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Different propagation techniques for cultivationof vegetativeGigartina skottsbergiifronds were testedusing a system of suspended ropes, to which inoculantswere attached. Our results showed that triangular fragmentsobtained from the circularG. skottsbergiithalli producedharvestable frond of 800 cm2after 8 months. In contrast,inoculants of intact juvenile fronds of comparable sizeneeded at least 10 months to reach the same size. A controlexperiment with spores developing on an artificial substrateshowed that 20 months were needed to reach a surface of500 cm2, confirming the superiority of our fragment culturesystem. A pilot study demonstrated that with a density ofsix fronds m−1of farming line, the proposed system can beeconomically interesting for local fishermen.

We examined three species of diminutive Porphyra, Porphyra suborbiculata Kjellman from the North Pacific, Porphyra lilliputiana W. A. Nelson, G. A. Knight et M. W. Hawkes from the South Pacific, and Porphyra carolinensis Coll et J. Cox from the western North Atlantic. These taxa were compared in terms of morphology, habitat data and sequence haplotypes of nuclear small subunit rDNA (SSU) and internal transcribed spacers of the nuclear rDNA cistron (ITS). These three species have similar morphologies and growth habits, and share very similar type descriptions and habitat records. Haplotype variation was found within the 11 samples of P. lilliputiana we examined and within P. suborbiculata samples from two locations, but the single P. carolinensis haplotype (from collections from two separate locations) was identical to one found in several widespread P. lilliputiana samples. Unrooted phylogenetic trees based on sequence data do not support any of the three species as being a monophyletic group. We conclude that these three taxa represent a single species with the oldest name P. suborbiculata having nomenclatural priority. It is likely that P. suborbiculata has recently been introduced to the western Atlantic from the Pacific region.

The fundamental aim in fisheries management is to determine an optimal fishing effort for sustainably harvesting from a replenishable resource. The current management objective of Australia's Northern Prawn Fishery is to maximize the long-term net economic return following Australian government policy, resulting in an average recent catch of tiger prawn species of about 1,250 tons only. However, the maximum sustainable catch stated from different studies is around 3,000-4,700 tons. We also evaluated the net profit assuming that there was no buyback scheme in 2005 and the fishing fleet was kept at 89 vessels since 2005 and concluded that 40% more catch on average (2006-2009) and an additional total profit of A$17 million (excluding crew cost) could have been gained in addition to the many millions of dollars of savings in the buyback scheme. These findings have great implications for future management in Australia and elsewhere because there is a grave concern of overfishing worldwide.

Being a heat source or sink, aquifers have been used to store large quantities of thermal energy to match cooling and heating supply and demand on both a short-term and long-term basis. The current technical, economic, and environmental status of aquifer thermal energy storage (ATES) is promising. General information on the basic operation principles, design, and construction of ATES systems is discussed in this paper. Numerous projects in operation around the world are summarized to illustrate the present status of ATES. Hydrogeological-thermal simulation has become an integral part of predicting ATES system performance. Numerical models which are available to simulate an ATES system by modeling mass and heat transport in the aquifer have been summarized. This paper also presents an example of numerical simulation and thermohydraulic evaluation of a two-well, ATES system operating under a continuous flow regime.