Research On The Relationship Between Density And Substrate Of 11 Kinds Of Common Seaweed In Weihai

The over-exploitation of marine living resources and environmental pollution in coastal economic development results in degradation of coastal seaweed farms and the disappearance of feeding grounds and spawning grounds for many biological resources, making fishery resources suffer severely. To curb the depletion,many fisheries developed countries effectively restores and improves the water ecological environment while promoting the sustainable development of fisheries resources by adopting artificial algal reefs. Researches have proved that algae and algal reef shape adhesion effect is closely related to each other. The more irregularities the algal reef surface has, the better for the growth of algae. But there is not enough data to show the influence of seeding density with the microstructure of surface and the different sediment is still lack of relevant data accumulation.For this reason,this study selects algae such as Rhodophyta Grateloupia asiatica,Polysiphonia urceolata,Ceramium kondoi,Rhaeophyta. Laminaria japonica,Punctaria latifolia,Desmarestia viridis,Chlorophyta Bryopsis corticulans,Urospora penicilliformis,Chaetomorpha antennina that can form a bed of macroalgae, and carries out artificial attachment and natural attachment tests in Weihai water areas with propagules algae spores.The commercially available plastic strapping belts and glass sheets were used to simulate different surface roughness of artificial algal reef. Sterile sea mud and benthic diatoms were used as different sediment to cover the surface of the artificial substrate in different hanging depth and different test period.Results are as follows:l.The experiment of artificial collecting algae adhesion density and the reef surface roughness has confirmed that the surface roughness has a significant impact on the number of attached algae spores and seedlings, roughness and density of spores and seedlings positively related.Under certain conditions,the more rough surface,there will be the more algae spores,and smooth surface absorb attached minimum of algae.2.The experiment of natural collecting algae spores shows that the number of reproductive cells without flagella(the spores of Grateloupia asiatica,Polysiphonia urceolata and Ceramium kondoi,the zygote of Bryopsis corticulans and Desmarestia viridis)which could germinate to seedling is affected by attachment roughness significantly.In certain range, both of them were positively correlated.However,the spores of Par alia sulcata,Urospora penicilliformis,Chaetomorpha antennina Kuetzing and Punctaria latifolia Grev with flagella can swim and search attachment on their own, so the density of spores has little correlation with roughness.3.The density of several seaweed is the largest with no sediment.When sediment added to the surface of attachment, different types of sediment and the different roughness of roughness have different influence on the density of algae spores.Sediment types are significant to the density of Punctaria latifolia Grev.But for the sever algae,the density is effected by there be or no attachment without experimental material.Different depth has no effect on Urospora penicilliformis and Chaetomorpha antennina Kuetzing. The density of Paralia sulcata is least at 50cm depth.The density of Polysiphonia urceolata is least when the depth at 70cm.The density of Punctaria latifolia Grev. is least when the depth at 30cm.The density of Paralia sulcata become less intense as time goes by.The density of Urospora penicilliformis and Chaetomorpha antennina Kuetzing is maximum at the second period,and the third period is more than the first period.Polysiphonia urceolata and Punctaria latifolia Grev. mainly appear in the third period, the former two are none basicly.