Neda Mehdipour received her PhD degree in Marine Biology from the University of Science and Technology (Tehran). She is an Assistant Professor at the Iranian National Institute for Oceanography and Atmospheric Science and an invited Lecturer at the University of Mazandaran. Her research interests lie in the area of marine ecology and marine biology. She has conducted several research projects in the fields of algae ecology and biotechnology.
Laurencia caspica, a marine macroalga species were analyzed to determine its proximate chemical composition. The investigated species demonstrated high carbohydrate (25.5±0.20 % dry wt.) protein (22.22±0.4 % dry wt.), Ash (26.82±0.31 % dry wt.) and moisture components (12.00±0.23 % dry wt.) and low lipid content (0.03±0.05 % dry wt.). Glutamic acid (192.24±1.4 mg 100g-1 dry wt.) and Aspartic acid (160.77±1.1 mg 100g-1 dry wt.) were the most abundant free amino acids, while Histidine (21.15±0.1 mg 100g-1 dry wt.) and Glycine (29.99±0.3 mg 100g-1 dry wt.) contents were the lowest in the free amino-acid profiles. All essential amino acids were detected in the species tested. Unsaturated fatty acid constituted about 64% of total fatty acids, mainly 8-Octadecenoic acid and saturated fatty acids represented 36% of the total fatty acids (mainly myristic acid). This study was conducted to create a nutritional data for Laurencia caspica in order to popularize its consumption and utilization in the southern coasts of the Caspian Sea.
Maarten de Jong is a marine ecologist and is currently finishing his PhD project “Modelling the ecological potential of sand extraction”. The project is a part of the Dutch EcoShape/Building with Nature program and focuses on the short-term impacts of large-scale and deep sand extraction and ecological landscaping on organisms onthe seabed, bottom fish and the change of sediment characteristics, bathymetry and hydrodynamics. He is a member of Working Group on the Effects of Extraction of Marine Sediments on the Marine Ecosystem (WGEXT) of the International Council for the Exploration of the Sea (ICES). He has published papers high-ranking scientific journals and others are on the verge of publication. He is now looking for postdoc or consultancy functions in the field of ecology and hydrodynamics in all climate regions.
The demand for marine sand in the Netherlands and globally is still increasing. The Dutch authorities promote sand extraction depths deeper than 2 m for volumes over 10 million m3 of sand, to maintain sufficient supply and to decrease the surface area of impact. The ecological effects of deep sand extraction, however, are still largely unknown. Therefore, we investigated short-term effects of deep sand extraction (20 – 24 m) and compared these with other case studies such as, common shallow sand extraction on the Dutch Continental Shelf (2 m) and an 8 m deepened shipping lane. For intercomparison between case studies we applied the tide-averaged bed shear stress as a generic proxy for changed environmental conditions and related ecological effects. Bed shear stress can be estimated using a two-dimensional quadratic friction law or a three-dimensional hydrodynamic model. We developed ecosystem-based design rules based on two-dimensional tide-averaged bed shear stress values and ecological data.rnTide-averaged bed shear stress showed an asymptotical decrease from 0.50 to 0.04 N m-2 in borrow pits in 20 m deep water and extraction depths up to 24 m. Borrow pits with decreases in tide-averaged bed shear stress of smaller than 0.17 N m-2 may lead to enhanced macrozoobenthic species richness and biomass. Below tide-averaged bed shear stresses of 0.08 N m-2, increasing abundance of brittle stars and below 0.08 N m-2 detrimental effects can be expected. In general, at higher depth-averaged flow velocity magnitudes and initial water depth, higher extraction depths can be applied to facilitate tide-averaged bed shear stresses of the case studies and related ecological response. The ecosystem-based design rules can be used in the early-design phases of future borrow pits in the southern North Sea but 3-D approaches are recommended in later-design phases to achieve more accurate shear stress values for more realistic designs.rn