Tarbiat Modares University (TMU) ECOPERSIA 2322-2700 8 4 2020 09 01 Environmental Factors Affecting the Structural Trials and Biomass of Onobrychis aurea Bioss 247 259 17301 EN J. Motamedi Rangeland Research Division, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran J. Afradi East Azarbaijan Agricultural and Natural Resources Research Center, Agricultural Research Education and Extension Organization (AREEO), Tabriz, Iran E. Sheidai Karkaj Faculty of Agriculture and Natural Resources, Urmia University, Urmia, Iran A. Alijanpour Faculty of Agriculture and Natural Resources, Urmia University, Urmia, Iran I. Emadodin Institute for Crop Science and Plant Breeding, Grass and Forage Science, 24118 Kiel Kiel, Germany Sh. Banej Shafiei Desert Research Division, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran E. Zandi Esfahan Rangeland Research Division, Research Institute of Forests and Rangelands, Agricultural Research Education and Extension Organization (AREEO), Tehran, Iran Journal Article 1970 01 01 <strong>Aims:</strong> Recognizing the environmental factors affecting plants structural trials and biomass is important to conserve plants as well as their ecosystem function, and services. <em>Onobrychis aurea</em> is a valuable forage that is distributed in the marl lands and is considered as an endangered plant species in Iran. In the present study, the ecological characteristics (plant traits) of this species has been investigated in detail.<br> <strong>Materials & Methods:</strong> For this purpose, structural traits and biomass of <em>O. aurea</em> were investigated in 12 ecological units with different topographical and soil conditions. Three soil samples were taken to 15cm depth, (0-15cm) in each ecological unit. The relationship between structural traits and species biomass with environmental factors was tested by redundancy analysis (RDA) method in 2016.<br> <strong>Findings:</strong> The results indicated that the soil characteristics including clay, lime and silt content play a more important role in the structural and biomass traits of <em>O. aurea</em> evidence show. Spatial and topographical factors, especially elevation and geographical aspects, had a smaller contribution in structural traits and species biomass in comparison with soil factors. Higher structural values were recorded in heavy textured alkaline soils. The slope percentages also have no significant effect on plant characteristics.<br> <strong>Conclusion:</strong> The present study indicated that the soil and topographic factors are very important for management of <em>O. aurea</em>. In general, it should also be emphasized that having good knowledge related to plant ecology as well as environmental condition could help managers to conserve and rehabilitate endangered plants. https://ecopersia.modares.ac.ir/article_17301_b3f25f67fa7662dec75e006a97770e6c.pdf