In nature, plant biomass is not evenly distributed across species, and naturally uncommon species may differ from common species in the probability of loss from the community. Understanding relationships between evenness and productivity is therefore critical to understanding changes in ecosystem functioning as species are lost from communities. We examined data from a large multi-site grasslan...

rangeland ploughing and cultivation using dry land farming crops may be amajor reason for the destruction of natural resources in the semiarid and sub-humid regionswhich may significantly change the composition and reduce the stability of the affectedcommunities. in present research, an abandoned ploughed site was compared with a nearbyreference site in the semiarid rangelands of baharkish, quc...

the aim of this study is comparison of soil characteristics and biodiversity in plantation of bald cypress and caucasian alder forest stands in kludeh region (mazandaran province). in order to study biodiversity in forest stands and control region, 10 sample plots (releve) were selected and the name and abundance of plant species of the forest floor were recorded. biodiversity of herbal plants ...

gradual decrease of biodiversity related to the rapid industrialization and urbanization is stimulating the fundamental research towards a better understanding of the relationships between biodiversity and ecosystem functioning. present study emphasizes the nature and status of floral diversity in the vicinity of integrated industrial estate-pantnagar, uttarakhand, india (iie-pantnagar).three m...

Consumer and resource control of diversity in plant communities have long been treated as alternative hypotheses. However, experimental and theoretical evidence suggests that herbivores and nutrient resources interactively regulate the number and relative abundance of coexisting plant species. Experiments have yielded divergent and often contradictory responses within and among ecosystems, and ...

The amount of variation in species composition among sampling units or beta diversity has become a primary tool for connecting the spatial structure of species assemblages to ecological processes. Many different measures of beta diversity have been developed. Among them, the total variance in the community composition matrix has been proposed as a single-number estimate of beta diversity. In th...

Various properties have been advocated for biological evenness indices, with some properties being clearly desirable while others appear questionable. With a focus on such properties, this paper makes a distinction between properties that are clearly necessary and those that appear to be unnecessary or even inappropriate. Based on Euclidean distances as a criterion, conditions are introduced in...

The design of road surfaces involves application a sophisticated algorithm system based on mathematical calculations and engineering solutions, with the calculation evaluation criteria. It is precisely observance standardized requirements in terms criteria that makes it possible to consider pavement as reliable, safe convenient for traffic during specified service life. When calculating strengt...