| Soil seed bank is summation of vigor seed both in soil and on its surface. Effect of seed banks on populations of species and persistence of communities are important. The research on soil seed banks is an important subject in plant ecology. It has a plenty of study about Soil Seed Bank of Picea schrenkiana, but actually Soil Seed Bank of Picea schrenkiana has experienced after the seed age and Soil Seed Bank of Picea schrenkiana has any to be different, so continued the same sampling spot , the sampling depth and the sampling time for this in this research. In this study bourgeon method is adopted to observe the soil seed bank of Picea schrenkiana Fish.et Mey. forest in tianshan mountain from altitude 1800 to 2200 meters , and niche, specie diversity and biology statistics are also used. The conclusion shows as follows:①The density of soil seed bank is 922.00±662.21ind/m2 in spring and is 780.75±472.21ind/m2 in autumn after the seed age. Among, the amount of seed gets 63.39% and 72.78% in all. In contrast of soil seed bank, the density of soil seed bank is decrease, but the amount of seed of Picea schrenkiana Forest is not change.②As for the soil seed bank vertical spatial distribution after seed age, neighter in spring nor in autumn , indicates that the viable seed density in soil seed bank decreased with the increasing of soil depth. The amount of seed in soil depth of 0～2cm is best of all in the five differents of soil depth. As far as soil seed bank in depth of 0～10cm, about above 85% of seed distribute forest flooring and surface layer soil form ground in soil depth of 6cm.③The common species index between soil seed bank and aboveground vegetation is about 16, except one kind.here are mainly and perennial plants which is composed of Aegopodium alpestre Ldb.,Poasupina Schrad,Stellaria soongorica Roshev.,Cicerbita azurea (Ldb.) Beauv.and Erigeron acer L.,in species makeup of soil seed bank except for the P. schrenkiana Fish.et Mey. Study on species diversity shows that species diversity index of soil seed bank in fenced fields is more higher diversity than in unfenced fields.④After the niche study on dominant species in soil seed bank of P. schrenkiana Fish.et Mey.forest, the result shows that :The niche breadth of Poa supina Schrad. is the most wide in the soil seed bank, reaching to 4.6804; and Galium boreale L.is the most narrow. only 1.6. In different kind to between, the highest niche overlap is between Stellaria soongorica Roshev. and Picea schrenkiana Fish.et Mey., getting to 0.9908, and the lowest between Equisetum arvense L. and Picea schrenkiana Fish.et Mey., only getting to 1.6.⑤Through the survey of the aboveground vegetation, the aboveground vegetation is mainly composed of Pinaceae, Umbellifera, Iridaceae, Compositae and Graminae, occupying 44.44%, 21.25%, 9.78%, 7.21%, 6.52%, respectively and the total seedlings occupies always 89.2%. The similarity between soil seed bank and aboveground vegetation ranges from 0.313 to 0.5. There is low similarity between soil seed bank and aboveground vegetation in fenced fields, but the aboveground vegetation is more higher diversity than the soil bank. The similarity between soil seed bank and aboveground vegetation in unfenced fields is little high than in fenced fields, because of less species. Moreover, the conclution of similarity about the aboveground vegetation and the soil seed bank is basic consistent after the seed age and before the seed age.⑥Through the seed disintegration experiment in nature, the results show that seed vitality of P. schrenkiana Fish.et Mey. decline from 74.5% to 37.58% in half a year. The percentage gets to 6.09% after one year and to 4.67% after half and one year. The vitality shows a sharp decrease, and it is no difference to vitality in different soil layers.
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