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Prediçao de distribuíção de espécies arbustivo-arbóreas no sul do Brasil / Prediction of distribution of shrub and trees species in southern BrazilVerdi, Marcio January 2013 (has links)
Em vista das mudanças ambientais em nível global, disponibilizar informações ecológicas e buscar uma melhor compreensão dos fatores e processos que moldam a distribuição de espécies, é uma iniciativa importante para o planejamento de ações de conservação. Neste contexto, a importância e carência de informações sobre a distribuição geográficas das espécies nos motivaram a predizer a distribuição potencial de arbustos e árvores das famílias Lauraceae e Myrtaceae na Floresta Atlântica, no sul do Brasil. Modelos lineares generalizados (GLM) foram usados para ajustar modelos preditivos com os registros de ocorrência de 88 espécies em função de variáveis ambientais. As variáveis preditoras foram selecionadas com base no menor critério de informação de Akaike corrigido. Nós avaliamos o desempenho dos modelos usando o método de validação cruzada (10-fold) para calcular a habilidade estatística verdadeira (TSS) e a área sob a curva característica do operador receptor (AUC). Nós usamos GLM para testar a influência da área de ocorrência estimada, do número de registros das espécies e da complexidade dos modelos sobre a TSS e a AUC. Nossos resultados mostraram que as variáveis climáticas governam amplamente a distribuição de espécies, mas as variáveis que captam as variações ambientais locais são relativamente importantes na área de estudo. A TSS foi significativamente influenciada pelo número de registros e complexidade dos modelos, enquanto a AUC sofreu com o efeito de todos os três fatores avaliados. A interação entre estes fatores é uma questão importante e a ser considerada em novas avaliações sobre ambas medidas e com diferentes técnicas de modelagem. Nossos resultados também mostraram que as distribuições de algumas espécies foram superestimadas e outras corresponderam bem com a ocorrência por nós conhecida. Efetivamente nossos resultados têm fundamentos para embasar novos levantamentos de campo, a avaliação de áreas prioritárias e planos de conservação, além de inferências dos efeitos de mudanças ambientais sobre as espécies da Mata Atlântica. / In view of environmental change on a global level, providing ecological information and getting a better understanding of the factors and processes that shape species distribution is an important initiative for planning conservation actions. In this context, the importance and lack of information about the geographical distribution of species motivated us to predict the potential species distribution of shrubs and trees of the family Lauraceae and Myrtaceae, in the Atlantic Forest in southern Brazil. Generalized linear models (GLM) were used to fit predictive models with records of occurrence of 88 species according to environmental variables. Predictor variables were selected based on the lowest corrected Akaike information criterion. We evaluate the performance of the models using the method of cross-validation (10-fold) to calculate the true skill statistic (TSS) and area under the receiver operator characteristic curve (AUC). We used GLM to test the influence of the area of occurrence estimated, the number of records of the species and the complexity of the models on the TSS and AUC. Our results show that climatic variables largely govern the distribution of species, but the variables that capture the local environmental variations are relatively important in the study area. The TSS was significantly influenced by the number of records and complexity of models while the AUC suffered from the effect of all three evaluated factors. The interaction between these factors is an important issue and be considered for new reviews on both measures and with different modeling techniques. Our results also showed that the distributions of some species were overestimated and other corresponded well with the occurrence known to us. Indeed our results have foundations to support new field surveys, assessment of priority areas and conservation plans, and inferences of the effects of environmental change on species of the Atlantic Forest.
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Habitats adequados e aspectos ecológicos do tubarão-baleia (Rhincodon, typus Smith 1828) no Oceano Atlântico Sudoeste e EquatorialROCHA, Bruno César Luz 01 December 2016 (has links)
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Previous issue date: 2016-12-01 / CNPQ / Compreender detalhadamente a história de vida do tubarão-baleia é fundamental para
assegurar a sua conservação. No entanto, apesar da espécie possuir distribuição circumglobal
e ser relativamente bem estudada entre os elasmobrânquios, ainda existe uma grande escassez
de informações relacionadas a muitos dos seus aspectos ecológicos e biológicos em todo o
mundo, principalmente no que diz respeito aos seus movimentos migratórios e ciclo
reprodutivo. No Oceano Atlântico, particularmente, a espécie vem sendo investigada
majoritariamente no Golfo do México/ Mar do Caribe, permanecendo uma grande lacuna para
o restante dessa bacia oceânica. O presente estudo representa a primeira iniciativa de
investigação da distribuição espacial do tubarão-baleia em escala oceânica no sudoeste do
Atlântico baseada em registros de ocorrências na costa do Brasil, além de ter sido o primeiro
trabalho também sobre o rastreamento de tubarões-baleia na região equatorial. Com o objetivo
de complementar o conhecimento acerca da distribuição geográfica e movimentação do
tubarão-baleia nas regiões sudoeste e equatorial do oceano Atlântico, foram empregadas
técnicas modernas de modelagem ecológica e rastreamento via satélite, além da utilização do
método tradicional de censo visual para identificação de aspectos populacionais no
Arquipélago de São Pedro e São Paulo (ASPSP). Primeiramente, foram realizadas predições
referentes à distribuição espacial de habitats adequados para alimentação e inferências sobre a
influência de variáveis ambientais específicas para ocorrência do tubarão-baleia na costa do
Brasil/ sudoeste do oceano Atlântico. Em seguida, a sazonalidade, a abundância relativa e a
estrutura populacional dos tubarões-baleia que visitam o ASPSP foram investigadas,
incluindo inferências acerca da importância de ecossistemas insulares oceânicos para a
parcela madura da espécie. Por fim, na terceira parte da Tese, os deslocamentos horizontais e
verticais de tubarões-baleia marcados com transmissores via satélite no ASPSP foram
descritos e o comportamento de mergulho avaliado com relação a fatores biofísicos e
ambientais específicos. Os resultados obtidos no presente estudo são relevantes não somente
para a conservação do tubarão-baleia, mas para o ecossistema marinho na costa do Brasil, de
uma forma geral, posto que o mapeamento de habitats ideais para alimentação da espécie
também serve para identificar áreas ecologicamente importantes para outras espécies.
Ademais, a identificação do ASPSP como uma área importante para a parcela adulta dos
tubarões-baleia ressalta sua importância ecológica no ciclo de vida da espécie, destacando a
necessidade de se envidar maiores esforços para a conservação do local. / Understanding the life history of the whale shark is fundamental to assure its conservation.
However, in spite of the circumglobal distribution of the species and the fact that it is
relatively well studied among elasmobranchs, there is still a serious lack of information
concerning its biology in the entire world, mainly regarding its migratory movements and
reproductive cycle. In the Atlantic Ocean, particularly, the whale sharks have been
predominantly studied in the Gulf of Mexico/Caribbean Sea, with a big gap still remaining for
the rest of this ocean basin. Aiming to help to fill this gap on geographical distribution and
movement patterns of whale sharks in the Equatorial and Southwest Atlantic regions, modern
techniques of ecological modelling and satellite tracking were used, in addition to the use of
scientific traditional method of visual census to describe the population aspects of the species
in the archipelago of São Pedro and São Paulo (ASPSP). Firstly, geographical predictions of
suitable habitats for whale shark feeding and inferences of the influence of specific
environmental variables on the occurrence distribution in the Brazilian coast/southwestern
Atlantic Ocean were conducted to describe the potential spatial distribution of the species.
Then, the seasonality of occurrence, relative abundance and population structure of the whale
sharks visiting the ASPSP were investigated, including a discussion regarding the importance
of the insular oceanic ecosystems to the mature portion of the species. Finally, in the third part
of the thesis, the horizontal and vertical displacements of whale sharks satellite tagged off
ASPSP were described and the diving behavior assessed in relation to specific biophysical
and environmental factors. The present study represents the first oceanic-scale spatial
distribution investigation effort in the southwest Atlantic on whale shark presence records
from the Brazilian coast, besides of being the first study using satellite tracking on the species
in the equatorial Atlantic as well. The results presented here are of great relevance not only
for the whale shark conservation but also for the Brazilian marine ecosystem, as the mapping
of suitable feeding habitats could contribute to the identification of areas of ecological
importance to other marine species. Moreover, the identification of the ASPSP as an
important area for the mature part of whale shark populations highlights its ecological
relevance on the species life cycle, emphasizing the need of increasing the conservation
efforts in this habitat.
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Considerações sobre a biodiversidade de abelhas brasileiras: vícios de coleta, distribuições potenciais e fragmentação / Considerations on the biodiversity of brazilian bees: collection defects, potential distributions and fragmentationSilva, Daniel de Paiva 28 February 2014 (has links)
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Previous issue date: 2014-02-28 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The world we live in faces fast and intense environmental changes, deeply related to human activities, which directly or indirectly are related to the current biodiversity crisis. Thus, the existence of quality biological, ecological, and distributional data is of utmost importance for the support of active conservation practices. Nonetheless, both Linnean (lack of taxonomical data) and Wallacean (lack of distributional data) shortfalls are important setbacks hindering the effectiveness of conservationist decisions. The data harbored in museums and overall collections is excellent to support conservational measures. Nonetheless, usually this data is biased and needs to be adequately filtered before being used. Insect and arthropod species are under sampled, what impedes them to be properly considered under Conservation Biogeography frameworks. In such scenario, even insect groups with relatively known biology and ecology are neglected in practical conservation actions. Despite that, with the advent of new computational tools allied with good theories and good distributional data of insect species, it is possible to contemplate those biological groups in concrete and efficient conservation actions. Therefore, in the first part of this thesis, considering bees from the Megachile genus (Chapter 1) and from the Meliponini tribe (Chapter 2), we evaluated potential biases affecting those data, but also evaluate potential areas for new field surveys. The Wallacean shortfalls are commonly used to justify the implementation of new field surveys. Therefore, in the second part of this thesis, we used the new occurrences of the bee species [Aglae caerulea (Apidae: Eulgossini) – Chapter 3; and the exotic species, Lithurgus huberi (Apidae: Lithurgini) – Chapter 4] allied with distribution modelling to predict these species potential distributions and indicate areas for future new samplings. On the third and last part of the thesis, we considered a regional spatial scale and habitat loss and fragmentation questions to address their effects on the bee biodiversity from the Cerrado biome found within the Goiás state. In Chapter 5, we evaluated the effects of anthropic areas amount and their isolation on two orchid-bee species from the Cerrado (Eulaema nigrita and Eufriesea auriceps), which apparently are not affected by the increase of anthropic areas in this biome. Later, in the last chapter (Chapter 6), we evaluated the response of all bee community we sampled in Cerrado areas within state of Goiás, as well as the sub groups of eusocial and solitary species, to the landscape structure of our sampling areas, considering different local spatial scales. / O mundo vive rápidas e intensas mudanças ambientais intimamente relacionadas às atividades humanas e que, direta ou indiretamente, estão relacionadas à atual crise de biodiversidade. Assim, a existência de dados biológicos, ecológicos e distribucionais de qualidade é de extrema importância dar suporte a tomada de ações práticas de conservação. Entretanto, os déficits Linneanos (falta de dados taxonômicos) e Wallaceanos (falta de dados distribucionais) são importantes problemas que impedem a efetiva tomada de decisões conservacionistas. Neste contexto, dados provenientes de museus e coleções, após cuidadosa filtragem, são excelentes para apoiarem tais ações. Em geral, esta informação é enviesada e necessita de cuidado adequado antes de ser utilizada. Espécies de artrópodes e insetos são sub amostrados, impedindo sua utilização em propostas práticas de conservação utilizadas na Biogeografia da Conservação. Neste cenário, mesmo grupos cuja ecologia e biologia são bem conhecidas, acabam não sendo utilizados. Apesar disso, o advento de novas ferramentas computacionais aliados a boas teorias e bons dados de distribuição das espécies de insetos, é possível a contemplação do uso de vários grupos entomológicos em ações concretas de conservação. Assim, na primeira parte da presente tese, considerando abelhas do gênero Megachile (Capítulo 1) e da tribo Meliponini (Capítulo 2), nós analisamos os eventuais vícios de amostragem existentes nos dados de ocorrência das espécies destes gêneros, descrevendo o estado atual do conhecimento da distribuição destas abelhas e áreas para potenciais amostragens futuras. Os déficits Wallaceanos são frequentemente utilizados como justificativa para a realização de novos inventários biológicos. Deste modo, na segunda parte desta tese, nós utilizamos novas ocorrências de duas espécies de abelhas (Agale caerulea (Apidae: Euglossini) – Capítulo 3; e a espécie invasora Lithurgus huberi (Apidae: Lithurgini) – Capítulo 4) com abordagens de modelagens de distribuição potencial para predizer suas distribuições e indicar locais ideias para novas coletas. Na terceira e última parte desta tese, considerando-se uma escala espacial mais regional, nós consideramos questões de perda de habitats e fragmentação sobre a biodiversidade de abelhas do Cerrado goiano. No capítulo 5, nós avaliamos os efeitos da quantidade de habitat e isolamento sobre duas espécies de abelhas das orquídeas do Cerrado (Elaema nigrita e Eufriesea auriceps), que, aparentemente não são afetadas pelo aumento de áreas antrópicas no bioma. Por fim, no último capítulo (Capítulo 6), nós avaliamos a resposta de toda a comunidade de abelhas coletadas em áreas de Cerrado de Goiás, bem como a resposta das espécies de grupos de abelhas solitárias e eusociais, à estrutura da paisagem dos nossos pontos de coletas, em diferentes escalas espaciais locais.
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A Tale of Two Species: Black-tailed and White-tailed Prairie Dog Biogeography from the Last Interglacial to 2070Bledsoe, April Dawn 01 May 2020 (has links)
Ecological niche models (ENMs) were created for White-tailed and Black-tailed prairie dogs and projected into the Last Interglacial (LI), the Last Glacial Maximum (LGM), and mid-Holocene (mid-H) to discern possible past suitable habitat for both species. Additionally, ENMs were projected into the future year 2070 representative concentration pathways (RCPs) 2.6 and 8.5 to discern how climate change may affect future habitat suitability. Kernel density estimations, minimum convex polygons, and median distribution centers of White-tailed and Black-tailed occurrence records were examined between time-periods to discern the effects of anthropogenic westward expansion on both species’ distributions. Current ENMs were constructed from commonly used bioclimatic variables and non-traditional variables (including EPA level III Ecoregions) for White-tailed and Black-tailed prairie dogs for variable comparison performance in ENMs. Results indicate that both species respond to climate change and each occupy distinct ecological niches. Biogeographical changes coincident with westward expansion remain unknown.
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Modeling distributions of Cantharellus formosus using natural history and citizen science dataArmstrong, Zoey Nicole 21 April 2021 (has links)
No description available.
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Procena efektivnosti zaštićenih područja i IBA mreže za odabrane vrsta ptica u Srbiji / Estimating the effectiveness of protected areas and IBA network in the conservation of selected bird species in SerbiaRadišić Dimitrije 23 September 2019 (has links)
<p>U radu je analizirana efektivnost zaštićenih područja Srbije u sadašnjosti i budućnosti na osnovu zastupljenosti povoljnih staništa i centara diverziteta 116 običnih vrsta ptica odabranih na osnovu 11 kriterijuma. Zasebno su evaluirana zaštićena prirodna dobara, međunarodno značajna područja za ptice (IBA) i mreža nastala preklapanjem dva tipa zaštićenih područja. Povoljna staništa istraživanih vrsta utvrđena su modelovanjem distribucije vrsta uz pomoć MaxEnt pristupa, a modeli distribucije projektovani su na četiri različita scenarija klimatskih promena u budućnosti (2050. godina). IBA mreža pokazala se kao značajno<br />efektivnija za zaštitu staništa istraživanih vrsta i centara njihvog diverziteta u odnosu na mrežu zaštićenih prirodnih dobara, a slična situacija predviđena je i u budućnosti. Oba tipa zaštićenih područja pokrivala su u proseku srazmerno mali procenat povoljnih staništa istraživanih vrsta (zaštićena prirodna dobra –<br />10,4%; IBA – 21,9%) i dovela su do ostvarivanja konzervacionih ciljeva malog broja vrsta (zaštićena prirodna dobra – 11; IBA - 37), dok su centri diverziteta istraživanih vrstasrazmerno slabo zastupljeni unutar obe mreže (zaštićena prirodna dobra – 9,8%; IBA – 25,4%). Zaštićena područja nisu pokazale<br />značajno veću efektivnost za konzervaciono prioritetnt vrste i njihov diverzitet. Zaštićena prirodna dobra i IBA mreža u Srbiji značajno bolje pokrivaju staništa i centre diverziteta šumskih vrsta i vrsta kamenjara, klisura i litica, dok su povoljna staništa i centri diverziteta gnezdarica poljoprivrednih staništa, naselja i vodenih staništa izrazito slabo zastupljena. Staništa gnezdarica nizijskih poljoprivrednih<br />staništa naročito su slabo zastupljena unutar zaštićenih prirodnih dobara i IBA mreže, koja za ovu grupu nisu dovela do postizanja konzervacionih ciljeva. Razlike u efektivnosti zaštićenih područja za gnezdarice različitih tipova staništa u budućnosti će se generalno povećavati, usled predviđenog smanjivanja<br />areala većine šumskih vrsta koje će se povlačiti u zaštitom bolje pokrivene planinske predele i širenja areala većine gnezdarica poljoprivrednih i vodenih staništa na nezaštićena nizijska područja. Za deo vrsta među kojima dominiraju<br />gnezdarice brdsko-planinskih šumskih i drugih prirodnih staništa glavna strategija zaštite podrazumeva precizno proširenje granica sadašnjih zaštićenih područja uz upravljanje orentisano ka očuvanju prirodnih staništa i smanjenju iskorišćavanja resursa. Sa druge strane, za većinu gnezdarica poljoprivrednih i<br />travnih staništa, naročito u nizijskim predelima, efektivna strategija bila bi definisanje potpuno novih i prostranih zaštićenih područja orijentisanih ka održavanju povoljnog režima upravljanja i korišćenja prostora. Rad ukazuje<br />na velike mogućnosti korišćenja nesistematično prikupljenih podataka profesionalnih i amaterskih ornitologa uz primenu tehnika modelovanja distribucije vrsta, ali naglašava potrebu za pokretanjem širokih programa<br />sistematskog popisa, kartiranja i monitoringa običnih vrsta ptica.</p> / <p>The study analyzes the effectiveness of protected areas in Serbia presently as well as in the future, based on the representation of suitable habitats and centers of diversity for 116 common species of birds, selected on the basis of 11 criteria. Nationally protected areas, Important Bird and Biodiversity areas (IBAs) and networks formed by overlapping these two types of protected areas have been evaluated separately. Suitable habitats of the species in the study were determined by species distribution modeling using the MaxEnt approach, and the distribution models were projected to four different climate change scenarios in future (year 2050). The IBA network proved to be significantly more effective for the protection of habitats of studied species and centers of their diversity, compared to the network of nationally protected areas, and a similar situation is projected for the future. Both types of protected areas on average covered a relatively small percentage of suitable habitats for most species (10.4% in nationaly protected areas, 21.9% in IBA) and meet conservation goals only for a small number of species (11 for nationaly protected areas, 37 for IBA). Diversity centers for species in the study are relatively poorlyrepresented within all three networks (9.8% for nationaly protected areas and 25.4% for IBA). Protected areas did not show significantly higher effectiveness for the conservation of priority species and their diversity. Nationaly protected areas and the IBA network in Serbia have a significantly better coverage of habitats and centers of diversity for forest species and species of rocky habitats, cliffs and gorges, while suitable habitats and centers of diversity for breeding birds of farmlands, settlements and aquatic habitats are very poorly represented. Habitats of breeding birds of lowland armlands are particularly poorly represented within protected natural assets and the IBA network, and this measure does not meet the conservation goals for this group of birds. Differences in the effectiveness of protected areas for breeding birds of various habitat types will generally increase in the future, due to the anticipated range decrease for most forest species that will withdraw to the better conserved mountainous areas, whereas range of the majority o f breeding birds of farmland and aquatic habitats will be expanded to unprotected lowland areas. For some of the species, mostly birds of hill and mountain forests and other natural habitats, the main conservation strategy implies precise boundaries extension of the current protected areas with management directed towards preserving natural habitats and reducing the utilization of resources. On the other hand, for most of the farmland and grassland species, especially in the lowlands, an effective strategy would be to define completely new and spacious protected areas oriented towards maintaining a favorable regime for management and landuse. The study demonstrates that there are great possibilities of using nonsystematically collected data from professiona l and amateur ornithologists, for application in species distribution modeling, but also emphasizes the need to launch extensive programs for systematic inventory, mapping and monitoring of common bird species.</p>
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A cooperative effort to track Humboldt squid invasions in OregonChesney, Tanya A. 04 September 2012 (has links)
Interannual variability of Humboldt squid (Dosidicus gigas) occurrence in the
northern California Current System is largely unknown. In Oregon, the distribution of
this versatile predator and what is influencing their range expansion from Mexico is
poorly understood due to the recent nature of their "invasion" and a lack of
monitoring. Humboldt squid are large predators that have the potential to affect
ecosystem structure and fisheries because of their high-energy demands and ability to
exploit a variety of oceanographic conditions and prey sources. Developing baseline
distribution information is a critical first step to assess their potential ecological,
social, and economic impacts, and to develop models to predict future range
expansion.
This study has two main objectives: (1) to document where and when
Humboldt squid have been present in Oregon through cooperative fisheries research,
and (2) to correlate the sightings with oceanographic conditions using a geographic
information system (GIS) and species distribution modeling (SDM). I conducted 54
interviews with local fishermen and aggregated their squid sightings with available
fishery-independent survey and fishery-dependent observer data from the National
Marine Fisheries Service. I compiled a total of 339 Humboldt squid sightings,
reported for the years 2002-2011 from the Oregon coast to 131�� west longitude.
Correlation analyses were performed for Humboldt squid sightings and sea surface
temperature (SST), chlorophyll a content (chla), sea surface height anomalies (SSH),
dissolved oxygen at 30 m depth (30 m DO), and sea surface salinity (SSS) using a
GIS, nonparametric multiplicative regression (NPMR) habitat modeling, and
maximum entropy modeling (Maxent). Results indicate that oceanographic conditions
have the potential to influence Humboldt squid occurrence, and in Oregon, sightings
vary temporally and spatially. Combining the sightings from fishermen and scientific
surveys greatly enhanced the spatial extent of the data. Humboldt squid were most
frequently observed between 124.4��W and 125��W in proximity to the shelf-break at
the 200 m isobath, with peak sightings (116) recorded in 2009 and the fewest (6)
reported in 2003 and 2011. The highest occurrence of Humboldt squid were observed
at a SST of 10.5-13.0��C, 0.26-3.0 mg m����� chla content, -4.0-1.0 m SSH anomalies,
32.2-32.8 psu SSS, and at 3-4.5 ml L����� and 6-7 ml L����� 30 m depth DO. Maps of
estimated likelihood of occurrence generated by NPMR were consistent with
overlayed observations from fishermen, which were not used in the model because
they were limited to presence-only information.
An interdisciplinary approach that incorporates cooperative fisheries research
and ecosystem-based management is necessary for monitoring Humboldt squid in
Oregon. Traditional methods are insufficient because Humboldt squid are data-poor,
highly migratory, and are main predators of many commercially important fisheries in
Oregon. Based on my findings, sightings recorded by fishermen covered a much
larger area over a longer time frame than the scientific survey and observer data, and
excluding their knowledge would have led to a different interpretation of Humboldt
squid distribution and environmental tolerances. Although there is uncertainty in the
data from potential map bias or misidentification of smaller Humboldt squid,
incorporating sightings from fishermen with traditional fisheries research increases the
quantity and quality of information. Cooperative monitoring for Humboldt squid
could include training in species identification and sea condition reporting in
logbooks. Future "invasions" are likely, and more eyes on the water will improve our
understanding of the behavior and impacts of Humboldt squid on coastal resources. / Graduation date: 2013
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Modelagem de mudanças climáticas: do nicho fundamental à conservação da biodiversidade / Climate change modeling: from the fundamental niche to biodiversity conservationFaleiro, Frederico Augusto Martins Valtuille 07 March 2016 (has links)
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Previous issue date: 2016-03-07 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The climate changes are one of the major threats to the biodiversity and it is expected to increase its impact along the 21st century. The climate change affect all levels of the biodiversity from individuals to biomes, reducing the ecosystem services. Despite of this, the prediction of climate change impacts on biodiversity is still a challenge. Overcoming these issues depends on improvements in different aspects of science that support predictions of climate change impact on biodiversity. The common practice to predict the climate change impact consists in formulate ecological niche models based in the current climate and project the changes based in the future climate predicted by the climate models. However, there are some recognized limitations both in the formulation of the ecological niche model and in the use of predictions from the climate models that need to be analyzed. Here, in the first chapter we review the science behind the climate models in order to reduce the knowledge gap between the scientific community that formulate the climate models and the community that use the predictions of these models. We showed that there is not consensus about evaluate the climate models, obtain regional models with higher spatial resolution and define consensual models. However, we gave some guidelines for use the predictions of the climate models. In the second chapter, we tested if the predictions of correlative ecological niche models fitted with presence-absence match the predictions of models fitted with abundance data on the metrics of climate change impact on orchid bees in the Atlantic Forest. We found that the presence-absence models were a partial proxy of change in abundance when the output of the models was continuous, but the same was not true when the predictions were converted to binary. The orchid bees in general will decrease the abundance in the future, but will retain a good amount of suitable sites in the future and the distance to gained climatic suitable areas can be very close, despite of great variation. The change in the species richness and turnover will be mainly in the western and some regions of southern of the Atlantic Forest. In the third chapter, we discussed the drawbacks in using the estimations of realized niche instead the fundamental niche, such as overpredicting the effect of climate change on species’ extinction risk. We proposed a framework based on phylogenetic comparative and missing data methods to predict the dimensions of the fundamental niche of species with missing data. Moreover, we explore sources of uncertainty in predictions of fundamental niche and highlight future directions to overcome current limitations of phylogenetic comparative and missing data methods to improve predictions. We conclude that it is possible to make better use of the current knowledge about species’ fundamental niche with phylogenetic information and auxiliary traits to predict the fundamental niche of poorly-studied species. In the fourth chapter, we used the framework of the chapter three to test the performance of two recent phylogenetic modeling methods to predict the thermal niche of mammals. We showed that PhyloPars had better performance than Phylogenetic Eigenvector Maps in predict the thermal niche. Moreover, the error and bias had similar phylogenetic pattern for both margins of the thermal niche while they had differences in the geographic pattern. The variance in the performance was explained by taxonomic differences and not by methodological aspects. Finally, our models better predicted the upper margin than the lower margin of the thermal niche. This is a good news for predicting the effect of climate change on species without physiological data. We hope our finds can be used to improve the predictions of climate change effect on the biodiversity in future studies and support the political decisions on minimizing the effects of climate change on biodiversity. / As mudanças climáticas são uma das principais ameaças à biodiversidade e é esperado que aumente seu impacto ao longo do século XXI. As mudanças climáticas afetam todos os níveis de biodiversidade, de indivíduos à biomas, reduzindo os serviços ecossistêmicos. Apesar disso, as predições dos impactos das mudanças climáticas na biodiversidade é ainda um desafio. A superação dessas questões depende de melhorias em diferentes aspectos da ciência que dá suporte para predizer o impacto das mudanças climáticas na biodiversidade. A prática comum para predizer o impacto das mudanças climáticas consiste em formular modelos de nicho ecológico baseado no clima atual e projetar as mudanças baseadas no clima futuro predito pelos modelos climáticos. No entanto, existem algumas limitações reconhecidas na formulação do modelo de nicho ecológico e no uso das predições dos modelos climáticos que precisam ser analisadas. Aqui, no primeiro capítulo nós revisamos a ciência por detrás dos modelos climáticos com o intuito de reduzir a lacuna de conhecimentos entre a comunidade científica que formula os modelos climáticos e a comunidade que usa as predições dos modelos. Nós mostramos que não existe consenso sobre avaliar os modelos climáticos, obter modelos regionais com maior resolução espacial e definir modelos consensuais. No entanto, nós damos algumas orientações para usar as predições dos modelos climáticos. No segundo capítulo, nós testamos se as predições dos modelos correlativos de nicho ecológicos ajustados com presença-ausência são congruentes com aqueles ajustados com dados de abundância nas medidas de impacto das mudanças climáticas em abelhas de orquídeas da Mata Atlântica. Nós encontramos que os modelos com presença-ausência foram substitutos parciais das mudanças na abundância quando o resultado dos modelos foi contínuo (adequabilidade), mas o mesmo não ocorreu quando as predições foram convertidas para binárias. As espécies de abelhas, de modo geral, irão diminuir em abundância no futuro, mas reterão uma boa quantidade de locais adequados no futuro e a distância para áreas climáticas adequadas ganhadas podem estar bem próximo, apesar da grande variação. A mudança na riqueza e na substituição de espécies ocorrerá principalmente no Oeste e algumas regiões no sul da Mata Atlântica. No terceiro capítulo, nós discutimos as desvantagens no uso de estimativas do nicho realizado ao invés do nicho fundamental, como superestimar o efeito das mudanças climáticas no risco de extinção das espécies. Nós propomos um esquema geral baseado em métodos filogenéticos comparativos e métodos de dados faltantes para predizer as dimensões do nicho fundamental das espécies com dados faltantes. Além disso, nós exploramos as fontes de incerteza nas predições do nicho fundamental e destacamos direções futuras para superar as limitações atuais dos métodos comparativos filogenéticas e métodos de dados faltantes para melhorar as predições. Nós concluímos que é possível fazer melhor uso do conhecimento atual sobre o nicho fundamental das espécies com informação filogenética e caracteres auxiliares para predizer o nicho fundamental de espécies pouco estudadas. No quarto capítulo, nós usamos o esquema geral do capítulo três para testar a performance de dois novos métodos de modelagem filogenética para predizer o nicho térmico dos mamíferos. Nós mostramos que o “PhyloPars” teve uma melhor performance que o “Phylogenetic Eigenvector Maps” em predizer o nicho térmico. Além disso, o erro e o viés tiveram um padrão filogenético similar para ambas as margens do nicho térmico, enquanto eles apresentaram diferentes padrões espaciais. A variância na performance foi explicada pelas diferenças taxonômicas e não pelas diferenças em aspectos metodológicos. Finalmente, nossos modelos melhor predizem a margem superior do que a margem inferior do nicho térmico. Essa é uma boa notícia para predizer o efeito das mudanças climáticas em espécies sem dados fisiológicos. Nós esperamos que nossos resultados possam ser usados para melhorar as predições do efeito das mudanças climáticas na biodiversidade em estudos futuros e dar suporte para decisões políticas para minimização dos efeitos das mudanças climáticas na biodiversidade.
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Remote sensing representation learning for a species distribution modeling case studyElkafrawy, Sara 08 1900 (has links)
Les changements climatiques et les phénomènes météorologiques extrêmes sont devenus des moteurs importants de changements de la biodiversité, posant une menace pour la perte d’habitat et l’extinction d’espèces. Comprendre l’état actuel de la biodiversité et identifier les zones hautement adaptées (still strugling with this expression, high suitability for who or what?) sont essentiels afin de lutter contre la perte de biodiversité et guider les processus décisionnels en lien avec les études scientifiques (added scientifiques, as in scientific surveys), les mesures de protection et les efforts de restauration.
Les modèles de distribution des espèces (MDE ou SDM en anglais) sont des outils statistiques permettant de prédire la distribution géographique potentielle d’une espèce en fonction de variables environnementales et des données recueillies à cet endroit. Cependant, les MDE conventionnels sont souvent confrontés à des limitations dues à la résolution spatiale et à la couverture restreinte des variables environnementales, lesquelles sont obtenues suite à des mesures au sol ou à l’aide de stations météorologiques.
Pour mieux comprendre la distribution des espèces à des fins de conservation, le défi GeoLifeCLEF 2022 a été organisé. Cette compétiion comprend un vaste ensemble de données composé de 1,6 million géo-observations liées à la présence de 17 000 espèces végétales et animales. L’objectif principal de ce défi est d’explorer le potentiel des données de télédétection afin de prédire la présence d’espèces à des géolocalisations spécifiques.
Dans ce mémoire, nous étudions diverses techniques d’apprentissage automatique et leur performance en lien avec le défi GeoLifeCLEF 2022. Nous explorons l’efficacité d’algorithmes bien connus en apprentissage par transfert, établissons un cadre d’apprentissage non supervisé et étudions les approches d’apprentissage auto-supervisé lors de la phase d’entraînement. Nos résultats démontrent qu’un ajustement fin des encodeurs pré-entraînés sur différents domaines présente les résultats les plus prometteurs lors de la phase de test. / Climate change and extreme weather events have emerged as significant drivers of biodiversity changes, posing a threat of habitat loss and species extinction. Understanding the current state of biodiversity and identifying areas with high suitability for different species are vital in combating biodiversity loss and guiding decision-making processes for protective measures and restoration efforts.
Species distribution models (SDMs) are statistical tools for predicting a species' potential geographic distribution based on environmental variables and occurrence data. However, conventional SDMs often face limitations due to the restricted spatial resolution and coverage of environmental variables derived from ground-based measurements or weather station data.
To better understand species distribution for conservation purposes, the GeoLifeCLEF 2022 challenge was introduced. This competition encompasses a large dataset of 1.6 million geo-observations linked to the presence of 17,000 plant and animal species. The primary objective of this challenge is to explore the potential of remote sensing data in forecasting species' presence at specific geolocations.
In this thesis, we investigate various machine learning techniques and their performance on the GeoLifeCLEF 2022 challenge. We explore the effectiveness of standard transfer learning algorithms, establish an unsupervised learning framework, and investigate self-supervised learning approaches for training. Our findings demonstrate that fine-tuning pre-trained encoders on different domains yields the most promising test set performance results.
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Evaluating threats to the rare butterfly, <i>Pieris virginiensis</i>.Davis, Samantha Lynn 18 May 2015 (has links)
No description available.
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