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 ...

silvicultural operation need to notice the species diversity. to this study gomarlang district in marivan region, northern zagros forest was selected. in this study 30 circle sample plots (500 m2) were collected by random method. in every sample plot the kind of species and number of trees and shrub were recorded. in the sample plots the micro plots of 5 m by 5 m (i.e. area of 25 m2) were desig...

fire, as a natural ecological disturbance factor in forest, this study located in the marivan region, northern zagros forest, and western iranian state of kurdistan. in each burned and unburned area 30 circle sample plot (1000 m2) were collected by randomized–systematic method in the 100×200 m net (in total 60 plots). in every sample plot the kind of species, number of tree, the height of coppi...

Diversity indices are frequently applied in the form of ratios of absolute diversity to the maximum diversity possible. Regardless of whether the maximum diversity is defined to be limited by the number of species or by the number of individuals present, the resultant indices can be shown to possess mathematically undesirable qualities. All such indices, including equitability as measured by Pi...

Abstract The hydrological system of tropical peatland has been changed due to drainage. condition caused prone burning. Forest fire affected the vegetation composition in peatland. Repeated causes more severe impact on and change characteristics. aim study is obtain species after Central Kalimantan. research was conducted several plots observation that burned 2015 (three years forth frequency)....

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...

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...