The Systematic Classification And Floristic Geography Of Primulaceae In Gansu Province

The systematic classification and floristic geography of Primulaceae in GansuProvince were studied in this thesis.The all species of the family Primulaceae weretried to recognize in Gansu province based on herbarium examinations of more thanone thousand eight hundreds specimens from five herbaria(abbreviated as PE、WUK、LZU、 QTPMB、 GAUF), literatures and additional filed work, they had alsocontributed to reveal the main morphological characters and their evolution studies.Based on the materials of systematic classification and geographic distribution, themodern geographic distribution patterns(distribution types) of all species and generain this region were classified and taken into statistical analysis. And used similaritycoefficient analysis to compare with adjacent regions to display the geographicaldistribution features, floristic elements, the relationship of floristic similarity and thefloristic origin of the family Primulaceae in Gansu. The results were summarized asfollows:1.8genera and86species (include77species,4subspecies and5varieties) ofthe family Primulaceae were recognized in Gansn province;Morphological description,localities, habitats and specimens cite were given in detail and systematic key to thegenera and species had been made.2. Androsace septentrionaIis L．、 Androsace paxiana R. Knuth、Androsaceaxillaris (Franch.) Franch.、Androsace squarrosula Maxim.、and Androsace integra(Maxim.) Hand.-Mazz. of the Androsace were recognized as new records speciesdistributed in Gansu province；Androsace septentrionaIis L．in China mainly in Eastern the Inner Mongolia Autonomous Region, northern Hebei and NorthernXinjiang，indicator taxa for Flora migration routes；Androsace paxiana R. Knuth wasmain production in the Sichuan Mount Emei and Guanxian. Provide a new evidencefor the phylogenetic relationship of the middle part of Hexi Corridor, the QilianMountains north area and northeast mountain flora.3. Primula geraniifolia J. D. Hooker、Prinula palmate Hand.-Mazz.、Primulanivalis Pall.、Primula sinopurpurea Balf. f. ex Hutch.、Prirmula szechuanica Pax、Primula prattii Hemsl.、Primula sertulum Franch.、Primula sieboldii E. Morren、Primula poissonii Franch.、Primula tangutica Duthie var. flavescens Chen et C. M.Hu、Primula calthifolia W. W. Smith、Primula secundiflora Franch. and Primulaknuthiana Pax of the Primulaceae were recognized as new records species distributedin Gansu province.4. Lysimachia stellarioides Hand.-Mazz.、Lysimachia circaeoides Hemsl. andLysimachia paridiformis Franch var.stenophylla Franch. of the Lysimachia wererecognized as new records species distributed in Gansu province.5.Cortusa matthioli L. was recognized as new record species distributed in Gansuprovince.6. According to different areal divisions,the geographic distribution ranges of thefamily in Gansu were divided into8regions: among the mountains area in theMiddle-upper reaches of the upstream mountainous district Taohe-Xiahe and themountains area in southern Qinling was seemed to be the centre of the distributiondensity and the species diversity of Primulaceae in Gansu province.7.It was abundance in species and diversity in forms of the family Primulaceae inGansu；the china only and Gansu only species were obvious；and the temperatedistribution elements of the flora of Primulaceae in Gansu were absolutely dominant.8.There were higher floristic similarity of genera and species between Gansu andshanxi, Sichuan as well as Tibet, but the similarity coefficient between Qinhai,InnerMongolia,xinjiang as well as Ninjiang was lower; all of above indicated that thewestern the Hengduan Mountains and East Himalaya of china was the distributioncenter of Primulaceae, the more far from this center the more poor in species of the family Primulaceae.9.Lastly, it can be regarded that the western highland regions of china was quitepossible the location of its origin. The principal reasons of the floristic developmentand their areal division of the family in Gansu may be summed up in the migrationand differentiation of the species. they were also assumed that western region of chinaand eastern Himalayas.