Ecologists have developed an abundance of conceptions and mathematical expressions to define β-diversity, the link between local (α) and regional-scale (γ) richness, in order to characterize patterns of biodiversity along ecological (i.e., spatial and environmental) gradients. These patterns are often realized by regression of β-diversity indices against one or more ecological gradients. This p...

Large terrestrial carnivores are important ecological components and prominent flagship species, but are often extinction prone owing to a combination of biological traits and high levels of human persecution. This study combines phylogenetic and functional diversity evaluations of global and continental large carnivore assemblages to provide a framework for conservation prioritization both bet...

Karin M. Kettenring*, Kristin L. Mercer, Carrie Reinhardt Adams and Jes Hines Ecology Center and Department of Watershed Sciences, Utah State University, Logan, UT, USA; Smithsonian Environmental Research Center, Edgewater, MD, USA; Department of Horticulture and Crop Science, The Ohio State University, Columbus, OH, USA; Department of Environmental Horticulture, University of Florida, Gainesvi...

seed dormancy has a critical role in ecological adaptation of wild plant species such as hordeum spontaneum, a wild relative of barley. in this study, 192 ecotypes of hordeum spontaneum maintained in national plant gene bank of iran (npgbi) originating from different climatic zones of the country were evaluated. morphological, phenological and physiological traits were recorded in the field. af...

The current growing body of evidence for diversity-disturbance relationships suggests that the peaked pattern predicted by the intermediate disturbance hypothesis (IDH) may not be the rule. Even if ecologists could quantify the diversity-disturbance relationship consistent with the IDH, the applicability of the IDH to land management has rarely been addressed. We examined two hypotheses related...

In the present study, some ecological factors were studied for Amphipoda at different depths. The Shannon, Margalef, and Hill indices were used to determine the  species diversity, richness and evenness, respectively. In addition, the association and niche overlap values were estimated. Indices of species richness and diversity were highest at 50 and 100m depths, respectively.  The or...

introduction weed infestation causes an extremely reduction of crops yield. on the other hand, increasing the diversity of crops in agro-ecosystems will change the biomass distribution of weeds community, thereby reducing the number and density of different weed species. weed management in the past few decades has been in conflict with ecological principles and sustainability of the production ...

livestock grazing and rangelands fire are important ecological disturbances influencing the vegetation and soil properties in rangelands ecosystem. this study was conducted to determine the effects of different burned treatments and distances from the water sources on some soil and vegetation properties of rangelands ecosystem. the experiment was conducted in lashgar dar rangelands. vegetation ...