Popiela et al. (2015) Acta Botanica Gallica

Popiela A., Łysko A., Molnár V.A., Kącki Z., Lukács B. A.(2015): Elatine triandra Schkuhr (Elatinaceae) in Europe, with special emphasis on the central part of thecontinent. – Acta Botanica Gallica – Botany Letters 162 DOI:10.1080/12538078

Abstract

Elatine trianda Schkuhr is the most widespread species within the genus Elatine L.; it can be found in all continents, except Antarctica, but the majority of the locations have been recorded in Europe. The study is based on an extensive dataset of literature, herbaria and web data, which spans the period 1828–2012. The range of the species in Europe is disjunctive; it covers the southern and western parts of the Central European Plain and the northern shores of the Baltic Sea, it can also be found along some river valleys. In Central Europe many localities especially isolated ones in northern part of the range are historical now. According to the dataset we determined that E. triandra can be observed between May and October. We also found a remarkable historical decrease of observation time. We found that species observation has a near significant shift since 1828 that correlates to changes in environmental variables. Depending on the environmental conditions individuals of the taxon could develop in two forms: terrestrial and aquatic. The aquatic form is characterized by twice longer stems and internodes, and also almost twice longer lamina and petiola. E. triandra seeds show consistent characteristics both in terms of forms and populations. Our studies show that the best diagnostic feature, in addition to the construction of flowers, are size, shape and surface structure of seeds. In Central Europe E. triandra occurs exlusively in communities classified to the Isoëto-Nano-Juncetea, however the number of species characteristic for the class and lower syntax in patches decreases from north to south of the continent.

Keywords

chorology, ephemerophyte, Isoëto-Nano-Juncetea, phytogeography, vegetation, morphology, maps, phenology

Vadadi-Fülöp et al. (2012) Aquatic Ecology

Csaba Vadadi-Fülöp, Csaba Sipkay, Gergely Mészáros and Levente Hufnagel (2012): Climate change and freshwater zooplankton: what does it boil down to? Aquatic Ecology 46(4): 501-519. DOI: 10.1007/s10452-012-9418-8


Abstract
Recently, major advances in the climate-zooplankton interface have been made some of which appeared to receive much attention in a broader audience of ecologists as well. In contrast to the marine realm, however, we still lack a more holistic summary of recent knowledge in freshwater. We discuss climate change-related variation in physical and biological attributes of lakes and running waters, high-order ecological functions, and subsequent alteration in zooplankton abundance, phenology, distribution, body size, community structure, life history parameters, and behavior by focusing on community level responses. The adequacy of large-scale climatic indices in ecology has received considerable support and provided a framework for the interpretation of community and species level responses in freshwater zooplankton. Modeling perspectives deserve particular consideration, since this promising stream of ecology is of particular applicability in climate change research owing to the inherently predictive nature of this field. In the future, ecologists should expand their research on species beyond daphnids, should address questions as to how different intrinsic and extrinsic drivers interact, should move beyond correlative approaches toward more mechanistic explanations, and last but not least, should facilitate transfer of biological data both across space and time.


Keywords
Global warming, Daphnia, Phenology, Community dynamics, Ecological models

Somodi et al. (2012) Biological Conservation

Imelda Somodi, Andraž Čarni, Daniela Ribeiro, Tomaž Podobnikar (2012): Recognition of the invasive species Robinia pseudacacia from combined remote sensing and GIS sources. Biological Conservation, 150 (1) 59–67. DOI 10.1016/j.biocon.2012.02.014


Abstract
Monitoring the spread of invasive species is crucial for nature conservation; however regularity can only be assured if cost-effectiveness can be achieved. We aimed at testing low-cost remote sensing sources and simple methodology for recognising the invasive species Robinia pseudacacia and thus founding a monitoring scheme. A study area with mixed wooded stands containing R. pseudacacia has been selected for this purpose in NE Slovenia. Four different sources (Landsat ETM and airborne orthophotos from summer and spring) were tested together with a filtering for forested areas. Filtering was based either on Landsat information or on a forest polygon layer as alternatives. Generalised linear models were constructed in a training window within the study area to establish a statistical rule of recognition for the species based on spectral information. Models were tested both within and outside the training window for accuracy. As means of accuracy assessment both the well-established AUC and the specially adapted Jaccard index have been applied.
The best and most reliable recognition was achieved by using the spring orthophoto, in which the species was captured in flower, combined with a GIS filtering by a forest vector layer. The superiority of this combination was especially striking when tested over the full study area. The Jaccard index appeared to be more sensitive in discrimination between models. Thus we conclude that even spectrally less detailed data sources may provide a basis for successful monitoring if the phenology of the target species is also considered.


Keywords
AUC, Cost-effectiveness, GLM, Landsat, Orthophoto, Phenology