Sezonski trendovi drifta i bentosa na mahovinom prekrivenim sedrenim barijerama unutar krškog baražnog hidrosustava (Plitvička jezera, Hrvatska)

Macroinvrtebrate drift and streambed material transport are very important for the redistribution of energy sources and habitat-building elements within lotic ecosystems. The objective of the present study was to examine seasonal drift-benthos trends of macroinvertebrates and organic/inorganic matter particles between barrier and pool habitats at a small spatial scale within a karst barrage hydrosystem (Plitvice Lakes). Benthos and drift were sampled seasonally between November 2006 and July 2007 at four sampling sampling sites representing barrier (B; fast-flow velocity) and pool (P; slow-flow velocity) habitats. During the entire study period, amounts of drifting macroinvertebrates, and organic and inorganic particles were significantly higher at barriers than in pools. In benthos, such barrier trend was found for moss only. Considering seasonal differences, benthos showed no significant trends, whereas in drift we found significantly higher loads of all measured items in autumn and winter than in other two seasons, but such trend was observed at barriers only. The quantities of organisms in benthos and drift greatly followed the respective trends of particulate organic and inorganic matter, especially moss. At both habitat types macroinvertebrate drift mostly presented a smaller proportion of total benthos faunal composition, although there were some taxa that occurred in drift or benthos only. In total (including benthos and drift samples), we found 63 taxa during the study - 5 of them were found only within pools, 38 only at barriers and 20 of them were found at both habitat types. The most dominant in both benthos and drift, were Oligochaeta, cladoceran Alona spp., Copepoda, and larval stages of coleopteran Riolus spp. and dipteran Simulium spp. Most of them belong to mobile, epiphytic and/or interstitial detritivores that most likely originated from the submerged aquatic vegetation (i.e., moss), floating leaf litter and/or sediments along our study reach, whereas cladoceran and copepod taxa likely originated from the upstream lake. The observed seasonality in the faunal drift-benthos composition (e.g., Cladocera increase in summer and autumn, Ephemeroptera decrease/absence in winter and spring), was likely a consequence of the seasonal food sourcing for individual taxa, and their particular life history traits. Our findings suggest that within the tufa-precipitating Plitvice Lakes hydrosystem: a) drift has a very important role in maintaining benthos structure and stability within the barrier and pool habitats; b) tufa barriers are highly dynamic habitats, characterized by pronounced season-specific dislodgement of the benthic organisms and particulate matter, and effective moss-mediated macroinvertebrate dispersal; c) the abundance of macroinvertebrates and the amounts of organic/inorganic particles in drift are influenced not only by flow velocity and the seasonal lake discharges/biocommunity dynamics, but also by the initial distribution of particles/organisms within benthos as well as by the life history traits of the individual benthic organisms.Nizvodno otplavljivanje (drift) bentoskih makrobeskralježnjaka i supstrata je važan mehanizam (pre)raspodjele energetskih izvora i građevnih elemenata staništa u lotičkim ekosustavima. Cilj ovog istraživanja bio je istražiti sezonske trendove drifta i bentosa na barijerama i u ujezerenjima na maloj prostornoj skali unutar krškog baražnog hidrosustava Plitvičkih jezera. Uzorkovanje makrobeskralježnjaka i usitnjene organske/anorganske tvari u driftu i bentosu provedeno je sezonski između studenog 2006. i srpnja 2007. na četiri postaje, koje su predstavljale dva tipa staništa: barijere (B; staništa s brzom strujom vode) i ujezerenja (P; staništa sa sporom strujom vode). Tijekom cijelog razdoblja istraživanja, ukupna brojnost makrozoobentosa i količina organskih/anorganskih tvari u driftu bile su značajno više na barijerama nego ujezerenjima. U bentosu je takva razlika među tipovima staništa opažena samo s obzirom na količinu mahovina. S obzirom na sezonske razlike, u bentosu nisu opažene značajnije trendovi, dok su u driftu u jesen i zimu nađene značajno veće količine organske i anorganske tvari i organizama nego u preostale dvije sezone, ali takav je trend opažen samo na barijerama. Brojnost organizama u bentosu i driftu uvelike je slijedila trendove količina usitnjene organske i anorganske tvari, osobito mahovina. U oba tipa staništa, taksonomski sastav drifta uglavnom je odražavao sastav bentosa. Međutim, u driftu su pronađeni organizmi koji nisu bili zastupljeni u bentosu i obrnuto. Ukupno tijekom istraživanja nađene su 63 svojte u uzorcima bentosa i drifta – od toga je 5 svojti nađeno samo u ujezerenjima, 38 samo na barijerama, a 20 svojti na oba tipa staništa. Najdominantniji i u bentosu i u driftu bili su Oligochaeta, rašljoticalac Alona spp., Copepoda te ličinke kornjaša Riolus spp. i dvokrilaca Simulium spp. Većina njih pripada mobilnim, epifitskim i/ili intersticijskim detritivorima, za koje pretpostavljamo da na našim postajama istraživanja dolaze na podvodnoj vegetaciji (tj. mahovini), plutajućim listovima i/ili u samom supstratu, dok za predstavnike Cladocera i Copepoda smatramo da potječu iz uzvodnog jezera. Opažene sezonske trendove u taksonomskom sastavu drifta i bentosa (npr. povećanje brojnosti Cladocera u ljeto i jesen; smanjenje brojnosti/odsutnost Ephemeroptera u proljeće i zimu) objašnjavamo kao posljedicu sezonskih razlika u izvorima hrane i životnim ciklusima pojedinih svojti. Naši rezultati ukazuju da u sedrotvornom sustavu Plitvičkih jezera: a) drift ima vrlo važnu ulogu u održavanju strukture i stabilnosti bentosa na različitim tipovima staništa (na barijerama i u ujezerenjima); b) sedrene barijere su vrlo dinamična staništa, u kojima je snažno izraženo sezonsko otplavljivanje bentoskih organizama i usitnjene organske/anorganske tvari, a osobito mahovina kojima se može pripisati vrlo važna uloga prijenosnika pri nizvodnom transportu tvari i organizama; c) na brojnost makrozoobentosa i količinu organskih/anorganskih tvari u driftu, izuzev brzine strujanja vode i sezonskih razlika u jezerskom utjecaju (tj. jezerskom protoku i životnim zajednicama), u velikoj mjeri utječu i inicijalni sastav i raspodjela čestica/organizama u bentosu te ekološko-etološke osobitosti pojedinih skupina organizama

Kratkoročni učinci prirodnog protoka na kvalitetu vode duž dva urbana potoka – pilot-istraživanje

In this pilot-study, we investigated the short-term effects of natural stream discharge on the stream water quality at six sites located along the two urban streams - Bliznec (B) and Veliki potok (VP) - flowing through Zagreb, capital of Croatia. The streams source within the Medvednica Nature Park (upper stream reaches) and flow along an increasing urban gradient in central Zagreb region (middle and lower stream reaches). The following physico-chemical parameters were measured every other day over the two-week period in October 2017: stream discharge, water temperature and oxygen concentration, conductivity, pH, chemical oxygen demand (CODKMnO4), and in-stream concentrations of nutrients (nitrites, nitrates, orthophosphates). Nutrients were the most variable parameters during the two-week period. Bliznec generally showed significantly higher discharge and oxygen levels compared to Veliki potok, which had significantly higher CODKMnO4 and nitrite concentrations. Middle and lower stream reaches had significantly higher temperature, nitrite and nitrate concentrations in comparison to the upper reaches. Several physico-chemical parameters (discharge, nitrites, nitrates, orthophosphates, conductivity and CODKMnO44) evidenced to be highly synchronized between the two streams, among the three stream reaches and among the six sites over time, which was corroborated by relatively high proxy for temporal concordance (τ > 0.60) of these parameters. This indicated that environmental conditions (stream water quality) synchronously vary across space and over time along our study streams. The data also revealed significant between-site and temporal changes of the physico-chemical parameters after a major storm event. Moreover, conductivity was found to correlate with discharge. Findings of the present pilot study indicate that urban streams are very dynamic ecosystems showing an increased sensitivity to environmental changes, such as anthropogenic influences and local weather conditions. We suggest that the extensive environmental variability of urban streams should be considered in the scope of ecological studies and environmental management approaches within urban zones.U ovom pilot-istraživanju istražili smo kratkoročne učinke prirodnog protoka na kakvoću vode na šest postaja smještenih duž dva urbana potoka - Blizneca (B) i Velikog potoka (VP) - koji protječu kroz Zagreb, glavni grad Hrvatske. Potoci izviru unutar Parka prirode Medvednica (gornji tok) i teku duž rastućeg urbanog gradijenta, kroz središnji dio Zagreba (srednji i donji tok). Svaki drugi dan tijekom dva tjedna u listopadu 2017. mjereni su sljedeći fizičko-kemijski parametri za vodu: protok, temperatura vode i koncentracija kisika, konduktivitet, pH, kemijska potrošnja kisika (KPKKMnO4) i koncentracija hranjivih soli (nitrita, nitrata, ortofosfata) u vodi. Najvarijabilniji parametri tijekom dva tjedna bile su koncentracije hranjivih soli. Bliznec je općenito pokazao značajno više vrijednosti protoka i koncentracije kisika u odnosu na Veliki potok, koji je imao značajno više vrijednosti KPKKMnO4 i koncentracije nitrita. Srednji i donji dijelovi toka oba potoka imali su značajno više temperature te koncentracije nitrita i nitrata u odnosu na gornji tok. Nekoliko fizičko-kemijskih parametara (protok, koncentracije nitrita, nitrata i ortofosfata, konduktivitet i KPKKMnO4) pokazali su veliku podudarnost vremenskih trendova između dva potoka, između tri dijela toka i između šest postaja, što je i dokazano relativno visokim koeficijentom (τ > 0.60) koji ukazuje na vremensko podudaranje parametara. To je nadalje ukazalo da se okolišni uvjeti (kakvoća vode) duž naših potoka ujednačeno mijenjaju u prostoru i vremenu. Podaci su također ukazali na značajne promjene mjerenih fizikalno-kemijskih parametara nakon nevremena (razdoblja povišenog protoka vode). Nadalje, korelacijskom analizom je utvrđeno da konduktivitet značajno ovisi o protoku. Rezultati ovog pilot-istraživanja pokazuju da su urbani potoci vrlo dinamični ekosustavi koji pokazuju povećanu osjetljivost na promjene u okolišu, kao što su antropogeni utjecaji i lokalni vremenski uvjeti. Predlažemo da se u okviru ekoloških studija i pri upravljanju okolišem unutar urbanih zona uzme u obzir značajna ekološka varijabilnost urbanih vodotoka

Determinants of manufacturing industry exports in European Union member states: a panel data analysis

This paper aims to provide analysis on the determinants of export performance on the extensive data-set of the 27 European Union member states’ total manufacturing and high tech manufacturing industry. Hence, this paper adds to the existing empirical work by specifying an export performance equation not only as a function of income and price, as is traditionally done, but also industrial production and labour cost. For that purpose, dynamic panel data models are estimated by utilising the system GMM estimator for the period from 2000 to 2011. The obtained results indicate that both industrial production and domestic demand have a positive and statistically significant impact on total and high tech manufacturing exports. On the other hand, it is proven that foreign demand also has an impact on total manufacturing exports. Thus, the paper’s contribution is reflected in the acknowledgement that a stable macroeconomic environment (contained in the significance of a dummy variable for the economic crisis in both models), boosting production capacity and domestic demand, is essential for better export performance and the competitiveness of the manufacturing industry in an increasingly competitive global economic climate. Finally, from the perspective of policy-making, the paper concludes that recovery in the manufacturing industry could be the much needed push from crisis to economic development

Urban streams – accessible habitats for conducting ecological research within natural science and biology school classes

Širenjem urbanih zona i povećanjem broja urbanog stanovništva, gradovi su postali najveći izvori onečišćenja. Suvremeni urbani sadržaji povećavaju kvalitetu života gradskog stanovništva, međutim mijenjaju prirodno stanje okoliša. Stoga se u suvremenoj biologiji počela isticati urbana ekologija - jedna od novijih disciplina presudna za urbanizam i urbanističko planiranje, koja omogućuje procjenu stanja okoliša u gradovima te provedbu sustavnog nadzora, u svrhu očuvanja i zaštite gradskih ekosustava, uključujući i urbane vodotoke. U ovom radu navodimo primjer istraživanja urbanih potoka u kojem se razmatraju razmjeri i moguće posljedice urbanih utjecaja na ekologiju vodenih ekosustava i koje može poslužiti kao osnova za objašnjavanje osnovnih ekoloških koncepata i sadržaja, kao što su struktura bioloških zajednica, hranidbene mreže, oligotrofija ili eutrofija, ekološka valencija i rasprostranjenost organizama, ekološka niša. Nadalje, povezivanjem tematike urbane ekologije s problematikom ugroženosti vodnih resursa te korištenjem urbanih potoka kao modelnih staništa za istraživanje ekoloških tema (i usvajanje ekoloških koncepata) u nastavi Prirode i Biologije, učenike se (osim važnih ekoloških koncepata) upoznaje i sa suvremenom ideologijom „zelenog rasta“, „zelenih“ gradova, održivog razvoja, zaštite okoliša te regionalnog razvoja. Opisano istraživanje primjereno je za učenike viših razreda osnovne škole (Biologija 7 i 8) i/ili za učenike srednjih škola (u vidu kratkoročnog i/ili dugoročnog ekološkog istraživanja urbanih potoka u neposrednoj blizini škole i/ili životne sredine učenika), a može se prilagoditi i za učenike mlađeg uzrasta.Predstavljeno istraživanje uključuje istraživanje ekološkog stanja urbanih potoka kroz praćenje: (i) kakvoće vode (fizičko-kemijskih svojstava vode); (ii) sastava vodene faune koja čini osnovu hranidbenih lanaca u vodenim ekosustavima (bentoskih makrobeskralježnjaka i organizama obraštaja); (iii) dinamike transporta (nizvodnog otplavljivanja) organizama u urbanim vodotocima; (iv) biotičkog indeksa na osnovu primijećenih makrobeskralježnjaka kao informaciji o onečišćenju vodotoka. Važno je napomenuti da odabrane aktivnosti mogu biti primijenjene u istraživanju osnovnih bioloških pokazatelja svih, a ne samo urbanih, vodenih ekosustava. U tom smislu, opisana metodologija može biti prilagođena i primijenjena za slična istraživanja ostalih tipova tekućica dostupnih učenicima. Pri provedbi aktivnosti, potiče se korištenje Priručnika za voditelje programa GLOBE, koji je dostupan na poveznici http://globe.pomsk.hr/prirucnik.htm, i kojim se već služi i više od stotinu hrvatskih škola uključenih u GLOBE mrežu, ali se predlažu i novije (kvantitativne) metode uzorkovanja makrobeskralježnjaka i organizama obraštaja, kao i pojednostavljeni ključevi za taksonomsku determinaciju organizama primjenjivi u nastavi Prirode i Biologije.By expanding urban zones and increasing the urban population, cities have become the largest source of pollution. Contemporary urban activities increase the quality of life of the city\u27s population, and they change the natural state of the environment. Therefore, urban ecology has emerged in modern biology - one of the newer disciplines crucial for urbanism and urban planning, which enables the assessment of environmental status in cities and the implementation of systematic monitoring for the purpose of preserving and protecting urban ecosystems, including urban watercourses. In this paper we present an example of a research dealing with urban streams, i.e., exploring the scale and possible consequences of urban impacts on ecology of aquatic ecosystems and likely serving as a basis for explaining basic ecological concepts and contents such as the structure of biological communities, nutritional network, oligotrophy. Furthermore, by linking urban ecology topic with the problem of endangered water resources, and using urban streams as model habitats to explore ecological themes (and concepts) in natural science and biology school classes, pupils (besides important ecological concepts) meet the modern ideology of "green growth", "green" cities, sustainable development, environmental protection and regional development. Described study is appropriate for upper secondary school students (Biology 7 and 8) and/or secondary school students (in form of short- and/or long-term ecological survey of urban streams close to school/student environment). It includes the investigation of ecological status of urban streams through monitoring: (i) water quality (physical-chemical properties of water); (ii) the composition of aquatic fauna, which forms the basis of feeding chains in aquatic ecosystems (benthic macroinvertebrates and periphytic organisms); (iii) dynamics of transport (downstream drift) of organisms in urban watercourses; (iv) a biotic index based on observed macroinvertebrates as water contamination information. It is important to note that selected activities can be applied in exploring basic biological indicators of all - not just urban - aquatic ecosystems. In this respect, the methodology described may be adapted and applied for similar research of other types of aquatic habitats (i.e., running waters) available to students. In the implementation of the activities, it is encouraged to use the GLOBE Leaders Manual, available at http://globe.pomsk.hr/prirucnik.htm, which is already used by more than one hundred Croatian schools involved in the GLOBE network. However, we also propose newer (quantitative) sampling methods for macroinvertebrates and periphytic organisms, as well as simplified taxonomic keys for organisms to be applied in natural science and biology school classes

Sources of learning eleven years old elementary school students in Science class

Cilj istraživanja bio je dobiti uvid u navike upotrebe različitih dodatnih izvora znanja/informacija prilikom učenja nastavnih sadržaja iz predmeta Priroda učenika petog razreda osnovne škole obzirom na spol, veličinu mjesta stanovanja, zaključnu ocjenu iz predmeta Prirode i društva u 4. razredu osnovne škole te korištene nastavne metode i strategije na satu Prirode. U istraživanju je sudjelovalo 930 učenika petih razreda iz 28 škola iz cijele Hrvatske. Učenici su putem online ankete trebali odabrati dodatni izvor znanja koji najčešće koriste kada im nešto nije jasno prilikom učenja nastavnih sadržaja iz predmeta Priroda. Prilikom obrade nastavnih tema učenici su učili kolaborativnim istraživačkim učenjem, istraživačkim učenjem ili tradicionalnim oblikom učenja. Rezultati su pokazali kako je odabrani način učenja utječe na učenički odabir izvora učenja uz obrnuto proporcionalan odnos i povećanje korištenja komunikacijskih izvora (učitelj, prijatelji, roditelj) u odnosu na individualne izvore (udžbenik, bilježnica, Internet), u skladu s povećanjem neposrednog učenja, a time i neovisnosti učenja. Udžbenik i dalje glavni izvor informacija prilikom učenja, ali kolaborativno istraživačko učenje potiče uz korištenje Interneta i raznovrsnije korištenje ostalih izvora učenja. Rezultati upućuju na to kako je izuzetno važno prilikom planiranja poučavanja odabrati način učenja koji će učenicima alfa generacije omogućiti dinamičnost prilikom učenja i slobodu odabira strategija učenja i rješavanja problema.The research aimed to gain an insight into the habits of using different additional sources of knowledge/information when learning teaching content from the Science subject. From 28 elementary schools all over Croatia, 930 students participated in the research. Fifth-grade students’ opinions were analysed with regard to gender, size of place of residence, the final grade from the Science and Society subject in the 4th grade of elementary school, and the used teaching methods and strategies in the Science lesson. Through an online survey, students were supposed to choose an additional source of knowledge that they use most often when something is not clear to them when learning the teaching content of the Science subject. When processing the teaching topics, the students learned through collaborative discovery learning, discovery learning or a traditional form of learning. The results showed that the chosen learning method affects the student\u27s choice of learning sources with an inversely proportional relationship and an increase in the use of communication sources (teacher, friends, parents) in relation to individual sources (textbook, notebook, Internet), in accordance with the increase in direct learning, and thus the independence of learning. The textbook is still the main source of information when learning, but collaborative research learning is encouraged along with the use of the Internet and more varied use of other learning sources. The results indicate that it is extremely important when planning to teach to choose a learning method that will enable students of the alpha generation to be dynamic during learning and have the freedom to choose learning strategies and problem solving

Influence of student interest and non-stimulated self-regulated learning on the learning outcomes associated to the topic soil structure and properties

Za uspješno savladavanje gradiva pri poučavanju, neophodno je pobuditi interes učenika za kontekst poučavanja izborom prikladnih aktivnosti učenja. Pri tome je vrlo važan i odnos učenika prema učenju te način kako samostalno uče nakon početnog učenja u školi. Ovo istraživanje usmjereno je na ispitivanje povezanosti: (i) početne zainteresiranosti učenika za teme vezane uz tematsku cjelinu Tlo, (ii) strategija učenja koje učenici koriste tijekom učenja i (iii) uspjeha na pisanoj provjeri znanja provedenoj na kraju obrađene tematske cjeline Tlo. Istraživanje je provedeno u dva odjeljenja petog razreda III. Osnovne škole Varaždin na 43 učenika. Istraživanje je pokazalo kako su učenici u dobi od 11 godina izrazito zainteresirani za učenje tema vezanih uz Tlo te su učenici koji su slabije riješili ispit, kao i oni učenici koji su ga riješili vrlo uspješno na početku učenja, iskazali jednaku zainteresiranost za učenje o tlu. Učenici koji intuitivno samostalno sistematiziraju gradivo uz namjeru uočavanja povezivanja, prepoznaju primjenu svog znanja u aktivnostima poput projekata te imaju visoku intrinzičnu motivaciju za učenje Prirode i trude se biti uspješni na nastavi, čak i ako im se ne sviđa ono što uče. Za razliku od njih, učenici koji uspješno rješavaju samo zadatke reproduktivnog karaktera nisu skloni povezivanju svog znanja i često uče napamet. Također učenici usmjereni na reproduktivno učenje ne prepoznaju da aktivnosti provedene tijekom učenja i poučavanja mogu poslužiti kao osnova s kojom mogu povezati ranije obrađena znanja. Za potrebe poticanja učenika na razmišljanje i samoregulirajuće učenje, s učenicima bi se trebale češće provoditi aktivnosti u kojima se traži argumentirano povezivanje stečenog znanja pri generiranju objašnjenja.To successfully master the learning objectives, it is necessary to arouse students\u27 interest in the context of teaching, by choosing appropriate teaching activities. Thereby, the attitude of students towards learning and the way they learn independently after the initial learning in school is also very important. This study focuses on examining the relationship between: (i) students\u27 initial interest in topics related to the Soil unit, (ii) learning strategies used by students during learning, and (iii) success in the written exam conducted at the end of the Soil unit. The study was conducted in two departments of the fifth grade in the III. Elementary school Varaždin with 43 students. The research showed that 11-year-old students are extremely interested in learning about soil-related topics. Students who had low success in the written exam, as well as those who excelled at the exam at the beginning of learning, showed equal interest in learning about soil. Students who intuitively systematize the learning material to notice connections, recognize the application of their knowledge in activities such as projects and have a high intrinsic motivation to learn Nature and strive to be successful in learning, even if they do not like what they learn. In contrast, students who successfully solve only reproductive tasks, do not tend to connect their knowledge and often learn by heart. Also, students focused on reproductive learning do not recognize that activities carried out during teaching and learning can serve as a basis for relating previously processed knowledge. To encourage students to think and self-regulate learning, students should be frequently exposed to opportunities to argue the acquired knowledge in generating explanations

Understanding of photosynthesis concepts related to students’ age

In Croatian schools, the complex photosynthesis concept is presented several times during primary and secondary school, each time with more detail. The problems in understanding photosynthesis processes are known from many previous studies and our own research ; thus we aimed to investigate how the students’ understanding of the basic photosynthesis concepts increases during the schooling period, and is it enhanced by gradual introduction of new contents. The present study was conducted on 269 students from 6 schools and 35 students preparing to be biology teachers. To test the students’ conceptual understanding, we implemented a question about the trends of O2 and CO2 gas concentrations during the night, which was expected to lead students to a correct explanation of photosynthesis, including the issues of the plants’ respiration and the absence of photosynthesis. Students of all age groups gave mainly incomplete explanations. The best result was achieved by the youngest participants in the age of 11, who have relied on the freshly acquired and well trained, but reproductive knowledge. Older students’ answers (aged 15, 17 and 22), which include more detail about the light-dependent and light-independent reactions, suggested that they developed misconceptions such as the belief that “oxygen is produced in Calvin cycle during the night” and that “CO2 converts to O2”. Student's explanations indicate the consistency of their understanding of the process, which does not change with gradual introduction of new contents as they are older. The observed misunderstanding could be linked to the cumulative introduction of the complex theoretical contents, but excluding research- based learning, as well as to inadequate time dedicated to establishing connections between students’ pre-conceptions and novel information. Our research results might be a strong argument supporting the upcoming change in the national curriculum

Teaching the topic Human nutrition through learning by research and basic principles of choice theory and quality school

Nepravilna prehrana je sve veći problem u modernim društvima, a javlja se već kod djece i adolescenata. Glavni cilj ovog rada je ukazati na metode i oblike poučavanja pomoću kojih se može osvijestiti važnost pravilne prehrane kod djece osnovnoškolskog uzrasta. Provedeno je učeničko istraživanje prehrane učenika petog i sedmog razreda osnovne škole, kako bi se utvrdio dnevni broj obroka i raznolikost prehrane učenika, a na osnovu rezultata istraživanja, učenike se - kroz prilagodbu nastavnih aktivnosti interesima učenika - vodilo u učenju o zdravim prehrambenim navikama. Rezultati učeničkog istraživanja pokazali su da učenici koji su sudjelovali u istraživanju konzumiraju najmanje tri obroka i barem jednu vrstu voća ili povrća dnevno, što povezujemo s prethodnim istraživanjima koja tumače da na prehrambene navike djece i mladih uvelike utječu različiti okolišni čimbenici, poput prehrambenih navika roditelja, tradicije i medija. Rezultati učeničkog istraživanja poslužili su kao osnova za daljnje poučavanje o temi pravilne prehrane čovjeka, odnosno za izgradnju predviđenih bioloških koncepata i učeničkih stavova te za razvijanje sposobnosti primjene usvojenih znanja o prehrani na primjerima iz svakodnevnog života. Kroz sve nastavne aktivnosti opisane u ovom radu, učenici su pokazali interes za temu pravilne prehrane i voljni su razviti zdravije prehrambene navike, a mi iznosimo mišljenje da bi se to moglo i postići primjenom osnovnih načela kvalitetne škole i teorije izbora u nastavi, koji se temelje na tome da učenici samostalno odabiru svoje buduće ponašanje i/ili korigiraju postojeće navike temeljem informacija koje samostalno prikupe i obrade. U jednom dijelu ovog istraživanja, nastavni sadržaj je prilagođen interesu učenika, što je rezultiralo velikom aktivnošću učenika, ukazujući na pozitivne učinke primjene načela kvalitetne škole i teorije izbora u nastavi biologije. Sugeriramo da bi sudjelovanje učenika u kreiranju nastave vjerojatno pomoglo u stvaranju kvalitetnijeg odnosa između učenika i nastavnika i pozitivnijeg okruženja za učenje, što je također jedna od osnovnih postavki kvalitetne škole. Također, veća uključenost učenika u kreiranje nastave može poslužiti i kao podrška u izgradnji (pozitivnih) stavova učenika, odnosno kao poticaj na pozitivne promjene u ponašanju (izboru prehrambenih namirnica) učenika. Nadalje, temeljem rezultata ovog istraživanja, predlažemo da nastavnici detaljno bilježe učeničku aktivnost tijekom nastavnih sati, što bi im moglo pomoći u samoprocjeni vlastitog rada, kao i u procjeni učeničkog interesa za pojedine nastavne teme i oblike rada.Malnutrition is a growing problem in modern societies and is already occurring among children and adolescents. The main goal of this study was to point out the methods and forms of teaching that can be used to raise awareness of the importance of healthy nutrition among primary school students. Student research on the nutrition of fifth and seventh grade elementary school students was conducted to investigate the daily meals and the diversity of students’ nutrition. Based on the research results, by adapting teaching activities to students\u27 interests, students were guided in learning about healthy eating habits. The results of student research showed that students who participated in the study daily consumed at least three meals and at least one type of fruit or vegetable. We link these findings to previous research explaining that children\u27s and young people\u27s eating habits are greatly influenced by various environmental factors, such as parents\u27 eating habits, traditions and media. The results of the student research served as a basis for further teaching on the topic of healthy human nutrition, i.e. for building predicted biological concepts and student attitudes, and for developing the ability of applying the acquired knowledge about nutrition on everyday life examples. During the teaching activities, students expressed their interest in the topic of healthy nutrition and in developing healthier eating habits. We are of opinion that this could be achieved by applying the basic principles of quality school and theory of choice during teaching, which is based on students independently choosing their future behavior and/or on correcting their existing habits, based on information they independently collect and process. In one part of this research, the teaching content was adjusted to the student interests, which resulted in increased student activity, pointing to the positive effects of applying the principles of quality school and choice theory in teaching biology. We suggest that student participation in creating lessons would probably help to create a better relationship between students and teachers and a more positive learning environment, which is also one of the quality school basic settings. In addition, greater student involvement in creating lessons can support building (positive) student attitudes or encourage positive changes in behavior (food choices) of students. Furthermore, based on the results of this research, we suggest that teachers record student activity in detail during classes. It could help them in self-assessment of their work, as well as in assessing student interest in certain teaching topics and forms of work

The effect of active teaching in the primary school\u27s ecological content

Cilj istraživanja bio je utvrditi koliko aktivno uključivanje učenika u nastavu utječe na kvalitetu stečenih znanja, kao i na motivaciju te stav učenika prema aktivnoj nastavi. Istraživanje je provedeno na uzorku od 64 učenika u tri šesta odjeljenja u osnovnoj školi A.B. Šimića u Zagrebu. Učenici su podijeljeni u eksperimentalnu i kontrolnu skupinu. Eksperimentalna skupina je nastavnu jedinicu Listopadna šuma obradila uz aktivnu nastavu u grupnom, samostalnom i radu u parovima kroz zadatke i nastavu u prirodi. Kontrolna skupina poučavana je klasičnim frontalnim radom nastavnika. Od instrumenata za prikupljanje podataka korištene su tri pisane provjere znanja te anketa za učenike. Pisana provjera provedena je prije istraživanja i nakon svakog provedenog dijela aktivne nastave, a anketiranje učenika na kraju provedenog istraživanja. Rezultati pokazuju povećanu motivaciju, ali i uspješnost učenja u aktivnoj nastavi, a posebno u aktivnostima koje uključuju nastavu u prirodi. Učenici svaku aktivnu tehniku učenja koja im omogućuje slobodu istraživanja i rada izvan učionice doživljavaju pozitivno. Logaritamski oblik regresije bolje objašnjava postignuti uspjeh učenika, ali linearni model još uvijek pokazuje zadovoljavajuću pouzdanost te umanjuje značaj rijetkih pojedinačnih rezultata uspješnosti pa ga je bolje koristiti za prikaz ukupne slike uspješnosti u provjerama znanja. Rezultati istraživanja potvrđuju potrebu korištenja aktivne nastave uz naglasak na boravak učenika u prirodi i korištenje različitih oblika rada koji potičuThe aim of the research was to determine how active students\u27 involvement influences the quality of acquired knowledge, as well as students\u27 motivation and attitudes towards active teaching. The survey was conducted on a sample of 64 students in three sixth grade classes of elementary school. The students were divided into experimental and control group. The experimental group was learning about the topic of deciduous forest, taking active learning in the group, independent work and work in pairs through different tasks and in the field work. The control group got classical frontal lecturing. Three written tests, examining knowledge and a survey for students were used as data collection tools. Written examination was carried out prior to the research and after each sequence of active learning. The survey of students\u27 motivation and attitudes took part at the end of the research. The results show increased students\u27 motivation, as well as the success in learning, especially when the activities involved field work. Each active learning technique, that allowed students applying independent research steps and work outside of the classroom, was positively evaluated. The logarithmic form of regression better explains the learner\u27s achievement, but the linear model still shows satisfactory reliability and reduces the importance of a few individual performance results so it is better to use it to show overall image performance in knowledge testing. The research results confirm the need for using active learning, with an emphasis on field work in the nature, as well as various teaching methods that encourage student activity. In this way, students\u27 satisfaction, as well as their learning success, would be significantly increased

Veličinska struktura ličinki vodenih kukaca tijekom naseljavanja

Colonization of aquatic insect larvae was investigated in a second order woodland stream using trays filled with natural substrate. Patterns of colonization differed significantly between seasons in terms of number of taxa, density and biomass of aquatic insect assemblages. Larvae in the first (out of five) size class made up 35.5% of all colonizers during the spring, highest share of 54.1 % during the summer, 40.8% and 17.5% during the autumn and winter, respectively. Many peak values in density during spring and summer matched with single-species mass colonization of first or second size classes, explained by »distributional drift« of newly-hatched insects, or direct oviposition on substrate. Size structure of the community did not change with time of exposition, although it reflected life histories of the aquatic insects, which led to seasonal changes in colonization patterns.Naseljavanje ličinki vodenih kukaca praćeno je u šumskom potoku drugog reda upotrebom podloga s prirodnim supstratom. Kolonizacija se značajno razlikovala između godišnjih doba s obzirom na broj svojti, brojnost i biomasu zajednica vodenih kukaca. Ličinke prvog (od pet) veličinskog razreda imale su udio od 35,5% među svim kolonizatorima tijekom proljeća, najveći udio od 54,1% tijekom ljeta, 40,8% i 17,5% tijekom jeseni i zime. Mnoge vršne vrijednosti brojnosti tijekom proljeća i ljeta odgovarale su masovnom naseljavanju jedne svojte prvog ili drugog veličinskog razreda, što je objašnjeno »distribucijskim driftom« mladih ličinki, ili direktnim polaganjem jajašaca na podlogu. Veličinska struktura cijele zajednice nije se mijenjala s vremenom ekspozicije, već je odražavala svojstva životnih ciklusa vodenih kukaca što je dovelo do sezonskih promjena u obrascima naseljavanja