({lambda}max = 560 nm); and from bluish regions of the acroporids, Acropora formosa (blue; {lambda}max = 590 nm) and Acropora digitifera (purple; {lambda}max = 580 nm). With the exception of A. formosa, all the corals examined had pigments with the same native (54 kD) and subunit (28 kD) molecular weights as those of P. damicornis. A. formosa pigment has a native molecular weight of about 82.6 kD and three subunits of 28 kD. The pigments isolated from each of these coral species have properties similar to those described for P. damicornis. Isolation and biochemical purification of the pigment enabled the exploration of the function of the pink pigment. Three possibilities were eliminated. The compound does not act as (i) a photoprotectant for shielding the photosynthetic pigments of symbiotic zooxanthellae against excessive irradiances, (ii) a fluorescent coupling agent for amplifying the levels of photosynthetically active radiation available for resident zooxanthellae, or (iii) a UV-screen against the high UV levels of shallow tropical marine environments.

Antiviral Substances with Systemic Effects Produced by Basidiomycetes such as Fomes fomentarius.

Inhibitors of plant virus infection with systemic effects were found in the culture filtrates of Basidiomycetes such as Fomes fomentarius and Schizophyllum commune. These inhibitors were widely distributed in Agaricales and Polyporales. The inhibitors designated as BAS (Basidiomycete Antiviral Substance) were highly active against the mechanical transmission of tobacco mosaic virus (TMV). No toxic effect was observed on the host plants. BAS-F, a polysaccharide produced by F. fomentarius, almost completely inhibited infection, when BAS-F at 2 µg/ml was applied to the same surface of leaves of Xanthi-nc tobacco 24 h before TMV inoculation to the upper surface of the leaves, and 500/0 inhibition was shown when BAS-F at 10 µg/ml was applied to the under surface of leaves. BAS-F also induced systemic resistance to the non-treated leaves when it was applied to only one leaf of the plant. BAS-F also had similar effects against the infection of TMV on bell pepper and tomato plants.