Search

Worldwide, medicinal and aromatic plants play an important role for humanity. Thousands of medicinal plants are used across the world. Almost 300 medicinal plants are known and used in Romania. Their distribution is not uniform across the country, being depended in some cases of the presence of forest sites. The main goal of this paper was to estimate the maximum quantities of medicinal plants that could be harvested by the eight Forestry Directorates, managed by National Forest Administration Romsilva, from the eastern part of Romania. Several studies, papers, indicators and databases were taken into account. 38 medicinal plant species have potential in terms of harvesting in the Eastern Romania, with a total estimated quantity of more than 1.500 tons. The highest quantities could be harvested by Vaslui, Iași, Vrancea and Botoșani Forestry Directorates. The species with the highest potential were: bear's garlic, silver linden, elder, small-leaved lime, common nettle, large-leaved linden and common hawthorn. Harvesting and management measures aimed at protecting certain medicinal plant species were also proposed. [ABSTRACT FROM AUTHOR]

This paper initially reviews the occurrence of clones in nature, through geological history to the present day. Studies of the current natural population structure of Picea abies are reviewed as a background to assessing the ecological threats associated with somatic embryogenesis (SE) of the major commercial tree in Scandinavia. These threats are judged as most likely to result from (a) loss of genetic diversity, (b) loss of adaptation of tree populations, and (c) changes in other components of the ecosystem due to genetic changes of the dominant forest tree. Particular attention is given to the potential effects of SE on altered risk of impact from biotic damaging agents and effects on other species. The potential effects of SE on ecosystem services are discussed. The chapter ends with management recommendations. [ABSTRACT FROM AUTHOR]

Abstract Spatial pattern analysis is useful to elucidate the type and importance of the ecological processes in forest ecosystem. To better understand the dynamics of the natural secondary forest ecosystem and to provide information regarding the interactions between arbors and shrubs, the spatial patterns of dominant species in a natural secondary forest was examined in this paper. We developed a 2 ha secondary forest plot by mapping the location of all woody plants (diameter at breast height ≥1 cm). Univariate and bivariate Ripley's L(r) functions were utilized to evaluate the spatial patterns and association of the three dominant plants (P. davidiana , B. platyphylla and C. mandshurica). It was found that aggregated distribution was the main pattern in the dominant populations of the total and size-specific individuals of arbors at most scale. The degree of aggregation gradually decreased with size in B. platyphylla due to self-thinning while increased in P. davidiana which may attribute to the effects of logging for large- and medium-size woods in 1940s or 50s. In associations of intra-/interspecies pairs, positive association was the majority of intraspecies, whereas negative association was the domination in interspecies. Remarkable, mutual independence dominated in C. mandshurica vs. size-specific B. platyphylla pairs at most scales, and positive association emerged at greater than 8 m scales in C. mandshurica vs. size-specific B. platyphylla- large, may contribute to different niche occupying that generated less competitions for resources, even the large ones could provide preferable shelter for shrubs. [ABSTRACT FROM AUTHOR]

The Amazon contains some of the most critical ecosystems on earth and Igapó forests are one of those ecosystems. They are flooded by “black-water”, leached runoff of forest litter. To help in our understanding of igapó forests, and to act as a resource for their future research, I review what we know about their composition and structure. I used my own sampling data to construct floristics tables of the tree species, and tables of physical structural parameters such as tree density, species richness basal area and above-ground biomass (AGB). In addition I used data gotten from literature searches on google scholar, biosys, WorldCat discovery services and other databases for all papers that sampled trees in plots within igapó forests. I found there was a total of 59 families sampled in all the plots. The families with the most genera were Fabaceae and Caesalpiniaceae, with the most species were Fabaceae and Euphorbiaceae, and with the most tree stems were Fabaceae and Euphorbiaceae. The most common genera were Mouriri and Lincania and the most common species were Virola elongate and Swartzia polyphylla. For structure, total stems had a wide range between 167 and 683 per ha, stem sizes generally conformed to a “reverse J” distribution pattern, mean stem sizes were ~20 cm diameter at breast height, there was a species richness range between 90 and 119 per ha, and igapó forests were more open than other forest-types in the Amazon basin. While these plots were in primary igapó forest, my samplings of secondary igapó forests showed they had a reduced structure compared to primary igapó forests but were similar within the different kinds of secondary igapó forests. [ABSTRACT FROM AUTHOR]

The paper investigates how different hierarchy structuring in analytic hierarchy process (AHP) may affect the final results in the decision-making process. This problem is analyzed in a case study of the Rila monastery forest stands in Bulgaria. There were three similar and mutually overlapped hierarchies defined. A decision maker evaluated all of them and after analyzing final results and consistency performance, he selected and revised the most appropriate hierarchy structure. Consistency check assisted in detecting the judgments which have strongly violated evaluation procedure. These mistakes are interpreted as a consequence of a large number of required pair-wise comparisons. The paper emphases the importance of properly defining hierarchy structure and recommends using consistency analysis as a guide and not as a directive for the revision of judgments. [ABSTRACT FROM AUTHOR]

It is a well-known fact that the West part of Romania presents good climatic-edaphic conditions for the ecological requests of Turkey oak (Quercus cerris) and Hungarian oak (Quercus frainetto). As such, the two species offer large productions and good quality of wood. The present paper intends to analyze only the forests that belong to the hill Turkey oak - Hungarian oak stands of superior productivity types, namely 7 forest management units from 3 production units from the forest district. The main purpose of this paper is to prepare stational datasheets for these forests with a focus on the characteristics of stagnoluvosols on which these species grow in correlation with their requests. After a presentation of the climatic conditions, the edaphic conditions were studied and soil profiles were situated in each forest management plan. Samples were then gathered and analyzed. Further analyses were realized for 4 forest management plans in order to establish the potential trophicity. Ecological factors and determiners were also analyzed and were then framed on size and species favorability categories. The ecological datasheet contains the size categories and favorability categories for all the ecological factors. Their synergetic effects have as result a superior quality type of station. Even though the luvosols are considered soils with a lower trophicity, some qualities of the studied soils (such as the large physiological thickness, the very large edaphic volume, the humus percentage and distribution on horizons, the high content of total nitrogen) lead to a potentially high trophicity. [ABSTRACT FROM AUTHOR]

Wildfires are a widespread phenomenon in Mediterranean environments. Wildfires result in different fire severities, and then in contrasting plant cover and floristic composition. This paper analyses the recovery of the vegetation eighteen years after a wildfire in Catalonia. The Pinus pinaster ssp. forest was affected by three different severities in July 1994, and studied the spring of 1995 and again in 2008. After eighteen years (2012), our research found that burnt sites constitute a dense forest with a broad variety of species, including many young pines, shrubs and herbaceous plants, but that the risk of fire remains very high, due to the large quantity of fuel and the flammability of the species. The management of the post-fire is critical when high severity fires take places, and it is recommended that high-severity fires must be avoided for a sustainable forest management. We recommend that once the timber ( Pinus plantations) production is not profitable, Quercus suber L. and Pinus pinaster ssp. forest should be promoted, and pine plantations avoided. [ABSTRACT FROM AUTHOR]

Novel ecosystems occur when new combinations of species appear within a particular biome. They typically result from direct human activity, environmental change, or the impacts of introduced species. In this paper, we argue that considering commercial tree plantations as novel ecosystems has the potential to help policy makers, resource managers, and conservation biologists better deal with the challenges and opportunities associated with managing plantations for multiple purposes at both the stand and landscape scales. We outline five inter-related issues associated with managing tree plantations, which are arguably the largest form of terrestrial novel ecosystem worldwide. This is to ensure that these areas contribute significantly to critical ecosystem services, including biodiversity conservation, in addition to their wood production role. We suggest that viewing tree plantations as novel socioecological systems may free managers from a narrow stand-based perspective and having to compare them with natural forest stands. This can help promote the development of management principles that better integrate plantations into the larger landscape so that their benefits are maximized and their potential negative ecological effects are minimized. [ABSTRACT FROM AUTHOR]

Mexican temperate forests, at the southernmost end of the distribution range of this ecosystem, are the world's centre of diversity of pine and oak, with 55 and 161 species, respectively. Such forests are threatened by land-use change, unsustainable forest management practices, and climate change; these threats reduce their diversity, alter the distribution ranges of species, modify disturbance regimes, and reduce ecosystem adaptability. This paper briefly reviews ( i) the ecology of the Mexican temperate forests, ( ii) the ecological basis for the unique diversity of pine and oak species, ( iii) the main disturbances as well as the main drivers of global changes affecting these forests, in particular climate change, and ( iv) the social, economic, and cultural factors to be considered in proposing a new forest management approach. It proposes a new conceptual framework to manage Mexican temperate forests that are in line with ( i) their natural dynamics, ( ii) the rapidly changing and uncertain global environmental, social, and economic conditions, and ( iii) the complex adaptive system approach. This new forest management combines functional zoning, multispecies plantations, and sylvicultural interventions to increase the adaptive capacity of forests as a way to balance the increasing need for timber products with the need for other ecosystem services facing rapidly changing and uncertain future environmental, social, and economic conditions. [ABSTRACT FROM AUTHOR]

The uniform angle index (UAI) is used to characterize the spatial distribution of a forest community or of individual tree species within that community. This study presents an empirical assessment of the performance of a new statistical test used in conjunction with the UAI. In this study, the UAI is applied to observed and simulated communities. The effect of plot size and density are examined and the results are compared with the criteria of the aggregation index R of Clark and Evan (CE-R) and Ripley's L function (RL). The results suggest that the UAI performs well in determining a particular class of spatial pattern and that, in contrast to the CE-R index, it is unaffected by population density because the standard deviation can be estimated when the density is known using a new empirical relationship presented in this paper. The results of this study represent an improvement in the development of the UAI, verifying its performance and confirming its overall utility. Our comparative analysis positions the UAI among its historical competitors, the CE-R and RL criteria. The UAI index, which does not require expensive mapping of tree positions, can produce results that are equivalent to those obtained by RL and more robust and reliable than those obtained by CE-R. [ABSTRACT FROM AUTHOR]

Korean pine ( Pinus koraiensis ) is an important species of forests in Northeast China and the Russian Far East. In recent years, human disturbances have increasingly threatened the long-term population sustainability of Korean pine in Northeast China. Though the Chinese government has implemented various programs to restore and protect Korean pine, results have not been satisfactory. Economic income often conflicts with ecosystem function, so figuring out ways to balance ecologic and economic values is important for Korean pine sustainability and management. The effects of humans on Korean pine forest are complex and interact in ways that are difficult to predict at the landscape scale. In this paper, we used a simulation approach to examine multiple intensities of timber harvest and seed harvest on landscape-scale Korean pine coverage and age structure. We found that the influences of seed harvest became increasingly important over the simulation period. Seed harvest noticeably influenced the percent coverage of young (<60 yr) Korean pine. Young age classes of Korean pine disappeared when seed harvest intensity was high, even with a low timber harvest intensity. Except during high timber harvest intensities, Korean pine maintained its coverage and age structure to a certain extent under a medium seed harvest level. When seed harvest was prohibited, Korean pine coverage remained steady compared to initial conditions, regardless of the timber harvest intensity. Percent coverage of young and middle age (60–120 yr) Korean pine increased late in the simulation period. Our study showed that some level of seed harvest intensity combined with medium and low timber harvest intensities may be optimal for managers to maintain a viable economy together with ecosystem sustainability. [ABSTRACT FROM AUTHOR]