摘要: Presence of pollen in the atmosphere was determined inTartu 1989–1997, Kuressaare 1996–1997 and inSiauliai 1997. Ragweed airpollen found latesummer three years. The distribution, abundance andflowering local ragweed plants were estimated. Itappeared that number sources did notexceed twenty per country year. Majority thesesources consisted a small pollinating A. artemisiifolia individuals. largest localsources, consisting several hundreds ofindividuals, exclusively rare. Transport ofragweed by air masses from distant wasstudied. It incursions ragweedpollen fluxes originating fromthe Ukraine as well southeastern andsouthern regions European part Russia. Theseincursions occurred extensive high-pressure areaswhose centre located central region theEuropean Russia with periphery extending tothe Baltic countries.
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sci-hub.se 参考文章(3)
Z. Gudžinskas, Genus Ambrosia L. (Asteraceae) in Lithuania. Thaiszia. ,vol. 3, pp. 89- 96 ,(1993)
O. V. Kovalev, Spread of adventitious plants of the tribe Ambrosia in Eurasia and methods of biological control of weeds of the genus Ambrosia L. (Ambrosieae, Asteraceae). Trudy Zoologicheskii, Institut Akademii Nauk SSSR. ,vol. 189, pp. 7- 23 ,(1989)
Magda Járai-Komlódi, Miklós Juhász, Ambrosia elatior (L.) in Hungary (1989–1990) Aerobiologia. ,vol. 9, pp. 75- 78 ,(1993) , 10.1007/BF02311373