Can Ephemeroptera, Plecoptera, Trichoptera (EPT) assemblage reflect nitrogen and phosphorus load in the riverine ecosystem?

The aim of this paper is to make a comparative analysis of benthic macroinvertebrate compositions in streams and rivers in Croatia with relation to different physical-chemical factors, especially nutrients. Samples were collected according to the AQEM method. At all the sites, 20 taxa were recorded of which Turbellaria, Gastropoda, Bivalvia, Oligochaeta, Hirudinea, Crustacea, Ephemeroptera, Odonata, Plecoptera, Heteroptera, Trichoptera, Coleoptera and Diptera were included in the present study. Water temperature mostly affected the composition of benthic macroinvertebrates to which it was inversely proportional. Nutrient enrichment, i.e., higher concentrations of ammonium, nitrates, nitrites, total nitrogen, orthophosphates and total phosphorus mostly affected Ephemeroptera, Plecoptera, Trichoptera and Diptera, by decreasing their diversity

Der Einfluss von physikalischen und chemischen Indikatoren und Metallen auf die Gemeinschaften von Eintagsfliegen, Steinfliegen und Köcherfliegen (EPT)

U ovom smo radu istraživali vezu između broja svojti unutar triju redova vodenih kukaca: vodencvjetova (Ephemeroptera), obalčara (Plecoptera) i tulara (Trichoptera), ukupnog broja svojti (EPT), kao i udjela EPT jedinki u zajednici bentoskih makrobeskralješnjaka (EPT[%]) te metala otopljenih u vodi i fizikalno-kemijskih pokazatelja. Prisustvo EPT zajednice s velikim brojem svojti i velikim udjelom u ukupnoj zajednici bentoskih makrobeskralješnjaka se obično povezuje s dobrom kvalitetom slatkovodnih ekosustava. Svi podaci su prikupljeni u sklopu programa sustavnog praćenja stanja površinskih voda tijekom 8 godina (2010.-2017.). Ukupno je analizirano 247 uzoraka bentoskih makrobeskralješnjaka na 172 postaje uzorkovanja, a svi uzorci prikupljeni su koristeći AQEM metodu uzorkovanja. Voda za određivanje koncentracije otopljenih metala i osnovnih fizikalno-kemijskih pokazatelja uzorkovana je u godini kad je prikupljen uzorak bentoskih makrobeskralješnjaka, a svi navedeni pokazatelji mjereni su standardnim analitičkim metodama za analizu kakvoće površinskih voda (ISO norme). Pronađena je negativna veza EPT zajednice (broj svojti vodencvjetova (E), obalčara (P), tulara (T) i ukupno (EPT), te udio jedinki EPT u ukupnom uzorku (EPT [%]) s fizikalno-kemijskim pokazateljima, kao što su to npr.: temperatura i P = -0,528, električna vodljivost i P = -0,491, ukupna tvrdoća i EPT = -0,493) te slaba negativna veza s alkalitetom i ukupnom suspendiranom tvari. Spearmanov koeficijent korelacije ukazuje i na statistički značajnu negativnu povezanost između i koncentracije mangana s P i T (-0,540, -0,380 slijedom) te arsena s EPT[%] (-0,421). S ostalim metalima (bakar, cink, kadmij, krom, nikal, olovo, živa i željezo) korelacije su slabe do beznačajne. Rezultati ovog istraživanja ukazuju da bi uporaba EPT kao bioindikatora mogla biti važna strategija pri određivanju zagađenja manganom i arsenom u vodenom okolišu.The paper investigates the relationship between the number of taxa within three orders of aquatic insects - Ephemeroptera (mayflies), Plecoptera (stoneflies) and Trichoptera (caddisflies), the total taxa (EPT) and EPT individuals in the benthic macroinvertebrate community (EPT[%]), including dissolved metals in the water and physico-chemical parameters. The presence of EPT community with numerous taxa and a large share in the total macroinvertebrate community is usually associated with good water quality of freshwater ecosystems. All collected data used in this study originate from the national monitoring programme of surface water quality within a period of 8 years (2010 - 2017). In total, 247 samples of benthic macroinvertebrates from 172 sampling stations were analysed. All samples were collected according to the AQEM sampling protocol. The water used for determining the concentrations of dissolved metals and basic physico-chemical parameters was sampled in the same year when the samples of macrozoobenthos were collected, and all mentioned parameters were measured according to standard analytical methods for analysing surface water quality (ISO standards). The statistical analysis showed a significant negative correlation of the EPT assemblage (number of taxa of Ephemeroptera (E), Plecoptera (P), Trichoptera (T) and altogether (EPT), as well as the share of EPT individuals in the sample (EPT [%]) with physico-chemical parameters, such as temperature and (P) = -0.528, electric conductivity and (P) = -0.485, total hardness and EPT = -0.493, including a weak negative correlation with alkalinity and total suspended solids. The Spearman\u27s coefficient of the correlation indicated a statistically significant negative correlation of Manganese with P and T (-0.540 and -0.380, respectively) and of Arsenic with EPT[%] (-0.421). The correlations with other metals (Copper, Zinc, Cadmium, Chrome, Nickel, Lead, Mercury and Iron) were weak to insignificant. The results of the present study suggest that the use of EPT as bioindicators may be an important strategy for detecting Manganese and Arsenic pollution in aquatic environments.In diesem Artikel wurde das Verhältnis untersucht zwischen der Anzahl von Taxa innerhalb drei Ordnungen von Insekten, nämlich Eintagsfliegen (Ephemeroptera), Steinfliegen (Plecoptera) und Köcherfliegen (Trichoptera), der Gesamtzahl von Taxa (EPT), dem Anteil der EPT-Individuen in der Gemeinschaft von Makrozoobenthos (EPT[%]) sowie im Wasser gelösten Metallen und den physikalischen und chemischen Indikatoren. Die Anwesenheit der EPT-Gemeinschaft mit einer großen Anzahl von Taxa und großem Anteil an der Gesamtgemeinschaft von Makrozoobenthos verbindet man gewöhnlich mit sehr guter Qualität von Süßwasserökosystemen. Alle Daten wurden im Rahmen des Programms zur systematischen Überwachung des Zustandes von Oberflächengewässern im Laufe von acht Jahren (2010-2017) gesammelt. Insgesamt wurden 247 Makrozoobenthosproben von 172 Probenstationen analysiert, wobei alle Proben nach der AQEM-Methode gesammelt wurden. Die Wasserproben zur Bestimmung der Konzentration von im Wasser gelösten Metallen und den physikalischen und chemischen Indikatoren wurden im gleichen Jahr wie die Makrozoobenthosproben entnommen. Alle Indikatoren wurden mit den üblichen Methoden zur Analyse der Qualität von Oberflächengewässern (ISO-Normen) gemessen. Der negative Zusammenhang zwischen der EPT-Gemeinschaft (Anzahl von Taxa von Eintagsfliegen (E), Steinfliegen (P), Köcherfliegen (T) und Gesamtzahl (EPT) sowie dem Anteil der EPT-Individuen in der Gesamtprobe (EPT[%]) und den physikalischen und chemischen Indikatoren, z. B. Temperatur und P = -0,528, elektrische Leitfähigkeit und P = -0,491, Gesamthärte und EPT = -0,493 wurde festgestellt sowie der schwache negative Zusammenhang zur Alkalität und Gesamtschwebestoffen. Der Spearman-Korrelationskoeffizient weist auf einen statistisch signifikanten negativen Zusammenhang zwischen der Mangankonzentration und P und T (-0,540 bzw. -0,380) und der Arsenkonzentration und EPT[%] (-0,421) hin. Bei anderen Metallen (Kupfer, Zink, Cadmium, Nickel, Blei, Quecksilber und Eisen) sind die Korrelationen schwach bis insignifikant. Die Ergebnisse dieser Untersuchung zeigen, dass die Anwendung von EPT als Bioindikator eine wichtige Strategie in der Bestimmung von Mangan- und Arsenverschmutzung in Gewässern sein könnte

Der Einfluss von physikalischen und chemischen Indikatoren und Metallen auf die Gemeinschaften von Eintagsfliegen, Steinfliegen und Köcherfliegen (EPT)

U ovom smo radu istraživali vezu između broja svojti unutar triju redova vodenih kukaca: vodencvjetova (Ephemeroptera), obalčara (Plecoptera) i tulara (Trichoptera), ukupnog broja svojti (EPT), kao i udjela EPT jedinki u zajednici bentoskih makrobeskralješnjaka (EPT[%]) te metala otopljenih u vodi i fizikalno-kemijskih pokazatelja. Prisustvo EPT zajednice s velikim brojem svojti i velikim udjelom u ukupnoj zajednici bentoskih makrobeskralješnjaka se obično povezuje s dobrom kvalitetom slatkovodnih ekosustava. Svi podaci su prikupljeni u sklopu programa sustavnog praćenja stanja površinskih voda tijekom 8 godina (2010.-2017.). Ukupno je analizirano 247 uzoraka bentoskih makrobeskralješnjaka na 172 postaje uzorkovanja, a svi uzorci prikupljeni su koristeći AQEM metodu uzorkovanja. Voda za određivanje koncentracije otopljenih metala i osnovnih fizikalno-kemijskih pokazatelja uzorkovana je u godini kad je prikupljen uzorak bentoskih makrobeskralješnjaka, a svi navedeni pokazatelji mjereni su standardnim analitičkim metodama za analizu kakvoće površinskih voda (ISO norme). Pronađena je negativna veza EPT zajednice (broj svojti vodencvjetova (E), obalčara (P), tulara (T) i ukupno (EPT), te udio jedinki EPT u ukupnom uzorku (EPT [%]) s fizikalno-kemijskim pokazateljima, kao što su to npr.: temperatura i P = -0,528, električna vodljivost i P = -0,491, ukupna tvrdoća i EPT = -0,493) te slaba negativna veza s alkalitetom i ukupnom suspendiranom tvari. Spearmanov koeficijent korelacije ukazuje i na statistički značajnu negativnu povezanost između i koncentracije mangana s P i T (-0,540, -0,380 slijedom) te arsena s EPT[%] (-0,421). S ostalim metalima (bakar, cink, kadmij, krom, nikal, olovo, živa i željezo) korelacije su slabe do beznačajne. Rezultati ovog istraživanja ukazuju da bi uporaba EPT kao bioindikatora mogla biti važna strategija pri određivanju zagađenja manganom i arsenom u vodenom okolišu.The paper investigates the relationship between the number of taxa within three orders of aquatic insects - Ephemeroptera (mayflies), Plecoptera (stoneflies) and Trichoptera (caddisflies), the total taxa (EPT) and EPT individuals in the benthic macroinvertebrate community (EPT[%]), including dissolved metals in the water and physico-chemical parameters. The presence of EPT community with numerous taxa and a large share in the total macroinvertebrate community is usually associated with good water quality of freshwater ecosystems. All collected data used in this study originate from the national monitoring programme of surface water quality within a period of 8 years (2010 - 2017). In total, 247 samples of benthic macroinvertebrates from 172 sampling stations were analysed. All samples were collected according to the AQEM sampling protocol. The water used for determining the concentrations of dissolved metals and basic physico-chemical parameters was sampled in the same year when the samples of macrozoobenthos were collected, and all mentioned parameters were measured according to standard analytical methods for analysing surface water quality (ISO standards). The statistical analysis showed a significant negative correlation of the EPT assemblage (number of taxa of Ephemeroptera (E), Plecoptera (P), Trichoptera (T) and altogether (EPT), as well as the share of EPT individuals in the sample (EPT [%]) with physico-chemical parameters, such as temperature and (P) = -0.528, electric conductivity and (P) = -0.485, total hardness and EPT = -0.493, including a weak negative correlation with alkalinity and total suspended solids. The Spearman\u27s coefficient of the correlation indicated a statistically significant negative correlation of Manganese with P and T (-0.540 and -0.380, respectively) and of Arsenic with EPT[%] (-0.421). The correlations with other metals (Copper, Zinc, Cadmium, Chrome, Nickel, Lead, Mercury and Iron) were weak to insignificant. The results of the present study suggest that the use of EPT as bioindicators may be an important strategy for detecting Manganese and Arsenic pollution in aquatic environments.In diesem Artikel wurde das Verhältnis untersucht zwischen der Anzahl von Taxa innerhalb drei Ordnungen von Insekten, nämlich Eintagsfliegen (Ephemeroptera), Steinfliegen (Plecoptera) und Köcherfliegen (Trichoptera), der Gesamtzahl von Taxa (EPT), dem Anteil der EPT-Individuen in der Gemeinschaft von Makrozoobenthos (EPT[%]) sowie im Wasser gelösten Metallen und den physikalischen und chemischen Indikatoren. Die Anwesenheit der EPT-Gemeinschaft mit einer großen Anzahl von Taxa und großem Anteil an der Gesamtgemeinschaft von Makrozoobenthos verbindet man gewöhnlich mit sehr guter Qualität von Süßwasserökosystemen. Alle Daten wurden im Rahmen des Programms zur systematischen Überwachung des Zustandes von Oberflächengewässern im Laufe von acht Jahren (2010-2017) gesammelt. Insgesamt wurden 247 Makrozoobenthosproben von 172 Probenstationen analysiert, wobei alle Proben nach der AQEM-Methode gesammelt wurden. Die Wasserproben zur Bestimmung der Konzentration von im Wasser gelösten Metallen und den physikalischen und chemischen Indikatoren wurden im gleichen Jahr wie die Makrozoobenthosproben entnommen. Alle Indikatoren wurden mit den üblichen Methoden zur Analyse der Qualität von Oberflächengewässern (ISO-Normen) gemessen. Der negative Zusammenhang zwischen der EPT-Gemeinschaft (Anzahl von Taxa von Eintagsfliegen (E), Steinfliegen (P), Köcherfliegen (T) und Gesamtzahl (EPT) sowie dem Anteil der EPT-Individuen in der Gesamtprobe (EPT[%]) und den physikalischen und chemischen Indikatoren, z. B. Temperatur und P = -0,528, elektrische Leitfähigkeit und P = -0,491, Gesamthärte und EPT = -0,493 wurde festgestellt sowie der schwache negative Zusammenhang zur Alkalität und Gesamtschwebestoffen. Der Spearman-Korrelationskoeffizient weist auf einen statistisch signifikanten negativen Zusammenhang zwischen der Mangankonzentration und P und T (-0,540 bzw. -0,380) und der Arsenkonzentration und EPT[%] (-0,421) hin. Bei anderen Metallen (Kupfer, Zink, Cadmium, Nickel, Blei, Quecksilber und Eisen) sind die Korrelationen schwach bis insignifikant. Die Ergebnisse dieser Untersuchung zeigen, dass die Anwendung von EPT als Bioindikator eine wichtige Strategie in der Bestimmung von Mangan- und Arsenverschmutzung in Gewässern sein könnte

Construction of a heart rate sensor using the Arduino platform

U radu je prikazan eksperimentalni uređaj za mjerenje frekvencije srca koji funkcionira na principu transmisijske i refleksijske fotopletizmografije u spektru vidljive svjetlosti. Glavne komponente uređaja korištenog u istraživanju su platforma Arduino Uno i senzor KY-018 Fotowiderstand Modul. U eksperimentu su korištene različite konfiguracije uređaja, a za potrebe njegovog rada napisan je programski kod u programskom jeziku C za softverski integrirano razvojno okruženje Arduino. Broj otkucaja srca određen je upotrebom različitih izvora svjetlosti. Podaci su iz uređaja Arudino Uno očitani bez i uz upotrebu algoritma. Valjanost dobivenih podataka provjerena je pomoću pametnog mobitela sa senzorom za mjerenje otkucaja srca. Zaključeno je da su najbolji rezultati mjerenja dobiveni u slučaju svjetlosti koja se najmanje apsorbira u tkivu i koja je jačeg intenziteta. Na kraju rada ukazano je na neka ograničenja i mogućnosti poboljšanja uređaja.The paper presents an experimental device for measuring heart rate that works on the principle of transmission- and reflectance-mode photoplethysmography in the spectrum of visible light. The main components of the device used in the research are the Arduino Uno platform and the KY-018 Fotowiderstand Module sensor. Different configurations of the device were used in the experiment and, for the purpose of its functioning, the program code was written in the C programming language for the integrated development environment Arduino. The heart rate was determined using different light sources. Data were taken from the Arudino Uno device without and with the use of the algorithm. The validity of the obtained data was checked using a smartphone with a heart rate sensor. It was concluded that the best measurement results were obtained in the case of light that is least absorbed in the tissue and which is of stronger intensity. At the end of the paper, some limitations and possibilities for improving the device were pointed out

Construction of a heart rate sensor using the Arduino platform

U radu je prikazan eksperimentalni uređaj za mjerenje frekvencije srca koji funkcionira na principu transmisijske i refleksijske fotopletizmografije u spektru vidljive svjetlosti. Glavne komponente uređaja korištenog u istraživanju su platforma Arduino Uno i senzor KY-018 Fotowiderstand Modul. U eksperimentu su korištene različite konfiguracije uređaja, a za potrebe njegovog rada napisan je programski kod u programskom jeziku C za softverski integrirano razvojno okruženje Arduino. Broj otkucaja srca određen je upotrebom različitih izvora svjetlosti. Podaci su iz uređaja Arudino Uno očitani bez i uz upotrebu algoritma. Valjanost dobivenih podataka provjerena je pomoću pametnog mobitela sa senzorom za mjerenje otkucaja srca. Zaključeno je da su najbolji rezultati mjerenja dobiveni u slučaju svjetlosti koja se najmanje apsorbira u tkivu i koja je jačeg intenziteta. Na kraju rada ukazano je na neka ograničenja i mogućnosti poboljšanja uređaja.The paper presents an experimental device for measuring heart rate that works on the principle of transmission- and reflectance-mode photoplethysmography in the spectrum of visible light. The main components of the device used in the research are the Arduino Uno platform and the KY-018 Fotowiderstand Module sensor. Different configurations of the device were used in the experiment and, for the purpose of its functioning, the program code was written in the C programming language for the integrated development environment Arduino. The heart rate was determined using different light sources. Data were taken from the Arudino Uno device without and with the use of the algorithm. The validity of the obtained data was checked using a smartphone with a heart rate sensor. It was concluded that the best measurement results were obtained in the case of light that is least absorbed in the tissue and which is of stronger intensity. At the end of the paper, some limitations and possibilities for improving the device were pointed out