While many studies have shown that urbanization and land-use type significantly impact species richness and evenness, few studies have investigated the mechanisms by which these changes occur. A residential neighborhood at ASU-Polytechnic Campus has been designed with 4 different neighborhood landscape regimes and provides the ideal opportunity to explore how local neighborhood landscaping affe...

Climatic change is expected to have differential effects on ecological communities in different geographic areas. However, few studies have experimentally demonstrated the effects of warming on communities simultaneously at different locales. We manipulated air temperature with in situ passive warming and cooling chambers and quantified effects of temperature on ant abundance, diversity, and fo...

There exist different types of concentration and evenness measures. What they have in common is the fact that they all try to measure inequality. We will discuss only concentration measures that describe the scatter of items over sources, and this irrespective of the number of sources considered. Concentration measures can, e.g., be used as indicators for the convergence, or divergence of regio...

The signal strength of a biweight site chronology is properly viewed as an outcome of analysis rather than as aproperty of the forest-climate system. It can beestimated by theevennessof theempirical weights that are assigned to individual trees. The approach is demonstrated for a 45-year biweight chronology obtained from 40 jack pine (Pinus banksiana Lamb.) trees. The annual evenness of the emp...

Diversity (or biodiversity) is typically measured by a species count (richness) and sometimes with an evenness index; it may also be measured by a proportional statistic that combines both measures (e.g., Shannon-Weiner index or H'). These diversity measures are hypothesized to be positively and strongly correlated, but this null hypothesis has not been tested empirically. We used the results o...

Recent attitude of vegetation assessors is using of new ecologic approaches to evaluate and analyse the complex rangeland ecosystems. Plant diversity is the most important indices to assess the ecological changes of rangelands. In order to survey of plant indices of rangelands, two exclosure areas (long-term and mid-term) and a grazing area in rangelands of Javaherdeh (Ramsar, Iran) were select...

Bark beetles (Coleoptera, Scolytinae) carry a diverse filamentous fungal community sometimes acting as vectors or carriers of phytopathogens. In this study, mycobiota carried by two Tomicus species (Tomicus piniperda and Tomicus destruens) were investigated through (i) morphological and molecular identification of taxa; (ii) taxonomic richness, diversity, evenness, dominance and phoresy indices...