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Plant seeds exhibit many species-specific traits, thus potentially being especially helpful for forensic investigations. Seeds of a broad range of plant species occur in soil seed banks of various habitats and may become attached in large quantities to moving objects. Although plant seeds are now routinely used as trace evidence in forensic practice, only scant information has been published on this topic in the scientific literature. Thus, the standard methods remain unknown to specialists in such botanical subjects as plant ecology and plant geography. These specialists, if made aware of the forensic uses of seeds, could help in development of new, more sophisticated approaches. We aim to bridge the gap between forensic analysts and botanists. Therefore, we explore the available literature and compare it with our own experiences to reveal both the potential and limits of soil seed bank and seed dispersal analysis in forensic investigations. We demonstrate that habitat-specific and thus relatively rare species are of the greatest forensic value. Overall species composition, in terms of species presence/absence and relative abundance can also provide important information. In particular, the ecological profiles of seeds found on any moving object can help us identify the types of environments through which the object had travelled. We discuss the applicability of this approach to various European environments, with the ability to compare seed samples with georeferenced vegetation databases being particularly promising for forensic investigations. We also explore the forensic limitations of soil seed bank and seed dispersal vector analyses. [ABSTRACT FROM AUTHOR]

Small-scale landscape elements, such as ditch banks are an important remaining source of biodiversity in many agricultural landscapes, including the Western Peat District in the Netherlands. Unfortunately, plant species richness is declining even in these habitats. To understand the factors threatening biodiversity, we studied demographic traits (occupancy, trend, colonisation and extinction) for a large number of plant species, in a 25-year long data set. We developed a method to investigate the relative importance of colonisation and extinction for species increase and decrease in multi-species assemblages. We show that colonisation has been more important for determining species trends than extinction. Decreasing species were small and characterised by low nutrient tolerance and high light requirements, indicating that competitive ability influences species trends. The mechanism by which high nutrient levels reduce plant diversity appears to be closely related to colonisation (germination and seedling establishment). Local management should therefore continue to focus on nutrient reduction and the creation of regeneration sites. Yet, these measures will be insufficient for restoring species richness since isolation also hampers species increase. Therefore, to maximise the effects of local management, additional regional management solutions are required to improve seed dispersal for example, from nature reserves. [Copyright &y& Elsevier]

• • We provided a forest development stage assessment method for the plot-based vegetation surveys. • • For this we used data from forest management plans and traditional vegetation surveys. • • The method gave a very realistic division and characteristics of the developmental stages. • • However, quantification of the proportion of the development stages in the forest was unsatisfactory. • • Distinguished stages were characterised by a separate herb layer species composition. The possibility to distinguish changes in vegetation related to the dynamics of the forest stand and / or the regimes of forest management from directional or random changes would allow for more precise recognition, and counteracting the effects of global threats. However, in most cases, records for particular periods of vegetation surveys do not contain data allowing assessment of the forest stand dynamic. In this work, we provided the forest developmental stages assessment method using variables recorded on the sampling plots designed for vegetation surveys, supplemented by variables from forest inventories conducted in managed European beech forests from the Carpathian Mountains. Three distinct forest stages were distinguished. Based upon distribution of variables, specific for individual stages, we classified them as growing (G), optimum (O), and terminal (T) stage. The characteristics of these stages were similar to those for old-growth forests European beech forests. Our results demonstrated a simple, clear and repeatable method of using forest inventories and data from traditional vegetation surveys, useful in the assessment of managed forest stands for long term study purposes. It was possible based on 10 variables, among which the most decisive seems to be stocking, tree regeneration and mean tree DBH and height. As each of the distinguished stages were characterised by a separate herb layer species composition, the method allows for better identification of the impact of cyclical changes in the structure of the stand from the directional causes of long-term changes in forest herbaceous vegetation. Although our method gave a very realistic division and characterisation of the developmental stages, due to the bias of vegetation researchers (who more often conducted research in the optimum stage of the forest), does not allow for the correct quantification of the proportion of developmental stages in the forest. [ABSTRACT FROM AUTHOR]

• Extending the plant-based bioindication systems to European scale is urgently needed. • Large mire vegetation databases should be calibrated with hydrological estimates. • We present ecological indicator values and tolerances for most European mire plants. • The system well captured water table depth (WTD), soil moisture and zoological data. • Inclusion of bryophytes and drought tolerances improved the indication of WTD. Bioindication systems based on the occurrence of plant species are widely used in vegetation science, palaeoecology, community ecology, geographical modelling and global change biology. Although the existing systems are mostly regional, the development of large-scale vegetation databases calls for the establishment of a pan-European indication system. Here we present the first step towards this goal, by assessing indicator values for soil moisture and water table depth in European mires and associated grasslands. For each vascular plant and bryophyte species occurring in 24,091 vegetation-plot records of European mires, we developed an updated system of Ellenberg-like Ecological Indicator Values (EIVs) at the scale of 1–12 (species optimum) including ecological valences – minimum value (drought intolerance), maximum value (flooding tolerance) and range of values (tolerance), using both statistical and expert-based approaches for species co-occurrence data. Spearman correlation coefficients, Akaike Information Criterion (AIC) and Akaike weights were used to assess the performance of the updated EIVs against measured soil moisture and water table in two Central-European datasets, and against the proportion of aquatic mollusc species in a European-scale dataset. The updated EIVs performed well in all cases, having stronger correlations with directly measured water table and the combined proportion of aquatic and wetland molluscs than the original EIVs. The original EIVs, however, performed better with soil moisture. In the Central-European datasets, the use of minimum values (drought intolerances) of the updated EIVs weighted by species covers and/or tolerances led to the highest correlations with water table in all cases. This improvement of the indication potential on the regional scale is mainly related to the inclusion of bryophytes into the updated EIVs. Our data show that the updated EIVs are beneficial not only when used in the cross-regional or pan-European datasets, but also when water table rather than soil moisture is to be indicated in the regional-scale data, as it occurs frequently in bryological, zoological and protistological research. Overall, this study demonstrates how EIVs can be updated by including previously omitted taxa of vascular plants and bryophytes and adding ecological valences to reflect accurate conditions of natural habitats at the continental scale. [ABSTRACT FROM AUTHOR]