| The author mainly investigate the seagrass species in inshore areas of Shandong province and resource and ecological environment of seagrass bed, and study the morphology, reproducing biology, and life history of eelgrass(Zostera marina L.) and restoration of injured Z. marina Biome in a representative sea area. The most results are summarized as follows:Preliminary survey for seagrass species was performed in inshore areas of Shandong province in July 2008. In the meantime, morphological characteristics of seagrasses distributing in inshore areas of Shandong province were described. Also, status and degeneration causes of seagrass resources in inshore areas of Shandong province were analyzed. Four species of seagrasses including Zostera marina L. Zostera caespitosa Miki, Phyllospadix iwatensis Makino and Phyllospadix japonicus were found during the present investigation.The distribution, biomass, morphology, seed and habitat of eelgrass(Zostera marina L.) within the water depth of 2 m were surveyed in the inshore areas of Lidao Town of Rongcheng City (between Mata Jiao and "Waizhe Dao"of Lidao Bay) in June 2008. Eelgrasses in the survey areas show a patch-shape distribution and the area of each patch is between 1.5 and 2.0 m2. The average spacing density and biomass of eelgrass are 1650 ind/m2 and 3.754 g/ind, respectively. The root length range is 2-14 cm and the average root weight, root length, and root diameter are 0.4324 g/ind, 4.8295 cm and 0.1 mm, respectively. The average rhizome weight, rhizome length and rhizome diameter are 0.4609 g/ind,4.407 cm/ind and 2.159 mm, respectively. The average number of nodes and node length are 9.27 nodes/ind and 5.144 mm, respectively. The leaf length range is 17-70 cm and the average leaf weight, leaf width, leaf length and sheath length are 2.294 g/ind,5.28 cm,45.23 cm and 6.824 cm, respectively.The flower of eelgrass is monosexual and hermaphrodite. There are two female flowers between two male flowers. The numbers of male flowers and female flowers on each rachis are 13-19 and 7-11, respectively. The sediment under the eelgrass consists of gravel sand.The morphological characteristics (root length, node length, leaf length and leaf width) of eelgrass (Z. marina L.) were monthly surveyed in the Swan Lake of Rongcheng City, Shandong province from February 2009 to January 2010. The formation of reproductive shoots and growth of seeds are also sampled duiring March and August in 2009. The results show that the root length range of eelgrasses in the survey areas is 0.4 cm～17.4 cm, the fresh weight and dry weight are 0.01 g～2,47 g,0.01 g～0.55g, respectively. The node length range is 0.07 cm～7.1 cm, the node diameter range is 0.07 cm～1.19 cm, and the fresh weight and the dry weigt range of rhizome are 0.01 g～4.57 g and 0.01 g～0.88 g, respectively. The leaf length and width range are 0.28 cm～98.3 cm and 0.1 cm～0.96 cm, respectively. The sheath length range is 0.2 cm～28.5 cm. The fresh weight and dry weigh range of leaf are 0.09 g～0.9 g and 0.01 g～2.68 g, respectively. The maximum of morphological characteristics are observed in July and the minimum are observed from January to March. The reproductive shoot range of eelgrasses is 29.5 cm～111.4 cm. The leaf length and width range of reproductive shoot are 6.5 cm～49.2 cm and 0.18 cm～0.62 cm, respectively. The rachis length range of reproductive shoot is 3.5 cm～19.6 cm. The fresh weight and dry weigt range of seeds are 0.0042 g～0.0096 g and 0.002 g～0.009 g, respectively. The length and width range of seed are 1.9 mm～3.5 mm and 0.7 mm～1.0 mm, respectively. The growth charicteristic of eelgrasses in Swan Lake is allometric growth.The inflow river, sediment, ecological environment (quarterly) and resource (monthly) of seagrass meadow in Swan Lake are investigated from February 2009 to January 2010. The results show that there is 5 inflow river for Swan Lake, which is all polluted; the sediment of the eelgrass meadow consists of sandy silt and silty sand; the DO of the surface seawater in Swan Lake is conformed to the standard of 1st class seawater, BOD, COD and pH are conformed to the standard of 2nd class seawater, and ammonia-nitrogen and active phosphate are conformed to the standard of 4th seawater; 55 species of plankton are found in the four quartly survey, in which 33 species are phytoplankton and 22 species are zooplankton; The most species and the highest abundance of plankton are found in November, and these show a tendy to increasing from spring to winter; 31 species of Dilong net, including 22 species of Fishes,5 species of Crustacean,2 species of Mollusca and 1 specie of Echinoderms, are found, and the population fluctuation changed obviously with season.To find feasible method of transplant and restoration for eelgrass Zostera marina, eelgrass was transplanted using methods of rock planting, stapling, free planting, root gripping and box planting in the inshore areas of Lidao Town of Rongcheng City from October to November in 2008. Growth, survival and osmotic pressure of transplanting eelgrass were investigated after one month of transplanting. Difference between nature and transplanting eelgrass was compared. The relationship between growth and survival of transplanting eelgrass and primary environmental factors was analyzed. Results in the present study showed that survival rate of transplanting eelgrass was followed as rock planting (100%)>stapling (86.7%)>free planting (66.7%)>root gripping (20%)>box planting (0%).The growth of transplanting eelgrass was followed as rock planting (0.358 cm·d-1)>free planting (0.242 cm·d-1)>control (0.211 cm·d-1)>stapling (0.083 cm·d-1)>root gripping (0.067 cm·d-1). Osmotic pressure of roots in transplanting eelgrass was significantly higher than that in nature eelgrass, however, rhizomes and leaves showed opposite changes (P<0.01). There was a remarkable correlation between growth and survival of transplanting eelgrass and primary environmental factors. The findings will provide data for developing feasible and low-costing transplant and restoration technology of injured Z.marina biome.Eelgrass is monthly sampled and then is transplanted using the method of stapling in Swan lake. Survival rate and morphological charactericstics of transplanting eelgrass are monthly surveyed. The environmental factors that influence survival of eelgrass are also analyzed. Results indicate that transplanting eelgrass show a good growth and the average survival rate is 88%. It could be obtained through various factors that:the order of the best time for eelgrass transplanting in Swan Lake is followed as July> August> September> October> November.
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