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此物種詳細資訊 Sth. Georgia Is. (sub-Antarctic) 狀態： 外來
入侵：
出現紀錄： ?????
來源： Walton 1975 此地點的物種說明：
Poa annua occurs near most of the beaches previously important for sealing, and around all the whaling stations. This species was collected on South Georgia in 1902 before the establishment of any whaling stations and Walton & Smith (1973) speculate that P. annua was probably subject to multiple introductions during the 19th century by sealers (Walton 1975).
The most successful member of the alien flora, P. annua (Longton 1965, in Longton 1966), is widely distributed on South Georgia; although five others (Cerastium fontanum, Rumex acetosella, Taraxacum officinale, Deschampsia caespitosa and
Poa pratensis) grow up to at least 1 km from former whaling stations (McIntosh & Walton 2000, in Frenot et al. 2005). P. annua, C. fontanum and T. officinale, have spread from the vicinity of the whaling stations. P. annua may form closed lawns in heavily grazed stands (Moen & MacAlister 1994). P. annua is a persistent naturalised alien existing as a perennial; it is close cropped but exceptionally tolerant of grazing and trampling (Pratt & Smith 1982). 影響：
生態系統變化: Poa annua has formed replacement swards (see Kightley and Smith 1976) where some native species have been eradicated.
與其他入侵物種相互作用: Reindeer (Rangifer tarandus) have major impacts on the vegetation of the sub-Antarctic Islands and may encourage the dispersal and establishment of the more resilient invasive grass, Poa annua (Frenot et al. 2005).
Distribution of P. annua, Cerastium fontanum and Taraxacum officinale may have been assisted by reindeer through seed transport in droppings and on hair and hooves (Moen & MacAlister 1994). P. annua is heavily grazed by reindeer, especially mid-late summer (February to March) (Pratt & Smith 1982).
降低本地生物多樣性: If climate changes continue, with increases in temperatures and decreases in rainfall, the spread of P. annua is predicted to increase with negative consequences for indigenous plant communities. 最後修改 ： 26/03/2009 3:07:19 p.m.
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