Alternanthera philoxeroides (水生植物, 草本植物)

生态 分布 管理 影响 参考数据 联系

一般影响 Gunasekera(1999)报告说：空心莲子草被认为是一个世界上最严重的水生杂草。此植物的水生型有可能严重威胁水路、农业和环境。陆地型会形成一个密集植垫，具有庞大的地下根茎和根系。其遮荫会窒息大多数其它草本植物。白金汉(1996)报告说：浮动的茎生长在整个水面形成致密交织的植垫。此植垫堵塞了航道，竞逐沿岸的原生植物。英联邦澳大利亚(2000)报告说：空心莲子草笼罩在水面上，会破坏水域环境，阻碍光线渗透及气体交换(有时导致厌氧)对植物和动物产生不利影响。植垫会阻碍水流，卡在结构物上，因而促进沉积和洪水。它们会阻碍获取和利用水资源，提供蚊子栖息地，产生健康问题，影响自然景观。在它已经建立族群的地方，控制此物种已被证明是一个昂贵和复杂的考验。          地点特有的影响： Australia   滋扰人类: Alligator weed may prevent access to water bodies in Australia, thereby disrupting various recreational activities as well as potentially threatening livelihoods and industries dependent on clear waterways. For example, Liverpool City Council spent $8,000 annually to reduce the visual impact of alligator weed and to maintain a section of the river available for use by a rowing club. Alligator weed may cause health problems in Australia by providing habitats for mosquitoes. 生态系统变化: In Australia, alligator weed disrupts natural aquatic ecosystems by blanketing the surface of the water with thick mats and impeding penetration of light to the ground. Mats promote sedimentation and flooding and prevent gaseous exchange (which may lead to anaerobic conditions). Flow-down affects of these significant ecosystem changes (on native flora and fauna) are certain. 经济 /民生: In Australia, alligator weed may invade important agricultural systems such as irrigation areas and significantly reduce production. In New Zealand and Australia it also has the potential to cause photosynthesisation of the skin in cattle, resulting in cancerous lesions. When the Barren Box Swamp (NSW) infestation was found in 1994, it was estimated that the potential costs to the irrigation farming community could be as high as $250 million per year. An annual control programme would have cost $6 to $8 per mega L of water at the farm gate, an increase of 30% delivery cost. Hence an eradication programme of this relatively small infestation was undertaken, costing more than $3 million to date and continuing. In the Hawkesbury/Nepean catchment the weed threatens the $35 million per year turf industry and the $50 million per year vegetable industry, as well as recreational use and in-stream extraction. Hunter Valley (Australia)   经济 /民生: Currently $120,000 per year is spent by Hunter Valley councils to try and contain the weed (Coventry et al 2002). Liverpool (Australia) (Australia)   经济 /民生: Liverpool City Council spent $8,000 annually to reduce the visual impact from a bridge and to maintain a section of river available for use by a rowing club (Commonwealth of Australia, 2000). New Zealand   农业: Alternanthera philoxeroides is a pasture and horticulture weed. Stock sometimes suffer from a skin complaint, with increased sensitivity to sunlight, after contact with Alternanthera philoxeroides. It blocks drains and increases flood damage. Its ecological impacts are not well known (Bassett, I., pers. comm. July 2005). 滋扰人类: Alternanthera philoxeroides negatively affects recreational water use (Bassett, I., pers. comm. July 2005).