Potential Hazard of Open Space Fire in Black Pine Stands (Pinus nigra J.F. Arnold) in Regard to Fire Severity

Black pine (Pinus nigra J.F. Arnold) is one of the most important reforestation species for dry and rocky terrain in the sub-Mediterranean zone. Fire is an important factor in black pine stands that largely defines the distribution range of black pine and the floristic composition of its stands. Fire causes less damage during autumn or early spring when tree cones contain ripe seeds that can partially reforest burnt surfaces. Every fire is a potentially significant threat to forest habitats. There are many damages, from direct damages to wood mass and reforestation costs, to indirect ecological, edaphic, protective damages and the loss of biological diversity. The aim of prevention works in forestry is to reduce the number of fires and reduce burnt surface area per fire. Research was based on vegetation analysis performed on each experimental plot in a black pine stand. The assessment of fire severity was performed using the Canadian Forest Fire Weather Index (FWI). The assessment of the severity of fire indicates the suitability of conditions for the occurrence of forest fires, and enables sound and effective protective methods beginning with silvicultural works. The results indicate better quality stands in the higher parts of the sub-Mediterranean area. Taking into account the climatic parameter, the areas on the border with the continental climate have better habitat conditions for black pine. Also, attention should be focused on 2012 and 2015. High values (Figure 13 – 16.22, Figure 11 – 6.99, Figure 8 – 8.38, Figure 7 – 12.02 and 12.25, Figure 5 – 8.32) indicate the overlapping of extremely dry periods and extremely high summer temperatures, and probably a strong wind influence that further increases the index. Fire severity assessments indicate the suitability of conditions for the onset of fire

Growth and Development Dynamics of Young Holm Oak (Quercus Ilex L.) Stands after Shelterwood Cutting in Open Forest Road Conditions

The Mediterranean forest region has been exposed to anthropogenic impacts for centuries, and the constant biotic and abiotic factors, together with increasing climate change, have hindered the proper management of forest ecosystems. This study presents the results of multiyear, systematic, specific and practical monitoring of the conversion of holm oak coppices using the principles of the shelterwood system. It also presents the growth and development dynamics of the stand on a permanent experimental plot from 1997 to 2017. The research was performed in the Eumediterranean vegetation zone of coniferous forest (Forest Management, Buzet branch, Pula Forestry Office, Magran Cuf management unit, compartment 83a). The plot has all the properties of a holm oak and manna ash forests (Orno-Quercetum ilicis H-ić/1956/1958). The basic elements of stand structure were monitored: diameter at breast height (DBH), tree height, horizontal crown projection, crown ground shading (light) and the appearance and abundance of all woody vegetation, with special emphasis on the growth and development of young generations of holm oak from seed. The paper also describes the threats limiting growth, development and survival of holm oak from seed (strong shooting tendencies of coppiced holm oak and bay laurel trees, excessive presence of shrubs). Forest management requires effective, timely and repeated tending to thin stands (already under the canopy), while also protecting young trees from wild game. The statistical method of interpolation determined the trends of stand development; trend equation with coefficient of determination (R2) is very high. This indicates the growth and development of the stand in the direction of renewal of holm oak stands. Shelterwood cutting, with regular and timely tending of young generations of trees through a seven-year regeneration period, resulted in a high quality young high forest of holm oak, the first of its kind in the broader Mediterranean area. The indigenous stands of holm oak, as the fundamental climatogenic coniferous species of the Mediterranean species, have multiple roles such as protection from erosion, resilience to biotic and abiotic factors and forest fires, tourism and landscape functions, and other general forest functions, and therefore deserve intensive and ongoing research. Holm oak stands also play a part in conserving genetic and biological diversity, the potential and persistence of forest ecosystems, improving stand structure, stability and resilience of forest ecosystems to climate change, and in the long-term increase the commercial value of forest stands in the Croatian Mediterranean

Impact of the Prudinec/Jakuševec Landfill on Environment Pollution

Neuređena odlagališta otpada osnovni su problem zaštite okoliša u Hrvatskoj. U svezi navedenim, komunalni otpad i odlagališta kao Jakuševec prestavljaju za pojedine gradove iznimno velike troškove. Njihov utjecaj na okoliš je nepovoljan jer uzrokuje zagađenje voda, tla i zraka uz stalnu opasnost za zdravlje ljudi. Početak rješavanja problema započinje sanacijom neuređenih odlagališta otpada. Nakon toga potreban je zaokret u odnosu prema otpadu. Uspostava cjelovitog sustava gospodarenja otpadom sastavni je doprinos svih zakonskih mjera i propisa. U tom sustavu smanjuje se otpad i povećava uporaba, što donosi materijalnu i energetsku korist. Na razini grada Zagreba i cijele države, u današnjim okolnostima provedba sustava daje višestruku korist u ekološkom i gospodarskom pogledu. U radu je dan prikaz odlagališta otpada Jakuševec, koje je složeni difuzni izvor onečišćenja i veliki je problem u pogledu mogućeg štetnog utjecaja na sve elemente okoliša, te je sanacija svakako bila neophodna. Zaštita podzemnih voda i zaštita zraka glavni su razlozi za uređenje odlagališta. Odlagalište otpada Jakuševec-Prudinec služilo je kao odlagalište komunalnog, neopasnog i industrijskog otpada Grada Zagreba i njegove okolice. Nekontrolirano odlaganje otpada na području današnjeg odlagališta otpada započelo je 1965. godine, a 1995. godine prostor odlagališta zauzima 80 ha. U tom je razdoblju neprimjereno odloženo 4,5 milijuna m3otpada, a do 2000. godine volumen odloženog otpada iznosio je 8 milijuna m3. Sanacija neuređene deponije otpada u uređeno sanitarno odlagalište završena je krajem 2003. godine. Odlagalište Jakuševec-Prudinec je od 1965. godine do početka devedesetih godina prošloga stoljeća zauzelo i zagadilo gotovo milijun m3tla (zemljanog materijala) i ozbiljno ugrozilo kakvoću pitke podzemne vode. Ovim istraživanjem prikazan je utjecaj odlagališta na podzemne vode te postupno širenje zagađenja prema istoku, što je potvrđeno pomicanjem granične linije zagađenja od Jakuševca prema Mičevcu, osobito u vrijeme promjenjivih hidrodinamičkih uvjeta u vodonosnom sloju. U radu su prikazani rezultati istraživanja uzročno-posljedične veze između odlagališta otpada Jakuševec i zagađenja podzemne vode (vidi slike 1–5). Sastav organskih zagađivala na odlagalištu Jakuševec upućuje na to da je ondje uz komunalni otpad, odlagan i otpad industrijskog podrijetla, koji sadržava brojne antropogene spojeve koji mogu nepovoljno utjecati na kakvoću podzemne vode. Stoga je nužno stalno praćenje dominantnih antropogenih spojeva u deponiranom otpadu i procjednim vodama.Unmanaged landfills are the basic problem of environment protection on Croatia. Municipal waste and landfills such as Jakuševac incur exceptionally high costs for many towns. Their impact on the environment is highly unfavourable since they pollute water, soil and air and represent a constant threat to human health. The solution to the problem begins with remediation of unmanaged landfills. To launch a remediation programme it is necessary to adopt a new attitude to waste management. The establishment of an integral waste management system is a constituent part of all legal measures and regulations. Such a system ensures the reduction of waste and increased recycling, which provides material and energetic benefits. In today’s circumstances, the implementation of the system at the level of the City of Zagreb and Croatia as a whole results in multiple benefits from both the ecological and economic aspect. The paper gives a survey of the Jakuševac landfill, a complex diffuse source of contamination which causes problems in the sense of possible harmful effect on all environmental elements. Consequently, its remediation was highly expedient. The main reasons for landfill remediation were the protection of groundwater and air. The Jakuševac-Prudinec landfill used to be a disposal site for municipal, non-hazardous and industrial waste of the City of Zagreb and its surroundings. Uncontrolled disposal of waste in the area of the current landfill began in 1965. In 1995, the size of the landfill reached 80 ha. In this period, 4.5 million m3 of waste was disposed inadequately. By the year 2000, the volume of the disposed waste had reached 8 million m3. The transformation of the unmanaged waste disposal site into a managed sanitary landfill was completed at the end of 2003. In the period from 1965 to the beginning of the 1990s, almost one million m3 of soil (soil material) in the Jakuševac-Prudinec landfill was contaminated, and the quality of drinking groundwater was seriously threatened. This research discusses the impact of the landfill on groundwater and the gradual spread of pollution eastwards, as confirmed by the shifting of the boundary pollution line from Jakuševac towards Mičevac, especially during changeable hydrodynamic conditions in the aquifer layer. The paper presents the results of research into the cause and effect relationship between the Jakuševac landfill and groundwater pollution (see Figures 1–5). The composition of organic pollutants in the Jakuševac landfill indicates that this was a disposal site not only for municipal waste but also for waste of industrial origin which contains numerous anthropogenic compounds that might have an adverse effect on groundwater quality. Permanent monitoring of dominant anthropogenic compounds in the disposed waste and leachate is necessary

Ecological Valorisation of the ProtectedArea of “Kopački Rit” Nature Park

Uvažavajući specifičnosti i različitosti, park prirode Kopački rit predstavlja jedno od najznačajnijih područja na istoku Hrvatske, s nizom iznimnih ekoloških sustava. Prema Nacionalnoj klasifikaciji i karti staništa Republike Hrvatske, na području parka prirode nalazi se 25 tipova staništa, a među njima je pet ugroženo na europskoj razini i zaštićeno Direktivom o staništima. Park prirode Kopački rit vrijedna je prirodna baština i u međunarodnim okvirima, stoga se nalazi i na Ramsarskom popisu. Poplavno stanište Kopačkog rita bitno je radi cjelovitosti i raznovrsnosti kopnenih i vodenih ekoloških sustava. U radu se ukazuje na potrebu ekološke i prostorne valorizacije zaštićenog područja, kao instrumenta u razlikovanju primarne i sekundarne zaštite. Prostorna analiza parka prirode Kopački rit izrađena je na podlozi postojećeg prostornog plana (2006) toga područja. Korištene su komparativne metode i metode analize i sinteze. Primijenjena je kvalitativna analitička metoda sa stupnjevanjem elemenata u okviru četiri polja analize (SWOT analiza). Strukturna analiza prostora (slika 1) napravljena je prema Lynch-u (1972). U rezultatima je analiziran i utjecaj različitih gospodarskih djelatnosti na biološku i krajobraznu raznolikost. U zoniranju na temelju plana upravljanja, definirane su glavne zone i određene podzone (slika 2). U njima je dan opis samih zona uz navođenje kriterija zonacije i ciljeva upravljanja. Na taj način određuje se razlika između zona stroge zaštite i aktivne zaštite. Cilj upravljanja je omogućavanje održivog načina korištenja poplavnih dolina, posjeta, rekreativnog ribolova, lovstva, šumarstva i poljoprivrede unutar parka prirode.With its specific features, high diversity, and a multitude of exceptional ecological systems, the nature park of Kopački Rit is one of the most important areas in the east of Croatia. According to the National Habitat Classification and Map of the Republic of Croatia, there are 25 habitat types in the area of the nature park. Five of these are endangered at the European level and protected by the Habitats Directive. Kopački Rit Nature Park has been included on the Ramsar list as valuable natural heritage within the international framework. The floodplain area of Kopački Rit is essential due to the coherence and diversity of terrestrial and aquatic ecological systems. The paper addresses the need for ecological and spatial valorisation of the protected area as an instrument for discriminating between primary and secondary protection. Kopački Rit is a floodplain area resulting from the activity of two large rivers: the Danube and the Drava. Spatial analysis of Kopački Rit Nature Park was made on the basis of the existing spatial plan (2006) of the area. Comparative methods, as well as the analysis and synthesis method were used for the process. A qualitative analytical method with element gradation within four analysis fields was used – strengths, weaknesses, opportunities and threats (SWOT analysis). A structural area analysis (Figure 1) was made according to Lynch (1972). The effect of the activities on biological and landscape diversity was analyzed in the results. The analysis included the effects of forestry, water management, agriculture, game management, traffic, and war events (Table 1 and 2). Based on the management plan, zonation was performed by defining the main zones and determining the sub-zones (Figure 2). The zones were described and the zonation criteria and management goals were provided. In doing so, the difference between the zones of strict protection and active protection was accentuated. The goal of management is to ensure a sustainable use of floodplain valleys and allow visits, recreational fishing, hunting, forestry and agriculture. In order to improve habitat quality, use of the area should be limited by management measures. Ecological and spatial analyses of the protected nature park area were used to determine the difference between individual units within Kopački Rit. Special zones of the basic phenomenon were highlighted, which coincides with the zoning concept within the nature park. In this sense, primary and secondary protection was discriminated

Analysis of the Fire Season of 2020 in the Mediterranean Bioclimatic Zone of Croatian Adriatic

Fire season in the Mediterranean bioclimatic area is most associated with the period from June to late October. Despite this, a large number of fires occur in February and March due to the intentional burning of agricultural lands. A characteristic of the Mediterranean region is the strong adaptation of vegetation to fire, though this adaptation also depends on the frequency and intensity of fires. This frequency is shown on satellite images via MODIS. This paper provides an overview of indicators of vegetation fires in the Croatian coast and karst coastal belt in the 2020 fire season. The 2020 fire season was above average in comparison with the period 2010 to 2019, with more fires than average and more burnt area. A specificity of the 2020 season is seen in the large number of fires in February and March. Fire protection in Croatia is facilitated by the use of new remote sensing technologies, in combination with the existing surveillance and monitoring methods, and organised protection systems to prevent open fires

Contribution to the knowledge of natural regeneration after fires and issues care of burnt areas in the stands of Aleppo pine (Pinus halepensis Mill.)

Rad ukazuje na problematiku prirodne obnove opožarenih površina u sastojini alepskog bora (Pinus halepensis Mill.) na trajnoj pokusnoj plohi postavljenoj u šumariji Šibenik. Tijekom petogodišnjih sukcesivnih izmjera (2001.-2005.) praćen je tijek rasta i razvoja vegetacije po vrstama, brojnosti i visinsko-starosnim klasama. Broj biljaka alepskog bora ukazuje na uspješnu, izrazito obilnu prirodnu obnovu, ali i problem izostanka autohtone vegetacije na opožarenim površinama. Izmjerenih 106.000-121.000 biljaka po ha pokazuje kako su mlade biljke alepskog bora brojnošću, visinom većom i od 2,5m prerasle izgoreni materijal i u potpunosti prekrile opožarenu površinu. Poseban dio istraživanja odnosi se na učinke radova njege i sanacije nakon požara koji je istraživan na tri trajne pokusne plohe na području šumarije Šibenik, Split i Korčula. Istraživanje ukazuje na promjenu pristupa sanacije opožarenih površina izostavljanjem nepotrebnog, mukotrpnog, ali i skupog slaganja preostalog opožarenog materijala na pruge. Tako visoko složen materijal na zraku se, u uvjetima mediteranske klime, izrazito sporo razgrađuje i dugo godina svojom masom povećava ionako stalno prisutnu opasnost od požara te narušava izgled krajolika. Preporuča se sanacija njegom i usitnjavanjem izgorenog materijala po površini motornom pilom tako da je preostali materijal što više uz tlo. Vlaga iz tla i uvjeti mikroklime mlade sastojine alepskoga bora, u kojima će se tako obrađeni materijal naći, pridonijet će bržem razvoju mikroorganizama, njegovoj razgradnji te bržoj humifikaciji. Alepski bor, kao vrsta drveća Eumediterana, ima značajnu i nezamjenjivu pionirsku ulogu u ozelenjavanju opustošenih površina, ali i u pripremi stanišnih uvjeta za dolazak autohtone vegetacije posebice hrasta crnike kao temeljne vrste ovoga područja.This paper points to problems of natural reforestation of burnt areas in the stand of Aleppo pine (Pinus halepensis Mill.) On a permanent sample plot set in the Forest Office Sibenik. Over the successive five-year survey (2001 to 2005.) Was monitored during growth and development of vegetation by type, number and height-age classes. Number of plants of Aleppo pine indicates a successful, highly abundant natural regeneration, but the problem is the lack of native vegetation in areas affected by fire. Measured 106000-121000 plants per ha shows that young plants of Aleppo pine abundance, height and 2.5 m over the burned material is grown and fully covered the burned area. A special part of the research concerns the effects of treatment and rehabilitation work after the fire was investigated at three permanent sample plots in the field of forestry Sibenik, Split and Korcula. Research indicates a change in approach to rehabilitation of the burnt areas by omitting unnecessary, tedious, and costly stacking the remaining burnt material on the track. This highly complex material in air, in the Mediterranean climate conditions, very slowly breaks down and the long years of its mass increases the already ever present danger of fire, and distorts the landscape. It is recommended that rehabilitation care and fragmentation of material combusted on the surface of a chainsaw so that the remaining material to the soil as much as possible. Moisture from the soil and microclimate conditions of young stands of Aleppo pine, which will be processed by the material found, will contribute to the rapid development of microorganisms, its faster degradation and humification. Aleppo pine, a species of Eumediterranean, has a significant and irreplaceable pioneering role in greening the devastated area, but also in terms of site preparation for the arrival of indigenous vegetation, especially the oak as the basic types of this area

Contribution to the knowledge of the moisture content parameters of live (LFMC) and dead (DFMC) forest fuel of strawberry tree (Viburnum tinus L.)

Klimatski parametri imaju velik utjecaj na požare. Najznačajniji klimatski čimbenici koji se uzimaju u obzir kad su u pitanju šumski požari su temperatura i vlaga, odnosno voda (oborine). Sadržaj vlage živog goriva (LFMC) i mrtvog goriva (DFMC) su složeni fenomeni koji se međusobno razlikuju kod pojedine vrste drveća. Promjene u sadržaju vlage su povezane s atmosferskim prilikama i dostupnoj vlagi u tlu s jedne strane te ekofizikalnim karakteristikama vrste s druge strane. Rezultatima ovih istraživanja utvrđene su točne vrijednosti sadržaja vlage živog i mrtvog goriva lemprike (Viburnum tinus L.). Oni bi trebali pomoći kao smjernice u što boljoj protupožarnoj politici, a na korist potrajnog gospodarenja i očuvanja općekorisnih funkcija šuma.In recent years, there has been an increase in the number of forest fires and burned areas in the wider Mediterranean area, including our country. The increased danger is present in all areas affected by the Mediterranean climate. Climatic parameters have a great impact on fires. The most important climatic factors that are taken into account when it comes to forest fires are temperature and humidity or water (precipitation). The moisture content of live (LFMC) and dead fuel (DFMC) are complex phenomena that differ among tree species. Changes in moisture content are related to atmospheric conditions and available soil moisture on the one hand, and the eco-physical characteristics of the species on the other. The results of these researches determined the exact values of live and dead fuel moisture content in the strawberry tree (Viburnum tinus L.). They should help as guidelines in the best possible fire policy, and in favour of sustainable management and preservation of public forest functions. Taking into account the influence of the researched meteorological factors on the live fuel moisture content and the dead fuel moisture content, it can be concluded from the obtained results that the researched meteorological factors have an impact on the dead fuel moisture content, while there was no such impact on the live fuel moisture content

Contribution to the knowledge of the moisture content parameters of live (LFMC) and dead (DFMC) forest fuel of strawberry tree (Viburnum tinus L.)

Klimatski parametri imaju velik utjecaj na požare. Najznačajniji klimatski čimbenici koji se uzimaju u obzir kad su u pitanju šumski požari su temperatura i vlaga, odnosno voda (oborine). Sadržaj vlage živog goriva (LFMC) i mrtvog goriva (DFMC) su složeni fenomeni koji se međusobno razlikuju kod pojedine vrste drveća. Promjene u sadržaju vlage su povezane s atmosferskim prilikama i dostupnoj vlagi u tlu s jedne strane te ekofizikalnim karakteristikama vrste s druge strane. Rezultatima ovih istraživanja utvrđene su točne vrijednosti sadržaja vlage živog i mrtvog goriva lemprike (Viburnum tinus L.). Oni bi trebali pomoći kao smjernice u što boljoj protupožarnoj politici, a na korist potrajnog gospodarenja i očuvanja općekorisnih funkcija šuma.In recent years, there has been an increase in the number of forest fires and burned areas in the wider Mediterranean area, including our country. The increased danger is present in all areas affected by the Mediterranean climate. Climatic parameters have a great impact on fires. The most important climatic factors that are taken into account when it comes to forest fires are temperature and humidity or water (precipitation). The moisture content of live (LFMC) and dead fuel (DFMC) are complex phenomena that differ among tree species. Changes in moisture content are related to atmospheric conditions and available soil moisture on the one hand, and the eco-physical characteristics of the species on the other. The results of these researches determined the exact values of live and dead fuel moisture content in the strawberry tree (Viburnum tinus L.). They should help as guidelines in the best possible fire policy, and in favour of sustainable management and preservation of public forest functions. Taking into account the influence of the researched meteorological factors on the live fuel moisture content and the dead fuel moisture content, it can be concluded from the obtained results that the researched meteorological factors have an impact on the dead fuel moisture content, while there was no such impact on the live fuel moisture content

Growth dynamics of crown shapes in stands of pedunculate oak and common hornbeam

Background and Purpose: Structure of crowns in forest stands is one of the main factors which determines growth and development of trees. Dynamic change occurs with the age of the stand due to silvicultural interventions or natural disturbances duringwhich trees are removed fromthe stand. The aim of this article is to analyse the structure of the crown shape of pedunculate oak and common hornbean trees with regard to diameter at breast height (DBH) and the age of the stand in one of the most important forest community in Croatia. Materials andMethods: The investigation is based on data collected on 47 permanent experimental plotswhichwere established as a chronosequence in a natural range of forests of pedunculate oak and common hornbeam in Croatia. The total surface of all plots amounts to 33.45 ha. Breast height diameter, tree height and stem height were measured on the trees in the experimental plots, and a detailed ground plan was made of horizontal crown projections, from which the crown diameters were calculated. In total 1505 pedunculate oak trees and 2026 common hornbeam trees were measured. For each tree the crown shape was calculated and trees were then grouped in age classes of 20 years, and the shape of the crown analysed according to species and age classes. Correlation between crown shapes and diameter at breast height was investigated for stands of the sixth age class (101 – 120 years) for each species by means of linear regression. Results and Discussion: The shape of the crown of pedunculate oak, although it shows a trend toward growth in relation to diameter at breast height, the regularity pattern of the shape indicates weak character (r=0.441), i.e. variability is explained with only 19%. Crown shapes of common hornbeam are almost constant in relation to diameter at breast height (r=114), and correlation between the examined values cannot be equated by any rational analytical term. Investigation of growth dynamics of crown shape structure was carried out according to the species of trees and age classes, and the interval inwhich 68%(x ± 1.0 s) and 95%of data (x ± 1.96 s)were included. Conclusions: The results of the investigation indicate that dependence on crown shape and diameter at breast height of pendunculate oak and common hornbeam cannot be described by any rational analytical term. Average values of the crown shapes according to age classes can be used as form factors for calculation of crown volume.Data are applicable in various applications, such as for example their integration in a simulator of growth and development of forest stands and examination of the effect of different silvicultural scenario