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1.
Aim  The analysis of the phylogeographical structures of many European species reveals the importance of Mediterranean glacial refugia for many thermophilic species, but also underlines the relevance of extra-Mediterranean glacial differentiation centres for a number of temperate species. In this context, phylogeographical analyses of species from south-eastern Europe are highly important for a comprehensive understanding of Europe as a whole.
Location  Romania and Bulgaria.
Methods  We analysed 19 allozyme loci for 615 individuals of the temperate butterfly species Erebia medusa from 28 populations.
Results  These populations had an intermediate genetic diversity, but the Bulgarian populations were significantly more diverse than the ones north of the Danube in Romania. The differentiation among populations was strong, and 52.1% of the genetic variance among populations was distributed between these two countries. The genetic differentiation was considerably stronger in Romania than in Bulgaria, but several sublineages were distinguished within each of these countries.
Main conclusions  The observed genetic structure is so strong that it is most probably the result of glacial differentiation processes in south-eastern Europe and not a post-glacial structure. The strong differentiation into the two groups north and south of the Danube suggests a separating effect by this river valley. The strong differentiation accompanied with genetic impoverishment in Romania suggests the existence of several differentiation centres: at least two small ones on the southern slopes of the southern Carpathians and one in the eastern Carpathian Basin. The considerably weaker differentiation among the Bulgarian samples and their significantly higher genetic diversity imply that gene flow occurred among different regions of Bulgaria during the last ice age.  相似文献   

2.
Forestry management worldwide has become increasingly effective at obtaining high timber yields from productive forests. In New Zealand, a focus on improving an increasingly successful and largely Pinus radiata plantation forestry model over the last 150 years has resulted in some of the most productive timber forests in the temperate zone. In contrast to this success, the full range of forested landscapes across New Zealand, including native forests, are impacted by an array of pressures from introduced pests, diseases, and a changing climate, presenting a collective risk of losses in biological, social and economic value. As the national government policies incentivise reforestation and afforestation, the social acceptability of some forms of newly planted forests is also being challenged. Here, we review relevant literature in the area of integrated forest landscape management to optimise forests as nature-based solutions, presenting ‘transitional forestry’ as a model design and management paradigm appropriate to a range of forest types, where forest purpose is placed at the heart of decision making. We use New Zealand as a case study region, describing how this purpose-led transitional forestry model can benefit a cross section of forest types, from industrialised forest plantations to dedicated conservation forests and a range of multiple-purpose forests in between. Transitional forestry is an ongoing multi-decade process of change from current ‘business-as-usual’ forest management to future systems of forest management, embedded across a continuum of forest types. This holistic framework incorporates elements to enhance efficiencies of timber production, improve overall forest landscape resilience, and reduce some potential negative environmental impacts of commercial plantation forestry, while allowing the ecosystem functioning of commercial and non-commercial forests to be maximised, with increased public and biodiversity conservation value. Implementation of transitional forestry addresses tensions that arise between meeting climate mitigation targets and improving biodiversity criteria through afforestation, alongside increasing demand for forest biomass feedstocks to meet the demands of near-term bioenergy and bioeconomy goals. As ambitious government international targets are set for reforestation and afforestation using both native and exotic species, there is an increasing opportunity to make such transitions via integrated thinking that optimises forest values across a continuum of forest types, while embracing the diversity of ways in which such targets can be reached.  相似文献   

3.
Retention forestry, which retains a portion of the original stand at the time of harvesting to maintain continuity of structural and compositional diversity, has been originally developed to mitigate the impacts of clear‐cutting. Retention of habitat trees and deadwood has since become common practice also in continuous‐cover forests of Central Europe. While the use of retention in these forests is plausible, the evidence base for its application is lacking, trade‐offs have not been quantified, it is not clear what support it receives from forest owners and other stakeholders and how it is best integrated into forest management practices. The Research Training Group ConFoBi (Conservation of Forest Biodiversity in Multiple‐use Landscapes of Central Europe) focusses on the effectiveness of retention forestry, combining ecological studies on forest biodiversity with social and economic studies of biodiversity conservation across multiple spatial scales. The aim of ConFoBi is to assess whether and how structural retention measures are appropriate for the conservation of forest biodiversity in uneven‐aged and selectively harvested continuous‐cover forests of temperate Europe. The study design is based on a pool of 135 plots (1 ha) distributed along gradients of forest connectivity and structure. The main objectives are (a) to investigate the effects of structural elements and landscape context on multiple taxa, including different trophic and functional groups, to evaluate the effectiveness of retention practices for biodiversity conservation; (b) to analyze how forest biodiversity conservation is perceived and practiced, and what costs and benefits it creates; and (c) to identify how biodiversity conservation can be effectively integrated in multi‐functional forest management. ConFoBi will quantify retention levels required across the landscape, as well as the socio‐economic prerequisites for their implementation by forest owners and managers. ConFoBi's research results will provide an evidence base for integrating biodiversity conservation into forest management in temperate forests.  相似文献   

4.

Aim

Primary forests have high conservation value but are rare in Europe due to historic land use. Yet many primary forest patches remain unmapped, and it is unclear to what extent they are effectively protected. Our aim was to (1) compile the most comprehensive European‐scale map of currently known primary forests, (2) analyse the spatial determinants characterizing their location and (3) locate areas where so far unmapped primary forests likely occur.

Location

Europe.

Methods

We aggregated data from a literature review, online questionnaires and 32 datasets of primary forests. We used boosted regression trees to explore which biophysical, socio‐economic and forest‐related variables explain the current distribution of primary forests. Finally, we predicted and mapped the relative likelihood of primary forest occurrence at a 1‐km resolution across Europe.

Results

Data on primary forests were frequently incomplete or inconsistent among countries. Known primary forests covered 1.4 Mha in 32 countries (0.7% of Europe’s forest area). Most of these forests were protected (89%), but only 46% of them strictly. Primary forests mostly occurred in mountain and boreal areas and were unevenly distributed across countries, biogeographical regions and forest types. Unmapped primary forests likely occur in the least accessible and populated areas, where forests cover a greater share of land, but wood demand historically has been low.

Main conclusions

Despite their outstanding conservation value, primary forests are rare and their current distribution is the result of centuries of land use and forest management. The conservation outlook for primary forests is uncertain as many are not strictly protected and most are small and fragmented, making them prone to extinction debt and human disturbance. Predicting where unmapped primary forests likely occur could guide conservation efforts, especially in Eastern Europe where large areas of primary forest still exist but are being lost at an alarming pace.  相似文献   

5.
In this study, we investigated the diversity and ecology of Armillaria species in virgin pure beech and mixed conifer forests (15,000 ha) of the Carpathian Biosphere Reserve in Ukraine. Armillaria rhizomorphs were systematically sampled, both from the soil and from the root collar of trees (epiphytic), on 79 plots (25 × 20 m) of a 1.5 × 1.5 km grid. In both forest massifs, rhizomorphs were present in the majority of the soil samples, with an estimated dry weight of 512 kg/ha in the pure beech forests and 223 kg/ha in the mixed conifer forests. Similarly, in both forest massifs, most of the trees inspected had rhizomorphs at the root collar. Species identification based on DNA analyses showed that all five annulated European Armillaria species occur in these virgin forests, as previously observed in managed forests in central Europe. However, differences in the frequencies of the single species were observed. The predominance of the preferentially saprotrophic A. cepistipes and A. gallica (84 and 15% of the specimens, respectively) and the absence of significant pathogenic activity suggest that in these virgin forests Armillaria species are most likely to behave as saprotrophs. Forest management may increase the frequency of the pathogenic species A. ostoyae, which is rare in virgin forests.  相似文献   

6.
Aim Although Abies alba is not yet prioritized for conservation in many European countries, its importance is acknowledged under the EU Directive on the marketing for forest reproductive material. The Apuseni National Park contains one of the largest areas of remnant native A. alba in central eastern Europe. Here, we examine the antiquity of the present A. alba communities in the forests of NW Romania and the drivers behind their variability over the last 6000 years leading to current distribution pattern. Location The Apuseni National Park (ANP), NW Romania. Methods We use fossil pollen, microscopic and macroscopic charcoal and AMS14C dating on four sedimentary sites in the west‐central ANP. Results The results reveal that stands of A. alba have been growing in NW Romania from at least 5700 yr bp and occurred in low abundance until 4200 yr bp . A. alba expanded thereafter and it thrived in multispecies forest stands with Fagus, Picea, Carpinus, Tilia, Quercus and Ulmus between 4200 and 1200 yr bp . The initial expansion occurred during an independently documented period of high moisture and cooler temperature as inferred from isotope data from cave stalagmites within this region. The final decline in A. alba abundance and distribution started from about 1200 yr bp and reached an unprecedently low value over the last 300 years, which was primarily caused by the increase in human activities in the region through deforestation, forest browsing and burning, and commercial forestry. Main conclusion Different management strategies ranging from restriction on harvesting and browsing need to be implemented in this region if A. alba is going to survive the forecasted decrease in precipitation and increase in temperature, which will further reduce its spatial distribution.  相似文献   

7.
China’s forests are characterized by young forest age, low carbon density and a large area of planted forests, and thus have high potential to act as carbon sinks in the future. Using China’s national forest inventory data during 1994–1998 and 1999–2003, and direct field measurements, we investigated the relationships between forest biomass density and forest age for 36 major forest types. Statistical approaches and the predicted future forest area from the national forestry development plan were applied to estimate the potential of forest biomass carbon storage in China during 2000–2050. Under an assumption of continuous natural forest growth, China’s existing forest biomass carbon (C) stock would increase from 5.86 Pg C (1 Pg=1015 g) in 1999–2003 to 10.23 Pg C in 2050, resulting in a total increase of 4.37 Pg C. Newly planted forests through afforestation and reforestation will sequestrate an additional 2.86 Pg C in biomass. Overall, China’s forests will potentially act as a carbon sink for 7.23 Pg C during the period 2000–2050, with an average carbon sink of 0.14 Pg C yr−1. This suggests that China’s forests will be a significant carbon sink in the next 50 years.  相似文献   

8.
In spite of the high importance of forests, global forest loss has remained alarmingly high during the last decades. Forest loss at a global scale has been unveiled with increasingly finer spatial resolution, but the forest extent and loss in protected areas (PAs) and in large intact forest landscapes (IFLs) have not so far been systematically assessed. Moreover, the impact of protection on preserving the IFLs is not well understood. In this study we conducted a consistent assessment of the global forest loss in PAs and IFLs over the period 2000–2012. We used recently published global remote sensing based spatial forest cover change data, being a uniform and consistent dataset over space and time, together with global datasets on PAs’ and IFLs’ locations. Our analyses revealed that on a global scale 3% of the protected forest, 2.5% of the intact forest, and 1.5% of the protected intact forest were lost during the study period. These forest loss rates are relatively high compared to global total forest loss of 5% for the same time period. The variation in forest losses and in protection effect was large among geographical regions and countries. In some regions the loss in protected forests exceeded 5% (e.g. in Australia and Oceania, and North America) and the relative forest loss was higher inside protected areas than outside those areas (e.g. in Mongolia and parts of Africa, Central Asia, and Europe). At the same time, protection was found to prevent forest loss in several countries (e.g. in South America and Southeast Asia). Globally, high area-weighted forest loss rates of protected and intact forests were associated with high gross domestic product and in the case of protected forests also with high proportions of agricultural land. Our findings reinforce the need for improved understanding of the reasons for the high forest losses in PAs and IFLs and strategies to prevent further losses.  相似文献   

9.
With the expanding unification of Europe, the face of European science is changing. For some countries these changes are more pronounced than for others. Here, we survey the present state of science, most notably molecular biology research, in Eastern and South-Eastern European countries. We focus on the strategies these countries are taking in their quest for scientific excellence, discuss some of the acute challenges they face and explore several success stories in the making.  相似文献   

10.
Plantation forests and biodiversity: oxymoron or opportunity?   总被引:3,自引:1,他引:2  
Losses of natural and semi-natural forests, mostly to agriculture, are a significant concern for biodiversity. Against this trend, the area of intensively managed plantation forests increases, and there is much debate about the implications for biodiversity. We provide a comprehensive review of the function of plantation forests as habitat compared with other land cover, examine the effects on biodiversity at the landscape scale, and synthesise context-specific effects of plantation forestry on biodiversity. Natural forests are usually more suitable as habitat for a wider range of native forest species than plantation forests but there is abundant evidence that plantation forests can provide valuable habitat, even for some threatened and endangered species, and may contribute to the conservation of biodiversity by various mechanisms. In landscapes where forest is the natural land cover, plantation forests may represent a low-contrast matrix, and afforestation of agricultural land can assist conservation by providing complementary forest habitat, buffering edge effects, and increasing connectivity. In contrast, conversion of natural forests and afforestation of natural non-forest land is detrimental. However, regional deforestation pressure for agricultural development may render plantation forestry a ‘lesser evil’ if forest managers protect indigenous vegetation remnants. We provide numerous context-specific examples and case studies to assist impact assessments of plantation forestry, and we offer a range of management recommendations. This paper also serves as an introduction and background paper to this special issue on the effects of plantation forests on biodiversity.
Eckehard G. BrockerhoffEmail:
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11.
During the last century the black woodpecker Drycopus maritus has expanded m range in central and western Europe Habitat changes were the most common explanations of these expansions I compared changes m forest characteristics in countries where different black woodpecker population trends were observed Results showed that countries with positive population trends had significantly higher increase in coniferous forest volume These countries had also significantly higher proportion of young forest stands The importance of coniferous forests, as well as importance of forest structure for the black woodpecker, are discussed  相似文献   

12.
The importance of harmonizing the group of terms used to indicate ‘natural’ forests is reported in several studies. In a recent paper the term virgin forest is proposed as a unifying concept for forests which are not influenced by man in their development. In response to that paper my aim is to clarify the terms virgin and old-growth. My response focuses on two points: the term virgin forest is generally used to indicate forests that have not been influenced by people even in the distant past, therefore something different from what described by the authors; the definition drawn up for the proposed term substantially overlaps with the definition of old-growth forest resulting from a long history of studies on this theme. I think that the overlap between the two analyzed terms can ultimately only increase the existing confusion on this group of forest terms.  相似文献   

13.
刘琦  蔡慧颖  金光泽 《生态学杂志》2013,24(10):2709-2716
准确量化森林碳密度和净初级生产力(NPP)对于评价森林生态系统在全球碳循环中的作用至关重要.本研究以小兴安岭原始阔叶红松林和择伐(择伐强度30%,择伐对象为大径级红松)34年后的阔叶红松林为对象,采用样地清查和异速生长方程法测定了不同林分的碳密度和NPP.结果表明: 原始林和择伐林的碳密度总量分别为(397.95±93.82)和(355.61±59.37) t C·hm-2,其中植被碳密度、碎屑碳密度、土壤碳密度分别占总碳库的31.0%、3.1%、65.9%和31.7%、2.9%、65.4%,两者的总碳密度和各组分的分配比例均无显著差异. 原始林和择伐林的NPP总量分别为(6.27±0.36 )和(6.35±0.70) t C·hm-2·a-1,乔木层、灌木和草本层、细根所占比例分别为60.3%、2.0%、37.7%和66.1%、2.0%、31.2%,两者的总NPP和各组分的贡献率均无显著差异.而原始林和择伐林中针、阔叶的NPP比例分别为4724∶52.76和20.48∶79.52,两者差异显著.择伐34年后阔叶红松林的碳密度和NPP均达到了择伐前水平.  相似文献   

14.
Little is known about the importance of the forest overstorey relative to other factors in controlling the spatial variability in understorey species composition in near-natural temperate broadleaved forests. We addressed this question for the 19 ha ancient forest Suserup Skov (55°22′ N, 11°34′ E) in Denmark, one of the few old-growth temperate broadleaved forest remnants in north-western Europe, by inventorying understorey species composition and environmental conditions in 163 100 m2 plots. We use unconstrained and constrained ordinations, variation partitioning, and Indicator Species Analysis to provide a quantitative assessment of the importance of the forest overstorey in controlling understorey species composition. Comparison of the gradients extracted by unconstrained and constrained ordinations showed that the main gradients in understorey species composition in our old-growth temperate broadleaved forest remnant are not caused by variability in the forest overstorey, but are related to topography and soil, edge effects, and unknown broad-scale factors. Nevertheless, overstorey-related variables uniquely accounted for 15% of the total explained variation in understorey species composition, with the pure overstorey-related (Rpo), topography and soil (Rpt), edge and anthropogenic disturbance effects (Rpa), and spatial (Rps) variation fractions being of equal magnitude. The forward variable selection showed that among the overstorey-related variables understorey light availability and to a lesser extent vertical forest structure were most important for understorey species composition. No unique influence of overstorey tree species identity could be documented. There were many indicator species for high understorey light levels and canopy gap centres, but none for medium or low light or closed canopy. Hence, no understorey species behaved as obligate shade plants. Our study shows that, the forest overstorey has a weak control of understorey species composition in near-natural broadleaved forest, in contrast to results from natural and managed forests comprising both conifer and broadleaved species. Nevertheless, >20% of the understorey species found were indicators of high light conditions or canopy openings. Hence, variability in canopy structure and understorey light availability is important for maintaining understorey species diversity.  相似文献   

15.
基于森林资源清查资料分析山东省森林立木碳储量   总被引:2,自引:0,他引:2  
利用山东省第7次森林资源清查数据,采用生物量-蓄积量转换函数和平均生物量法,结合不同树种的含碳率,研究山东省森林生态系统立木碳储量、碳密度及其按优势树种、龄组和林种的分布特征.结果表明: 2007年山东省森林立木碳储量为25.27 Tg,其中,针叶林、针阔混交林和阔叶林的立木碳储量分别占全省立木碳储量的8.6%、2.0%和89.4%.不同林龄组的立木碳储量大小顺序为幼龄林>中龄林>成熟林>近熟林>过熟林,其中幼龄林和中龄林占全省立木总碳储量的69.3%.用材林、经济林和防护林的立木碳储量分别占全省立木碳储量的37.1%、36.3%和24.8%.山东省森林平均立木碳密度为10.59 t·hm-2,低于全国平均水平,主要是由于现有森林用材林和经济林比重高,中幼林多、成过熟林少.
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16.
Pine wilt disease, which can rapidly kill pines, is caused by the pine wood nematode, Bursaphelenchus xylophilus. It is expanding its range in many countries in Asia and measures are being taken at the EU level to prevent its spread from Portugal. Due to the threat to European forests, it is important to prevent additional introductions and target surveillance to the points of entry that pose the greatest risk. In this study, we present a model to identify the European ports from which the nematode can spread most rapidly across Europe. This model describes: (1) the potential spread of the pine wood nematode based on short-distance spread (the active flight of the vector beetles) and long-distance spread (primarily due to human-mediated transportation), and (2) the development of pine wilt disease based on climate suitability and the potential spread of the nematode. Separate introductions at 200 European ports were simulated under various climate change scenarios. We found that the pine wood nematode could invade 19–60% of the study area (30°00 N–72°00 N, 25°00 W–40°00 E) by 2030, with the highest spread from ports located in Eastern and Northern Europe. Based on climate change scenarios, the disease could affect 8–34% of the study area by 2030, with the highest spread from ports located in South-Eastern Europe. This study illustrates how a spread model can be used to determine the critical points of entry for invasive species, so that surveillance can be targeted more accurately and control measures prioritised.  相似文献   

17.
Records of the predaceous diving beetles of the genus Eretes Laporte, 1833 (Coleoptera: Dytiscidae) in Central Europe are summarised. While old records from the beginning of the twentieth century from the Czech Republic, Hungary, and Romania belong to Eretes griseus (Fabricius, 1781), a species which has not been recaptured in Central Europe for nearly the last hundred years, recently collected specimens from Hungary and Slovakia belong to E. sticticus (Linnaeus, 1767) and represent its first records in these countries as well as in Central Europe. The first specimens were collected at light during hot summer nights and may document a recent spreading of the species from the Mediterranean. In addition, the occurrence of E. sticticus is formally confirmed in Bulgaria, Croatia, Greece, Israel, Libya, South European Territory of Russia, and Tunisia.  相似文献   

18.
Natural disturbance regimes are changing substantially in forests around the globe. However, large‐scale disturbance change is modulated by a considerable spatiotemporal variation within biomes. This variation remains incompletely understood particularly in the temperate forests of Europe, for which consistent large‐scale disturbance information is lacking. Here, our aim was to quantify the spatiotemporal patterns of forest disturbances across temperate forest landscapes in Europe using remote sensing data and determine their underlying drivers. Specifically, we tested two hypotheses: (1) Topography determines the spatial patterns of disturbance, and (2) climatic extremes synchronize natural disturbances across the biome. We used novel Landsat‐based maps of forest disturbances 1986–2016 in combination with landscape analysis to compare spatial disturbance patterns across five unmanaged forest landscapes with varying topographic complexity. Furthermore, we analyzed annual estimates of disturbances for synchronies and tested the influence of climatic extremes on temporal disturbance patterns. Spatial variation in disturbance patterns was substantial across temperate forest landscapes. With increasing topographic complexity, natural disturbance patches were smaller, more complex in shape, more dispersed, and affected a smaller portion of the landscape. Temporal disturbance patterns, however, were strongly synchronized across all landscapes, with three distinct waves of high disturbance activity between 1986 and 2016. All three waves followed years of pronounced drought and high peak wind speeds. Natural disturbances in temperate forest landscapes of Europe are thus spatially diverse but temporally synchronized. We conclude that the ecological effect of natural disturbances (i.e., whether they are homogenizing a landscape or increasing its heterogeneity) is strongly determined by the topographic template. Furthermore, as the strong biome‐wide synchronization of disturbances was closely linked to climatic extremes, large‐scale disturbance episodes are likely in Europe's temperate forests under climate changes.  相似文献   

19.
Understanding and unravelling the direct and indirect effects of ongoing and predicted climate change on the vitality and productivity of Scots pine forests is particularly important for Romania and other parts of eastern Europe, where the species represents an essential ecological and economic value. Here, we introduce the first nation-wide network of 34 Scots pine chronologies of basal area increment (BAI), and assess the species’ vulnerability to climate change. Temperatures of the previous autumn, as well as current year spring and summer warmth are found to be most critical for the productivity of Romania’s Scots pine forests. Negative growth anomalies after hot and dry August conditions are most severe in young (<50 years) Scots pine monocultures (>70% dominance) at lower elevations (<1000 m a.s.l.) across western Romania. Our findings emphasise the relevance and timeliness of carefully adapting sylvicultural management strategies to enhance the ecological and economic resilience of Romania’s widespread forest areas under a warmer and drier future climate.  相似文献   

20.
Abstract. Question: Which are the structural attributes and the history of old‐growth Fagus forest in Mediterranean montane environments? What are the processes underlying their structural organization? Are these forests stable in time and how does spatial scale affect our assessment of stability? How do these forests compare to other temperate deciduous old‐growth forests? Location: 1600–1850 m a.s.l., Fagus forest near the tree line, central Apennines, Italy. Methods: An old‐growth Fagus forest was studied following historical, structural and dendroecological approaches. History of forest cover changes was analysed using aerial photographs taken in 1945, 1954, 1985 and 1994. The structural analysis was carried out in the primary old‐growth portion of the forest using 18 circular and two rectangular plots. Dendroecological analyses were conducted on 32 dominant or co‐dominant trees. Results: These primary old‐growth Fagus remnants consist of four patches that escaped logging after World War II. Both living and dead tree components are within the range of structural attributes recognized for old‐growth in temperate biomes. Dendroecological analyses revealed the roles of disturbance, competition and climate in structuring the forest. We also identified a persistent Fagus community in which gap‐phase regeneration has led to a mono‐specific multi‐aged stand at spatial scales of a few hectares, characterized by a rotated‐sigmoid diameter distribution. Conclusion: Even at the relatively small spatial scale of this study, high‐elevation Apennine Fagus forests can maintain structural characteristics consistent with those of old‐growth temperate forests. These results are important for managing old‐growth forests in the Mediterranean montane biome.  相似文献   

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