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Environmental gradients across wetland vegetation groups in the arid slopes of Western Alborz Mountains, N. Iran

100%
Kamrani A., Naqinezhad A., Jalili A., Attar F.
Acta Societatis Botanicorum Poloniae
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2010
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tom 79
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nr 4
Mountain wetlands are unique ecosystems in the arid southern slopes of Alborz range, the second largest range in Iran. The spatial distribution characteristics of wetland vegetation in the arid region of the Alborz and the main factors affecting their distributional patterns were studied. A classification of vegetation and ecological characteristics were carried out using data extracted from 430 relevés in 90 wetland sites. The data were analyzed using Two Way Indicator Species Analysis (TWINSPAN) and detrended correspondence analysis (DCA). The wetland vegetation of Alborz Mountain was classified into four large groups. The first vegetation group was calcareous rich vegetation, mainly distributed in the river banks and characterized by helophytes such as Bolboschoenus affinis as indicator species. The second group was saline transitional vegetation, distributed in the ecotone areas and dominated by Phragmites australis. The third vegetation group is wet meadow vegetation which mainly consists of geophytes, endemic and Irano-Turanian species, distributed in the higher altitudes. This vegetation is mainly characterized by indicator species such as Carex orbicularis, high level concentration of Fe2+ and percentage of organic matter in the soil. The fourth vegetation group is aquatic vegetation, distributed in the lakeshores. The aquatic group species are mainly hydrophytic such as Batrachium trichophyllum. The TWINSPAN vegetation groups could be also recognized in the DCA graphs and ecologically differentiated by ANOVA of studied variables. Four vegetation groups can be differentiated on two first axes of indirect ordination. There is a gradient of pH, EC and organic matter associated with altitude on the DCA diagram. Correlation analysis between the axes of DCA and environmental factors shows that altitude, soil texture and other dependant environmental variables (e.g. pH) are the main environmental factors affecting the distribution of wetland vegetation groups.
2
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Pollen morphology of Amygdalus L. [Rosaceae] in Iran

100%
Vafadar M., Attar F., Maroofi H., Mirtadzadini M.
Acta Societatis Botanicorum Poloniae
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2010
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tom 79
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nr 1
63-71
Pollen grain of 16 species and three hybrids of the genus Amygdalus L., representing two subgenera and two sections distributed in Iran were examined by light and scanning electron microscopy. All pollen grains are tricolporate. The shape of grains varies from subprolate through prolate. Regarding outline, in polar view, pollen grains are triangular-circular and in equatorial view, elliptic. Regarding sculpturing of exine, the frequent type like many members of family Rosaceae is striate with or without perforations that can be subdivided into three subtypes: type I (A-B), type II (A-B) and type V. In three species, A. trichamygdalus, A. spinosissima and A. orientalis, exine sculpture type is completely different. In the first species is rugulate, in the second species is reticulate and in A. orientalis, it is gemmate-perforate. Ornamentation of ridges (muri) in the striate sculpture is parallel to ectocolpus. Number of perforations in tectum, diameter of them, striae intervals and the thickness of ridges varies among studied taxa. The striae have different depth and slope. Results showed that among pollen grain characters, shape is useful character solely for separating of taxonomic ranks in Iranian Amygdalus specially in subgeneric or section level.
3
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Leaf indumentum types in Potentilla [Rosaceae] and related genera in Iran

88%
Faghir M. B., Attar F., Farazmand A., Ertter B., Eriksen B.
Acta Societatis Botanicorum Poloniae
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2010
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tom 79
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nr 2
139-145
Indumentum types of the leaves in 31 species of Potentilla L. (Rosaceae) and four related genera, especially Tylosperma Botsch., Schistophyllidium (Juz. ex Fed.) Ikonn., Drymocallis Fourr. ex Rydb., and Sibbaldia L. from Iran were investigated. Indumentum ultrastructure was studied by scanning electron microscopy (SEM). SEM observation revealed three type classes based on leaf indumentum: 1) straight (appressed-erect); 2) straight-erect and crispate, and 3) crispate-floccose. The straight hair character (I type class) is widely distributed among all genera sampled and six sections of Potentilla. In contrast the crispate-floccose indumentum (III type class) is confined to all examined species of sections Speciosae and Pensylvanicae. While some sections especially Rectae (straight and straight-crispate hairs) and Terminales (straight-crispate and floccose-crispate) posses two indumentum type classes. The present survey shows that indumentum types are of systematic importance and may form good key characters for identification purposes.
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