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1.
Large herbivores are keystone species in many forest areas, as they shape the structure, species diversity and functioning of those ecosystems. The European bison Bison bonasus has been successfully restored after extinction in the wild at the beginning of 20th century. As free-ranging populations of the species were re-established mainly in forest habitats, knowledge of the impact by the largest European terrestrial mammal on tree stands is essential. This helps to make management and conservation decisions for viable population maintenance of the species in the wild. Using a novel DNA-based method of herbivore diet analysis, the trnL approach (DNA-barcoding), we investigated the influence of different foraging conditions (access to supplementary fodder) on bison diet in winter and its potential impact on woody species. Faecal samples were collected from different bison treatment groups: (1) intensively fed; (2) less intensively fed; (3) non-fed utilising forest habitats; and (4) non-fed utilising agricultural areas surrounding the Forest. These were analysed to estimate the proportion of different plant groups consumed by bison. Bison groups differed significantly in their diet. The amount of woody materials (trees and shrubs) consumed by bison increased with decreasing access to supplementary fodder, ranging from 16% in intensively fed bison to 65% in non-fed bison utilising forest habitats. Inversely, the amount of herbs, grasses and sedges decreased from 82% in intensively fed bison to 32% in non fed bison utilising forest habitats. The species of trees mainly browsed by bison, Carpinus/ Corylus, Betula sp. and Salix sp., were of lower economic importance for forest management. The impact of bison on tree species needs further investigation, however, we can predict that browsing by bison, mainly on Carpinus/ Corylus, makes an insignificant impact on forestry due to the high and increasing representation of this species in the forest understory. Supplementary feeding has several negative effects on bison ecology and health, therefore reduced and distributed supplementary feeding should be applied as the management practice in the Bia?owie?a Forest. 相似文献
2.
Białowieża Primeval Forest lies within the boreal part of the Norway spruce range, which, according to pollen data, was formed
by a refugium located in the Russian Upland. However, recent genetic studies have indicated that spruce from the Eastern Carpathian
refugium also occurs in Białowieża Forest. In order to investigate whether the Norway spruce from the Eastern Carpathian refugium
migrated naturally into the boreal part of the Norway spruce range, we assessed the refugial origin of 234 of the oldest Norway
spruce individuals from Białowieża Forest using mitochondrial marker mt15- D02. Out of the trees that we studied, 64.8% carried mitotype 1, which is specific to the Carpathian refugium, while 35.2% had
mitotype 3, specific to the Russian refugium. Our genetic analysis, combined with historical data on forest management in
this part of Europe, argues for a natural contribution of spruce from the Eastern Carpathian refugium during postglacial recolonization
of Białowieża Primeval Forest. 相似文献
3.
We examined the year-round viable seed dispersal by European bison ( Bison bonasus L.) subject to three population management systems (captive, semi-wild, wild) in Bia?owie?a Primeval Forest. The forest is inhabited by the world's largest free-roaming population of European bison (>450 head). Dung samples were collected approximately fortnightly from September 2005 to September 2006 in each of the management systems. Emergent seedlings were counted for 24 months in greenhouse conditions. A total of 10,807 seedlings, which included 178 plant taxa, emerged from 74 bison dung samples. Species richness and seedling abundance/sample were greatest during August and September, the months of the highest fructification season, and were lowest in May. Twenty-two percent of recorded species were forest plants. The captive bison population had the greatest mean seedling abundance (236 ± 61/sample), the greatest species diversity (144), and the highest percentage of synanthropic species (29.2%). The gradient of these characteristics decreased with a decrease in management intensity of the bison populations. The results of the regression analysis indicated that in the semi-wild managed system, the number of plant species found in dung samples collected during winter was significantly negatively correlated with snow depth. Number of seedlings and number of plant species dispersed depended on plant phenology and intensity of supplementary feeding. The mean number of seeds/sample dispersed by European bison was 5–15 times lower, and the mean number of species/sample was 2–3 times lower than those published for cattle or horses. In contrast, the total number of plant species dispersed by bison was approximately 2–3 times higher than for wild or domestic large ungulates. These results indicate that European bison are an important dispersal agent of seeds in forest ecosystems. The high percentage of synanthropic species dispersed by bison demonstrated that seeds in the fodder help maintain native and non-native plant diversity of ecosystems. Managers of animal populations must pay proper attention to fodder origin and quality. 相似文献
4.
We studied temporal changes in the genetic structure and diversity of a naturally regenerated Picea abies (L.) Karst. (Norway spruce) population in the Bia?owie?a Primeval Forest, Poland. The analysis included five age classes of trees: newly germinating seedlings (in laboratory conditions), seedlings up to 3 years old, young trees 4–10 years old, middle-aged trees 11–100 years old, and trees older than 100 years. We conducted genetic analyses of 26 allozyme loci using dormant buds from 405 individuals and 100 embryos. The results showed that the naturally regenerating Norway spruce population is genetically heterogeneous across the studied age classes. As determined by Chi squared tests, there were statistically significant differences in frequencies of alleles and genotypes as well as Wright’s index values (F) among the five age classes. The level of genetic differentiation (pairwise F ST = 0.5–2.3 %) among the age class groups was equal to levels previously determined for various populations of this species. The Ewens-Watterson test for neutrality showed that one or two loci across different age classes of Norway spruce were affected by the selection process. The distinctiveness of embryo and seedling classes was confirmed by the number of detected alleles, the number of private alleles, the level of observed heterozygosity, and Wright’s index value. The results obtained in the present study indicate there are interesting dynamics of adaptation processes occurring in the natural age-diverse population of Norway spruce in the Bia?owie?a Primeval Forest. 相似文献
5.
? Key message Long-term strict protection of woodland communities may lead to their compositional simplification and homogenisation. ? Context In the past, it has often been postulated that structures and processes typical for natural forests should be mimicked by silvicultural activities in the case of managed tree stands. ? Aims To determine which features and traits of natural woodland communities (alongside typical old-growth attributes) should be imitated in managed forests, as well as which should not (and for what reasons). ? Methods Tree data from five permanent study plots (of a total area of 15.44 ha) established in 1936 in the core area of the Bia?owie?a National Park (NE Poland) are used to calculate several quantitative indices describing the temporal dynamics (in terms of stand structure and composition) of eight major woodland community types. ? Results Most structural attributes revealed rather high stability over time. In contrast to these, during the observation period, noticeable changes in the composition of particular Bia?owie?a woodland communities have been taking place, related to declining occurrence and reduced roles characteristic for a large number of tree species. ? Conclusion In many ways, natural forests can serve as an important model for managed forest stands. However, in certain circumstances, silvicultural treatments counteracting natural developmental trends may appear to be indispensable, especially when more diverse and stable tree species composition (at a given spatial and temporal scale) is indicated or desirable. 相似文献
6.
The purpose of this study is to investigate the impact of non-economic motivations such as altruism and environmental concerns on social preferences and hence willingness to pay (WTP) for changes in forest management strategies in the Białowieża Forest in Poland. We used data from a discrete choice experiment (CE) with attributes describing changes in the quality of the forest and recreation. The choice experiment technique makes it possible to disentangle the effect of the trait of altruism and environmental concern with regard to different attributes and their levels. Environmental attitudes were measured using the New Ecological Paradigm (NEP) scale, whereas the trait of altruism was determined using the Self-Reported Altruism (SRA) scale. The parameterization employed in the survey was a WTP space model. Results show that both altruism and environmental concerns have significant effects on the amount people are willing to pay for changes in forest management. 相似文献
7.
Tree dwelling bats select cavities in large, old, dying or dead trees. This inevitably brings them into direct conflict with the interests of forest managers, who are trained to fell such trees. Therefore the identification of forest stands providing optimal roosting opportunities for bats is crucial, in order to provide appropriate guidelines for forest management. It is also important to identify the extent to which the roosting ecology of bats changes in response to habitat modification. Bia?owie?a Forest (BF) offers a unique opportunity, in the temperate zone, to observe differences between areas with no direct human intervention and managed areas and in particular to reveal the effect of forest management on the roosting ecology of forest dwelling bat species. We used GIS techniques to evaluate bats’ spatial response to changes in forest structure and to test the hypotheses that the forest dwelling bats Nyctalus noctula and Nyctalus leisleri prefer roost sites within old deciduous or wet woodlands over young and coniferous ones and that roost site preferences reflect the extent to which dead and dying trees are removed. There was a significant difference in the selection of roosting habitat between the managed and pristine areas of the forest. Within the pristine forest, both species displayed a strong preference for roost trees located within old deciduous stands (>100 years), whereas in the managed part of the forest old wet woodland was preferred while all medium and young forest stands were avoided. Our data reveal a high degree of lability in the selection of roosting habitat by bats. It appears that bats are able to respond to changes in their environment by changing their roost site preferences and could therefore occupy habitat previously considered less suitable. 相似文献
8.
Forest management, which is the main focus of this paper, is facing fundamental paradoxes and dilemmas that cannot be addressed
by long-term management strategies or management concepts, even where the intention of these strategies is to follow a sustainability
path. On this basis, it is argued that sustainability is not a suitable future-oriented term but rather a term oriented towards
the present. The more complex the relationships between the different social subsystems, the more rapid the social change
of modern societies, the more confusing the present situation and the more unpredictable the future, the less suitable utopian,
long-term strategies and the attitude and strategy of firm decisiveness are to address challenges. Several suggested management
strategies and techniques such as incrementalism, adaptive management and scenario-analysis are critically discussed. The
intention of these strategies is to cope with uncertainty and ignorance. With regard to their limitations, it can be concluded
that strategic decisions in the face of uncertainty have to explicitly consider the reversibility of decisions and the awareness
of their shortcomings in relation to various dimensions of risk, uncertainty and ignorance. It is therefore necessary to look
for modes of planning that actively address uncertainty in organizing learning opportunities and permanent feedback control. 相似文献
9.
Small-scale Forestry - Both the reducing emissions from deforestation and forest degradation program (REDD+) and community-based forest management (CBFM) aim to combat forest degradation and... 相似文献
10.
The functional roles of fungi in recovery of forest ecosystems after fire remain poorly documented. We observed macrofungi soon after fire at two widely separated sites, one in the Pacific Northwest United States and the other in southeastern mainland Australia. The range of species on-site was compared against macrofungi reported after the volcanic eruption at Mount St. Helens, also in the Pacific Northwest. Each of the three sites shared species, particularly representatives of the genus Anthracobia. Soon after disturbance, we noted extensive mycelial mats and masses of fruit-bodies of this genus, particularly at heavily impacted microsites. The mycelial mats appeared to play an important functional role on-site, possibly aggregating soil particles in otherwise highly erodable landscapes. We hypothesise that fungi such as Anthracobia are pivotal species in early system recovery after disturbance, helping minimize the movement of soil in the absence of plant roots. As plant root systems recover, the importance of these fungi in soil stabilization may diminish. Other functional roles of early postfire fungi might include nutrient acquisition, leading to the reestablishment of vegetation. These potential roles need to be experimentally tested and relevant findings incorporated into programs aimed at restoring forest ecosystems after disturbance. 相似文献
11.
A ‘pathways’ and ‘framings’ approach derived from Leach et al. (2010) is used to examine forest sustainability policy in New Zealand. The country has had no comprehensive forest policy since the 1990s and indeed no longer a forest service or its equivalent. Instead ‘forest’ preservation, policy, and monitoring functions are carried out by the Department of Conservation, Ministry of Primary Industry and Ministry of Environment. Exotic plantation forests have themselves been sold off to the private sector and some aspects of planting and harvesting are regulated by the Resource Management Act. Even in this Neo-Liberal setting, and similar to Leach et al.'s work in completely different contexts, policy responses have tended to be oriented towards ‘stability’ and ‘resilience’ types of forest sustainability. Three forest sustainability pathways are evident, directed towards preservation of indigenous biodiversity, economic development without adverse environmental impacts, and monitoring of environmental quality. In some ways the current ‘New Zealand forest governance model’ is an improvement on its predecessor but it seems unlikely to be mobile in a policy sense, resting as it does on the existence a relatively large area of indigenous forest and a large exotic plantation resource where the latter provides all timber needs. 相似文献
12.
This article is a reanalysis of interviews conducted in 2006 and 2009 with forest owners and their families. It gives a complementary interpretation of the forest owners’ decisions to replant spruce despite strong criticism from the public and from experts. The interviewees’ visual conception of the forest landscape and how they relate to it through their forestry practices is analysed. The results show that the forest owners prefer landscapes that are clean and tidy, showing characteristics indicative of forestry skills. At the same time they remain sensitive to the existence of other value systems among the public. The forest owners’ way of looking at the forest was characterized by the fact that they worked with the landscape; for them the forest is not only a symbolic project linked to identity, but also a taskscape, an imprint of performed work. In the discussion, the forest owners’ aesthetic value system is discussed and a supplementary answer is given to why forest owners refused to heed warnings about the replanting of spruce, a question that earlier studies generally attributed to forest owners’ wish to avoid short-term economic risks. 相似文献
13.
For many years, we have observed a significant rise in urban population, the spatial development of cities, and an increase in urbanized areas. More and more people feel the need to have contact with nature. The interest in forest recreation is growing, though the forest is a serious source of allergenic plant pollen. The aim of the present study was to compare two forest types in the context of their recreational potential and the effect strength of aeroallergens. This study was conducted in SE Poland in a Nemoral Scots pine forest (RB) and in a Central European submountainous beech forest (TH). Their recreational potential was assessed. Samples of moss containing plant pollen were collected under the canopy, from forest clearings and forest edges as well as in an open area. Based on the number of pollen grains deposited in moss pollsters, the forest impact on humans was calculated. The recreational potential values for both sites studied are evidence of the high recreational suitability of these forests, but the recreational capacity of RB is lower compared to TH. Palynological analysis showed that the pollen deposition is higher in BR and that the plant pollen risk is lowest under the canopy, regardless of the forest type. The beech forest was found to be characterized by greater recreational potential and a weaker actual effect of pollen allergens than the pine forest. In assessing forest recreational potential, palynological data should form the basis for modification of the degree of recreational suitability. Such information would also be useful in controlling recreational traffic since, as we have proved, visiting appropriate places in a forest allows the exposure of allergen sensitive people to be reduced. 相似文献
15.
The study espoused the access analytical framework to investigate how introduction of Participatory Forest Management (PFM) in Kenya has changed the various actors’ ability to benefit from the forest resources of Eastern Mau Forest Reserve. Data collected through key informant interviews, and a household survey showed that implementation of PFM has triggered new income opportunities for forest adjacent communities in seedling production and beekeeping. However, PFM bestowed no real decision-making powers to the established Community Forest Associations (CFAs) over important forest resources such as timber and firewood. Members of the local communities and other actors have continued to access these resources through various structural and relational means, in the same way as before the introduction of PFM. Further, it is documented that PFM has introduced additional burdens on the local communities, especially the poorest households, as a result of increased enforcement of rules. Based on these findings, it is suggested that the PFM policy in Kenya, in its current form, is unlikely to realize its dual objectives of forest conservation and livelihood enhancement. To attain them would require a further devolution of rights to the CFAs. 相似文献
16.
The present study was conducted in a lowland degraded Quercus remnant forest in northeastern Greece. In 2006, ten plots of 50 m × 50 m were randomly selected in two site types. Site type A is covered by Quercus pubescens– Quercus frainetto stands that are under grazing pressure. In Site type B there are Q. pubescens stands and grazing pressure is more intense. Inside these plots 180 subplots of 2 m × 2 m were established in three regeneration environments and the number of sprouts and seedlings was counted. The three regeneration environments were: (a) rather dense groups of trees, (b) areas with bare soil that alternate with areas with grazed herbs and (c) areas covered only from sparse scattered trees. Moreover the regeneration plants were classed as recently grazed and not recently grazed plants. Six years later, 180 regeneration plants having a height equal to or over 20 cm were selected and were classed as seedlings or sprouts. Sprouts were the dominant form in regeneration. The sprouting ability of Q. pubescens and Q. frainetto seems to be an adaption that enables them to endure grazing. Grazing was the main factor that determined the distribution of regeneration. The ecological differences of the two species do not seem to substantially influence their distribution in the different regeneration environments. It seems that intense grazing keeps the regeneration plants in low height. However, regeneration density can be considered adequate for the perpetuation of the studied stands if the grazing stops. 相似文献
17.
In comparison with integrated pest management and chemical control, the authors put forward a new strategy of forest pest control, named ecological control of forest pest (ECFP). This paper reviewed the development history, summarized the concept and principles of ECFP, discussed the technology and methods of ECFP, and evaluated the ECFP and its application conditions. 相似文献
18.
A plant's induced defense system can be triggered by the application of the plant hormone methyl jasmonate (MeJA), and recent research suggest that MeJA treatment may become a tool for protection of conifer seedlings against insect herbivory (e.g. by the pine weevil Hylobius abietis). A side-effect of MeJA application is temporarily reduced height growth. This has generally been considered as negative, but in forest tree nurseries this could instead be beneficial since it is commonly desired to stop the growth of nursery seedlings in late summer. Artificially longer dark periods (long nights/short days) are widely used in high-latitude nurseries to terminate height growth and induce freezing tolerance. However, long night treatment requires specialized nursery equipment and are labor intensive. Therefore alternatives are sought after. We compared long-night and MeJA treatments by following the growth of Norway spruce (Picea abies) seedlings throughout one season. The regulatory effect of MeJA on height growth was similar if not even better than that of long nights, i.e. it was terminated faster. However, MeJA treatment also reduced root growth and delayed the development of freezing tolerance. MeJA may therefore not replace long-night treatments, but it could facilitate a more flexible application of long nights by gaining a longer time interval during which this treatment can be used without risking the seedlings growing too large. 相似文献
19.
By investigation, the thesis analyses and summarizes the forming and developing of CHFRP In Xupu county. We select the Mayandong stock cooperation forest farm as object, adopt the methods such as semi-structure interview, analysing second data and surveying sample plots, analyse and study the process to clarify the property right, the profits allocated forms and the management forms. The results show that CHFRP can tentatively resolve the contradiction between the forestland using right scattered to every household and proper scale management demanded by forestry production. CHFRP can enhance economic result and stabilize the production form in countryside. The ecological result, economic result and social result of CHFRP are sufficient. 相似文献
20.
INTRODUCTION The present paper summarizes key-results from the analysis and comparison of a sample of (national) statutory forest laws, along with the respective conclusions and recommendations in respect of the forest sector legal reform currently underway in the P.R. China. This study exercise was commissioned by German Technical Cooperation (GTZ), at the request of the Department of Policy and Legislation (State Forestry Administration of the P.R. China – SFA). German Devel op… 相似文献
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