Xerothermic grasslands of Pilica surroundings - diversity, threats and directions of changes

Xerothermic grasslands from three stands in the surroundings of the town of Pilica in the Kraków-Częstochowa Upland were investigated. It was ascertained that they represent two phytosociological units: Adonido-Brachypodietum (with two variants) and Silene otites-Thymus austriacus community. Moreover, phytocoenoses with a high contribution of xerothermic plants (Thymus-Anthyllis vulneraria community) were found in some places on the abandoned fields. On the basis of the comparison of new data and old phytosociological releves, only slight changes over 30 years were observed. The differences concerned mostly the coverage of particular species. However, some plants disappeared and other were new (e.g. seedlings of trees and shrubs). Generally, these species were not too frequent and had inconsiderable cover. The changes which occurred manifested themselves also in the differences of mean values of some ecological indicators and in the increase of competitors, as well as clonal species

Characteristics of the flora of fallow lands on rendzina soils on the Twardowice Plateau (Silesian Upland)

The paper presents the results of investigations on the flora of fallow lands on rendzina soils. The research was carried out in the area of the Twardowice Plateau (the Silesian Upland) within 9 areas adjacent to xerothermic grasslands. The investigated flora consisted of 220 vascular plant species with the dominance of native taxa. Plants of xerothermic grasslands and thermophilous edges were the most numerous (32%). The dominance of Libanotis pyrenaica in 4 of the examined areas should be emphasized. The percentage of meadow species was also considerable (25%). Anthropophytes comprised 18% of the flora of fallow lands and archaeophytes prevailed among them (9%). Solidago canadensis, an invasive species, was the constant component of the investigated fallows and sometimes its coverage was remarkable. As a result of the high proportion of xerothermic and thermophilous plants, plants associated with dry soils and soils having an intermediate character between dry and fresh, as well as plants preferring slightly acidic to alkaline soils poor in nitrogen compounds predominated in the investigated fallows. Perennial plants prevailed (65%) in the studied flora and slightly more than half of the species reproduced only by seeds. Competitive plant species (C strategists) had the highest proportion (39%) and species with intermediate strategies CSR, CR and CS were also numerous. The investigations have shown that there are favourable conditions for settling and growth of many xerothermic species in the investigated fallow lands. Moreover, the neighbouring grasslands are the seed source for these areas

Excavations of the Twardowice Plateau (Silesian Upland) as refuges for xerothermic plant species

Paper concerns the flora of excavations from the area of the Twardowice Plateau, one of the regions of the Silesian Upland. These are rather shallow and small pits, which are remnants of exploitation of Triassic limestone and, rarely, iron ore. The studies showed that these excavations are the places where many species of vascular plants occurred. Xerothermic plants, which penetrated from adjacent grasslands, form the largest group (33%) among the 212 noted species. Some of them occurred much more frequently in the excavations than in the grasslands and some were found only in the excavations. It should be emphasized that 8 protected species were present in the investigated objects. Results from the Twardowice Plateau proved that many xerothermic plants could find suitable conditions for growth and survival in limestone excavations

Characteristics of the flora of fallow lands on rendzina soils on the Twardowice Plateau (Silesian Upland)

The paper presents the results of investigations on the flora of fallow lands on rendzina soils. The research was carried out in the area of the Twardowice Plateau (the Silesian Upland) within 9 areas adjacent to xerothermic grasslands. The investigated flora consisted of 220 vascular plant species with the dominance of native taxa. Plants of xerothermic grasslands and thermophilous edges were the most numerous (32%). The dominance of Libanotis pyrenaica in 4 of the examined areas should be emphasized. The percentage of meadow species was also considerable (25%). Anthropophytes comprised 18% of the flora of fallow lands and archaeophytes prevailed among them (9%). Solidago canadensis, an invasive species, was the constant component of the investigated fallows and sometimes its coverage was remarkable. As a result of the high proportion of xerothermic and thermophilous plants, plants associated with dry soils and soils having an intermediate character between dry and fresh, as well as plants preferring slightly acidic to alkaline soils poor in nitrogen compounds predominated in the investigated fallows. Perennial plants prevailed (65%) in the studied flora and slightly more than half of the species reproduced only by seeds. Competitive plant species (C strategists) had the highest proportion (39%) and species with intermediate strategies CSR, CR and CS were also numerous. The investigations have shown that there are favourable conditions for settling and growth of many xerothermic species in the investigated fallow lands. Moreover, the neighbouring grasslands are the seed source for these areas

The emergence of new localities of Orobanche bartlingii Griseb. in the Silesian-Cracow Upland as a result of the spreading of Libanotis pyrenaica (L.) Bourgh. due to changes in land use : [poster]

During the last few decades, many cultivated fields and grazed grasslands have disappeared in the Silesian- Cracow Upland. Therefore, abandoned lands occupy now a large area there. As a result of these changes, some plant species have significantly increased the area of occurrence. Libanotis pyrenaica is one of them. In many places it begins to behave like an expansive species (Fragment tekstu)

Allergenic invasive plant Ambrosia artemisiifolia in Poland : threat and selected aspects of biology

The study presents the current state of research on Ambrosia artemisiifolia in Poland within its wider scientific background and gives the results of some field and laboratory investigations. This annual plant is characterised by a high level of production of seeds, easily dispersed by different vectors. Ragweed pollen is a strong allergen considered to be one of the most dangerous pollen allergens in the world. Being a serious hazard to human health, it is also considered as an Ñenvironmental weedî causing economic threat. The main aim of the study is to verify the status of the species in the flora of Poland, to assess the threat and discuss possibilities to prevent its future spread

A conceptual framework for prioritization of invasive alien species for management according to their impact

The number of invasive alien species is increasing and so are the impacts these species cause to the environment and economies. Nevertheless, resources for management are limited, which makes prioritization unavoidable. We present a prioritization framework which can be useful for decision makers as it includes both a scientific impact assessment and the evaluation of impact importance by affected stakeholders. The framework is divided into five steps, namely 1) stakeholder selection and weighting of stakeholder importance by the decision maker, 2) factual description and scoring of changes by scientists, 3) evaluation of the importance of impact categories by stakeholders, 4) calculation of weighted impact categories and 5) calculation of final impact score and decision making. The framework could be used at different scales and by different authorities. Furthermore, it would make the decision making process transparent and retraceable for all stakeholders and the general public.v2012o

Fewer non‐native insects in freshwater than in terrestrial habitats across continents

Aim Biological invasions are a major threat to biodiversity in aquatic and terrestrial habitats. Insects represent an important group of species in freshwater and terrestrial habitats, and they constitute a large proportion of non-native species. However, while many non-native insects are known from terrestrial ecosystems, they appear to be less represented in freshwater habitats. Comparisons between freshwater and terrestrial habitats of invader richness relative to native species richness are scarce, which hinders syntheses of invasion processes. Here, we used data from three regions on different continents to determine whether non-native insects are indeed under-represented in freshwater compared with terrestrial assemblages. Location Europe, North America, New Zealand. Methods We compiled a comprehensive inventory of native and non-native insect species established in freshwater and terrestrial habitats of the three study regions. We then contrasted the richness of non-native and native species among freshwater and terrestrial insects for all insect orders in each region. Using binomial regression, we analysed the proportions of non-native species in freshwater and terrestrial habitats. Marine insect species were excluded from our analysis, and insects in low-salinity brackish water were considered as freshwater insects. Results In most insect orders living in freshwater, non-native species were under-represented, while they were over-represented in a number of terrestrial orders. This pattern occurred in purely aquatic orders and in orders with both freshwater and terrestrial species. Overall, the proportion of non-native species was significantly lower in freshwater than in terrestrial species. Main conclusions Despite the numerical and ecological importance of insects among all non-native species, non-native insect species are surprisingly rare in freshwater habitats. This is consistent across the three investigated regions. We review hypotheses concerning species traits and invasion pathways that are most likely to explain these patterns. Our findings contribute to a growing appreciation of drivers and impacts of biological invasions

Ecological Impacts of Alien Species: Quantification, Scope, Caveats, and Recommendations

Despite intensive research during the past decade on the effects of alien species, invasion science still lacks the capacity to accurately predict the impacts of those species and, therefore, to provide timely advice to managers on where limited resources should be allocated. This capacity has been limited partly by the context-dependent nature of ecological impacts, research highly skewed toward certain taxa and habitat types, and the lack of standardized methods for detecting and quantifying impacts. We review different strategies, including specific experimental and observational approaches, for detecting and quantifying the ecological impacts of alien species. These include a four-way experimental plot design for comparing impact studies of different organisms. Furthermore, we identify hypothesis-driven parameters that should be measured at invaded sites to maximize insights into the nature of the impact. We also present strategies for recognizing high-impact species. Our recommendations provide a foundation for developing systematic quantitative measurements to allow comparisons of impacts across alien species, sites, and tim

Ecological impacts of alien species: quantification, scope, caveats, and recommendations

Despite intensive research during the past decade on the effects of alien species, invasion science still lacks the capacity to accurately predict the impacts of those species and, therefore, to provide timely advice to managers on where limited resources should be allocated. This capacity has been limited partly by the context-dependent nature of ecological impacts, research highly skewed toward certain taxa and habitat types, and the lack of standardized methods for detecting and quantifying impacts. We review different strategies, including specific experimental and observational approaches, for detecting and quantifying the ecological impacts of alien species. These include a four-way experimental plot design for comparing impact studies of different organisms. Furthermore, we identify hypothesis-driven parameters that should be measured at invaded sites to maximize insights into the nature of the impact. We also present strategies for recognizing high-impact species. Our recommendations provide a foundation for developing systematic quantitative measurements to allow comparisons of impacts across alien species, sites, and time