从澳大利亚引进软树蕨苗木的风险评估

Invasion Risk Analysis of Soft Tree Fern Seedlings from Australia

软树蕨是常青的陆生蕨类植物,体型高大,为澳大利亚特有物种,对光照水肥等生境要求较高,多被引种栽植于庭园温室内。采用Maxent生态位模型根据现有分布点及环境变量运算出预测模型,再结合地理信息系统ArcGIS绘制软树蕨在我国的适生等级预测图,结果表明软树蕨在我国的适生范围较小,仅包括台湾大半部地区和云南、福建3个省份,西藏、广西、湖南、江西、浙江有零星中适生区分布。并对从澳大利亚引进软树蕨苗木可能传带有害生物的风险进行分析,研究表明:软树蕨在自然环境下基本无病害,但温室条件下易引发猝倒病、顶枯病,或受蚂蚁、蜗牛为害,可通过常规防治手段进行控制,引入风险较低,建议首先小批量引进软树蕨苗木并定期监控和记录。

Dicksonia antarctica(soft tree fern,man fern)is a unique species of evergreen tall tree fern in Australia.It has fastidious demands for habitats such as light,water and fertilizer,and mostly is introduced and planted in gardens and greenhouses.The maximum entropy model(Maxent)was used to combine with the Geographic information system ArcGIS to generate the suitable level prediction map of D.antarctica in China.The results showed that only several medium suitable areas of soft tree ferns was found in China,including most parts of Taiwan,Yunnan and Fujian,as well as very few parts of Tibet,Guangxi,Hunan,Jiangxi,and Zhejiang.Also,the risk of pests carried by soft tree ferns from Australia was analyzed.The soft tree ferns basically could not be infected by pest in natural environment,but vulnerable to damping-off,tip blight,ants and snails in greenhouse conditions,which could be easily controlled by conventional control means.Above all,the introducing risk of soft tree ferns was low,small amounts of soft tree fern seedlings were recommended to introduce in advance and with periodical monitoring.