杂草入侵背景下的云南嘉利泽湿地植物群落与种间的关系

Plant Community and Interspecies Association of Jialize Peat Bog Suffering Wild Grass Invasion

对云南嘉利泽泥炭沼泽进行了基于样方调查的植物多样性研究。野外调查表明:本区含66科137属的176种高等植物;其中外来入侵物种17种。176种植物中的82种,有5种外来杂草。在此基础上,采用双向指示种分析方法,对当地植物群落进行了分类,并采用χ2检验方法研究了30个主要物种种对间的关系。结果表明:1.采用TWINSPAN数量分类方法,将植被划分为12个群丛类型,分别为;莲-浮萍-满江红-黑麦草,黑麦草-野豌豆-艾蒿-三叶鬼针草,芸苔-黑麦草-狗牙根-三叶鬼针草,芦苇-黑麦草-狗牙根,蒲公英-黑麦草-三叶鬼针草-芦苇,狗牙根-三叶鬼针草-苦荬菜属,艾蒿-狗牙根-三叶鬼针草-空心莲子草-紫茎泽兰,狗牙根-芦苇-空心莲子草-狐尾藻,三叶鬼针草-空心莲子草-打碗花,三叶鬼针草-芦苇-龙葵,锦葵和毛茛-酸模-三叶鬼针草群丛。2.30种主要植物组成的435个种对中,正联结的种对占42.5%,负联结的种对占56.3%,完全无关联的种对占1.2%。显著正关联和显著负关联关系的缺乏表明:本区植物各物种独立性强,竞争关系也尚未完全建立。本研究暗示了除自然灾害和人为干扰外,外来入侵物种可能也是造成这种状况的原因之一。

The present work initiated a sampling-based phytodiversity survey of the Jialize peat bog,a ten-square kilometers wetland near Kunming,China. The field investigation performed on the bog including 52 quadrates and their neighboring regions was conducted in December,2010. The bog recorded to the inventory a total of 176 plant species that belong to 137 genera and 66 families,of which 17 plant species are invasive. The 52 sampling quadrates registered 82 plant species,about 60% of the total plant species in the bog,of which five are invasive. The plant communities in the bog were classified by using two-way indicator species （ TWINSPAN） method,and their interspecific associations of 30 dominant species were analyzed by using χ2-test. Twelve communities are classified,namely Comm. Nelumbo nucifera-Lemna minor-Azolla imbircata-Lolium perenne,Lolium perenne-Vicia sepium-Artemisia argyi-Bidens pilosa,Brassica sp. -Lolium perenne-Cynodon dactylon-Bidens pilosa, Phragmites australis-Lolium perenne-Cynodon dactylon,Taraxacum sp. -Lolium perenne-Bidens pilosa-Phragmites australis,Cynodon dactylon-Bidens pilosa-Ixeris sp. ,Artemisia argyi-Cynodon dactylon-Bidens pilosa-Alternan- thera philoxeroides-Eupatorium adenophorumk, Cynodon dactylon-Phragmites australis-Alternanthera philoxeroides-Myriophyllum verticillatum,Bidens pilosa-Alternanthera philoxeroides-Calystegia hederacea,Bidens pilosa-Phragmites australis-Solanum nigrum,Malva sinensis,and Ranunculus japonicus-Rumex acetosa-Bidens pilosa. In the plant communities 435 species dyads consisting of 30 dominant plant species were selected and run with χ2 -test. Of the species dyads 42. 5% ,56. 3% and 1.2% were positively,negatively and null associated,respectively. No significant levels of either positive or negative associations are found in the plant species dyads, suggesting that the plant species under survey act as the pioneers and experience the initial stage of colonizing the region of the Jialize peat bog,suffering human activities and invasive grasses as recorded,and that this area is far from a biodiverse steady ecosystem.