Investigation And Study On Exotic Invasive Plants In Putuoshan Island,Zhejiang Province

Alien invasive plants have huge negative impacts on the biodiversity and ecology security of native ecosystems.In order to understand the situation of invasive plants in Putuoshan Island,Zhejiang province,we conducted sample survey by region.According to the weighted statistics of distribution area,coverage and the invasion national level,the harm degree and invasion grade of various invasive plants were assessed,and the key harm areas and prevention and control areas of invasive plants in Putuoshan Island were determined.The main results are summarized as follows1.A total of 21 families,37 genera,48 species of exotic invasive plants(including subspecies,varieties and forma)in Putuoshan Island were documented.There were 15 species in Compositae,5 species in Convolvulaceae,4 species in Gramineae,3 species in Leguminosae,2 species in each of Amaranthaceae,Euphorbiaceae,Umbelliferae,Solanaceae,and one species in Oxalidaceae,Labiatae,Chenopodiaceae,Nyctaginaceae,Phytolaccaceae,Basellaceae,Caryophyllaceae,Cruciferae,Haloragidaceae,Scrophulariaceae,Plantaginaceae,Campanulaceae,Pontederiaceae,respectively.These exotic invasive plants were all herbaceous,including 32 species of annuals or biennials herbs,accounting for 66.67%of the total species;9 species of perennial herbs,accounting for 18.75%;7 species of herbaceous climber,accounting for 14.58%2.Of all the exotic invasive plant species recorded,37 species were from the America,accounting for 77.08%of the total species;8 species were from Europe,accounting for 16.67%;5 species were from Africa accounted for 10.42%;5 species were from Asia,which accounted for 10.42%;3 species come from Oceania,accounting for 6.25%.Tropical plants were the major players.In addition to the 13 cosmopolitan genera,18 genera,22 species were commonly distributed in tropical zone,and 6 genera,7 species in temperate zone,which comprised the majority of malignant invasive and serious invasive species.47.92%(23 species)of all the invasive species were of grade 1 and 2;41 species invaded Putuoshan Island through exclusion and allelopathy;23 species,which accounted for 47.92%of the total invasive species,were categorized as moderate invaders causing enormous damages3.Hillyland,desolated land and coastal wetland are the regions of fundamental importance for preventing and controlling exotic invasive plant species in Putuoshan Island.Based on the factors such as invasion grade,invading area and damage degree,6 exotic invasive plant species in Putuoshan Island were the focal species of prevention and control,including Alternanthera philoxeroides,Phytolacca americana,Ipomoea lacunose,Ipomoea triloba,Solidago canadensis and Cenchrus echinatusGiven current situation of Putuoshan,it is highly recommended to increase efforts to propaganda,and raise the public awareness of the detriment that can be brought by exotic invasive plants.In addition,strengthening the dynamic monitoring and superintending the highly susceptible regions in Putuoshan are of crucial importance in protecting its native ecosystems.Furthermore,fortifying plant inspection and quarantine and evaluating its risk before application are essential to keep the waters clear and mountains lush in Putuoshan.