Response of Cladocera Fauna to Heavy Metal Pollution, Based on Sediments from Subsidence Ponds Downstream of a Mine Discharge (S. Poland)

Mining is recognized to deeply influence invertebrate assemblages in aquatic systems, but di erent invertebrates respond in di erent ways to mining cessation. Here, we document the response of the cladoceran assemblage of the Chechło river, S. Poland (southern Poland) to the cessation of Pb-Zn ore mining. The aquatic system includes the river and associated subsidence ponds in the valley. Some ponds were contaminated during the period of mining, which ceased in 2009, while one of the ponds only appeared after mining had stopped. We used Cladocera to reveal how the cessation of mine water discharge reflected on the structure and density of organisms. A total of 20 Cladocera taxa were identified in the sediment of subsidence ponds. Their density ranged from 0 to 109 ind./1 cm3. The concentrations of Zn, Cd, Cu and Pb were much higher in sediments of the ponds formed during peak mining than in the ponds formed after the closure of the mine. Statistical analysis (CCA) showed that Alonella nana, Alona a nis, Alona sp. and Pleuroxus sp. strongly correlated with pond age and did not tolerate high concentrations of heavy metals (Cu and Cd). This analysis indicated that the rate of water exchange by the river flow and the presence of aquatic plants, a ect species composition more than pond age itself

Neo- and Paleo-Limnological Studies on Diatom and Cladoceran Communities of Subsidence Ponds Affected by Mine Waters (S. Poland)

Plankton assemblages can be altered to di erent degrees by mining. Here, we test how diatoms and cladocerans in ponds along a river in southern Poland respond to the cessation of the long-term Pb-Zn mining. There are two groups of subsidence ponds in the river valley. One of them (DOWN) was contaminated over a period of mining, which ceased in 2009, whereas the other (UP) appeared after the mining had stopped. We used diatoms and cladocerans (complete organisms in plankton and their remains in sediments) to reveal the influence of environmental change on the structure and density of organisms. The water of UP pond was more contaminated by major ions (SO4 2, Cl) and nutrients (NO3 , PO4 3) than the DOWN ponds. Inversely, concentrations of Zn, Cd, Cu and Pb were significantly higher in sediment cores of DOWN ponds in comparison to those in the UP pond. Ponds during mining had higher diversity of diatoms and cladocerans than the pond formed after the mining had stopped. CCA showed that diatom and cladoceran communities related most significantly to concentrations of Pb in sediment cores. Comparison of diatom and cladoceran communities in plankton and sediment suggests significant recovery of assemblages in recent years and reduction of the harmful e ect of mine-originating heavy metals. Some features of ponds such as the rate of water exchange by river flow and the presence of water plants influenced plankton communities more than the content of dissolved heavy metals

Influence of Selected Environmental Factors on Diatom β Diversity (Bacillariophyta) and the Value of Diatom Indices and Sampling Issues

Human impacts and environmental climate changes have led to a progressive decline in the diversity of diatoms in lakes in the recent past. The components of β diversity (e.g., species turnover and nestedness) and underlying factors are still poorly understood. Here, we report an investigation of two alternative approaches—beta diversity (β diversity) partitioning and local contribution to β diversity (LCBD)—including their responses to selected environmental factors and representativeness of samples in estimating the ecological fitness of a lake. The β diversity of diatoms and their local contributions could be explained by the effects of environmental variables (p < 0.01). The random forest method showed the most contribution to the variance for NO3−, Cl−, and SO42−. PERMANOVA as well as a network analysis in JASP (Jeffrey’s Amazing Statistics Program) showed significant differences between the seasons in diatom assemblages and in the diatom index for Polish lakes (IOJ). Our findings provide insights into the mechanisms responsible for community organizations along environmental gradients from the perspective of β diversity components, and mechanisms of the indication value of diatoms for lakes; the results could be used especially by countries implementing ecological assessments

Influence of Selected Environmental Factors on Diatom β Diversity (Bacillariophyta) and the Value of Diatom Indices and Sampling Issues

Human impacts and environmental climate changes have led to a progressive decline in the diversity of diatoms in lakes in the recent past. The components of β diversity (e.g., species turnover and nestedness) and underlying factors are still poorly understood. Here, we report an investigation of two alternative approaches—beta diversity (β diversity) partitioning and local contribution to β diversity (LCBD)—including their responses to selected environmental factors and representativeness of samples in estimating the ecological fitness of a lake. The β diversity of diatoms and their local contributions could be explained by the effects of environmental variables (p 3−, Cl−, and SO42−. PERMANOVA as well as a network analysis in JASP (Jeffrey’s Amazing Statistics Program) showed significant differences between the seasons in diatom assemblages and in the diatom index for Polish lakes (IOJ). Our findings provide insights into the mechanisms responsible for community organizations along environmental gradients from the perspective of β diversity components, and mechanisms of the indication value of diatoms for lakes; the results could be used especially by countries implementing ecological assessments

Spatial Patterns in the Distribution and Diversity of <i>Diploneis</i> Genus-Level Diatoms in the Podlasie Springs (North-Eastern Poland)

This research is focused on the presence of the genus Diploneis (Bacillariopyta) in small lowland springs of north-eastern Poland. This study presents a biogeographic overview of the genus from 2 urban and 12 forest springs in the Podlasie area. Seven species were identified, some of which have been described recently and whose distribution is not well-known (D. burgitensis, D. fontium). The presence of D. burgitensis and D. parapetersenii, both rare taxa, are the first recorded for Poland. Their presence was confirmed using both LM and SEM micrographs. The presence of much more frequently noted European species (D. elliptica, D. fontanella, D. krammeri, and D. separanda) was also found. Greater knowledge of the Diploneis genus opens the way towards better and more comprehensive approaches to uncovering biological diversity and biogeographical patterns on the European continent and among the springs. The distribution of all recorded Diploneis species and their habitat preferences are briefly given

Revision of **Navicula striolata** (Grunow) Lange-Bertalot and N. rumaniensis Hustedt with the description of N. **friedelhinziae** sp nov.

Navicula striolata was originally described as N. digitoradiata var. striolata from modern material collected in Sweden. After examination of a sample collected from Belgium, the variety was transferred to N. reinhardtii as N. reinhardti var. gracilior. From this time a large mix up of these and related taxa was observed in the literature. A similar species, Navicula rumaniensis had also been established in 1934 from Neogene Romanian materials but there has been much confusion regarding the status of these taxa, leading to a poor understanding of their distribution. In this study, type material of Navicula digitoradiata var. striolata, N. reinhardtii var. gracilior and N. rumaniensis are revised using light and scanning electron microscopy in order to clarify their identity and to investigate possible conspecificity. The results indicate that these species are not synonyms. Conspecificity of the modern N. digitoradiata var. striolata and N. reinhardti var. gracilior was confirmed and lectotypes of both varieties have been designated whereas N. rumaniensis proved to be a separate species. In addition, the study of Neogene material from Bulgaria revealed the presence of a new Navicula taxon—N. friedelhinziae. The morphology of these and similar taxa is discussed