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EN
Fine particulate organic matter (FPOM), originated by aggregation of smaller particles and by decomposition of bigger particles, usually presents the dominant energy and nutrient source in the primary river net. Relationships between detrital components, environmental factors and macroinvertebrate composition were investigated in 52 submontane organogenic spring areas in small catchment in the Sumava foothills, Czech Republic. All three types of springs (helocrenes, rheocrenes and limnocrenes) were represented, as well as springs with the transitional character. The selected springs were permanent, with water discharge higher than 0.1 L s[^-1], they all were coldwater and stenothermic, with the winter water temperature at the point of the source ranging from 2.0 to 9.9[degrees]C. At each spring area, the main morphological and physical characteristics of the spring and surrounding area were recorded. Samples of detritus were collected (using the 2 mL sampling tube) from up to 5 microhabitats at each spring, usually macrophyte vegetation, point of the source, detrital deposition, sand, algal mat, leaf litter or moss, accordingly to the microhabitats, which were present. Macroinvertebrates were semiquantitatively sampled using a 15-cm circular sampler with 0.8 mm mesh, to the orders or lower taxa were determined. Water samples were taken, and analyses of the main physico-chemical factors were carried out. In our set of springs, organic substrate prevailed. Only small differences in the physico-chemical parameters (e.g. pH = 5.96 [plus or minus] 0.39; mean [plus or minus] SD) and low concentrations of nutrients (e.g. N-NO3[^-] = 0.79 [plus or minus] 0.86 mg L[^-1], ortho-PPO4[^-] = 0.0336 [plus or minus] 0.0275 mg L[^-1]) were noted, whereas studied geomorphological parameters and microhabitat types were more diverse. The proportion of basic microscopically differentiable components of the detritus was similar in all spring types and microhabitats. In all study sites, faecal pellet content was dominant in the detritus (49%) followed by plant residuals (26%) and amorphous matter (21%). High faecal pellet content is considered to be a consequence of a steadily low temperature in the springs. The correlation among the presence of macroinvertebrate groups and particular detrital components content was not significant, except for Trichoptera; the abundance of this group was positively correlated with the proportion of plant residuals in detritus in vegetation microhabitats. Faecal pellet content showed a weak negative correlation with N-NH4 concentration, which is probably the result of faster faecal pellet decomposition in springs with higher N-NH4 contents.
EN
This paper discusses predictions of particulate organic carbon (POC) concentrations in the southern Baltic Sea. The study is based on the one-dimensional Particulate Organic Carbon Model (1D POC), described in detail by Dzierzbicka-Głowacka et al. (2010a). The POC concentration is determined as the sum of phytoplankton, zooplankton and dead organic matter (detritus) concentrations. Temporal changes in the phytoplankton biomass are caused by primary production, mortality, grazing by zooplankton and sinking. The zooplankton biomass is affected by ingestion, excretion, faecal production, mortality and carnivorous grazing. The changes in the pelagic detritus concentration are determined by the input of dead phytoplankton and zooplankton, the natural mortality of predators, faecal pellets, and sinks - sedimentation, zooplankton grazing and biochemical decomposition. The model simulations were done for selected locations in the southern Baltic Sea (Gdańsk Deep, Bornholm Deep and Gotland Deep) under predicted conditions characterized by changes of temperature, nutrient concentrations and light availability. The results cover the daily, monthly, seasonal and annual POC concentration patterns in the upper water layer. If the assumed trends in light, nutrients and temperature in the southern Baltic correctly predict the conditions in 2050, our calculations indicate that we can expect a two- to three-fold increase in POC concentration in late spring and a shift towards postponed maximum POC concentration. It can also be anticipated that, as a result of the increase in POC, oxygenation of the water layer beneath the halocline will decrease, while the supply of food to organisms at higher trophic levels will increase.
EN
Particulate Organic Carbon (POC) is an important component in the carbon cycle of land-locked seas. In this paper, we assess the POC concentration in the Gdańsk Deep, southern Baltic Sea. Our study is based on both a 1D POC Model and current POC concentration measurements. The aim is twofold: (i) validation of simulated concentrations with actual measurements, and (ii) a qualitative assessment of the sources contributing to the POC pool. The POC model consists of six coupled equations: five diffusion-type equations for phytoplankton, zooplankton, pelagic detritus and nutrients (phosphate and total inorganic nitrogen) and one ordinary differential equation for detritus at the bottom. The POC concentration is determined as the sum of phytoplankton, zooplankton and pelagic detritus concentrations, all expressed in carbon equivalents. Bacteria are not simulated in this paper. The observed large fluctuations of POC concentrations are attributed to its appreciable seasonal variability. The maximum concentration of POC varied between 870 mgC m-3 in May and 580 mgC m-3 in September, coinciding with the period of maximum dead organic matter and phytoplankton biomass concentrations. The results of the numerical simulations are in good agreement with observed values. The difference between the modelled and observed POC concentrations is equal to 3-28% and depends on the month for which the calculations were made, although no time trend of the difference is observed. The conclusion is that the numerical simulations are a sufficiently good reflection of POC dynamics in the Baltic.
EN
Organisms showing the properties of bioindicators respond to changes in the biotope in a specific way. Those organisms are susceptible to toxic substances or on the contrary they are tolerant to toxins brought into the biotope. Such tolerance means that bioindicators are able to accumulate the pollutants to such extent that is lethal to other living organisms. Using molluscs and their abilities to accumulate heavy metals in amounts higher than those in the environment makes it possible to use this group of organisms as bioindicators of water biotopes. The diversity of types of nutrition and variety of nourishment (deposit-feeding, filtration of suspension and phytophagous properties) allow to indicate differences in concentration of heavy metals despite the origin of species in the same water area. In case of malacofauna preying on bottom deposits it is possible to detect the relation of migration of elements in a water - plant - bottom deposit - malacofauna system. The research was carried out in the Kielce Lagoon - a reservoir formed within the borders of the city of Kielce by closing the Silnica River valley with a weir at 8 km. There are recreational, residential and industrial areas surrounding the reservoir. The trunk road in direction to Lodz being the source of transportation-related pollution is located in the close neighbourhood. The municipal swimming pool from which chlorinated water is discharged to the reservoir is also located nearby. The lagoon is fed by a watercourse collecting the municipal pollutants from the Masłow Village located near the city of Kielce. The water of the Kielce Lagoon is highly polluted because of wide range of organic and inorganic compounds brought into the reservoir. The obtained results of chemical analyses allow to evaluate the cleanliness of the reservoir, form a warning system against danger and show malacofauna response to changes in the biotope.
PL
Organizmy wykazujące cechy bioindykatorów w charakterystyczny dla siebie sposób reagują na zmiany w biotopie. Są to najczęściej organizmy o dużej wrażliwości na substancje toksyczne lub odwrotnie, tzn. wykazujące wysoki stopień tolerancji względem wprowadzanych do biotopu toksyn. Tolerancja ta polega na zdolności bioindykatorów do kumulowania zanieczyszczeń w ilościach, które dla innych form życia stanowią wartości letalne. Wykorzystanie mięczaków i ich zdolności do koncentracji metali ciężkich w ilościach wyższych niż w środowisku stwarza możliwość użycia tej grupy organizmów jako bioindykatorów biotopów wodnych. Różnorodność sposobów odżywiania i rodzaj pobieranego pokarmu (żerowanie na osadach, filtracja zawiesiny, roślinożerność) pozwalają na wskazanie różnic w koncentracji metali ciężkich mimo pochodzenia gatunków z tego samego akwenu. W przypadku malakofauny żerującej na osadach dennych możliwe jest uchwycenie zależności migracji pierwiastków w układzie: woda - roślina - osad denny - malakofauna. Badaniami objęto Zalew Kielecki, zbiornik utworzony w granicach miasta Kielce poprzez zamknięcie doliny rzeki Silnicy jazem, na jej 8 km. Tereny wokół zbiornika zagospodarowane są zarówno na cele rekreacyjne, mieszkaniowe, jak i gospodarcze. Dodatkowo w bezpośrednim sąsiedztwie przebiega droga krajowa w kierunku Łodzi, będąca źródłem zanieczyszczeń komunikacyjnych, oraz zlokalizowany jest basen miejski, z którego wprowadzana jest do zbiornika woda chlorowana. Zalew zasilany jest ciekiem wodnym stanowiącym odbiornik zanieczyszczeń komunalnych z miejscowości Masłów, położonej w pobliżu Kielc. Ilość oraz różnorodność związków zarówno organicznych, jak i nieorganicznych, dostających się do zbiornika, powoduje, że wody zalewu są bardzo zanieczyszczone. Uzyskane wyniki analiz chemicznych oraz biologicznych pozwalają na ocenę stanu czystości zbiornika, stwarzają system ostrzegania przed zagrożeniem oraz pokazują reakcje malakofauny na zmiany zachodzące w biotopie.
EN
Studies on feeding of V. viviparus were carried out in the years 1995-2005 in dam reservoir (Zegrzyński Reservoir, Central Poland, 60 km long, mean depth ca 3.5 m, maximum depth at the dam up to 9 m, mean retention time from 1 to 15 days) and in the outlets of its tributaries (the Bug, Narew and Rządza rivers), in the Narew River and - in the years 2003-2006 - also in oxbow lakes of the Bug River. Sex ratio and size structure of snails were estimated. Both the content of intestines (detritus, algae, inorganic matter) and the gut fulfilment were analysed. Performed multi-factor analysis showed the effect of habitat, season and snail size (estimated from shell height) on food mass in the gut. Snails from dam reservoir and outlet stretches of three rivers showed the largest food mass in the gut. Intestines of snails from rivers and oxbow lakes were less filled. The largest food volumes were found in spring and summer. Only in viviparids from oxbow lakes the largest food mass in the gut was noted in the autumn. Food mass in the gut was largest in snails of the I (<8 mm) and IV (20-35 mm) size class. Food mass was similar in females and males. Differences were, however, noted in the ingested food mass between fertile and infertile females which was smaller in the former. In all studied sites the snails fed mainly on detritus which constituted from 70 to 90% of food mass ingested of all individuals. Detritus abundance in studied habitats might result in using it by snails as obligatory though low-energetic food source. Detritus contributed more to the food of viviparids from Zegrzyński Reservoir and from oxbow lakes, slightly less - to the food of those from outlet stretches of rivers and from the Narew River. Algae contributed from 5% (Zegrzyński Reservoir) to 15% (the Narew River) to the food mass in snail guts. Apart from diatoms, green algae, dinoflagellates and chrysophytes, also cyanobacteria were found in snail food mass. Green algae (46% of all algae) and diatoms (37% of all algae) constituted the largest part of viviparids algal diet in the reservoir. The share of chrysophytes and dinoflagellates made about 10%. More diatoms (up to 48%) and less green algae (up to 25%) were found in snails from outlet stretches of rivers. Guts of snails from the Narew River contained mainly diatoms (over 50%) and green algae (30%). Gut content of snails from oxbow lakes was dominated by green algae (50% of all algae) and diatoms (35% of all algae). Inorganic matter in a form of mineral particles contributed least to the food of snails in the reservoir and in oxbow lakes (ca 5%) in comparison with snails from other sites. No food of animal origin was found. In general, it can be stated that the amount of food mass ingested and its composition differed rather slightly among studied habitats, seasons and individuals.
PL
Praca zawiera identyfikację form morfologicznych niespalonej materii organicznej pozostających w żużlach i popiołach lotnych, określenie ich zawartości oraz porównanie ich form z zawartością części palnych. Stwierdzono częste występowanie cenosfer i koronek w popiołach, a form masywnych w żużlach. Słaba korelacja pomiędzy zawartością części palnych, a zawartością form morfologicznych przypuszczalnie wynika z warunków spalania.
EN
The research presents the identification of char morphological forms in slags and fly ashes, determination of their quantity, comparison between their morphology and the unburned organic matter content. Cenospheres and laces are frequently present in ashes and massive forms are frequently present in slags. The weak correlation between the content of unburned organic matter and the content of char morphological forms probably can be related to combustion conditions.
EN
Resource heterogeneity in the lake littoral zones and streams often takes the form of leaf litter diversity. Since resource quality varies between leaf species, diversity of leaf litter inputs to these systems may alter detritivore dynamics. We challenged the assumption that stream detritivores view their leaf resources independently, and that shredder colonization dynamics were additive. We developed a null model that suggests the temporal coefficient of variation in abundance of detritivores declines as leaf diversity increases. We then conducted an experiment in which leaf composition was manipulated in a stream and shredder abundance was followed. Shredder stability was low on single leaf species, increased at intermediate levels, then declined at maximum levels. The null model did not predict the low stability observed, suggesting other ecological factors influenced shredder abundance. Non-additive patterns in colonization support the notion that leaf diversity leads to emergent properties, altering consumer dynamics in this ecosystem.
8
Content available remote Fine organic particles in a sandy beach system (Puck Bay, Baltic Sea)
EN
A total of over 550 samples of particulate organic matter (POM) were obtained from swash and groundwater samples taken on a monthly basis from seven localities on the sandy shores of Puck Bay in 2002 and 2003. Sandy sediment cores from the swash zone were collected to assess the amount of POM in the pore waters. The mean annual concentrations of POM varied between localities from 20 to 500 mg in groundwater and from 6 to 200 mg dm-3 in swash water. The carbon/nitrogen (C/N) ratio in suspended matter was always higher in groundwater (annual mean 12) than in swash water (annual mean 7). The C/N ratio indicates a local, algal origin of POM in the shallow coastal zone.
EN
This paper presents the numerical simulations of the influence of the zooplankton dynamics on the phytoplankton, zooplankton and nutrient biomasses in the sea. The numerical studies were carried out using a phytoplanktonzooplankton-nutrient-detrius PhyZooNuDe biological upper layer model with a full-developed regeneration mechanism and with regarding daily migration of zooplankton. In this model the zooplankton is treated not as "biomass" but as organisms having definite patterns of growth, reproduction, and mortalityassuming, also {Zoop} is composed of (i) cohorts of copepods with weights (W[i]) and numbers (Z[i]); then {Zoop} = SigmaW[i]Z[i]. The PhyZooNuDe model consists of three coupled, partial second-order differential equations of the diffusion type for phytoplankton, zooplankton, nutrients and one ordinary first-order differential equation for benthic detritus pool, together with initial and boundary conditions. The calculation were made for 35 days in an area 0 mniejsze lub równe z mniejsze lub rowne 20m with a vertical space step of 10 cm and a time step of 5 min. The experimental data, gathered during the PEX'86 international scientific experiment of the Baltic states, and subsequently by the International Council for the Exploration of the Sea, were used as the input data for the calculations. The simulation given here demonstrated as factors of grazing, growth, metabolism, reproduction, and mortality of copepods are important since can alter the nature of the interactions of plants and herbivores.
EN
Concentrations of copper, zinc, manganese, iron, cadmium and lead were investigated in chosen mollusc species from the Zegrzyński Reservoir (Central Poland) against the background of metal content in water, seston, bottom sediments, macrophytes, periphyton, and detritus. These concentrations were generally comparable to values reported from environments slightly contaminated with heavy metals. Relatively small interspecific variation in accumulation of non-essential metals (Pb, Cd) distinctly lower than in the case of essential metals resulted mainly from the lack of regulation of their level in an organism. It is conducive to molluscs application in bioindication of environmental contamination with Pb and Cd.
PL
Badano stężenie miedzi, cynku, manganu, żelaza, kadmu i olowiu w tkankach miękkich i muszlach wybranych gatunków mięczaków ze Zbiornika Zegrzyńskiego na tle ich poziomu w wodzie, sestonie, osadach dennych, makrofitach, peryfitonie i detrytusie. Stężenia te osiągały na ogół wartości porównywalne do podawanych ze środowisk w niewielkim stopniu zanieczyszczonych metalami ciężkimi. Stosunkowo małe zróżnicowanie gatunkowe kumulacji metali ksenobiotycznych (Pb i Cd) w badanych ślimakach i małżach (dużo mniejsze, niż w przypadku metali biofilnych) wynikające głównie z braku regulacji poziomu tych pierwiastków w organizmie sprzyja wykorzystaniu mięczaków w bioindykacji skażenia badanego ekosystemu ołowiem i kadmem.-
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