汉中地区汉水流域水生维管植物种类及地理分布

经野外调查，采集标本与鉴定分析，汉中地区汉水流域共有水生维管植物69种，包括蕨类植物3种，种子植物66种，分别隶属于32科48属。其中挺水植物41种，浮水及浮叶植物11种，沉水植物17种。66种种子植物分别隶属于46属，有7种地理分布类型，其中以世界分布类型成分居多，共21属，占本地区水生种子植物总属数的45．7％；热带分布类型成分13属，占28．3％，温带分布类型12属，占26．0％。调查分析发现8种6该区域的新分布种，即：竹叶眼子菜，南方眼子菜，小茨藻，大茨藻，水毛花，穗花狐尾藻，有梗石龙尾的狸藻；新记录属4个，即：茨藻属，狐尾藻属，石龙尾属和狸藻属；新记录科2个，即；茨藻科和小二仙草科。

The species and distribution of the water vascular plants at the Han river basin in Hanzhong,Shaanxi Province

Based on the preliminary survey and analysis,there are 69 species water vascular plants which include 3 species pteridophyte,66 species seed plants and belong to 32 families 48 genera at the Han River basin in Hanzhong,Shaanxi Province.In these plants,41 species belong to straight hydrophyte,11 species belong to natant hydrophyte and 17 species are submersed hydrophyte.The 66 species seed plants belong to 46 genera and 7 areal type of genera of seed plants.There are 21 genera which belong to cosmopolitan type,13 genera belong to the tropical type and 12 genera belong to the temperate type.Through analysis we have discovered that in this region there are eight new recorded species which are Potamogeton crispus,P.octandrus,Najas minor,N.Marina,Scirpus triangulates,Myriophyllum spicatum,Limnophila india and Utricularia vulgaris ;four new recorded genera which are Najas,Myriophyllum,Limnophila and Utricularia ,two new recorded familis which are Najadaceae and Haloragidaceae.