Search

Sacred natural sites (SNS) are instances of biocultural landscapes protected for spiritual motives. These sites frequently host important biological values in areas of Asia and Africa, where traditional resource management is still upheld by local communities. In contrast, the biodiversity value of SNS has hardly been quantitatively tested in Western contexts, where customs and traditions have relatively lost importance due to modernization and secularization. To assess whether SNS in Western contexts retain value for biodiversity, we studied plant species composition at 30 SNS in Central Italy and compared them with a paired set of similar but not sacred reference sites. We demonstrate that SNS are important for conserving stands of large trees and habitat heterogeneity across different land-cover types. Further, SNS harbor higher plant species richness and a more valuable plant species pool, and significantly contribute to diversity at the landscape scale. We suggest that these patterns are related not only to pre-existent features, but also to traditional management. Conservation of SNS should take into account these specificities, and their cultural as well as biological values, by supporting the continuation of traditional management practices.

Old-growth forests have a primary environmental and ecological value, as they closely recall primeval forests and the natural forest landscape that was spread throughout Italy and Europe before man intervention heavily altered the functioning of most natural ecosystems. These ecosystems are more and more recognized as keystones of environmental policies (i.e., the EU Biodiversity Strategy 2030) aimed to preserve biodiversity and mitigate the impacts of climate change. A recent report highlights that Europe's old-growth forests account for only 3 percent of the overall forest surface. The majority of italian old-growth forests are located along the Apennines, especially in the Pollino, Sila and Aspromonte National Parks, in remote montane areas characterized by irregular topographical conditions (i.e., high slopes and/or shallow soils) which hamper the access and exploitation of these less productive stands, thus allowing the survival of old-growth forests for many centuries. The ongoing climate change is a significant challenge to the conservation of old-growth forests, particularly in areas such as the Mediterranean basin, where an intensification of extreme climate events is expected. Heat waves can exacerbate drought's negative impacts on tree growth and survival, leading to reduced woody carbon stocks and biodiversity in old-growth forests. To date, there is poor understanding of such highly valuable and extremely fragile natural ecosystems in Italy. Insights are available based on data gathered as part of two research programs, funded by the Italian Ministry of the Environment and Land and Sea Protection, with the purpose of creating a Network of Old Growth Forests in Italy's National Parks. In this study, we aimed to highlight the role and importance of old-growth forests, focusing on those located within the Pollino National Park. A comprehensive overview of the key strengths and weaknesses, that mark these peculiar forest ecosystems, was followed by a discussion of the future outlook, grounded on strategies that will ensure not only the protection and conservation of these ecosystems, but also their development and promotion. [ABSTRACT FROM AUTHOR]

The Tongass National Forest in southeast Alaska, USA, includes the Alexander Archipelago and narrow North American mainland, comprising one of the largest remaining, largely pristine, coastal temperate rainforest in the world. Management of the Tongass has become increasingly challenging because of expectations of a conservation framework designed to maintain viable populations of native wildlife species while decades of extensive clearcut logging of old‐growth forests has continued. We used the findings of multiple published studies conducted on the Tongass from 1998 to 2017 to examine 4 assumptions of its wildlife conservation strategy (WCS): forest planning assessments of wildlife viability were realistic, forest management and conservation policies are implemented at appropriate ecological scales, old‐growth reserves are effective habitat conservation areas and ensure functional connectivity, and forest‐wide standards and guidelines ensure sufficient habitat for sensitive species in managed landscapes. Several ecological field studies, population and spatial analyses and modeling, and statistical analyses revealed that wildlife viability assessments to evaluate forest plan alternatives underestimated the risk of extinction by only examining individual vulnerable species rather than considering joint probabilities across multiple species; the ecological scale of management and conservation policies do not adequately consider area‐sensitive vulnerabilities of island communities as evidenced by the increasing risk of extirpation of island endemics whose populations have become isolated and reduced; old‐growth reserves are unlikely to maintain viable populations of endemic small mammals in isolation or as functionally connected metapopulations; and a spatially explicit analysis of individual home ranges demonstrated that forest‐wide standards and guidelines provide about half the breeding habitat needed by a federally listed endemic raptor, the Queen Charlotte goshawk (Accipiter gentilis laingi), of which only half of that is secure. Thus, assertions that the WCS is properly functioning as designed are dubious because a comprehensive monitoring plan has not been implemented and vital underlying assumptions are not supported by available science. We recommend 3 forest management and conservation policy adjustments: limit size and location old‐growth forest harvests, restore forests through intermediate stand management of second growth, and conduct a formal review of WCS elements and assumptions. [ABSTRACT FROM AUTHOR]

Old-growth forests have a primary environmental and ecological value, as they closely recall primeval forests and the natural forest landscape that was spread throughout Italy and Europe before man intervention heavily altered the functioning of most natural ecosystems. These ecosystems are more and more recognized as keystones of environmental policies (i.e., the EU Biodiversity Strategy 2030) aimed to preserve biodiversity and mitigate the impacts of climate change. A recent report highlights that Europe’s old-growth forests account for only 3 percent of the overall forest surface. The majority of italian old-growth forests are located along the Apennines, especially in the Pollino, Sila and Aspromonte National Parks, in remote montane areas characterized by irregular topographical conditions (i.e., high slopes and/or shallow soils) which hamper the access and exploitation of these less productive stands, thus allowing the survival of old-growth forests for many centuries. The ongoing climate change is a significant challenge to the conservation of old-growth forests, particularly in areas such as the Mediterranean basin, where an intensification of extreme climate events is expected. Heat waves can exacerbate drought’s negative impacts on tree growth and survival, leading to reduced woody carbon stocks and biodiversity in old-growth forests. To date, there is poor understanding of such highly valuable and extremely fragile natural ecosystems in Italy. Insights are available based on data gathered as part of two research programs, funded by the Italian Ministry of the Environment and Land and Sea Protection, with the purpose of creating a Network of Old Growth Forests in Italy’s National Parks. In this study, we aimed to highlight the role and importance of old-growth forests, focusing on those located within the Pollino National Park. A comprehensive overview of the key strengths and weaknesses, that mark these peculiar forest ecosystems, was followed by a discussion of the future outlook, grounded on strategies that will ensure not only the protection and conservation of these ecosystems, but also their development and promotion.

The EU Biodiversity Strategy 2030 (EUBDS) aims to preserve and restore biodiversity by protecting large areas in the EU. An extensive part of these protected areas will presumably be covered by forests. This study analyses the economic effects of EUBDS implementation on German forestry in two scenarios, based on different possible interpretations of the EUBDS' key commitments, using a forest economic simulation model. A special focus is placed on the opportunity costs of coarse wood debris (CWD). Over a simulated 200-year period, a decrease in timber harvest of 13% and 44% is estimated under the respective scenario assumptions. This leads to a reduction in the silvicultural contribution margin (SCM) of on average 0.25 B EUR a−1 (14%) and 0.79 B EUR a−1 (45%). In terms of the total SCM, protected forests contribute 35% and 15% in the two scenarios. The accumulation and preservation of CWD incurs a substantial loss of utility, as 15% and 19% of annual logging is required for conservation purposes. However, the EUBDS may also provide economically tangible benefits. A rational decision would be to implement a scenario if the "net benefit" from the protected status exceeds the losses from set-aside and conservation requirements. [ABSTRACT FROM AUTHOR]

It is desirable to update scientific knowledge on key aspects of forest biodiversity protection and implement it more effectively into forestry practice. A review was prepared across the Web of Science Core Collection database, searching in the “Topic” section, using a key words string: ((biodiversity OR „biological diversity“) AND („forest management“ OR forestry) AND „central Europe“). Particular attention should be paid to ending the clear-cutting and monocultures cultivation, as the most significant forms of intensive management. It is necessary to focus on the restoration of a varied tree species composition with respect for succession, the protection of old-growth forest habitats and their structures, as well as the restoration of open forests and the renewal of historical management forms (e.g. coppicing and forest grazing). In the interest of biodiversity, a combination of integrative and segregative management can be highly recommended. Reserves are essential as habitats for the most endangered species, but their role must be supported and complemented by integrative management in commercial forests. Such integrative management should emulate natural disturbances regime, predominantly with mixed severity. [ABSTRACT FROM AUTHOR]

We present a data set resulting from the first round of a national monitoring program of forest reserves. It contains 9538 permanent plots, distributed across 111 study sites in mainland France (including Corsica). Notably focusing on dead wood measurement, this protocol has primarily been applied in strict forest reserves and special nature reserves (sensu Bollmann & Braunisch 2013), with 68% (6494) of the plots being currently located in strict forest reserves (unmanaged) and 24.7% (2363 plots) in forests unmanaged for at least 50 years. Sites cover a large variety of ecological conditions, from lowland to subalpine forests, but with an underrepresentation of Mediterranean forests (Table 1). The protocol assesses all the stages of a tree's life cycle, from seedling to decomposed lying dead wood. On each plot, a combination of three sampling techniques was used: (1) fixed‐area inventory for regeneration, standing dead trees, living trees, and coarse woody debris (CWD) with diameter over 30 cm; (2) transect lines for CWD with diameter <30 cm; and (3) fixed‐angle plot method for living trees with diameter at breast height (DBH) >30 cm (using a relascopic angle of 3%). Measurements include exact tree location (azimuth, distance), species, diameter(s), tree‐related microhabitats, decay stage and bark cover, and seedling cover. With ongoing climate change, the program network can also provide important information to monitor changes in forest ecosystems. It can also be used as forest management monitoring or conservation status assessment. These data are freely available for noncommercial scientific use (Creative Commons Attribution 4.0 CC BY SA 4.0) with attribution, and this paper must be cited if this material is reused. [ABSTRACT FROM AUTHOR]

A campaign is underway to clear established forests and expand early-successional habitats—also called young forest, pre-forest, early seral, or open habitats—with the intention of benefitting specific species. Coordinated by federal and state wildlife agencies, and funded with public money, public land managers work closely with hunting and forestry interests, conservation organizations, land trusts, and private landowners toward this goal. While forest-clearing has become a major focus in the Northeast and Upper Great Lakes regions of the U.S., far less attention is given to protecting and recovering old-forest ecosystems, the dominant land cover in these regions before European settlement. Herein we provide a discussion of early-successional habitat programs and policies in terms of their origins, in the context of historical baselines, with respect to species’ ranges and abundance, and as they relate to carbon accumulation and ecosystem integrity. Taken together, and in the face of urgent global crises in climate, biodiversity, and human health, we conclude that public land forest and wildlife management programs must be reevaluated to balance the prioritization and funding of early-successional habitat with strong and lasting protection for old-growth and mature forests, and, going forward, must ensure far more robust, unbiased, and ongoing monitoring and evaluation.

Old-growth forests are considered a benchmark for naturalness and models to which one compares managed forests, comparison leading to debates around biodiversity and its conservation, structure and dynamics, polarizing conservationists and forest practitioners. Plant pathogens are frequently disregarded as components of forests biodiversity, the common perception referring to this category of organisms as important biotic stressors. However, pathogens building several functional groups (necrotrophic and biotrophic pathogens, endophytic pathogens, sapro-parasitic species, generally on wood), in highly natural forests such as old-growth forests are establishing interaction networks with several other functional groups of organisms such as hyperparasites, consumers, disease facilitators, indirect opportunistic species (such as tree hollow dwellers), saprotrophs or mutualists. Being connected to old trees (rare or missing components of managed forests) or to endangered forest plants, pathogens become indicators of naturalness and biodiversity. The gradient going from saprotrophs, to sapro-pathogens and generalist/specialist pathogens characterizing forest ecosystems is linked at great extent to wood and bark, being connected to nutrient cycling as ecosystem level process. As long as disease is maintained within the baseline mortality of the trees, pathogens play the important role of control factors and contribute directly and indirectly to forest biodiversity. The current disease ecology progresses, the biodiversity integrative studies, and the new holistic approaches shaping modern ecology bring in the focus rare, endemic pathogens as important control factors of plant populations, as components of the plants’ phenotypic niche and of the global biodiversity, as potential providers of services (sources of medicines) and components of the intricate ecological webs. However, the comparisons between old-growth and managed forests biodiversity should be focused on species evenness (high evenness in old-growth forests versus low evenness in managed forests) and not particularly on species richness. Still, there are pathogens responsible for major biotic disturbances in forests worldwide, the invasive, alien or emerging pathogens threatening both old-growth forests and managed forests.

Old-growth forests are considered a benchmark for naturalness and models to which one compares managed forests. The comparison led to debates around biodiversity and its conservation, structure and dynamics, polarizing conservationists and forest practitioners. Plant pathogens are frequently disregarded as components of forests biodiversity, the common perception referring to this category of organisms as important biotic stressors. However, pathogens are building several functional groups such as necrotrophic and biotrophic pathogens, endophytic pathogens, sapro-parasitic species, in highly natural forests including old-growth forests. They are establishing interaction networks with several other functional groups of organisms such as hyperparasites, consumers, disease facilitators, indirect opportunistic species (such as tree hollow dwellers), saprotrophs or mutualists. Being connected to old trees (rare or missing components of managed forests) or to endangered forest plants, pathogens become indicators of naturalness and biodiversity. The gradient going from saprotrophs, to sapro-pathogens and generalist/specialist pathogens characterizing forest ecosystems is linked at great extent to wood and bark, being connected to nutrient cycling as ecosystem level process. As long as disease is maintained within the baseline mortality of the trees, pathogens play the important role of control factors and contribute directly and indirectly to forest biodiversity. The current disease ecology progresses, the biodiversity integrative studies, and the new holistic approaches shaping modern ecology bring in the focus rare, endemic pathogens. These play several roles: as important control factors for plant populations, as components of the plants’ phenotypic niche and of the global biodiversity, as potential providers of services (sources of medicines) and as components of the intricate ecological webs. However, the comparisons between oldgrowth and managed forests biodiversity should be focused on species evenness (high evenness in old-growth forests versus low evenness in managed forests) and not particularly on species richness. Still, there are pathogens responsible for major biotic disturbances in forests worldwide, the invasive, alien or emerging pathogens threatening both old-growth forests and managed forests. [ABSTRACT FROM AUTHOR]

Questions: Aspen (Populus tremula) is declining in the old‐growth forests of boreal Fennoscandia. This threatens the numerous taxa that are dependent on old aspens, including many epiphytic lichens. Potential methods to aid epiphytic lichens on aspen are centered around treatments which affect the density of Norway spruce (Picea abies). In this study, we investigated how epiphytic lichen communities on aspen are affected by the variation of spruce density in the immediate vicinity of the focal aspen. Location: Southern boreal forests in Finland. Methods: We recorded the occurrence of lichens from 120 aspens in 12 semi‐natural forest sites. We used spruce basal area as the measure for spruce density. The selected aspens represented a gradient in spruce basal area in the vicinity of the aspen from 0 to 36 m2/ha. We also measured other tree‐ and stand‐level variables that are known to influence lichen occurrence. Results: Lichen communities on aspen were affected by spruce density, stand age and bark pH. Both lichen species richness and the richness of red‐listed species were highest at an intermediate spruce density, and both increased with stand age. Lichen species richness was higher when bark pH was lower. Additionally, community composition was influenced the most by spruce density, followed by bark pH. Conclusions: Our study highlights the detrimental effects of high spruce density on lichen diversity on aspens. This is caused by high spruce density resulting in low light availability. Lichen diversity on aspens was highest when spruce density was intermediate. Spruce thinning in aspen‐rich old‐growth forests can be helpful in ensuring the long‐term persistence of old‐growth lichens on aspen in protected forests.We studied the effect of spruce density on lichen communities on aspen throughout the gradient of spruce density. The effect was significant, and lichen diversity on aspens was highest when spruce density was intermediate. Additionally, we found stand age and bark pH to have significant effects on lichen communities on aspen. [ABSTRACT FROM AUTHOR]

Over the last three decades, worldwide forests have become increasingly the focus of societal and scientific interest. The critical ecosystem services they provide are considered as key elements to mitigate harmful effects of global changes. Most of recent studies highlighted the highest effectiveness of the so-called «primary», «natural» and «old-growth forests» in this struggle due to their specific features (biodiversity and carbon storage capacity). However, in Europe, these forests which represent less than 1% of total forest cover are threatened by unsustainable human activity. Mainly based on pure ecological investigations, most of recent studies have rarely integrated human dimensions so far. Several outstanding issues remain to be addressed about the real nature of the «remaining natural European forests». Tackling this issue is crucial to know which forest must be conserved and how. In order to improve (i) knowledge about and (ii) conservation and/or sustainable management of such forests, we carried out an integrative and innovative research combining natural, social and human science approaches on a recently classified UNESCO primary beech forest located in the Maramureş county (Eastern Carpathians, Romania). First results highlighted that far from being untouched, this current high-value forest results from a long-term co-evolution with local communities. It implies a deeper understanding of the complex interaction between ecological and anthropogenic legacies is mandatory to improve and grant the preservation and sustainability of old-growth forests. [ABSTRACT FROM AUTHOR]

In Laos, there are extensive shifting cultivation areas and regrowth forests spontaneously established on fallow lands. The aims of the study were to conduct a comparative study of old-growth and regrowth forests in terms of structure, woody species diversity and composition as well as to investigate the potential role of regrowth forests in the conservation and restoration of degraded forest lands in Laos and the tropics in general. Systematic plot sampling was used to survey the floristic diversity, species composition and structure of old-growth and regrowth forests. Concentric circular plots with an area of 200 m2 and 500 m2 were laid on line transects. A total of 24 plots were sampled from two sites. In comparison to regrowth forests, old-growth forests had higher structural heterogeneity because of higher canopy height variations, vertical stratification, and tree sizes and their variations. Species richness and diversity indices values were similar, but abundance and species composition were significantly different between old-growth and regrowth forests. It appears that species richness recovers first followed by forest structure and species composition. Regrowth forests are important for in situ conservation of tropical biodiversity and they can also serve as a conduit for the restoration of degraded lands and forests. Regrowth forests provide habitats, serve as buffer zones around the fragmented old-growth forests, function as source of propagules, and enhance landscape connectivity. Utilization of regrowth forests for restoration purposes is comparatively inexpensive. Regrowth forests should be given the due considerations in the national forest conservation and restoration policy of Laos. [ABSTRACT FROM AUTHOR]

• Microclimate is more variable in managed compared to old-growth forests • Early successional stages are less thermally buffered in managed stands • It takes 50–60 years after clearcutting to recover forest microclimate conditions • Adopting a harvest inspired by natural forest dynamics is a suitable strategy for climate smart forestry Microclimate is a key driver of forest dynamics and shapes the response of forest organisms to global warming. The spatial and temporal variability of microclimate is strongly affected by forest management, so it is important to know how microclimate varies along successional gradients of managed forests, and how microclimatic dynamics in managed forests differ from those in old-growth forests. We measured forest understorey microclimate along successional gradients in regularly harvested forests and old-growth beech forests affected only by natural disturbances in the Western Carpathians (Central Europe) over a period of three years. We analysed how temperature and vapour pressure deficit (VPD) depended on forest structure and stand age, and how microclimate of managed stands differed from natural old-growth forests. Across forest landscapes we found that microclimatic conditions in managed forests were much more variable than in old-growth forests. Threshold analysis indicated that it takes approximately 54 years after clearing for microclimate to recover to conditions typical of old-growth and mature managed stands. Current forest management cycles create a microclimate landscape that is more dynamic in both space and time than the conditions to which many forest organisms are adapted in old-growth temperate forests in Europe. Adopting a harvesting approach inspired by temporal dynamics of old-growth forests, such as small-scale clearings with remnant trees providing microclimate refugia, is a suitable strategy for climate smart forestry to maintain microclimate buffering in managed forests. By increasing thermal habitat continuity, such options may help integrate biodiversity conservation targets into forest management programmes under climate change. [ABSTRACT FROM AUTHOR]

The Northwest Forest Plan (NWFP) initiated one of the most sweeping changes to forest management in the world, affecting 10 million hectares of federal land. The NWFP is a science-based plan incorporating monitoring and adaptive management and provides a unique opportunity to evaluate the influence of policy. We used >25 years of region-wide bird surveys, forest data, and landownership maps to test this policy's effect on biodiversity. Clearcutting decreased rapidly, and we expected populations of olderforest- associated birds to stabilize on federal land, but to continue declining on private industrial lands where clearcutting continued. In contrast, we expected declines in early-seral-associated species on federal land because of reduced anthropogenic disturbance since the NWFP. Bayesian hierarchical models revealed that bird species' population trends tracked changes in forest composition. However, against our expectations, declines of birds associated with older forests accelerated. These declines are partly explained by losses of older forests due to fire on federal land and continued clearcutting elsewhere. Indeed, the NWFP anticipated that reversing declines of older forests would take time. Overall, the early-seral ecosystem area was stable, but declined in two ecoregions--the Coast Range and Cascades--along with early-seral bird populations. Although the NWFP halted clearcutting on federal land, this has so far been insufficient to reverse declines in older-forest-associated bird populations. These findings underscore the importance of continuing to prioritize older forests under the NWFP and ensuring that the recently proposed creation of early-seral ecosystems does not impede the conservation and development of older-forest structure. [ABSTRACT FROM AUTHOR]

We present an updated checklist for Konevets Island (Leningrad Region, Russia). The revealed lichen biota comprises 435 species, including 378 lichens, 46 lichenicolous fungi and 11 non-lichenized saprobic fungi, of which 31 species (27 lichens and 4 lichenicolous fungi) are known only from collections made by Veli Räsänen (1917, 1938). Acremonium hypholomatis is reported for the first time for Russia; Caloplaca soralifera, Trapelia corticola, and Muellerella lichenicola for Northwestern European Russia; and Bacidia vermifera, Lecanora mughicola, Micarea contexta, Pyrenochaeta xanthoriae, Rhizocarpon disporum, Stigmidium squamariae and Xylographa difformis for Leningrad Region. From lichenological point of view, the most valuable habitats of Konevets Island are old-growth spruce forests. The studied lichen biota is rich and diverse and exceptionally wellpreserved in comparison to the mainland part of Karelian Isthmus. It definitely deserves protection. [ABSTRACT FROM AUTHOR]

Osmoderma eremita (Scopoli, 1763) is a saproxylic scarab beetle protected by the Habitats Directive in the European Union. The present paper is part of a special issue on monitoring of saproxylic beetles protected in Europe and starts with a revision of the current knowledge on systematics, ecology, ethology and conservation of O. eremita and its allied species, followed by experimental tests of different methods for monitoring its populations. Two methods were compared in several localities of central Italy: (1) the widely used pitfall traps into tree cavities and (2) black cross windows traps baited with a specific pheromone produced by male beetles. The first method, often used in northern and central Europe, did not give acceptable results in Italy probably because of the scarcity of veteran trees with large hollows. It could only be used successfully in areas where: 1) tree hollows were abundant, large enough and with sufficient amounts of wood mould for planting pitfall traps and 2) the team is composed of several operators in order to ensure the checking of at least 150 traps every two days during the whole period of mating activities (15 July-25 August). The second method, consisting of hanging 30 black cross window traps during the mating period and checking them every two days, turned out to be better for capturing a significant number of individuals but cannot be used every year because of the possible disturbance on mating activities of the species. [ABSTRACT FROM AUTHOR]

The maintenance of certain levels of old forest represents a cornerstone of the EU's biodiversity management strategy. A consensus on a single general ecological definition of old-growth is particularly difficult in Mediterranean Europe. The present paper deals with old-growth forests and persistent woodlands in the Cilento and Vallo di Diano National Park (PNCVD) to give an ecological understanding of forest complexity and dynamics under a multiscale and multidisciplinary perspective. The multiscale approach ranged from the identification and mapping of potential old-growth stands at landscape scale to a two-level field review of forest stand features. Field sampling involved a multidisciplinary team of researchers in forest structure, pedologic environment, soil microbial activity, flora and vegetation and deadwood components. The research provided sound knowledge about old-growthness features in the PNCVD that constitutes a unique case study in the whole Mediterranean basin. The integration of results allowed to: identify main ecosystem functions and the related services of the old-growth forests in the study area; distinguish persistent woodlands, multi-aged stands with old trees deriving from nineteenth-century management practices, from old-growth forests sensu strictu; recognize indicators of direct and indirect impacts of human activities; suggest effective practices for sustainable management in the Mediterranean context. [ABSTRACT FROM AUTHOR]

Coastal rainforests of southeast Alaska have relatively simple species composition but complex structures with high diversity of tree ages, sizes and forest canopy layers, and an abundant understory plant community. Wildlife and fisheries resources also play an important role in the ecological functioning of forest and aquatic systems. Clearcutting has greatly altered these forest ecosystems with significant decreases in structural diversity of forest stands and greatly reduced wildlife habitat. This paper synthesizes information on management options in older forests that have never been actively managed, and in younger forests to increase diversity of stand structures and their associated effects on biodiversity. Light to moderate levels of partial cutting in old-growth forests can maintain the original diversity of overstory stand structures and understory plant communities. In younger forests that develop after clearcutting, mixed alder-conifer stands provide more heterogeneous structures and significantly higher understory biomass than in pure conifer forests. Research has shown that red alder increases diversity and abundance of understory plants, and provides forage for deer and small mammals. Results also show a clear linkage between alder and improved invertebrate diversity in aquatic systems. A combination of light partial cutting in older forests along with inclusion of red alder in conifer-dominated forests could provide the greatest amount of diversity and maintain the complex stand structures that are an important component of these forest ecosystems. [Copyright &y& Elsevier]

Copyright of VertigO is the property of La Revue Electronique en Sciences de l'Environnement VertigO 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.)

Copyright of Forestry Chronicle is the property of Canadian Institute of Forestry 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 ecological implications of the conversion of old-growth temperate rainforests to managed forests have generated much discussion worldwide. This paper examines the effects of such a conversion on different aspects of the biodiversity of the soil collembolan fauna, and attempts to determine the time that will be required for the collembolan fauna to approach the abundance and community structure seen in old-growth forests. The study also investigates the potential of using different measures of species diversity and community structure as indicators of old-growth conditions in forest soils. The study was carried out in three chronosequence sites in Douglas-fir dominated stands on the dry leeward eastern side of Vancouver Island, BC, Canada. Each of the three sites contained stands representing four stages of stand development: regeneration (7–9 years), immature (35–46 years), mature (80–102 years) and old-growth (>248 years). The Collembola were extracted from litterbags containing needle litter or wood chips, and from the forest floor (LFH) layer in the late autumn of four successive years.Overall abundance of Collembola was highest in the old-growth and lowest in the regeneration stands. Although population numbers in the immature and mature forests were significantly higher than in regeneration stands, they still had not achieved the levels observed in old-growth forests. In the forest floor, species richness was low in regeneration stands compared to later stages of stand development, but did not differ significantly among immature, mature and old-growth stands. Measures of species diversity based on Shannon’s and Simpson’s indices of diversity did not differ significantly according to the stage of stand development.It was not possible to distinguish individual collembolan species that could be used as indicators of old-growth conditions. The same species occurred in most or all stand ages, with differences being determined by changes in relative and absolute abundance of the species comprising the community. However, principal component analysis of data on the Collembola of needle litterbags and the LFH layer showed that the collembolan community of the regeneration stands could be clearly differentiated from those of the forested stands. In addition, the collembolan communities of 80–102-year-old forests could still be distinguished from those of the old-growth forests. In contrast, the collembolan fauna of decomposing wood chips was very similar in all stand ages, with the exception of the regeneration stands. [Copyright &y& Elsevier]