Recent Years, Frequent Storm Surge Disasters Caused by Abnormal Changes in Global Climate, Huge Disaster Losses to China. Scientific estimation of risk value of storm surge disaster, is of great significance for measuring storm surge disaster risk, estimation of storm surge disaster loss, guiding effective dispersion of disaster risk. In view of the distinct characteristics of low frequency and thick tail of storm surge disaster loss data in China, POT model based on extreme value theory is introduced to complete the fitting of direct economic loss distribution of storm surge disaster, calculate the risk value under different confidence levels, and pass the Kupiec failure frequency test.

Research shows that uses POT model to calculate the risk value under different confidence levels can be used as the basis for scientific measurement of storm surge disaster risk and reasonable estimation of the maximum possible loss of a single disaster.

In this paper, a method for the determination of 14 rare earth elements in seawater by inductively coupled plasma mass spectrometry was established through optimization of conditions, standard verification, etc. adding NH3·H2O solution directly into seawater to form coprecipitation, enrichment and separation of rare earth elements and magnesium hydroxide. After co-precipitation and centrifugation of seawater samples, the main matrix substances were separated and the target rare earth elements were enriched. The conditions for co-precipitation and enrichment of magnesium hydroxide are as follows: the optimum addition amount of 1 : 1 NH 3 H 2O solution is 0. 35mL, precipitation cleaning times for 1 time, standing time for 5min. Methods The standard addition recovery rate of rare earth elements was 88. 7%-107. 1%, the method blank of rare earth element is 0. 008×10－12-0. 441× 10-12, the lower limit of quantification is 0. 054×10－12-0. 423×10-12 with RSD of 2. 8%-8. 6%. The established method is consistent with the determination results of seawater standard substance NASS-6. The method has the advantages of high accuracy and precision, simple and rapid operation, and can be used for quantitative and accurate determination of rare earth elements in large quantities of seawater samples.

The existence of trace metals in seawater determines their biotoxicity and availability, and directly affects their migration and fate, thus attracting much attention . However, the seawater matrix is complex , trace metal concentration is extremely low, sampling and analysis process is easy to introduce pollution, so the research on trace metal and its existing forms in seawater requires high sampling and test analysis technology . Among many morphological analysis methods, stripping voltammetry combines effective enrichment methods with advanced measurement techniques, has the advantages of high sensitivity, , good selectivity, etc., and is currently widely used .  Internationally, stripping voltammetry for speciation analysis of trace metals has been continuously updated and developed, but at present, the research in this field in China is still relatively scarce, whether in the offshore or the ocean, . This article will introduce the existing forms and latest research progress of several trace metals (Cu, Pb, Zn , CD) in seawater by stripping voltammetry in the world at present, so as to promote the understanding and development of marine science in our country .

With the rapid development of China's mariculture industry, the discharge amount of aquaculture tail water is increasing day by day, which has exceeded the discharge amount of land-sourced sewage into the sea and brought serious marine environmental problems. Therefore, it is very important to repair the aquaculture tail water. This paper introduces the research status of halophyte in the remediation of seawater aquaculture tail water, summarizes its remediation capability and mechanism, summarizes the problems that halophyte should pay attention to in the purification of seawater aquaculture tail water, and looks forward to the development prospect of this purification technology.