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The autumn stage of the Nationally vulnerable gelechiid moth Monochroa conspersella (H.-S., 1854) is described and illustrated. [ABSTRACT FROM AUTHOR]

Lobelia dortmanna L. (Lobeliaceae family) is an indicator species that is predominantly found in oligotrophic and acidic lakes. They are mainly distributed in northwestern Europe. Their occurrence in Poland is highly threatened by the increasing grade of human activity and environmental eutrophication; however, new sites of Lobelia were discovered in the last few decades, for example, in Lake Krzywce Wielkie situated in Bory Tucholskie National Park (BTNP), Poland. The existence of Lobelia in this lake was unexpected because Cladium mariscus was also found in the lake. Cladium has different ecological demands and is regarded as a species typical of calcareous habitats where calcium is found in abundance in the substrate. To explain the coexistence of both species in Krzywce Wielkie, pollen analysis of organic sediments was performed for four short cores collected from the littoral zone of the lake and for one long deep-water core. Additionally, macrofossil analysis was done for all the short cores. Pollen analysis revealed the existence of Cladium from the early Holocene period up to the present time. Pollen and seeds of Lobelia were found to be present since the beginning of the 20th century. Development of L. dortmanna and Myriophyllum alterniflorum populations and a decrease in the number of aquatic macrophytes in the eutrophic water indicate oligotrophication of water. This process started following the construction of drainage canal and the consequent water level decrease. This situation can be attributed to the abandonment of the agricultural areas adjoining the lake, which causes a decrease in the inflow of nutrients into the lake. Development of pine forest and establishment of BTNP enabled the protection and conservation of the surrounding catchment areas, thus restricting the potential eutrophication of the habitats.

Lobelia dortmanna L. (Lobeliaceae family) is an indicator species that is predominantly found in oligotrophic and acidic lakes. They are mainly distributed in northwestern Europe. Their occurrence in Poland is highly threatened by the increasing grade of human activity and environmental eutrophication; however, new sites of Lobelia were discovered in the last few decades, for example, in Lake Krzywce Wielkie situated in Bory Tucholskie National Park (BTNP), Poland. The existence of Lobelia in this lake was unexpected because Cladium mariscus was also found in the lake. Cladium has different ecological demands and is regarded as a species typical of calcareous habitats where calcium is found in abundance in the substrate. To explain the coexistence of both species in Krzywce Wielkie, pollen analysis of organic sediments was performed for four short cores collected from the littoral zone of the lake and for one long deep-water core. Additionally, macrofossil analysis was done for all the short cores. Pollen analysis revealed the existence of Cladium from the early Holocene period up to the present time. Pollen and seeds of Lobelia were found to be present since the beginning of the 20th century. Development of L. dortmanna and Myriophyllum alterniflorum populations and a decrease in the number of aquatic macrophytes in the eutrophic water indicate oligotrophication of water. This process started following the construction of drainage canal and the consequent water level decrease. This situation can be attributed to the abandonment of the agricultural areas adjoining the lake, which causes a decrease in the inflow of nutrients into the lake. Development of pine forest and establishment of BTNP enabled the protection and conservation of the surrounding catchment areas, thus restricting the potential eutrophication of the habitats. [ABSTRACT FROM AUTHOR]

This study presents the palaeo-botanical record from the central part of Žitný Ostrov Island on the Danubian Lowland in Slovakia. The record spans almost the entire Holocene period and provides evidence that the wetland species Cladium mariscus (Cyperaceae) was present in this region as late as the Greenlandian period. In addition, the combination of C. mariscus and Carex elata beds were most likely an important part of the littoral zone vegetation during that period. Our investigations are based on plant macro-remain analysis, radiocarbon dating and physical sedimentary analysis of the former Danube side channel. The palaeo-channel infill active in the Late Pleistocene reflects complete hydroseral succession of a terrestrialised palaeo-lake. The earlier of two possible hiatuses in the fossil record was likely associated with a disturbance which caused Cladium mariscus to disappear from the local plant spectra. The most likely drivers of C. mariscus' decline are a climate change of 8.6 cal ka BP associated with water fluctuations and the local habitat alteration to an eutrophic environment. These are discussed herein together with the isolated scattered populations surviving in the surrounding micro-region throughout the Meghalayan period. Finally, there are only two known remaining C. mariscus sites in the Žitný Ostrov Island area, and the key modern driving factor was the dramatic water regime changes in 19–20th Century caused by anthropogenic impact. These were caused by the construction of drainage canal systems and the transition from alluvial meadows to agricultural land. [ABSTRACT FROM AUTHOR]

Este trabajo presenta los cambios en la extensión de las superficies ocupadas por las praderas sumergidas de carófitos y por las formaciones emergentes de masiega en el humedal del Parque Nacional Las Tablas de Daimiel (Ciudad Real, España). Se estudian las dinámicas de ocupación desde los años cincuenta hasta la actualidad, y se relacionan con las perturbaciones más relevantes como sequía, incendios y contaminación. Se destaca el papel de estos dos componentes del ecosistema acuático como indicadores de la calidad ambiental de esta zona húmeda continental.

We document the long-term development of a spring-fed fen assessing its sensivity to climate changes over the last ca. 4000 years. Our investigation is based on high-resolution, continuous plant macrofossil remains and mollusc records, complemented by pollen, geochemical analysis and radiocarbon dating of Valea Morii, located in the Feleac Hills (Transylvanian Depression) in NW Romania, Central Eastern Europe. Based on our palaeocological data we have distinguished three stages of wet habitat conditions: two stages between 4000 and 2450 cal yr BP and one in the last 800 cal yr BP, and one dry stage between ca. 2450 and 800 cal yr BP. These local habitat conditions appear to reasonably reflect regional climate characteristics. High-resolution analysis of two replicated cores documented a mostly comparable pattern of local plant and mollusc succession, and stable isotope values from ca. 500 cal yr BP. The appearance of C . mariscus during the last two centuries may be related to increased wetness and associated active CaCO 3 precipitation, which allowed this plant to colonise the spring-fed fen studied. However, it can be not excluded that the occurrence and spread of a Cladium mariscus population at this site during the last two centuries might have been partly favoured by the warming of the climate after the Little Ice Age. The potential of carbonate oxygen stable isotope values as an indicator of major trends in climatic change, both temperature and humidity, in mountain spring-fed fen deposits is shown. Carbon isotopes in the carbonates were found to be useful in reconstruction of changes in vegetation, soil development and the dissolution of bedrock carbonates, primarily as a reaction to changes in climate humidity. [ABSTRACT FROM AUTHOR]

Copyright of Journal of College of Education for Pure Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Here, for the first time in SE Poland, we document the long-term development of a rich fen and assess its sensitivity to climate change and human impacts over the last ca. 3500 years. Our results are based on a high-resolution, continuous plant macrofossil remains, mollusc and pollen record, complemented by geochemical, mineral magnetic and physical characterisation, and radiocarbon dating from Bagno Serebryskie rich fen located in SE Poland. Based on the palaeoecological data we distinguished five stages of wet habitat conditions: 5000–3300, 2800–2150, 1600–1100, 750–230, 150–10 cal yr BP and five dry periods at ca. 3300–2800, 2150–1600, 1100–750, 230–150, 10 to − 64 cal yr BP. The pollen and geochemistry records, particularly Pb, show that the first human activity in the study area occurred ca. 3200 cal yr BP and increased markedly from 500 cal yr BP affecting local plant development including the population size of Cladium mariscus . Our study has shown that despite human impact (drainage, fire), Bagno Serebryskie peatland has hosted rare, presently protected species, such as Cladium mariscus for hundreds of years. We conclude that, in common with ombrotrophic bogs, rich fen ecosystems can provide a reliable source of palaeoclimatic and palaeohydrological data. Our study also shows that a large peatland (376 ha) can be as sensitive a palaeohydrological archive as smaller mires. [ABSTRACT FROM AUTHOR]

This paper presents the results of 11 years study of aquatic warblers in the Roskosz Nature Reserve in eastern Poland. The study was carried out in fen mires near Chełm, in the proximity of the Polish-Ukrainian boundary. The number of aquatic warblers was correlated with the mean water level and with the mean groundwater level. We found that the higher the surface water level, the smaller the number of singing males. The largest number of males (density 10.9 singing males per 10 ha) was found when the mean water level was 23.7 cm, and the smallest number (density 2.1 singing males per 10 ha) when the mean water level was 35.7 cm. These results can be useful in studies that focus on the optimal habitat conditions for breeding of aquatic warblers. This is the first systematic study in calcareous Cladium mariscus fen mires. [ABSTRACT FROM AUTHOR]

Effective conservation of priority habitat 7210* Calcareous fens with Cladium mariscus and species of the Caricion davallianae depends on complete knowledge of the biology of Cladium mariscus. This study was aimed to determine effect of temperature and habitat water level on growth, development and physiological status of generative shoots of C. mariscus. Maximum quantum yield of photosystem II photochemistry dynamics during both seasons was similar; but in summer 2016 the values were significantly higher than in 2015. Difference in height of generative shoots was not found between years. Average number of generative shoots indicated a significant difference between years. Immediate effect of temperature or habitat water level changes on generative shoot growth were not observed. However, two-season measurements of maximum quantum yield of photosystem II photochemistry showed that C. mariscus is welladapted to high habitat water level and might be sensitive to habitat water level fluctuations, when the water level falls below 5 cm. On the north-eastern limit of the distribution range the number of generative shoots of C. mariscus in the next growing season is affected by previous autumn drought and temperature below 0 °C as well. [ABSTRACT FROM AUTHOR]

In the initial phase of growth in an oligo-humotrophic lake, Cladium mariscus forms a dense and tall sawgrass bed invading the open water in the form of a floating mat. High densities of submerged evergreen perennial stems of C. mariscus, over two metres high and abundantly fruiting, ensure its persistence, and form a natural barrier to the invasion of other species. Dense mats of sawgrass are formed as a result of clonal and rhizome growth. Although diaspore production is abundant under natural conditions, only vegetative propagation of stems was observed. In different variants of the experiment only seeds wintering on stems of mother plants were capable of germinating. Hard seed coats had an important effect on the germination capacity of seeds.

We present the paleoecological development of a rich fen located in the dune area on the SE Baltic coast, during the last 7500 years. The Apšuciems Mire hosts rare and endangered plant communities in Europe, such as Schoenus ferrugineus and Cladium mariscus. Analysis at high-resolution of plant macroremains in two peat cores was carried out to reconstruct local vegetation succession and fluctuations in moisture availability on the peatland, while a pollen record was developed to reconstruct plant succession, moisture variability and human activity at the regional scale. Based on the presence or the absence of macroremains of plants that occur in wet habitat e.g. Cladium mariscus, Schoenoplectus tabernaemontani, Alisma plantago-aquatica and Botrycoccocus we distinguished four wet periods ca. 6000, 2000, 1750-1550, 1200-150 cal yr. BP and four dry periods (ca. 7000, 4600-4200, 1800-1750, 1550-1200 cal yr. BP) in the peatland's development. A water level increase at 1200 cal yr. BP triggered the development of plant communities containing Chara sp., Schoenoplectus tabernaemontani, then Cladium mariscus. Our study shows a link between climate change at the regional scale and vegetation development in Apšuciems Mire. We showed that changes in vegetation structure during last 150 years was caused by drainage and human activity. [ABSTRACT FROM AUTHOR]

For the first time in the published literature, a study is described concerning the use of the saw-sedge Cladium mariscus ( C. mariscus) for adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous systems. Among the experiments carried out, the elemental composition of C. mariscus was determined (C = 48.0 %, H = 7.1 %, N = 0.95 %, S = 0.4 %), FTIR spectroscopic analysis was performed to confirm the chemical structure of the adsorbent, and porous structure parameters were measured: BET surface area ( A = 0.6 m/g), total pore volume ( V = 0.001 cm/g) and average pore size ( S = 6.6 nm). It was shown that the effectiveness of removal of 2,4-D from aqueous systems using C. mariscus depends on parameters of the process: contact time, system pH, mass of sorbent, and temperature. Maximum adsorption was attained for a solution at pH = 3. Further increase in the alkalinity of the tested systems led to a reduction in the effectiveness of the process. The kinetic of adsorption of 2,4-D by C. mariscus was also determined, and thermodynamic aspects were investigated. The experimental data obtained correspond to a pseudo-second-order kinetic model of type 1. Additionally the negative values obtained for Δ Hº indicate that the process is exothermic, and the negative values of Δ Gº show it to be spontaneous. As the temperature of the system increases the spontaneity of adsorption is reduced, in accordance with the exothermic nature of the process. [ABSTRACT FROM AUTHOR]

Globally important U.K. fens are in poor condition, principally due to abandonment, following cessation of traditional mowing and grazing in recent decades. In the absence of management, rich fen flora are displaced as a result of succession. This leads to an increase in competitive species and subsequent biomass accumulation. In order to reverse this trajectory and increase species richness, management consisting of a single mowing event was employed. Mowing was conducted in two degraded fen communities in north-west Wales (U.K.) across three sites: (i) a species rich, tussock alkaline mire, dominated by Schoenus nigricans and Juncus subnodulosus (SN community) and (ii) a species poor basin mire Cladio-Molinietum dominated by Cladium mariscus (CM community). The early vegetation responses were monitored over two years. Results show a large treatment effect on species richness in the CM community, where mean species richness increased by 51% in the second year following mowing. Consequently, total species number across all sites increased to 74 in the treatment compared to 44 in the control. Mowing reduced vegetation height and litter cover and increased bare ground. These treatment effects combined with a reduction in graminoid and shrub cover collectively contributed to the initial stages of rehabilitation. Conversely, the SN community showed no increase in species richness, in spite of a reduction in litter cover and increased bare ground. Strong site heterogeneity and a sustained canopy height caused by rapid re-growth of the dominant graminoid S. nigricans may have impeded treatment effects. Therefore, increased mowing frequency in alternate years, switching between autumn and summer would be necessary to develop species richness in the SN community. Ongoing intervention in each fen community is needed to achieve an optimal trajectory of increased rich fen and reduction of secondary succession species. [ABSTRACT FROM AUTHOR]

Copyright of Ardeola is the property of Sociedad Espanola de Ornitologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Contributii Botanice is the property of Contributii Botanice and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The sedge,Cladium mariscus, has been identified in Middle Stone Age deposits at the shelter Sibudu, South Africa, where the leaves were used as “bedding” – an informal floor covering for various activities.Cladium mariscusnutlets were recovered from layers 73 000–39 000 years old and are likely to have entered the shelter on the plants harvested for bedding. This paper explores the possibility that, in addition to the use ofCladium mariscusleaves for bedding, the nutlets were collected for food. The underground storage organs and nutlets of many sedge species are eaten by contemporary people and they are known to have been eaten in the past at other sites. Nutritional analysis of the nutlets and rhizomes ofCladium mariscusindicates their potential as a food source, notwithstanding the small size of the nutlets. Although there is no evidence for the preparation ofCladium mariscusfor consumption at Sibudu, the abundant nutlets produced by the plants, their nutritional value and the ease of harvesting the nutlets indicate that they could have been a useful dietary item. At Sibudu, as early as 70 000 years ago, the complicated mastic recipes for hafting stone tools indicate that the shelter inhabitants possessed advanced pyrotechnological skills and sophisticated knowledge of the chemical properties of materials. It is possible that these abilities were applied to the processing ofCladium mariscusnutlets. Such activities could imply an early example of intensive collection and possible processing of a particular plant food. [ABSTRACT FROM PUBLISHER]

This study represents the first attempt to outline the dynamics of litter decomposition of Cladium mariscus (cut-sedge) and Phragmites australis (common-reed) in Las Tablas de Daimiel National Park (Central Spain). From April 1998 to September 1999, two experiments were conducted to measure the overall decomposition in large-pore bags (7 months) and the chemical-microbiological decomposition in entire bags (14 months). Despite the hypertrophic condition of the wetland, that might have enhanced plant litter decaying rates, decomposition was a slow process in Las Tablas de Daimiel for both species, resulting in more than 50% of initial biomass a year and a half later. There were no significant correlations between environmental variables and decomposition rates. An initial phase of leaching with the highest rates (P < 0.05) of mass loss and nutrients occurred for both plant species. Throughout the incubation period, no significant differences were observed between both species and experiments, and the average daily rates of mass loss were low: 0.0022 ± 0.001 day–1 for C. mariscus and 0.0029 ± 0.002 day–1 for P. australis in the overall decomposition experiment, and respectively 0.0019 ± 0.001 day–1 and 0.0016 ± 0.001 day–1 due to chemical-microbiological decomposition, suggesting the negligible significance of invertebrates in the plant decomposition process. Furthermore, no significant difference was observed for nutrient release, except that Phragmites lost more phosphorus (P < 0.1) than Cladium. Plant litter decaying rates were roughly an order of magnitude lower than nutrient release rates in both species. Our results suggest that slow decomposition rates of helophitic plant biomass increases organic matter sedimentation and reduces water quality of Las Tablas de Daimiel National Park.

Pivovaroff, A.L.; Swift, C.; Battaglia, L.L.; Kunz, B.; Platt, W.J., and Yoder, C.L., 2015. Physiological profiles as indicators of response to hurricane disturbance for three coastal wetland species. Hurricanes alter light and water availability via canopy damage and storm surge delivery and are expected to intensify with climate change. Plant species respond to environmental changes by making physiological adjustments in situ or through distribution changes. Three years after Hurricane Katrina, we compared functional traits and water relations among three species along the coenocline at Weeks Bay National Estuarine Research Reserve, Fairhope, Alabama, U.S.A. Based on posthurricane distribution changes for these species, we hypothesized that (1) Cladium mariscus, whose distribution expanded slightly, is responsive to increased light availability in the disturbed forest at the landward end but is strongly limited by water stress at its seaward edge; (2) Baccharis halimifolia, whose distribution shifted and abundance increased posthurricane, is responsive to increased light availability, cannot tolerate very low light levels or water logged soils, but can tolerate moderate salinity; and (3) Morella cerifera, whose distribution remained unchanged, would show little or no difference in measured functional traits and water relations at its landward vs. seaward edges. Cladium mariscus showed decreased water potential ( Ψ) at its seaward edge, but leaf mass per area (LMA) did not vary as forest cover increased landward. Baccharis halimifolia exhibited lowest LMA and highest Ψ in the middle of its distribution, but was least vulnerable to cavitation ( Ψ50) with increased forest cover. Morella cerifera exhibited no difference in water stress, wood density, or Ψ50 across its distribution. Our results suggest differences in physiological response to light availability and water stress may affect the postdisturbance distribution of plant species and influence changes in distribution of species exposed to chronic sea level rise. [ABSTRACT FROM AUTHOR]

The history of the occurrence of Cladium mariscus (Cyperaceae) in NE Poland at the north-eastern limit of its distribution in Europe is discussed. The decline of the species may be related to gradual oligotrophication of its habitats, caused by the isolation of calcareous deposits and the decline of calcium carbonate in the substratum. The presence of C. mariscus in Kojle and Perty, lakes in NE Poland, is related to the occurrence of calcareous sediments, which may compensate for the lack of sufficient warmth. The occurrence of calcium carbonate in the substratum allows for the growth of C. mariscus in areas that are influenced significantly by a continental climate. The abundance of Ca2+ cations in the substratum compensates for that climatic factor. [ABSTRACT FROM AUTHOR]

The Middle Stone Age deposits at Sibudu contain sedge (Cyperaceae) nutlets, which previously have been interpreted as indirect evidence of bedding. Scanning electron microscopy was used to identify the sedge nutlets through comparison of archaeological specimens with modern analogues. The presence of nutlets of Cladium mariscus (L.) Pohl subsp. jamaicense (Crantz) Kük, a 1-3 m tall sedge with long scabrid leaves, was unexpected and challenges the bedding hypothesis because of the minute sharp hairs along the midrib and margins of the leaf blades. Nevertheless, we argue for the use of Cladium as bedding material, possibly as the foundation on which softer matter was laid. It is possible that the Cladium nutlets and rhizomes may have been eaten and that the plant was also used as kindling or fuel. [ABSTRACT FROM AUTHOR]

Synthetic wastewaters simulating physically pre-treated low-loaded winery effluents were treated for four months with five pilot-scale horizontal subsurface flow constructed wetlands (HSSF-CWs) using different plants. Species under study were Phragmites australis (HSSF-CW2), Lythrum salicaria (HSSF-CW3), Cladium mariscus (HSSF-CW4), and Iris pseudacorus (HSSF-CW5). The designation HSSF-CW1 was not planted, and was used as a control. The mean dissolved oxygen and oxidation-reduction potential values in all HSSF-CWs indicated anaerobic conditions in the bulk liquid. High pollutant-removal efficiencies were obtained. Apparently, the species with higher growth (Phragmites, Lythrum, and particularly Iris) improved total nitrogen (TN) and nitrogen as ammonium (N-NH4+) removals, but adversely affected sulphate (SO42-) anaerobic reduction. Chemical oxygen demand (COD) removal efficiencies were high, although there were no clear indications how the kinds of plants might have influenced this parameter. A statistical analysis of variance indicated that only N-NH4+ removal efficiencies were statistically different owing to the influence of the different plants. In a second 6 month experimental period, polyphenols (13 mg L-1) were added to the synthetic wastewater to study possible inhibition effects. The addition of polyphenols did not seem to cause inhibition effects on COD, TN, and N-NH4+ removals, but clearly negatively affected SO42- removal. A new two-way analysis of variance confirmed that only SO42- removal was negatively affected by polyphenols, while the effects of the different plants were only significant for N-NH4+ removal. Polyphenols were nearly completely removed. First order rate constants obtained for COD, TN, SO42-, and polyphenol removals were similar to those reported by other authors. [ABSTRACT FROM AUTHOR]

This study describes the long-term changes of spatial patterns of cut-sedge ( Cladium mariscus) and common reed ( Phragmites australis) in the Spanish floodplain wetland Las Tablas de Daimiel. Using seven sets of aerial photographs, we determined changes in their spatial patterns (size of patches) between 1945 and 2001 that resulted from combinations of natural change and anthropogenic stress (irrigated agriculture, waste water discharge, fire, ploughing). Our approach consisted in using 1 ha cells as units of spatial resolution in principal coordinates of neighbour matrices and spatial correlograms to assess the spatial scale of interest and spatial patterns at (1) the whole wetland and (2) two areas of the wetland with locally contrasting biophysical settings and anthropogenic stress history. Results showed that vegetation spatial patterns were influenced by natural variability until the 1970s. Thereafter, anthropogenic perturbation became the main driver of vegetation change, especially in the lower part of the wetland where local impacts were stronger. Natural variability did not fragment cut-sedge patches, and the effects of biological traits were less important for its spatial pattern. By contrast, man-made change resulted in a marked cut-sedge cover decrease and patch fragmentation, and the importance of its biological traits on spatial patterns increased. The trends of reed spatial patterns were generally opposite to, but not as clear as those for, cut-sedge. The trends of spatial patterns were especially evident at very broad (3,500–10,000 m) and broad (1,000–3,400 m) spatial scales. Competition for space and abiotic factors (water quality and water depth) were not strong predictors of cover variability at the 1-ha scale, particularly in the lower area of the wetland. This suggests that other environmental variables need to be considered in spatially explicit modelling of vegetation spatial patterns in wetlands. Consideration of spatial hierarchies and species-specific ecological traits is paramount to the conservation of degraded wetlands. [ABSTRACT FROM AUTHOR]

This project studied domestic wastewater treatment by horizontal subsurface flow (HSSF) constructed wetlands (CW) and compared the effect of four different plant species on the operating conditions, dissolved oxygen (DO), and redox potential (ORP), and their efficiency on pollutants removal. Five HSSF CWs were fed for 10 months with low loaded synthetic domestic wastewater, using theoretical hydraulic residence time of 7.6 days. The plant species under study were the following: Phragmites australis (CW1), Lythrum salicaria (CW3), Cladium mariscus (CW4) and Iris pseudacorus (CW5). CW2 was not planted and this was used as control. Qualitative measurements determined a greater growth of Lythrum salicaria and Iris pseudacorus than the others. Dissolved oxygen concentrations were very low in the entire bulk liquid of all the CWs. Also ORP values were very similar in all wetlands, dealing with facultative anaerobic environments. All planted wetlands improved pollutants removal compared with the unplanted control wetland. The performances in terms of COD, TN, TP and SO42- removal obtained by the different CWs were in the ranges 80-90%, 35-55%, 15-40% and 45-60% respectively. Lythrum salicaria and Iris pseudacorus, which exhibited greater growth, were always the most efficient species that improved not only nutrients plant uptake but also other microbial removal processes probably due to a higher aeration potential, such as nitrification or aerobic respiration. Sulphate reduction was the most important mechanism for COD removal. Cladium mariscus, an autochthonous plant that grows in the south-central Iberian Peninsula, was less efficient than Lythrum salicaria and Iris pseudacorus, but improved the unplanted wetland wastewater efficiency. [ABSTRACT FROM AUTHOR]

The effects of aquatic macrophyte (willows and sawgrass) removal on flow velocity, tufa deposition, POM dynamics, and macroinvertebrate community structure were studied in the tufa barrier habitats of the barrage system of Plitvice Lakes, Croatia. Samples were collected from two hydraulic habitats (fast > 100 cm s−1 and slow < 100 cm s−1) at both a control (no macrophytes removed) and impact (macrophytes removed) site. Samples were collected with a core sampler (four layers in vertical profile of barrier bed) monthly on 6 dates before and 7 dates after the removal of macrophytes. Macrophytes were removed in May 2002 at the impact site. After the macrophyte removal flow velocity decreased significantly at both hydraulic habitats. Retarded flow resulted in: (a) a decrease in macroinvertebrate density and diversity since most of the taxa were rheophilic (preferring habitats with higher flow velocity) and (b) an increase in POM concentrations (FPOM and UPOM) since decreases in flow velocity facilitate particle deposition in lotic habitats. The effects of macrophyte removal were present, and diminish along the vertical sediment profile of the barrier bed. Tufa deposition was not influenced by the macrophyte removal. [ABSTRACT FROM AUTHOR]

The level of artificial and natural radionuclide concentration as well as heavy metal content were determined in samples of saw sedge and peat collected in the Special Protection Area of peat bogs near Chelm (Poland). Gamma- and alpha-spectrometry with proper sample preparation were used to determine natural gamma-emitters, artificial 137Cs and alpha-radiating plutonium (238Pu and 239,240Pu). Non radioactive elements were determined by AAS. Rather low level of heavy metal concentration in all samples was found, however, the transfer factors were significant. Peat contamination with artificial radionuclides (137Cs and plutonium) was low. Contrary, the concentration of these isotopes in saw sedge was higher than normally observed in non contaminated areas, what is a result of a significant transfer factor. [ABSTRACT FROM AUTHOR]

Abstract: Phragmites australis tolerates a wider range of ecological conditions than Cladium mariscus and thus may be better adapted to disturbance resulting from human manipulations. We hypothesised that the difference in ecological conditions was related to differences in photosynthetic ability under water stress. We compared the reactions of the two species to water deficit related to the summer drawdown in the Mediterranean regions that may be enhanced by drainage for human activities. Stress tolerance was evaluated in a pot experiment measuring pigment contents, chlorophyll fluorescence and gas exchanges, growth rates, living and dead biomass, for plants grown in waterlogged conditions or submitted to permanent or temporary drainage. Reed was favoured by the first days of drainage with an increase in CO2 assimilation by approximately 5μmolm−2 s−1 and an increase of the elongation rates from 1 to 1.5cmd−1, indicating waterlogged conditions were not optimal for this species. While pigment content showed no significant effects, growth rate, percentage live above-ground biomass, chlorophyll fluorescence and net rate of CO2 assimilation declined significantly for both species from days 5 to 7 after drying started. Assimilation rates reached 2.3 and 0.3μmolm−2 s−1 on day 9 for sawsedge and reed, respectively. Sawsedge had a 50% greater assimilation rate in the waterlogged conditions, but its responses to water loss in terms of declining growth rate and CO2 assimilation started on day 5 versus 7 for reed. By contrast, the condition of PSII as indicated by chlorophyll fluorescence was affected more in reed. Both growth rates and rates of CO2 assimilation had completely recovered for both species within 3 days of re-wetting. Our results reflect the evergreen character of sawsedge leaves that are hardly damaged by stress but decrease their activity. Reed leaves die upon excessive stress and plants may shed leaf as an adjustment to stress. Sawsedge photosynthesis will be optimal in waterlogged conditions whereas that of reed will be constant within a broad range from slightly drained to mild stress. Those responses to drainage at the leaf scale may partly explain the difference in habitat where both species are usually found. [Copyright &y& Elsevier]

To assess whether winter mowing in wetlands fulfils the aim of preventing succession towards drier communities, 34 permanent quadrats (15 m 2) were surveyed annually from 1984-1985 to 2000 within large mown and unmown (control) areas (several ha) in a calcareous lake shore fen (W Switzerland). Three trends were noticed: decrease of aquatic species, spread of Cladium mariscus and establishment of woody species (especially Alnus glutinosa and Frangula alnus). None of these trends was prevented by mowing, but mowing did prevent the accumulation of C. mariscus litter and kept woody saplings small. Succession was generally slow and often occurred in the form of sudden, discrete changes. Plant species richness increased with mowing and remained constant without mowing. Soil disturbance by the mowing machine contributed more to the effects of management on species composition than the periodic removal of biomass. It is concluded that mowing every three years in winter is insufficient to preserve semi-aquatic communities against succession but sufficient to maintain the plant species richness of a low productive, regularly flooded fen. [ABSTRACT FROM AUTHOR]

Meadows are often managed by mowing to prevent succession and brushwood encroachment. This management practice is efficient to maintain plant diversity, but the effect on arthropod groups is less well known. We sampled spiders in the Grande Caric¸aie (Switzerland), a site of nature conservation importance, in two types of wet meadows, an unmanaged site and one 2-years-old mown conditions. Numbers of individuals for the most abundant families, diversity measures, and indicator taxa were compared among vegetation and treatment types. The results indicate that the less mobile spiders and species linked to litter or dead reeds, including rare species, are reduced by mowing. Present management consists in triennial mowing of 2–4 ha non-contiguous sectors. We investigate the conflict between the need to mow the meadows to maintain them, and the negative effect of mowing on spider communities. We therefore propose a new management scheme aimed at maintain the vegetation while lessening its negative effects on spider communities by providing refuges. [Copyright &y& Elsevier]

A three-year study was carried out in Las Tablas de Daimiel National Park, a Spanish semi-arid wetland, to describe eutrophication patterns and the responses of the main primary producers in contrasting inundation years. Total and dissolved nitrogen and phosphorus, phytoplankton chlorophyll-a (monthly) and emergent macrophyte cover (yearly) were measured together with water levels. Water balances were taken to assess phosphorus and nitrogen annual nutrient budgets. The wetland could be termed hypertrophic. Nutrients displayed distinct seasonality because nitrogen peaked both in winter and summer, whereas phosphorus did so in late spring and early summer. A reduction in both total nitrogen and phosphorus in humid years due to higher water levels was also observed. An important spatial heterogeneity in nutrient content occurred throughout the study, part of which could be ascribed to hydrological fluctuations since the input site showed higher mean values in rainy years. Mass balances suggested that sedimentation played a key role in nutrient dynamics, with macrophyte leaching and waterfowl additions being minor sources. Internal loading was much higher than external loading in this wetland, thereby being responsible for higher sedimentation rates. Phytoplankton chlorophyll-a displayed seasonality, with peaks in late summer, when macrophyte activity was decreasing. No relationship between either chlorophyll-a and nutrients or hydrological conditions could be ascertained for most sampling stations and years of study. However, the water level-dependent, emergent macrophyte sawgrass (Cladium mariscus) presented a statistically significant relationship with both nitrogen and phosphorus. Our results demonstrate that macrophytes must be taken into account in wetland eutrophication models. A conceptual model comparing the responses of primary producers to eutrophication in lakes and wetlands is outlined. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-proxy long-term ecological studies are important tool to indicate peatland state. • Climate change and land cover in the catchment impact development of spring-fed fen. • Mollusc populations are sensitive to hydrological disturbances. • Restoring spring-fed ecosystems may also require catchment restoration. 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 the Baltic Sea coast (Latvia) in relation to environmental changes, substrate and human activity, we have undertaken high-resolution analyses of plant macrofossils, pollen, mollusc, stable carbon (δ13C) and oxygen (δ18O) isotopes combined with radiocarbon dating (AMS) in three coring locations. Our study revealed that peat deposits began accumulating ca. 7000 cal. yr BP and calcareous deposits (tufa) from 1450 cal. yr BP, coinciding with regional hydrological changes. Several fire events occurred between 4000 and 1600 cal. yr BP, which appeared to have had a limited effect on local vegetation. The most significant changes in the forest and peatland ecosystems were at 3200 cal. yr BP associated with a dry climate stage and high fire activity, and then between 1400 and 500 cal. yr BP potentially associated with temperature changes during the Medieval Climate Anomaly (MCA) and Little Ice Age. Hydrological disturbances in the peatland catchment from 1400 cal. yr BP were most likely strengthened by human activity (deforestation) in this region. The relationship between the development of this peatland and changes in its catchment area, such as land cover changes or fluctuations in groundwater levels, suggest that protection and restoration of spring-fed fen ecosystems should also include the surrounding catchment. The presence of calcareous sediments, as well as appropriate temperature and local hydrological conditions appear to be the most crucial factors controlling Cladium marisus populations in our site - currently at the eastern limit of its distribution in Europe. [ABSTRACT FROM AUTHOR]