Aquaculture Perspective of Multi-Use Sites in the Open Ocean: The Untapped Potential for Marine Resources in the Anthropocene

This volume addresses the potential for combining large-scale marine aquaculture of macroalgae, molluscs, crustaceans, and finfish, with offshore structures, primarily those associated with energy production, such as wind turbines and oil-drilling platforms. The volume offers a comprehensive overview and includes chapters on policy, science, engineering, and economic aspects to make this concept a reality. The compilation of chapters authored by internationally recognized researchers across the globe addresses the theoretical and practical aspects of multi-use, and presents case studies of research, development, and demonstration-scale installations in the US and EU

Neodymium isotope constraints on provenance, dispersal, and climate-driven supply of Zambezi sediments along the Mozambique Margin during the past ∼45,000 years

Marine sediments deposited off the Zambezi River that drains a considerable part of the southeast African continent provide continuous records of the continental climatic and environmental conditions. Here we present time series of neodymium (Nd) isotope signatures of the detrital sediment fraction during the past ~45,000 years, to reconstruct climate-driven changes in the provenance of clays deposited along the Mozambique Margin. Coherent with the surface current regime, the Nd isotope distribution in surface sediments reveals mixing of the alongshore flowing Zambezi suspension load with sediments supplied by smaller rivers located further north. To reconstruct past changes in sediment provenances, Nd isotope signatures of clays that are not significantly fractionated during weathering processes have been obtained from core 64PE304-80, which was recovered just north of the Zambezi mouth at 1329 m water depth. Distinctly unradiogenic clay signatures (ENd values <214.2) are found during the Last Glacial Maximum, Heinrich Stadial 1, and Younger Dryas. In contrast, the Nd isotope record shows higher, more radiogenic isotope signatures during Marine Isotope Stage 3 and between ~15 and ~5 ka BP, the latter coinciding with the timing of the northern hemisphere African Humid Period. The clay-sized sediment fraction with the least radiogenic Nd isotope signatures was deposited during the Holocene, when the adjacent Mozambique Shelf became completely flooded. In general, the contribution of the distinctly unradiogenic Zambezi suspension load has followed the intensity of precession-forced monsoonal precipitation and enhanced during periods of increased southern hemisphere insolation and high-latitude northern hemispheric climate variability

CMS physics technical design report : Addendum on high density QCD with heavy ions

Peer reviewe

Simulation of the effects of grain boundary fission gas during thermal transients

This report presents the results of an initial set of out-of-cell transient heating experiments performed on unirradiated UO/sub 2/ pellets fabricated to simulate the effect of grain boundary fission gas on fuel swelling and cladding failure. The fabrication involved trapping high-pressure argon on internal pores by sintering annular UO/sub 2/ pellets in a hot isostatic press (HIP). The pellet stack was subjected to two separate transients (DGF83-03A and -03B). Figures show photomicrographs of HIPped and non-HIPped UO/sub 2/, respectively, and the adjacent cladding after DGF83-03B. Fuel melting occurred at the center of both the HIPped and non-HIPped pellets; however, a dark ring is present near the center in the HIPped fuel but not in the non-HIPped fuel. This dark band is a high-porosity region due to increased grain boundary/edge swelling in that pellet. In contrast, grain boundary/edge swelling did not occur in the non-HIPped pellets. Thus, the presence of the high-pressure argon trapped on internal pores during sintering in the HIP altered the microstructural behavior. Results of these preliminary tests indicate that the microstructural behavior of HIPped fuel during thermal transients is different from the behavior of conventionally fabricated fuel

Response of young bearing olive trees to irrigation-induced salinity

<p>Expansion of irrigated olives, combined with prevalence of water containing dissolved salts, leads to irrigation-induced exposure of olive trees to salinity. Root zone salinity can rise either as a function of increasing input irrigation water salinity (ECi) or relative reductions in water for leaching. We investigated five ECi levels from 0.5 to 11.0 dS m⁻¹ with a constant leaching fraction (LF) of 0.29 and five leaching levels from 0.05 to 0.44 (drainage: irrigation ratio) with water of ECi = 5.0 dS m⁻¹ on young bearing Olea europaea cv Barnea olive trees grown in 2.5 m³ weighing-drainage lysimeters over three years. Tree-scale response to increased salinity did not demonstrate any sign of a threshold value and was not differentiated by the cause of salinity, be it changes in input irrigation water salt concentrations or changes in LF. Soil salinity, measured as electrical conductivity of saturated soil paste extract (ECe) and maintained at stable levels over time, decreased tree water consumption and tree size measured as trunk area or above-ground biomass by 40–60 % as it increased from 1.2 to around 3.5–4.0 dS m⁻¹. Further increases in ECe to as high as 7.5 dS m⁻¹ brought these parameters to 20–30 % of the treatment with low salinity. Fruit yield also decreased with increasing salinity, albeit with less drastic relative effects. An analytical model calculating water and salt balance and subsequent evapotranspiration or biomass as a function of irrigation water quantity and salinity successfully predicted the measured results.</p

Response of young bearing olive trees to irrigation-induced salinity

Expansion of irrigated olives, combined with prevalence of water containing dissolved salts, leads to irrigation-induced exposure of olive trees to salinity. Root zone salinity can rise either as a function of increasing input irrigation water salinity (ECi) or relative reductions in water for leaching. We investigated five ECi levels from 0.5 to 11.0 dS m−1 with a constant leaching fraction (LF) of 0.29 and five leaching levels from 0.05 to 0.44 (drainage: irrigation ratio) with water of ECi = 5.0 dS m−1 on young bearing Olea europaea cv Barnea olive trees grown in 2.5 m3 weighing-drainage lysimeters over three years. Tree-scale response to increased salinity did not demonstrate any sign of a threshold value and was not differentiated by the cause of salinity, be it changes in input irrigation water salt concentrations or changes in LF. Soil salinity, measured as electrical conductivity of saturated soil paste extract (ECe) and maintained at stable levels over time, decreased tree water consumption and tree size measured as trunk area or above-ground biomass by 40–60 % as it increased from 1.2 to around 3.5–4.0 dS m−1. Further increases in ECe to as high as 7.5 dS m−1 brought these parameters to 20–30 % of the treatment with low salinity. Fruit yield also decreased with increasing salinity, albeit with less drastic relative effects. An analytical model calculating water and salt balance and subsequent evapotranspiration or biomass as a function of irrigation water quantity and salinity successfully predicted the measured results.</p