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1.
J Anim Ecol ; 93(7): 836-848, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38741512

RESUMO

Climate change is altering the timing of seasonal events for many taxa. There is limited understanding of how northward/southward songbird migration follows or is limited by the latitudinal progression of seasonal transitions. Consistent environmental conditions that migrating birds encounter across latitudes likely represent or correlate with important resources or limiting factors for migration. We tested whether migratory passage-observed via radar-consistently tracked land surface variables and phenophases across latitudes in the US Central Flyway in both spring and fall. The daily temperatures, precipitation and vegetation greenness occurring on 10%, 50% and 90% cumulative passage dates changed substantially with latitude, indicating that most migrants experienced rapidly changing conditions as they headed north or south. Temperature did not limit the progression of migration in either season. Peak spring migration in the southern US occurred nearly 40 days after the spring green wave, the northward progression of vegetation growth, but nearly caught up to green-up at 48° N. Spring migration phenology may have evolved to prioritize earlier arrival for breeding. Across all latitudes, peak fall migration coincided with the same land surface phenophase, an interval of 26 days prior to dormancy onset. Migrants may rely on phenological events in vegetation during fall stopovers. Considering that (a) migratory passage tracked fall land surface phenology across latitudes at a continental scale, (b) previous studies at local scales have demonstrated the importance of fruit during fall migratory stopover and (c) fruiting phenology in North America is occurring later over time while fall migration is advancing, the potential for mismatch between fall fruiting and bird migration phenology urgently needs further investigation.


Assuntos
Migração Animal , Estações do Ano , Aves Canoras , Animais , Aves Canoras/fisiologia , Estados Unidos , Mudança Climática , Temperatura
2.
Environ Manage ; 68(4): 477-490, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34386831

RESUMO

Submerged aquatic vegetation (SAV) improves environmental conditions by acting as a sediment stabilizer and nutrient retention tool; therefore, reintroduction of SAV is a common freshwater restoration goal. Initial plant establishment is often difficult in suboptimal conditions, and planting material with specific traits may increase establishment rates. Here we evaluate the variability in plant traits based on collection location. We find consistent differences in traits of plants collected from different natural water bodies, and those differences persist in plants grown from seeds under common garden greenhouse conditions-presumably because of genetic differentiation. In three separate mesocosm experiments, we tested the interactive impacts of collection location and environmental condition (control conditions, reduced light, elevated nutrients, or a combination of reduced light and elevated nutrients) on plant reproduction and on traits that might indicate future restoration success (plant height, number of leaves, and rhizome diameter). In most cases, plant traits at the end of the experiments varied by collection location, environmental condition, and an interaction between the two. The best performing plants also depended on response variable (e.g., plant height or number of new shoots produced). Together these results suggest that unpredictable environmental conditions at restoration sites will make selection of a single high-performing plant source difficult, so we suggest incorporating a diverse set of collection locations to increase the probability of incorporating desirable traits.


Assuntos
Ecossistema , Plantas , Água Doce
3.
Landsc Ecol ; 39(4): 83, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550967

RESUMO

Context: Artificial light at night (ALAN) is increasing worldwide, with many ecological effects. Aerial insectivores may benefit from foraging on insects congregating at light sources. However, ALAN could negatively impact them by increasing nest visibility and predation risk, especially for ground-nesting species like nightjars (Caprimulgidae). Objectives: We tested predictions based on these two alternative hypotheses, potential foraging benefits vs potential predation costs of ALAN, for two nightjar species in British Columbia: Common Nighthawks (Chordeiles minor) and Common Poorwills (Phalaenoptilus nuttallii). Methods: We modeled the relationship between ALAN and relative abundance using count data from the Canadian Nightjar Survey. We distinguished territorial from extra-territorial Common Nighthawks based on their wingboom behaviour. Results: We found limited support for the foraging benefit hypothesis: there was an increase in relative abundance of extra-territorial Common Nighthawks in areas with higher ALAN but only in areas with little to no urban land cover. Common Nighthawks' association with ALAN became negative in areas with 18% or more urban land cover. We found support for the nest predation hypothesis: the were strong negative associations with ALAN for both Common Poorwills and territorial Common Nighthawks. Conclusions: The positive effects of ALAN on foraging nightjars may be limited to species that can forage outside their nesting territory and to non-urban areas, while the negative effects of ALAN on nesting nightjars may persist across species and landscape contexts. Reducing light pollution in breeding habitat may be important for nightjars and other bird species that nest on the ground. Supplementary Information: The online version contains supplementary material available at 10.1007/s10980-024-01875-3.

4.
Trends Ecol Evol ; 39(6): 548-557, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38796352

RESUMO

Systematic evidence syntheses (systematic reviews and maps) summarize knowledge and are used to support decisions and policies in a variety of applied fields, from medicine and public health to biodiversity conservation. However, conducting these exercises in conservation is often expensive and slow, which can impede their use and hamper progress in addressing the current biodiversity crisis. With the explosive growth of large language models (LLMs) and other forms of artificial intelligence (AI), we discuss here the promise and perils associated with their use. We conclude that, when judiciously used, AI has the potential to speed up and hopefully improve the process of evidence synthesis, which can be particularly useful for underfunded applied fields, such as conservation science.


Assuntos
Inteligência Artificial , Biodiversidade , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/métodos
5.
Cureus ; 15(5): e38840, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37303422

RESUMO

Pediatric behavioral health emergencies (BHE) are increasing in prevalence, yet there are no evidence-based guidelines or protocols for prehospital management. The primary objective of this scoping review is to identify prehospital-specific pediatric BHE research and publicly available emergency medical services (EMS) protocols for pediatric BHE. Secondary objectives include identifying the next priorities for research and EMS protocol considerations for children with neurodevelopmental conditions. This is a scoping review comprised of a research literature search for publications from 2012-2022 and an internet search for publicly available EMS protocols from the United States. Included publications contain data on the epidemiology of pediatric BHE or describe prehospital management of pediatric BHE. EMS protocols were included if they had advisements specific to pediatric BHE. A total of 50 research publications and EMS protocols from 43 states were screened. Seven publications and four protocols were included in this study. Research studies indicated an increase in pediatric BHE over the last decade, but few papers discuss current prehospital management (n=4). Two EMS protocols were specific to pediatric BHE or pediatric agitation, and the other two EMS protocols focused on adult populations with integrated pediatric recommendations. All four EMS protocols encouraged nonpharmaceutical interventions prior to the use of pharmacologic restraints. Although there is a substantial rise in pediatric BHE, there is sparse research data and clinical EMS protocols to support best practices for prehospital pediatric BHE management. This scoping review identifies important future research aims to inform best practices for the prehospital management of pediatric BHE.

6.
Sci Total Environ ; 711: 135133, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31837878

RESUMO

Designed ecosystems are built as part of ongoing urban expansion, providing a suite of valued ecosystem services. However, these new ecosystems could also promote disservices by facilitating the colonization and spread of invasive species. We conduct the first assessment of the quantity and invasion of an overlooked designed ecosystem: stormwater ponds. These ponds are commonly recommended for managing urban hydrology, but little is known about their ecology or extent of proliferation. Using a broad-scale survey of pond coverage in Florida, USA, we found that over 76,000 stormwater ponds have been built just in this state, forming 2.7% of total urban land cover. This extensive pondscape of manufactured habitats could facilitate species spread throughout urban areas and into nearby natural waterbodies. We also conducted a survey of the severity of plant invasion in 30 ponds in Gainesville, FL, US across two pond types (dry vs. wet), and a gradient of management intensities (low, medium, high) and pond ages. We unexpectedly found a high number of invasive plant species (28 in just 30 ponds). Ninety-six percent of surveyed ponds contained from one to ten of these species, with ponds exhibiting high turnover in invader composition (i.e., high beta diversity). The bank sections of dry unmanaged ponds exhibited the highest mean invasive species richness (5.8 ± 1.3) and the inundated centers of wet medium managed ponds exhibited the highest mean invasive species cover (34 ± 12%). Invasive plant richness and cover also tended to be greater in dry ponds with higher soil nutrient levels, and in older wet ponds. Therefore, we found that highly maintained and younger wet ponds were the least invaded. Nevertheless, common management practices that limit plant invasions may also limit native species establishment and invasion may increase in the decades following pond construction.


Assuntos
Ecossistema , Lagoas , Florida , Plantas
7.
Ann Bot ; 102(5): 783-93, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18757881

RESUMO

BACKGROUND AND AIMS: Ecotypic differentiation has been explored in numerous plant species, but has been largely ignored in the Orchidaceae. Applying a specific germination protocol for widespread seed sources may be unreliable due to inherent physiological or genetic differences in localized populations. It is crucial to determine whether ecotypic differentiation exists for restoration and conservation programmes. Calopogon tuberosus var. tuberosus, a widespread terrestrial orchid of eastern North America, is a model species to explore ecotypic differences in germination requirements, as this species occupies diverse habitats spanning a wide geographical range. METHODS: Mature seeds were collected from south Florida, north central Florida, three locations in South Carolina, and the upper Michigan peninsula. Effects of three photoperiods (8/16, 12/12, 16/8 h L/D) were examined on asymbiotic in vitro seed germination and seedling development of C. tuberosus. Germination and early development was monitored for 8 weeks, while advanced development was monitored for an additional 8 weeks. In an additional experiment, asymbiotic seed germination and development was monitored for 8 weeks on six culture media (BM-1 terrestrial orchid medium, Knudson C, Malmgrem, half-strength MS, P723, and Vacin and Went). A tetrazolium test for embryo viability was performed. KEY RESULTS: Short days promoted the highest germination among Florida populations, but few differences among photoperiods in other seed sources existed. Different media had little effect on the germination of Michigan and Florida populations, but germination of South Carolina seeds was higher on media with higher calcium and magnesium. Tetrazolium testing confirmed that South Carolina seeds exhibited low viability while viability was higher in Florida seeds. Seed germination and corm formation was rapid in Michigan seeds across all treatments. Michigan seedlings allocated more biomass to corms compared with other seed sources. CONCLUSIONS: Rapid germination and corm formation may be a survival mechanism in response to a compressed growing season in northern populations. Ecotypic differentiation may be occurring based on seed germination and corm formation data.


Assuntos
Meios de Cultura/efeitos da radiação , Germinação/efeitos da radiação , Orchidaceae/classificação , Orchidaceae/efeitos da radiação , Fotoperíodo , Simbiose/efeitos da radiação , Biomassa , Ecossistema , Orchidaceae/embriologia , Orchidaceae/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação , Sementes/crescimento & desenvolvimento , Sementes/efeitos da radiação
8.
Genetics ; 160(2): 381-91, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11861546

RESUMO

The Trf4p/Pol sigma DNA polymerase (formerly Trf4p/Pol kappa) couples DNA replication to the establishment of sister chromatid cohesion. The polymerase is encoded by two redundant homologs in Saccharomyces cerevisiae, TRF4 and TRF5, that together define a fourth essential nuclear DNA polymerase in yeast and probably in all eukaryotes. Here we present a thorough genetic analysis of the founding member of this novel family of DNA polymerases, TRF4. Analyses of mutants carrying 1 of 34 "surface-targeted" alanine scanning mutations in TRF4 have identified those regions required for Pol sigma's essential function, for its role in DNA double-strand break repair, and for its association with chromosomes. The data strongly support the importance of the regions of predicted structural similarity with the Pol beta superfamily as critical for Trf4p/Pol sigma's essential and repair functions. Surprisingly, five lethal mutations lie outside all polymerase homology in a C-terminal region. The protein possesses Mg2+-dependent 3' to 5' exonuclease activity. Cell cycle analysis reveals that Trf4p/Pol sigma associates with chromosomes in G1, S, and G2 phases, but that association is abolished coincident with dissolution of cohesion at the metaphase-to-anaphase transition.


Assuntos
Proteínas Cromossômicas não Histona/genética , DNA Polimerase Dirigida por DNA/genética , Proteínas Nucleares , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Sequência de Aminoácidos , Proteínas Cromossômicas não Histona/fisiologia , Reparo do DNA/genética , Reparo do DNA/fisiologia , DNA Polimerase Dirigida por DNA/fisiologia , Evolução Molecular , Dados de Sequência Molecular , Mutação , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/fisiologia , Homologia de Sequência , Relação Estrutura-Atividade
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