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Climate change increases the vulnerability of relict forests. To address this problem, regional Forest Services require silvicultural and conservation actions to designate specific forest management alternatives. In this context, the main objective of this study was to develop a methodology to map complex Abies pinsapo forest typologies using multispectral and low-density airborne LiDAR data and machine learning. Stand density, species composition and cover were used to identify seven forest typologies. Random forest resulted as the more accurate model (OA = 0.62; Kappa = 0.43) to classify those types based on multispectral and LiDAR data, although showing a moderate model performance. Classification performance showed great differences between forest types with better results for the uneven-aged stands compared to the even-aged and two-aged stands. The developed typology was applied to supply local forest managers with more accurate forest maps that can be used to improve forest management plans. The typology proposed is easy to apply in forest management practices since it only uses as input the diameter at breast height, tree density and specific composition. The study demonstrated the potential of low-density LiDAR data combined with spectral information from high-resolution orthophotos to predict the structural characteristics of complex forest typologies. [ABSTRACT FROM AUTHOR]

Climate change increases the vulnerability of relict forests. To address this problem, regional Forest Services require silvicultural and conservation actions to designate specific forest management alternatives. In this context, the main objective of this study was to develop a methodology to map complex Abies pinsapo forest typologies using multispectral and low-density airborne LiDAR data and machine learning. Stand density, species composition and cover were used to identify seven forest typologies. Random forest resulted as the more accurate model (OA = 0.62; Kappa = 0.43) to classify those types based on multispectral and LiDAR data, although showing a moderate model performance. Classification performance showed great differences between forest types with better results for the uneven-aged stands compared to the even-aged and two-aged stands. The developed typology was applied to supply local forest managers with more accurate forest maps that can be used to improve forest management plans. The typology proposed is easy to apply in forest management practices since it only uses as input the diameter at breast height, tree density and specific composition. The study demonstrated the potential of low-density LiDAR data combined with spectral information from high-resolution orthophotos to predict the structural characteristics of complex forest typologies.

The analysis of the developed classification schemes of forest hunting grounds is given. Previously, forest typology was taken as a basis with a 4-level division (category-class-group of types-type). The authors adhere to this scheme, but give environment-forming arguments and criteria for their selection. An analysis of the main literature on the classification of forest hunting grounds shows the evolution of the classification of natural resources from the use of available information (forest planning materials) to the specific assessment of productivity displayed on satellite images. Any thematic interpretation of the natural basis does not correspond to the tasks of hunting management. Animals are mobile, and the forest environment is dynamic, so the classification of hunting grounds should take into account the spatial and successional factors in the formation of habitat conditions. The proposed scheme takes into account at the level of the range the action of climatic (zonal, altitudinal-zone), population-ecological (forage, protective and nesting) and population dynamics-succession (dynamics of stands) factors. When hunting planning, the already available materials of forest planning and former hunting planning are taken into account, but the thematic interpretation of the original information must be also considered. A direct interpretation of the ecological properties of the image of hunting grounds from satellite images is proposed, and the developed classification scheme of the dynamic state makes it possible to predict their successional productivity and the level of animal abundance. Therefore, one should focus on obtaining direct information about hunting grounds using high-resolution satellite imagery.

Considering the changing climatic conditions, the Czech and Slovakian vegetation has been vertically divided into Forest Vegetation Zones (FVZs) units. Each FVZ is represented by a specific tree species, i.e., the oaks (Quercus sp.), European beech (Fagus sylvatica L.), silver fir (Abies alba Mill.), Norway spruce (Picea abies (L.) H. Karst.) and dwarf pine (Pinus mugo Turra). The FVZ concept has been applied in the Czechoslovakian forestry classification practice since the 1950s. Due to the broad time span of the studied topic, this article is divided into five chapters regarding the evolution of the FVZ concept. Its currently applied form was established primarily in the 1970s on the grounds of data gathered during two decades of forest typology research. An FVZ unit has become an upper unit of the Czech Forest Ecosystem Classification since its legislative codification in the Forest Act (289/1995) in 1995. To this day, however, the FVZ concept has not been reassessed by advanced, multi-dimensional statistical methods. This paper aims to describe key moments of the development of this concept and provide a perspective on its limitations, also in connection with current trends in ecological research. This review aims to provide a better understanding of the forest vegetation-environment relationship in the Czech Republic in relation to climate change, indirect anthropogenic environmental impact, and prediction of forest and landscape ecosystems response [ABSTRACT FROM AUTHOR]

Forest typology is yet to get sufficiently integrated into related ecological and geographical sciences. The succession of plant phytocenoses necessitates constant adjustments to forest types. The discussed studies have been conducted to improve the classification of forest types in the Ukrainian Carpathians and bring the description closer to the actual distribution of vegetation within the studied area. The paper provides a detailed analysis of forest typology research for the Ukrainian Carpathians area during late 20th and early 21st century. The forest fund areas of the Carpathian region, which are subordinated to the State Agency of Forest Resources of Ukraine, have been classified by forest vegetation types. Total area of subor and coniferous forest types is 1,493.1 ha and 28,910.2 ha, respectively. The study involved establishing of permanent sample plots on the territory of nature protection institutions and forest management enterprises. According to the findings, it is proposed to complement the classification of subor and coniferous forest type as defined by Z.Yu. Herushynskyi on the territory of the Ukrainian Carpathians with the following types: fresh pine subor forest type, wet pine subor forest type, and wet pine coniferous type. The paper defines the main diagnostic features of the suggested forest types. These subor and coniferous forest types can be clearly distinguished from other forest types by soil and hydrological conditions, and can be used to describe the corresponding forest vegetation types. The correctness of definition of new forest types is confirmed with a set of plant indicator species that have been identified within the relevant areas. The findings provide a better understanding of forest ecology and make a significant contribution to forest typology studies on the territory of the Ukrainian Carpathians. Another step towards researching the patterns of the establishment of plant complexes in the Ukrainian Carpathians has been taken. Forest formations of the Carpathians are presented in more detail in forest typological science

Th e concept of zonality (zonal concept) or azonality of vegetation has been well known for a long time all over the world. In the Czech Republic (CZ), this topic is usually presented in a context of (forest or forest site) ecological classification systems, called informally “forest typology” or officially “the Czech Forest Ecosystem Classification”. Expert-based vegetation zonality has not been tested so far. Th ere is even no relevant ecologically-based review of the concept and linked ecological principles behind classification systems. Th e latest modest note dealing with the zonal concept has been published along with the Notice 298/2018 of Forest Law (Typology table). Th is review summarizes (i) brief history on the zonal concept, (ii) definition of zonal and azonal vegetation, and description of parameters of a zonal site, (iii) approaches of (forest) classification systems around the world, and (iv) main principles of the Czech Forest Ecosystem Classification. Results of this review should be used as a theoretical basis for a next rigorous analysis of the concept and system units, based on data, sampled during the second cycle of the National Forest Inventory 2011–2015. [ABSTRACT FROM AUTHOR]

Measurement of water content in forest habitats is considered essential in ecological research on forests, climate change, or forest management. In the traditional forest habitat classification, two systems of habitat conditions analysis are found: single factor and multifactor methods. Both are laborious and therefore costly. Remote sensing methods provide a low-cost alternative. The aim of the presented study was to find the relationship between the spectral indices obtained from satellite images and the forest habitats moisture indices used traditionally in the Polish forest habitats classification. The scientific hypothesis of the research is as follows: it is possible to assess the variation in the humidity of forest habitats on the basis of spectral indices. Using advanced geographic information system (GIS) technology, 923 research plots were tested, where habitat studies performed with the traditional methods were compared with the analysis of 191 spectral indices calculated for Sentinel-2 image data. The normalized difference vegetation index (NDVI) has proved to be the most useful to the assessing of moisture of forest habitats. The ranking of the most correlated indices was calculated as Eintg—the product of the absolute value of the slope and the mean square error complement, and for the top five indices was as follows: NDVI = 0.248619, EXG = 0.242112, OSAVI = 0.239412, DSWI-4 = 0.238784, and RDVI = 0.236995. The results also highlight the impact of water reservoirs on the humidity and trophicity of forest habitats, showing a decrease in the fertility of habitats with an increase in distance from the water reservoir. The results of the study can be used to preparing maps of the diversity of forest types, especially in hard-to-reach places, as well as to assess changes in the moisture status of habitats, which may be useful, for example, in the assessment of the fire risk of forest habitats. We have proved that NDVI can be used in applications for which it was not originally designed. [ABSTRACT FROM AUTHOR]

Productive European beech stands (Fagus sylvatica L.) involving Scots pine (Pinus sylvestris L.) are formed in Ukrainian Roztochie. Considering value and limited distribution of beech stands involving pine in tree species composition, it is necessary to work out and implement measures for their natural restoration in connection with the climate change and the efficient use of raw materials and non-wood products. Main forestry and management indices of beech stands that include pine in tree species composition were analysed. Forestry activities that are currently carried out in middle-aged and maturing stands significantly reduce their relative completeness and growing stocks, as determined by comparing growth particularities of productive beech stands from different sources. [ABSTRACT FROM AUTHOR]

Copyright of ACTA Scientiarum Polonorum Silvarum Colendarum Ratio et Industria Lignaria is the property of Poznan University of Life Sciences Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The concept of forest as the unity of growing stock (living tree component), climate and soil, that is, as ecosystems, was first defined by A.A. Krüdener. The scientist has developed a classification of forests according to the fertility of the soils on which they grow, in the coordinates of their provision with nutrients and moisture. A.A. Krüdener proposed the first ecological classification of forests of European Russia on the principle of zoning its territory according to the main climatic indicators, with the subsequent division of forests within climatic zones and regions into types of stands according to the peculiarities of the petrographic composition and water regime of soils. A.A. Krüdener, like G.F. Morozov, assigned the decisive role to the soil conditions in the formation of types of stands in the midst of homogeneous climatic areas, emphasizing that the main factor is not the soil itself as such, but the soil as a substrate, as a medium for plant growth. The scientist, in the process of intensive study of soils of different types of forest, revealed a close relationship of the nature of forest vegetation, not with the genetic types of soils, but with their fertility, and with their forest growth potential. In so doing, to assess soil fertility, A.A. Krüdener used a new approach - the phytoindication method, that is, the vegetation, its composition and productivity were accepted as a criterion for the quality of soils. In developing the classification of forests, A.A. Krüdener clearly adhered to the coordinate principle of soil quality assessment by the two main components of their fertility - the supply of nutrition and moisture, which became the determining factor in all subsequent classifications of the forest typology of the G.F. Morozov school. The total measure of fertility of the environment is the amount, proportion and distribution by seasons of limited environmental resources - heat, moisture and nutrition. Forest typological classification models are constructed in the coordinates of these resources – the climate grid in the coordinates of heat and atmospheric humidity, edaphic – in the coordinates of nutrition and soil moisture. Therefore, they can be used not only to classify forests, but also nature in general. The article also describes the main achievements of the Ukrainian Ecological School of Forest Typology formed on these principles. The existing shortcomings and issues that need to be further addressed are noted.

When ordinating plots of tropical rain forests using stand-level structural attributes such as biomass, basal area and the number of trees in different size classes, two patterns often emerge: a gradient from poorly to highly stocked plots and high positive correlations between biomass, basal area and the number of large trees. These patterns are inherited from the demographics (growth, mortality and recruitment) and size allometry of trees and tend to obscure other patterns, such as site differences among plots, that would be more informative for inferring ecological processes. Using data from 133 rain forest plots at nine sites for which site differences are known, we aimed to filter out these patterns in forest structural attributes to unveil a hidden pattern. Using a null model framework, we generated the anticipated pattern inherited from individual allometric patterns. We then evaluated deviations between the data (observations) and predictions of the null model. Ordination of the deviations revealed site differences that were not evident in the ordination of observations. These sites differences could be related to different histories of large-scale forest disturbance. By filtering out patterns inherited from individuals, our model analysis provides more information on ecological processes.

As of 2019, the total area of forest stands with the varying proportion of Scots pine (Pinus sylvestris L.) and beech (Fagus sylvatica L.) in composition on the Ukrainian Roztochchia was 11,251.3 ha and the area of pine stands involving European beech in composition was 6879.5 ha. Pine stands involving beech in composition are formed on the fresh, moist and boggy relatively pure and relatively rich soil condition. Pine forest stands (average share of pine exceeds 56%), which include beech in composition occupy more than 80% of the total area of interest. Mature and overmature forest stands dominate most of the landscape. More than 85% of stands are characterized by an average relative completeness. Undergrowth of deciduous tree species, which is mainly formed by European beech or hornbeam (Carpinus betulus L.) and rarely by common oak (Quercus robur L.) or sycamore maple (Acer pseudoplatanus), is available under a canopy of middle-aged, ripening and mature stands. The study points to the need to rethink forest management approaches and eventually to use such methods of forest cuttings that ensure natural regeneration not only of a European beech and common oak, but primarily of a pine. The practice of creating pine plantations in such conditions favourable for its growth and development should be used only in those cases when it is impossible to achieve natural regeneration of pine. [ABSTRACT FROM AUTHOR]

Measurement of water content in forest habitats is considered essential in ecological research on forests, climate change, or forest management. In the traditional forest habitat classification, two systems of habitat conditions analysis are found: single factor and multifactor methods. Both are laborious and therefore costly. Remote sensing methods provide a low-cost alternative. The aim of the presented study was to find the relationship between the spectral indices obtained from satellite images and the forest habitats moisture indices used traditionally in the Polish forest habitats classification. The scientific hypothesis of the research is as follows: it is possible to assess the variation in the humidity of forest habitats on the basis of spectral indices. Using advanced geographic information system (GIS) technology, 923 research plots were tested, where habitat studies performed with the traditional methods were compared with the analysis of 191 spectral indices calculated for Sentinel-2 image data. The normalized difference vegetation index (NDVI) has proved to be the most useful to the assessing of moisture of forest habitats. The ranking of the most correlated indices was calculated as Eintg—the product of the absolute value of the slope and the mean square error complement, and for the top five indices was as follows: NDVI = 0.248619, EXG = 0.242112, OSAVI = 0.239412, DSWI-4 = 0.238784, and RDVI = 0.236995. The results also highlight the impact of water reservoirs on the humidity and trophicity of forest habitats, showing a decrease in the fertility of habitats with an increase in distance from the water reservoir. The results of the study can be used to preparing maps of the diversity of forest types, especially in hard-to-reach places, as well as to assess changes in the moisture status of habitats, which may be useful, for example, in the assessment of the fire risk of forest habitats. We have proved that NDVI can be used in applications for which it was not originally designed.

Questions: Forest classifications are tools used in research, monitoring, and management. In Finland, the Cajanderian forest site type classification is based on the composition of understorey vegetation with the assumption that it reflects in a predictable way the site's productive value. In Russia, the Sukachevian forest classification is similarly based on understorey vegetation but also accounts for tree species, soil wetness, and paludification. Here we ask whether Cajander's and Sukachev's forest types are effectively the same in terms of species composition, site productivity, and biodiversity. Location: Boreal forests on mineral soils in Finland and the Russian part of Fennoscandia. Methods: We use vegetation and soil survey data to compare the Cajanderian and the Sukachevian systems in terms of the understorey community composition (that is supposed to define them), soil fertility and tree productivity (that they are expected to indicate), and biodiversity (that is of interest for conservation purposes). We create and employ class prediction models to divide Russian and Finnish sites into Cajander's and Sukachev's types, respectively, based on vegetation composition. We perform cross‐comparisons between the two systems by non‐metric multidimensional scaling ordination and statistical tests. Results: Within both systems, the site types formed similar, meaningful gradients in terms of the studied variables. Certain site types from the two systems were largely overlapping in community composition and arranged similarly along the fertility gradient and may thus be considered comparable. Conclusions: The Cajanderian and the Sukachevian systems were both developed in the European boreal zone but differ in terms of the exact rules by which site types are determined. Our results show that analogous types between the systems can be identified. These findings aid in endeavours of technology and information transfer between Finnish and Russian forests for the purposes of basic or applied ecological research and forest management. [ABSTRACT FROM AUTHOR]

The necessity of the doctrine for the soil as a plants habitat environment revival, which appeared in the early stages of the agriculture development, is substanti-ated. The conditions which ensure sustainable growth and high productivity of various crops were determined. First of all, we studied the specificities which determine the ability of soil to provide plants with nutrients and moisture, largely due to the composition and structure (topography) of the soil-forming rocks, their texture (due to the different mineral composition of different size particles) and therefore largely determines soil fertility. The main credo of this scientific approach is the study of soil properties in relation to plant life (P. A. Kostychev). V.V. Dokuchaev determined soils as a special natural body, which requires corresponding approach to their study, regardless of the vegetation, which cover the soil surface. Emerging on these principles, a new direction of soil science, which later obtained the name of genetic, concentrating on the study of the soil itself, moved away from the demands of agricultural produc-tion, entering into the category of academic sciences. The principles and achievements of the ecological school of forest typology, which studies soils from the position of the unity of both directions, are characterized on the basis of N.М. Sibirtsev suggestions which were described in his classification of 1895. This allowed researchers to bring into a strict system the whole diversity of forests from different natural zones, and made it possible to predict their composition and productivity. At the same time, the number and ratio of three limiting ecological resources: heat, moisture, and food — which determine the composition and productivity of vegetation and the productivity of soils — prevail in the classification. This made it possible to characterize the main regulations of the relationship between living and inorganic nature, which V.V. Dokuchaev called the essence, the core of natural science. The soil science otains the opportunity to enter on the position of the basic theoretical base of agriculture. These principles exist in the community of US soil scientists for a long time. Developing global classification constructions (approximations), American soil scientists distinguish the main taxa (soil series) at the local agricultural level by primary rocks, taking into account their availability of food, moisture, and sometimes heat.

Arthur G. Krylov – doctor in biology, well-known specialist in geobotany, typology of Siberian forests, developed the classification of the Siberian stone pine forest types and generalized classification of forest life forms in the North Eurasia. The mountains of Altai, Far East and Caucasus, the West-Siberian plain forests, were studied during his long expedition life.

To avoid ecosystem degradation, forestry planning needs to be based on current information about the state of forest environment. Phytoindication is an inexpensive tool that allows tracking the environmental change at fine spatial scales. The present study uses this approach to assess changes within abiotic conditions of forests in the area of the Moravian-Silesian Beskids Mts. (Czech Republic). Phytosociological relevés collected in 2013 at 118 permanent plots were compared with records from the 1960s and 1970s. The changes were expressed using average Ellenberg's Indicator Values and units of the Czech Forest Typological System. Persisting soil acidification was detected, and linked to industrial deposition and planting of Norway spruce beyond its natural range. Conversion towards a higher share of broadleaved species was suggested to support soil recovery.

Structuring forest communities is considered as a pre-studying procedure. The paper defines the fundamental structuring terms and describes the theory behind it. Factors hampering forest typology development are discussed. The areas of forest typology promising regarding sustainable and multi-purposed forest management are outlined.

The Russian Federation is one of many countries that have signed the Montreal Protocol and Pan-European Forest Process. These initiatives are aimed at harmonizing national forest inventory systems with criteria and indicators for sustainable forest management. In Russia, the classification of forest type is at the heart of national forest inventory systems. For various historical reasons, Russian scientific advancements in the field of forest typology remain little known in the rest of the world. This paper is aimed at addressing this deficiency. Here, we provide an overview of the main trends in the field of forest typology studies in the previous political states of the Russian Empire, the Soviet Union, and the Russian Federation from the end of the nineteenth century to the beginning of the twenty-first century. We detail the principles that formed the basis of the most significant forest type classifications. We also perform similarity and differences analyses comparing approaches used by members of different scientific schools in the field of forest typology. The historical relationship between ecological, phytocoenotic, genetic, and dynamic forest type classifications are discussed as well as the reasons for the prevalence of certain forest type classifications in different regions of Russia. [ABSTRACT FROM AUTHOR]

Differentiation of forest technologies according to ecosystem properties is a necessary step to achieve sustainable forestry. A forest typological system is considered to be the basic unit of ecosystem differentiation in the Czech Republic. Terrain characteristics, potential water erosion and applicable harvest technology were examined for 44 forest sites in a landscape segment of the Jizerské hory Mts. Forest site was found homogeneous in terms of terrain and technological properties. Edaphic category and groups of forest types as higher classification units and management sets as units of alternative classification showed lower homogeneity insufficient for operational planning.

Most Costa Rican forests have been intensively studied in recent years. One exception is the transition zone from lowland wet forest to the high elevation Quercus forest belt at the pacific slopes of the Cordillera de Talamanca. An inventory of secondary forest composition, structure and diversity was done on a specific slope (1150- 2300-m elevation) in the conservation and development project Amisconde. Thirteen plots of 500 m² were evenly spread along an elevation gradient. Specimens were collected of all woody individuals ( 3 cm DBH), dried, placed in a herbarium of morphospecies and afterwards identified. In total 90 genera within 49 families were found. The vegetation was separated in three forest types using TWINSPAN classification. Forest types were elevation based. Elevation and forest age showed (overall) no correlation with diversity using ANOVA, with the single exception of a positive correlation of the number of genera and elevation. This was opposite to the negative correlations mostly found on elevation gradients. The main factors for this positive correlation were the level of recent disturbance and the distance to primary forest, in combination with forest age.

Forest typology holds the central position in modern forestry. We give an overview of research on forest typology in Russia. Forest typology in Russia actively developed and improved with respect to requests forestry throughout the entire period of its existence. It remains the necessary basis for preserving the biodiversity of land ecosystems and ensuring sustainable forest management amid the growing anthropogenic impact and climate change. The birth of scientific forest typology is associated with the name of G.F. Morozov. A biogeocoenotic approach to forest classification was offered by V.N. Sukachev. V.N. Sukachev developed classifications for boreal forests which had been little affected by economic activity. The biogeocoenotic approach proved effective there. However, when literally applied to commercial forests, the biogeocoenotic approach sometimes failed to deliver satisfying results. The exponential shrinkage of natural forests and the increasing share of dynamic secondary growth brought about the need to reflect the time-related forest changes in classifications. The origins of the genetic approach can be found in the writings of G.F. Morozov. The first satisfactory geo-genetic forest classification was built by B.A. Ivashkevich. B.P. Kolesnikov provided the theoretical grounding and main postulates for the approach. According to B.P. Kolesnikov, a geographical and genetic classification means a classification based on the forest origin and evolution patterns which takes account of all the forest ecosystem stages and can be used to predict their future changes. Currently forest typology develops as an interdisciplinary science. It integrates forestry, geobotanics, forest taxation, soil sciences, biogeography, geology, and landscape ecology. A new methodology is being developed. It is a synthesis of forest ecology and synergetic. It uncovers new reserves for the forest science development. [ABSTRACT FROM AUTHOR]

Highlights: [•] The comparison of support for afforestation from European Agricultural Fund for Rural Development and costs for afforestation is presented. [•] The costs were calculated for 43 groups of forest site types based on forest typology. [•] The necessity of diversification of support according the national or regional needs and conditions. [ABSTRACT FROM AUTHOR]

Abstract: This study was concerned with the problem of application of the individual-based EFIMOD model to spatially explicit simulations on a regional scale. Three large forest areas with a total area of about 17,000 km2 with distinct environmental conditions were chosen. We used a set of simulation scenarios, taking into account both the regime of forest management and natural disturbances. The procedure of model initialization was suggested using conceptions of soil and forest types. [Copyright &y& Elsevier]

Phytophagous eriophyid mites Acalitus rudis (Canestrini) and Eriophyes leionotus (Nalepa) (Acarina, Eriophyidae) occurr in the area of the eastern Ore Mountains (northwest Czech Republic). Basedon the evaluation of site and climatic conditions, they prefer lower parts of crowns of birch stands aged over 40 years located at 500-700 m alt., the 5th forest vegetation zone (Abies-Fagus), 6th forest vegetation zone (Picea-Fagus) and 7th forest vegetation zone (Fagus-Picea) and their edaphic categories K (acidophila) and S (mesotrophica). The intensity of attack was affected mostly by the host standtraits. Climate of attacked stands was characterized by long-term precipitation amounts of 700-1000 mm and mean annual temperatures 4.5-6°C, even though climate influenced only occurrence of A.rudis. Effects of air pollution on the occurrence of Eriophyidae were not proved probably due to their low population density. Gradual increase in population density of E. leionotus can be related to the decline of the air pollution load in the area of investigation. [ABSTRACT FROM AUTHOR]

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work emphasises the usefulness of hemispherical photography for identifying spatial patterns in the tropical rain forest structure. Structural variability was investigated at a local (intra-site) scale, in relation to the forest mosaic, and at a regional (inter-sites) scale, for its implication in forest typology. Four primary forest sites, from 0.6 to 1 ha, were investigated in Central Sumatra, Indonesia. In a first instance, a qualitative analysis of the forest 3-D structure was found to be very helpful in the interpretation of quantitative results related to forest dynamics. The quantitative analysis was undertaken through the assessment of three structural characteristics: (1) the canopy openness (CO), or visible sky as seen from all directions of the hemisphere, (2) the spherical variance (SV), which quantifies the spatial dispersion of gaps and, (3) the plant area index (Lp), defined as half the surface area of canopy elements per unit ground area. At the local scale, maps of the CO values gave an indication about disturbance location and extent, providing an interesting document for studies on forest dynamics. At the regional scale, between-sites comparisons of CO, SV and Lp values added new information on forest structural differences when compared to dendrometric measurements. These results emphasised the fact that rain forest may exhibit high structural variability, even within a same bioclimatic region and a narrow altitude range. Hemispherical photographs could be a quick means of further investigating this spatial variability and it's relation to physical environment, thus providing information that is crucial for the refining of forest typology in the area. [ABSTRACT FROM AUTHOR]

Key message: We present a novel approach to define pure- and mixed-forest typologies from the comparison of pairs of forest plots in terms of species identity, diameter, and height of their trees. Context: Forest typologies are useful for many purposes, including forest mapping, assessing habitat quality, studying forest dynamics, or defining sustainable management strategies. Quantitative typologies meant for forestry applications normally focus on horizontal and vertical structure of forest plots as main classification criteria, with species composition often playing a secondary role. The selection of relevant variables is often idiosyncratic and influenced by a priori expectations of the forest types to be distinguished. Aims: We present a general framework to define forest typologies where the dissimilarity between forest stands is assessed using coefficients that integrate the information of species composition with the univariate distribution of tree diameters or heights or the bivariate distribution of tree diameters and heights. Methods: We illustrate our proposal with the classification of forest inventory plots in Catalonia (NE Spain), comparing the results obtained using the bivariate distribution of diameters and heights to those obtained using either tree heights or tree diameters only. Results: The number of subtypes obtained using the tree diameter distribution for the calculation of dissimilarity was often the same as those obtained from the tree height distribution or to those using the bivariate distribution. However, classifications obtained using the three approaches were often different in terms of forest plot membership. Conclusion: The proposed classification framework is particularly suited to define forest typologies from forest inventory data and allows taking advantage of the bivariate distribution of diameters and heights if both variables are measured. It can provide support to the development of typologies in situations where fine-scale variability of topographic, climatic, and legacy management factors leads to fine-scale variation in forest structure and composition, including uneven-aged and mixed stands. [ABSTRACT FROM AUTHOR]