9 research outputs found

    Analiza kvaliteta vode reke Jablanice na osnovu zajednice vodenih makroinvertebrata

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    Cilj rada je da se prikažu rezultati ocene kvaliteta vode reke Jablanice (sliv Kolubare) zasnovane na prisutnoj zajednici vodenih makroinvertebrata. Jablanica je relativno kratka (25 km) desna sastavnica, koja u blizini Valjeva sa Obnicom (leva sastavnica) formira Kolubaru. Kolubara, kao poslednja veća pritoka Save, protiče kroz područje sa izraženim i različitim antropogenim uticajima. Sama Jablanica nastaje spajanjem većeg broja potoka sa obronaka planina Jablanik i Medvednik. U skladu sa zahtevima EU prilikom ocene stanja rečnih sistema neophodno je utvrđivanje referentnih uslova. Da bi se utvrdilo recentno stanje, i usaglašenost sa zahtevima za dostizanje referentnog statusa, izvršeno je ispitivanje ove reke u aprilu 2013. godine na tri lokaliteta gornjeg toka. Kao parametri za ocenu kvaliteta vode, korišćeni su sledeći pokazatelji: ukupan broj taksona, saprobni indeks (SI; Zelinka & Marvan), BMWP i ASPT skorovi, broj taksona grupa Ephemeroptera, Plecoptera and Trichoptera (EPT) i indeks diverziteta (SWI; Shannon-Wiener’s indeks). Zabeležena su ukupno 72 taksona makroinvertebrata. Kao najraznovrsnije grupe izdvajaju se Trichoptera (16 taksona) i Ephemeroptera (15 taksona). U odnosu na saprobnu vrednost, utvrđeno je da je većina prisutnih taksona osetljiva na organsko zagađenje (ksenosaprobni i oligosaprobni organizmi). Dobijene vrednosti praktično svih korišćenih pokazatelja kvaliteta vode, upućuju na veoma dobar status (klasa I), čime su ispunjeni uslovi da se ispitivani deo toka Jablanice može smatrati referentnim stanjem, za potrebe istraživanja sliva Kolubare. Puštanje u rad akumulacije u Rovnima (srednji tok Jablanice) može izmeniti zatečeno stanje, zbog čega je neophodan redovni monitoring

    Analiza kvaliteta vode reke Mlave na osnovu vodenih makroinvertebrata

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    Cilj rada je da se predstave rezultati ispitivanja kvaliteta vode reke Mlave, zasnovani na prisutnoj zajednici vodenih makroinvertebrata. Mlava, sa dužinom toka od 78 km i površinom sliva od 1885 km², jedna je od značajnijih pritoka Dunava u Srbiji. Kao najvažniji izvori komunalnog i industrijskog zagađenja mogu se izdvojiti gradovi Požarevac (70000 stanovnika; u donjem toku) i Petrovac na Mlavi (8000 stanovnika; srednji tok), kao i Žagubica (2600 stanovnika; gornji tok). Slivno područje, naročito u srednjem delu toka, je i pod uticajem spiranja sa poljoprivrednih površina, kao i komunalnih otpadnih voda iz brojnih manjih naselja. Negativni efekti, ovih antropogenih uticaja mogu biti još izraženiji, zbog specifične hidrologije, odnosno preovlađivanja stanja niskih voda u slivu ove reke. Uzorkovanje je izvršeno u julu 2013. godine. Kao parametri za ocenu kvaliteta vode, korišćeni su sledeći pokazatelji: Saprobni indeks (SI; Zelinka & Marvan), BMWP i ASPT skorovi, broj taksona grupa Ephemeroptera, Plecoptera and Trichoptera (EPT) i indeks diverziteta (SWI; Shannon-Wiener’s indeks). Ukupno 72 taksona makroinvertebrata su identifikovana. Insekti su bili najraznovrsnija komponenta, a u okviru njih najbrojnije su bile grupe Ephemeroptera (13 taksona) i Trichoptera (11 taksona). Najveća raznovrsnost zabeležena je na lokalitetu Leskovac (33 taksona). Većina taksona je tolerantna na određeni stepen organskog zagađenja (β –mezosaprobni i α–mezosaprobni organizmi), naročito u donjem delu toka (Rašanac i Požarevac). Vrednosti SI na svim lokalitetima upućuju na veoma dobar i dobar kvalitet vode (klase I i II). Vrednosti BMWP i ASPT ukazuju na veoma dobar kvalitet vode samo na lokalitetima u srednjem i donjem delu toka (Leskovac i Požarevac), dok je u gornjem delu toka, kvalitet vode, ili loš (BMWP), ili umeren do dobar (ASPT). I preostali pokazatelj (EPT), takođe, ukazuje na bolji kvalitet vode u donjem delu toka. Na osnovu svih korišćenih pokazatelja, kvalitet vode reke Mlave u julu 2013. godine se može oceniti kao dobar (klasa II)

    The relation between chironomid (Diptera: Chironomidae) assemblages and environmental variables: The Kolubara River case study

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    Chironomid larvae respond rapidly to environmental changes in aquatic ecosystems, with different species possessing different degrees of tolerance. Consequently, this group is considered an effective and reliable indicator of the ecological status. In this study, the relation between larval chironomid assemblages and environmental variables was examined at two sites on the Kolubara River. The nonparametric Mann-Whitney U test did not confirm significant seasonal differences between samples. Correspondence analysis indicated that the study sites are distinguished by their community composition. Based on forward selection analyses, 5 out of the 28 analyzed water parameters and 3 out of the 22 sediment parameters displayed the highest levels of correlation with chironomid assemblages. Forward selection analysis revealed that inorganic pollutants in the sediment (mercury, nickel and cadmium) exerted the greatest influence on the community. Results of canonical correspondence analysis indicated that the sediment characteristics have a more significant impact on chironomid communities than the analyzed water parameters. Our study confirmed that chironomids and sediment analyzes should be obligatorily included in the monitoring of ecological status, since chironomids are often a dominant component of benthic macroinvertebrate assemblages in freshwater ecosystems, with many species inhabiting the sediment with a proclivity for intake of toxic and persistent pollutants

    Unravelling the effects of multiple stressors on diatom and macroinvertebrate communities in European river basins using structural and functional approaches

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    International audienceRivers suffer from more severe decreases in species diversity compared to other aquatic and terrestrial ecosys- tems due to a variety of pressures related to human activities. Species provide different roles in the functioning of the ecosystem, and their loss may reduce the capacity of the ecosystems to respond to multiple stressors. The effects on diversity will differ based on the type, combination and severity of stressors, as well as on the char- acteristics of the community composition and tolerance. Multiple trait-based approaches (MTBAs) can help to unravel the effects of multiple stressors on communities, providing a mechanistic interpretation, and, thus, complementing traditional biodiversity assessments using community structure. We studied the relationships between diversity indexes and trait composition of macroinvertebrate and diatom communities, as well as envi- ronmental variables that described the hydrological and geomorphological alterations and toxic pollution (pes- ticides and pharmaceuticals) of three different European river basins: the Adige, the Sava, and the Evrotas. These river basins can be considered representative cases of different situations in European freshwater systems. Hy- drological variables were the main drivers determining the community structure and function in the rivers, for both diatoms and macroinvertebrates. For diatom communities, pharmaceutical active compound (PhAC) toxic units were also identified as a very important driver of diversity changes, explaining up to 57% of the variance in taxonomic richness. For macroinvertebrates, river geomorphology was an important driver of structural changes, particularly affecting Plecoptera richness. In addition, PhAC and pesticide toxic units were also identified as stressors for macroinvertebrate communities. MTBA provided a detailed picture of the effects of the stressors on the communities and confirmed the importance of hydrological variables in shaping the functional attributes of the communities

    Unravelling the effects of multiple stressors on diatom and macroinvertebrate communities in European river basins using structural and functional approaches

    No full text
    Rivers suffer from more severe decreases in species diversity compared to other aquatic and terrestrial ecosystems due to a variety of pressures related to human activities. Species provide different roles in the functioning of the ecosystem, and their loss may reduce the capacity of the ecosystems to respond to multiple stressors. The effects on diversity will differ based on the type, combination and severity of stressors, as well as on the characteristics of the community composition and tolerance. Multiple trait-based approaches (MTBAs) can help to unravel the effects of multiple stressors on communities, providing a mechanistic interpretation, and, thus, complementing traditional biodiversity assessments using community structure. We studied the relationships between diversity indexes and trait composition of macroinvertebrate and diatom communities, as well as environmental variables that described the hydrological and geomorphological alterations and toxic pollution (pesticides and pharmaceuticals) of three different European river basins: the Adige, the Sava, and the Evrotas. These river basins can be considered representative cases of different situations in European freshwater systems. Hydrological variables were the main drivers determining the community structure and function in the rivers, for both diatoms and macroinvertebrates. For diatom communities, pharmaceutical active compound (PhAC) toxic units were also identified as a very important driver of diversity changes, explaining up to 57% of the variance in taxonomic richness. For macroinvertebrates, river geomorphology was an important driver of structural changes, particularly affecting Plecoptera richness. In addition, PhAC and pesticide toxic units were also identified as stressors for macroinvertebrate communities. MTBA provided a detailed picture of the effects of the stressors on the communities and confirmed the importance of hydrological variables in shaping the functional attributes of the communities

    Large Graphene Quantum Dots Alleviate Immune-Mediated Liver Damage

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    We investigated the effect of large (40 nm) graphene quantum dots (GQDs) in concanavalin A (Con A; 12 mg/kg i.v.)-induced mouse hepatitis, a T cell-mediated liver injury resembling fulminant hepatitis in humans. Intravenously injected GQDs (50 mg/kg) accumulated in liver and reduced Con A-mediated liver damage, as demonstrated by histopathological analysis and a decrease in liver lipid peroxidation and serum levels of liver transaminases. The cleavage of apoptotic markers caspase-3/PARP and mRNA levels of proapoptotic mediators Puma, Noxa, Bax, Bak1, Bim, Apaf1, and p21, as well as LC3-I conversion to autophagosome-associated LC3-II and expression of autophagy-related (Atg) genes Atg4b, Atg7, Atg12, and beclin-1, were attenuated by GQDs, indicating a decrease in both apoptosis and autophagy in the liver tissue. This was associated with the reduced liver infiltration of immune cells, particularly the T cells producing proinflammatory cytokine IFN-γ, and a decrease in IFN-γ serum levels. In the spleen of GQD-exposed mice, mRNA expression of IFN-γ and its transcription factor T-bet was reduced, while that of the IL-33 ligand ST2 was increased. The hepatoprotective effect of GQDs was less pronounced in ST2-deficient mice, indicating that it might depend on ST2 upregulation. <i>In vitro</i>, GQDs inhibited splenocyte IFN-γ production, reduced the activation of extracellular signal-regulated kinase in macrophage and T cell lines, inhibited macrophage production of the free radical nitric oxide, and reduced its cytotoxicity toward hepatocyte cell line HepG2. Therefore, GQDs alleviate immune-mediated fulminant hepatitis by interfering with T cell and macrophage activation and possibly by exerting a direct hepatoprotective effect
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