Browsing by Subject "habitaatti"

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  • Heino, Jani; Koljonen, Saija (2022)
    Ecologial Solutions and Evidence
    1. Freshwater ecosystems and their biota are more seriously threatened than their marine and terrestrial counterparts. A solution to halt increasing negative impacts of anthropogenic development would be to reconsider the basics of nature conservation (i.e. protection of pristine and near-pristine areas) and restoration (i.e. returning an impacted site to as natural condition as possible) through inclusion of the knowledge on abiotic and biotic dynamics of rivers draining pristine catchments. In boreal and Arctic regions, such comparisons are still possible because in addition to harbouring strongly modified drainage basins, some of the most natural drainage basins are also situated in these high-latitude areas. 2. A suitable approach for simultaneous planning of joint river conservation and restoration would be to (i) examine how well different kinds of rivers are covered by existing protected area networks and (ii) to restore parts of degraded rivers to facilitate colonization by aquatic and riparian organisms that have found havens in existing protected areas. This joint approach is a two-way road, as conservation and restoration benefit from each other by allowing river networks to facilitate movements of organisms and matter, thereby mimicking natural riverine meta-systems in anthropogenically modified drainage basins, with restored sites acting as stepping-stones between protected areas. 3. We argue that existing policy instruments should consider the fact that river ecosystems are spatially and temporally dynamic meta-systems. These characteristics should be given due attention in conservation and restoration rather than relying on a static approach where a snap-shot classification of river reaches is thought to be enough without considering underlying ecological dynamics. Taking ecological dynamics into account would contribute to sustainable management and maintenance of biodiversity and ecosystem services.
  • Cantonati, Marco; Poikane, Sandra; Pringle, Catherine M.; Stevens, Lawrence E.; Turak, Eren; Heino, Jani; Richardson, John S.; Bolpagni, Rossano; Borrini, Alex; Cid, Nuria; Cvrtlíková, Martina; Galassi, Diana M. P.; Hájek, Michal; Hawes, Ian; Levkov, Zlatko; Naselli-Flores, Luigi; Saber, Abdullah A.; Di Cicco, Mattia; Fiasca, Barbara; Hamilton, Paul B.; Kubečka, Jan; Segadelli, Stefano; Znachor, Petr (MDPI, 2020)
    In this overview (introductory article to a special issue including 14 papers), we consider all main types of natural and artificial inland freshwater habitas (fwh). For each type, we identify the main biodiversity patterns and ecological features, human impacts on the system and environmental issues, and discuss ways to use this information to improve stewardship. Examples of selected key biodiversity/ecological features (habitat type): narrow endemics, sensitive (groundwater and GDEs); crenobionts, LIHRes (springs); unidirectional flow, nutrient spiraling (streams); naturally turbid, floodplains, large-bodied species (large rivers); depth-variation in benthic communities (lakes); endemism and diversity (ancient lakes); threatened, sensitive species (oxbow lakes, SWE); diverse, reduced littoral (reservoirs); cold-adapted species (Boreal and Arctic fwh); endemism, depauperate (Antarctic fwh); flood pulse, intermittent wetlands, biggest river basins (tropical fwh); variable hydrologic regime—periods of drying, flash floods (arid-climate fwh). Selected impacts: eutrophication and other pollution, hydrologic modifications, overexploitation, habitat destruction, invasive species, salinization. Climate change is a threat multiplier, and it is important to quantify resistance, resilience, and recovery to assess the strategic role of the different types of freshwater ecosystems and their value for biodiversity conservation. Effective conservation solutions are dependent on an understanding of connectivity between different freshwater ecosystems (including related terrestrial, coastal and marine systems).
  • Tolonen, Kimmo T.; Karjalainen, Juha; Hämäläinen, Heikki; Nyholm, Kristiina; Rahkola-Sorsa, Minna; Cai, Yongjiu; Heino, Jani (Springer Link, 2020)
    Aquatic Ecology 54 3 (2020)
    Lake littoral environments are heterogeneous, and different organisms typically show specific responses to this environmental variation. We examined local environmental and spatial factors affecting lake littoral biodiversity and the structuring of assemblages of phytoplankton, zooplankton and macroinvertebrates within and among three basins of a large lake system. We explored congruence of species composition and species richness among the studied organism groups to evaluate their general indicator potential to represent spatial variation in other groups. We expected that effects of water chemistry on plankton assemblages were stronger than effects of habitat characteristics. In contrast, we anticipated stronger effects of habitat on macroinvertebrates due to their mainly benthic mode of life. We also expected that within-basin spatial effects would be strongest on macroinvertebrates and weakest on phytoplankton. We predicted weak congruence in assemblage composition and species richness among the organism groups. Phytoplankton assemblages were mainly structured by the shared effects of water chemistry and large-scale spatial factors. In contrast to our expectations, habitat effects were stronger than water chemistry effects on zooplankton assemblages. However, as expected, macroinvertebrate species composition and richness were mainly affected by habitat conditions. Among-group congruence was weak for assemblage composition and insignificant for richness. Albeit weak, congruence was strongest between phytoplankton and zooplankton assemblages, as we expected. In summary, our analyses do not support the idea of using a single organism group as a wholesale biodiversity indicator.
  • da Silva, Pedro Giovâni; Cañedo-Argüelles, Miguel; Bogoni, Juliano André; Heino, Jani (Frontiers Media S.A., 2021)
    Frontiers in Ecology and Evolution 9: 670212
    According to metacommunity theory (Leibold et al., 2004), the structure of local communities results from the interplay between local factors (e.g., environmental filtering, species interactions) and regional factors (e.g., dispersal rates, landscape configuration). The relative importance of these factors is highly dependent on the organisms’ biological traits, landscape connectivity, and the spatial and temporal scales considered (Heino et al., 2015; Tonkin et al., 2018; Viana and Chase, 2019; Almeida-Gomes et al., 2020; Cañedo-Argüelles et al., 2020; Lansac-Tôha et al., 2021). However, the differences in metacommunity assembly mechanisms found among studies are far from being fully understood. The evaluation of temporal dynamics of metacommunities has only emerged recently (Cañedo-Argüelles et al., 2020; Jabot et al., 2020; Li et al., 2020; Lindholm et al., 2021) and the application of the metacommunity theory in other fields, such as biomonitoring, conservation biology or ecosystem restoration, is yet to be fully explored (Bengtsson, 2010; Heino, 2013; Leibold and Chase, 2018; Chase et al., 2020; Cid et al., 2020; Heino et al., 2021). In this Research Topic, our aim was to invite researchers working in different biogeographic regions and ecological systems (Figure 1) to publish a number of innovative papers on metacommunity spatio-temporal dynamics. We expect to obtain a better understanding of how the factors and processes that structure metacommunities vary in space and time, as well as the implications of such dynamics for biodiversity conservation and ecosystem management.
  • Fourcade, Yoan; WallisDeVries, Michiel F.; Kuussaari, Mikko; Swaay, Chris A. M.; Heliölä, Janne; Öckinger, Erik (John Wiley & Sons Ltd, 2021)
    Ecology Letters 24: 5, 950-957
    Habitat fragmentation may present a major impediment to species range shifts caused by climate change, but how it affects local community dynamics in a changing climate has so far not been adequately investigated empirically. Using long-term monitoring data of butterfly assemblages, we tested the effects of the amount and distribution of semi-natural habitat (SNH), moderated by species traits, on climate-driven species turnover. We found that spatially dispersed SNH favoured the colonisation of warm-adapted and mobile species. In contrast, extinction risk of cold-adapted species increased in dispersed (as opposed to aggregated) habitats and when the amount of SNH was low. Strengthening habitat networks by maintaining or creating stepping-stone patches could thus allow warm-adapted species to expand their range, while increasing the area of natural habitat and its spatial cohesion may be important to aid the local persistence of species threatened by a warming climate.
  • Pykälä, Juha (Elsevier, 2019)
    Global Ecology and Conservation 18 (2019), e00610
    Why populations of threatened species disappear is among the key questions in conservation biology. However, very few local and regional studies have attempted to quantify the importance of the various causes. In this investigation, the status of the populations of threatened vascular plants, bryophytes and lichens found between the years 1860–1979 in a national biodiversity hot spot in SW Finland was studied during the years 1990–2008. Of the populations, 82% had disappeared and 18% were re-discovered. The disappearance rate of populations differed between habitats: exceeding 80% in most habitat types whilst being lowest on rock outcrops (58%). Complete destruction of all locally suitable habitats was the main reason for the disappearance of the populations (73%) concerned. Habitat deterioration (including partial habitat loss) was identified as the reason for the disappearance for 22% of the populations. Only for 5% of the populations could it not be revealed whether habitat quality had changed or not, but deterioration of habitat quality or habitat loss is possible even in these cases. For none of the disappeared populations was no change in habitat quality verified. In most cases, habitat loss and deterioration were caused by agriculture or forestry. These results support the conclusion that vascular plant, bryophyte and lichen populations in the boreal landscape have disappeared directly because their habitats have disappeared, declined in size or deteriorated due to forestry, agriculture, construction, mining and pollution. More subtle changes in habitat quality, fragmentation, problems related to small population size per se and other reasons may have contributed to only a few disappearances of local populations. The disappearance rate was similar between the study groups, but the relative importance of reasons for disappearance was different. The results emphasize the importance of habitat protection for threatened vascular plants, bryophytes and lichens.
  • Sauramo, Virva (Helsingin yliopisto, 2019)
    Boreal lakes and wetlands that are abundant in the world are vital breeding and resting areas for birds. However, a significant part of wetlands has been globally lost due to human activity. In the study area of this research, Evo, lake habitats are somewhat stable especially in landscape level, changes are mainly lake-specific. Habitat use and its stability have been studied earlier on other bird species, such as ducks (Anas spp.) but little research exists about the matter on wader or shorebird species. This study aimed to compare the patch-scale habitat use stability of two waders; Common Sandpiper (Actitis hypoleucos) and Green Sandpiper (Tringa ochropus). The comparison was also made between the pair densities of these species. Many species are known to benefit from beaver induced floods. However, previous studies have not measured the effect of beaver before, during and after beaver flooding. Therefore, this study aimed to investigate the presence and abundance of Green Sandpiper at different stages of beaver flood. This study showed that the habitat use of Common Sandpiper was more stable than that of Green Sandpiper, although both species showed variation. Pair density of Common Sandpiper was lower than Green Sandpiper’s nearly throughout the study period. Pair density of Common Sandpiper, on the contrary, showed more variation compared to Green Sandpiper’s pair density. Green Sandpipers were observed in nearly all of the beaver ponds in this study. Presence and abundance of Green Sandpiper were highest during the beaver flood, but the numbers stayed high also after the flood. It could be concluded that Common Sandpiper is a species of high site-fidelity and more prone to changes in the environment than Green Sandpiper, which seems to be able to utilize variable habitats, such as flowages regularly created by beaver in the Evo region. In previous studies, many species have been known to benefit from beaver activity, and Green Sandpiper can be seen as a species of plastic habitat use and being able to profit from surroundings altered by beaver. Therefore, this wader benefits notably from beaver floods.
  • Lahtinen, Jonna (2002)
    Opinnäytetyössä pohditaan kysymystä "miksi haluan olla kaikkien kanssa kaiken aikaa kaikkialla" sinkkunaisten kännykänkäytön näkökulmasta. Teemahaastattelujen avulla kysymystä on tarkasteltu sinkkuna olevien nuorten naisten kännykänkäytönkontekstissa. Lisäksi on pohdittu sitä, millä tavoin kännykkäriippuvuus liittyy tähän Elisa Communicationsin käyttämään mainoslauseeseen. Kännykänkäyttö liittyy nykypäivänä saumattomasti lähes jokaisen ihmisen arkeen. Olemme huomaamattomasti tulleet riippuvaisiksi matkapuhelinten tarjoamasta mahdollisuudesta olla "joka paikassa kaiken aikaa ja kaikkien kanssa". Kännykänkäytön merkitys näkyy niin arjen parempana halittavuutena kuin sosiaalisten suhteiden tasollakin. Tehtyjen teemahaastattelujen perusteella voidaan todeta kännykän merkityksellistyvän eri tavalla sinkkuus- kuin parisuhteessa elävien kontekstissa. Työssä tarkastellaan aikalaiskuvauksissa käsiteltyä aihetta sosiaalisten suhteiden ja ihmisten välisen kanssakäymisen laadullisesta muutoksesta, johon kiihtyvä elämän teknologisoituminen on vaikuttanut. Mitä meille kertoo kasvavat avioerotilastot ja avoliittojen yleistyminen? Entä se, että yksinasuvia on Helsingissä jo niin paljon, että se on alkanut vaikuttaa asuntotuotantoon? Millaista julkisuuskuvaa media, kuten TV, elokuvat ja lehdet tuottavat "ajan hengestä" ja "sinkkuusdiskurssista"? Sosiaalisissa suhteissa tapahtunutta muutosta tarkastellaan sosiologisen aikalaisanalyysin kuten Zygmunt Baumanin, Anthony Giddensin sekä Ulrich Beckin pohtimien teemojen valossa. Työssä tehdään eräänlainen läpileikkaus kyseisten ajattelijoiden ajatuksiin ja niiden tarjoamien teoreettisten käsitteiden mahdollisuuksiin tehdä sosiaalipoliittista tutkimusta. Usein sanotaan, että aikalaisanalyysejä ei tulisi käyttää teoreettisena viitekehyksenä, koska teoreettisen ja empiirisen välinen kytkös saattaa muodostua liian hataraksi. Kuitenkin tähän "haasteeseen" on haluttu ottaa kantaa tutkimalla, kuinka empiirisesti kestäviä aikalaisdiagnostisen keskustelun tarjoamat ajatuskonstruktiot ovat. Tutkielman kiteyttävä ajatus on se, kuinka kännykkään "sisäänrakennettu" velvoite olla aina tavoitettavissa synnyttää vastareaktiona tarpeen oman henkilökohtaisen ajan ottamiselle. Tämä korostuu sinkuilla, joilla kännykänkäytön freksvenssi on suurempi kuin parisuhteessa elävillä. Herättääkö teknologian tuottama informaatioähky itse asiassa kysymyksen siitä, miksi en halua olla kaikkialla kaikkien kanssa kaiken aikaa.
  • Kittamaa, Sanna; Ryttäri, Terhi; Ajosenpää, Terhi; Aapala, Kaisu; Hallman, Erkki; Lehesvirta, Timo; Tukia, Harri (Suomen ympäristökeskus, 2009)
    Suomen ympäristö 25/2009
    Harjumetsien paahdeympäristöt ja niillä elävä erikoistunut ja uhanalaistunut eliölajisto ovat viimeisten vuosikymmenten aikana vähentyneet suuresti muun muassa metsäpalojen loppumisen ja yleisen rehevöitymiskehityksen vuoksi. Harjumetsien paahdeympäristöjen nykytila ja hoito 2006 - 2008 -hankkeessa koottiin kattava harjumetsien metsätaloutta ja suojelua edustava yhteistyöverkosto, johon kuuluivat SYKEn luontoasiantuntijoiden lisäksi Metsätalouden kehittämiskeskus Tapio, 10 metsäkeskusta (2008), Metsähallituksen metsätalous ja luontopalvelut, UPM-Kymmene sekä Helsingin yliopisto. Hankkeessa etsittiin jäljellä olevia, hoitotoimin parannettavia paahde­ympäristöjä ja käynnistettiin niillä sekä hoitotoimia että erilaisia koejärjestelyjä, joiden avulla hoitojen onnistumista voidaan arvioida. Hankkeen aikana inventoitiin yhteensä noin 30 000 hehtaaria harjumetsää, joista suurin osa sijaitsee Natura 2000 -alueilla. Löydettyjen, hoitokohteiksi soveltuvien paahdekohteiden yhteispinta-ala on noin 120 hehtaaria. SYKEn tutkijoiden inventoimalta 14 200 hehtaarin alueelta löydettiin noin 1,7 hehtaaria luonnontilaista tai lähes luonnontilaista paahdekohdetta. Tämä on vain noin 3 % löydetystä 52 hehtaarin paahde­alasta. Täten lähes kaikki inventoinneissa löydetyt kohteet olivat enemmän tai vähemmän umpeenkasvaneita ja niiden tilaa on perusteltua parantaa hoitotoimin. Tulosten perusteella paahdeympäristöjen hoito pystytään toteuttamaan myös kustannustehokkaasti normaalien metsänhoitotoimien ohessa eikä se välttämättä ole ristiriidassa metsätalouden tavoitteiden tai esimerkiksi maisemansuojelun kanssa. Työ on saanut myös sekä maanomistajien että suuren yleisön tuen. Yhteistyöverkosto on ollut aktiivisesti keskusteleva ja se on onnistunut luomaan innostuneen ja kannustavan ilmapiirin ja yhteisön, jonka yhteisenä tavoitteena on ollut ja tulee jatkossakin olemaan uhanalaistuneen harjulajiston pelastaminen.
  • Heikkinen, Risto K.; Kartano, Linda; Leikola, Niko; Aalto, Juha; Aapala, Kaisu; Kuusela, Saija; Virkkala, Raimo (Elsevier, 2021)
    Global Ecology and Conservation 28, e01664
    The Habitats Directive of the European Union is a key legislative instrument in Europe, supporting the conservation of rare, threatened or endemic species. It aims at ensuring that the species listed in the Annexes of the Habitats Directive show a favourable conservation status, i.e., that they are able to maintain viable populations and that their natural range is sufficient and not decreasing currently, nor will in the future. However, climate change may hamper Habitats Directive species in achieving (or maintaining) a favourable conservation status, particularly when these impacts are amplified by adverse land use. Here, we studied Habitats Directive species in Finland for which ≥70% of the occurrences were recorded with the resolution of ≤100 m. The number of occurrence sites for the 52 species studied ranged from one site to 13,653 sites, summing up to 19,367 sites. For all these sites and their surroundings, we assessed the vulnerabilities caused by climate change and land use. The climate exposure of occurrence sites was measured based on the rapidity of climatic changes (i.e. climate velocity) in three climate variables (growing degree days, mean January air temperature, water balance) at each site. Risks caused by land use were assessed using two negative and four positive variables that respectively described the quantity of land cover and habitats that is either harmful (e.g. clear-cut forest and drained peatlands) or supportive (protected areas and suitable habitats) to species occurrences. To complement climate and land-use variables, three additional variables describing protection status of the sites and the number of occurrences of the same species in the landscape were examined. Comparison of the mean vulnerability values for each species showed that some of the species inhabit, on average, areas with high climate exposure. Moreover, in certain species climate change-induced vulnerabilities consistently coincide with negative land use. However, in many of the 52 species there was large variation in the vulnerability levels between individual occurrence sites, concerning both climate exposure and land-use variables. Considering the vulnerabilities due to climate change separately, 40–60% of the species occurrence sites are expected to face high exposure caused by rapid changes in summer or winter temperatures, which presents challenges in maintaining a favourable conservation status. Our results also revealed numerous species occurrences where high climate velocity coincided with a large amount of negative land use and low amount of suitable habitat, for which climate-wise conservation planning could be targeted.
  • Määttänen, Aino-Maija; Virkkala, Raimo; Leikola, Niko; Heikkinen, Risto K. (Springer Science and Business Media LLC, 2022)
    Ecological Processes
    Background Protected areas (PA) are central to biodiversity, but their efficiency is challenged by human-induced habitat loss and fragmentation. In the Fennoscandian boreal region, forestry with clearcutting is a threat to biodiversity causing the loss of mature forest elements and deterioration of ecological processes in forest landscapes, ultimately affecting PAs via declined structural connectivity. This paper aims to (1) determine PAs with high, red-listed species concentrations; (2) estimate the change in forest habitat around these PAs on different spatial scales; and (3) determine if forest management intensity is higher around biologically most valuable PAs. Occurrences of red-listed forest-dwelling species in Finland were used to identify PAs harbouring these species and to produce site-specific importance indices. CORINE landcover data was used as a baseline for the distribution of forests to assess the cover of clear-cuttings from 2001 to 2019 with the Global Forest Change (GFC) data set in three buffer areas around the PAs with occurrences of red-listed species. Results The largest proportion of clear-cuts occurred in 1 km and 10 km buffers around the PAs in the southern and middle boreal zones, being ca. 20%. This indicates that the forest habitat is degrading fast at regional and landscape levels. On the positive side, the change in forest cover was lower around the biologically most important PAs compared to other PAs with red-listed species. Conclusions Open and free satellite-data based assessments of the cover and change of forests provide reliable estimates about the rates at which mature and old-growth forests are being converted into young managed ones in Finland mainly via clear-cuts on different scales around PAs. The rate of clear-cuts was lowest in adjacent buffer areas next to the most species-rich PAs, which provides opportunities for biodiversity conservation efforts to be targeted to the remaining mature and old-growth forests found in the vicinity of these areas.
  • Saaristo, Lauri (University of Helsinki, 1999)