Metsakuivenduse mõju bioloogilisele mitmekesisusele ja elupaikadele: järeldused säästlikuks majandamiseks ja looduskaitseks

Väitekirja elektrooniline versioon ei sisalda publikatsioone.Töö koondab senised teadmised metsakuivenduse mõjust elurikkusele, hinnates selle pikaajalist toimet elupaigaomadustele ja liikidele ning juhendab, kuidas kuivendamist elustikku säästvamalt korraldada. Kuivendamist rakendatakse laialdaselt metsa tootlikkuse suurendadmiseks. Selle keskkonnamõjudele on aga, nt raiega võrreldes, vähe tähelepanu pööratud. Pärast kraavide kaevamist, toimuvad ökosüsteemis mitmesugused muutused, mis ökoloogiliste ja sotsiaalmajanduslike tagasisidemehhanismide tõttu on suuresti pöördumatud. Pikaajalise kuivenduse tagajärjel korralduvad sadade liikide asurkonnad ümber, nii leidsime, et vähemalt viiendikule lodumetsa liikidest on kuivendus kahjulik, kuid nende asemele levib umbes sama palju uusi liike. Kuivenduse mõjud on suuresti viibega ja kaudsed, toimides näiteks puistuga seotud mikroelupaikade aeglase muutumise kaudu. Puistu struktuuri muutumise suhtes olid eriti tundlikud samblad ja samblikud . Kuivenduse mõju neile saaks leevendada suurendades puistu mitmekesisust ja lamapuude hulka. Kuivendatud metsad polnud üheselt vaesunud, vaid neis leidus väärtuslikke elupaigakomponente ja tänu sellele ka ohustatud liike. Näiteks ei paistnud kuivendus väikeste veekogude üldhulka vähendavat, küll aga muutis nende omadusi – looduslikud väikeveekogud asendusid osaliselt kraavidega. Metsaaladel laialt levinud inimtekkelised veekogud, nagu kraavid ja rattarööpad, pakuvad mitmekesiseid elupaiku, sobides täiendama looduskaitsevõtteid. Viimased on aga tulemuslikud kui need suunata võimalikult paljudele sarnase nõudlusega liikidele ning kõige tõhusamatesse paikadesse maastikul. Töös kirjeldatakse süsteemset lähenemist metsakuivenduse ühendamiseks looduskaitse eesmärkidega. Selleks tuleb maastikust lähtuvalt valida elustiku sihtrühm, piiritleda suunisliigid ning jaotada ruumis erinevad majandamisvõtted, et tagada nii puidutootmine kui ka elustiku säilimine  This thesis integrates the present knowledge on the impacts of forest drainage on biodiversity, assess the long-term impact of the drainage on habitat quality and species assemblages, and gives implications, how to harmonize ditching practices with sustainable management. Forest drainage manipulates the key components of the ecosystem – hydrology and dominating organisms (trees, Sphagnum mosses) – and consequently the whole biota and ecosystem functioning. Forest drainage is practised in vast areas to increase timber production. Its environmental impacts, yet, have gained little attention, compared to e.g. effects of harvesting. The harpoon heuristic depicts the post-drainage transformation of the ecosystem. After the initial stick – i.e. the ditching – the harpoon penetrates deeper pressing its barbs ( i.e. irreversible changes) one after another into the ecosystem. The irreversibilities are caused by several ecological and socio-economical feedback mechanisms. During the long-term draining, populations of hundreds of species reorganize. For example, drainage is detrimental for at least one fifth of the species in swamp forests, though about the same number of new species colonizes the area after drainage. A large part of drainage impacts are delayed and indirect, functioning via slowly changing forest structure. Lichens and bryophytes were especially sensitive to the latter. Thus the impact of forest drainage could be mitigated by increasing the diversity of overstory and abundance of logs. Drained forests were not unambiguously impoverished, but contained valuable habitat components and therefore also threatened species. For example drainage did not seem to decrease the overall amount of small water bodies, though it did change their features – natural water bodies were replaced with ditches. Widespread anthropogenic water bodies, such as ditches and wheel rut pools provide varied habitats, thus could complement local restoration and conservation attempts. The latter are effective if targeted to multiple species with similar habitat requirements, and to key sites in the landscape. In the thesis a systematic approach for harmonizing forestry ditching practices with the aims of biodiversity protection is described. According to this, representative ‘focal species’ from sets of sensitive species should be selected, depending on landscape context and the stands allocated into four main groups of management approaches. Hundreds of species should be examined to identify a few representative biodiversity targets for drainage mitigation programmes. Some bryophytes and lichens growing on live and dead trees were provided as representatives of the biota of natural swamp forest. The general implications based on this thesis suggest paying more attention to the impacts of forest drainage on biodiversity and applying appropriate mitigation measures according to landscape context. The further research to support biodiversity conservation practises includes assessing less studied but potentially sensitive species groups, details of the impact mechanisms, searching for and testing of focal-species and habitat management approaches

Habitat Models of Focal Species Can Link Ecology and Decision-Making in Sustainable Forest Management

A fundamental problem of sustainability is how to reduce the double complexity of ecological and social systems into simple operational terms. We highlight that the conservation concept of focal species (selected species sensitive to a set of anthropogenic threats to their habitat) links multiple issues of ecological sustainability, and their habitat models can provide a practical tool for solving these issues. A review of the literature shows that most spatial modeling of focal species focuses on vertebrates, lacks the aspect of aquatic and soil habitats, and has been slow in the uptake by actual management planning. We elaborate on a deductive modeling approach that first generalizes the main influential dimensions of habitat change (threats), which are then parameterized as habitat quality estimates for focal species. If built on theoretical understanding and properly scaled, the maps produced with such models can cost-effectively describe the dynamics of ecological qualities across forest landscapes, help set conservation priorities, and reflect on management plans and practices. The models also serve as ecological hypotheses on biodiversity and landscape function. We illustrate this approach based on recent additions to the forest reserve network in Estonia, which addressed the insufficient protection of productive forest types. For this purpose, mostly former production forests that may require restoration were set aside. We distinguished seven major habitat dimensions and their representative taxa in these forests and depicted each dimension as a practical stand-scale decision tree of habitat quality. The model outcomes implied that popular stand-structural targets of active forest restoration would recover passively in reasonable time in these areas, while a critically degraded condition (loss of old trees of characteristic species) required management beyond reserve borders. Another hidden issue revealed was that only a few stands of consistently low habitat quality concentrated in the landscape to allow cost-efficient restoration planning. We conclude that useful habitat models for sustainable forest management have to balance single-species realism with stakeholder expectations of meaningful targets and scales. Addressing such social aspects through the focal species concept could accelerate the adoption of biodiversity distribution modeling in forestry

Teejuht püsimetsandusse

Selle kirjatöö peamine eesmärk on, nagu pealkirigi ütleb, teed juhatada. Teekonnale on oodatud kõik, kes soovivad end mitmesuguste looduslähedaste metsa majandamise võtetega kurssi viia. Kuigi retk võiks pakkuda huvi eelkõige metsandustudengitele ja -õppejõududele, metsaomanikele, -majandajatele ja -korraldajatele, ei tasuks siiski saapaid nurka visata ka tavakodanikul kui riigimetsa omanikul. Püsimetsandusest on küll siin-seal ka eesti keeles kirjutatud, nt Karoles 1995a, Tullus 2012, kuid senise käsitluse põgususe või unustusehõlma vajumise tõttu võib metsaomanikule olla jäänud ekslik mulje, et metsamajandamine ongi mustvalge: majandatakse kas intensiivselt lageraietega või ei majandata üldse. Kuid võimalusi on rohkem ja käesolev ülevaade tahabki tähelepanu juhtida ühele vahepealsetest võimalustest, püsimetsandusele. Lühidalt öeldes seisneb püsimetsamajandus raietel üksikpuude või väikeste puudesalkade eemaldamises. See on puidutootmise valdkonna mõiste. Ka selles kirjatöös on rõhuasetus puidutootmisel ning metsa mittepuidulisi väärtusi on käsitletud eelkõige kaasnähtusena. Levinud arusaama järgi võiks püsimetsandus sobida esmajoones väikemetsaomanikule, kes tahab oma metsast tarbe- ja küttepuitu varuda ning kellele on oluline, et kodumets alaliselt säiliks. Siiski pole selline oma perele puude varumine püsimetsa ainus kasutusvõimalus. Oskuslikult oma tegevust kavandades ja loodusega koostööd tehes võib püsimetsandus osutuda heaks lahenduseks ka suuromandites. Kuigi püsimets ei sobi kõikidele põlismetsade elanikele, näiteks mitmetele kõdupuiduliikidele, sarnaneb see siiski mõneti põlismetsaga: puud on erineva vanusega, leidub pimedamaid ja päikselisemaid laike, mitmesuguseid puuliike ning säilikpuid puistu varjus (joonis 1). Selline struktuur pakub rikkalikult elupaiku, näiteks liikidele, kes vajavad, et nende kodumets annaks pidevalt varju või muid liigiomaseid tarbeväärtusi. Püsimetsa majandamine matkib mõne puu suremisega piirduvaid levinumaid looduslikke häiringuid. Samal ajal maandab mitmekesine metsaökosüsteem majanduslikke riske, mis kaasnevad kultuurpuistutega. Minnes meie matka ökosüsteemikeskse külje pealt majanduslikuma poole peale, võib küsida: kas püsimetsandus tasub ennast ära? Püsimetsana majandamine hoiab küll looduslikule järelkasvule tuginedes ning hooldusraieid valikraietega asendades kokku mitmeid kulusid, kuid samas nõuab rohkem hoolt raietöödel allesjääva metsa hoidmiseks. Majandusarvutuste tulemus sõltub sellest, kui pika perioodi lõikes me rehkendame, ning samuti sellest, kas ja kuidas me oskame arvestada looduse hüvesid. Lõpuks saab majandusliku tasuvuse juures määravaks ikkagi meie endi kujundatud arusaam heaolust ja väärtustest – milliseid tegevusi me metsas toetame ning milliseid tooteid ja metsi hindame. Püsimetsas saab kasvatada erinevaid puuliike koos, kasutades ühtlasi ära ühe puuliigi soodsat mõju teisele. Nii võib püsimetsas kasvada tamm, kellel on „pea paljas ja kasukas seljas“, olgu „kasukaks“ siis sarapuud kinnikasvanud puisniidul või meie metsade üks varjutaluvamaid puuliike, kuusk. Sageli arvatakse, et tänu oma varjutaluvusele sobibki vaid kuusk Eesti püsimetsa. Selles arvamuses kajastub tõik, et meie metsamajandus soosib okaspuid, unustades näiteks pärnad ja saared või vahtrad ja tammed. Käesoleva teejuhi üks raskuspunkte langebki nõuannetele, kuidas kasvatada püsimetsas erinevaid puuliike. Keskendumegi retkel ennekõike puidu kasvatamisele. Ka mittepuidulised hüved on kahtlemata olulised paljudele metsaomanikele ja -külalistele, kuid praegusajal vaadeldakse neid enamasti ikka kõrvalkasutusena. Kui metsa üldse majandatakse, siis tüüpiliselt eesmärgiga mingilgi hulgal puitu koguda. Valikraieid tehes saab püsimetsas soosida väljavalitud tulevikupuid, mille kasvamist ja omadusi üritatakse raietega edendada. Kui lageraietega metsa majandav metsaomanik põhjendab noori puid istutades, et rajab palgipuistu järeltulevatele põlvedele raiumiseks, siis püsimetsamajandaja võib tulevastele põlvedele pärandada hästi hoitud erilised jämedatüvelised puud. Ungari püsimetsamajandaja Péter Laczkó on öelnud, et püsimetsandust ei saa ainult koolipingis õppida. Tuleb külastada majandajaid ja nende metsi ning võtta puistustruktuuri ja ökosüsteemi osas eeskuju põlismetsadest. Seda soovitust järgisime ka meie ning kummarda me tänulikult metsamajandajate ees, kes lahkelt oma metsi näitasid ja kogemusi jagasid. Usutlesime 2018. ja 2019. aastal Kagu- ja Lääne-Eesti püsimetsamajandajaid (L. Remm ja M. Kiisel, käsikiri). Kõik ei olnud oma tegevust teadlikult määratlenud püsimetsandusena, kuigi kasutasid vähemalt osaliselt vastavaid võtteid (vt raamatu lõpus olevat tabelit). Külastatud metsade ja nende majandajateni jõudsime valikraieteatiste, metsaühistute, varasemate kontaktide ja juba usutletute soovituste kaudu. Lisatud on üksikuid näiteid Ungarist ja Lätist. Raamatut läbivad püsimetsamajandaja vaadet kajastavad tsitaadid valisime neilt, kes vastavat teemat ühise metsaskäigu jooksul puudutasid. Tsitaadid on esitatud oliivrohelistes kastides kaldkirjas. Raamat algab püsimetsanduse mõiste seletusega Eesti kontekstis ning eri riikide püsimetsandustavade tutvustamisega, et illustreerida lähenemise varieeruvust sõltuvalt loodusoludest ja metsandusajaloost. Eestis ja mujal katsetatud võttestikke tutvustame püsimetsa majandamise peatükis. Arvestades, et püsimetsanduse üks põhimõte on segapuistute kasvatamine, pühendame segametsadele ülevaatliku peatüki ning seejärel vaatleme puuliikide kaupa ja kasvukohatüübiti, kuidas puistuid Eesti tingimustes kujundada. See raamat ei püüa edasi anda kogu teadmistepagasit, mida püsimetsa majandamiseks vaja läheb, vaid eelkõige tuua esile just püsimetsamajanduse eripära võrreldes tavalise, üheealiste puistute lageraiepõhise majandamisega. Jutulõim põimib õpikutarkusi, teadusavastusi ja metsamajandajate kogemusi. Lisaks viidetele on raamatu lõpus ka mõistete seletused. Täname südamest inimesi, kes on aidanud teksti ja jooniseid mõistetavamaks muuta. Käsikirja lugemise ning viljaka arutelu eest võlgneme tänu konsultantidele Anneli Palole, Asko Lõhmusele ja Raul Rosenvaldile. Väiksem ei ole meie tänu käsikirja lugejatele ja nõuandjatele: Mariliis Haljasorg, Maie Kiisel, Eerik Leibak, Jane Remm, Joonas Remm, Kalle Remm ja Algor Streng. Oma kogemusi ja mõtteid jagasid Mattias Luha, Imre Merits ja Hardi Tullus. Võru keele kohta andsid nõu Sulev Iva, Rainer Kuuba ja Triinu Laan

Structural Genomic Variation as Risk Factor for Idiopathic Recurrent Miscarriage

Peer reviewe

First report of highly pathogenic Echinococcus granulosus genotype G1 in dogs in a European urban environment

BACKGROUND: Echinococcus granulosus and E. multilocularis are tapeworm parasites of major medical and veterinary importance, causing cystic and alveolar echinococcosis, respectively. Both diseases are listed among the most severe parasitic diseases in humans, representing 2 of the 17 neglected diseases prioritised by the World Health Organisation. However, little is known about the role of urban animals in transmission of both parasite species. FINDINGS: A sensitive non-invasive genetic method was used to monitor E. granulosus and E. multilocularis infection among dog faecal samples collected from an urban area in Estonia in 2012–13. Out of 181 dog faecal samples analysed, 2.2% tested positive for E. granulosus, determined by sequencing as genotype G1. None of the samples tested positive for E. multilocularis. CONCLUSIONS: We report contamination of an urban environment with highly pathogenic E. granulosus G1 disseminated by dogs, and a potential risk to human health

Haplotype Phasing and Inheritance of Copy Number Variants in Nuclear Families

DNA copy number variants (CNVs) that alter the copy number of a particular DNA segment in the genome play an important role in human phenotypic variability and disease susceptibility. A number of CNVs overlapping with genes have been shown to confer risk to a variety of human diseases thus highlighting the relevance of addressing the variability of CNVs at a higher resolution. So far, it has not been possible to deterministically infer the allelic composition of different haplotypes present within the CNV regions. We have developed a novel computational method, called PiCNV, which enables to resolve the haplotype sequence composition within CNV regions in nuclear families based on SNP genotyping microarray data. The algorithm allows to i) phase normal and CNV-carrying haplotypes in the copy number variable regions, ii) resolve the allelic copies of rearranged DNA sequence within the haplotypes and iii) infer the heritability of identified haplotypes in trios or larger nuclear families. To our knowledge this is the first program available that can deterministically phase null, mono-, di-, tri- and tetraploid genotypes in CNV loci. We applied our method to study the composition and inheritance of haplotypes in CNV regions of 30 HapMap Yoruban trios and 34 Estonian families. For 93.6% of the CNV loci, PiCNV enabled to unambiguously phase normal and CNV-carrying haplotypes and follow their transmission in the corresponding families. Furthermore, allelic composition analysis identified the co-occurrence of alternative allelic copies within 66.7% of haplotypes carrying copy number gains. We also observed less frequent transmission of CNV-carrying haplotypes from parents to children compared to normal haplotypes and identified an emergence of several de novo deletions and duplications in the offspring.Peer reviewe

Natural Variation in Arabidopsis Cvi-0 Accession Reveals an Important Role of MPK12 in Guard Cell CO2 Signaling

Author Summary Human activities have increased the concentrations of CO2 and harmful air pollutants such as ozone in the troposphere. These changes can have detrimental consequences for agricultural productivity. Guard cells, which form stomatal pores on leaves, regulate plant gas exchange. To maintain photosynthesis, stomata open to allow CO2 uptake, but at the same time, open stomata lead to loss of water and allow the entrance of ozone. Elevated atmospheric CO2 levels reduce stomatal apertures, which can improve plant water balance but also increases leaf temperature. Using genetic approaches—in which we exploit natural variation and mutant analysis of thale cress (Arabidopsis thaliana)—we find that MITOGEN-ACTIVATED PROTEIN KINASE 12 (MPK12) and its inhibitory interaction with another kinase, HIGH LEAF TEMPERATURE 1 (HT1) (involved in guard cell CO2 signaling), play a key role in this regulatory process. We have therefore identified a mechanism in which guard cell CO2 signaling regulates how efficiently plants use water and cope with the air pollutant ozone.Peer reviewe

Bilberry (Vaccinium myrtillus) pickers on forest landscape: implications for sustaining a non-timber value

Non-timber-forest-products can offer provisioning services as well as cultural values for a wide range of people. In developed countries gathering of the NTFP has decreased, mostly because of socio-economic changes, but depletion or damaging of key resources can also play a role. Bilberry stands out because of its high anthocyanin content and sensitivity to forest management. We focus on a tradition of bilberry picking in Estonia, where wild berries are gathered by locals both for recreational and commercial purposes and for home use. The most bilberry-rich forests grow on Podzols as well as on paludified and peat soils; silviculture modifies this distribution through clear-cutting and artificial drainage. Based on 53 interviews with regular berry-pickers, we modelled their picking site preferences, established knowledge sources, movement habits, and reactions to forestry. We used availability sampling among recreational and commercial pickers. The absolute values of the results should not be extrapolated, but we think that the trends reflect the real situation in Estonia. A strong majority of respondents agreed to show us their berry picking sites on the condition of confidentiality. The gatherers used clearly delineated picking areas, which constituted a subset of bilberry-rich habitats. The highest preference for dry forests suggested that in addition to the amount of resource, the movement complexity and landscape aesthetics are important factors. Knowing good bilberry places in divergent habitats also stabilises the gathering possibilities regardless of weather-driven yearly variations. Similar conclusions have been deduced from Scandinavian studies. We are not aware of any studies about the behaviour of berry pickers in relation to forest management. In our study, site loss through clear-cutting was experienced as major disturbance (60% of respondents had been forced to find new sites), while bilberry spread in regenerating forests or after drainage was hardly noticed.  The last, together with low preference for drained peatland forest, was surprising, as in general drainage increases the bilberry cover in those forests. Berry-pickers preferred public forests, but had no preference for protected areas. However, in protected areas, site abandonment due to forest management was a very rare case. This appeals for acknowledging the values of protected areas more widely, which could also direct the gatherers to more stable sites. Our study and the pickers' observations distinguished participatory spatial planning of continuous-cover forestry and gap-felling systems in state forests as a priority approach for sustaining traditional bilberry-gathering. Using a representative sample of gatherers to compile a model for spatial planning, could be effective and low-cost approach beside stakeholder involvement, as the knowledge about good bilberry places emerged to be perceived as relatively private information, which value decreases if shared.peerReviewe

Functional Assemblages of Macroinvertebrates in Pools and Ditches in Drained Forest Landscape

Artificially drained commercial forests are hydrologically novel ecosystems, where the array of aquatic habitats consists of ditches and remnant pools. In general the network of ditches has been found to have longer hydroperiod, the knowledge, however, about aquatic invertebrates in this system is scarce. We examined which environmental factors are impacting the biomass and abundance of functional feeding groups. Scrapers and shredders were aggregated to ditches and gatherers to pools. Filterers’ distribution pattern suggested that the function of filtering is carried out by different taxa in pools and ditches. Ditches were rather more suitable for feeding groups that rely on autochthonous resources. Acidity was a major driver of functional community composition, for example, one of the causes for higher scraper frequency in ditches. Predators exhibited greater quantities in extensive macrophyte cover regardless of water body type. Our results suggest that the trophic organization in ditches and pools is different because habitat factors select the feeding groups directly through food resources, but also because of the environmental filter on the other biological traits of the organisms. To support complex ecosystems with several trophic levels also in commercial forests, we suggest to avoid destroying macrophyte rich pools and ditches during silvicultural management.The research was funded by the European Union through the European Regional Development Fund (program 3.2.0802.11-0043) and the Estonian Research Council (grants no 9051 and IUT 34-7).The research was funded by the European Union through the European Regional Development Fund (program 3.2.0802.11-0043) and the Estonian Research Council (grants no 9051 and IUT 34-7)