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An improved iteratively re-weighted factor analysis procedure is presented to interpret engineering geophysical sounding logs in shallow unsaturated sediments. We simultaneously process cone resistance, electric resistivity and nuclear data acquired by direct-push tools to give robust estimates of factor variables and water content in unconsolidated heterogeneous formations. The statistical procedure is based on the iterative re-weighting of the deviations between the measured and calculated data using the Most Frequent Value method famous for its robustness and high statistical efficiency. The iterative approach improves the result of factor analysis for not normally distributed data and extremely noisy measurements. By detecting a strong regression relation between one of the extracted factors and the fractional volume of water, we establish an independent method for water content estimation along the penetration hole. We verify the estimated values of water volume by using a highly overdetermined quality checked interval inversion procedure. The multidimensional extension of the statistical method allows the estimation of water content distribution along both the vertical and horizontal coordinates. Numerical tests using engineering geophysical sounding data measured in a Hungarian loessy-sandy formation demonstrate the feasibility of the Most Frequent Value based factor analysis, which can be efficiently used for a more reliable hydrogeophysical characterization of the unsaturated zone. This article is protected by copyright. All rights reserved

Questions Did high densities of wild ungulates cause a decline in plant species richness in a temperate oakwood? How did species composition change after nearly five decades? Did ungulates facilitate the spread of ruderal species and supress endangered species? Did dispersal strategies play a role in these processes? Location Krumlov Wood, SE Czech Republic. Methods In 2012, we resampled 58 quasi-permanent vegetation plots first surveyed in 1960s. Between the surveys, 36 plots were enclosed in a game preserve with artificially high density of ungulates (mostly deer, mouflon and wild boar; ca. 55 animals per square km). We analysed the differences in temporal changes between plots inside and outside the game preserve, focusing on species diversity and composition. We assessed species characteristics relevant to grazing to understand compositional changes. Results Ungulates significantly increased alpha and gamma diversity and caused significant vegetation homogenization inside the game preserve. Vegetation homogenization and the increase in species richness resulted from massive enrichment by ruderal species. However, richness of endangered species decreased. Species dispersed by animals internally (endozoochory) increased, while species dispersed externally (epizoochory) or by wind (anemochory) decreased. Conclusions Contrary to our expectations, our long-term data showed that artificially high ungulate densities substantially increased plant species richness. Apparently, the establishment of ruderal herbs was supported by frequent disturbances and ungulate-mediated dispersal. At the same time, species richness of non-ruderal plants did not change, probably because ungulates hindered the regeneration of woody species and maintained an open forest canopy. In conclusion, high ungulate density led to the spread of ruderal species, which in turn strongly contributed to the observed shift towards nutrient-richer conditions and taxonomically more homogenous communities. This article is protected by copyright. All rights reserved.

An extreme windstorm that took place on 7 December 1868 in the Czech Lands is analysed by means of rich documentary evidence from narrative sources, damage records, forestry journals and newspapers. Early meteorological measurements and a numerical atmospheric reanalysis support the documentary reconstruction. The windstorm reached hurricane-force over the Czech Lands between 0900 and 1600 of local mean time and was related to the passage of a cold front. The high winds, achieving hurricane-force, led to loss of human lives and many other casualties, as well as to severe damage to buildings and other structures. In particular, the documentary sources facilitate a quantitative reconstruction of the massive windthrow that occurred in forested areas across the Czech Lands, where the windstorm damaged at least 8 million cubic metres of timber, which is arguably more than has been lost to any single similar event since. Reasons for the extreme windthrow, apart from wind forces and destabilization arising from wet and thawed soils, were found in increased vulnerability arising out of old, dense and mono-species conifer stands and inadequate clear-cutting and thinning measures. For the Czech Lands, this event was the most damaging windstorm in the 19th century. Moreover, damage reports are found from the British Isles, the Netherlands, Belgium and Germany to Austria, the Czech Lands and Poland, documenting its disastrous effects on a (sub-)continental scale.

Forests cover approximately one-third of Central Europe. Oak (Quercus) and European beech (Fagus sylvatica) are considered the natural dominants at low and middle elevations, respectively. Many coniferous forests (especially of Picea abies) occur primarily at midelevations, but these are thought to have resulted from forestry plantations planted over the past 200 years. Nature conservation and forestry policy seek to promote broadleaved trees over conifers. However, there are discrepancies between conservation guidelines (included in Natura 2000) and historical and palaeoecological data with regard to the distribution of conifers. Our aim was to bring new evidence to the debate on the conservation of conifers versus broadleaved trees at midelevations in Central Europe. We created a vegetation and land-cover model based on pollen data for a highland area of 11,300 km2 in the Czech Republic and assessed tree species composition in the forests before the onset of modern forestry based on 18th-century archival sources. Conifers dominated the study region throughout the entire Holocene (approximately 40-60% of the area). Broadleaved trees were present in a much smaller area than envisaged by current ideas of natural vegetation. Rather than casting doubt on the principles of Central European nature conservation in general, our results highlight the necessity of detailed regional investigations and the importance of historical data in challenging established notions on the natural distribution of tree species.

Heterogeneous copper catalysts were prepared by the deposition of CuI on a hybrid material consisting of silica and a polymer with imidazolium moieties. The solid materials were characterised using solid‐phase NMR, Fourier transform infrared, Raman and X‐ray photoelectron spectroscopies and Brunauer– Emmett–Teller measurements. The formation of copper–carbene complexes was proved from Raman spectra and the results were supported by density functional theory calculations. The catalyst could be recycled efficiently with low loss of copper. Metal leaching was proved to be facilitated by the use of conditions typical for a homogeneous system (the presence of a polar solvent or the addition of a tertiary amine). Besides simple model reactions, the best catalyst was found to be suitable for the synthesis of triazoles of more elaborate structure, such as ferrocene or steroid derivatives.

This paper examines the possibilities of creating quantified models of past human activities in both time and space. The study area lies in the southeastern Czech Republic and western Slovakia. The spatio-temporal model of behavioural categories was calculated with the help of Monte Carlo simulations and statistical testing. One of the main advantages of our approach is that it admits the probabilistic nature of input data, quantifies them and provides probabilistic results comparable with other proxies. It also presents a less biased way of how archaeological data from regions and periods with low numbers of 14C datings can be incorporated into models of past population dynamics.

The term 'historical ecology' has been used with various meanings since the first half of the 20th century. Studies labelled as historical ecology have been produced in at least four academic disciplines: history, ecology, geography and anthropology. Although all those involved seem to agree that historical ecology concerns the historical interconnectedness of nature and human culture, this field of study has no unified methodology, specialized institutional background and common publication forums. Knowledge of the development of historical ecology is also limited. As a result, the current multitude of definitions of historical ecology is accompanied by divergent opinions as to where the origins of the field are to be sought. In this review, I follow the development of historical ecology from the 18th century to the present. In the first part, I briefly describe some early examples of historical ecological investigations, followed by a description of the various scientific strands in the 20th century that contributed to the formation of historical ecology. In the second part, I discuss the past five decades of historical ecological investigations in more detail, focusing mostly (but not exclusively) on works that their respective authors identified as historical ecology. I also examine the appearance and interconnectedness of the two main trends (ecological and anthropological) in historical ecological research. In the last part, I attempt to outline the future of historical ecology based on common features in existing research. It appears that at present historical ecology is at a crossroads. With rapidly growing interest in historical ecological research, it may move towards institutionalization or remain an umbrella term.

Summary The plant community structure of European lowland forests has changed dramatically in the twentieth century, leading to biodiversity decline at various spatial scales. However, due to methodological difficulties associated with simultaneous changes in species diversity and composition, ecological processes behind the changes are still poorly understood. We analysed temporal changes in forest plant community after the mid-twentieth-century abandonment of coppicing in a typical Central European forest, which had been managed as coppice for centuries. We used 122 semi-permanent plots first surveyed in the 1950s shortly after the last coppicing and again in the 2000s after half a century of natural succession. We used a novel temporal nestedness analysis to disentangle the immigration and extinction processes underlying temporal changes in community structure and tested whether species gains and losses were ecologically random. The studied vegetation has shifted from the species-rich assemblages of a relatively open and low-nutrient forest towards the impoverished flora of a closed-canopy forest dominated by a few shade-adapted species. The significant reduction in beta diversity, that is, compositional heterogeneity among plots, indicated taxonomic homogenization of the forest understorey. Temporal species turnover was only a minor component of the community change, and recent assemblages are nested subsets of the former ones. Ecologically non-random extinctions dominated these changes. Light-demanding species with a persistent seed bank were the most prone to extinction, while species with high specific leaf area substantially increased in frequency. Synthesis and applications. The dominant process after the abandonment of coppicing was the ecologically non-random extinction of light-demanding species, leading to an impoverished, temporally nested plant community structure. This development is typical for many abandoned coppices and poses a significant threat to forest biodiversity in Europe. If forestry and conservation policies continue to prefer closed-canopy stands, many endangered species are likely to pay their extinction debts. To restore declining or even locally extinct species, canopy opening in abandoned coppices is urgently needed.

The important role of humans in the development of current ecosystems was recognized decades ago; however, the integration of history and ecology in order to inform conservation has been difficult. We identified four issues that hinder historical ecological research and considered possible solutions. First, differences in concepts and methods between the fields of ecology and history are thought to be large. However, most differences stem from miscommunication between ecologists and historians and are less substantial than is usually assumed. Cooperation can be achieved by focusing on the features ecology and history have in common and through understanding and acceptance of differing points of view. Second, historical ecological research is often hampered by differences in spatial and temporal scales between ecology and history. We argue that historical ecological research can only be conducted at extents for which sources in both disciplines have comparable resolutions. Researchers must begin by clearly defining the relevant scales for the given purpose. Third, periods for which quantitative historical sources are not easily accessible (before AD 1800) have been neglected in historical ecological research. Because data from periods before 1800 are as relevant to the current state of ecosystems as more recent data, we suggest that historical ecologists actively seek out data from before 1800 and apply analytic methods commonly used in ecology to these data. Fourth, humans are not usually considered an intrinsic ecological factor in current ecological research. In our view, human societies should be acknowledged as integral parts of ecosystems and societal processes should be recognized as driving forces of ecosystem change. Resumen: El papel importante de los humanos en el desarrollo de los ecosistemas actuales fue reconocido hace decadas; sin embargo, la integracion de la historia y la ecologia para poder informar a la conservacion ha sido dificil. Identificamos 4 temas que limitan la investigacion ecologica historica y consideramos posibles soluciones. Primero, se piensa que las diferencias en conceptos y metodos entre campos de la ecologia y la historia son grandes. Sin embargo, la mayoria de las diferencias se derivan de la falta de comunicacion entre ecologos e historiadores y son menos sustanciales de los que generalmente se piensa. La cooperacion es posible mediante el enfoque en atributos que la ecologia y la historia tienen en comun y mediante el entendimiento y aceptacion de puntos de vista diferentes. Segundo, la investigacion ecologica historica a menudo es obstaculizada por diferencias en escalas espaciales y temporales entre la ecologia e historia. Argumentamos que la investigacion ecologica historica solo puede ser desarrollada en extensiones para las que fuentes en ambas disciplinas tienen resoluciones comparables. Los investigadores deben comenzar por definir claramente las escalas relevantes para el proposito determinado. Tercero, los periodos para los que no hay fuentes historicas cuantitativas facilmente accesibles (antes de 1800 AD) han sido desatendidos en la investigacion ecologica historica. Debido a que datos de periodos previos a 1800 son tan relevantes para el estado actual de los ecosistemas como los datos actuales, sugerimos a los ecologos historiadores que busquen datos previos a 1800 y les apliquen metodos analiticos utilizados comunmente. Cuarto, los humanos generalmente no son considerados un factor ecologico intrinseco en la investigacion ecologica en curso. Desde nuestra perspectiva, las sociedades humanas deben ser reconocidas como parte integral de los ecosistemas y los procesos sociales deben ser reconocidos como fuerzas conductoras del cambio en los ecosistemas.

We were glad to read Pooley’s (2013) comments on our earlier paper (Szabo & Hedl 2011) and welcome this opportunity to further discuss some important issues we could not elaborate on in that paper. Although we concur with Pooley on many points, let us start with a clarification. It may be generally true that “previous calls for cooperation between historians and conservation scientists published in ecological and conservation journals have been made by nonhistorians” (Pooley 2013), but it is certainly not true in our case. One of us is a historian with a PhD in medieval studies, the other is a vegetation ecologist. We believe our work benefited from fruitful discussions between two authors who saw the topic from often opposing perspectives. Nonetheless, we have our doubts whether disciplinary categorization is constructive when used as the basis for evaluating an individual researcher’s point of view.

Blends were prepared from a linear low density polyethylene and a polyisobutylene in the entire composition range. Flory-Huggins interaction parameters were determined from DMTA and DSC measurements. The usual technique had to be modified in the case of DSC data, since the Tg of PE cannot be determined by this technique. The two methods yielded identical results and indicated good interaction of the components, which was supported also by a SEM study and the mechanical properties of the blends.