Studies on niche characteristics and interspecific association of main populations in submerged communities invaded by Cabomba caroliniana
水盾草入侵沉水植物群落主要种群生态位和种间联结研究

The niche characteristics and interspecific association of populations in submerged communities invaded by Cabomba caroliniana were studied.24 communities have been carried out and the niche breadths,niche overlaps,multi-interspecies association,and pair-interspecies association of 13 populations are obtained on the investigation.The results showed that:(i) Among the 13 populations,the niche breadth of C.caroliniana is the biggest,and Ceratophyllum demersum,Hydrilla verticillat,and Vallisneria natans is minor.(ii) C.caroliniana has greater niche overlaps with C.demersum,H.verticillata,V.natans,and Utricularia aurea,and those between C.caroliniana and other populations are smaller.(iii) C.caroliniana has positive association with C.demersum,V.natans and H.verticillata,and association with other populations is not significant that they occur independently.It can be seen that the rapid invasion of C. caroliniana has great negative effects to familiar native species,and it can also bring decline to species diversity in communities.Controlling the spread of C.caroliniana should be strengthened.