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Biodiversity, a multidimensional property of natural systems, is difficult to quantify partly because of the multitude of indices proposed for this purpose. Indices aim to describe general properties of communities that allow us to compare different regions, taxa, and trophic levels. Therefore, they are of fundamental importance for environmental monitoring and conservation, although there is no consensus about which indices are more appropriate and informative. We tested several common diversity indices in a range of simple to complex statistical analyses in order to determine whether some were better suited for certain analyses than others. We used data collected around the focal plant Plantago lanceolata on 60 temperate grassland plots embedded in an agricultural landscape to explore relationships between the common diversity indices of species richness (S), Shannon's diversity (H'), Simpson's diversity (D-1), Simpson's dominance (D-2), Simpson's evenness (E), and Berger-Parker dominance (BP). We calculated each of these indices for herbaceous plants, arbuscular mycorrhizal fungi, aboveground arthropods, belowground insect larvae, and P.lanceolata molecular and chemical diversity. Including these trait-based measures of diversity allowed us to test whether or not they behaved similarly to the better studied species diversity. We used path analysis to determine whether compound indices detected more relationships between diversities of different organisms and traits than more basic indices. In the path models, more paths were significant when using H', even though all models except that with E were equally reliable. This demonstrates that while common diversity indices may appear interchangeable in simple analyses, when considering complex interactions, the choice of index can profoundly alter the interpretation of results. Data mining in order to identify the index producing the most significant results should be avoided, but simultaneously considering analyses using multiple indices can provide greater insight into the interactions in a system.

1 cartel, There is no doubt of the serious impact of mining on the gypsicolous flora, especially the comparatively more restricted endemic taxa. Therefore, rehabilitation should aim particularly at the ecological recovery of the original environments. In this particular matter, the data on the subject of succession, a valuable concept to fully acknowledge the ecological systems, is essential when planning a restoration. In fact, nowadays there is a tendency towards the belief that succession ought and could be integrated within the planning strategy. The aim of this study is to overcome the lack of knowledge on successional stages in gypsum quarry rehabilitation processes in semiarid systems. The restoration strategy was mainly based on subsuperficial organic amendment (MSW compost) and topsoil replacement. The addition of organic amendment serves both physical (structural) enhancement and chemical (nutrient) reinforcement. Topsoil replacement on reclaimed mine lands is vital for improved infiltration, plant rooting media, enhanced nutrient cycling and as potential source of plant propagules to increase plant community diversity. A composition indicator (Berger – Parker index), at community – ecosystem level of organization, is suggested for monitoring gypsum quarry rehabilitation processes. The Berger – Parker index (measure of dominance) has been recommended as one of the most satisfactory diversity measures available. The rate of secondary succession was very fast. The pioneer stage lasted for only 1 year (Halogeton sativus), the tall weed stage 2 years (Moricandia arvensis), and the native perennial grass stage started in the fourth year (Brachypodium distachyon). Following the Berger – Parker index values, the vegetation could be divided into three succession stages, namely monodominant, subdominant and codominant species communities.