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Towards resource-efficient forests: Mixing species changes crown biomass allocation and improves growth efficiency
Full text linkSocietal Impact Statement
Forests worldwide face significant challenges due to climate change, impacting their health and productivity. In this study, we examined how European beech and Scots pine influence each other's phenology and growth in mixed forests. Our findings indicate that mixing these complementary tree species can increase resource efficiency within forest ecosystems. By leveraging informed species selection, this research highlights the potential for developing knowledge-based, resource-efficient forests. These insights are invaluable for policymakers and forest managers in designing forests that are not only productive but also sustainable and adaptable to evolving environmental conditions.
Summary
We investigated the effects of interspecific neighbors on crown morphology and growth efficiency in European temperate forests, specifically focusing on European beech (Fagus sylvatica L.) and Scots pine (Pinus sylvestris L.). Our goal was to determine whether the previously reported overyielding in this mixture is primarily due to improved space-use efficiency and packing density or enhanced resource-use efficiency.
Our methodology involved a detailed analysis of 128 individual felled trees. We assessed the effect of intraspecific and interspecific neighbors on stem volume growth, the allometric relationships of tree crowns and their components, and the allocation of branch and leaf biomass along the trees' vertical structure.
Our findings demonstrate that interspecific neighbors significantly influence the allometric relationships of tree crowns, especially altering the vertical biomass distribution in European beech. Additionally, we found that interspecific neighbors can significantly enhance the growth efficiency of European beech but not for Scots pine.
This research provides valuable insights for enhancing forest growth models and guiding forest management practices. By understanding the critical role of crown biomass allocation and growth efficiency in mixed-species stands, policymakers and forest managers can design forests that are both productive and adaptable to changing environmental conditions. This study emphasizes the importance of species interactions in forest dynamics and bridges theoretical concepts with practical applications.202
Nurmipalkokasviviljelyn optimointi Pohjois-Pohjanmaan nautakarjatiloilla : OptiPalko
Full text linkRaportti kokoaa yhteen Nurmipalkokasviviljelyn optimointi Pohjois-Pohjanmaan nautakarjatiloilla -hankkeen tutkimusten tulokset. Raportissa keskitytään erityisesti puna-apilan viljelyyn ja rehukäyttöön. Raportissa käsitellään puna-apilan viljelyä puhdas- ja seoskasvustoina eri lannoitustasoilla, puna-apilan säilöntää sekä puna-apilasäilörehun käyttöä loppukasvatettavien sonnien ruokinnassa.
Ensimmäinen tutkimus käsitteli puna-apilan viljelyä kivennäismaalla puhdaskasvustona ja apila-heinäkasviseoksissa eri lannoitustasoilla. Luke Siikajoen tutkimusasemalla Ruukissa vuosina 2021–2023 tehdyssä ruutumittakaavan kokeessa oli timoteitä ja puna-apilaa puhdaskasvustoina ja niiden lisäksi mukana oli timotein ja puna-apilan sekä timotein, nurminadan ja puna-apilan seosnurmet. Typpilannoitustasot olivat 0, 50, 100, 150 ja 200 kiloa typpeä hehtaarille. Nurmet perustuivat hyvin, mutta puna-apila kärsi merkittäviä talvituhoja. Molempina vuosina nurmen kokonaiskuiva-ainesadot lisääntyivät typpitasoon 150 kg/ha saakka. Typen satovaste oli molempina vuosina ensimmäisessä nurmisadossa toista satoa suurempi. Typpilannoitus vähensi selkeästi apilan osuutta seoskasvustoissa. Typpitase oli negatiivinen kaikilla typpitasoilla nurmen ensimmäisen satovuoden kahta korkeinta typpitasoa lukuun ottamatta. Tulosten perusteella typpilannoituksessa kannattaa panostaa ykkössatoon. Kokeessa korostui apilan talvenkestävyyden merkitys. Suuret talvituhot altistivat rikkakasveille. Typen huuhtoutumisriski oli syksyllä mitattujen alhaisten maan epäorgaanisen typen pitoisuuksien perusteella vähäinen.
Toisessa tutkimuksessa keskityttiin puna-apilan säilönnälliseen laatuun. Tutkittavia tekijöitä olivat kasvilaji (puhdas puna-apila, puhdas timotei ja niiden 1:1 seos), säilöntä tuoreena tai esikuivattuna ja eri säilöntäaineiden käyttö (kontrolli ilman säilöntäainetta, heterofermentatiivinen maitohappobakteeriymppi sekä kolme muurahaishappopohjaista säilöntäainetta AIV2 Plus Na, AIV VIA ja AIV OIVA). Sateisen korjuusään vuoksi molempien kasvilajien kuiva-ainepitoisuus tuoreena oli erittäin matala. Esikuivaus tasokuivurissa nosti kuiva-ainepitoisuutta. Sokereita oli niukasti kaikissa säilöttävissä raaka-aineissa, ja säilönnän jälkeen ne olivat kuluneet loppuun kaikista ilman muurahaishappopohjaista säilöntäainetta tehdyistä rehuista. Kasvilajien väliset erot jäivät vähäisiksi. Märkien ilman säilöntäainetta tehtyjen rehujen säilönnällinen laatu oli huono. Esikuivaus ja happosäilöntäaine paransivat säilönnän onnistumista. Puna-apilan säilöntä onnistuu haastavissakin olosuhteissa, kun valitaan oikeat menetelmät. Happosäilöntäaineiden käyttö varmistaa säilöntälaadun erityisesti, jos rehu jää märäksi.
Kolmannessa tutkimuksessa selvitettiin puna-apilasäilörehun tuotantovaikutuksia kasvavien sonnien ruokinnassa. Kokeessa oli 50 simmental-sonnia ja 50 hereford-sonnia. Koe sisälsi kaksi ruokintakoetta, joista ensimmäisessä puna-apilasäilörehua verrattiin timoteisäilörehuun ja toisessa ohrakokoviljasäilörehuun. Säilörehun osuus seosrehun kuiva-aineesta oli 60 %. Molemmissa kokeissa väkirehuna oli ohra. Kokeessa 1 laskettiin tuotantotulosten lisäksi kokeen aikana tuotetun naudanlihan ilmastovaikutus sekä rehevöittävät ja happamoittavat päästöt. Korjuuajan sateisen sään takia puna-apila- ja timoteisäilörehut olivat tavoitetta märempiä ja D-arvot jäivät tavoiteltua matalammiksi. Lisäksi puna-apilan valkuaispitoisuus oli odotettua matalampi. Ohrakokoviljasäilörehun rehuarvot edustivat melko tyypillisiä kokoviljasäilörehujen arvoja. Kokeessa 1 ruokinta ei vaikuttanut sonnien rehun syöntiin eikä tuotantotuloksiin muutoin kuin että puna-apilasäilörehun korvaaminen timoteisäilörehulla lisäsi hieman ruhojen rasvaisuutta. Puna-apilasäilörehun sisällyttäminen ruokintaan vähensi tuotetun naudanlihan ilmastovaikutusta ja rehevöittäviä päästöjä. Kokeessa 2 puna-apilasäilörehun korvaaminen ohrakokoviljasäilörehulla lisäsi sonnien rehun syöntiä ja energian saantia. Parhaat kasvut saavutettiin ruokinnalla, jossa oli puna-apilasäilörehua seoksena ohrakokoviljasäilörehun kanssa. Heikointa kasvu oli ruokinnalla, jossa ohrakokoviljasäilörehu oli ainoana karkearehuna. Muihin tuotantotuloksiin ruokinnalla ei ollut vaikutusta. Puna-apilan suurimmat edut lienevätkin naudanlihantuotannossa lunastettavissa peltoviljelyn kautta typpilannoituksen tarpeen vähenemisen ja viljelykierron monipuolistumisen kautta
Biokiertotaloudesta uusia materiaaleja kaivosten jälkihoitoon
No full textAbstrakti XIII Maaperätieteiden päivillä 7.-8.1.2025 : Terve maaperä ekosysteemipalveluiden tarjoajan
Climate change and nest predation affect shifts in timing and duration of breeding as well as reproductive success in a migratory species
Full text linkWhile it is well known that the overall timing of avian breeding in northern latitudeshas generally advanced due to climate change, it is still unclear how climate warminghas affected the beginning, end, and duration of the breeding period and reproduc-tive success of birds. This is because changes in the phenological breeding metricshave often been studied using ringing data that are based on successful nests only andimpacts of local factors such as nest predation have not been analysed simultaneously.This study used both successful and failed nesting attempts to estimate the annual tim-ing and duration of breeding in common goldeneyes Bucephala clangula. There wasstrong evidence that the beginning of breeding has advanced during 1995‒2022 butonly weak evidence that the end of breeding has advanced. Consequently, the durationof the breeding period lengthened, although statistical evidence for the trend was onlyweak. The relative importance of climate change and nest predation in affecting thetiming and duration of breeding as well as breeding success was also studied. Among-year variation in the beginning of breeding was mainly governed by the timing of icebreakup, an indicator of climate change, whereas nest predation rate in the previ-ous year was the main driver of the end of breeding, the duration of breeding beingaffected by both the timing of ice breakup and nest predation rate. Annual nest-stagesuccess was best explained by nest predation rate. However, final reproductive success(proportion of nest-left ducklings that survived until independence) decreased withadvancing timing of ice breakup, suggesting that climate change has negatively affectedthe production of independent offspring in the study population. The findings of thisstudy underline the importance of also considering local ecological factors when ana-lysing climate change impacts on phenological breeding metrics and breeding successof birds
Formation of Greenhouse Gases in Woodchip Denitrification Treating Aquaculture Effluents : A Case Study
Full text linkWoodchip bioreactors are used to carry out nitrate removal of nutrient-rich aquaculture effluents via denitrification. In certain conditions, greenhouse gases (GHG)s nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2) may be formed which have high global warming potentials (N2O 265 298 times and CH4 28 times that of CO2). This study focused on monitoring the GHGs (N2O, CO2, and CH4) at the woodchip bioreactor, treating the recirculating water of a recirculating aquaculture system (RAS) rearing rainbow trout (Oncorhynchus mykiss) for one year. High nitrate removal (on average 18 g N m-3 d-1, up to 98%) were achieved. The highest rate of N2O removal (ranged from 0 to 45 μg m-2 h-1, 0 13.4 mg CO2-eq m-2 h-1), CO2 (10-450 mg m-2 h-1), and CH4 (from 0.1 to 2.5 mg m-2 h-1, 2.8-70 mg CO2-eq m-2 h-1) were observed in the warmer summer period, likely due to increased microbial actions
Rare fish species in European lakes - patterns and processes
Full text linkAccording to differences in life history and species niches, community assembly processes are predicted to differ between common and rare species. While neutral processes, in particular dispersal, should contribute strongly to assembly of rare species, environmental filtering (species sorting) should dominate the community assembly of common species. We analysed commonness and rarity by occurrence, abundance and geographic range among 82 fish species in 1871 European lakes and reservoirs. The common 25% (21 species) were excluded, and structure and assembly processes of the 75% rare (61 species) species occurring in 348 lakes were evaluated. General linear latent variable models indicated that environmental variables related to lake type (lakes vs. reservoirs), climate and ecosystem size predicted a large proportion of variance for both rare species presence/absence and abundance models, while spatial variables (co-occurrence in watersheds) contributed little to the models. To link community structure with assembly processes, the contribution of seven fish traits related to life history, feeding and habitat preference to predicting the geographic range of the rare species was analysed by boosted regression trees. Intermediate average fecundity and high maximum body length of species predicted smaller geographic range and hence a higher level of rarity, but the response curves of the variables were mostly non-linear and difficult to interpret. In contrast to our assumption, the results of the dominant assembly processes and predictors for rare species were very similar to those predicted for the common fish species in lakes at the continental scale
Boreal temperature variability inferred from latewood maximum density and historical plant phenology records
Full text linkPlant-based data from southern Finland were used to reconstruct late Holocene warm-season temperature variability on inter-annual to longer scales. Temperature-sensitive records representing maximum latewood density of Pinus sylvestris tree rings (since AD 760) and phenological stages of several plant species (since AD 1750) explained ~60% and ~70% of instrumentally observed temperature variance, respectively. The value of a multi-proxy approach was demonstrated by statistical models including both variables, which explained ~80% of the temperature variance. Temperatures from the CRUTEM5 and Berkeley datasets had slight variations in their correlativity with proxy data, possibly resulting from their differing spatial representativeness over the proxy sites. Temperature history inferred from maximum latewood densities extended over the past millennium and correlated with previously published data from similar proxy records in Fennoscandia and adjacent areas. These data indicate that the region cooled since the Medieval Climate Anomaly and warmed markedly since the Little Ice Age/Maunder Minimum. In the study region, the magnitude of this long-term warming was 2.1 °C and 2.8 °C, calculated between the coldest and warmest 100-year and 30-year intervals, respectively. Collectively, our results display the potential of plant-based data from low-lying and mild boreal sites to extend our understanding of preindustrial and recent climatic changes
Root rot increases the vulnerability of Norway spruce trees to Ips typographus infestation
Full text linkNorway spruce (Picea abies) is one of the most economically important tree species in Northern and Central Europe. Root rot caused by Heterobasidion annosum s.l. and the European spruce bark beetle (Ips typographus) are major disturbance agents of Norway spruce and are expected to increasingly affect spruce-dominated forests as the climate warms. This study investigated the direct interaction between root rot and I. typographus, with the aim of examining whether root rot and the stress it causes to a tree increases the risk of subsequent bark beetle attack. In total, 442 Norway spruce trees from nine different mature, even-aged forest stands were studied. First, symptoms caused by I. typographus were evaluated before final felling from each tree based on visual assessments of crown and stem conditions. After the felling, the sample plots were relocated from the clearcut areas, and the stumps of sampled trees were reassessed for root rot. Exploratory analysis and binomial Generalized Linear Mixed Model (GLMM) were used to analyze relationships between explanatory variables and their effect to I. typographus infestation. The best predictors for I. typographus infestation at individual tree level were presence of root rot and to a lesser extent, tree diameter at breast height. Seventy-five percent of root rot-infected trees were also infested with I. typographus, and most of those trees were either dead or severely infested. Results suggest that root rot weakens trees, making them more vulnerable to subsequent I. typographus infestation, especially early in outbreaks when bark beetle population densities are low
Biodiversity
Full text linkThis chapter summarises biodiversity responses to continuous cover forestry (CCF). The comparator throughout this chapter is rotation forestry (RF) and its main harvesting method—clearcutting—unless otherwise stated.
Research on the biodiversity effects of logging methods applied in CCF (mostly selection or gap cutting) mainly concerns the short-term effects of measures taken in mature, originally fairly even-aged forests, at best 10–15 years after cutting. Thus far, no surveys or chronosequences cover the whole rotation period (60–100 years).
Continuous cover forestry is likely to benefit species that suffer when the tree cover is removed, such as bilberry and its associated species. Species requiring spatial continuity in host trees or canopy cover may also benefit.
Selection cutting may preserve the majority of species in the mature forest, but the most sensitive species may decline or even disappear. Gap cutting (diameter 20–50 m) affects forest-interior species relatively little, but species’ abundances in gaps change with increasing gap size. Shelterwood cutting seems to closely resemble selection cutting in terms of species responses. In the long term, however, shelterwood cutting results in an even-aged and sparse overstorey, which does not produce the biodiversity benefits of CCF.
Species that have declined due to forestry mostly require large living and dead trees. The preservation of these species is not ensured by CCF alone, but requires deliberately maintaining these structural features.
A mosaic of different forest-management practices within landscapes may provide complementary ways to maintain rich biodiversity