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showing 10 items of 4660 documents
Breeding success of the Great Tit Parus major in relation to attributes of natural nest cavities in a primeval forest
2015
An overlap in attributes of nest cavities used by Great Tit Parus major across Eurasia suggests similar nest site preferences within the geographical range, although the drivers of these preferences are unclear. To determine whether preferred cavities provide conditions enhancing successful reproduction, we investigated the breeding performance of Great Tits in relation to tree cavity characteristics using data collected during 2008–2011 in primeval conditions (Białowieża National Park, Poland). Here, tree cavities are diverse and superabundant but nesting birds are at risk from a variety of predators. According to expectations, nest losses were high (60 % of Great Tit nests failed), mostly…
Impact of drainage and hydrological restoration on vegetation structure in boreal spruce swamp forests
2014
Drainage to increase timber production is a major cause of degradation of boreal peatlands in Europe. As a consequence of the forestry drainage, the area of pristine spruce swamp forests has declined drastically in northern Europe over the past century. In restoration by rewetting, drainage ditches are blocked to restore the pre-disturbance hydrological regime and, ultimately, the biodiversity values and ecosystem functions of pristine spruce swamp forests. In this study, we quantify vegetation recovery and examine mechanisms behind the changes in plant community composition. For this, we surveyed the understorey vegetation of 9 undrained, 9 drained and 18 rewetted spruce swamp forest sites…
A multi-proxy long-term ecological investigation into the development of a late Holocene calcareous spring-fed fen ecosystem (Raganu Mire) and boreal…
2021
Abstract The calcareous substrate of spring-fed fens makes them unique islands of biodiversity, hosting endangered, vulnerable, and protected vascular plants. Hence, spring-fed fens ecosystems require special conservation attention because many of them are destroyed (e.g. drained, forested) and it is extremely difficult or even impossible to restore the unique hydrogeological and geochemical conditions enabling their function. The long-term perspective of paleoecological studies allows indication of former wetland ecosystem states and provides understanding of their development over millennia. To examine the late Holocene dynamics of a calcareous spring-fed fen (Raganu Mire) ecosystem on th…
Immense plasticity of timing of breeding in a sedentary forest passerine, Poecile palustris
2015
Numerous bird species have advanced their breeding seasons in response to climate warming. These changes were mostly brought about by phenotypic plasticity, i.e. flexible reactions of individual birds, rather than by microevolutionary change. Knowing the limits of plasticity is thus of paramount importance in any attempt to predict possible reactions of birds to climate warming. However, the breeding performance of the same individuals in contrasting environmental conditions, necessary to answer this question, is rarely observed. Here, we provide data on the flexibility in timing of egg-laying of individual marsh tit Poecile palustris females breeding in an extremely late (2013) and early (…
New national and regional bryophyte records, 63
2020
Erkul, Karaman ( Aksaray, Yazar )
“Into and Out of” the Qinghai‐Tibet Plateau and the Himalayas: Centers of origin and diversification across five clades of Eurasian montane and alpin…
2020
Abstract Encompassing some of the major hotspots of biodiversity on Earth, large mountain systems have long held the attention of evolutionary biologists. The region of the Qinghai‐Tibet Plateau (QTP) is considered a biogeographic source for multiple colonization events into adjacent areas including the northern Palearctic. The faunal exchange between the QTP and adjacent regions could thus represent a one‐way street (“out of” the QTP). However, immigration into the QTP region has so far received only little attention, despite its potential to shape faunal and floral communities of the QTP. In this study, we investigated centers of origin and dispersal routes between the QTP, its forested m…
Spatial distribution, contamination assessment and potential ecological risk of some trace metals in the surface sediments of the Gulf of Tunis, Nort…
2021
To evaluate the trace metals contamination status in the Gulf of Tunis, forty one sediment samples were analyzed using different approaches. According to certain contamination and ecological risk indices (Contamination Factor, Geoaccumulation index and Ecological risk index), Hg has the highest contamination level while pollution by Ni, Pb, Cd and Cr was absent. The highest concentrations of trace metals were found in sediments collected from the offshore and coastal areas located opposite the main exchange points with the gulf particularly, the Mejerda and Meliane Rivers, the Khalij Channel, Ghar El Melh and El Malah lagoons, Tunis Lake and Sebkhat Ariana. However, further ecological indic…
The buffer effect of canopy-forming algae on vermetid reefs' functioning: A multiple stressor case study.
2021
Abstract Biodiversity plays a key role for our planet by buffering ongoing and future changes in environmental conditions. We tested if canopy-forming algae enhancing biodiversity (CEB) in a Mediterranean intertidal reef ecological community could alleviate the effect of stressors (heat waves and pollution from sewage) on community metabolic rates (as expressed by oxygen consumption) used as a proxy of community functioning. CEB exerted a buffering effect related to the properties of stressor: physical-pulsing (heat wave) and chronic-trophic (sewage). After a simulated heat wave, CEB was effective in buffering the impacts of detrimental temperatures on the functioning of the community. In r…
Do invasive alien plants really threaten river bank vegetation? : a case study based on plant communities typical for Chenopodium ficifolium : an ind…
2018
Riparian zones are very rich in species but subjected to strong anthropogenic changes and extremely prone to alien plant invasions, which are considered to be a serious threat to biodiversity. Our aim was to determine the spatial distribution of Chenopodium ficifolium, a species demonstrating strong confinement to large river valleys in Central Europe and an indicator of annual pioneer nitrophilous vegetation developing on river banks, which are considered to be of importance to the European Community. Additionally, the habitat preferences of the species were analysed. Differences in the richness and abundance of species diagnostic for riverside habitats, as well as the contribution of resi…
The first confirmed population of the globally endangered Pilularia minuta (Marsileaceae) in Sicily
2016
Based on a recent collection made by the authors, the presence of the endangered Pilularia minuta Durieu in Sicily (Italy) is confirmed. Critical review of relevant literature and herbarium specimens suggests that the only previous report for the island, made in 1887, can, fairly confidently, be considered to be the result of a misidentification. There is an urgent need to protect the wetland at Anguillara (near Calatafimi), where the species was found.