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Mikko Mönkkönen Pasi Reunanen Janne S. Kotiaho Artti Juutinen Olli-Pekka Tikkanen Jari Kouki 《European Journal of Forest Research》2011,130(5):717-727
Setting aside parcels of land is the main conservation strategy to reduce the rate of biodiversity loss worldwide. Because
funding for biological conservation is limited, it is important to distinguish the most efficient ways to use it. Here, we
assess implications of alternative measures to conserve biodiversity in managed boreal forest landscapes. We calculated four
alternative spatio-temporal scenarios and compared these to the current management regime over 100-year time period. In the
alternative scenarios, a fixed amount of funding was invested in (1) permanent large reserves (each tens of ha in size), (2)
permanent small reserves (each a few ha in size), (3) temporary small reserves (based on 10-year contracts with private land
owners), and (4) green-tree retention (small groups of trees retained on clear-cuts). To assess biodiversity implications,
we used habitat suitability indices to calculate overall habitat availability for five groups of red-listed and habitat-specific
species associated with decaying spruce logs. The possibilities for timber harvests did not differ among the scenarios, but
biodiversity performance was different. The scenarios with permanent reserves tended to outperform other scenarios, suggesting
that conservation policies based on permanent reserves are the most cost-efficient in the long term. Results, however, varied
among time scales and species groups. In the short term, a strategy of investment in temporary small reserves was the most
efficient. Habitat for species associated with old spruce dead-wood and preferring shade was rare throughout all simulations,
and therefore, it is likely that these species cannot be sustained in managed forests. Species that live on fresh dead-wood
and are associated with forest edges coped well in all scenarios suggesting that such species will persist in managed landscapes
without additional conservation efforts. Explicit definition of conservation objectives and time frames for conservation action
are thus prerequisites for successful conservation planning. 相似文献
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This paper examines the historical phases of Finnish forest planning from the 1960s to the present day in support of the rational
future development of forest planning for family-owned forest holdings. The ‘historical types’ of work—craft work, mass production,
process enhancement, and mass customization have been recognized in the Finnish planning discourse to date. Indications of
mass customization are typical in the present developmental discussion of forest planning. There are some signals in the current
planning debate that are calling for the next activity principle, co-configuration. A forthcoming type of forestry extension
activity, labelled adaptive planning, is described in this paper to explicate the demands imposed by a future planning system.
The present analysis informs also other contexts outside of Finland, where public and private institutions that support family
forest owners face post-industrial challenges. 相似文献
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Olli-Pekka Tikkanen Tero Heinonen Jari Kouki Jukka Matero 《Biological conservation》2007,140(3-4):359-372
Understanding of how a large landscape or network of conservation areas and habitats of red-listed species change in time is an important topic when addressing the temporal interplay between protected areas and matrix. We developed models of habitat suitability indices (HSI) for saproxylic red-listed invertebrate and fungal species, accounting for roughly 70% of all red-listed boreal forest species of the study area in eastern Finland. By using a forestry planning program that incorporates various optimisation methods we analysed trade-offs between timber production and amount of habitats of saproxylic red-listed species within a 60-year period. We also produced production possibility frontiers that show how to increase quality of the matrix with least costs. Moreover, we analysed how habitat suitability criteria used in optimisations affect the area of different habitat quality classes.
Our analysis shows that by adopting HSI models in long-term matrix management, it is possible to increase habitats for several red-listed species without substantial losses in timber production. The increase in habitat area is achieved mainly by decreasing the area that is thinned compared to intensive timber production plan. In the long term, this seems to be a novel cost-effective method to increase the quality of the matrix for red-listed saproxylic species. However, the selected optimisation method and the criteria or specification of the management objective for red-listed forest species have a strong effect on results when HSI models are used in conservation planning. Therefore any practical application must be performed with great care. 相似文献
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Importance of dose metrics for lethal and sublethal sediment metal toxicity in the oligochaete worm Lumbriculus variegatus 总被引：2，自引：2，他引：0
Olli-Pekka Penttinen Johanna Kilpi-Koski Maritta Jokela Katri Toivainen Ari Väisänen 《Journal of Soils and Sediments》2008,8(1):59-66
Background, Aims, and Scope There is an increasing demand for controlled toxicity tests to predict biological effects related to sediment metal contamination.
In this context, questions of metal-specific factors, sensitivity of toxicity endpoints, and variability in exposure duration
arise. In addition, the choice of the dose metrics for responses is equally important and is related to the applicability
of the concept of critical body residue (CBR) in exposure assessments, as well as being the main focus of this study.
Methods Experiments were conducted to assess toxicity of Cd, Cr, Cu and Pb to the oligochaete worm Lumbriculus variegatus with the aim of determining CBRs for two response metrics. Mortality and feeding activity of worms exposed to sediment-spiked
metals were used as end-points in connection with residue analyses from both the organisms and the surrounding media.
Results LC50 values were 0.3, 1.4, 5.2, and 6.7 mg/L (from 4.7 μmol/L to 128.0 μmol/L), and the order of toxicity, from most toxic
to least toxic, was Cu > Cd > Pb>Cr. By relating toxicity to body residue, variability in toxicity among the metals decreased
and the order of toxicity was altered. The highest lethal residue value was obtained for Cu (10.8 mmol/kg) and the lowest
was obtained for Cd (2.3 mmol/kg). In the 10-d sublethal test, both time and metal exposure were an important source of variation
in the feeding activity of worms. The significant treatment effects were observed from worms exposed to Cd or Pb, with the
controls yielding the highest feeding rate. However, quantitative changes in the measured endpoint did not correlate with
the exposure concentrations or body residues, which remained an order of magnitude lower than in the acute exposures.
Discussion Both response metrics were able to detect a toxic effect of the metals. However, the ranking of metal toxicity was dependant
on the choice of the dose metric used. An attempt to form a causal mortality-mediated link between tissue residues and metal
toxicity was successful in water-only exposures. The results also indicated that egestion rate was a sensitive toxicity end
point for predicting the effects of sediment contamination.
Conclusions By relating the biological response with the tissue metal residues, toxicity data was comparable to both environmental media
as well as different response metrics and time scales. The results also revealed the importance of metal toxicity ranking
on a molar basis and, furthermore, a direct link to the CBR concept was established.
Recommendations and Perspectives There is a growing demand for methods to assess the effects of contaminated sediments to benthic fauna and whole aquatic ecosystems.
Such information is needed for sediment quality guidelines that are currently being developed in many countries and remediation
processes. The use of body residues as a dose metric in metal toxicity studies may help to overcome difficulties related to
bioavailability issues commonly faced in sediment toxicity studies.
ESS-Submission Editor: Prof. Dr. Henner Hollert (henner.hollert@bio5.rwth-aachen.de) 相似文献
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Olli-Pekka Tikkanen Anna Ruokolainen Raimo Heikkilä 《Scandinavian Journal of Forest Research》2014,29(2):152-161
Regeneration of natural forest structures and dead wood has a key role in the long-term maintenance of biodiversity in most parts of the boreal zone. In order to obtain benchmarks for practical dead wood management rapidly, we utilised unintended historical experiments in land use by studying the recovery of forests surrounding abandoned villages along 2.5-km transects in NW Russia. The signs of past human forest use declined as a function of distance from villages. We found that the closest forests were 130 yr old or younger and contained very few elements typical of natural forests. Forests at a distance of between 1 and 1.5 km were older than 150 yr but showed marks of selective cuttings and had a less complete continuum of dead wood than forests that were 2–2.5 km from the villages. The most remote stands, which were generally older than 200 yr, predominantly had no signs of past forest use and had the most diverse dead wood composition. Our study shows that full recovery of the dead wood continuum in middle boreal forests is a slow process and also that less intensive past forest use can have a significant effect on the dead wood continuum. 相似文献
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In the early summer of 1987 an untimely needle loss was observed in Scots pine (Pinus sylvestris L.) of different ages growing on oliogotrophic mineral soils in Cladina and Calluna-type heath forests in northern Finland.
The first symptoms were observed at the beginning of July when current shoot growth was ending and the young needles were
flushing. The older needles first yellowed then later turned brown before falling. Needle loss proceeded from the oldest to
the younger needle age classes. The trees lost between one and four age classes of needles from earlier growth and retained
only the most recent 1 to 3 yr needles. Foliar analysis indicated nutrient stress as revealed by retranslocation of mobile
nutrients such as N and insufficient uptake of immobile nutrients such as Ca. The soil nutrient concentration, however, was
normal at poor sites and therefore it appears the primary reason for needle Loss is a nutrient stress due to root damage.
This damage was caused by unusual weather in the winter of 1986 to 1987, rather than by soluble Al. 相似文献
8.
In the early summer of 1987 an untimely needle loss was observed in Scots pine (Pinus sylvestris L.) of different ages growing on oliogotrophic mineral soils in Cladina and Calluna-type heath forests in northern Finland. The first symptoms were observed at the beginning of July when current shoot growth was ending and the young needles were flushing. The older needles first yellowed then later turned brown before falling. Needle loss proceeded from the oldest to the younger needle age classes. The trees lost between one and four age classes of needles from earlier growth and retained only the most recent 1 to 3 yr needles. Foliar analysis indicated nutrient stress as revealed by retranslocation of mobile nutrients such as N and insufficient uptake of immobile nutrients such as Ca. The soil nutrient concentration, however, was normal at poor sites and therefore it appears the primary reason for needle loss is a nutrient stress due to root damage. This damage was caused by unusual weather in the winter of 1986 to 1987, rather than by soluble Al. 相似文献
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Olli-Pekka Tikkanen Jukka Matero Mikko M?nkk?nen Artti Juutinen Jari Kouki 《European Journal of Forest Research》2012,131(5):1411-1422
Maintenance of biodiversity in commercial forests has become a main goal in forestry, and several new management principles to reach that goal have been introduced lately. For example, in even-aged forestry, tree retention (leaving a proportion of trees standing in clear-cut sites) is widely used to increase the structural diversity and the amount of dead wood in forests. However, the cost-efficiency of the new management principles is poorly studied. To increase the amount of dead wood, an alternative way could be a change in the thinning regime, so that the self-thinning builds up of woody debris of a growing stand. We used long-term (200?years) simulations to compare ecological and economical effects of the two alternative management practices to increase the amount of dead wood in forest stands: (1) green tree retention and (2) growing stands unthinned. We simulated stand growth and management of 12 pine and 12 spruce stands that represented sites in different parts of Finland. We found that growing stands unthinned produced about 5–6?times more dead wood than retention with 20 trees left per hectare. In terms of economical loss, leaving stands unthinned reduced the net present value of harvest revenues less than 20%. Consequently, leaving stands unthinned offers a cost-effective option to increase the amount of dead wood in commercial forests. The effects of unthinned management were, however, dependent on thermal sum and initial stand density, indicating that biodiversity-oriented management practices should be designed for local conditions. 相似文献
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Olli-Pekka Tikkanen Olga Predtechenskaya Anna Ruokolainen Raimo Heikkilä 《European Journal of Forest Research》2017,136(5-6):827-837
Information concerning the speed of recovery in forest ecosystems is critical when seeking to determine the length of sustainable logging rotations, or for the evaluation of different forest restoration options for species conservation programs. Different functional groups may have specific roles within the ecosystem processes and costly conservation efforts should be targeted at species of conservation concern. Therefore, an analysis of how functional or ecological groups recover following disturbance could provide more precise information than the recovery of taxonomic groups alone. We studied the recovery rate of taxonomic and functional groups of fungi in a boreal landscape where forest use had ceased more than 60 years ago. The forests in our study areas had a variable utilization history. The stands located near abandoned settlements were former scrubland. The adjacent stands formed a selectively cut zone and were followed by stands deeper in the forest matrix that were largely in pristine condition. We recorded boletoid, agaricoid and aphyllophoroid fungi species numbers in 0.25 ha sample plots at 500 m intervals along seven 2–2.5 km long transects. The transects started at the edge of the forest next to the abandoned settlements. Distance (intensity of previous forest utilization) did not affect the species richness of the taxonomic or functional groups of fungi, although the number of aphyllophoroid species of conservation concern was 50% lower in the forests that had been utilized in the past than in the surrounding pristine forests. Moreover, in stands close to the villages, the composition of aphyllophoroid species (β diversity) differed from that of more distant and less utilized stands. Our results would suggest that the majority of ecosystem properties provided by higher fungi groups seem to recover within one century. However, the slow pace of accumulation of dead wood in an advanced state of decay probably slows the recovery of aphyllophoroid species of conservation concern. 相似文献