此為暫時性文件，資料尚在建立中
一般影響
早熟禾(Poa annua)被列為有害生物，對農作物有害，種子是可能的污染物(USDA-ARSU 2008)。早熟禾(Poa annua)是亞南極的先鋒物種，它率先拓殖到冰磧土(冰河碎片)留下去冰川化的土地。但是一般認為，它只是原生演替的次要角色(Frenot等人, 1998)。此外，目前尚未確定此物種是否有入侵性。Frenot等人(2001)描述此物種是歸化種，廣泛地分佈在原生社群，顯然不會導致原生社群強烈的變化。斯科特 & 柯克帕特里克(2005)測試是否有任何證據顯示早熟禾(Poa annua)可能會取代本地物種，結果並沒有發現直接證據。早熟禾(Poa annua)通常需要不斷的生物性干擾，經由踐踏提供裸露的地面，或經由授粉和動物蛻皮提供養分，成為亞南極地區的主要植被。亞南極地區人類活動的增加，可能會增加此物種的蔓延。早熟禾(Poa annua)和其他入侵物種之間的相互作用可能很大。馴鹿對亞南極島嶼的植被有重大影響，並可能助長早熟禾(Poa annua)散播(Frenot等人, 1998)。
地點特有的影響：King George Is. (Antarctic) (Antarctica) 
生態系統變化: Poa annua was noted for the first time in natural communities in summer 2005 (M. Olech Unpub. Data). However, at South Georgia and Arctowski oasis it seems to be rather persistent than invasive, and has restricted distribution in the colonisation area (M. Olech Unpub. Data, McIntosh and Walton 2000, in Chwedorzewska 2008). Macquarie Is. (sub-Antarctic) (Australia)
與其他入侵物種相互作用: The rabbits (Oryctolagus cuniculus) on Macquarie Island have caused severe vegetational damage which has allowed the further spread of Poa annua and Cerastium holosteoides (Costin & Moore 1960, in Walton 1975). Kerguelen Is. (sub-Antarctic) (French Southern Territories)
與其他入侵物種相互作用: Ten reindeer (Rangifer tarandus) from Sweden were introduced to Kerguelen in 1955 and increased to a population of circa 2000 individuals by 1972. Reindeer 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).
Sheep, rabbit and reindeer grazing has persisted for many years on Kerguelen. A recent report suggests that of the introduced plant species only P. annua, Poa pratensis, Sagina procumbens and Cerastium holosteoides seem to be taking advantage of the biotic disturbance and spreading to new areas (Young 1971, in Walton 1975).
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 (Frenot et al. 2005). Heard Is. (sub-Antarctic) (Heard Island and McDonald Islands (sub-Antarctic))
競爭: Scott & Kirkpatrick (2005) tested whether there is any indication that P. annua might displace native species. Their data set provided no direct evidence that P. annua displaces other plant species in undisturbed vegetation. Inaccessible Is. (sub-Antarctic) (Saint Helena)
生態系統變化: Nitrogen rich soils apparently favour species such as Poa annua, while adversely affecting the vigour of indigenous ferns (Huntley 1971, in Dean et al. 1994). Sth. Georgia Is. (sub-Antarctic) (Sth. Georgia and Sth. Sandwich Iss (sub-Antarctic))
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.
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