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1.
The assessment of a forest resource in national inventories provides a firm basis for the calculation of biomass and carbon (C) stocks of forests. Biomass expansion factors (BEFs) and conversion factors provide a robust and simple method of converting from forest tree stem volume to total forest biomass. These factors should be constructed on the basis of nationally specific data in order to take account of regional differences in growth rates, management practices, etc. The objective of this study is to improve the accuracy of biomass estimation by calculating a range of age-dependant BEFs from representative data that more accurately describe the allometry of present forests. The results from this study show that the allocation of biomass to compartments in forest stands and throughout a rotation varies considerably, and that the use of BEFs for the calculation of C stocks in forests of sub-timber dimensions is highly impractical.
Brian TobinEmail:
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2.
Forests in north-eastern New South Wales have often been the focus of controversy. The tension between production and preservation continues and hampers current negotiations for a code of practice for private native forestry. The structure of many private forests reflects past mismanagement, and silvicultural intervention would benefit both conservation and production objectives, but such intervention is rarely financially viable. This paper sets out the economic and ecological basis for private native forestry. Both the timber industry and nature-based tourism are major contributors to the local economy, and both rely in part on private native forests. Draft regulations currently under negotiation do not offer incentives for improved private forest management.
V. Alex JayEmail:
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3.
The endozoochorous dispersal of vascular plant species by red deer (Cervus elaphus) was investigated in three forest areas of Schleswig-Holstein and Lower Saxony. The primary aim of this study was to determine of which plant species and in what numbers diaspores are dispersed by red deer, an animal with eminently large home ranges during a single day as well as over the year. A second aim was to examine the significance of endozoochory for plant species composition and diversity in forests. Special emphasis was placed on whether there are differences between the three study sites and in the course of the vegetation period. Freshly deposited faecal pellet groups were collected in the forests on five dates between May and November 2002 and viable seed content was determined by greenhouse germination (seedling emergence method). A total of 28,009 individuals representing 59 vascular plant species were detected in 220 dung samples. Red deer appears thus as an important vector for endozoochorous dispersal of plants. The number of seedlings found in the faecal pellets differs between plant species and research areas as well as in the course of the vegetation period. Dung seed content is largely dominated by one species, Urtica dioica. Grouping the species found in dung according to their habitat preference showed that mainly species that occur in forests as well as in open vegetation and non-forest species were dispersed endozoochorously, while species occurring mainly under a closed canopy were present in the excrements only in low numbers.
Goddert von OheimbEmail: Phone: +49-4131-782845Fax: +49-4131-782808
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4.
Commercial afforestation of agricultural land is often associated with social conflict over the perceived environmental, economic and social impacts of the plantations being established. One of the most common solutions suggested to this conflict is a shift from large-scale afforestation by companies and government agencies to small-scale afforestation by individual landholders. Small-scale afforestation by farmers is argued by many to have more positive and fewer negative impacts than large-scale afforestation by non-farmers. However, few studies have examined whether small-scale afforestation is associated with less social conflict than large-scale afforestation. This paper reports results of a recent study that compared afforestation conflicts in two regions: County Leitrim in the Republic of Ireland and the Great Southern region of Western Australia. Considerable afforestation has occurred in both regions in recent decades, and both have also experienced major shifts in the scale and ownership of the plantations being established over time. For both regions, establishment of small-scale farm forest plantations was found to be associated with considerably less social conflict than establishment of large-scale plantations by non-farmers. Some tentative explanations may be given for this pattern, based on comparisons between the two case study regions.
Jacki SchirmerEmail:
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5.
Interest in the incorporation of riparian buffers and forest farming were modeled following agricultural conservation and agroforestry adoption studies. Attitudes, individual characteristics, economic diversity of landowners’ household portfolio, and physical and ecological conditions were explanatory variables in Logit regression models of interest. Habitus and field, the values and institutions of farm operators, were included in the framework. Knowledge of the practice, perceived problems with the environment and attitude/habitus variables had a positive effect on the probability of being interested in riparian buffers. Knowledge of the practice was the most important factor in explaining interest in the case of forest farming, followed by attitudes about trees and concern for future generations, both habitus variables. Field variables like CRP payments representing familiarity with government programs that support conservation, had no significant effect on interest in riparian buffers. Older farmers were less interested in both practices, consistent with other findings. Existing economic diversification of the household portfolio had no effect on the probability of being interested in either practice.
Corinne ValdiviaEmail:
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6.
This paper analyses industrial round wood flows into, within, and out of Northwest regions of Russia. We examine sawlogs, pulpwood, and fuelwood used for industrial purposes obtained from logging, and chips obtained from the wood-processing industry. We attempt to clarify different recent trends in wood harvesting, industrial round wood export, and forest industries development that have an influence on unreported wood in Russia. Our method, which uses wood balance diagrams, provides an interpretation of data from different Russian sources in order to offer better transparency regarding wood flows from forests to mills. It also helps to explain the apparent imbalance between round wood supply and demand and it helps one to assess the possible share of unreported industrial round wood production in Northwest Russia. Based on annual forest-related statistical data available from the Ministry of Natural Resources, the State Committee of Statistics, and the Russian Federation’s Customs Department, unreported round wood flows can be estimated to be 23% of the total industrial round wood production, or approximately 9 million m3 u.b. per year. Unreported round wood flows are more common in export oriented regions that have poorly developed forest industries.
Yuri GerasimovEmail: Phone: +358-102-113253Fax: +358-102-113251
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7.
The aim of the study was to develop a stage-structured within-patch model describing predator-prey interactions of Cheyletus eruditus (Schrank) and Acarus siro L. on stored grain. Parameterisation of the model was done using data from the literature. Due to considerable variance in these data, statistical methods were used to extrapolate the parameters. The results of the simulations were compared with the experimental control of A. siro by C. eruditus on wheat. The results indicated that all life-history studies of A. siro yielded overestimated parameters leading to an unnaturally rapid population growth of A. siro on grain. The main reason seems to be the use of high quality food (wheat germs), which considerably increased fecundity. A new model with reduced fecundity was found to correspond well with the observed dynamics in a granary. The model of C. eruditus, including parameters from different sources, produced dynamics quite similar to the observed one. A simulation of biological control under laboratory conditions, on 45 g of wheat, showed that C. eruditus is able to control A. siro within the observed period. In contrast, simulation of the control in a granary showed a marked difference in comparison with the observed dynamics. The discrepancy is attributed to the effects of spatial factors, such as immigration. The predator-prey model developed here appears to be valid for the prediction of the local (within-patch) population dynamics of A. siro and C. eruditus on wheat grain at 20 °C and 80% RH.
Stano PekárEmail:
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8.
The state-level distribution of the size of family forest holdings in the contiguous United States was examined using data collected by the USDA Forest Service in 1993 and 2003. Regressions models were used to analyze the factors influencing the mean size and structural variation among states and between the two periods. Population density, percent of the population at least 65 years of age, percent of the population residing in urban areas, per capita income, income inequality, and per capita private forestland were found to be significantly correlated with the structure of landholding size. This paper suggests that the number and proportion of small-scale family forest owners in the United States are both increasing due to the increasing importance of non-timber amenities to forest landowners.
Y. ZhangEmail:
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9.
This article studies the possibility of using auctions as a policy instrument in conservation programs. In particular, it provides insight into the main concerns that need to be dealt with when implementing conservation auctions. To show the cost saving potential of this policy instrument, we also calculate the social welfare improvement that can be obtained for an afforestation project in Flanders. When developing conservation policies, it is thus worthwhile to consider auctions as an alternative policy instrument.
Sandra RousseauEmail:
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10.
The germination of common alder (Alnus glutinosa (L.) Gaertn.) and downey birch (Betula pubescens Ehrh.) seeds is often poor in bare-root nurseries. The effect of a variety of seed coverings and a few seed pretreatments on seedling emergence was examined in this study in an attempt to address this problem. Seeds of each species were sown in trays containing nursery soil, covered with grit, gravel, sand, combinations of these coverings, a hydromulch or a sealed plastic cloche and then incubated for 6 weeks at 17–20°C. The grit combined with sand or gravel, the hydromulch and the cloche increased seedling emergence when compared with the standard grit. In another experiment, seeds of each species were fully imbibed (FI) (>50% moisture content, MC), as per standard practice, or adjusted to target MC (TMC) (30–35% MC) levels, and then chilled to release dormancy. Some seeds of each MC treatment were primed at 20°C for 2 days following chilling, after which all seeds were evaluated in laboratory tests and a nursery trial. Germination potential of the FI seeds declined in the lab tests by the second test date, which was reflected in low seedling emergence in the nursery in birch. The primed FI seeds of alder germinated most rapidly in the nursery, but other effects were not significant. Seedling emergence was better in the nursery in response to the TMC than the FI pretreatment in birch.
Conor O’ReillyEmail:
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11.
The domestication of non-timber forest species (NTFS) is receiving increasing attention from developing economies. However, little is known about the selection of NTFS in Nepal for commercial uses. Sixteen selection criteria were developed and NTFS were ranked for community and private plantations in both low altitude and high altitude areas of Makawanpur district, Nepal, by workshops of multiple NTFS stakeholders. The rigorous scoring of 12 ecologically screened NTFS against the 16 selection criteria revealed that kurilo and sarpagandh are highly preferred NTFS for low altitude areas whereas chiraito and jatamanshi are highly preferred for high altitude. This finding coincides with the general perception of participants and contemporary literature. These are the species being rapidly depleted from the natural forests. Rapid decline of valuable species creates strong motivation from stakeholders for planting them on community and private land.
Tek N. MaraseniEmail:
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12.
The effects of stocking on wood stiffness (MoE) for three Eucalyptus species are quantified using a 6-year-old trial established in New South Wales, Australia. An acoustic time-of-flight tool measured the velocity between two probes in the outerwood, from which the stiffness was estimated. Four stocking levels (714, 1,250, 1,667 and 3,333 sph) were examined. Stiffness varied significantly between all species, with E. cloeziana showing the highest stiffness (14.2–15.7 GPa), followed by E. pilularis (12.2–13.5 GPa) and E. dunnii (10.7–12.6 GPa). There was a stiffness increase (around 11%) between 714 and 1,250 stems/ha for all species but thereafter differences between stockings were not always significant. Trees were also assessed for basic density, dbh, total height, crown area, green crown height and stem slenderness (height/dbh). Only stem slenderness had a significant association (0.41 ± 0.17) with stiffness. These findings suggest that, where stiffness is a priority, forest managers could reduce establishment costs with low stockings (around 1,250 stems/ha).
Luis Alejandro ApiolazaEmail:
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13.
How to foster good husbandry of private native forests   总被引：2，自引：2，他引：0  
It is generally agreed that effective conservation requires the cooperation of private landholders to complement reserve-based efforts, but there is little agreement about how this can best be achieved. Various stakeholders lobby for tough regulations, for greater landholder freedom, and for incentives for activities or outcomes. A review of these alternatives suggests an emerging consensus that incentives are the most effective approach. Policy-makers should consider incentive-based approaches such as stewardship support to foster conservation outcomes on private lands.
Jerome K. VanclayEmail:
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14.
The practical application of the orientation distribution function (ODF), being the three-dimensional representation of the texture function, was presented. The investigations of the crystallograpically organized regions of wood were performed. The experimental methods of the X-ray diffraction were discussed in detail. The incomplete pole figures were measured in order to calculate the ODF. The dominant components of the crystallographical texture of wood were determined from the obtained ODF. The obtained texture function was also used to derive the complete pole figures, additional non-measurable figures as well as inverse pole figures. The figures were used to perform additional analysis of the crystallographical organization. The traditional concept of the microfibril angle was enhanced by defining two transformation parameters, i.e. a crystallographical axis and an angle of rotation.
Wiesław OlekEmail:
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15.
This study assessed the influence of various operational transplanting procedures on J-rooting compared to a no transplanting approach of direct sowing into Hiko trays. Eucalyptus dunnii Maiden and E. pilularis Smith seedlings were examined. All transplanting treatments increased severity and incidence of J-rooting for both species. Gently loosening seedling plugs by hand prior to their removal from cells of 512 trays and gentle manual production of seedling planting holes (dibbering) in potting media in Hiko cells, rather than mechanically loosening and mechanical dibbering, reduced the incidence of J-rooting for both species. Disturbance of seedling plugs from mechanized loosening and increased compaction from mechanical dibbering are believed to have a negative effect on root development. Direct sowing produced seedlings with highest root quality when measured at 27 weeks.
Dane S. ThomasEmail:
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16.
The article, in relation to the importance of canopy cover as stand density and biodiversity indicator, describes the main related field measurement techniques. In particular the authors emphasize the distinction between canopy cover and canopy closure when forest cover is usually measured through the current techniques. After a conceptual clarification the study focuses on the comparison of three ground-based canopy cover estimation techniques and two ground-based canopy closure estimation techniques, analyzing the data collected in a test carried out on Alpine stands. As expected, the results indicate that some techniques [GRS densiometer, visual estimation and hemispherical photographs (HP) assessed with a narrow angle of view] are more suitable to measure canopy cover, while others (spherical densiometer and HP with a wide angle of view) are more adapted to estimate canopy closure. In general, the techniques that use a wide angle of view tend to overestimate the canopy cover.
Alessandro PalettoEmail:
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17.
The behaviour of air-dried and fully saturated parallel strand lumber (PSL) was determined under both static and impact loading. It was found that the moisture content had a significant effect on peak stress and deformation, stress rate, time to failure, and fracture energy. In addition, the results from this study were combined with those from previous studies in order to obtain a more general relationship between strength and stress rate for air-dried PSL.
Sidney MindessEmail: Phone: +1-604-8224471Fax: +1-604-8226901
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18.
Forest owner cooperations (FOC) are bundling wood supply from small-scale forests and some also offer additional services, such as wood harvesting or planting. FOCs are growing throughout Europe in terms of the managed timber volume. The increasing timber demand of forest-based industries as well as the new, rapidly growing demand for energy plants could lead to an under-supply in the following years in Europe. Because of high harvesting arrears in small-scale forests, FOCs are seen as an opportunity to overcome this foreseen timber shortage. The paper maps out timber mobilisation strategies using the SWOT (Strengths, Weaknesses, Opportunities and Threats) approach.
Peter RauchEmail:
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19.
This research utilises a contingent behaviour valuation technique to value a number of improvements to recreational facilities in small-scale forests in Ireland. Willingness-to-pay estimates have previously been made for Coillte (Ireland’s state-owned forestry company) trails and forests. The total non-market value of Irish forests has also been examined. This paper adds to the literature by being the first to estimate the consumer surplus associated with recreational enhancements to Irish small-scale forest resources. The results presented indicate that community owned small-scale forestry can contribute enormously to the wellbeing of nearby urban residents, through the provision of outdoor recreational services.
Stephen HynesEmail:
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20.
This paper examines the trade-offs between woodland management for timber and public good outputs in English woodlands. Recent evidence suggests that some public good values may be declining as a result of a lack of woodland management. Such under-management has been attributed to the decline in timber values and reduction in the productivity of woodlands and forests for timber products. It is argued that assessing the management needs of woodlands in order to enhance public good outputs presents a complex challenge and often depends on a variety of factors, including location, type of woodland, age, condition, substitutability and ownership motivation. However, in most instances a moderate level of management (whether for timber or otherwise) is likely to be beneficial for public good outputs.
Julie UrquhartEmail:
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