|The construction of the Danube – Sava canal and the EU Green transition
The plan to construct the Danube - Sava Canal (source: Glas Slavonije) has recently been put back on the agenda. The topic was discussed at the last session of the Council for Slavonia, Baranja and Srijem, at which occasion Mr Galić, the District Prefect, favoured the construction as a Croatian strategic project. However, the City of Vukovar as well as the forestry profession have an opposite opinion. We maintain that the project is not in public interest; rather, it is in the interest of private capital supported by the construction lobby, which wants to make profit on the construction and the subsequent maintenance of the Canal. The topic of the Canal had not been discussed since June 2018, when, after a lengthy discussion, the Assembly of the Vukovar-Srijem County omitted it from the Developmental Strategy.
Several conferences have been held on the topic of the Danube - Sava Canal in recent years. Here are some facts: the planned route of the Canal is 61.4 km from the River Danube at Vukovar to the River Sava at Šamac and is divided into four separate sections: the Danube region, the Nuštar Microelevation, the Central Part and the Sava Region. The width of the Canal is 34 m, the water face is 58 m and the water depth is 4 m. The following will have to be constructed: two docks (Vinkovci and Cerna), two pumping stations, four dams, two derivation canals, one siphon, four railway bridges, seventeen road bridges, one footbridge (Cerna), nine crossings of the canal route with pipelines (oil pipeline, gas pipeline, water supply, sewerage, telecommunications), sixteen crossings with transmission lines of different voltages.
Within the discussion of the canal, it was pointed out among other things that in relation to the space, the construction of the canal was only presented for the houses on the route itself. However, almost as many houses will have to be removed from the contact zone as from the actual canal zone (96 houses by the canal itself and 88 houses in the contact zone). This shows that interventions in the landscape and the settlements will not be restricted only to the construction of the Danube - Sava Canal, but “through massive additional measures will extend outside the Canal zone and probably far beyond (planned drainage and irrigation)”. Thus, it can be assumed that other parts of the landscape in the populated area, such as forests and agricultural land, will also be affected. Yet, there is no mention of this in the spatial plan at all.
Ever since the first mention of the possible construction of the canal, the Croatian Forestry Association has opposed this project due to its detrimental impact on the forest ecosystem, and in particular on the Spačva Forest, the largest forest of pedunculate oak in Europe. We have pointed out again and again that the digging of the canal will disrupt the groundwater regime on which the forests in the Spačva and Bosut basin depend and which are closely linked to the global climate change. In order to obtain reliable results in this area of research, certain time series or actual measurements are required in the present period of the observed climate changes. “As these forests depend on hydrogeological circumstances in the rivers and on their dynamic water regimes, the spatial plan must clearly state the overall interrelated forest ecosystem and its relationship with the water. The selected linear clip of 10,600 ha is not sufficient for the illustration and does not correspond to ecological circumstances”. In addition, the supply of potable water (Regional groundwater supply of «Gundinci - Babina Greda») should also be treated as particularly valuable for protection. “The Canal jeopardizes this strategically important drinking water supply, including its extensive spatial area, without providing accurate data”. It is more ecologically justified and cost efficient to solve the problem of irrigating agricultural areas with gravity from the reservoirs on Psunj and Papuk. F12
Many of the questions related to the project have remained unanswered, in particular those of how the construction of the Canal will affect the contact zones outside the project. Experts wonder whether the construction of the Canal is at all purposeful and possible and what economic importance it will have for Croatia, because “1) Croatia already has a favourable position in international river shipping transport (Vukovar) and 2), the construction of the Canal would encourage competition through Bosnian ports on the River Sava. A cost-benefit analysis is needed prior to determining the plan. Experts are also asking why Croatia should spend 600 million Euro to connect foreign ports along the Danube and thus create competition for itself. Is not it better to run the railway directly from Vukovar to Zagreb, Rijeka or Ploče, rather than first ship to Bosanski Šamac or Brčko, and then continue from there by railway?” What we are most interested in is what will happen to Croatia’s most valuable lowland forests when the level of groundwater, their basic hydrologic factor, drops. Forestry experts express uniform opinion that the forests of the Spačva basin, for example, especially the older ones (therefore, the best quality ones), will dry, because the root system of pedunculate oak will not be able to reach the new groundwater levels.
Therefore, the “new tales” of the Danube - Sava Canal are an invitation to re-engage in well argued debates aimed at protecting our most valuable lowland forests. This is the basic problem compatible with the newly adopted UN Green Transition, which was recently incorporated in the National Development Strategy.
|IZVORNI ZNANSTVENI ČLANCI
|Igor Poljak, Joso Vukelić, Antonio Vidaković, Marijan Vuković, Marilena Idžojtić
| UDK 630* 164 +165 (001)
|Variability of the populations of scots pine (Pinus sylvestris L.) in the northwestern part of Mala Kapela according to the morphological characteristics of the needles and cones
The paper explores the morphological variability of the Scots pine populations in the northwestern part of Mala Kapela. The diversity and structure of the populations were established based on the ten measured morphological characteristics of the needles and cones, using descriptive and multivariate statistical methods. The conducted research established low variability of the morphological characteristics, and the differences between the trees both within and between populations were confirmed for the majority of the studied characteristics. Intrapopulation variability was greater than the interpopulation one, except for the characteristics of needle width, cone length and apophysis width. The research has also confirmed a population variation trend following the ecological principle, as well as a specific gradient, i.e. change in morphological variability related to the change in altitude. Populations from lower altitudes had smaller cones as compared to the populations from higher altitudes. In addition, the pioneering nature of the Scots pine, in which sometimes a very small number of specimens participates in the establishment of new populations, has resulted in low variability of populations and their great differentiation in such a small area.
Key words: conifers; Scots pine; morphometric analysis; intrapopulation variability; interpopulation variability; genetic drift
VUKELIĆ, Joso ŠL
IDŽOJTIĆ, Marilena ŠL
|Mario Slatki, Jelena Kralj
| UDK 630* 148.2 + 653 (001)
|Habitat selection of secondary hole-nesting birds in riverine forests along Drava river in Croatia
The correlation between secondary hole-nesters community characteristics and floristic and structural characteristics of their habitat was studied in riverine forest stands near river Drava in Croatia. Standard point count method was used for bird community sampling and circular plot method for habitat sampling. Sampling was carried out on 66 points. PCA analysis that included 28 independent habitat variables was used, followed by Spearman rank correlation between principal component scores and bird community variables (number of species and number of pairs). Tree basal area was used as an indication of stand maturity and to classify studied points into four forest types (ash, poplar, alder and mixed). Eight secondary hole-nesting species and 14 tree species were recorded. The average forest age was 59.8 ± 20.5 years, with ash and mixed stands being on average older than alder and poplar stands. Shannon-Wiener index of secondary hole-nesters diversity was highest in stands with dominant ash and was increasing with stand maturity. A significant positive correlation was found between number of bird species as well as number of pairs and older stands with lower number of tree species and lower relative number of poplar and alder. It can be concluded that diversity of secondary hole-nesting bird species as well as their abundance is correlated with structural habitat characteristics and that older stands show greater bird biodiversity and abundance.
Key words: bird community; forest habitat structure; forest age
|Murat Kose, Caglar Ugurlu, Omer Oncul, Fatih Demirci, Ilker Angin
| UDK 630* 164 (001)
|The use of sewage sludge and diatomite as growing medium in scots pine (Pinus sylvestris L.) seedling production and evaluation of its land performance
Although several organic and inorganic substrates are added to growing media for improving its physical and chemical characteristics, the need for search of new materials and/or mixtures that reduces the high-priced peat content in substrates is still interesting. This study evaluated the feasibility of reducing the peat content in substrates by replacing it with different amounts of diatomite and sewage sludge for Scots pine seedling (Pinus sylvestris L.) growth and their land performance. In order to evaluate the feasibility of reducing the peat content in substrates by replacing it with different amounts of diatomite and sewage sludge, an experiment was carried out in a temperature-controlled greenhouse under natural light. To evaluate the land performance of Scots pine seedlings grown in different substrates, a trial was established between the years 2013-2017 in Sarıkamış, Kars (NE Anatolia). Sewage sludge application, due to its high organic matter and macro and micronutrient content, has improved the composition of the rhizosphere, thereby resulting in growth acceleration. As a result of the evaluations made in terms of both seedling morphological characteristics and land performance; the best performance was determined in the 9th (50%P+50%SS) and 3rd (75%SS+25%DE) mixtures.
Key words: Sewage sludge; diatomite; peat; scots pine; morphological properties; land performance
| UDK 630* 969 (001)
|Women in forestry in Bosnia and Herzegovina
In most European countries, there is no current knowledge of the representation and role of women in forestry. According to a study by Lewis (2005), conducted in the US, results in 1981 were 17.5% in technical work and 31.8% in administration, 1991 data indicate that 33.5% in the technical sector and 32.7% in the administration. First degree to a female at the UNSA was awarded back in 1955, while two other females graduated year leter. In 1957 total five females gratuted form the University of Sarajevo. The poll was implemented to understand how many women were part of the Forestry Department and their reasons for choosing forestry as a profession. The sample consisted of 78 respondents, who are employed by the following companies: The Federal Ministry of Agriculture, Bosnia and Herzegovina forests, Central Bosnia Forests LLC Donji Vakuf, Una Sana Forests LLC Bosanska Krupa, Zenica-Doboj Forests LLC Zavidovici, KJP Sarajevo-Forests LLC Sarajevo, Forests of the Republic of Serbian LLC Sokolac. There are 83 full-time employed women with degrees from the Faculty of Forestry in the Federation of BiH and 151 in the Republic of Serbian. Only SBK women are employed by HSE – III forestry profession, indicating that there is no interest in doing this job. 19 women out of the total number of 78 respondents have completed agricultural or forestry education, which is only one quartercomparing with the number of women who have completed some other secondary school. This indicates that forestry as a profession is more attractive to women who have graduated from other high schools, e.g. liberal arts schools or other technical schools. Since 1981, forestry has become more intense for women, out of 522 graduates, 142 are women. In the Federation, nine women hold leadership positions, in the Republic of Serbian 21.
Key words: women; forestry; motivation; economy; education
|A. Pilipović, M. Drekić, S. Stojnić, N. Nikolić, B. Trudić, M. Milović, L. Poljaković-Pajnik, M. Borišev, S. Orlović
| UDK 630* 161 (001)
|Physiological responses of two pedunculate oak (Quercus robur L.) families to combined stress conditions – drought and herbivore attack
Pedunculate oak (Quercus robur L.) is economically and ecologically one of the most important tree species in lowland forests of Southeastern Europe, and it is endangered by numerous biotic and abiotic factors. In this study, we investigated the effect of drought and herbivore attack of gypsy moth (Lymantria dispar L.) on two families of young oak seedlings subjected to the following treatments: drought (D); gypsy moth (GM); both drought and gypsy moth (D+GM) and control (Ø) for a period of 15 days followed by a 7-day recovery period. During both treatment and recovery, physiological parameters - net photosynthesis (A), transpiration (E), stomatal conductance (gs), sub-stomatal CO2 concentration (Ci), water use efficiency (WUE), nitrate reductase activity (NRA) and chlorophyll content (Chl) were measured. Our results showed significant effects of stress factors on physiological processes in oak seedlings which could have potential impact on forest regeneration. Also, differences in the reaction between investigated families indicated the need for breeding and selection of more resistant progenies and provenances of pedunculate oak.
Key words: pedunculate oak; photosynthesis; WUE; SPAD; nitrate reductase activity
|Vladan Popović, Aleksandar Lučić, Ivona Kerkez Janković, Ljubinko Rakonjac, Saša Bogdan
| UDK 630* 164 + 232.3 (001)
|Variations in fruit traits of wild cherry (Prunus aviumL.) provenances in Serbia
Natural wild cherry populations in Serbia are a part of the southern border of this valuable forest tree species distribution range. The survival of these marginal provenances in Serbia as well as in the wider region is threatened by climate change, small population sizes, low competitiveness, etc. Therefore, it is recommended to artificially assist population regeneration while increasing their genetic diversity. Although knowledge of the amount and pattern of the specie’s genetic diversity is a prerequisite for its effective conservation and use, related research in the region is scarce. The main goal of this study was to determine the amount and pattern of phenotypic variability of natural wild cherry populations in Serbia. Possible link between revealed pattern of phenotypic variability and genetic differentiation of the provenances was discussed.
Fruits were collected in nine natural populations. Ten morphological traits of the fruits were measured, and average germination rate of the provenances was assessed. The least variable trait was the fruit width (CV = 6.2%), while the most variable trait was the petiole thickness (CV = 29.4%). Analysis of variance revealed significant among-provenance variation for investigated fruit characteristics (p <0.01; α = 0.05), except for the petiole thickness (p = 0.92). Although variability among provenances was significant, the level of within-population variability was much higher (41.2-52.1%) than among-provenance differentiation (5.3-15.2%). The pattern of among-provenance variation was determined by a correlation analysis between provenance mean values and their climatic-geographical variables, whereby fruit thickness and petiole length proved to be useful diagnostic traits. Mean fruit thickness was significantly and positively correlated with altitude (R = 0.69; p = 0.04), annual precipitation as snow (R = 0.80; p = 0.01), and annual degree-days below 0 °C (R = 0.70); p = 0.04). The average petiole length was significantly and negatively correlated with the annual precipitation as snow (R = -0.69; p = 0.04), while it was positively correlated with annual heat to moisture index (R = 0.71; p = 0.03). The results revealed an ecoclinal pattern of phenotypic differentiation among the provenances due to their habitat’s altitude and other ecological variables closely related to altitude.
Although this study basically dealt with phenotypic variability of wild cherry fruits originating from natural populations, the results indicate likelihood for genetic differentiation of the provenances due to altitude. This likelihood provides the basis for recommending vertical seed zonation, as well as congruent use of reproductive material for assisted restoration of wild cherry populations in Serbia. However, to confirm this presumption of ecoclinal pattern of genetic differentiation, it is necessary to conduct analyses of various phenotypic traits in common garden experiments (e.g. provenance trials) as well as analyses of appropriate DNA markers.
Key words: morphology; seed; phenotypic traits; provenance differentiation; ecocline.
Ivona Kerkez Janković
BOGDAN, Saša ŠL
|Damir Drvodelić, Milan Oršanić, Mirjana Grahovac-Tremski
| UDK 630* 232.3
|Nursery production of forest fruit trees in nurseries of Croatian forests d.o.o.
The article defines the term forest fruit trees or forest fruits that have been present in Croatian forestry for years and compares the term with other terms that are not synonymous and refer to forest trees, shrubs and ground growth of edible and medicinal fruits, wild fruits and domesticated fruits. Typical species representatives are listed for each term. The production by types of trees in the nurseries of Hrvatske šume d.o.o. is shown. in 2019/2020 years according to Forest Administration (FD), organizational units and nurseries. Regarding the production of forest fruit trees, edible and medicinal fruit trees, wild fruits and domesticated fruits, it is present in only three nurseries of Hrvatske šume d.o.o. (Zelendvor, Oštarije and Lukavec). In these three nurseries, a total of only four species from the above four categories are produced (2019/2020): service tree, wild cherry, sweet chestnut and black walnut. All four species are produced in the Zelendvor nursery, while in the Oštarije nursery, wild cherry seedlings are also produced, and in the Lukavec nursery only wild cherry seedlings are produced. The production and delivery of planting material of these species from the nursery of Hrvatske šume d.o.o. is shown. for the period 2012 to 2017. In stock or in production, in all nurseries of Hrvatske šume d.o.o. for the period from 2012 to 2018, there were mostly black walnut seedlings in the amount of 183,670 pieces, followed by seedlings of wild cherry with 132,069 pieces, sweet chestnut with 53,010 pieces and wild pear with 4,882 pieces. The most delivered seedlings, according to production, were black walnuts in the amount of 191,435 pieces, followed by wild cherry seedlings with 71,954 pieces, sweet chestnuts with 28,515 pieces and wild pears with 2,860 pieces. In the observed research period (2012-2018) in all nurseries of Hrvatske šume d.o.o. only 4 species from the above categories were produced with a total stock or production of 373,631 pieces of forest seedlings and a delivery of 294,764 pieces. In total, for all four species, it can be seen that 78,867 pieces of seedlings were grown more than delivered. Due to the possibility of organic farming, good adaptability of species to global climate change, providing incentives and not too demanding care, in the near future there will be increasing emphasis on species breeding to obtain secondary or non-timber forest products in plantations. Due to changing climatic conditions and the synergy of a number of unfavorable biotic and abiotic factors, many indigenous species are endangered today and are gradually or abruptly drying up and decaying. Some species of forest fruit trees, forest trees, shrubs and ground growth of edible and medicinal fruits, wild fruits and domesticated fruits will benefit from climate change, which will lead to the expansion of their natural range with increasing potential areas suitable for artificial cultivation.
Key words: nursery production; black walnut; wild cherry; wild pear; service tree
DRVODELIĆ, Damir ŠL
ORŠANIĆ, Milan ŠL
GRAHOVAC - TREMSKI, Mirjana ŠL