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The effect of foliar fertilization treatments on the basic chemical composition of must and base wine cv. Istrian Malvasia (Vitis vinifera L.)
No full text'Malvazija istarska' (Vitis vinifera L.) jedna je od najznačajnijih bijelih sorata u Hrvatskoj. Njezina kvaliteta prepoznata je kako u Hrvatskoj, tako i šire, stoga se domaći proizvođači sve češće odlučuju za ovu sortu. Razvojem tehnologije i sve većom potražnjom tržišta za pjenušavim vinima, raste i interes lokalnih proizvođača za proizvodnjom pjenušca od 'Malvazije istarske'. Mošt za proizvodnju baznoga vina za pjenušce po svom sastavu treba zadovoljavati svojstva kao što su niža pH vrijednost i koncentracija šećera, te viša ukupna kiselost s većim udjelom vinske kiseline, naspram jabučne. S obzirom na to da se 'Malvazija istarska' uzgaja pretežito u Istri, gdje je klima mediteranska, a najzastupljenije tlo crvenica, teško je zadovoljiti sva navedena svojstva potrebna za proizvodnju baznoga vina, posebice u suhim i vrućim godinama. Poznato je da sastav i dostupnost minerala iz tla ima značajan utjecaj na kemijski sastav mošta. Posebno je to važno za dostupnost kalija, za koji je dokazano da utječe na porast pH vrijednosti mošta i smanjuje koncentraciju ukupne kiselosti što ima nepovoljan utjecaj na kakvoću baznog vina. Također višak kalija često blokira usvajanje magnezija, te dolazi do njihovog nepovoljnog međuodnosa. Kako nedostatak vode tijekom vegetacije može usporiti i smanjiti dostupnost minerala, posebice magnezija bitnog za proces fotosinteze, a time i utjecati na kvalitetu baznoga vina, folijarna gnojidba jedan je od načina da se taj nedostata nadoknadi. Unatoč ovim važnim saznanjima mali broj autora se bavio istraživanjima utjecaja folijarne gnojidbe na sastav i kvalitetu baznoga vina u proizvodnji pjenušca. Stoga je cilj ovog istraživanja bio utvrditi utjecaj folijarne gnojidbe na količinu biogenih elemenata i suhu tvar u lišću vinove loze, te na svojstva mošta (ukupnu kiselost, organske kiseline, pH vrijednost, koncentraciju šećera) i baznoga vina (alkohol, ukupni suhi ekstrakt, pepeo, pH vrijednost, ukupnu kiselost, hlapljivu kiselost). Istraživanje je uključivalo četiri gnojidbena tretmana (T1, T2, T3 i T4) u tri repeticije. Pokus je bio postavljen po slučajnom bloknom rasporedu (RCBD) na sorti 'Malvazija istarska', podloga SO4, kroz dvije godine (2013. i 2014.). Tretmani su bili: T1 - NPK, T2 - NPK + Agromag (6 % MgO), T3 - NPK + Agromag + Fosforo (30 % P205) i T4 - NPK + Agromag + Fosforo + Bio Prot). Dobiveni rezultati ukazuju na postojanje značajnog utjecaja gnojidbenih tretmana na količinu kalija, kalcija, magnezija, željeza, cinka i bakra u lišću 2013., te kalija 2014. godine. Najveći utjecaj na smanjenje kalija u obje godine istraživanja imao je tretman T2 odnosno tretman magnezijem. Pozitivan utjecaj folijarnih tretmana na koncentraciju šećera, pH vrijednost i ukupnu kiselost mošta zabilježen je u 2013. godini, te na pH vrijednost i koncentraciju šećere u 2014. godini. Viši udio vinske kiseline i najniži udio jabučne kiseline imali su tretmani T3 i T4 u obje godine. Istraživanjem je utvrđena pozitivna korelacija između suhe tvari s pH vrijednosti i prinosom, te kalija i kalcija s ukupnom kiselosti u sušnoj 2013. godini. U vlažnoj 2014. godini utvrđena je pozitivna korelacija ukupne kiselosti i kalija, te negativna ukupne kiselosti i magnezija, što dodatno upućuje da je međuodnos kalija i magnezija za vinovu lozu bitniji od njihovih apsolutnih količina. Iako nije utvrđen značajan utjecaj tretmana na kemijski sastav baznoga vina, iz dobivenih rezultata vidljiv je trend opadanja pH vrijednosti i rasta ukupne kiselosti 2013. godine, te trend rasta ukupnog suhog ekstrakta u obje godine. Iz dobivenih rezultata vidljivo je da postoji povoljan utjecaj gnojidbenih tretmana na svojstva mošta i baznoga vina, a kako su se u istraživanju koristile minimalne doze preporučene od proizvođača za pojedina folijarna gnojiva, ostaje mogućnost daljnjih istraživanja. Dobiveni rezultati mogli bi biti znanstveni temelj pri dizajniranju folijarnih gnojidbenih tretmana u vinogradima sličnih agroekoloških karakteristika, gdje se grožđe ciljano koristi za proizvodnju pjenušavog vina.'Istrian Malvasia' (Vitis vinifera L.) is one of the most important white cultivars in Croatia. Its quality is recognized both in Croatia and throughout the world, which is the reason why domestic producers are increasingly opting for this cultivar. With the development of technology and an increase in the market demand for sparkling wines, there is also a growing interest of local producers in the production of sparkling wines from 'Istrian Malvasia'. In 2018., sparkling wine production accounts for an average of 7 % of global wine production and the volume of global exports accounted for 9 % of the total wine exported worldwide, representing 20 % of the total value of exported wine. That indicate sparkling wines are was increasingly produced in warmer and drier regions of the world, so it is difficult to achieve satisfactory parameters in the chemical composition of the base wine, which limits their production despite the adaptation of agricultural techniques and earlier harvest dates. The composition of must for the production of base wine for sparkling wine should satisfy components such as a lower pH value and sugar concentration, as well a higher content of total acidity with a higher proportion of tartaric acid, compared to malic acid. A high pH in the must is not desirable because it directly affects the wine by reducing the quality and stability of the color, negatively affecting the freshness and aging potential, and giving the wines an inharmonious taste. These negative effects are undesirable in the pro-duction of base wines for sparkling wine, because sparkling wines need freshness and a long aging potential. Preferably, base wines have a pH between 2,90 and 3,10. In base wine, a total acidity of 6,00 – 8,00 g/L is desirable, and this level is reduced by the precipitation of potassium bitartrates during must vinification. Since a high alcohol content in base wines is not desirable and an addi-tional 1,3 – 1,5 % vol. alcohol is formed during secondary fermentation, it is important that the sugar content in the must is not too high. The preferred alcohol content in the base wine is up to 11,5 %. vol. Given that 'Istrian Malvasia' is grown mainly in Istria, where the climate is Mediterranean, and the most common soil is red, it is difficult to satisfy all the mentioned components required for the production of base wine, especially during dry and hot years. It is known that the composition and availability of minerals from the soil have a significant influence on the chemical composition of the must. This is especially important for the availability of potassium, which has been proven to increase the pH value of the must and reduce the concentration of total acidity, which are unfavorable components for base wine. The idea of the possible positive effect of foliar fertilization with magnesium, phosphorus and amino acid-based biostimulants on the potassium decrease of leaves and, consequently, on the chemical composition of must arose from the knowledge of the strong antagonistic effect of potassium and magnesium. Potassium blocks the uptake and especially the translocation of magnesium in the plant much more than vice versa. Therefore, in soils with excess potassium or excessive application of potassium fertilizers, magnesium deficiency often occurs due to their antagonistic relationship and large K/Mg ratio. Foliar application of magnesium decreases the K/Mg ratio. Since the lack of water during growing season can slow down and reduce the availability of minerals, especially magnesium, which is essential for the photosynthesis process, and thus affect the quality of the base wine, foliar fertilization is one of the possibilities which can compensate for this lack. Also, foliar application of magnesium decreases the K/Mg ratio. Despite this important knowledge, a small number of authors have done research on the influence of foliar fertilization on the composition and quality of the base wine in the production of sparkling wines. Therefore, the aim of this research was to determine the influence of foliar treatments on the amount of plant nutrients and dry matter in the leaves, as well as on the properties of the must (total acidity, organic acids, pH value, sugar concentration) and base wine (alcohol, total dry extract, ash, pH
value, total acidity, volatile acidity). The research included four fertilization treatments (T1, T2, T3 and T4) in three repetitions. The experiment was set up according to a randomized block arrangement (RCBD) on the cultivar 'Istrian Malvasia', rootstock SO4, for the duration of two years (2013 and 2014). The treatments were as follows: T1 - NPK, T2 - NPK + Agromag (6 % MgO), T3 - NPK + Agromag + Fosforo (30 % P205) and T4 - NPK + Agromag + Fosforo + Bio Prot). The obtained results indicate that there is a significant influence of fertilization treatments on the amount of potassium, calcium, magnesium, iron, zinc and copper in the leaves in 2013, and potassium in 2014. Treatment T2, treatment with magnesium, had the greatest influence on the decrease of potassium in both years. A positive influence of foliar treatments on the sugar concentration, pH value and total acidity of must was recorded in 2013, and on pH value and sugars concentration in 2014. Treatments T3 and T4 had a highest proportion of tartaric acid and the lowest proportion of malic acid in both years. A positive correlation between dry matter with pH value and yield was established by this research, and potassium and calcium with total acidity in the dry year of 2013. In the wet year of 2014, a positive correlation of total acidity and potassium, and a negative correlation of total acidity and magnesium was determined, which additionally indicates that the relationship between potassium and magnesium is more important for grapevine than their absolute amounts. Although no significant influence of the treatment on the chemical composition of the base wine was determined, the obtained results show a trend of a decrease in pH values and an increase of total acidity in 2013, as well as a trend of growth of total dry extract in both years. From the obtained results, it is evident that there is a certain favorable influence of fertilization treatments on the components of the must and the base wine, and as minimum dosages recommended by the manufacturer for individual foliar fertilizers were used in the research, this leaves room for additional research. This approach to the application of foliar fertiliza-tion aimed at correcting the chemical composition of the must could reduce the need for corrective measures in the must and wine during the production process. The obtained results could be a scientific foundation for designing foliar fertilization treatments in vineyards with similar agroecological characteristics, where grapes are targeted for the production of sparkling wines
Composition of the ichthyofauna of the Lika river basin
No full textIhtiofauna Like se u prošlosti sastojala od gotovo isključivo endemskih vrsta riba. Od kraja 19. stoljeda čovjek je unio i translocirao velik broj stranih vrsta riba u cijelu ličku regiju. Cilj ovog rada bio je utvrditi sastav ihtiofaune sliva rijeke Like, usporediti zajednice riba različitih tekudica te utvrditi stupanj bioraznolikosti, prisutnost endemskih vrsta i opde stanje zajednica. Kroz godinu dana na ukupno pet lokacija uzorkovanje ribe obavljano je elektroribolovom pri čemu je obuhvaden transekt od minimalno 50 metara vodotoka. Pomodu statističkih metoda analize podataka (ANOSIM, SIMPER, Shannon-Wiener indeks, cluster analiza, krivulja dominacije i ABC dijagram) došlo se do zaključka kako u velikoj vedini sliva prevladavaju unesene vrste poput klena i sunčanice, dok je endemska vrsta jadovska gaovica potisnuta u gornji dio toka Jadove.In the past, the ichthyofauna of Lika consisted almost exclusively of endemic fish species. Since the end of the 19th century man has introduced and translocated a large number of foreign fish species to the entire Lika region. The goal was to determine the composition of the ichthyofauna of the Lika river basin, to compare the fish communities of different streams and to determine the degree of biodiversity, the presence of endemic species and the general condition of fish communities. Over the course of a year, at a total of five locations, fish were sampled by electrofishing, covering a transect of at least 50 meters of the watercourse. By means of statistic data analysis methods (ANOSIM, SIMPER, Shannon-Wiener index, cluster analysis, dominance curve and ABC diagram), it was concluded that introduced species such as chub and pumpkinseed sunfish predominate in the vast majority of the basin, while the endemic species Jadova minnow is repressed to the upper part of Jadova river
Izgledi za razvoj agroturizma u Sisačko-moslavačkoj županiji
No full textU ovom diplomskom radu govorit će se o agroturizmu i njegovim mogućnostima za razvoj u Sisačko-moslavačkoj županiji nakon posljedica pandemije Covid 19 i potresa. Ruralni turizam, a posebno agroturizam postaje sve atraktivnija poslovna aktivnost temeljena na motivima za novim doživljajima: upoznavanjem kulture drugačije od vlastite, povijesti nekog kraja, načina života lokalnog stanovništva u zajednici koja nije poznata, a posebno načina života poljoprivrednika i ponude hrane proizvedene na takvim gospodarstvima. Istraživanjem su prikupljeni stavovi i mišljenja članova agroturističkih gospodarstava, potencijalnih potrošača te vanjskih dionika. Anketnim istraživanjem suradnje ruralnog turizma s drugim poslovnim subjektima i lokalnim stanovništvom. Naglasak istraživanja je u ocjenjivanju utjecaja Covida 19 i potresa na poslovanje i potražnju za uslugama ruralnog turizma u Sisačko-moslavačkoj županiji. Analizom dobivenih podataka identificirane su mogućnosti za razvoj agroturizma u Sisačko-moslavačkoj županiji.This thesis will talk about agrotourism and its possibilities for development in Sisak-Moslavina County after the consequences of the Covid 19 pandemic and the earthquake. Rural tourism, especially agritourism, is becoming an increasingly attractive business activity based on motives for new experiences: getting to know a culture different from own, the history of an area, the way of life of the local population in a community that is not known, especially the way of life of farmers and the supply of food produced on such economies. The research collected the views and opinions of the members agritourism farms, potential consumers and external stakeholders. By survey by researching the cooperation of rural tourism with other business entities and local population. The emphasis of the research is on assessing the impact of Covid 19 and the earthquake on business and demand for rural tourism services in Sisak-Moslavina County. The analysis of the obtained data identified opportunities for the development of agrotourism in Sisak-Moslavina Count
Tenders as a method of designing public space-exampels from three european cities
No full textIskustva gradova Europske unije u provođenju javnih natječaja mogu poslužiti kao korisni primjeri dobre prakse, koji su, uz odgovarajuće prilagodbe kontekstu, primjenjivi na Zagreb. U prvom dijelu rada, istražena je i uspoređena natječajna regulativa gradova Beča, Ljubljane i Zagreba kroz pregled relevantne literature. Drugi dio rada fokusira se na analizu prvonagrađenih radova natječaja za uređenje javnih gradskih površina. U trećem dijelu rada, provedena je sinteza i vrednovanje natječajnih radova koristeći metodu K. Lyncha. Provedena je i online anketa kojom se ispitala percepcija stanovnika o utjecaju natječajnih realizacija na javni prostor grada Zagreba. Realizirani urbanistički projekti koji su nastali putem javnih natječaja svjedoče o pozitivnom trendu u suvremenom oblikovanju prostora i poboljšanju kvalitete života u gradu. Temeljem provedenog istraživanja formiran je prijedlog mogućih smjernica za unapređenje procesa natječaja u oblikovanju javnog prostora grada Zagreba.Experiences of European Union cities in conducting public tender can serve as valuable examples of good practice, which, with appropriate adaptations to the context, can be applied to Zagreb. The first part of the study explores and compares the tender regulations of Vienna, Ljubljana, and Zagreb through a review of relevant literature. The second part of the study focuses on the analysis of award-winning projects from tenders for the design of public urban spaces. In the third part of the study, a synthesis and evaluation of competition projects are carried out using K. Lynch's method. An online survey was also conducted to examine the residents' perception of the impact of tender realizations on the public space of the city of Zagreb. Urban planning projects that have been made through public tender bear witness to a positive trend in contemporary spatial design and contribute to enhancing the quality of life in the city. Based on the conducted research, a proposal for possible guidelines to improve the competition process in designing Zagreb's public spaces has been formulated
Silvopastoral systems with fruit trees and livestock
No full textSilvopastoralni sustavi su oblik poljoprivredne proizvodnje gdje se kombiniraju drveće, krmno bilje i životinje na istom mjestu. Na temelju literature, donosi se pregled dosadašnjih saznanja o silvopastoralnim sustavima s voćnim vrstama i domaćim životinjama. Tradicionalni silvopastoralni sustavi često se napuštaju, no postaju češći njihovi moderni oblici. Istraživanja sugeriraju da silvopastoralni sustavi pridonose očuvanju bioraznolikosti i kvaliteti vode i tla, smanjuju gubitak hranjivih tvari i eroziju tla kao i rizik od požara te povećavaju sekvestraciju ugljika. Uz to, pridonose očuvanju tradicionalne kulturne baštine te dobrobiti i produktivnosti domaćih životinja. Nedostatci uključuju visoko početno ulaganje, mogućnost oštećenja drveća od strane životinja te poteškoće s mehanizacijom. Donose se smjernice za podizanje i uzdržavanje silvopastoralnog sustava. Potrebno je provesti dodatna istraživanja o dugoročnoj održivosti ovakvih sustava te educirati o njihovom potencijalu.Silvopastoral systems are a form of agriculture where trees, forage plants and animals are combined in the same place. Based on the literature, an overview of current knowledge on silvopastoral systems with fruit trees and livestock is presented. Traditional silvopastoral systems are often abandoned, but their modern forms are becoming more common. Research suggests that silvopastoralism contributes to the preservation of biodiversity and water and soil quality, reduce nutrient loss, soil erosion and fire risk, and increase carbon sequestration. They also help preserve traditional cultural heritage and the well-being and productivity of livestock. Disadvantages include high initial investment, possible damage to trees by cattle, and difficulties with mechanization. Guidelines for raising and maintaining a silvopastoral system are presented. It is necessary to conduct additional research on the long-term sustainability of such systems as well as to educate about their potential
Content of potassium and iron in tomato products
No full textRajčica (Lycopersicon esculentum Mill.) je jednogodišnja povrtna kultura čiji se plodovi mogu konzumirati u svježem stanju ili prerađeni. U plodovima rajčice kalij je jedan od najzastupljenijih minerala, no sadrži i značajnu količinu željeza. Cilj ovog diplomskog rada bio je utvrditi količinu kalija i željeza u uzorcima proizvoda od rajčice iz različitih serija proizvodnje. Uzorkovanje je provedeno na šest proizvoda od rajčice (kečap, dvostruki koncentrat, pelati, pasirana rajčica te sjeckana rajčica iz konvencionalnog i ekološkog uzgoja). Nakon sušenja na 105 °C uzorci su razgrađeni s HNO3 i HClO4 u mikrovalnoj peći te je kalij određen na plamenfotometru, a željezo na atomskom apsorpcijskom spektrometru. Statistička obrada podataka pratila je model analize varijance (ANOVA). Količina kalija u suhoj tvari kretala se od 1,36 do 5,37 % K u ST, a u svježoj tvari od 185,19 do 1224,46 mg K/100 g svježe tvari. Količina željeza u suhoj tvari kretala se od 24,30 do 155,07 mg Fe/100 g ST, a u svježoj tvari od 0,42 do 1,23 mg Fe/100 g svježe tvari. Najveća količina kalija na bazi suhe i u svježoj tvari utvrđena je u koncentratu rajčice. Najviše željeza na bazi suhe tvari utvrđeno je u sjeckanoj rajčici, dok je najveća količina željeza u svježoj tvari utvrđena u koncentratu rajčice.Tomato (Lycopersicon esculentum Mill.) is an annual vegetable crop whose fruits can be consumed fresh or processed. Potassium is one of the most abundant minerals in tomato fruits, but they also contain a significant amount of iron. The aim of this thesis was to determine the amount of potassium and iron in samples of tomato products from different production batches. Sampling was carried out on six tomato products (ketchup, double concentrate, canned tomatoes, pureed tomatoes and chopped tomatoes from conventional and organic farming). After sample preparation, drying at 105 °C, homogenization and digestion in a microwave oven using HNO3 and HClO4, potassium was determined by flame photometry while iron was determined by AAS (Atomic Absorption Spectroscopy). Statistical data analysis was performed using Analysis of variance method (ANOVA). The determined content of potassium in dry matter ranged from 1.36 to 5.37 % K DW. Potassium levels in fresh matter ranged from 185.19 to 1224, 46 mg K/100 g fresh weight. The determined content of iron in dry matter ranged from 24.30 to 155.07 mg Fe/kg DW. Iron levels in fresh matter ranged from 0.42 to 1.23 mg Fe/100 g fresh weight. The highest amount of potassium in dry and fresh matter was determined in tomato concentrate. The highest amount of iron based on dry matter was determined in chopped tomatoes, while the highest amount of iron in fresh matter was determined in tomato concentrate
Brown marmorated stink bug (Halyomorpha halys Stål, 1855) in apple orchards in Zagreb county
No full textSmeđa mramorasta stjenica invazivna je vrsta azijskog podrijetla utvrđena u Hrvatskoj
2017. godine. Polifagni je štetnik koji napada više od 200 kultura te uzrokuje
ekonomske štete u uzgoju. Cilj rada bio je utvrditi dinamiku ulova i brojnost štetnika u
tri voćnjaka jabuke (Mičevec, Petrovina Turopoljska i Staro Čiče) na području
Zagrebačke županije. Populacija štetnika praćena je tijekom 2022. pomoću
Pherocon® BMSB kompleta. Ulov štetnika započeo je voćnjaku Mičevec 7. lipnja 2022.
godine a trajao je do 9. studenog 2022. godine kada je u istom voćnjaku ulovljena
zadnja jedinka štetnika. Najveća brojnost stjenice ustanovljena je u voćnjaku Staro
Čiče (ukupno ulovljeno 25 jedinki štetnika). U drugim voćnjacima zabilježena je
značajnije niža brojnost štetnika (Petrovina Turopoljska – šest jedinki i Mičevec – pet
jedinki). Tjedni ulovi štetnika u voćnjaku Staro Čiče prelazili su kritičnu brojnost. S
obzirom na invazivni karakter štetnika, potrebno je i nadalje nadzirati njegovu aktivnost
u sva tri voćnjaka.The brown marmorated stink bug is an invasive species of Asian origin that was
discovered in Croatia in 2017. It is a polyphagous pest that attacks more than 200
crops and causes economic damage in cultivation. The aim of the work was to
determine the catch dynamics and abundance of the pest in three apple orchards
(Mičevec, Petrovina Turopoljska and Staro Čiče) in the region of Zagreb County. The
pest population was monitored in 2022 using the Pherocon® BMSB kit. The first
individuals of the pest were caught in Mičevec orchard on June 7, 2022, and continued
until November 9, 2022, when the last pest was caught in the same orchard. The
highest number of stink bugs was found in the Staro Čiče orchard (a total of 25
individuals of the pest were caught). In the other orchards (Petrovina Turopoljska – six
individuals and Mičevec – five individuals) a significantly lower number of pests was
found. In the Staro Čiče orchard, the weekly catch of pests exceeded a critical number.
Considering the invasive nature of the pest, it is necessary to continue monitoring its
activity in all three orchards
Production technology of pistachio seedlings
No full textPistacija pripada rodu Pistacia koji ima 11 vrsta iz obitelji Anacardiacea. Većina pistacija vrsta poput: P. terebinthus, P. atlantica, P. khinjuk, P. palaestine, P. mutica pokazala su se kao dobar izbor za podlogu, dok Pistacia vera ima i gospodarski značaj za uzgoj plodova. Posljednjih desetljeća podižu se nove plantaže i uzgajivači pistacija svjesni su važnosti odabira podloge i sorte. Proizvodnja sadnica pistacija ne zadovoljava postojeću potražnju zbog teškoća cijepljenja na određene podloge. Uspjeh cijepljenja kod pistacija ovisi o brojnim čimbenicima: temperaturi, vlažnosti, aktivnosti podloge itd. Cilj rada je utvrditi prikladnost metoda razmnožavanja pistacija u svrhu dobivanja kvalitetnog sadnog materijala i potrebne agrotehničke mjere koje su ključni čimbenici proizvodnje.Pistachios belong to the genus Pistacia, which comprises 11 species of the family Anacardiacea. Most of the pistachio species such as: P. terebinthus, P. atlantica, P. khinjuk, P. palaestine, P. mutica have proved to be good choices for substrate, while Pistacia vera is also of economic importance for fruit growing. New plantations have been established in the last decades and pistachio growers are aware of the importance of the choice of substrate and variety. The production of pistachio seedlings does not meet the current demand, as grafting onto certain substrates is difficult. The success of pistachio grafting depends on many factors: Temperature, humidity, activity of the substrate, etc. The aim of the work is to determine the suitability of pistachio propagation methods for obtaining quality planting material and the agrotechnical measures required, which are crucial for production
Overview of research on the genus of sea horses (Hippocampus)
No full textMorski konjići su posebna morska vrsta koja se izdvaja svojim jedinstvenim izgledom i ponašanjem. Pripadaju porodici Syngnathidae, koja također uključuje morske konjiće, morske zmije i šiljogubce. Morski konjići su vrsta koja je ugrožena i suočava se s raznim prijetnjama. Njihova ugroženost proizlazi iz kombinacije faktora, uključujući pretjerano iskorištavanje, uništavanje staništa kao što su koraljni grebeni i morske trave, onečišćenje voda i klimatske promjene te pretjerani izlov koji može imati ozbiljne posljedice na njihovu sposobnost razmnožavanja i dugoročni opstanak vrsta. Trgovina morskim konjićima u akvarističkoj industriji je praksa koja ima svoje kontroverze i rizike. Iako mnogi akvaristi uživaju u promatranju morskih konjića u svojim akvarijima, važno je biti svjestan utjecaja ove trgovine na populacije morskih konjića u prirodi. Medicina bazirana na morskim konjićima je jedan od faktora koji pridonosi ugroženosti ove vrste, koja vjeruje da imaju ljekovita svojstva i koriste se za liječenje različitih bolesti. Molekularna istraživanja morskih konjića pružaju važne uvide u njihovu genetiku, evoluciju, fiziologiju, reprodukciju i druge aspekte njihovog života. Provode se kroz razne molekularne tehnike i metode analize genoma i genetske varijabilnosti. Unaprjeđenje molekularnog istraživanja za morske konjiće može biti od ključne važnosti za bolje razumijevanje ove ugrožene vrste. Kako bi se zaštitili morski konjići, oni su uvršteni na IUCN-ovu Crvenu listu ugroženih vrsta, što ukazuje na njihovu ozbiljnu ugroženost.Seahorses are a special marine species that stands out for its unique appearance and behavior. They belong to the Syngnathidae family, which also includes seahorses, sea snakes and stingrays. Seahorses are an endangered species and face various threats. Their threat stems from a combination of factors, including overexploitation, destruction of habitats such as coral reefs and seagrasses, water pollution and climate change, and overfishing, which can have serious consequences for their ability to reproduce and the long-term survival of the species. Trading seahorses in the aquarium industry is a practice that has its own controversies and risks. Although many aquarists enjoy viewing seahorses in their aquariums, it is important to be aware of the impact of this trade on seahorse populations in the wild. Medicine based on seahorses is one of the factors contributing to the endangerment of this species, which is believed to have medicinal properties and is used to treat various diseases. Molecular studies of seahorses provide important insights into their genetics, evolution, physiology, reproduction and other aspects of their lives. They are carried out through various molecular techniques and methods of genome analysis and genetic variability. Advances in molecular research for seahorses may be critical to better understanding this endangered species. In order to protect seahorses, they have been included in the IUCN Red List of Threatened Species, which indicates their serious threat
Anaerobic digestion of cheese whey before and after curd production
No full textSirutka je nusproizvod koji nastaje nakon proizvodnje sira. Zbog količine u kojoj nastaje, sirutka mljekarskoj industriji predstavlja veliko opterećenje. Pretpostavlja se da se gotovo 50 % svjetske količine ispušta u otpadne vode čime predstavlja opasnost za onečišćenje okoliša, a ujedno se gubi i vrijedan resurs. Kao jedan od načina njezine upotrebe je proces anaerobne digestije kojim bi se od nusproizvoda mogao proizvesti bioplin. Bioplin je zapaljivi plin u čijem sastavu se u najvećoj mjeri nalaze metan i ugljikov dioksid, a njegova važnost kao jeftinog i CO2 neutralnog izvora energije proizlazi iz mogućnosti njegove upotrebe u transportu i proizvodnji toplinske i električne energije. U ovom radu uspoređuje se prinos bioplina i metana iz dvanaest uzoraka sirutke dobivene prije i poslije proizvodnje skute pri čemu su dodane različite količine limunske kiseline. Također, prikazana je međuzavisnost pojedinog uzorka o parametrima kao što su udio suhe tvari, udio vlage, te udio makro i mikro elemenata koji utječu na kvalitetu sirovine, te ovisnost prinosa bioplina i kemijske potrošnje kisika. Dobiveni rezultati su pokazali kako veće količine limunske kiseline u uzorku daju manji prinos bioplina, te kako na prinos metana u bioplinu utječe kvaliteta sirutke. Također, prema podacima kemijske potrošnje kisika dobivenim u istraživanju, vrijednosti koje se nalaze u uzorcima sirutke bile su optimalne te su uzorci sa najvišom vrijednosti dali najveći prinos bioplina.Whey is a by-product of cheese production. Due to the amount in which it is produced, the whey of the dairy industry represents a large burden. It is assumed that almost 50 % of the world's volume is discharged into wastewater, which represents a danger for environmental pollution, and at the same time a valuable resource is lost. One of the ways of its use is the process of anaerobic digestion, which could produce biogas from the by-products. Biogas is a flammable gas whose composition contains methane and carbon dioxide to the greatest extent, and its importance as a cheap and CO2-neutral source of energy stems from the possibility of its use in transport and production of heat and electricity. This research compares the yield of biogas and methane from twelve samples of whey obtained before and after the production of cottage cheese, to which different amounts of citric acid were added. Also, the interdependence of individual samples on parameters such as dry matter content, moisture content, and macro and microelements that affect the quality of the raw material, as well as dependence of biogas yield and chemical oxygen demand. The obtained results showed that larger amounts of citric acid in the sample give a lower yield of biogas, and that the yield of methane in biogas is affected by the quality of the whey. Also, according to the chemical oxygen consumption data obtained in the research, the values found in the whey samples were optimal and the samples with the highest values gave the highest biogas yield