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Several research papers emphasize that both species composition and land cover in Mediterranean ecosystems generally recover rapidly after fire. Mediterranean species have ecological strategies for the post-fire period, such as the ability to resprout, seed bank persistence, or the ability to grow or disperse. Here an abandoned agricultural field (AAF) near Biograd na moru (Croatia) was burned by an induced fire. Fifteen rings (diameter 0.2 m2 ) were established, five for each variant: I. unburned (UB), II. medium intensity (MB) and III. high intensity (HB), and observed within 12 months. The results showed that the functional group (FG) of grasses dominated in the variant MB, in contrast to the dominance of legumes in the variant HB. Compared to AAF, the number of forbs FG slightly decreased in both burn variants (MB, HB). The dominant strategy was competitors (C), followed by ruderal plants (R), whose numbers increased slightly after burning in the MB and HB variants, while stress tolerants decreased significantly in both variants. The total cover of renewed vegetation was higher on HB than on MB. These preliminary results indicate that the intensity of HB does not promote grass survival in the first year after fire, while legumes and forbs are more resistant to higher fire intensity and therefore have a higher chance of survival. Acknowledgements: This research was supported by the Croatian science foundation under the project “Influence of Summer Fire on Soil and Water Quality” (IP-2018- 01-1645).

A neglected arable agricultural area near the town of Vrana near Lake Vrana was burned by an induced fire. The area is located in the transition zone between evergreen (Fraxino orni - Quercetum ilicis) and deciduous vegetation (Querco- Carpinetum orientalis). The agricultural site itself, immediately around the burned area of the experiment, is dominated by Mediterranean maquis with the characteristic species Pistacia lentiscus and the monoculture community of Foeniculum vulgare. The studied area is divided into three experimental variants (average slope 18%): I. (control - anthropogenic meadow), II. (lower intensity burning, burning 10 kg/m2 of straw) and III. ( higher intensity burning, burning 10 kg/m2 of straw and 15 kg of vine wood). Fifteen rings (diameter 0.2 m2) were established on the studied area, five on each variant. The growth and development of flora and vegetation were observed monthly. All inventoried plant species were identified, herbarized, digitised, and are available in the ZAGR online herbarium (http://herbarium.agr.hr/hr_search.html). Abundant growth of plant taxa from all three functional groups that follow different ecological survival strategies was observed on the control variant: legumes, forbs, and graminoids. The most abundant species included the very species that were recorded within the experimental rings, but also included several others that were not previously recorded in the burned experimental rings (Plantago lanceolata, Urospermum picroides, Sisymbrium officinale, Silene latifolia ssp. alba). On the variant with lower fire intensity, the dominance of monocotyledons from the Poaceae family is visible: Avena sativa, Dactylis glomerata, Hordeum murinum, Elymus repens and others. On the variant with higher fire intensity, the dominance of plants from the group and family of legumes (Fabaceae) was observed, for example, Vicia cracca, Vicia sativa and Lathyrus aphaca. Compared to the control variant, abundant plants from the forage functional group grew in both burn variants (higher and lower intensity): Foeniculum vulgare, Convolvulus arvensis, and C. cantabrica, which were also the first to emerge three weeks after the 2019 induced burn. Total cover of renewed vegetation did not exceed 25% at either fire intensity after 24 months. Based on this results, we conclude that higher fire intensity does not promote survival of therophyte (monocotyledonous) life form, while hemicryptophytes and hamephytes (dicotyledonous) are more resistant to higher fire intensity and therefore have a greater possibility of survival.

Agrokemija, znanstvena grana u polju poljoprivrede, koja obuhvaća poznavanje, razumijevanje i primjenu kemije u agronomiji (poljoprivredi)....

Paleoclimate studies for long-term records are often obtained from speleothems fed with very slow drips that have a diffusional flow and consequently a limited amount of water available for monitoring studies. Using a HOBO U24-001 data logger, we have implemented a methodology for measuring electrical conductivity (EC) in drip water samples with volume

The three greenhouse gases (GHGs) associated with agriculture include carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). While the CO2 represents the major GHG issue for the total economy, N2O, even though is a small part of the overall GHG issue, becomes the most important for agriculture considering soil management and fertilizer use. This research, conducted in a conventional agroecosystem under triticale vegetation in Popovaca, was based on measurement of CO2 and NO2 emissions using a static chambers for CO2 and method with passive samplers and static chambers for NO2. The aim of this study was to determine the amount of C-CO2 emitted from the soil into the atmosphere, depending on different amounts of nitrogen fertilizer (0-300 kg N/ha) during the vegetation. Also, the aim was to determine the suitability of the selected method for N-NO2 concentration measurement and to determine the potential impact of mineral fertilization on the N-NO2 emission (0 and 300 kg N/ha). Mean annual values of C-CO2 emissions ranged from 10.4 kg/ha×day on the treatment X (black fallow) up to 26.1 kg/ha×day on the control treatment (I) and treatment with 250 kg N/ha (VI). A weak correlation between the amount of nitrogen (0-300 kg/ha) and the emission of C-CO2 was determined (r = 0.26). The used method was suitable for N-NO2 concentration. Measured daily values of N-NO2 emission ranged from 1.66 to 7.18 mg/ha per day, depending on phenophase and treatment. Statistically significant differences in N-NO2 emission between two monitored treatments (300 kg N and 0 kg N) were not observed.

Anthropogenic climate change is altering ecological and human systems globally, including national parks that conserve unique but vulnerable ecosystems and biodiversity. Yet the magnitude and spatial patterns of climate change across national parks are generally unknown. The National Park (NP) Brijuni in Croatia encompasses 14 islands and islets covering an area of 33.9 km2 in the northern Adriatic Sea, representing a unique microenvironment with a specific biodiversity, natural, cultural and historical features. Due to its location, NP Brijuni is in direct threat of potentially strong air pollution from regional and long-range sources from continental Europe. However, the atmospheric pollution impacts to the area of the NP Brijuni have been unknown. This work presents the first insight into the air pollution sources, its seasonal variabilities as well as atmospheric deposition impacts to the area of NP Brijuni. The sampling campaign at NP Brijuni was conducted from June to November 2020 and included on-line measurements of black carbon (BC) concentrations and collection of particulate matter (PM10), wet and total deposition samples. The results of BC concentrations and its source apportionment and dataset comprising dominant ions (NO3-, SO42-, Cl-, Na+, K+, Ca2+, Mg2+, NH4+) and organic matter (organic carbon and water soluble organic carbon) in PM10 and deposition samples were statistically analysed and discussed considering different seasons, meteorological conditions and specific air-mass inputs in order to better understand the extent of the changing environment as a main prerequisites for air quality management, planning and implementation of appropriate environmental protection measures in the NP Brijuni. Acknowledgment: This work has been supported by National Park Brijuni under the „Insight into the variability and composition of atmospheric deposition in the area of Brijuni National Park“ project, and by and Croatian Science Foundation under the IP-2018-01-3105 BiREADI project.

Klimatske promjene jedan su od najvećih izazova s kojima se danas suočavamo. Sektor poljoprivrede predstavlja jedan od većih izvora emisija stakleničkih plinova kako u svijetu tako i u Hrvatskoj, a koje izravno utječu na sve veći problem klimatskih promjena. Jedan od glavnih čimbenika u borbi protiv njih je upravo tlo koje sadrži dva puta više ugljika u odnosu na atmosferu i stoga predstavlja važnu komponentu globalnog proračuna za ugljik. Ovisno o tome kako se njime gospodari, tlo može imati ulogu izvora ili skladišta C i N. Cilj ovog istraživanja bio je izmjeriti i prikazati količinu emitiranog C-CO2 iz poljoprivrednog tla te usporediti međusobnu ovisnost C-CO2 emisije o temperaturi i vlažnosti tla. Pokusno polje s 10 različitih gnojidbenih tretmana postavljeno je u središnjem dijelu Hrvatske, u Popovači, na dubokom distričnom pseudogleju u svrhu mjerenja emisija C-CO2 iz tla. Mjerenje koncentracije CO2 u tlu provedeno je metodom statičkih komora 8 puta tijekom vegetacijske godine u tri ponavljanja na svakom tretmanu. U neposrednoj blizini svake komore mjerili su se i parametri tla (temperatura, vlaga i elektrovodljivost). Prosječne godišnje vrijednosti C-CO2 kretale su se od 2, 7 kg ha-1×dan do 28, 9 kg ha-1×dan. Zabilježena je slaba pozitivna korelacija između prosječnih godišnjih vrijednosti C-CO2 i temperature tla, kao i između vrijednosti C-CO2 i vlage u tlu.

One of the most significant questions of the world that struggles with how to address climate change is how to reduce increasing levels of carbon dioxide (CO2) in the atmosphere. One of the strategies for climate change mitigation is carbon sequestration i.e. storing of atmospheric carbon (C) into the plant/soil pool. This accomplishes not only the aim of reducing levels of atmospheric CO2 but it is also improving soil health, leading to higher yields, nutrient contents and other agroecological benefits. The relationship between carbon sequestration and plant/soil carbon input is complex and depends on many elements like land use types i.e. crop type and cultivar, soil properties, agrotechnical measures, etc. Therefore, the aim of this study is to determine the biomass yields and carbon sequestration potentials of two arable crops (winter wheat and winter barley) and their four different cultivars. In order to determine biomass yields, biomass carbon contents and sequestration potentials, four different cultivars of winter wheat (Srpanjka, Renata, El Nino, Kraljica) and winter barley (Rex, Lord, Barun, Panonac) were destructively harvested at three randomly chosen 1 m2 of each cultivar in continental part of Croatia at 2021 harvest. In this study, the above-ground (grain and straw: stems + leaves + chaff) and below-ground (roots + stubble) biomass yields, the allocation of atmospheric carbon within biomass and sequestration potentials od each cultivar will be presented.

Streljane i upotreba vatrenog oružja izvor su onečišćenja tla i okoliša, ali i rizika za zdravlje divljih životinja i ljudi. Krajem 2021. Europska agencija za kemikalije uputila je prijedlog EK za ograničenje upotrebe Pb na otvorenim prostorima upravo zbog dokazane toksičnosti na ekosustav. Kod disciplina streljaštva na leteće glinene golubove većinom se koristi streljivo s olovnom sačmom. Na streljani Luže u blizini Zagreba, a koja se koristi samo za olimpijske discipline Trap i Skeet, 2020. uzorkovano je tlo na dvije piste (C i D). Na prvoj streljačkoj pisti (C - koja se koristi od 1989.) godišnje se iskoristi oko 7 paleta meta, a na drugoj pisti (D - koja se koristi od 2006.) iskoristi se 5 paleta meta godišnje. Jedna paleta sadrži 8250 meta. Prosječno se po paleti iskoristi 11 000 komada streljiva, a svaki metak u prosjeku sadrži 24 g olovne sačme te 1, 3 g baruta. Iz toga proizlazi da na pisti C dolazi do transfera 1848 kg olova i 100, 1 kg baruta u okolni ekosustav, a na pisti D 1320 kg Pb i 71, 5 kg baruta godišnje. Cilj ovog rada bio je utvrditi sadržaj i prostornu varijabilnost koncentracije metala (Pb, Sb, Cu, Zn, Ni) u tlu na dvije piste streljane Luže, obzirom na utjecaj razdoblja korištenja piste i udaljenosti (-40 m, +5 m, +25 m, +50 m, +100 m, +240 m) od pozicije pucanja (0 m). Dugogodišnje korištenje streljane rezultiralo je da koncentracije nekih metala u tlu prelaze MDK (NN 71/19) za poljoprivredna tla (Pb, Sb, Ni i Zn na 100 m, te Pb na 50 m). Vrijednosti koncentracija Pb i Sb izmjerene na 100 m prelaze i intervencijsku vrijednost (Rijkswaterstaat Environment/2013) te zahtijevaju sanaciju. Utvrđena je i vrlo jaka korelacija između udaljenosti i kiselosti tla. Zabilježen je pad od čak 2, 14 pH jedinica na 100 m u odnosu na prirodno okolno tlo (-40 m i +240 m).

Radi održivosti uzgoja proteina u svijetu, sve se više potiče uzgoj insekata. U uzgoju nastaju nusproizvodi među kojima su ekskrementi insekata koji se nalaze na tržištu te predstavljaju tip poboljšivača tla. Njihova kvaliteta i efikasnost znanstveno su malo ispitani. Cilj rada bio je utvrditi kemijski sastav izmeta šturka (Gryllus assimilis Fab.) te efikasnost njegove primjene kao poboljšivača tla u poljskim uvjetima uzgoja salate (Lactuca sativa L.). Primjena izmeta šturka je pozitivno utjecala na tlo i kemijski sastav biljke ali nisu ustanovljeni statistički značajni rezultati u prinosima. Utvrđen NPK omjer šturkovog izmeta iznosio je 5:1:4.

Prescribed fire in pre-mountain Croatia is a widespread traditional agricultural practice used in late winter or early spring mainly for weed control. Prescribed fire turns vegetation into ash, the nutrients of which are either leached into the soil or removed by erosion, depending on climatic conditions (rain and wind). The ash contains high quantities of nutrients that depend on the species burned. Although, due to its frequent use in this region, there is a lack of information on the effects of this type of fire on the spatial-temporal vegetation regrowth and soil chemical properties. To address this issue, a prescribed fire was conducted on an experimental plot (30 m long x 35 m wide) with slight differences in slope gradient on March 2, 2021. The experiment is located in the hinterland of Otočac City (44°52'N 15°14'E ; 490 m a.s.l.). Soil type of study area is Cambisols. The vegetation cover consisted of various species such as meadow plants, fern (Pteridium aquilinum), blackberry (Rubus fruticosus), and dogberry tree (Cornus mas). Soil sampling (6 points in 5 rows) and vegetation cover monitoring were conducted immediately before fire (IBF), 7 days after fire (DAF), 1, 3, and 6 months after fire (MAF). The variables studied were: vegetation cover (VC), soil pH, EC, and total content of Al, Si, P, S, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, As, Rb, Sr, Y, Zr, Nb, Pb, and Th. After a prescribed fire, VC was gradually increased with full cover on each sampling point 3 MAF. Significantly higher increase in soil pH, EC, and P was observed 7 DAB compared to the other dates. The studied soil elements did not show much variability in spatial distribution, indicating low severity fire and low impact of erosion. Principal component analysis (PCA) was applied to identify the relationship among study soil properties and VC for each sampling date. Overall, PCA showed that prescribed fire changed the relationship between the studied variables at each date, especially in the case of VC, pH, EC, Ca, P, K, Al, Mn, and Co which can be attributed to the effects of rainfall during the study period. Due to the low impact on the spatial-temporal variability of topsoil elements and the rapid vegetation regrowth, prescribed fire can be recommended for land management.

Knowledge and understanding of carbon and nitrogen biogeochemical cycles in agroecosystems are crucial for a global sustainable management and development. Nitrogen and carbon forms and compounds cycle between pedosphere, hydrosphere and atmosphere. This includes a very wide range of complex reactions which are influenced by many factors. From abiotic, like temperature and sunlight, through biotic (microorganisms) up to anthropogenic, including different agricultural practices (fertilization, tillage, drainage). Nitrogen oxides (NxOy) ammonia (NH3), carbon oxide (CO2) and methane (CH4) emissions from the agricultural sector contribute with more than 10 % in total GHGs emissions. Some of them are primary pollutants (NOx, NH3) or directly affect the greenhouse effect (N2O, CH4, CO2) and some of them contribute in producing secondary pollutants (NOx, NH3) and GHG like O3 or N2O. The methods used for air quality (NxOy) measurement are assigned to 4 categories: (1) passive sampler methods ; (2) active methods ; (3) automatic methods and (4) remote sensing methods. All of them have advantages and disadvantages. This research, which was conducted in a conventional agroecosystem under triticale vegetation, in a field experiment in Croatia, was based on measurement of nitrogen oxide emissions, by using a method with passive samplers and static chambers which we have developed. The aim of the study was to determine the suitability of the selected method for N-NO2 concentration measurement. It was presumed that, if measured concentration was higher than the limit of detection (LOD), it was possible to determine the potential impact of mineral fertilization on the N-NO2 emission (two treatments with 0 and 300 kg N/ha). Also, the intention was to compare N-NO2 emission between two sets of measurements in phenophases (tillering and jointing) of triticale. The research had shown that the used method was suitable for N-NO2 concentration measurement (measured concentrations were above LOD). Measured daily values of N-NO2 emission ranged from 1.66 to 7.18 mg/ha per day, depending on phenophase and treatment. Statistically significant differences in N-NO2 emission between two monitored treatments (300 kg N and 0 kg N) were not observed, as well as between two investigated phenophases. Soil temperature in March 2014 (22.3 °C) was significantly higher than in April 2014 (10.9 °C). Average cumulative annual flux was 1.15 g/ha per year and 1.55 g/ha per year, respectively, depending on the treatment.

Carbon dioxide (CO2) emissions from terrestrial ecosystems represent one of the most important contributors to climate change. It is considered that most of the carbon released to the atmosphere is originated through agricultural activities that mainly increased since the industrial revolution where irresponsible land management often leads to soil carbon loss and increased carbon dioxide emissions to the atmosphere. Likewise, agricultural management practices that include changing the soil environment affect soil CO2 flux. The objective of this study was to determine the influence of different fertilization in soybean agro ecosystem on CO2 respiration. The field experiment with four different fertilization treatments was set up in central part of Croatia (N 45° 33' 21.42'', E 16° 31' 44.62'') on deep, distric pseudogley (Stagnosol). It contains four different fertilization treatments as follows: (I) control treatment – no fertilization, (II) organic fertilization – 40 t ha−1 of solid farmyard mixed manure + P + K, (III) mineral fertilization – 300 kg ha−1 N + P + K and (IV) black fallow – no vegetation. The cover crop at the experimental field in the investigated year (2018) was soybean (Glycine max L.– Tena variety) which was sown on 27th April 2018 and harvested on 26th September 2018. The experimental plot is characterized by continental climate. In the studied year (2018) mean amount of precipitation was 824.5 mm with mean temperature of 12.7 °C. The measurements of soil CO2 concentrations and soil properties were conducted eight times during the vegetation year (January, March, April, May, June, July, August and September) in three repetitions on each treatment. The soil CO2 concentrations were measured by a closed static chamber method with incubation time of 30 minutes. After 30 minutes, the soil CO2 concentrations were measured with portable infrared CO2 detector (GasAlerMicro5 IR, 2011). The soil carbon dioxide flux was expressed as kg C-CO2 per ha per day. At the beginning and the end of each measurement, air temperature and relative air humidity were measured with Testo 610 (2011) and air pressure with Testo 511 (2011). Soil properties (temperature and moisture) were measured with IMKO HD2 – probe Trime, Pico64, 2011 at 10 cm depth in the vicinity of the chambers in three replications. Depending on fertilization treatment, mean annual C-CO2 flux ranged from 7.7 kg ha-1 day-1 on black fallow to 16.7 kg ha-1 day-1 on treatment with mineral fertilization and were significantly different (SAS 9.1 p

Mnogobrojna istraživanja ukazuju da dugotrajna primjena fungicida na bazi bakra uzrokuje onečišćenje poljoprivrednih tala navedenim metalom. Cilj ovog rada bio je utvrditi utjecaj nagiba padine i različitog načina korištenja tla na prostornu akumulaciju bakra u poljoprivrednim tlima. Istraživanje je provedeno u listopadu 2019. godine u sjeverozapadnoj Hrvatskoj na površini smještenoj na padini koja obuhvaća: dva vinograda (zatravljeni i nezatravljeni), oranicu i livadu. U površinskim (0-10 cm) prosječnim uzorcima tla nakon digestije zlatotopkom sadržaj bakra utvrđen je primjenom atomske apsorpcijske spektrometrije (AAS metodom). Provedena istraživanja ukazuju da je nagib padine pridonio varijabilnosti bakra u tlu, koja se značajno smanjivala od vrha padine gdje su smješteni vinogradi do podnožja na kojem se nalazi oranica i livada. Rezultati dodatno potvrđuju i na djelovanja erozije vodom koja je imala utjecaj na sadržaj bakra u tlu oranice prostorno smještene na padini ispod vinograda. Uvažavajući propisanu nacionalnu legislativu (MDK 120 mg kg-1 ; NN 71/2019) može se zaključiti da je u tlu oba vinograda zabilježen nedozvoljeni sadržaj bakra (135-272 mg/kg), te da je u nastavku padine u tlu oranice i livade utvrđen prihvatljiv sadržaj bakra (40, 1-82, 0 mg/kg). Dodatno, značajno viši sadržaj bakra u tlu zatravljenog vinograda (245 mg/kg) u odnosu na nezatravljeni vinograd (140 mg/kg) djelomično je uzrokovan višim sadržajem organske tvari u zatravljenom vinogradu.

As a source of greenhouse gas emissions, the agricultural sector directly affects the global problem of climate change. A research study was conducted in Western Pannonian sub-region of Croatia to measure soil respiration and its seasonal variability influenced by vegetation presence (maize - Zea mays L.). Soil C-CO2 flux was measured 14 times during the investigated period in a field experiment with 4 different fertilization treatments. Average daily C-CO2 flux was the highest in June 2017 (38.2 kg ha-1 day-1) and the lowest in November 2017 (0.76 kg ha-1 day-1). The results imply that season and vegetation presence has a significant effect on soil respiration rates.

The anthropogenic emission of greenhouse gases including carbon dioxide, methane, and nitrous oxide is bringing about major changes to the global environment. Although most of the anthropogenic emissions originate from industrial processes, agriculture is responsible for a significant portion of the greenhouse gases produced by humans worldwide. The impact of agriculture has become a key issue, considering that the main greenhouse gases are those related to carbon and nitrogen global cycles. This paper presents a review of the scientific literature meant to provide the impact of human management through fertilizers use on CO2, CH4, and N2O emissions. The influence of organic and mineral fertilization on greenhouse gas emissions is analyzed, and usage of organic amendments showed a wise potential for protecting the environment and to mitigate greenhouse gas emissions.