Elupaiga ja maastiku mõjud päevaliblikakooslustele majandatavates metsades

Väitekirja elektrooniline versioon ei sisalda publikatsiooneElurikkuse vähenemine on üleilmne probleem, mida peamiselt põhjustab looduslike ja poollooduslike elupaikade kadumine. Elupaikade liigilist mitmekesisust mõjutab ka ümbritsev maastik: mida rohkem on elupaigad üksteisest eraldatud, seda enam need liigiliselt vaesuvad. Ehkki kaitsealad on elurikkuse hoidmisel väga tähtsad, ainuüksi neist ei piisa. Järjest enam püütakse leida võimalusi liigirikkuse säilitamiseks ja suurendamiseks ka tugevate inimmõjutustega maastikes. Suurenev nõudlus puidu ja puidutoodete järele on järjest intensiivsemaks muutnud ka metsade majandamise. Metsamajanduse intensiivistumine on paljudele metsaliikidele ohuks, samas leidub ka neid, kellele majandatav metsamaastik elupaigaks sobib. Doktoritöö tulemused viitavad, et üheks selliseks liigirühmaks on metsapäevaliblikad. Paljude liikide röövikud toituvad puudel, põõsastel ja alustaimestiku taimedel, valmikud aga leiavad nektaritaimi raiesmikelt. Niisiis on metsapäevaliblikatele oluline mosaiikne metsamaastik tervikuna – doktoritöös leidsingi, et mida rohkem on ümbritsevas maastikus metsamaad, seda kõrgem on metsaliblikate liigirikkus raiesmikul. Oma töös lähen aga sammu võrra kaugemale ja näitan, et lisaks metsaliikidele pakub majandatav metsamaastik oma mitmesuguste avakooslustega elupaika ka paljudele avamaastikuliikidele. Selgus, et raiesmikud on elupaigaks enamikule regionaalsest päevaliblikafaunast, kellest suurt osa on tavapäraselt seostatud poollooduslike niitudega. Seejuures asustavad niiduliigid ka täielikult metsaga ümbritsetud raiesmikke, millest järeldub, et puistu raiesmikele jõudmisel neile oluliseks takistuseks ei ole. Nii niiduliikide kui metsaliikide koosluseid mõjutavad aga metsa lokaalsed kasvukohatingimused – teatud liigid esinevad sagedamini ja arvukamalt näiteks palumetsades, teised jällegi laane- või salumetsades. Seega on päevaliblikate liigirikkuse seisukohalt oluline elupaikade mitmekesisus, erinevad metsatüübid täiendavad teineteist.Decrease of biodiversity is a global problem mainly caused by loss of natural and semi-natural habitats. Local diversity is also affected by surrounding landscape: isolation of habitats leads to decline of species richness. Despite being important, protected areas alone may be insufficient to maintain biodiversity. The focus is shifting towards sustaining and enhancing species diversity in landscapes of significant human impact. Intensification of forest management due to increasing demand for timber, poses a threat for many forest species. However, some species may find favourable habitat in managed forests. The results of this thesis indicate that forest butterflies are among those. At caterpillar stage, forest butterflies feed on trees, bushes and understorey plants, whereas adults find nectar plants from clear-cuts. Therefore, the whole mosaic of managed forest landscape is important for forest butterflies. Indeed, I found higher species richness of forest butterflies in clear-cuts containing higher proportion of woodland in the surrounding landscape. Furthermore, my thesis shows that managed forest landscape containing various open habitats is also suitable for many open-habitat species. I found that clear-cuts serve as habitats for the majority of regional species pool of butterflies traditionally associated with semi-natural grasslands. Moreover, grassland species reach even to clear-cuts completely surrounded with forest, which implies that forest is not a significant barrier for colonisation. Assemblages of grassland species and forest species are both affected by local environmental conditions of forest: different forest types provide habitat for distinct butterfly assemblages. The diversity of forest types is therefore important for maintaining species richness of butterflies, as different forest habitat types complement each other.https://www.ester.ee/record=b524411

The effect of natural disturbances on forest biodiversity: an ecological synthesis

Disturbances alter biodiversity via their specific characteristics, including severity and extent in the landscape, which act at different temporal and spatial scales. Biodiversity response to disturbance also depends on the community characteristics and habitat requirements of species. Untangling the mechanistic interplay of these factors has guided disturbance ecology for decades, generating mixed scientific evidence of biodiversity responses to disturbance. Understanding the impact of natural disturbances on biodiversity is increasingly important due to human-induced changes in natural disturbance regimes. In many areas, major natural forest disturbances, such as wildfires, windstorms, and insect outbreaks, are becoming more frequent, intense, severe, and widespread due to climate change and land-use change. Conversely, the suppression of natural disturbances threatens disturbance-dependent biota. Using a meta-analytic approach, we analysed a global data set (with most sampling concentrated in temperate and boreal secondary forests) of species assemblages of 26 taxonomic groups, including plants, animals, and fungi collected from forests affected by wildfires, windstorms, and insect outbreaks. The overall effect of natural disturbances on α-diversity did not differ significantly from zero, but some taxonomic groups responded positively to disturbance, while others tended to respond negatively. Disturbance was beneficial for taxonomic groups preferring conditions associated with open canopies (e.g. hymenopterans and hoverflies), whereas ground-dwelling groups and/or groups typically associated with shady conditions (e.g. epigeic lichens and mycorrhizal fungi) were more likely to be negatively impacted by disturbance. Across all taxonomic groups, the highest α-diversity in disturbed forest patches occurred under moderate disturbance severity, i.e. with approximately 55% of trees killed by disturbance. We further extended our meta-analysis by applying a unified diversity concept based on Hill numbers to estimate α-diversity changes in different taxonomic groups across a gradient of disturbance severity measured at the stand scale and incorporating other disturbance features. We found that disturbance severity negatively affected diversity for Hill number q = 0 but not for q = 1 and q = 2, indicating that diversity–disturbance relationships are shaped by species relative abundances. Our synthesis of α-diversity was extended by a synthesis of disturbance-induced change in species assemblages, and revealed that disturbance changes the β-diversity of multiple taxonomic groups, including some groups that were not affected at the α-diversity level (birds and woody plants). Finally, we used mixed rarefaction/extrapolation to estimate biodiversity change as a function of the proportion of forests that were disturbed, i.e. the disturbance extent measured at the landscape scale. The comparison of intact and naturally disturbed forests revealed that both types of forests provide habitat for unique species assemblages, whereas species diversity in the mixture of disturbed and undisturbed forests peaked at intermediate values of disturbance extent in the simulated landscape. Hence, the relationship between α-diversity and disturbance severity in disturbed forest stands was strikingly similar to the relationship between species richness and disturbance extent in a landscape consisting of both disturbed and undisturbed forest habitats. This result suggests that both moderate disturbance severity and moderate disturbance extent support the highest levels of biodiversity in contemporary forest landscapes.British Ecological Society LRB20/1002Junta de AndaluciaEuropean Commission B-FQM-366-UGR20Centro ANID Basal FB210015Direccion de Investigacion Universidad de La Frontera DIUFRO DI20-0066Federal Ministry of Education & Research (BMBF)Max Planck SocietyINCT Madeiras da AmazoniaFederal Ministry of Education & Research (BMBF) 01LB1001A 01LK1602ABrazilian Ministry of Science, Technology and Innovation (MCTI/FINEP) 01.11.01248.00Max Planck SocietyRussian Science Foundation (RSF) 21-14-00227Ministry of Education, Youth & Sports - Czech Republic Czech Republic Government LTC 20058Czech Academy of Sciences RVO67985939UK Research & Innovation (UKRI)Natural Environment Research Council (NERC) GR3/11743Greek project POL-AEGIS, Program THALES MIS 376737Projekt DEAL TH 2218/5-

Effects of different types of low-intensity management on plant-pollinator interactions in Estonian grasslands

In the face of global pollinator decline, extensively managed grasslands play an important role in supporting stable pollinator communities. However, different types of extensive management may promote particular plant species and thus particular functional traits. As the functional traits of flowering plant species (e.g., flower size and shape) in a habitat help determine the identity and frequency of pollinator visitors, they can also influence the structures of plant-pollinator interaction networks (i.e., pollination networks). The aim of this study was to examine how the type of low-intensity traditional management influences plant and pollinator composition, the structure of plant-pollinator interactions, and their mediation by floral and insect functional traits. Specifically, we compared mown wooded meadows to grazed alvar pastures in western Estonia. We found that both management types fostered equal diversity of plants and pollinators, and overlapping, though still distinct, plant and pollinator compositions. Wooded meadow pollination networks had significantly higher connectance and specialization, while alvar pasture networks achieved higher interaction diversity at a standardized sampling of interactions. Pollinators with small body sizes and short proboscis lengths were more specialized in their preference for particular plant species and the specialization of individual pollinators was higher in alvar pastures than in wooded meadows. All in all, the two management types promoted diverse plant and pollinator communities, which enabled the development of equally even and nested pollination networks. The same generalist plant and pollinator species were important for the pollination networks of both wooded meadows and alvar pastures; however, they were complemented by management-specific species, which accounted for differences in network structure. Therefore, the implementation of both management types in the same landscape helps to maintain high species and interaction diversity

Subtle structures with not-so-subtle functions: A dataset of arthropod constructs and their host plants

The construction of shelters on plants by arthropods might influence other organisms via changes in colonization, community richness, species composition and functionality. Arthropods, including beetles, caterpillars, sawflies, spiders, and wasps often interact with host plants via the construction of shelters, building a variety of structures such as leaf ties, tents, rolls, and bags; leaf and stem galls, and hollowed out stems. Such constructs might have both an adaptive value in terms of protection (i.e., serve as shelters) but may also exert a strong influence on terrestrial community diversity in the engineered and neighboring hosts via colonization by secondary occupants. While different traits of the host plant (e.g., physical, chemical and architectural features) may affect the potential for ecosystem engineering by insects, such effects have been, to a certain degree, overlooked. Further analyses of how plant traits affect the occurrence of shelters may thus enrich our understanding of the organizing principles of plant-based communities. This dataset includes more than a thousand unique records of ecosystem engineering by arthropods, in the form of structures built on plants. All records have been published in the literature, and span both natural structures (90.6% of the records) and structures artificially created byresearchers (9% of the records). The data were gathered between 1932 and 2021, across more than 50 countries and several ecosystems, ranging from polar to tropical zones. Besides data on host plants and engineers, we aggregated data on the type of constructs and the identity of inquilines using these structures. This dataset highlights the importance of these subtle structures for the organization of terrestrial arthropod communities, enabling hypotheses testing in ecological studiesaddressing ecosystem engineering and facilitation mediated by constructs.Fil: Pereira, Cássio Cardoso. Universidade Federal de Minas Gerais; BrasilFil: Novais, Samuel. Instituto de Ecología; MéxicoFil: Barbosa, Milton. Universidade Federal de Minas Gerais; BrasilFil: Negreiros, Daniel. Universidade Federal de Minas Gerais; BrasilFil: Gonçalves Souza, Thiago. Universidade Federal de Pernambuco; BrasilFil: Roslin, Tomas. Swedish University Of Agricultural Sciences; SueciaFil: Marquis, Robert. University of Missouri; Estados UnidosFil: Marino, Nicholas. Universidade Federal do Rio de Janeiro; BrasilFil: Novotny, Vojtech. Biology Centre of the Academy of Sciences of the Czech Republic; República ChecaFil: Orivel, Jerome. Universite de Guyane; GuyanaFil: Sui, Shen. New Guinea Binatang Research Center; GuineaFil: Aires, Gustavo. Universidade Federal de Pernambuco; BrasilFil: Antoniazzi, Reuber. University of Texas at Austin; Estados UnidosFil: Dáttilo, Wesley. Instituto de Ecología; MéxicoFil: Breviglieri, Crasso. Universidade Estadual de Campinas; BrasilFil: Busse, Annika. Bavarian Forest National Park; AlemaniaFil: Gibb, Heloise. La Trobe University. Department Of Ecology, Environment And Evolution; AustraliaFil: Izzo, Thiago. Universidade Federal do Mato Grosso do Sul; BrasilFil: Kadlec, Tomas. Czech University Of Life Sciences Prague; República ChecaFil: Kemp, Victoria. Queen Mary University of London; Reino UnidoFil: Kersch Becker, Monica. University of Alabama at Birmingahm; Estados UnidosFil: Knapp, Michal. Czech University Of Life Sciences Prague; República ChecaFil: Kratina, Pavel. Queen Mary University of London; Reino UnidoFil: Luke, Rebecca. Royal Holloway University of London; Reino UnidoFil: Majnari, Stefan. University Of Zagreb, Faculty Of Science; CroaciaFil: Maritz, Robin. University of the Western Cape; SudáfricaFil: Martins, Paulo Mateus. Universidade Federal de Pernambuco; BrasilFil: Mendesil, Esayas. Jimma University; EtiopíaFil: Michalko, Jaroslav. Slovak Academy of Sciences; EslovaquiaFil: Mrazova, Anna. Biology Centre of the Academy of Sciences of the Czech Republic; República ChecaFil: Peri, Mirela Serti. University Of Zagreb. Faculty Of Science; CroaciaFil: Petermann, Jana. University Of Salzburg. Department Of Biosciences; AustriaFil: Ribeiro, Sérvio. Universidade Federal de Ouro Preto; BrasilFil: Sam, Katerina. University of Missouri; Estados UnidosFil: Trzcinski, M. Kurtis. University of British Columbia; CanadáFil: Vieira, Camila. Universidade Federal de Uberlândia; BrasilFil: Westwood, Natalie. University of British Columbia; CanadáFil: Bernaschini, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Carvajal, Valentina. Universidad de Caldas; ColombiaFil: González, Ezequiel. Czech University of Life Sciences Prague; República ChecaFil: Jausoro, Mariana. Universidad Nacional de Chilecito. Departamento de Ciencias Basicas y Tecnologicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Kaensin, Stanis. New Guinea Binatang Research Center; GuineaFil: Ospina, Fabiola. Universidad de Caldas; ColombiaFil: Pérez, Jacob Cristóbal. Universidad Autónoma del Estado de México; MéxicoFil: Quesada, Mauricio. Universidad Autónoma del Estado de México; MéxicoFil: Rogy, Pierre. University of British Columbia; CanadáFil: Srivastava, Diane S.. University of British Columbia; CanadáFil: Szpryngiel, Scarlett. The Swedish Museum of Natural History; SueciaFil: Tack, Ayco J. M.. Stockholms Universitet; SueciaFil: Teder, Tiit. University of Tartu; EstoniaFil: Videla, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Viljur, Mari Liis. University of Tartu; EstoniaFil: Koricheva, Julia. Royal Holloway University of London; Reino UnidoFil: Fernandes, Geraldo Wilson Afonso. Universidade Federal de Minas Gerais; BrasilFil: Romero, Gustavo Q.. Universidade Estadual de Campinas; BrasilFil: Cornelissen, Tatiana. Universidade Federal de Minas Gerais. Instituto de Ciências Biológicas; Brasi

The effect of natural disturbances on forest biodiversity: an ecological synthesis

Disturbances alter biodiversity via their specific characteristics, including severity and extent in the landscape, which act at different temporal and spatial scales. Biodiversity response to disturbance also depends on the community characteristics and habitat requirements of species. Untangling the mechanistic interplay of these factors has guided disturbance ecology for decades, generating mixed scientific evidence of biodiversity responses to disturbance. Understanding the impact of natural disturbances on biodiversity is increasingly important due to human-induced changes in natural disturbance regimes. In many areas, major natural forest disturbances, such as wildfires, windstorms, and insect outbreaks, are becoming more frequent, intense, severe, and widespread due to climate change and land-use change. Conversely, the suppression of natural disturbances threatens disturbance-dependent biota. Using a meta-analytic approach, we analysed a global data set (with most sampling concentrated in temperate and boreal secondary forests) of species assemblages of 26 taxonomic groups, including plants, animals, and fungi collected from forests affected by wildfires, windstorms, and insect outbreaks. The overall effect of natural disturbances on α-diversity did not differ significantly from zero, but some taxonomic groups responded positively to disturbance, while others tended to respond negatively. Disturbance was beneficial for taxonomic groups preferring conditions associated with open canopies (e.g. hymenopterans and hoverflies), whereas ground-dwelling groups and/or groups typically associated with shady conditions (e.g. epigeic lichens and mycorrhizal fungi) were more likely to be negatively impacted by disturbance. Across all taxonomic groups, the highest α-diversity in disturbed forest patches occurred under moderate disturbance severity, i.e. with approximately 55% of trees killed by disturbance. We further extended our meta-analysis by applying a unified diversity concept based on Hill numbers to estimate α-diversity changes in different taxonomic groups across a gradient of disturbance severity measured at the stand scale and incorporating other disturbance features. We found that disturbance severity negatively affected diversity for Hill number q = 0 but not for q = 1 and q = 2, indicating that diversity-disturbance relationships are shaped by species relative abundances. Our synthesis of α-diversity was extended by a synthesis of disturbance-induced change in species assemblages, and revealed that disturbance changes the β-diversity of multiple taxonomic groups, including some groups that were not affected at the α-diversity level (birds and woody plants). Finally, we used mixed rarefaction/extrapolation to estimate biodiversity change as a function of the proportion of forests that were disturbed, i.e. the disturbance extent measured at the landscape scale. The comparison of intact and naturally disturbed forests revealed that both types of forests provide habitat for unique species assemblages, whereas species diversity in the mixture of disturbed and undisturbed forests peaked at intermediate values of disturbance extent in the simulated landscape. Hence, the relationship between α-diversity and disturbance severity in disturbed forest stands was strikingly similar to the relationship between species richness and disturbance extent in a landscape consisting of both disturbed and undisturbed forest habitats. This result suggests that both moderate disturbance severity and moderate disturbance extent support the highest levels of biodiversity in contemporary forest landscapes