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A B S T R A C TSample preparation is a crucial bottleneck in the whole analytical process. Solid-phase sorbents (SPSs) have aroused increasing interest in research on sample preparation, as they have key roles in obtaining high clean-up and enrichment efficiency in the analysis of trace targets present in complex matrices. The objective of this review is to provide a broad overview of the recent advances and applications of SPSs in sample preparation prior to chromatographic analysis, during the period 2008-13. We include SPSs, such as molecularly-imprinted polymers, carbon nanomaterials, metallic nanoparticles and metal organic frameworks, focusing on solid-phase extraction, solid-phase microextraction, matrix solid-phase dispersion and stir-bar sorptive extraction of typical pollutants in environmental, biological, food and pharmaceutical samples. We propose remaining challenges and future perspectives to improve development of new SPSs and to apply them further.

To discover the original source and clarify development of the world's largest transregional green tides in the Yellow Sea, an integrated investigation covering the Subei Shoal coastal waters and the adjacent regions was carried out during March to June of 2012. The results showed that macroalgal wastes from the connecting ropes of Porphyra aquaculture rafts contributed significantly to the original biomass of free-floating green algae. Approximately 6500 t of Ulva prolifera were released into the coastal waters from mid-April to late-May when farmers were cleaning aquaculture facilities. Among the total biomass disposed, about 62.3% floated up to the sea surface, which turned into the original floating patches. The floating U. prolifera, with a high growth rate of 26.3% per day, dominated in the floating algal patches rapidly, moved northward under the hydrodynamic action, and formed a massive free-floating green tide near the south of Shandong peninsula in early June. The optimal sea temperature and sufficient nutrients in the Yellow Sea facilitated the formation of the green tide. No other source contributing substantially to the initial floating biomass was detected in the survey except those from the connecting ropes of rafts. Based on our field data, we concluded that the green tide in Yellow Sea is a transregional disaster stimulated directly by the unhygienic husbandry and maintenance practices of coastal aquaculture.

Sea cucumber aquaculture has flourished as a result of increasing demand coupled with declining wild fisheries and has been facilitated by technical progress in the production and grow-out phase of larvae and small juvenile sea cucumbers. China has developed a large and successful sea cucumber aquaculture industry based on the temperate species Apostichopus japonicus (Selenka, 1867). China consumes most of its domestic sea cucumber production (193, 705 tons: 2013), exporting only a few dozen tons. Much of the success of sea cucumber aquaculture in China came from advances in culture methods, especially for the early stages of broodstock conditioning, larval production and settlement, and the critical early juvenile development stage. These artificial approaches to production are a precondition for all aquaculture models, and the scientific procedures and management protocols must be strictly adhered to for success. Similarly, the growout phase of sea cucumber production in China has evolved from attempts using disused fish and shrimp ponds to new, dedicated ponds developed to meet the more sensitive requirements of sea cucumbers for water quality and substrate type and to the use of ocean ranching. Various diseases have affected this industry and become barriers to its sustainable development. To achieve higher survival rates and better production quality, the trend has been toward ocean ranching of sea cucumbers and stock enhancement, and production levels have increased significantly in recent years. While cost-effective methods for sea cucumber aquaculture close to their point of consumption is good news for wild stocks of sea cucumbers in different parts of the world, there is a potential downside in the environmental impact of such extensive production methods. The influence of sea cucumber aquaculture on the environment and the influence of the environment on sea cucumber aquaculture are important issues relating to ecological security and sustainability.

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The Pseudomonas putida strain SP1 was isolated from marine environment and was found to be resistant to 280 μM HgCl 2 . SP1 was also highly resistant to other metals, including CdCl 2 , CoCl 2 , CrCl 3 , CuCl 2 , PbCl 2 , and ZnSO 4 , and the antibiotics ampicillin (Ap), kanamycin (Kn), chloramphenicol (Cm), and tetracycline (Tc). mer operon, possessed by most mercury-resistant bacteria, and other diverse types of resistant determinants were all located on the bacterial chromosome. Cold vapor atomic absorption spectrometry and a volatilization test indicated that the isolated P. putida SP1 was able to volatilize almost 100% of the total mercury it was exposed to and could potentially be used for bioremediation in marine environments. The optimal pH for the growth of P. putida SP1 in the presence of HgCl 2 and the removal of HgCl 2 by P. putida SP1 was between 8.0 and 9.0, whereas the optimal pH for the expression of merA, the mercuric reductase enzyme in mer operon that reduces reactive Hg 2+ to volatile and relatively inert monoatomic Hg 0 vapor, was around 5.0. LD 50 of P. putida SP1 to flounder and turbot was 1.5× 10 9 CFU. Biofilm developed by P. putida SP1 was 1-to 3-fold lower than biofilm developed by an aquatic pathogen Pseudomonas fluorescens TSS. The results of this study indicate that P. putida SP1 is a low virulence strain that can potentially be applied in the bioremediation of HgCl 2 contamination over a broad range of pH.

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