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张哲夫 《中国沙漠》1987,7(1):68-68
土壤风蚀,也称"吹扬"、"风扬"、"吹失",还被叫做风暴、黑色风暴、沙暴、焚风、艾比风、西蒙风、哈麦丹风等。风蚀的定义,广义上指风的吹蚀作用、沉积作用、搬运作用,狭义则指风的吹蚀作用、磨蚀作用、钻蚀作用、互磨作用。风的几种作用往往同时出现,其结果则取决于它们之间的力能对比关系,有时以吹蚀作用为主,有时又以沉积作用为主,搬运作用则是介于二者之间的纽带。  相似文献   
2.
Pavlova viridis sp. nov. is described on the basis of light and electron microscope observations. The material was collected from the coast of Haiyang county of Shandong, China. It is characterized by 1) yellowish green to green chloroplast, 2) rudimentary short flagellum 0. 3um long and hook-shaped, 3)long flagellum with small spherical knob-scales, 4) absence of pyrenoid and stigma, and 5) marine habitat. This new species and P . salina seem to be most closely related to each other but their colour, the insertion of their three appendages, the shape of their knob scales, and their cell periplasts are quite different from one another .  相似文献   
3.
Nephroselmis gaoae sp.nov.is described on the basis of light and electron microscope observations ofcultured material originally collected and isolated from seawater of Jiaozhou Bay,Qingdao,China.Theperiplasts on the cell body and flagella are covered by five types of scales,two types on the flagella andthree on the body.Among these,the morphology and the number of spines of large stellate body scalesdiffer remarkably from those of previously described species of Nephroselmis.Apart from these,the unusualfine structure of the eyespot(stigma)is very characteristic.As in the other species of Nephroselmis,theeyespot lies immediately under the two-membraned chloroplast envelope;unlike the others,however,it isnot composed of a number of osmiophilic globules,but consists of about 14 curved rod-shapedosmiophilic bodies arranged loosely and randomly.This feature distinguishes the present new species notonly from the other species of Nephroselmis but also from the other motile algal species,the eyespots struc-ture  相似文献   
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