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Processing and use of by-products of animal origin
No full textPredviđeni porast svjetske populacije za gotovo 35% u sljedeća tri desetljeća, rezultirat će povećanom potražnjom za životinjskim bjelančevinama, a samim time povećat će se globalna proizvodnja mesa, procijenjena na 480 milijuna tona godišnje. Povećanje globalne proizvodnje mesa pridonosi i proizvodnji sve većih količina klaoničkog otpada, odnosno nusproizvoda životinjskog podrijetla. Jestivi nusproizvodi se na tržištu ističu zbog svoje ekonomičnosti i nutritivne vrijednosti. Iznutrice se najviše primjenjuju u proizvodnji hrane za ljude i kućne ljubimce, te u različite farmaceutske i medicinske svrhe. Nejestivi životinjski nusproizvodi također imaju široku primjenu u prehrambenim, medicinskim i farmaceutskim industrijama. Boljim iskorištavanjem životinjskih nusproizvoda i njihovih prerađevina smanjuje se klaonički otpad i smanjuje se zagađivanje okoliša. Svakodnevna primjena životinjskih nusproizvoda i njihovih prerađevina u različite svrhe, pridonose održivosti suvremene proizvodnje mesa.The projected increase in the world's population by almost 35 % in the next three decades will result in an increased demand for animal protein, and thus increase global meat production, estimated at 480 million tons per year. The increase in global meat production also contributes to the production of increasing quantities of slaughterhouse waste, i.e. animal by-products. Edible by-products stand out in the market for their economy and nutritional value. Offal is mostly used in the production of food for humans and pets, and for various pharmaceutical and medical purposes. Inedible animal by-products are also widely used in the food, medical, and pharmaceutical industries. Better use of animal by-products and their derivatives reduces slaughterhouse waste and reduces environmental pollution. The daily use of animal by-products and their derivatives for various purposes contributes to the sustainability of modern meat production
Application of EU Geographical Indications for the Protection of Smoked Dry-Cured Ham—Impact on Quality Parameters
No full textThis study compares Dalmatinski pršut, an EU Protected Geographical Indication (PGI)-labelled smoked dry-cured ham from the Dalmatia region in Croatia, with non-PGI hams from the same area, focusing on the impact of PGI certification on the product quality. The investigation is prompted by the increasing presence of dry-cured hams lacking the PGI label on the market, aspiring to compete with esteemed high-value PGI products. Samples of 28 smoked dry-cured hams (12 PGI and 16 non-PGI) were analysed for chemical properties, fatty acid composition, volatile compounds, PAH content and sensory characteristics. The results showed that PGI and non-PGI hams differ in their chemical and physical properties, with non-PGI hams having a lower water content and a higher salt content, which was also confirmed by the saltier taste in the sensory evaluation. PGI hams had a lower b* colour value, and, while the differences in texture were minimal, non-PGI hams had slightly more monounsaturated fatty acids. The aroma analysis revealed that PGI hams contained more aldehydes and alcohols, while non-PGI hams had a higher content of phenolic compounds and aromatic hydrocarbons, probably due to differences in smoking practices. PAH levels, however, were within the EU limits, indicating controlled smoking of both type of hams. Overall, these results show that the quality of smoked dry-cured ham can be distinguished by the PGI designation. The study illustrates how the traditional production methods prescribed by the PGI production protocols shape the sensory and chemical profiles of Dalmatinski pršut, with the PGI certification playing a crucial role in maintaining product quality and certifying its typicality, to distinguish it from non-PGI products
Modeling the occurrence and intensity of water salinity in a hydromeliorated river delta by sensor monitoring
No full textKlimatske promjene, u prvom redu globalni porast prosječne razine mora uvjetuje intenzifikaciju intruzije morske vode u priobalne vodonosnike i površinske vodene tokove čime su posebno ugrožena nizinska područja riječnih delti. Za donošenje pravovremenih odluka i gospodarenje vodama i tlima u osjetljivim agroekosustavima riječnih delti nužna je uspostava sustava monitoringa. Klasični sustavi monitoringa koji podrazumijevaju uzorkovanje vode i laboratorijska ispitivanja sve češće se unaprjeđuju kontinuiranim in-situ sustavima primjenom različitih senzora. Za razliku od klasičnog monitoringa koji je važan za karakterizaciju kakvoće voda i detekciju dugoročnih trendova i sezonalnosti, in-situ kontinuirani monitoring visoke vremenske rezolucije omogućava kvantifikaciju ekstrema, kratkoročnih trendova i unutar dnevne varijabilnosti. Stoga su ciljevi istraživanja bili : i) usporediti pokazatelje zaslanjenosti izmjerene in-situ senzorima i klasičnim metodama monitoringa te ii) na temelju podataka dobivenih in-situ kontinuiranim monitoringom visoke vremenske frekvencije procijeniti utjecaj prirodnih i antropogenih čimbenika na zaslanjivanje površinskih i podzemnih voda riječne delte. Istraživanje je provedeno u dolini rijeke Neretve na dvije lokacije, Vidrice i Luke. Na obje lokacije instalirane su višeparametarske sonde za mjerenje električne vodljivosti ECw u površinskim i podzemnim vodama. Za monitoring vlažnosti i EC tla instalirani su FDR senzori do dubine 1 m na svakih 25 cm. Prikupljanje meteoroloških podataka omogućeno je automatskom agrometeorološkom stanicom instaliranom na lokaciji Vidrice. Svi podaci prikupljani su u visokoj vremenskoj rezoluciji (15 min-60 min ovisno o pokazatelju). Analizom višegodišnjeg seta podataka o kakvoći voda prikupljenih klasičnim monitoringom te jednogodišnjeg seta in-situ kontinuiranih mjerenja utvrđene su statistički značajne razlike u ECw površinskih i podzemnih voda na i između pojedinih lokacija. Utvrđene razlike posljedica su prirodnih i antropogenih čimbenika specifičnih za pojedinu lokaciju, a koji su detektirani in-situ kontinuiranim monitoringom. Usporedbom provedenih mjerenja nisu utvrđene statistički značajne razlike vrijednosti ECw dobivene klasičnim i in-situ monitoringom, a niske vrijednosti pogrešaka utvrđene su u površinskoj i podzemnoj vodi na lokaciji Luke te površinskoj vodi na lokaciji Vidrice. Prikupljeni podaci u satnoj i dnevnoj vremenskoj rezoluciji korišteni su za razvoj prognostičkih modela strojnog učenja i vremenskih serija. Korištenjem satnih ulaznih podataka bolje performanse pokazao je model XGB u odnosu na model MLR. Pouzdane tjedne prognoze s niskim vrijednostima pogrešaka MAE i RMSE postignute su u površinskoj vodi na lokaciji Vidrice, dok su pouzdane prognoze do mjesec dana unaprijed postignute u površinskoj vodi na lokaciji Luke i podzemnim vodama na lokacijama Vidrice i Luke. Primjenom dnevnih ulaznih podataka najbolje prognostičke performanse pokazao je ARIMA model, a najmanje pogreške utvrđene kod tjedne prognoze. Razvijeni i testirani predikcijski modeli satnih i dnevnih vrijednosti ECw mogu se koristiti za pouzdano kratkoročno predviđanje stupnja zaslanjenosti površinskih i podzemnih voda na odabranim lokacijama u hidromelioriranoj riječnoj delti. Rezultati provedenog istraživanja mogu poslužiti kao smjernice u planiranju načina gospodarenja vodama i tlima u ugroženim agroekosustavima kao što su riječne delte koje su pod izravnim i neprestanim pritiskom klimatskih promjena, u prvom redu podizanja razine mora i njegove intenzivnije intruzije u priobalna područja.One of the most important consequences of climate change, which threatens both surface and groundwater resources in coastal areas, is sea level rise. Although global sea levels have been rising throughout the 20th century, these processes have intensified towards the end of the century. According to data from the 2013 IPCC report, the mean value of global sea level rise was 1.7 mm per year in the period from 1901 to 2010, while it rose to 3.2 mm per year in the period from 1993 to 2010. Despite the global nature of the problem of sea level rise, the Mediterranean region, including the Adriatic, is one of the hotspots and most vulnerable areas. Sea level rise can intensify the natural processes of seawater intrusion (SWI) into coastal aquifers and surface waters, which can be exacerbated by anthropogenic activities such as the regulation of watercourses, excessive groundwater abstraction, etc. These processes particularly endanger lowland coastal areas such as estuaries and deltaic plains, which play a crucial socio-economic role in addition to their wealth of natural resources and biodiversity. SWI and changes in salinity within river deltas are the result of interactions between morphology and topography, tidal regimes and the inflow of freshwater from the catchment area. In the long term, SWI can have serious consequences in terms of degrading the quality of surface and groundwater resources. Consequently, the salinization of water resources can lead to soil salinization. Worldwide, more than 900 Mha of soil are classified as salt affected. In the short term, soil salinization can lead to reduced crop yields, while the long-term consequences are more severe, including a reduction in soil fertility and productivity, which could ultimately lead to permanent loss through desertification. In order to control and evaluate changes in vulnerable areas such as river deltas, environmental monitoring systems should be introduced, particularly to monitor soil and water quality. Many countries have developed and implemented water quality monitoring systems, most of which are regulated by law. Although technological advances have led to the development of means for automated and continuous water quality monitoring, most water quality monitoring systems are still carried out in the traditional way, usually with monthly sampling and laboratory analyses. While sampling-based monitoring is useful for the general characterization of water quality and the detection of long-term trends and seasonal variations, high-frequency in-situ sensor monitoring enables quantification of extreme events, short-term trends and sub-day variations in water quality parameters. Although weekly or monthly sampling may be sufficient for some parameters, such as pH, continuous data for parameters such as nutrients and ECw provide better opportunities for understanding hydrochemical processes in various water bodies. Continuous high-frequency sensor monitoring enables the collection of large amounts of data (big data) that can be used for advanced statistical modeling and the development of time series and machine learning models for long and short-term predictions of dynamic parameters such as ECw. Based on the above, two research hypotheses were tested: (I) surface and groundwater salinity indicators can be measured as accurately with in-situ sensors as with traditional monitoring methods; (II) surface and groundwater salinity will change over time due to natural and anthropogenic influences. The objectives of the research were (I) to compare salinity indicators measured with in-situ sensors and traditional monitoring methods; (II) to assess the impact of anthropogenic and natural factors on salinization of surface and groundwater over time using data obtained from in-situ measurements.
The research was carried out in the Neretva River delta on the east coast of the Adriatic Sea in Croatia. Within the delta, locations Vidrice (42°59'13'' S, 17°31'39'' I) and Luke (43°1'37'' S, 17°33'39'' I) were selected, which are characterized by a different spatial position and distance from the main watercourses, different soil properties and different land use and agricultural management practices. At both locations multiparameter probes measuring water temperature, depth, pH, ECw and ORP were installed in drainage canals for monitoring surface water and shallow piezometers (4 m deep) for monitoring groundwater quality. In the immediate proximity of the piezometers, FDR soil sensors were installed at both locations to measure temperature, moisture and ECb. In addition, sensors for soil water potential were installed at depths of 25 cm and 50 cm. Meteorological data was recorded using the automatic station installed at the Vidrice. Data loggers and modems were used to record and transmit real-time data in high temporal resolution. The collected in-situ data on water salinity were evaluated against the data from traditional monthly monitoring at the same locations. Descriptive statistics and ANOVA were performed for both long-term monthly monitoring (2010-2022) and continuous in-situ monitoring (2021-2022). High temporal frequency data collected through the established in-situ monitoring, in addition to water level data at the main watercourses, were used for the development of time series (ARIMA) and two machine learning models (MLR and XGB). The developed models were used to predict ECw seven, 14 and 30 days ahead and the predictions were evaluated using MAE and RMSE.
The results of the long-term traditional monthly monitoring showed that the average ECw of surface water at location Vidrice was 2.4 dS m-1, while a higher average ECw value (8.9 dS m-1) was measured in the groundwater, both with high variability. At location Luke, a higher salinity was found in the surface water (8.3 dS m-1) than in the groundwater (2.9 dS m-1). Analysis of the major ions showed that in both water bodies and at both locations the dominant cation was Na+ and the dominant anion was Cl-, with the exception of the groundwater at location Luke location the dominant anion was SO42-. The correlation analysis showed a positive, strongly significant correlation between ECw and Na+ and Cl- at both locations and for both water bodies. The ANOVA and the Tukey HSD post-hoc test showed that ECw differed significantly between the same water bodies at different sites as well as between different water bodies at each site. When analyzing the results of continuous in-situ water monitoring, no differences were determined between hourly and daily temporal frequency for any of the analyzed parameters at both locations in surface and groundwater. As with the traditional methods, higher average values of ECw were found in groundwater (12 dS m-1) compared to surface water (2.1 dS m-1) in the continuous in-situ monitoring at location Vidrice. In-situ continuous data showed clear differences in dynamics of ECw between surface water and groundwater. Intense precipitation events during non-growing periods resulted in highly dynamic changes in ECw in surface water, with hourly values ranging from 0.17 to 11 dS m-1. At the same time, each precipitation event in the groundwater led to a rapid decrease in ECw values. The less dynamic and slower changes in groundwater salinity compared to surface water are the result of the interaction of several parameters, such as pedological characteristics, aquifer recharge, distance to major watercourses and possible anthropogenic influences, such as the operation of pumping stations. At location Luke, a higher average ECw value was determined in the surface water (7.0 dS m-1) compared to the groundwater (3.7 dS m-1). The hourly time series of the ECw value in the surface water, where more dynamic changes were observed, show that precipitation had no direct influence on the ECw dynamics. The sudden and pronounced changes in the hourly data indicate that the salinity in the surface waters is predominantly subject to anthropogenic influences, namely the pumping regime. Similar to location Vidrice, the changes in ECw in the groundwater were less dynamic and slower. The ANOVA
revealed significant differences in ECw between surface water and groundwater at both locations and between the two study locations. The results indicate that the salinization of surface and groundwater at the selected locations are influenced by various natural and anthropogenic factors. The salinization of surface and groundwater at location Vidrice is mainly the result of the direct SWI into the coastal aquifer through the karstic coast in the southwest in combination with the permanent regulation of the water level (drainage canals, sluices, pumping stations, etc.). The changes in salinity of surface and groundwater at location Luke are primarily influenced by the stratified flow of the Neretva River and the SWI through the main riverbed. Evaluation of the in-situ measurements against the results of traditional monitoring showed a high correlation (0.97) and R2 value (0.94) for the surface water at location Vidrice with very low MAE (0.13 dS m-1) and RMSE (0.18 dS m-1) values, indicating a high degree of accuracy. At the same location, more significant deviations were observed for groundwater, with an R2 value of 0.28, together with errors of 2 dS m-1 for MAE and 3.16 dS m-1 for RMSE. The low accuracy and more significant differences in groundwater could be due to the different sampling depths in non-growing period when heavy rainfall occurred, leading to rapid changes in the water table. At location Luke, high correlation and R2 values were found between the two monitoring approaches for both surface water and groundwater. Lower error values were observed in the groundwater (MAE=0.32 dS m-1 and RMSE=0.39 dS m-1) compared to surface water (MAE=0.48 dS m-1 and RMSE=0.71 dS m-1). The changes in soil moisture and ECb up to 75 cm were influenced by precipitation and the associated rise in groundwater water table during the non-growing period as well as by precipitation and irrigation during the growing season at location Vidrice. The almost constant moisture in the deepest layer was mainly influenced by groundwater, which was within 1.5 m below the soil surface during most of the study period. A similar pattern was observed for ECb, where precipitation and the rise in groundwater water table during the non-growing period influenced the changes in ECb throughout the profile. The highest values were found in the deepest layer, which was also influenced by saline groundwater. During the growing season, when the water table was below 1.5 m and the orchard was irrigated, changes in ECb were observed in the top 75 cm of the soil profile. At location Luke, a higher average soil moisture was found in the upper half of the soil profile (0-50 cm), with the highest average value found in the 25-50 cm layer. The analysis of the changes in the dynamics of soil moisture and ECb showed that during the growing season in 2021 and 2022, irrigation measures had the greatest influence on the changes up to a depth of 75 cm. During the non-growing period, the changes in soil moisture and ECb were influenced by precipitation and the associated rise in the groundwater table. The data collected at hourly and daily temporal resolution was used to develop machine learning and time series for predicting ECw. The XGB model performed better than the MLR model on hourly input data. Satisfactory results with low MAE and RMSE were obtained for the prediction of seven days ahead in surface water at location Vidrice and up to 30 days ahead in surface and groundwater at location Luke as well as in groundwater at location Vidrice. Using daily input data, the ARIMA model showed the best performance, with the lowest errors observed for the seven-day-ahead prediction. The developed and tested models can be used for reliable short-term prediction of ECw in surface and groundwater at selected locations in the hydro-meliorated river delta. The results of this research can guide the planning of future water and soil management practices in vulnerable agro-ecosystems such as river deltas that are under pressure from climate change, especially sea level rise, and increased SWI
Soil respiration dynamics in arable crops vegetation
No full textTijekom posljednjih nekoliko desetljeća, rastom globalne populacije raste i životni standard, a time i kumulativna razina emisije stakleničkih plinova. Upravo sve veće emisije stakleničkih plinova uzrokovane ljudskim aktivnostima, kao posljedica njihovog ispuštanja iz nekih od sektora, kao što su energetika, industrija i poljoprivreda, dovode do njihove akumulacije u atmosferi, što rezultira promjenama u atmosferi, kopnu i oceanima. Od mnogih stakleničkih plinova, ugljikov dioksid (CO2) predstavlja jedan od najvažnijih spojeva koji utječu na procese globalnog zagrijavanja te se smatra pokretačem globalnih klimatskih promjena. Kruženje ugljika u prirodi nezamislivo je bez tla kao bitne sastavnice okoliša, što potvrđuje da su tlo i klima oduvijek bili usko povezani. Stoga je bitno naglasiti kako je jedan od glavnih čimbenika u borbi protiv klimatskih promjena upravo tlo. S dvostruko većim sadržajem ugljika od atmosfere, ono značajno pridonosi bilanci ugljika. Upravo iz tog razloga, važno je pravilno upravljati tlom, usporavajući tempo klimatskih promjena kroz prakse poput smanjene obrade, pravilne gnojidbe te optimiziranog plodoreda u poljoprivredi. Cilj ove disertacije bio je terenskim mjerenjima utvrditi ovisnost C-CO2 emisije tla o tipu gnojidbe (I.-kontrola; II.- N250 + P + K + 40 t/ha organskog krutog stajskog miješanog gnoja; III.-N300 + P + K; IV.-crni ugar - obrada bez sjetve) u tri vegetacijske godine (2016., 2017. i 2018.) za tri vrste usjeva (ozima pšenica, kukuruz i soja), te provesti bilanciranje odnosno utvrditi prilive i odlive ugljika iz tla na svim istraživanim tretmanima i utvrditi ovisnost o emisiji C-CO2 iz tla. U vegetaciji ozime pšenice, prosječna godišnja emisija C-CO2 iz tla iznosila je 17,96 kg ha-1 dan-1, u vegetaciji kukuruza 11,19 kg ha-1 dan-1, te u vegetaciji soje 13,17 kg ha-1 dan-1. Iz dobivenih rezultata, može se vidjeti kako se prosječna godišnja emisija C-CO2 smanjivala redom ozima pšenica > soja > kukuruz. U sve tri godine istraživanja, prosječne mjesečne emisije C-CO2 iz tla bile su znatno više u razdoblju kada je vegetacijski pokrov bio prisutan u odnosu na razdoblje bez njegove prisutnosti. Također, najniže prosječne godišnje vrijednosti emisije C-CO2 zabilježene su na tretmanu s crnim ugarom tijekom sve tri godine istraživanja. Primijenjena mineralna gnojidba pokazala je najveći prosječni kumulativni godišnji gubitak emisijom u atmosferu (19,6 t C ha-1), dok je tretman s primijenjenom organskom gnojidbom pokazao najveću srednju vrijednost sadržaja ugljika u tlu (64,7 t C ha-1). S obzirom na dobivene rezultate, bitno je još jednom naglasiti važnost usvajanja održivih poljoprivrednih praksi kojima će se podići razine ugljika u tlu te smanjiti gubitci kroz emisije CO2 u atmosferu.In recent, as the world's population has grown, the standard of living has risen and with it the cumulative level of greenhouse gas emissions. It is precisely the increasing emissions of greenhouse gasses caused by human activities that, through their release from the energy, industrial and agricultural sectors, lead to their accumulation in the atmosphere and to climate warming, resulting in changes in the atmosphere, on land and in the oceans. Among the numerous greenhouse gasses, carbon dioxide (CO2) is one of the most important compounds affecting global warming and is considered to be the driving force of global climate change. The carbon cycle in nature is inconceivable without soil as an essential component of the environment, confirming that soil and climate have always been closely linked. It is therefore important to emphasize that one of the most important factors in the fight against climate change is precisely the soil respectively human activity on the soil. With a carbon content multiple as high as in the atmosphere, it contributes significantly to the global carbon balance. In terrestrial ecosystems, soil respiration is therefore the key proces linking the below-above-ground carbon cycle. As the second largest global component of carbon flux in terrestrial ecosystems, soil respiration contributes significantly to the greenhouse effect. This is precisely why it is important to manage the soil properly and slow down the pace of climate change through practices such as reduced tillage, proper fertilization and optimized crop rotations in agriculture. In addition to the mentioned practices, soil temperature, soil water content, soil C:N, amount of organic matter, microorganisms, presence and type of vegetation, soil pH and other factors also contribute to soil CO2 emissions. It is also important to emphasize that the process of CO2 formation in the soil is directly related to climatic factors such as air temperature and relative humidity, which affect soil temperature and relative soil moisture and thus carbon emission and sequestration.
Soil fertilization is considered as one of the most important agricultural measures for increasing productivity and yield. The application of fertilizers is of great importance for CO2 emissions from the soil, which can vary by changing the amount and chemical composition of the fertilizer. High nitrogen concentrations in the soil, especially after mineral N fertilization, can stimulate microbial decomposition of soil organic matter, so that any transformation of organic matter results in emissions to the environment. In addition, greenhouse gas emissions caused by the application of fertilizers represent one of the more important sources of total agricultural emissions.
The motivation for the research in this doctoral thesis lies in the scientific interest to determine the impact of the carbon dioxide amount that is emitted into the atmosphere as a greenhouse gas from the soil, as a result of the agricultural practices, especially through different forms of fertilization. These findings will be the basis for planning sustainable soil management in the study region, and also in other areas with the same or similar pedological and climatic characteristics. Precisely for this reason, the research conducted in this dissertation is based on the hypothesis that: a) the C-CO2 emission from agricultural soil will depend on the type of fertilization, b) the C-CO2 emission from agricultural soil will depend on the type of crop, c) the C-CO2 emission from agricultural soil will depend on the carbon content of the soil. To prove the established hypotheses, the following objectives were set for this study: a) using field measurements, determine the dependence of soil C-CO2 emissions on the fertilization type in three years with three different arable crops, b) carry out a balance, i.e. determine the inflows and outflows of carbon from the soil for all treatments studied and determine the dependence on the C-CO2 emissions from the soil.
The research was conducted on the arable land on the Jelenščak plot, in the village Potok near Popovača, and included 10 different treatments, four of which were selected for the purposes of this dissertation. Four different treatments included: I.- control – no fertilization; II.- N250 + P + K + 40 t/ha organic solid mixed manure; III.- N300 + P + K; IV.- black fallow – cultivation without sowing. The cover crop at the experimental field in the investigated 2016 was winter wheat (Triticum aestivum L.), in 2017 corn (Zea mays L.) and in 2018 soybean (Glycine max L.). The measurement of the carbon dioxide concentration on the soil surface was carried out based on the static chamber method, and measured with a portable infrared detector of carbon dioxide GasAlerMicro5 IR (2011). Temperature (°C), electrical conductivity (dS/m) and soil moisture content (%) were measured using the IMKO HD2 instrument (Trime – Pico64 probe, 2011) at a depth of 10 cm in the vicinity of each chamber, during each CO2 concentration measurement. Air temperature (°C), relative humidity (%) and air pressure (hPa) (Testo 610, 2011 and Testo 511, 2011) were measured at each arrival and departure from the experimental field. During the research period, a total of 24 measurements of concentration and calculation of C-CO2 emissions from the soil and agroecological factors were done.
The results demonstrate a descending pattern in average annual C-CO2 emissions: winter wheat > soybean > corn. The C-CO2 emission during corn cultivation was 37,7 % lower than the emission observed during winter wheat growth, while during soybean cultivation, the emissions were 26,7 % lower compared to winter wheat vegetation and 15,0 % lower compared to corn vegetation. These results suggest variations in carbon dioxide emissions across different crops, indicating potential differences in soil carbon dynamics influenced by crop characteristics including root structure, residue composition, and overall biomass. Likewise, in all three research years, C-CO2 emissions from the soil were higher in the period when the vegetation cover was present compared to the period without its presence. The average annual values of C-CO2 emissions from the soil according to fertilization treatments were the lowest on the treatment with black fallow during all three years, and the highest on the treatments with applied organic (2016) or mineral fertilization (2017 and 2018). These results indicate that the reduction in C-CO2 emissions in the black fallow treatment can be attributed to a lack of organic matter input due to the absence of crops, and mineral and organic fertilization, which implies a reduced availability of organic materials for decomposition, consequently leading to lower CO2 emissions. During winter wheat vegetation, C-CO2 emissions varied between 1,91 kg ha-1 day-1 (black fallow) and 54,33 kg ha-1 day-1 (mineral fertilization). For corn, emissions ranged from 0,76 kg ha-1 day-1 (organic fertilization) to 38,21 kg ha-1 day-1 (mineral fertilization). In soybean cultivation, emissions varied between 2,26 kg ha-1 day-1 (black fallow) and 37,89 kg ha-1 day-1 (mineral fertilization). The applied mineral fertilization showed the highest cumulative annual loss by emission to the atmosphere (19,6 t C ha-1), followed by the organic fertilization treatment (18,4 t C ha-1), the control treatment (14,3 t C ha-1) and the black fallow treatment (9,4 t C ha-1). The organic fertilization had the highest mean soil carbon content (64,7 t C ha-1), and the highest percentage reduction in total soil carbon content was recorded in the control treatment (55,6 %). Based on the obtained results, it was determined that the emission of C-CO2 depends on a various of interdependent factors within the agricultural system. On the studied soil of limited fertility, it was evident that every aspect within the agroecosystem, including agrotechnical practices and crop selection, is important and crucial in mitigating climate change, while simultaneously preserving and achieving good agricultural production
Comparison of the nutritional composition of grain corn under different drying treatments
No full textKukuruz je jedna od gospodarski najvažnijih poljoprivrednih kultura. Zbog svoje sposobnosti prilagodbe i razvoja mnogobrojnih varijacija raširena je u cijelom svijetu. Svi dijelovi kukuruza mogu se iskoristiti u industriji hrane za ljude i životinje te mnogim drugim gospodarskim granama. Sušenje je bitan dio proizvodnje kukuruza jer direktno utječe na klijavost kod sjemenskog kukuruza te kvalitetu i očuvanje hranjivih tvari zrna kukuruza namijenjenog za konzumaciju ili daljnju preradu. U ovom radu opisuje se sastav različitih hibrida/sorata kukuruza, odnosno novi hibridni kukuruz uspoređuje se sa starim sortama bijelog i crvenog kukuruza, pod utjecajem tretmana sušenja u fluidnom sloju u fluidnoj sušnici te podtlačnim sušenjem u vakuumskoj sušnici pri temperaturama od 70°C, 80°C i 90°C i tlaku od 500 mbara do vlažnosti zrna od 14%. Prije i nakon procesa sušenja provedene su analize nutritivnog sastava odnosno određen je udio vlage, škroba, proteina i masti u zrnu.Corn (Zea mays) is one of the economically most important crops. Due to its ability to adapt and develop numerous variations, it is wide spread throughout the world. All parts of the corn plant can be used in the human and animal food industry and many other economic branches. The process of drying is an important part of corn production because it directly affects the germination of seed corn as well as the quality and the preservation of nutrients of corn intended for consumption or further processing. In this paper the composition of different hybrids/varieties of corn is described, that is, new hybrid corn is compared with old varieties of white and red corn, under the influence of fluid bed drying in a fluid bed dryer and vacuum drying in a vacuum dryer at temperatures of 70°C, 80°C and 90°C and a pressure of 500mb up to a grain moisture content of 14%. Before and after the drying treatment analyses were carried out, that is, the content of moisture, starch, protein and fat in the grain was determined
Application of additives in the meat industry
No full textAditivi su često korišteni u mesnoj industriji iz raznih tehnoloških razloga, uključujući produženje roka trajanja, poboljšanje okusa, teksture i boje, te poboljšanja sigurnosti proizvoda. Najčešće korišteni aditivi u mesnoj industriji uključuju konzervanse, antioksidanse, stabilizatore i emulgatore, bojila, arome, začine i pojačivače okusa, a njihova upotreba ovisi o proizvodu, procesu proizvodnje i zakonskoj legislativi. Kako bi se osigurala sigurnost i kvaliteta proizvoda njihova uporaba mora biti pažljivo kontrolirana. Proizvođači su dužni pridržavati se smjernica i propisa o vrstama i količinama aditiva koje mogu koristiti, te jasno označiti sve korištene aditive na deklaraciji proizvoda.Additives are often used in the meat industry for various technological reasons, including extending shelf life, improving taste, texture and colour, as well as improving product safety. The most commonly used additives in the meat industry include preservatives, antioxidants, stabilizers and emulsifiers, dyes, aromas, spices and flavor enhancers, and their use depends on the product, production process and legal requirements. In order to secure safety and quality of the product, their use must be carefully controlled. Producers are obliged to adhere to the guidelines and regulations on the type and quantity of additives that may be used and to state all additives used on the product declaration
Application of the "RESCUE Stink BUG Trap" pyramid trap in the monitoring of the species Halyomorpha halys Stal, 1855
No full textSmeđa mramorasta stjenica polifagna je invazivna vrsta azijskog podrijetla koja napada 300 biljaka domaćina te uzrokuje ekonomske štete u uzgoju ratarskih, voćarskih, povrtlarskih i ukrasnih vrsta diljem svijeta. Određivanje rokova suzbijanja temelji se na procjeni populacije štetnika, a u tu svrhu razvijene su specijalizirane lovke i vrsno specifični atraktanti za praćenje vrste. S obzirom da je stjenica relativno kratko prisutna u Hrvatskoj na tržištu je malo lovki za njezino praćenje. Za praćenje je dostupna "RESCUE Stink BUG Trap" piramidalna lovka na bazi agregacijskog feromona čija učinkovitost do sada nije bila istraživana u Republici Hrvatskoj. Stoga je cilj rada bio tvrditi učinkovitost "RESCUE Stink BUG Trap" piramidalne lovke u praćenju smeđe mramoraste stjenice na proizvodnim površinama pokušališta Maksimir. Populacija smeđe mramoraste stjenice praćena je od lipnja do studenog 2023. godine na dvije pokusne površine, voćnjak Zavoda za voćarstvo i voćnjak Zavoda za poljoprivredu zoologiju. U svaki voćnjak postavljena je po jedna "RESCUE Stink BUG Trap" piramidalna lovka i ''Pherocon BMSB kit'' prozirna ljepljiva lovka koja je služila kao kontrola. Rezultati istraživanja pokazali su da je primjenom ''RESCUE Stink BUG Trap'' piramidalnih lovki i ''Pherocon BMSB kit'' prozirnih ljepljivih lovki utvrđena slična sezonska dinamika ulova odraslih i ličinačkih stadija štetnika u istraživanim voćnjacima. Na kontrolnim ''Pherocon BMSB kit'' prozirnim ljepljivim lovkama ulovljeno je 20 % više odraslih te 60 % više ličinačkih stadija štetnika. Razlike u ulovu između dviju lovki vjerojatno su nastale zbog razlika u djelotvornosti ispitivanih agregacijskih atraktanata. Temeljem prikupljenih podataka moguće je donijeti pretpostavke o razvoju dvije generacije štetnika na području istraživanja što je potrebno dokazati istraživanjem životnog ciklusa štetnika. Rezultate istraživanja potrebno je potvrditi u narednim vegetacijskim sezonama postavljanjem većeg broja lovki u kombinaciji s feromonom koji je pokazao veću djelotvornost u privlačenju vrste kako bismo uspostavili djelotvornu metodu praćenja štetnika u Republici Hrvatskoj.The brown marmorated stink bug is a polyphagous invasive species of Asian origin that attacks 300 host plants and causes economic damage in the cultivation of field crops, fruits, vegetables and ornamental species worldwide. The timing of control measures is based on pest population assessment and specialized traps and species-specific attractants have been developed for this purpose. Since the stink bug has been present in Croatia for a relatively short time, traps for its monitoring are not widely available on the market. The “RESCUE Stink BUG Trap”, a pyramid trap based on aggregation pheromone, is available for monitoring, but its effectiveness has not yet been investigated in the Republic of Croatia. Therefore, the aim of this study was to determine the effectiveness of the “RESCUE Stink BUG Trap” pyramid trap in the monitoring of the brown marmorated stink bug on the production areas of the Maksimir experimental station. The population of the brown marmorated stink bug was monitored from June to November 2023. on two experimental plots, the orchard of the Department of Pomology and the orchard of the Department of Agricultural Zoology, at the Maksimir experimental station of the University of Zagreb, Faculty of Agriculture. One “RESCUE Stink BUG Trap” pyramid trap and one “Pherocon BMSB kit” transparent sticky trap, which served as a control, were placed in each orchard. The research results showed that the application of “RESCUE Stink BUG Trap” and “Pherocon BMSB kit” transparent sticky traps determined a similar seasonal dynamic of adult and nymphal stages of the pest in the investigated orchards of the Maksimir experimental station. The control “Pherocon BMSB kit” transparent sticky traps caught 20% more adults and 60% more nymphal stages of the pest. The differences in catches between the two traps are likely due to differences in the effectiveness of the tested aggregation attractants. Based on the collected data, it is possible to make basic assumptions about the development of two generations of the pest in the research area, which needs to be confirmed by studying the pest’s life cycle. The research results need to be confirmed in the coming growing seasons by setting up a larger number of traps in combination with the pheromone that has shown greater effectiveness in attracting the species to establish an effective pest monitoring method in the Republic of Croatia
Risk management in conventional and organic vegetable production
No full textEkološka poljoprivreda, koja se oslanja na održive i ekološki prihvatljive prakse, doživljava porast potražnje za svojim proizvodima. Europska unija, a posebno Hrvatska kroz Nacionalni akcijski plan razvoja ekološke poljoprivrede 2023.-2030., pridaje značaj ovom sektoru. Europski zeleni plan nastoji odgovoriti na klimatske promjene i degradaciju okoliša, promovirajući održivije gospodarske i društvene modele te ciljajući na klimatsku neutralnost do 2050. godine. S obzirom na rastuću važnost ekološke poljoprivrede, ključno je analizirati razlike u upravljanju rizicima između konvencionalne i ekološke proizvodnje, kao i usporediti njihove proizvodno-ekonomske pokazatelje.
Cilj rada je analizirati rizike koji utječu na proizvodnju povrća i istražiti strategije koje primjenjuju konvencionalni i ekološki proizvođači. Također, rad će obuhvatiti izračun osnovnih ekonomskih pokazatelja proizvodnje povrća kako bi se usporedili rezultati između ovih dviju grupa proizvođača. Ova analiza pružit će uvid u izazove i prakse koje oblikuju sektor povrća.
Korištene su metode primarnog i sekundarnog istraživanja. Metodom studije slučaja prikupili su se podaci jednog konvencionalnog i jednog ekološkog proizvođača kupusnjača s područja Jadranske Hrvatske i jednog konvencionalnog i jednog ekološkog s područja Kontinentalne Hrvatske.
Istraživanje pokazuje da se poljoprivredni proizvođači suočavaju s umjerenim do velikim izazovima, kao što su napadi insekata, bolesti i rast cijena inputa, dok su rizici poput potresa i nedostatka zemljišta manji problem. Razlike među proizvođačima postoje ovisno o geografskom području i metodama proizvodnje. Ključne strategije uključuju korištenje otpornijih kultura i navodnjavanje, pri čemu konvencionalni proizvođači ističu važnost osiguranja. Iako sva gospodarstva ostvaruju pozitivne financijske rezultate, rentabilnost, osobito kod ekoloških proizvođača, ostaje niska, a Jadranska Hrvatska ima niže točke pokrića u odnosu na Kontinentalnu Hrvatsku.Organic farming, which relies on sustainable and environmentally-friendly practices, is experiencing a growing demand for its products. The European Union, and particularly Croatia through the National Action Plan for the Development of Organic Farming 2023 2030, places significant importance on this sector. The European Green Deal aims to address climate change and environmental degradation by promoting more sustainable economic and social models, targeting climate neutrality by 2050. Given the increasing significance of organic farming, it is crucial to analyze the differences in risk management between conventional and organic production, as well as to compare their production-economic indicators.
The aim of this study is to analyze the risks affecting vegetable production and to explore the strategies employed by both conventional and ecological producers. Additionally, the study will include the calculation of basic economic indicators of vegetable production to compare the results between these two groups of producers. This analysis will provide insights into the challenges and practices shaping the vegetable sector.
Methods of primary and secondary research were used. Data was collected through a case study of one conventional and one organic cabbage producer from the Adriatic region of Croatia, as well as one conventional and one organic producer from the Continental region of Croatia.
The research shows that agricultural producers face moderate to significant challenges, such as insect attacks, diseases, and rising input prices, while risks like earthquakes and land scarcity are less of a concern. Differences among producers exist depending on the geographical area and production methods. Key strategies include the use of more resilient crops and irrigation, with conventional producers emphasizing the importance of insurance. Although all farms achieve positive financial results, profitability, particularly among organic producers, remains low, and the Adriatic region of Croatia has lower break-even points compared to the Continental region
Management of agricultural practices for the cultivation of nettle (Urtica dioica L.) with modern hydroponic techniques
No full textUzgoj hrane postaje sve zahtjevniji zbog klimatskih promjena koje negativno utječu na poljoprivredne prinose, ali i na kvalitetu i nutritivnu vrijednost namirnica. Uvođenje zanemarenih biljnih vrsta u proizvodnju s ciljem očuvanja bioraznolikosti i sigurnosti hrane jedno je od održivih rješenja za sve veće izazove s kojima se današnja poljoprivreda susreće. Kopriva je višegodišnja biljna vrsta bogata specijaliziranim metabolitima prepoznata po brojnim biološkim i funkcionalnim svojstvima značajnim za zdravlje ljudi. Iako raste samoniklo u prirodi, teži se uvođenju koprive u poljoprivrednu proizvodnju u svrhu dobivanja proizvoda ujednačene kvalitete. Hidroponski uzgoj koprive u zaštićenom prostoru još uvijek nije raširen, unatoč brojnim prednostima koje ima u odnosu na uzgoj na tlu, uključujući smanjenje mnogih rizika povezanih s proizvodnjom na otvorenom. Takav način uzgoja pruža mogućnost upravljanja abiotskim čimbenicima zraka (temperatura i relativna vlaga zraka) i hranive otopine (pH, elektroprovodljivost, koncentracija otopljenog kisika i temperatura), dok se odabranim agrotehničkim mjerama, poput balansirane gnojidbe i upravljanja režimom navodnjavanja, može utjecati na prinose i sadržaj specijaliziranih metabolita u biljnom materijalu. Ovaj način uzgoja također pruža mogućnost cjelogodišnje proizvodnje tijekom mjeseci kada to na otvorenom ne bi bilo moguće. Cilj ovog doktorskog rada bio je istražiti utjecaj četiri hranive otopine različitog sastava i dva režima navodnjavanja na agronomske karakteristike, količinu nitrata i sadržaj specijaliziranih metabolita te antioksidacijski kapacitet svježeg lista koprive. Biljke koprive uzgajane su u hidroponskom sustavu koristeći tehnike plutajući hidropon (FH) te dotjecanje i otjecanje (EF). Dva jednofaktorijalna pokusa provedena su s hranivom otopinom i režimom navodnjavanja kao faktorima u proljetno-ljetnom roku uzgoja, a postavljeni su po metodi slučajnog bloknog rasporeda u 3 ponavljanja. Pri uzgoju koprive tehnikom FH ostvarene su tri košnje, dok je pri uzgoju tehnikom EF ostvareno osam košnji od kojih je šest košnji uključeno u ovo istraživanje. Uzgoj koprive tehnikom FH u hranivoj otopini EC vrijednosti 1,7 mS/cm rezultirao je biljnim materijalom prosječno viših vrijednosti suhe tvari (19,92 % ST), sadržaja askorbinske kiseline (91,73 mg/100 g sv.t.) i ukupnih fenola (309,59 mg GAE/100 g), dok je uzgoj u hranivoj otopini EC vrijednosti 1,5 mS/cm rezultirao najvećim kumulativnim prinosom (4,2 kg/m2) uz najnižu prosječnu količinu nitrata u svježem listu koprive (5069 mg/kg NO3-). Antioksidacijski kapacitet listova koprive prema FRAP metodi iznosio je od 963,27 do 3237,62 μmol TE/L tijekom uzgoja tehnikom FH. Uzgoj koprive tehnikom EF uz režim navodnjavanja svaka 72 h rezultirao je višim vrijednostima svih agronomskih karakteristika koprive tijekom cijelog razdoblja uzgoja, osim u petom vegetacijskom periodu. Režim navodnjavanja svakih 48 h pozitivno je utjecao na sadržaj askorbinske kiseline, ukupnih fenola, neflavonoida i flavonoida (prosječno 98,80 mg/100 g sv.t., 245,73 mg GAE/100 g, 128,33 mg GAE/100 g, 117,40 mg GAE/100 g) te je rezultirao nižim količinama nitrata u listu koprive (prosječno 3570 mg/kg NO3-). Vrijednostiantioksidacijskog kapaciteta tijekom uzgoja tehnikom EF bile su više od onih utvrđenih pri uzgoju tehnikom FH, što potvrđuje kako je list koprive uzgajane tehnikom EF izvrstan izvor antioksidansa. Ovo istraživanje pokazalo je kako su obje istraživane tehnike hidroponskog uzgoja (FH i EF) perspektivne za uzgoj koprive. Međutim, tehnika EF, u kombinaciji s optimiziranim režimom navodnjavanja i sastavom hranive otopine, može značajno povećati prinos i kvalitetu lista koprive. Za postizanje optimalnog prinosa listova koprive visoke nutritivne vrijednosti u hidroponskom uzgoju, preporučuje se korištenje hranive otopine EC vrijednosti 1,5 mS/cm i tehnike EF uz režim navodnjavanja svaka 72 h.Growing food is becoming more challenging due to climate change, which has a
negative impact on food quality, nutritional value and yields. A sustainable solution to the
challenges of modern agriculture is to adopt agricultural practices with a low environmental
footprint while preserving biodiversity and ensuring food security by introducing foods with
high nutritional value. At the same time, today's consumers are looking for novel, highly
nutritious foods that enhance their overall health and well-being. Stinging nettle (Urtica dioica
L.) is recognized not only as a medicinal plant, but also as a desirable green leafy vegetable
rich in phytonutrients, demonstrating its significant potential for human nutrition. Stinging nettle
is a perennial plant species with a high content of specialized metabolites and known for their
numerous biological and functional properties that benefit human health. Although it grows
wild, efforts are being made to introduce stinging nettle into agricultural production in order to
obtain uniform quality and safe plant material. Hydroponic cultivation of nettle, although not
yet widespread, offers numerous advantages over soil cultivation, including reduced risks
associated with outdoor production. This method allows the management of abiotic factors
such as air temperature and relative humidity, as well as nutrient solution parameters such as
pH, electrical conductivity, dissolved oxygen and temperature. In addition, selected
agrotechnical measures such as balanced fertilization and controlled irrigation regimes can
influence the morphological characteristics and yield but also the content of specialized
metabolites in the plant material. Hydroponic cultivation also enables year-round production
in a completely closed system that maximizes the use of resources and energy, creating a
circular system and thus greater sustainability and resilience of the entire cultivation system.
The aim of this PhD thesis was to investigate the possibilities of nettle cultivation in a
hydroponic system, respectively in floating system and ebb and flow system, and to investigate
the influence of four nutrient solutions with different compositions of macro and micronutrients
and two irrigation regimes on the agronomic properties, nitrate quantity and content of
specialized metabolites as well as the antioxidant capacity of fresh nettle leaves.
The nettle was grown in a hydroponic system using Floating Hydroponic (FH) and Ebb
and Flow (EF) techniques. Two monofactorial experiments were conducted in the springsummer
growing period, with nutrient solution and irrigation regime as factors, laid out in 3
replicates using the randomized block design method. During the cultivation period, the abiotic
factors of the greenhouse and the nutrient solution were continuously monitored and adjusted
if necessary. In the cultivation of stinging nettle using the FH technique, 3 consecutive cuts
were obtained, while in the cultivation using the EF technique, 8 consecutive cuts were
obtained, 6 of which were analyzed for the purposes of this study. Morphological and chemical
analyses of the plant material were carried out after each consecutive cut.
Cultivation of stinging nettle using the FH technique in a nutrient solution with an EC
value of 1.7 mS/cm resulted in plant material with higher average values for dry matter
(19.92% DM), ascorbic acid content (91.73 mg/100 g fw) and total phenols (309.59 mg
GAE/100 g), while cultivation in a nutrient solution with an EC value of 1.5 mS/cm resulted in
the highest cumulative yield (4.2 kg/m2) with the lowest average amount of nitrate in fresh
nettle leaves (5069 mg/kg NO3-). The antioxidant capacity of nettle leaves using the FRAP
method ranged from 963.27 to 3237.62 μmol TE/L using the FH technique. Cultivation of nettle
using the EF technique with irrigation every 72 h resulted in higher values of all nettle
agronomic traits in all six vegetation periods, except in the fifth vegetation period. Irrigation
every 48 h had a positive effect on the content of ascorbic acid, total phenols, non-flavonoids
and flavonoids (average 98.80 mg/100 g fw, 245.73 mg GAE/100 g, 128.33 mg GAE/100 g,
117.40 mg GAE/100 g) and resulted in lower nitrate levels in the nettle leaves (average 3570
mg/kg NO3 -). The antioxidant capacity value was higher when cultivated using the EF
technique than when cultivated using the FH technique, confirming that nettle leaves obtained
by cultivation in the EF hydroponic system are an excellent source of antioxidants.
This study has shown that both hydroponic cultivation techniques investigated (FH and
EF) prove to be promising hydroponic techniques for the cultivation of nettle. However, the EF
technique, in combination with an optimized irrigation regime and nutrient solution content,
can significantly improve the yield and quality of nettle leaves. To achieve an optimal yield of
nettle leaves with high nutritional value in hydroponic cultivation, it is recommended to use a
nutrient solution with an EC value of 1.5 mS/cm and an EF technique with an irrigation regime
every 72 h.
The results of this research will expand the existing knowledge on the possibilities of
growing nettle with modern hydroponic techniques and provide recommendations for the
composition of the nutrient solution and the irrigation regime that will lead to an optimal yield
and high nutritional quality of the fresh plant material. This research also provides an important
scientific contribution on the role and effect of water stress on the increase in the content of
specialized metabolites in the fresh nettle leaf with the aim of obtaining nutrient-rich plant
material. These results will serve as a basis for further research in the field of growing
vegetable, medicinal and aromatic plants using modern hydroponic techniques
