bluuebunny/crossref_metadata_2025 huggingface dataset:
Rehabilitation of forest ecosystem on former heathlands by a first generation of Scots pine
Authors: Lust N. , Maddelein D. , Meyen S.
Published: July 2016

In an  attempt to rehabilitate degraded heathland areas, an important  reafforestation program, based on the introduction of Scots pine, was  executed at the end of the 19th century. Today, after one generation of Scots  pine, results can be considered to be very good. On various locations a dense  substratum, dominated by red oak and black cherry, has settled  spontaneously under the pine canopy. This  offers serious opportunities to conduct an indirect conversion towards mixed  oak-pine forests or oak-dominated deciduous forests. Massive presence of  black cherry in the understory of many pine stands inhibits the settlement of  other deciduous tree species or pine regeneration and thereby prevents the  stand conversion. The reintroduction of autochtonous tree species by  underplanting or sowing under pine canopy deserves recommendation, keeping in  mind the lack of seed trees and the high browsing damage on all seedlings  present. In absence of an understory a second pine generation can settle  under canopy of an older pine stand. Natural regeneration is also dominated  by Scots pine on the clearcutted areas and under canopy when the soil  vegetation and organic horizons have been removed. Summarising, we can state  that one generation of Scots pine has created various possibilities for the  development of a complex, diverse and structural forest ecosystem. It is the  task of the forest manager to fully turn to account these possibilities.
Growth, structure and shape characteristics of a 12 year old grey alder stand (Alnus incana L. Moench.)
Authors: Lust N.
Published: July 2016

In the  experimental forest Aelmoeseneie at Gontrode (Belgium), a 12 year old  artificial plantation of grey alder has been analysed on growth, structure  and shape characteristics.     In the plot some ten tree cells and tree pairs were examined in particular.  The tree cells consisted of one central tree, which was surrounded by six  other ones. The tree pairs were the dominant tree and the most dominated tree  in these cells.    In the first place height, diameter, basal area and leaf mass were determined.  Then, the vertical and horizontal structures were analysed, with special  attention being paid as well to the social differentiation in the tree cells  as to the crown areas. Finally, several tree shape characteristics were  determined.     The alder grew very well. The internal competition and differentiation had  already started. The position of the dominant trees, however, is not  stabilised yet.     The treatment of the thicket, in continuity with the thinning, will be  necessary in the next future.
Thin section preparation of poplar tree-rings for computer-aided image analysis in dendrochronological investigations
Authors: Amparado R. F. , Beeckman H. , Lemeur R.
Published: July 2016

A  methodology is outlined to measure histological poplar treering variables  like vessel area, being sensitive ecological indicators.     Thin section preparation methods and a staining schedule are suggested to  enhance contrast and to obtain best intensity colour for subsequent analyses  of poplar treering variables, using a computeraided image analysis technique.
Structure and dynamics of a 215-years old broadleaved forest stand recently installed as a total forest reserve
Authors: Van Den Berge K. , Roskams P. , Verlinden A. , Quataert P. , Muys B. , Maddelein D. , Zwaenepoel J.
Published: July 2016

Since  1983, a 215-years old broadleaved stand in the state owned Zoniën Forest  (Belgium, Flanders) has been withdrawn from all silvicultural treatments.      Thanks to the completely reviewed forest law in Flanders of 1990, the stand  is now officially installed as a total forest reserve.     The present contribution gives an overview of the principal site  characteristics, and then focuses on the woody component of the ecosystem.  Stand structure analysis starts from the situation of 1986, i.e. dating from  before the spring tempests of 1990.     Subsequently, the impact of those gale forces is evaluated as a driving  factor in forest dynamics. In this particular stand, it was found that an  abrupt change-over took place from the regeneration phase to a real decaying  phase, resulting in a mosaic pattern with remnants of the old stand,  consolidated regeneration, canopy gaps and windfall areas of different  size.
Schwerpunkte des neuen Forstdekretes in Flandern
Authors: Lust N.
Published: July 2016

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The attitude of the Flemish private forest owner towards multiple use forestry and the new forest decree
Authors: Lust N.
Published: July 2016

The  importance of private forest in the multiple use forestry in Flanders should  not be underestimated. Generally speaking, the attitude of the private forest  owner is far from negative. Practice has shown some positive achievements.  The private forest owner is not only interested in wood production and  investment, but he also takes a very keen interest in hunting, nature  conservation and recreation. Forest legislation is a good means to increase  the significance of multiple use forestry in private forests. In this  respect, the recent Flemish Forest Decree makes a considerable contribution,  on the one hand by imposing some obligations, such as a management plan, and  on the other hand by promoting wood production as well as forest  conservation, recreation and nature development in the forest.
Le bois comme composant d'écosystème
Authors: Beeckman H. , Vander Mijnsbrugge K.
Published: July 2016

Wood as an ecosystem component - An  ecological study of wood as a material has to define two ecosystems of a  different level of integration.     The small-scale ecosystems are the dwelling houses, where a considerable  amount of wood is used for several purposes. Positive effects of wood on the  health of the inhabitants are reported. These effects establish the  significance of the typical association wood-mankind.     The large-scale ecosystem is the global ecosystem of the earth. Ecological  diagnostics on this level have to take into account the Second Law of  Thermodynamics. Forestry and intelligent use of wood are able to slow down  entropy and heat accumulation in the atmosphere.
Silvicultural characteristics of a Scots pine stand on drift sands
Authors: Maddelein D. , Lust N.
Published: July 2016

The  study of a seventy years old stand of Scots pine on drift sands proves that  Scots pine growth on these sites was and is still relatively good: average  diameter 27.6 cm, average height 19.4 m, standing volume 213 m3 and an annual increment  of 4.9 m3.ha-1.yr-1. All Scots pines  belong to the upper storey. Yet considerable differences in crown development  and vitality are observed. The current growth rate and the spontaneous  settlement of pine seedlings under canopy show the ideal conditions for the  creation of a high forest with reserves. Anyway a rotation period of more  than 70 years is recommendable.     On several places a consolidated regeneration of Scots pine seedlings under  canopy occur. Groups with a stem number of 700 to 3,500 seedlings per are, ranging  in age from 3 to 11 years and in height from 10 to 170 cm, are present. This  Scots pine regeneration has developed in a normal mor humus layer and in a  dense Deschampsia mat.      Broadleaved regeneration is not so abundant, and consists for 75 % of black  cherry. Absence of seed trees, browsing damage and the exclusive character of  black cherry are the limiting factors for the installation and survival of  valuable indigenous species, such as pedunculate oak.     Provided that black cherry is removed and that the regeneration is  protected against wild damage, it is possible to create a mixed forest  dominated by Scots pine but with a considerable admixture of indigenous  broadleaved trees. However, if black cherry will not be sufficiently  controlled, it can be expected that in a first phase black cherry will  dominate the understorey, that it will prevent the regeneration of all other  species and that, very soon, it will form an almost single-species dominated  stage in forest succession.
Forestry policy on multiple use forestry in Europe
Authors: Lust N.
Published: July 2016

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Knowledge modelling for a wood identification system
Authors: Vander Mijnsbrugge K. , Beeckman H.
Published: July 2016

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Justification technologique de l'utilisation de bois en menuiseries extérieures
Authors: Stevens M.
Published: July 2016
Some experiences with reafforestation of alang-alang (Imperata cylindrica L.) grassland in Indonesia
Authors: Pratiwi - , Lust N.
Published: July 2016

In  Indonesia the alang-alang grassland covers about 16-20 million hectares. It  is considered unproductive land, therefore reafforestation of this grassland  is very necessary. Some efforts including the policy of the Forestry  Department, on national level and even in the field have been done.     Some techniques to suppress the alang-alang growth have been tried out  including techniques of soil preparation, species selection and maintenance  of plantations.     The reafforestation programme of alang-alang grassland has promising  results for the increase of the forest area and will ultimately provide wood  production, as well as an income for the rural people and soil protection  benefits. The production of log and soft wood as raw material will increase.      The knowledge of silvicultural techniques for reafforestation activities in  alang-alang grassland is enough to start an action programme, but  nevertheless further research has to be done to find out still more  appropriate techniques and to achieve better results.     The reafforestation method on the alang-alang grassland will mainly depend  on the site situation and the objectives, especially the kind of wood that  must be produced. Reafforestation directly with fast growing species will be  carried out when soft wood will be produced. When more valuable wood should  be produced, the system will be :     1. Planting fast growing species.     2. After the alang-alang is suppressed the slow growing and more demanding  species is planted, while gradually the fast growing species is harvested.      A choice between exotic or indigenous species for forest plantation must be  done, considering very carefully the advantages and disadvantages of these  species. When the value, volume and production time of an exotic and an  indigenous species are comparable, the indigenous one is the preferred  choice. Use of exotic species is in principle only justified when a  sustainable forestry is assured. The reafforestation of alang-alang grassland  will create positive socio-economic impacts as well as environmental  impacts.
Ideas for an improved forestry education
Authors: Lust N.
Published: July 2016

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Heterogeneity in a poplar stand and estimation of the mean volume index
Authors: Moermans R. , Van Hecke P. , Mau F.
Published: July 2016

For a  small poplar stand of 81 Robusta trees (2 years old), contour mapping and  trend surfaces are calculated. These statistical techniques can be  informative for showing heterogeneity and can be helpful for estimating the  mean of the parameters concerned.     They can yield better estimates than random sampling in the stand. As  parameter, the Volume Index is used for demonstrative purposes.
Teak (Tectona grandis L.f.) forests in Java, Indonesia: plantations, management and policy
Authors: Pratiwi - , Lust N.
Published: July 2016

This  paper gives an overview of the environmental conditions, silviculture,  distribution and area of teak forests in Indonesia. As Java is a densely  populated island, the population pressure is also very high. Therefore  specific forest management systems are applied. The tumpangsari (taungya)  system as well as daily wage system are considered as having valuable social  and economic aspects for people of the area surrounding the teak forests.  This way they ultimately decrease further teak forests deterioration.     Indirect government policies (such as family planning and transmigration)  and policies aimed directly at the teak forests, such as application of the  tumpangsari and daily wage systems, could maintain teak forests and teak  production in Indonesia on a sustainable basis.
Zu einer Walderholungspolitik in Flandern
Authors: Lust N.
Published: July 2016

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Theoretische berekeningen van systematische fouten bij de bepaling van de oppervlakte van het grondvlak
Authors: Goossens R.
Published: July 2016

Theoretical  calculation of the systematic errors made during the determination of the  basal area - To prove his point, the author goes out from  the supposition, that the best approximation for the basal area is an  ellipse. Consequently three parameters are set up to reflect various  characteristics of a given area at any moment. The first parameter (V(t)) is  a measure for the form of the basal area at a moment t and is calculated from  the relation between the large (a) and the small (b) axis of the ellipse. The  use of a second parameter was necessary as the biological growth-centre of  the tree (point M in fig. 3) does not coincide in most cases with the  intersection 0 of the axes of symmetry. The distance between both points (M  and 0), represented by symbol x0(t) is used as a measure for the real stem  dish eccentricity. The third parameter is a measure for the size of the basal  area at a moment t and is called the representative radius (r(c; t)). It is  the radius of a circle with the same surface value as the considered ellipse.      Going out from these three parameters, a formula was worked out up to  basically calculate any r(u; t) in function of the direction u or the angle e  between this radius and the maximum radius (par. 3, form. 5) of any given  stem dish. As the value of x0(t) depends on the dimension of r(c; t), the  concept 'relative eccentricity e(t)' is introduced (cfr. Form. 6) and it  becomes thus possible to give the basic formula a definitive form (cfr. form.  7). By means of this basic formula, it is not only possible to calculate the  descriptive radius at a moment t in function of V(t), e(t) and θ, but a lot  of further deductions can also be made. A first possible application consists  in the calculation of the procentual error Er(u; t) on any radius r(u; t) in  function of V, e and their position regarding to the maximum radius (cfr.  par. 4 1, form. 8).    The evolution of this error in function of the mentionned parameters is  given in fig. 4.     In paragraph 42, the procentual error is calculated from each other on  average of 12 radii, measured at a distance of 300 (form. 8).     This is done in function of the relative eccentricity e and the form of the  basal area. The graphic representation of this calculations is given in fig.  5. In fig. 6 the evolution of the relative distribution SRx (t) on the  mentionned average is given. To calculate this distribution form. 10 was  used.     Paragraph 43 proves that the mentioned procentual errors only need to be  duplicated to know the procentual errors on the calculated surfaces of the  basal area.     Finally, the position of the representative radius has been verified in  function of e, and V and his evolution studied by using the formula 13 and  13' (fig. 7).
Elements of sustainable forest management
Authors: Lust N.
Published: July 2016

Elements  of the modern day vision on sustainable forest management are discussed. Some  aspects of the concept are analysed, focusing on the natural definition in  comparison with the ecosystem definition. The significance of ecological  stability is emphasized. It is pointed out that perhaps the most important  aspect of forest stability and sustainability is the ability to retain soil  fertility. Attention is paid to the importance of species composition, the  role of organic matter, the impact of forest use and the problems of forest  engineering.     In order to reach sustainable forest management, a number of strategies can  be applied, based either on the market or the state. There is a need for  measurable criteria and indicators for the evaluation of sustainability.  Therefore new programmes of scientific sampling or even basic research are  still needed.     Forest sustainability provides still a dramatic lot of questions and  efforts, a.o. on the potentiality of sustainable forestry.
Entwicklung mechanischer Stabilitätsmerkmale in Fichtenstangenhölzern in Oberösterreich
Authors: Huvenne P.
Published: July 2016

In  Central Europe, spruce forests play an important role in forestry and wood  production and cover large surfaces. This study focuses on the mechanical  stability of monocultural, evenaged spruce stands. Measurements were taken in  three different forests in the Western part of Oberösterreich (Austria). Two  of them belong to farmers, the third, the "Weilhartsforst" is run  as a private business. In 18 plots of 20 by 20 meters, an inventory of  diameter, height, crown length, social position and damage by deer was made.  This data were statistically analysed on al parameters in relation to  management and eld. The h/d ratio was used as main parameter, as it is in  many Austrian stability studies.     Generally , the mechanical stability of the spruce stands is insufficient,  which is the result of the treatment. A strong thinning, by cutting  neighbouring trees of all candidates will give a satisfactory h/d ratio.  There was found that a first stern reduction should take place in the first  10 years, and a first thinning 5 to 7 years later. Dominant trees are the  most stable ones, but also the most attractive for deer. To prevent damage, a  good wildlife management is necessary. By selecting the dominant trees and  following a consequent thinning, one creates a very uniform stand. This seems  to be the most mechanically stable, following the results of the research,  but it is known as ecologically dangerous.
Comparative study of C sequestration by new forests on former pasture lands
Authors: Lust N. , Van Camp N. , Muys B. , Nachtergale L.
Published: July 2016

The  research compares the C sequestration of on the one hand an old pasture and  on the other hand two young forest stands, planted on former pasture lands.  The stands are respectively ash and pin oak stands, planted 27 and 26 years  ago, with a basal area of 21.3 m2 and 13.10 m2.    C-content was assessed, based upon Hohenadl's model trees, for all  compartments. The total C-content of the pasture land presently amounts to  128 t/ha, whereas it reaches respectively 173 t/ha and 118 t/ha for the ash  and pin oak stands. The soils of the forest stands contain respectively 74  and 50 t carbon/ha. So, remarkable changes occurred in the C quantity and  allocation by the afforestation. Afforestation of a rich pasture leads in the  first phase to a noticeable decrease of the C content in the soil. The C  content of the A1 horizon is significantly greater in the pasture than in the  young forest stands.     Nevertheless afforestation of a pasture considerably increases, already  after 25 years, the C sequestration of the ecosystem, provided the used tree  species are suitable, i.e. they should be fast growing and produce a good  quality litter. This way, not only the aboveground C accumulation is useful,  but also the quantity and the quality of the soil humus. Research on the  evolution of the C sequestration after afforestation of agricultural lands  deserves priority.
Origin and development of the Flemish Forest Decree
Authors: Lust N.
Published: July 2016

The  Flemish forest decree of 13 June 1990 is the result of 15 years intensive  discussions and scrutiny by several concerned parties. The first draft was  mainly the work of a small forestry group, consisting of members of the  forest administration and the university. Afterwards this first draft has  been thoroughly scrutinized by different pressure groups: private forest  owners, local authorities, agricultural sector, nature conservation, rural  planning and politicians. Finally a decree, that can be considered as a  compromise, has been approved. In this decree the basic features of the first  draft are still present but the influence of the pressure groups is manifest,  especially from the nature conservationists and the agricultural lobby. Some  articles are also rather confuse, because of controversy between the pressure  groups.
Silviculture of Scots pine in Belgium
Authors: Lust N. , Geudens G.
Published: July 2016

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Biomass of understory species of Pinus halepensis Mill. forests in the Kassandra Peninsula - Chalkidiki
Authors: Smiris P. , Maris F. , Vitoris K. , Stamou N. , Ganatsas P.
Published: July 2016

This  study deals with the biomass estimation of the understory species of Pinus halepensis    forests in the Kassandra peninsula, Chalkidiki (North Greece). These  species are: Quercus    coccifera, Quercus ilex, Phillyrea media, Pistacia lentiscus, Arbutus  unedo, Erica arborea, Erica    manipuliflora, Smilax aspera, Cistus incanus, Cistus monspeliensis,  Fraxinus ornus. A sample of    30 shrubs per species was taken and the dry and fresh weights and the  moisture content of    every component of each species were measured, all of which were processed  for aboveground    biomass data. Then several regression equations were examined to determine  the key words.
Monitoring natural stand change in the forest reserve of Liedekerke, Flanders (Belgium)
Authors: Van den Meersschaut D. , De Cuyper B. , Vandekerkhove K. , Lust N.
Published: July 2016

Natural  stand changes in the forest reserve of Liedekerke were analysed during the  period    1986-1996, using a permanent grid of circular plots. The monitoring  concentrated on natural    changes in species composition, using stem number and basal area as  indicators, and changes    in spatial distribution and colonization capacities of trees and shrubs,  with special interest in the    competition between exotic and indigenous species. After only a decade of  monitoring important    natural changes in the woody layer were detected. The pioneer forest is  gradually maturing    through self-thinning processes and shifts in species composition. The  overall stem number    decreased with 33.6%, while the basal area increased with 20.9%. Birch (Betula pendula/    pubescens) and indigenous oak (Quercus robur/petraea) remained  dominant. More tolerant    exotic species, like red oak (Quercus rubra) and sweet chestnut (Castanea  sativa), are slowly    increasing their share in the species composition and expanding their  range. Pioneer species on    the other hand, like aspen (Populus tremula), willow (Salix  capreaicinerealaurita), alder buckthorn    (Frangula alnus) and  common (Alnus glutinosa)  and grey alder (A. incana),  strongly declined.    Black cherry (Prunus serotina) seems to be slowly invading the forest due to its  massive    natural regeneration. Strong competition may be expected especially from  rowan ash (Sorbus    aucuparia), which showed similar regeneration  and colonization capacities. Elder (Sambucus    nigra) dramatically extented its range, though  its share remains marginal. Beech remained absent    most probably due to the lack of mature trees in the vacinity of the  forest. Finally this    change detection allowed that general predictions could be made on the  future natural development    and composition of this forest reserve, which could serve forest management  decisions.
Challenges for the European higher education, with special reference to forestry
Authors: Lust N. , Nachtergale L.
Published: July 2016

The  ongoing discussion about the future of the forestry education can be  considered as a part of    the present intensive discussion on the European Higher Education System.  Both the Sorbonne and the Bologna declarations are calling for the harmonisation of the higher education systems in Europe. The reality, however, is that the existing structures show an extreme complexity and    diversity of curricular and degree structures, due to major differences in  several key factors. Forestry education in Europe reflects quite well the features of the Higher Education in Europe.    Curricula strongly differ, forestry as a science has thoroughly evolved  during the last decades,    foresters are faced to new challenges and the labour market offers other  opportunities. As a    result, there is both the need for harmonisation and for increased  mobility, meaning that there    are several reasons for changing forestry curricula. Fundamental changes in  the field of    profession and didactic requirements are major reasons to revise the  forestry curricula. The shift    from developing mainly the professional qualifications of the students to a  stronger emphasis on    the formation of the personal qualifications are considered as the main  general issue in the    changes of the forestry curricula.
Einfluss der Naturschutzgesetzgebung auf die Forstgesetzgebung in Flandern
Authors: Lust N. , Nachtergale L. , Serbruyns I.
Published: July 2016

Gegenstand  dieser Untersuchung ist der Einfluss der Naturschutzgesetzgebung auf  die    Forstgesetzgebung in Flandern. Von großer Bedeutung hierfür ist zunächst  das erste    Naturschutzgesetz von 1973. Die Forstverwaltung hat dieses grob vernachlässigt  und sah sich    mit den entsprechenden Konsequenzen konfrontiert. 1990 wurde das erste  Flämische Forstgesetz erlassen, in dem der ökologische Wert der Wälder bereits stark betont wurde. Das    Flämische Naturschutzgesetz von 1997 hat jedoch den Einfluss des  Naturschutzes auf den    Wald noch wesentlich verstärkt. Und schliesslich haben die Änderungen des  Flämischen    Waldgesetzes von 1999 die Ökologie noch stärker gewichtet.    Die allgemeinen Schlussfolgerungen bezüglich des Verhältnisses zwischen  Naturschutzgesetz    und Waldgesetz sind offensichtlich. Es gibt eine Reihe von Überlappungen  zwischen dem    Waldgesetz von 1990, revidiert im Jahre 1999, und dem Naturschutzgesetz von  1997. Durch    das Waldgesetz wird der Naturschutzwert des Waldes sehr stark betont. Der  Einfluss des    Naturschutzes auf die Forstpolitik, die Forstgesetzgebung und die  Waldbewirtschaftung ist groß.    Dabei kann das Naturschutzgesetz in Zukunft einen noch viel grösseren  Einfluss auf die    Waldbewirtschaftung ausüben. Durch die Naturschutzgesetzgebung gibt es  zahlreiche    Konfliktquellen zwischen dem Waldsektor und dem Naturschutzsektor. Sie  können zu einer    scharfen Auseinandersetzung zwischen beiden Gruppen führen, von der vor  allem die    Privatwaldbesitzer betroffen wären. Konflikte zwischen den Sektoren werden  unvermeidlich zu    einer Demotivation der Waldeigentümer und damit auch zu einem verminderten  Wert des    Waldbesitzes führen.
Impact of small-scale variability of soil pH on the vegetation composition in a mixed hardwood stand, East-Flanders Belgium
Authors: Zahedi GH. , Lust N. , Van Meirvenne M. , Nachtergale L. , Muys B.
Published: July 2016

1 Soil  pH of the forest stand varies widely for the different depths and is very  important in    determining the forest vegetation types. Main aim of the study was to  examine the    correspondence between forest vegetation composition and small-scale  heterogeneity in pH    by several statistical methods.    2 Ordination using DCA (Detrended Correspondence Analysis) found clear  distinction in the    vegetation structure and pointed pH differences as the main factor  explaining the variability    (Eigenvalue= 0.76 for the first three axis).    3 Clustering analysis by TWINSPAN resulted into four major vegetation  groups. Most of these    divisions were explained by differences in pH.    4 The spatial dependence of the pH at ectorganic and top mineral layers was  examined by    geostatistics analysis. All variograms showed a similar well-defined  structure. The structure    of variograms accounted for 95 - 100 % of the spatial dependence for the pH  at all depths.    All variograms represented the same range of 50 m for the pH at ectorganic  horizons, but the    distance of 65 and 72 m was calculated respectively for the pH at 0 - 5 and  5 -15 cm depth.    All variograms increased to the maximum lag over which they were  calculated.    5 The raster image of pH variability resulting from Kriging interpolation  coincided significantly    with the raster image of vegetation composition. It was concluded that it  is possible to predict    the pH value based on the vegetation composition or vice versa. Predicting  the vegetation    type from pH value is only possible for the range of the distance of the pH  variogram.
Structure and development patterns analysis of the Ostrya carpinifolia pure and mixed stands in the western part of Nestos valley
Authors: Milios E.
Published: July 2016

The  study was conducted in Ostrya carpinifolia (pure and mixed) stands in the slopes of the    western part of Nestos valley (in the region of Xanthi). In order to  analyze the structure and the    development patterns of our stands, 41 plots were established, trees were  cut, increment cores    were taken, and stem analysis was conducted in 3 couples of dominant  (competitive) trees. The    main results of this research indicate that a) O.  carpinifolia (pure and mixed) stands origin,    initiation, development patterns, structure and spatial distribution were  strongly affected by    anthropogenic disturbances. b) The development patterns and structures  (today) of O.    carpinifolia structural types were also affected  by three other important factors: the growth    ecology of each species, their regeneration mechanisms and the quality of  the site. c) O.    carpinifolia and F. ornus trees, until the age of 80  - 100 years old, dominate in the upper storeys,    exhibiting similar height growth patterns, whereas C. orienta lis trees usually are  stratified in the    lower storeys. d) The site sensitivity classification of the three main  species, in O. carpinifolia    mixed stands, is as follows O. carpinifolia > F. ornus > C. orientalis. This site sensitivity difference    between the main species of our mixed stands has a significant effect in  the formation of their    structure. We observe a gradual alteration of the species contribution, in  the total basal area of    the stand, in relation to site quality. e) O.  carpinifolia trees maintain a high sprouting  capacity in    medium ages (around 50 years old), whereas the most vigorous 30 years old  stump sprouts,    have high growth rhythms that are greater than those which had the seed  origin standards in    the first 30 years of their lives. f) The main silviculture objective is to  convert almost all stands in    seed origin stands. Furthermore, forest practice must favor multiple  species mixed stands. Their    composition must be determined in relation to site quality.
Dynamics and development patterns of Pinus sylvestris L. - Fagus sylvatica L. stands in Central Rhodope
Authors: Milios E.
Published: July 2016

The  study was conducted in second growth stands in the central Rhodope mountains  and    (specially) in the region of Xanthi. In order to determine the dynamics and  the development    patterns of Pinus sylvestris - Fagus sylvatica stands, 39 plots were established, trees were cut,    increment cores were taken, and stem analysis was conducted in 4 couples of  dominant    (competitive) pine and beech trees. The main results of this research  indicate that a) The    population structures, the regeneration and development patterns are  strongly influenced by    human and natural disturbances and species 'life history characteristics'.  b) The difference in    site quality between site types results in differences in the duration of  beech invasion (under pine) and in species basal area distribution. c) In good site qualities when individual dominant    beech and Scots pine (competitive) trees with a small age difference grew  together, the beech    trees, in some cases, have almost the same height growth as the pines and  the pine trees    showed a delayed (for the species) culmination in current annual volume  increment which is not    followed by a abrupt fall. d) The process of secondary succession is  influenced by disturbances    regime, environment, propagule availability and species biology.
The mixed forests of Greece
Authors: Zagas T. , Tsitsoni T. , Hatzistathis A.
Published: July 2016

Greece  is a mountainous Mediterranean country characterised by a variety of    microenvironments. As a result, a great number of mixed forest types  appear.    These stands are natural by unevenaged stands with a lot of ecological and  social advantages    (as resistance against biotic and abiotic factors) high biodiversity and  aesthetical beauty.    For this reason, these forests must be protected and managed in a  sustainable way, in order to    fulfil their valuable services.    This paper is dealing with the most important and representative  mixed-species stands of    Greece beginning from those existing in the lower elevations (zone of  evergreen broadleaves)    and continuing to the higher ones (zone of boreal conifers).
Die Tätigkeit des Flämischen hohen Forstrates
Authors: Lust N. , Nachtergale L. , Serbruyns I.
Published: July 2016

Die  Aufgaben des Flämischen Hohen Forstrates werden hauptsächlich durch das  Forstgesetz    bestimmt, teilweise auch durch das Naturschutzgesetz. Er soll nicht nur den  Minister und die    Forstverwaltung in der Forstpolitik beraten, sondern sich auch mit der  Behandlung des Waldes    in verwandten Politikbereichen beschäftigen.    Die Hälfte der Mitglieder müssen Waldbesitzer oder Vertreter von  Waldbesitzern sein.    Der Rat formuliert eine Vielzahl von Stellungnahmen. In den Jahren 1997,  1998 und 1999    standen die folgenden Themen im Vordergrund: das flämische Forstgesetz,  Kriterien für    nachhaltige Waldwirtschaft in Flandern, die langfristige  Forstwirtschaftsplanung und der    Aktionsplan Forstwirtschaft, das Naturschutzgesetz, die Raumordnung, das  Verhältnis zwischen    Naturschutz und Waldsektor, Bewirtschaftung von Privatwäldern,  Waldgruppierungen    (Zusammenschlüsse von Waldbesitzern), Erbschaftssteuer für Waldflächen und  die künftige    Waldpolitik.    Eine Evaluation des Rates ergab eine Reihe von Stärken und Schwächen. Die  Sitzungen des Rates finden sehr häufig statt. Er hat eine besondere Aufmerksamkeit für Berührungspunkte mit    verwandten Sektoren und Angelegenheiten. Trotz einer gewissen Dominanz  der    Privatwaldbesitzer sind die Stellungnahmen ziemlich ausgeglichen. Ein  besonders positiver    Punkt ist, dass er im hohen Mass zur Mitwirkung der Basis beigetragen hat.  Die Kapazität    innerhalb des Rates ist jedoch nicht immer ausreichend. Es zeigt sich, dass  der Minister und die    Forstverwaltung die Stellungnahmen des Rates nicht sehr hoch scnätzen. Der  direkte Einfluss des    Rates auf die Forstpolitik und auf die Politik von verwandten Sektoren ist eher  beschränkt.
Natural and artificial regeneration
Authors: Van Miegroet M.
Published: July 2016

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Az agrárpolitika hatása a föld árára
Authors: Bakucs Lajos Zoltán , Fertő Imre
Published: July 2016

A cikk az agrárpolitika a földárakra gyakorolt hatásával foglalkozik. Az empirikus tanulmányok és a közgazdasági modellek legfőbb eredménye, hogy az agrárpolitikai támogatások tőkésednek a földárakban,azonban ennek terjedelme meglehetősen széles intervallumban mozog. A mennyiségi szabályozással kombinált agrárpolitikai eszközök hatása a földárakra azonban kevésbé egyértelmű. A számítások aztmutatják, hogy föld árrugalmatlan, noha korántsem annyira, mint azt az elméleti modellek feltételezik. Az empirikus tanulmányok rávilágítottak arra, hogy a különböző agrárpolitikai programok hatásátkülön-külön kell becsülni, mert egyébként torzított eredményeket kaphatunk. A hedonikus regressziókon alapuló számítások azt sugallják, hogy a föld és a hozzá kapcsolódó változók térbeli sajátosságai szinténbefolyásolják a kormányzati programok hatását.

Journal of Economic Literature (JEL) kód: Q 15, Q 18
Kilépések politikája
Authors: Becskyné Nagy Patrícia
Published: July 2016

A tanulmány két részre tagolódik. Az első fejezetekben a szerző bemutatja a kockázatitőke-befektetésekből történő kilépések stratégiai jelentőségét, a kilépések módját és idejét befolyásoló tényezőket és a sikeres kiszállásokat elősegítő tevékenységeket. A tanulmány arra keresi a választ, hogy mik az egyes módozatok előnyei és hátrányai a tulajdonosok, a menedzserek és az adott cég számára. A második rész az exitek számának és értékének változásait tárja fel a 2000-től kezdődő időszakban Európában, hangsúlyt fektetve a közép-kelet-európai tendenciákra, külön kiemelve a magyarországi változásokat.

Journal of Economic Literature (JEL) kód: G24, G32
Az élhetőbb Magyarország esélye
Authors: Csaba Laszlo
Published: July 2016

A tanulmány azt a kérdést vizsgálja, hogy társadalmi értelemben mennyire volt sikeres Magyarország átalakulása az elmúlt két évtizedben. Megállapítja, hogy a gazdasági siker és a társadalmi deficit kettőssége mellett az első másfél évtized tartalékai kifulladóban vannak. Az uniós tagság csak esélyt, de nem biztosítékot jelent az új szakasz sikeres végbevitelére. 2007-ben jelentősen más kihívások előtt áll az ország, mint 1995-ben állt. Ebből is adódóan a fenntartható növekedés és az eddigieknél eredményesebb társadalompolitika kettősére, az ezt megalapozó irányok fölvázolására teszünk kísérletet.
Minőség az oktatásban
Authors: Polonyi Istvan
Published: July 2016

Az írás célja, hogy az oktatás minőségügyének alapkérdéseit oktatásgazdaságtani aspektusból megvizsgálja. Bevezetőnkben a minőséggel kapcsolatos alapvető koncepciókat tekintjük át, majd nemzetközi összehasonlító vizsgálatok, a PISA és az IALS felmérések eredményeinek bemutatásán keresztül vizsgáljuk a magyar felsőoktatás színvonalát. Megkíséreljük feltárni, milyen okokra vezethető vissza a hazai oktatás ezen felméréseken tapasztalható gyenge teljesítménye. Ezek után azokkal az oktatásban használatos minőségértékelésekkel, illetve azok indikátoraival foglalkozunk, amelyek széles körben elérhetőek, így elsősorban a nyilvános iskolai, illetve felsőoktatási rangsorok indikátorait tekintjük át. Végül pedig egy empirikus felmérés eredményein keresztül megkíséreljük feltárni, melyek a munkaadók felsőoktatással szembeni minőségelvárásai.
Protective effects of berberine on intestinal ischemia and reperfusion injury in rats
Authors: Chen Tanzhou , Lv Bin
Published: July 2016

This study aims to investigate the potential protective effects of berberine
on ischemia and reperfusion (IR) injury in rats. Thirty male rats were
randomly divided into three experimental groups as follows: the sham group,
the IR group and the berberine+IR group. Intestinal ischemia-reperfusion was
performed by occlusion of the superior mesenteric artery for 30 min, followed
by 2-h reperfusion. The berberine+IR group of rats were administered 200
mg/kg of berberine once a day for 7 days before laparotomy. Compared with the
IR group, rats pretreated with berberine prior to IR had significantly
reduced intestinal ischemia/reperfusion injury and a significant reduction in
Chiu?s score (p<0.05). The level of malondialdehyde and myeloperoxidase in
the berberine+IR group was significantly decreased compared with the IR group
(p<0.001). Superoxide dismutase activity in the berberine+IR group was
significantly higher than in the IR group (p<0.001). Compared with the IR
group, diamine oxidase was markedly decreased in the berberine+IR group
(p<0.01). The level of secretory immunoglobulin A in the berberine+IR group
was significantly increased when compared to the IR group (p<0.001). Our
results suggest that berberine can protect from intestinal IR injury and that
it can be beneficial in treating conditions associated with intestinal IR
injury.
Detection of Uniform and Nonuniform Differential Item Functioning by Item-Focused Trees
Authors: Berger Moritz , Tutz Gerhard
Published: July 2016

Detection of differential item functioning (DIF) by use of the logistic modeling approach has a long tradition. One big advantage of the approach is that it can be used to investigate nonuniform (NUDIF) as well as uniform DIF (UDIF). The classical approach allows one to detect DIF by distinguishing between multiple groups. We propose an alternative method that is a combination of recursive partitioning methods (or trees) and logistic regression methodology to detect UDIF and NUDIF in a nonparametric way. The output of the method are trees that visualize in a simple way the structure of DIF in an item showing which variables are interacting in which way when generating DIF. In addition, we consider a logistic regression method, in which DIF can be induced by a vector of covariates, which may include categorical but also continuous covariates. The methods are investigated in simulation studies and illustrated by two applications.
Evaluating Safety Benefits of the Insurance Corporation of British Columbia Road Improvement Program Using a Full Bayes Approach
Authors: Sayed Tarek , Sacchi Emanuele , deLeur Paul
Published: July 2016

The objective of this study was to conduct a time-series (before-to-after) evaluation of the safety performance of a sample of locations that have been improved under the Insurance Corporation of British Columbia (ICBC) Road Improvement Program. The program started in 1989 when ICBC established partnerships with local road authorities in British Columbia, Canada, and works cooperatively to make sound investments in road safety improvements. The overall effectiveness of the road improvement program was assessed by determining whether the frequency or severity of collisions at the improvement sites has been reduced after implementation of the improvement, and by quantifying the program costs versus the economic safety benefits to determine the return on ICBC’s road safety investment. Seventy-two urban intersections were included in the evaluation. The methodology adopted for estimating the safety benefits was a before–after study with the full Bayesian method, while the benefit–cost analysis was carried out by using two indicators: net present value and benefit–cost ratio (B/C) with a payback period of 5 years. Overall, the total reductions of severe (fatal plus injury) and nonsevere (property damage only) collision frequency for intersections with new pedestrian signal installations were found equal to −24.54% and −6.21%, respectively; −22.95% and −10.78%, respectively, for intersections with geometric design improvements; and −13.76% and −5.04%, respectively, for intersections with traffic signal upgrades. Finally, an overall B/C ratio of 4.32:1 was achieved.
Systemwide Impacts of Emergency Medical Services Resources on Freeway Crash Severity
Authors: Jung Soyoung , Qin Xiao , Oh Cheol
Published: July 2016

The objective of a study was to examine the systemwide effects of prehospital emergency medical services (EMS) resources quantitatively on crash outcomes throughout the entire South Korean freeway system. Latent class cluster and binomial probit regression models were combined to achieve this objective. In the cluster-based binomial probit regression, surrogate measures for prehospital EMS resources were obtained by combining medical service portals, freeway heliport maps, and freeway network log data in the crash data set. As a result, eight latent class clusters of crashes were determined on the basis of features associated with EMS resources, province, roadway, and traffic conditions at the scene of the crash. On-scene and recovery times were commonly significant in increasing the probability of fatal crashes in both entire groups and in each group of crashes, while the nearest ramp location and number of nearby EMS facilities significantly affected fatal crashes for a certain group of crashes. The findings provide meaningful insights that can enhance EMS training programs for initial medical aid and postcrash traffic management on all provincial freeways. Supplemental nearby EMS facilities and access points to them are needed particularly in South Korea’s southeastern and central province freeway sections, respectively. This research is the first data-driven study to assess systemwide EMS resources for the entire South Korean freeway system by using multiple data sources. It would contribute to informed decision making for future EMS provision.
Safety Culture: Examination of Safety Attitudes Across Transportation Modes
Authors: Hubbard Sarah
Published: July 2016

Transportation safety is a top priority for all agencies, although traffic fatalities remain a leading cause of death in many age groups. One traditional approach to safety is a multifaceted strategy that addresses the 4 E’s: education, enforcement, engineering, and emergency response. In recent years, some agencies have also undertaken collaborative initiatives such as Toward Zero Death programs in an effort to increase safety. Although roadway fatalities have decreased, there is still opportunity for improvement. Many research studies have identified factors that correlated with roadway crashes (e.g., geometric factors) and have documented the impact of mitigation measures, such as roadway improvements, policy changes (e.g., speed limits), and safety programs (e.g., distracted driving campaigns). Although crashes may be considered an unavoidable consequence of mobility, fatality rates vary dramatically by transportation mode, and the impressive safety record in aviation suggests that fatalities should not be considered inevitable. This research explores safety attitudes and practices for young adults in the aviation and roadway sectors, examines differences in safety training for roadways and aviation that may contribute to a positive safety culture, and identifies practices in aviation that may be beneficial in the roadway sector. In addition to providing a benchmark for the current safety culture and comparing attitudes and practices in the roadway and aviation environments, this research lays a foundation to develop best practices that will contribute to a positive safety culture, improve safety, and reduce the costs associated with roadway crashes.
Developing Australia’s Highway Safety Professionals: What Can the United States Learn?
Authors: Shaw John W. , Muir Carlyn , Johnston Ian , Noyce David A.
Published: July 2016

Highway safety is a complex issue that requires the combined skills of many different types of professionals, including engineers, public administrators, first responders, and public health officials. Although the United States and Australia are culturally similar countries with high levels of motor vehicle use, for historical reasons Australia has typically reached road safety milestones earlier than the United States has. Although a few American universities offer classes on road safety, current U.S. offerings predominantly consist of professional development short courses (often with a programmatic focus). In addition to professional development courses, some undergraduate and postgraduate courses in Australian universities offer electives on the principles of road safety engineering and methods for influencing road user behavior. This coursework can be viewed as part of a wider effort to implement scientifically validated methods and the safe system approach recommended by the International Transport Forum of the Organisation for Economic Co-operation and Development. Deeper integration of highway safety principles into the undergraduate curriculum could assist both countries’ students in developing the leadership skills necessary to achieve higher levels of safety performance.