Marcin Kiedrzyński

Sustainable floodplain management for flood prevention and water quality improvement

Although it is not possible to completely eliminate flooding in an era of climate change and intensification of extreme weather events, effective flood prevention and management in river floodplains may make a significant contribution. The land use characteristics of a catchment and river valley determine, to a great extent, the functioning of a river floodplain, as well as the quantity and size of the flood pulses in the river. The paper is focused on the role played by ecohydrology in flood risk management and water quality. From the ecohydrological perspective, river floodplains are extremely important and capacious ecosystems which, being periodically flooded, absorb flood and pollutant peaks and may minimise the danger of flooding. Increased natural water retention capacity in floodplain areas and the whole basin in the face of progressive climate change is possible through three routes: the modelling of the hydrological budget of the catchment towards the sustainable ecohydrological management of floodplains, the optimal use of existing hydrotechnical infrastructure and the implementation of ecohydrological biotechnologies. Furthermore, with such a holistic perspective, the role of river floodplains is one that also enhances the resilience of the river basin against climate and anthropogenic change, as well as increasing flood safety, improving water quality and increasing its ecosystem services for society.

Regional climate and geology affecting habitat availability for a relict plant in a plain landscape: the case of Festuca amethystina L. in Poland

Background: The distribution of refugial habitats is the main factor affecting the existence of cold-adapted species in the lowlands. In addition, regional climatic conditions could have an influence on relicts. Aims: Co-occurrence of environmental factors in the determination of the distribution of the glacial relict Festuca amethystina was examined in Poland. Methods: Climatic data, habitat indicator species, parent material of soils and range of glaciations were analysed, using ecological niche modelling. Prediction of Festuca amethystina occurrence for different sets of data – only climatic, only habitat and all data – was modelled. Results: The distribution of Festuca amethystina was related to the presence of oak forests (Potentillo albae-Quercetum), to moderate subcontinental climate, but not to the distribution of loess soils. In addition, variables related to temperature and precipitation in the driest quarter of the year, isothermality and a mean diurnal range had the strongest influence on the occurrence of F. amethystina within the Potentillo-Quercetum range. Conclusions: Climate acts as a regional filter and habitat availability as a local filter for distribution of the species. Therefore, the habitat can act as microrefugium in some parts of its range. In a flat landscape, relicts can persist where environmental conditions are simultaneously favourable for the persistence of refugial vegetation and relict populations.

The relationship between climatic conditions and generative reproduction of a lowland population of Pulsatilla vernalis: the last breath of a relict plant or a fluctuating cycle of regeneration?

The alpine-boreal plants which have survived in Central European lowlands during glacial periods depend both on the preservation of their refugial habitat, and their capability for vegetative and generative reproduction and dispersion. Pulsatilla vernalis (L.) Mill. is a model species which occurs throughout most of the European alpine system, as well as in isolated populations in the lowlands. At present, the relict lowland localities of this species often have a historic character. In the Polish lowlands, only the population located in Rogowiec is characterized by effective recruitment. It presents a large number of rosettes and a diversified demographic structure, with plants in all stages of development. The study examines the population in Rogowiec from 2002 to 2008 with regard to the number of flowering and fruiting shoots, new seedlings, and loss of juvenile rosettes, and the obtained data are correlated with climatic conditions. Three years were found to demonstrate effective recruitment, with numerous seedlings and little loss of juvenile rosettes. No significant relationship was found between seedling dynamics and the flowering–fruiting process. However, correlations were found between effective renewal and some climatic factors. Temperature, water balance, and solar radiation were found to have a limiting effect on the reproduction and regeneration of the analyzed relict population. Due to the longevity of the rosettes, favorable climatic conditions occurring every few years are sufficient for survival of the species in this location. However, serious threats are posed by the climate change trends expected in Europe over the coming decades, and the fact that due to its small-scale dispersal ability, the analyzed species occupies only a small area in Rogowiec.

Hierarchy of factors exerting an impact on nutrient load of the Baltic Sea and sustainable management of its drainage basin

The aim of the paper was to evaluate 23 catchment factors that determine total phosphorus and total nitrogen load to the Baltic Sea. Standard correlation analysis and clustering were used. Both phosphorus and nitrogen loads were found to be positively related to the number of pigs and the human population associated with wastewater treatment plants (WWTPs) per km(2), while the number of cattle and agricultural area were found to influence nitrogen rather than phosphorus load, and the area of forests is negatively related to loads of both nutrients. Clustering indicates an overall north-south pattern in the spatial co-occurrence of socio-ecological factors, with some exceptions discussed in the paper. Positive steps in the Baltic Sea region have already been taken, but much remains to be done. The development of coherent response policies to reduce eutrophication in the Baltic Sea should be based on a comprehensive knowledge base, an appropriate information strategy and learning alliance platform in each drainage river catchments.

CHANGING LAND USE IN RECENT DECADES AND ITS IMPACT ON PLANT COVER IN AGRICULTURAL AND FOREST LANDSCAPES IN POLAND

Changing Land Use in Recent Decades and its Impact on Plant Cover in Agricultural and Forest Landscapes in Poland The objective of this paper is to present the effects of general changes in land use in recent decades on plant cover structure in Poland. The paper is focused on spontaneous processes that occur in agricultural and forest areas being no longer under human pressure. Studies carried out in different geobotanical regions of Poland demonstrated that the directions and range of dynamic changes in plant cover are similar across the country. The formation of secondary forest phytocenoses, on the lands delivered from human activity is a common ecological process observed today in the agricultural landscape. In the dynamics of forest vegetation the basic process is regeneration after ceased use, and the introduction of legal protection.

Forest roadsides harbour less competitive habitats for a relict mountain plant ( Pulsatilla vernalis ) in lowlands

The long-term survival of relict populations depends on the accessibility of appropriate sites (microrefugia). In recent times, due to the mass extinction of rare species that has resulted from the loss of natural habitats, the question is – Are there any human-made sites that can act as refugial habitats? We examined forest roadside populations of the mountain plant Pulsatilla vernalis in the last large lowland refugium in Central Europe. We compared the habitat conditions and community structure of roadsides with P. vernalis against the forest interior. Light availability and bryophyte composition were the main factors that distinguished roadsides. Pulsatilla occurred on sites that had more light than the forest interior, but were also more or less shaded by trees, so more light came as one-side illumination from the road. Roadsides had also a lower coverage of bryophytes that formed large, dense carpets. At the same time, they were characterised by a greater richness of vascular plants and ‘small’ bryophytes, which corresponds to a higher frequency of disturbances. In a warming and more fertile Anthropocene world, competition plays the main role in the transformation of forest communities, which is why relict populations have found refugia in extensively disturbed human-made habitats.

TRANSFORMATION OF FOREST VEGETATION AFTER 40 YEARS OF PROTECTION IN THE TOMCZYCE NATURE RESERVE (CENTRAL POLAND)

Transformation of Forest Vegetation After 40 Years of Protection in the Tomczyce Nature Reserve (Central Poland) The Tomczyce nature reserve is characterized by a degenerated forest vegetation. We assume that the regeneration process was possible to launch after the establishment of the nature reserve in 1968. The vegetation of the Tomczyce forest complex was characterized for the first time by Jakubowska-Gabara (1976) whose studies were taken as a basis of our research. The phytocenoses after 40. years of protection have a greater participation of species with higher trophic and moisture requirements. The regeneration process in communities with pine trees is caused by an expansion of broad-leaved trees and shrubs. Transformation of forest vegetation causes a decrease in cover of thermophilous and heliophilous species. On the other hand, species of oak-hornbeam forests as well as anthropophytes are in expansion. Planning of the protection activities in the nature reserve needs to include these dynamic tendencies of the vegetation.

Habitat and spatial thinning improve the Maxent models performed with incomplete data

Species distribution models need adequate sets of data, particularly in the case of range-restricted species. The problem faced in the modeling of rare species is twofold: a small sample size and the occurrence of sampling biases. The present analysis combines spatial- and habitat-thinning approaches to improve maximum entropy models based on geographically incomplete data of relict and subendemic Festuca amethystina L. grass on Polish territory. The results show that models based on strongly incomplete historic data did not predict the occurrence of all important areas where the species was found in the following decades. However, the introduction of species-specific thinning allows for more precise prediction of the species range, i.e., the detection of suitable areas on a more local scale. The introduction of habitat thinning caused the diversity of important predictors in model to increase, but spatial thinning decreased the number of significant predictors and made interpretation easier. Additionally, a combination of thinning techniques allowed significant improvements to be made to the model predictions after the experimental addition of a lower number of localities to regions which had previously been poorly recognized. It can be concluded that in the case of incomplete data, the above corrections allow the true range of the species to be predicted after the discovery of a lower number and relatively dispersed new localities.

Refugial debate: on small sites according to their function and capacity

The occurrence and location of long-term refugia determine the current patterns of biodiversity on Earth. The importance of the refugial debate is certain to increase in response to observed and expected species extinctions caused by climate change. Small areas where species survive outside their core range are important, as unique natural phenomena and model systems for observing the response of species to climate change. They can play a crucial role as potential sources for species recovery in the future or can act as progenitors of a new species. While most authors believe that sites connected with only long-term isolation should be included into the refugium concept, this approach can result in the loss of linkage between the ecological and evolutionary processes taking place during different phases of the species range dynamics. Moreover, the papers often interpret the nature of described phenomena in different ways. In response, the conceptual scheme given in our letter summarises the patterns which occur during species range shift. It proposes an equivalent scheme for small refugial sites according to their function and capacity, based on the relict species concept. This approach and proposed terminology is tested on the example of two plant species with different pattern of the long term range dynamics. Our paper highlights the importance of sites harboring ‘trailing-edge’ young relicts for the future long-term persistence of the species (as old relicts) under unfavorable regional conditions. By considering the age gradients of small refugial sites it is possible to reveal community interactions, species traits or genes that drive the responses of biota to climate changes.

The Role of Hydrology in the Polychlorinated Dibenzo--dioxin and Dibenzofuran Distributions in a Lowland River

Persistent organic pollutants such as polychlorinated dibenzo--dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are environmental contaminants that have widespread distribution and pose a serious threat to aquatic ecosystems. We conducted a study to quantify the distribution, patterns, and transport of PCDDs and PCDFs along the Pilica River in central Poland under different hydrological conditions to estimate the loads of these compounds and understand their fate in aquatic systems. Water samples were collected at five sampling points along the river that represent a range of hydrological conditions including flooding and stable and low water flows. Reduced river water flow was associated with lower average total and toxic equivalent (TEQ) concentrations of PCDDs plus PCDFs: 33.6 pg L and 4.21 pg TEQ L for flooding; 28.3 pg L and 3.6 pg TEQ L for stable flow; 18.4 pg L and 1.0 pg TEQ L for low-water flow. Similar results were observed for daily loadings of total and TEQ concentrations: the highest values were observed during flooding (331.1-839.4 mg d and 27.8-110.7 mg TEQ d), medium under stable hydrological conditions (55.8-121.0 mg d and 7.7-15.3 mg TEQ d), and the lowest values during low water flow (30.9 and 40.3 mg d and 1.4-2.4 mg TEQ d). The results demonstrate that diffuse sources of pollution play a key role during periods of high water flow (i.e., flooding season), whereas point sources of pollution, including municipal and industrial wastewater treatment plant discharges, mainly determine the PCDD and PCDF concentrations seen during low water periods.