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As a basic study for pollen analysis, the production rate of Morus alba (white mulberry) pollen grains in an abandoned M. alba plantation was determined over a three-year period from 1997 to 1999. The number of pollen grains per male catkin was assessed and the fall rate of male catkins was measured using five litter traps. The mean production rate was 2.6 × 10^ grains ha^yr^ (range = 2.2-3.4 × 10^ grains ha^yr^). This is near the lower end of the range of pollen production rates that have been obtained from many other tree species across several forests., Kiel fundamenta studado por polen-analizo, polenera produktaĵo por jaro de morsarbo, Morus alba en forlasita M. alba plantejo estis determinita dum tri-jara periodo de 1997 ĝis 1999. La nombro de poleneroj por vira infloresko estis esplorita, kai la defalonombro por jaro de vira infloreskoj estis mezrita, uzante kvin rubajn kaptilojn, t.e. sakojn por ricevi defalintajn infloreskojn. La meza produktaĵ-rilatumo de poleneroj estis 2.6 × 10^ eroj hektaro^ jaro^ (amplekso estis 2.2-3.4 × 10^ eroj hektaro^ jaro^). Ĉi tiu estas apud malalta fino de amplekso de polena produktaĵo, kio estis akirita por multaj aliaj arbospecioj el kelkaj arbaroj.

Data from long-term (30 yrs) monitoring of changes in the ecological conditions and species composition of all vegetation layers (tree stand, young growth, undergrowth, dwarf shrub-herb layer, moss layer) of a drained herb-sphagnum pine stand after a combination of treatments (removal of birch + mineral fertilization) are reported. Owing to improved light and nutrient supply, representatives of oligotrophic bogs and a majority of plants associated with mesotrophic and eutrophic mires almost disappeared from the dwarf shrub-herb layer, while the previously absent mesotrophic forest-dwelling species arrived. The progressively thick herb layer has substantially influenced the distribution of nutrients. The rapidly and fully decomposing herbaceous dieback promoted the activity of microbiological processes, and biological recycling of nutrients from fertilizers provided for a long-lasting increase in the stand productivity. The moss layer lost the edifier species of oligotrophic bogs at the same time with increased representation of the forest flora and arrival of new species (Polytrichum commune, Rhytideadelphus triquetrus). Overall, the species composition of the ground cover settled down 8–10 years after the experiment had begun. Improved moisture and air conditions and nutrition have led to plentiful and rapid growth of spruce saplings. At the same time, the development of a dense ground cover, undergrowth and young birch growth has negatively affected the emergence of pine saplings, their further growth and development. There is no young growth of this species in the site now, and the number of pine trees and its contribution to the main stand are declining. The shares of spruce and birch in the stand are growing proportionately. An especially pronounced increase lately has been in the role of spruce in the stand. Generally speaking, the combination of treatments has transformed the herb-dwarf shrub and moss layers, and notably altered the growth conditions for and composition of young woody growth, facilitating the formation of a highly productive and commercially valuable stand.

V magistrskem delu obravnavamo žledolom, ki je ob koncu januarja in začetku februarja 2014 povzročil gmotno škodo ne le na vegetaciji, temveč tudi na energetski in železniški infrastrukturi. Po dosedanjih ocenah gre za enega izmed najobsežnejših žledolomov na območju Slovenije v zadnjih desetletjih. V raziskavi nas je zanimala prostorska razporeditev sprememb v biomasi bukovih in smrekovih sestojev na z žledom prizadetih območjih, zaznanih s pomočjo satelita Landsat. V raziskavo sta bili zajeti občini Tolmin in Dobrova - Polhov Gradec. Na omenjenih območjih smo primerjali stanje bukovih in smrekovih sestojev pred ledeno ujmo ter po njej. Medtem ko so nam Landsat satelitski posnetki služili kot orodje za determinacijo območij negativnih sprememb v rastlinski biomasi, smo s pomočjo LiDAR podatkov izračunali različne izpeljanke, kot so digitalni model reliefa (DMR), digitalni model krošenj (DMK) in digitalni model površja (DMP). Izračunano gmotno škodo smo finančno ovrednotili na podlagi podatkov povprečnih odkupnih cen lesa, pridobljenih s strani Statističnega urada Republike Slovenije (SURS). Analiza podatkov, izračun izpeljank ter izdelava tematskih kart in grafikonov je potekala s pomočjo programske opreme ArcGIS. In this master’s thesis we examine the problem of the ice storm, which caused material damage not only on vegetation, but also on energy and railway infrastructures. According to previous estimates, this destructive ice storm was one of the most extensive in Slovenia in recent decades. In the study, we examined the spatial dimension of changes in the biomass of beech and spruce forest stands in affected areas, detectable using the Landsat satellite. The study’s research covers municipalities of Tolmin and Dobrova - Polhov Gradec. While the Landsat satellite imagery was used as a tool for determining areas of negative changes in biomass, various variables such as digital elevation model (DEM) and digital surface model (DSM) were calculated by using the LiDAR data. The material damage was financially evaluated according to the national average purchase prices of wood. The data analysis, the calculation of variables, and the production of thematic maps and charts were carried out using the ArcGIS software.

Les études des bois gorgés d’eau découverts sur vingt sites archéologiques localisés à Clermont-Ferrand (Puy-de-Dôme) ont pour objectif de mettre en évidence des pratiques sylvicoles liées aux besoins en bois d’œuvre au cours du développement urbain de la ville d’Augustonemetum durant l’Antiquité. Le croisement des trois disciplines, xylologie, dendrologie et dendrochronologie, est réalisé pour identifier les essences des bois issus des fouilles archéologiques, dater ces derniers quand le nombre de cernes le permet et évaluer la morphologie et l’âge de l’arbre lors de son abattage. Sur cette base, il est possible de percevoir une évolution dans l’approvisionnement en bois et son utilisation, ainsi que dans la composition et la structure des peuplements forestiers exploités. Cette évolution permet de dégager certains traits des pratiques sylvicoles pour ce contexte antique. Studies of waterlogged wood, carried out on twenty ancient archaeological sites located in Clermont-Ferrand (Puy-de-Dôme), have allowed assumption on wood supply: species selection according to timber use (construction, manufacture of objects) and the selection of trees according to age or diameter. These analyses aim to highlight the silvicultural practices in Antiquity in relation with the city Augustonemetum and its timber needs. The crossing of three disciplines (xylology, dendrology and dendrochronology) is performed to identify the wood species from archaeological excavations, dating them when the ring series is enough and to evaluate the morphology and age of the tree when it was felled down. These approaches aim to assess the changes in wood supply and outline their use in order to highlight forestry practices in this antique context.

Pure and strip pine forest plantations were widely practiced in ribbon forests of the Altai Territory by the species mixture of Scots pine (Pinus sylvestris L.) with silver willow (Salix acutifolia Willd.). In the 1990s this approach was cancelled. We can assess the productivity of those plantations so far it is still possible to determine which artificial pine forests were created with preliminary willow planting The paper presents the studies carried out in the Barnaul ribbon forest in the Rubtsovskiy and Uglovskiy districts of the Altai Territory from 2013 to 2016. Forest growth conditions are described by a sharply continental climate, lengthy cold winters and short hot summers; small (250...350 mm/year) amount of precipitation; sandy soils and the level of groundwater, located at a depth of 4 to 10 m and more. In the course of the research, the authors have used the quadrant sampling method. The sample plots (57 pcs.) are established in artificial pine forests of the forest type of dry coniferous forest of flat hilly surfaces. The investigated stands are from 13 to 81 years of age, of II-V quality class and different species mixture patterns Thinning in these stands has not been carried out. The mensurational description of the most typical studied pine forests and yield charts of artificial pine forests with different tree arrangement on the area are also presented. Data approximation is performed using the Terazaki function, since it demonstrates the highest value of the determination coefficient in comparison with the other S-shaped functions. The most productive artificial pine forests are formed from forest cultures with a uniform arrangement of seedlings in the ribbon forests of the Altai Territory. Pine stands created by the strip forest plantation method in the mixture with silver willow (Salix acutifolia) are more productive than stands formed from forest cultures with a similar arrangement of trees on the area but without willow. В ленточных борах Алтайского края наряду с посадкой чистых сосновых лесных культур широко практиковалось их создание кулисным способом в смешении сосны обыкновенной (Pinus sylvestris L.) с ивой остролистной ( Salix acutifolia Willd.). В 90-е гг. XX в. эта практика была прекращена. Целесообразно оценить производительность таких древостоев пока еще можно определить, какие искусственные сосняки создавались с предварительным шелюгованием. Исследования проведены в Барнаульском ленточном бору на территории Рубцовского и Угловского административных районов Алтайского края с 2013 по 2016 г. Лесорастительные условия района: резко континентальный климат, продолжительная холодная зима и короткое жаркое лето; небольшое (250...350 мм/год) количество осадков; песчаные почвы; уровень грунтовых вод, находящийся на глубине от 4 до 10 м и более. В ходе исследований применялся метод пробных площадей. Пробные площади (в количестве 57 шт.) закладывались в искусственных сосняках типа леса сухой бор пологих всхолмлений. Исследуемые древостои имели возраст от 13 до 81 года, класс бонитета II-V и разные схемы смешения пород. Рубки ухода в рассматриваемых насаждениях не проводились. Приведены таксационная характеристика наиболее типичных исследованных сосняков и графики хода роста по запасу искусственных сосняков, имеющих различное размещение деревьев на площади. Аппроксимация данных была выполнена при помощи функции Теразаки, так как она показала наибольшее значение коэффициента детерминации по сравнению с другими S -образными функциями. В ходе исследований установлено, что в ленточных борах Алтайского края из лесных культур с равномерным размещением сеянцев на площади формируются наиболее производительные искусственные сосняки. Если сравнить производительность древостоев, сформировавшихся из лесных культур сосны, созданных кулисным способом в смешении с ивой остролистной, и производительность древостоев, образованных из лесных культур с аналогичным размещением деревьев на площади, но без ивы, то можно сделать вывод, что первые формируются в более производительные древостои.

In forest ecosystems, the specific influence of soil resources on stand productivity is difficult to assess because many other ecological variables also affect tree growth. In this study, we took advantage of a natural soil gradient, from shallow calcic soil to deep acidic soil, all with similar climate, atmospheric depositions, species composition and management, to determine the relationship between soil nutritive resources and the growth and mineral nutrition of a beech ( Fagus sylvatica ) mature forest of Northeastern France. Soil resources were assessed through the quantification of the stocks of available water and mineral nutrients (Ca, Mg, K and P 2 O 5 ). Beech stand growth and mineral nutrition were determined through the use of several indicators, i.e., standing aboveground biomass and annual biomass production, potential growth index (prediction of the height of dominant trees at 100 years) and foliar nutrient content. We observed a gradient of nutritive resources in soils as well as a gradient of stand growth on the study site: the current aboveground biomass was highest on the calci-brunisol which presented the highest water and nutrient stocks while it was lowest on the rendisol, characterized by a very low water holding capacity and a very low stock of available K. However, the growth of beech trees on the rendisol was equivalent to the highest growth classes of beech trees in France, and K nutrition was optimal. Observations on the study site suggest that, in favorable climate conditions, some biological adaptation processes, such as an efficient root colonization as well as an efficient nutrient cycling may allow to maintain stand growth and nutrition on soils with low water and nutrient reserves. The fertility of forest soils has thus to be assessed in a dynamic way by integrating nutrient fluxes as well as the adaptations of trees to environmental constraints. The biological processes become an increasingly important part in the conservation of soil fertility, notably in the perspective of global changes.

Entretenir sa forêt: Fiche technique; Peu de temps après la création de l’IBP en 2008, le CRPF Midi-Pyrénées a proposé cette méthode à un propriétaire tarnais qui réalisait son PSG et souhaitait mieux intégrer la biodiversité ordinaire dans sa gestion courante. C’est ce travail qui est ici relaté. Notons qu’en complément à l’IBP, le propriétaire a utilisé ultérieurement la démarche BIOFIL 1, développée par le CRPF Midi-Pyrénées et permettant notamment de mieux repérer à l’échelle de la forêt leséléments de biodiversité remarquables.

Survival analysis methods make better use of temporal information, accommodate multiple levels of explanatory variables, and are meant to deal with interval-censored data. In a context of harvest modeling, this approach could improve some known limitations. In this study, we used data from a network of permanent plots in the province of Quebec, Canada, as a real-world case study. We tested the potential of survival analysis to predict plot-level harvest probabilities from plot- and regional-level variables. The approach also included random effects to account for spatial correlations.The results showed the potential of survival analysis to provide annual predictions of harvest occurrence. Both regional and time-varying variables, as well as spatial patterns, had important effects on the probability of a plot to be harvested. Respectively, reductions in the annual allowable cut volumes led to a decrease in the harvest probabilities. Greater harvest probabilities were associated with the broadleaved dynamics class and higher values of basal area. In contrast, they were decreased by stem density and slope classes.The spatial random effect resulted in an improvement of the model fit. Our plot- level model improved some limitations reported in previous studies by taking the effect of a time-varying regional variable into account.; Les méthodes d’analyse de survie utilisent mieux l’information temporelle, tiennent compte de multiples niveaux de variables explicatives et sont destinées à traiter des données censurées par intervalle.Dans un contexte de modélisation de la récolte, cette approche pourrait améliorer certaines limites connues. Dans cette étude, nous avons utilisé des données d’un réseau de placettes permanentes de la province de Québec, au Canada, pour servir d’étude de cas concret. Nous avons testé le potentiel de l’analyse de survie pour prédire les probabilités de récolte à l’échelle de la placette, à partir de variables associées à la placette et à la région. L’approche comprenait également des effets aléatoires pour tenir compte des corrélations spatiales.Les résultats ont montré le potentiel de l’analyse de survie pour fournir des prédictions annuelles de l’occurrence de la récolte. Les variables régionales et les variables qui évoluent en fonction du temps, ainsi que la configuration spatiale, avaient des effets importants sur la probabilité qu’une placette soit récoltée. Les réductions de la possibilité annuelle de coupe entraînaient une diminution des probabilités de récolte. Des probabilités de récolte plus grandes étaient associées à la classe de dynamique forestière feuillue et à des valeurs plus élevées de la surface terrière. Inversement, elles étaient diminuées par la densité des tiges et les classes de pente.L’effet aléatoire spatial a entraîné une amélioration de l’ajustement du modèle. Notre modèle à l’échelle de la placette a amélioré certaines limites signalées dans les études précédentes en prenant en compte l’effet d’une variable régionale qui évolue dans le temps.

Key message This data set provides unique empirical data from triplets of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) across Europe. Dendrometric variables are provided for 32 triplets, 96 plots, 7555 trees and 4695 core samples. These data contribute to our understanding of mixed stand dynamics. Dataset access at http://dx.doi.org/10.5061/dryad.8v04m. Associated metadata available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/? uuid=b3e098ca-e681-4910-90990e25d3b4cd52&hl=eng.; Key message :This data set provides unique empirical data from triplets of Scots pine (Pinus sylvestris L.) and European beech (Fagus sylvatica L.) across Europe. Dendrometric variables are provided for 32 triplets, 96 plots, 7555 trees and 4695 core samples.These data contribute to our understanding of mixed stand dynamics.Dataset access at http://dx.doi.org/10.5061/dryad.8v04m.Associated metadata available at https://metadata-afs.nancy.inra.fr/geonetwork/apps/georchestra/? uuid=b3e098ca-e681-4910-90990e25d3b4cd52&hl=eng.

• SPAC model to predict forest water consumption under wet and dry conditions.• Interactions and feedbacks between physical climate and ecological processes.• Control of root water uptake by water diffusion processes between roots and soil.• Key processes involved: xylem hydraulic resistances and stomatal conductance.• Buffering action of capacitive discharge on daily fluctuations of xylem tension.Modelling hydraulic functioning of a forest stand is a prerequisite to predict the future impact of climate change on forests. In this paper, we used a process-based model of the soil-plant-atmosphere continuum to investigate the links between energy budget and water balance, and to emphasize the key processes involved in the control of transpiration and water status of forest trees. The model describes stomatal conductance as a function of photosynthesis, intercellular CO2 concentration and leaf water potential. The latter in turn depends on soil and tree storage water potentials, the water flux through the soil and the trees, hydraulic resistances and stomatal conductance. We have implemented in the model a detailed tree water storage scheme, canopy interception of precipitation, and the rate of change of forest canopy energy storage. In this model, physical climate processes and ecological processes are closely coupled which involves important interactions and feedbacks. The model reproduces the observed variation in leaf water potential in dry and wet conditions. It successfully captures the decrease in soil water content under both non-limiting soil water and severe drought conditions and there is a good agreement between measured and simulated sensible and latent heat fluxes throughout the season. Simulations also show that significant amounts of intercepted water can be lost through evaporation during rain events. The results corroborate that the concept of hydraulic capacitance provides a simple and effective means of simulating the buffering action of tree water storage on tree water status. The two key parameters that control transpiration and water status of the trees are xylem hydraulic resistances and sensitivity of stomata to leaf water potential. The results confirm that stomatal conductance cannot be modelled using leaf-level processes alone, but must be incorporated into a comprehensive model of water flow from soil through the plants to the atmosphere where various self-regulation are set up to ensure a complete water status equilibrium.

In the case study from the basin of the Šance reservoir in the Moravian-Silesian Beskids, we examined the differences in the extent of damage in individual winter seasons and differences in the quantity of snow in individual situations. The intensity of damage to predominantly spruce stands was evaluated as the ratio of the number of individual trees damaged in the particular season to the total number of trees in the study plots. The quantity of snow was measured using quantitative parameters of snow cover. The objective of this paper was to describe model scenarios characterised by the expected intensity of stand damage corresponding to the course of winter expressed in quantitative parameters of snow cover on the base of similar/dissimilar situations. Individual winter seasons were thoroughly described in the results. The output is the description of three model scenarios with different intensities of stand damage that differ in the measured values of snow quantity

The paper analyses the implementation of the growing stock estimation methods in the forests of Slovakia between the years 2001 and 2010. The analysis focuses on mature stands with primary timber production function in more detail. The share of more accurate and costly methods has been continuously decreasing; and since 1993 yield tables have become the most prevalent methods of estimation used in mature stands are. After more than 20 years of their implementation it is important to verify the accuracy of their application, the accuracy of the provided input variables and the methodology behind the growing stock estimation. The paper identifies the cases of their incorrect application, and the risks associated with the quantification of input data, and proposes the measures for their elimination. It stresses the importance of inspection of monitoring the quality of Forest Stewardship Programmes which operates as a specialised task since 2008. Since that time, a positive trend has been observed in mature stands of timber production forests in which mathematical- -statistical sampling methods are gaining on importance.

We use a new modelling approach to predict the cumulative impact of Phytophthora ramorum on the dynamic distribution of tanoak (Notholithocarpus densiflorus) and other tree species in coastal-Californian forest-communities. We explore the effectiveness of disease-management strategies for the conservation of tanoak at stand level. Forest resources are increasingly threatened by emerging pathogens such as P. ramorum, a generalist that kills hosts and has altered ecosystems in the USA and Europe. In coastal California, P. ramorum has the greatest impact on tanoak through leaf sporulation and lethal bole infections, but also sporulates on the common overstory-tree bay laurel (Umbellularia californica) without significant health impact. Such epidemiological differences impede host-species coexistence and challenge pathogen management. For most disease-impacted natural systems, however, empirical evidence is still insufficient to identify effective and affordable pathogen-control measures for retaining at-risk host populations. Yet, landscape-scale tree mortality requires swift actions to mitigate ecological impacts and loss of biodiversity. We apply a mathematical model of the feedback between disease and forest-community dynamics to assess the impacts of P. ramorum invasion on tanoak under stand-scale disease-management strategies by landowners aiming to retain tanoak and slow disease progression: (1) removal of inoculum through reduction of bay laurel abundance, (2) prevention of tanoak infection through chemical protection (acting epidemiologically like a vaccine), and (3) a combination strategy. The model results indicate that: (1) both bay laurel removal and tanoak protection are required to help maintain tanoak populations, (2) treatment effectiveness depends on forest composition and on threshold criteria, (3) sustainable tanoak conservation would require long-term follow-up of preventive treatments, (4) arresting basal sprouting upon tree removal may help to reduce inoculum. These findings suggest potential treatments for specific forest conditions that could be tested and implemented to reduce P. ramorum inoculum and disease and to conserve tanoak at stand level.

The ribbon forest zone of Altai Krai is located in the Kulunda Steppe and on the Priobskoye Plateau. The climate of this region is characterized by extreme aridity. Due to the harsh climate and the importance of the ribbon forests for the environmental sustainability of the region, artificial reforestation is an integral part of the regional forest management. Forest stands of artificial origin currently occupy a large area within the ribbon forest zone, as evidenced by forest inventory data. However, due to the fact that surveys are not conducted simultaneously on the whole territory of Altai Krai, and that they miss some of the forest management units, forest inventory data do not provide an up-to-date assessment of artificial reforestation efforts. Our project attempted to update the existing data of forest resource assessments and evaluate the results of artificial reforestation efforts in the ribbon forest zone of Altai Krai. This article presents data on the distribution of the artificially reforested area by predominant species and type of growing conditions, and the distribution of the growing stock of the artificially established stands by age and type of forest growing conditions.

In this study, shifts from the current forest physiognomy to a target forest physiognomy were modeled by applying the concept of zoning simulation. The objective was to present the process of generating management options for man-made forests in Kanagawa Prefecture, Japan. The assessment method was a wide-ranging and long-term simple simulation based on several indicators, such as geographical distribution and tree species, and adapted the concept of changes in forest physiognomy. A headwater forest in Kanagawa Prefecture, which covers an area of about 3784 ha and consists of 4445 forest stands, was investigated. Four plans were established based on the present state of the forest stands. The results indicated that factors for expressing forest physiognomy and their expression methods should be determined, and physiognomy models should be constructed to establish the actual state of the forests in each region. With this simulation, it is possible to forecast long-term changes at forest stand and basin levels for each scenario. However, only data from forestry register were used in this study, and it is expected that different results would be obtained by conducting a determination of stand position in the forest physiognomy together with a field survey.

Physical, chemical and biological properties of soil are influenced by vegetation types which grow above it. Different tree species of stands will produce difference litter quantity, litter quality and also plants’ root system. Therefore quantifying physical and chemical soil properties in several stands after rehabilitation of degraded land will increase the understanding of forest soil characteristics. The research was conducted in 8 forest stands in Wanagama I, Gunungkidul, Yogyakarta. Collection of soil samples was done at the depth of 0-10, 10-30 and 30-50 cm by making soil profile. The result showed that the textural classes were from sandy clay loam to clay. The content of clay increased with increasing soil depth. Bulk density did not differ much among the profiles and soil depth, ranging from 0.90 to 1.28 g/cm3, and so were particle density ranged from 2.19 to 2.55 g/cm3 and pore space ranged from 47.89 to 58.08 %. pH H2O ranging from 5.81 to 7.49 (slightly acid to neutral), meanwhile pH KCl ranging from 4.44 to 6.37. C-organic content varied widely among the vegetations and soil depth ranged between 0.11 and 5.17 %. Available P and total P varied widely from 1 to 104 ppm and from 20 to 390 ppm, respectively. CEC were not much different among the profiles and soil depths, ranging from 19.80 to 38.06 cmol (+)/kg and base saturation in all samples were very high i.e. > 100 %. ABSTRAK Sifat-sifat fisik, kimia dan biologi tanah dipengaruhi oleh tipe vegetasi yang tumbuh di atasnya. Perbedaan spesies pohon suatu tegakan akan menghasilkan perbedaan jumlah seresah, kualitas seresah dan juga sistem perakaran. Kuantifikasi sifat-sifat fisik dan kimia tanah pada beberapa tegakan hutan pada lahan terdegradasi setelah direhabilitasi akan meningkatkan pemahaman mengenai sifat-sifat tanah hutan. Penelitian dilakukan pada I jenis tegakan hutan di Hutan Pendidikan Wanagama, Gunungkidul, Yogyakarta. Pengambilan sampel tanah dilakukan pada kedalaman 0-10, 10-30 dan 30-50 cm dengan cara membuat profil tanah. Hasil penelitian menunjukkan bahwa kelas tekstur mulai dari geluh lempung pasiran sampai lempung. Kandungan lempung meningkat dengan semakin dalamnya tanah. Berat volume tidak banyak berbeda antar profil dan kedalaman tanah, berkisar antara 0,90 - 1,28 g/cm3, dan kerapatan partikel berkisar antara 2,19 - 2,55 g/ cm3, dan ruang pori tanah berkisar antara 47,89 - 58,08 %. pH H2O berkisar antara 5,81 - 7,49 (agak asam sampai netral), pH KCI berkisar dari 4,44 - 6,37. Kandungan C-organik sangat bervariasi antar jenis vegetasi dan kedalaman tanah mulai 0,11 - 5,17 %. Kandungan P tersedia dan P total sangat bervariasi, secaraberturut-turut dari 1- 104 ppm dan 20 - 370 ppm. Nilai KPK tidak banyak berbeda antar profil dan kedalaman tanah berkisar antara 19,80 - 38,06 cmol (+)/ kg dan kejenuhan basa untuk semua sampel mempunyai nilai sangat tinggi > 100 %.

The central task of this research was to choose the age at which stands of growing timber should be harvested. The choice governs how long each stand must continue to earn interest, and also governs the size of the total inventory that must be maintained to sustain the annual harvest. It is a problem that calls for analysis of biological as well as economic relationships over time, and has intrigued economists for more than two centuries. The paper presents the theoretical background and results of economic optimization of the rotation age of a single stand. It analyses the timber production function depending on rotation age, growth, cost and other characteristics of forest, as well as the costs of land. The prerequisite for achieving the economic optimum of the rotation age of a stand is to balance the current increase in the total timber production value (growth and yield) and the value of opportunity costs from delaying cutting till the next year. This paper demonstrates how this economically optimum rotation age can be calculated, and how it varies according to the biological growth and economic parameters of the forest.

In its upper course the Soča River is one of the best preserved Alpine rivers. Despite that, there have been few studies of its riverine forests, which are an integral part of the river. The research in this thesis encompasses part of the river basin between the towns of Kobarid and the confluence with the Tolminka River. It was found that the riverine forests in the study area are not a homogeneous habitat. Rather, they consist of numerous phytosociological communities with a syn-dynamic connection. The majority of riverine forests in the study area is younger than 50 years old and were established either by the overgrowing of agricultural land or from degraded forests. Accordingly, the forest structure is characterised mainly by uneven-aged stands or younger structural stages, which are frequently returned to their earlier stages due to human impacts. The majority of these forests have low quality prospects. Based on their vegetation and stand characteristics, the riverine forests under study were classified into six stand types. A comparison of the functions and characteristics of particular forest types revealed similarities between the stand types of initial willow, white willow and grey alder. Forests in this cluster are under the influence of soil water and high floodwaters. Their most pronounced function is ecological. In their growing stock, there is a large share of deciduous softwood. Forests in this cluster cover 62% of all riverine forests in the study area. Silvicultural measures are rare in these forests and are less important for the existence of the stands than environmental features like a high level of soil water and minimised human impact on their habitat and the river course. An important characteristic of the second cluster, which consists of pioneer forest on higher-lying river terraces and the riparian corridor stand type is a lack of contact with soil water. In the tree layer of the growing stock in this cluster, species appearing on drier riverine-forest sites prevail (European ash, small-leaved lime, European hornbeam, sessile oak). These forest stands have a greater timber industry potential therefore, modest measures and limited human impact (especially that which leads to a change in land use like forest grazing and clearing) are recommended. The stands in this cluster cover 30% of the analysed riverine forest area. The third cluster of riverine forests consists of anthropogenic riverine forest stands where the human impact is so significant that they mainly perform a social function. The stand type of this cluster represents 8% of the riverine forests in the study area, and it is suggested that they should be managed as parkland and not as forest areas. Directing visitors to these areas would unburden other, more preserved stand types from the pressures created by human activities (tourism, recreation, construction work). Growth and increment analyses of the most common tree species in the riverine forests in the study area show that mainly olive and white willow, followed by grey alder, have substantial current height (both willow types up to 1.14 m/year), diametric (willow up to 1.4 cm/year) and volumetric increments. However, their rapid growth makes these subjects prone to rapid ageing. The region of northern Primorska was inhabited early in history. Accordingly, there was great pressure imposed on riverine forests already in the past. The analysis of old maps revealed that up to the beginning of the 20th century, the riverine forest area within the scope of analysis was under 50 ha. Within the process of the overgrowing of agricultural land in Slovenia, a process that is currently still underway, the aforementioned riverine forest area increased to 229.16 ha. This thesis shows that the study area is not an unspoiled wilderness. On contrary, just as in the past, it is a crossroads of numerous and frequently conflicting interests. The riverine forest situation on the Soča River in the area b Soča je v zgornjem toka do sotočja z reko Tolminko, ena izmed najbolje ohranjenih alpskih rek. Kljub temu je bilo v preteklosti narejenih zelo malo celovitih raziskav gozdov obrežnega pasu, ki so z reko neločljivo povezani. V našo raziskavo smo vključili del porečja med Kobaridom in Tolminom. Ugotovili smo, da obrečni gozdovi preučevanega območja niso homogeno rastišče. Sestavlja jih več fitocenoloških združb, ki so sindinamsko povezane. Velika večina obrečnih gozdov preučevanega področja je mlajša od 50 let in je nastala z zaraščanjem kmetijskih površin ali iz degradiranih gozdov. Posledica tega je med drugim tudi struktura gozdov, saj prevladujejo raznomerni gozdovi ali mlajši razvojni stadiji, te pa človek s svojimi posegi pogosto vrača v začetne razvojne faze. Z redkimi izjemami je tudi zasnova gozdov slaba. Glede na vegetacijske in sestojne lastnosti smo obrečne gozdove preučevanega območja razdelili na šest sestojnih tipov. Primerjava funkcij in lastnosti gozdov posameznih tipov pokaže, da so si med seboj podobni sestojni tipi inicialno vrbovje, belo vrbovje in sivo jelševje. Gozdovi te skupine so pod vplivom talne vode in visokih poplavnih vod. Med funkcijami prevladujejo večinoma ekološke vloge gozda. Delež mehkih listavcev v lesni zalogi je velik, skupaj pa obsegajo gozdovi teh kategorij 62% površine vseh obrečnih gozdov na preučevanem območju. Bolj kot gozdnogojitveni posegi, ki so v teh gozdovih dokaj redki, so za te sestoje pomembne lastnosti okolja, ki omogočajo njihov obstoj (visoka nivo talne vode, odsotnost človeških posegov v rastišče in tok reke). Pomembna lastnost druge skupine, v katero uvrščamo sestojna tipa pionirski gozdovi višjih rečnih teras in obvodni koridorji, je pomanjkanje stika s talno vodo. V drevesni plasti teh tipov prevladujejo vrste, ki se pojavljajo na bolj sušnih rastiščih obrečnih gozdov (veliki jesen, lipovec, beli gaber, graden). Ker imajo ti gozdovi večji lesno proizvodni potencial je predvsem pomembna zmernost ukrepov in omejitev človekovih posegov, predvsem takih, ki imajo za cilj spremembo rabe zemljišča (paša v gozdu, krčitve). Ta razred obsega 30% površine analiziranih gozdov. V tretjo skupino obrečnih gozdov smo uvrstili antropomorfne gozdove v katerih so človeški vplivi že tako veliki, da ti gozdovi opravljajo predvsem socialne funkcije. Ta sestojni tip gozda, ki predstavlja 8% površine obrečnih gozdov, bi bilo smiselno upravljati kot park in ne kot gozdno površino. Usmerjanje obiskovalcev v to področje bi ostale, bolj ohranjene sestojne tipe razbremenilo pritiska človeških dejavnosti (turizem, rekreacija, gradbeni posegi). Na osnovi rezultatov analize rasti in prirastka najpogostejših drevesnih vrst obrečnih gozdov preučevanega območja lahko zaključimo, da imajo predvsem siva in bela vrba, nekoliko manj pa tudi siva jelša, zelo velik višinski (vrba do 1,14 m/leto) , debelinski (vrba do 1,4 cm/leto) in volumski prirastek. Prav zaradi hitre rasti pa se osebki te vrste tudi hitro starajo. Ker je bilo območje severne Primorske poseljeno razmeroma zgodaj, je bil tudi pritisk na obrečne gozdove že v preteklosti zelo velik. Analiza starih kart je pokazala, da je bila do začetka dvajsetega stoletja površina obrečnih gozdov na analiziranem območju pod 50 ha. V procesu zaraščanja kmetijskih površin v Sloveniji, ki traja še danes, se je ta površina povečala na 229,16 ha. Naloga je pokazala, da preučevano območje ni neokrnjena divjina temveč tako kot skozi celotno zgodovino tudi danes ostaja stičišče mnogoterih, pogosto tudi nasprotujočih si interesov. Izboljšanje stanja obrečnih gozdov na področju med Kobaridom in sotočjem z Tolminko lahko dosežemo le z upravljalskim načrtom, ki bo uskladil želje skupnosti in različnih strok. Tako bodo ti sestoji s primernim gospodarjenjem v prihodnosti lahko izkoristili ves potencial za nudenje ekosistemskih storitev v krajini in obdržali pomen ki ga nedvomno imajo.

Assessing biophysical forest parameters such as Leaf Area Index (LAI) and canopy height is of vital importance for monitoring forest productivity. This study provides an evaluation of canopy parameter retrieval through the forest growing season using a combination of two low cost digital optical imagery techniques. Fieldwork was conducted in a small forest stand in Dryden Farm near Edinburgh, at three development stages from April to June 2016. Hemispherical photography from below the canopy was used to calculate LAI and light transmission. These were compared to canopy area estimated using UAV imagery from the top, suggesting that UAVs can be used to assess changes in leaf area through time. The Structure-from-Motion (SfM) technique from the UAV images was evaluated for creating 3D models. Their accuracy was calculated using field measurements as a validation method. The results of this study showed that SfM performed well for producing accurate Digital Surface Models (DSMs) only during leaf-on acquisitions (resolution 4.86cm pixel-1) due to the increased penetration in conditions without foliage. The DSM was used to assess the SfM method for estimating tree heights. A significant strong positive correlation was observed between the model derived canopy heights and field measurements (R2=0.96, RMSE=81cm). The Ground Control Point (GCP) method assessed the horizontal accuracy and produced a RMSE of 1.37m, which is considered suitable for forestry applications. This study concludes that a combination of these imagery techniques can be utilised to estimate and compare forest stand parameters through and between growing seasons with adequate accuracies, at very low costs.

While various relationships between productivity and biodiversity are found in forests, the processes underlying these relationships remain unclear and theory struggles to coherently explain them. In this work, we analyse diversity–productivity relationships through an examination of forest structure (described by basal area and tree height heterogeneity). We use a new modelling approach, called ‘forest factory’, which generates various forest stands and calculates their annual productivity (above-ground wood increment). Analysing approximately 300 000 forest stands, we find that mean forest productivity does not increase with species diversity. Instead forest structure emerges as the key variable. Similar patterns can be observed by analysing 5054 forest plots of the German National Forest Inventory. Furthermore, we group the forest stands into nine forest structure classes, in which we find increasing, decreasing, invariant and even bell-shaped relationships between productivity and diversity. In addition, we introduce a new index, called optimal species distribution, which describes the ratio of realized to the maximal possible productivity (by shuffling species identities). The optimal species distribution and forest structure indices explain the obtained productivity values quite well ( R 2 between 0.7 and 0.95), whereby the influence of these attributes varies within the nine forest structure classes.

На основании лесоустроительных баз данных и материалов собственных исследований авторов предпринята попытка распределения насаждений Уральского учебно-опытного лесхоза (УУОЛ) Уральского государственного лесотехнического университета (УГЛТУ) по группам типов леса, лесным формациям и группам полнот. Указанные распределения выполнены отдельно для насаждений с разным породным составом древостоев. С учетом комплексного анализа полученных данных, основных лесоводственных требований, предъявляемых к проведению различных видов рубок спелых и перестойных насаждений, а также рубок ухода, разработаны и предложены критерии проведения опытных рубок, позволяющих предотвратить нежелательную смену пород и обеспечить переформирование производных мягколиственных древостоев в коренные хвойные насаждения, не прибегая к искусственному лесовосстановлению. Реализация критериев облегчит составление программ научных исследований по изучению лесоводственной эффективности различных видов рубок спелых и перестойных насаждений, а также будет способствовать освоению учебных дисциплин по направлениям «Лесное дело», «Технология лесозаготовительных и деревообрабатывающих производств». On the base of forest management data base and authers personal researches data an attempt was made to distribute the stockings according their forest types, forest formation the degree of density. The above given distribution (classifi cations) has been carried out separately for the stocmings with varions species stocking composition. Taking into account the complex analyses of data obtained and the main silvicultural requirements necessary to carry out varions kinds of mature and overmature stocmings cutting and improvement cutting some criteria for experimental cutting carrying on has been worked out and recommended. At will make possible to prevent unfavour able species change and quarantee reforming og derivated soff wooded stocmings into native evergreen stormings avoiding reforestation. The criteria realization will facilitate the scientifi c research programmes to study silvicultural effectiveness of mature and overmature different kinds ofi fferent kinds of working out as well as to promote mastering such academic subjects as logging and woodworking processes technology.