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51.
Jasper Van doninck Mirkka M. Jones Gabriela Zuquim Kalle Ruokolainen Gabriel M. Moulatlet Anders Sirén Glenda Cárdenas Samuli Lehtonen Hanna Tuomisto 《Ecography》2020,43(1):128-137
Species distribution models are required for the research and management of biodiversity in the hyperdiverse tropical forests, but reliable and ecologically relevant digital environmental data layers are not always available. We here assess the usefulness of multispectral canopy reflectance (Landsat) relative to climate data in modelling understory plant species distributions in tropical rainforests. We used a large dataset of quantitative fern and lycophyte species inventories across lowland Amazonia as the basis for species distribution modelling (SDM). As predictors, we used CHELSA climatic variables and canopy reflectance values from a recent basin-wide composite of Landsat TM/ETM+ images both separately and in combination. We also investigated how species accumulate over sites when environmental distances were expressed in terms of climatic or surface reflectance variables. When species accumulation curves were constructed such that differences in Landsat reflectance among the selected plots were maximised, species accumulated faster than when climatic differences were maximised or plots were selected in a random order. Sixty-nine species were sufficiently frequent for species distribution modelling. For most of them, adequate SDMs were obtained whether the models were based on CHELSA data only, Landsat data only or both combined. Model performance was not influenced by species’ prevalence or abundance. Adding Landsat-based environmental data layers overall improved the discriminatory capacity of SDMs compared to climate-only models, especially for soil specialist species. Our results show that canopy surface reflectance obtained by multispectral sensors can provide studies of tropical ecology, as exemplified by SDMs, much higher thematic (taxonomic) detail than is generally assumed. Furthermore, multispectral datasets complement the traditionally used climatic layers in analyses requiring information on environmental site conditions. We demonstrate the utility of freely available, global remote sensing data for biogeographical studies that can aid conservation planning and biodiversity management. 相似文献
52.
Gabriela Montejo‐Kovacevich Timothy Farkas Andrew Beckerman Patrik Nosil 《Ecology and evolution》2020,10(15):8197-8209
Rapid evolution can influence the ecology of populations, communities, and ecosystems, but the importance of evolution for ecological dynamics remains unclear, largely because the contexts in which evolution is powerful are poorly resolved. Here, we carry out a large observational study to test hypotheses about context dependency of eco‐evolutionary patterns previously identified on the stick insect Timema cristinae. Experiments and observations conducted in 2011 and 2012 documented predator‐mediated negative effects of camouflage maladaptation (i.e., evolutionary dynamics) on: (a) T. cristinae abundance and, (b) species richness and abundance of other arthropods. Here we show that camouflage maladaptation does not correlate with T. cristinae abundance and, instead, is associated with increased abundance and species richness of cohabitating arthropods. We furthermore find that plants with high levels of Timema maladaptation tend to have higher foliar nitrogen, that is, higher nutritional value, and more positive mass‐abundance slopes in the coexisting arthropod communities. We propose explanations for the observed contrasting results, such as negative density‐ and frequency‐dependent selection, feedbacks between herbivore abundance and plant nutritional quality, and common effects of predation pressure on selection and prey abundance. Our results demonstrate the utility of observational studies to assess the context dependency of eco‐evolutionary dynamics patterns and provide testable hypotheses for future work. 相似文献
53.
Pauline van Leeuwen Nadia Mykytczuk Gabriela F. Mastromonaco Albrecht I. Schulte‐Hostedde 《Ecology and evolution》2020,10(11):4677-4690
Microbes can have important impacts on their host's survival. Captive breeding programs for endangered species include periods of captivity that can ultimately have an impact on reintroduction success. No study to date has investigated the impacts of captive diet on the gut microbiota during the relocation process of generalist species. This study simulated a captive breeding program with white‐footed mice (Peromyscus leucopus) to describe the variability in gut microbial community structure and composition during captivity and relocation in their natural habitat, and compared it to wild individuals. Mice born in captivity were fed two different diets, a control with dry standardized pellets and a treatment with nonprocessed components that reflect a version of their wild diet that could be provided in captivity. The mice from the two groups were then relocated to their natural habitat. Relocated mice that had the treatment diet had more phylotypes in common with the wild‐host microbiota than mice under the control diet or mice kept in captivity. These results have broad implications for our understanding of microbial community dynamics and the effects of captivity on reintroduced animals, including the potential impact on the survival of endangered species. This study demonstrates that ex situ conservation actions should consider a more holistic perspective of an animal's biology including its microbes. 相似文献
54.
Márcio A. de Sousa Gabriela Rabaioli Rama Claucia F. Volken de Souza Camille E. Granada 《Biotechnology progress》2020,36(2):e2937
The genus Lactobacillus has been widely used in food industry as starter or adjunct culture due to its probiotic features. Its biotechnological features improve the spectrum of uses of lactobacilli, which can affect its applicability directly. In this sense, this literature review gathers information and discusses the biotechnological potential of technological/probiotic lactobacilli aiming to improve food quality and human health. The primary and secondary metabolism generates specific substances, such as organic acids, carbon dioxide, hydrogen peroxide, diacetyl, fatty acids, and bacteriocins, which are determinant due to their probiotic potential, antimicrobial activity, and the development of new food flavors. In order to become industrially and commercially attractive, it is necessary develop a large-scale process with lower production costs. 相似文献
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56.
Jankowska Urszula Skupien-Rabian Bozena Swiderska Bianka Prus Gabriela Dziedzicka-Wasylewska Marta Kedracka-Krok Sylwia 《Neurochemical research》2021,46(8):2097-2111
Neurochemical Research - Although antipsychotics are routinely used in the treatment of schizophrenia for the last decades, their precise mechanism of action is still unclear. In this study, we... 相似文献
57.
R. Aaron Rogers Madeline R. Meyer Kayla M. Stewart Gabriela M. Eyring Aaron M. Fleming Cynthia J. Burrows 《Biopolymers》2021,112(1)
In DNA, i‐motif (iM) folds occur under slightly acidic conditions when sequences rich in 2′‐deoxycytidine (dC) nucleotides adopt consecutive dC self base pairs. The pH stability of an iM is defined by the midpoint in the pH transition (pHT) between the folded and unfolded states. Two different experiments to determine pHT values via circular dichroism (CD) spectroscopy were performed on poly‐dC iMs of length 15, 19, or 23 nucleotides. These experiments demonstrate two points: (1) pHT values were dependent on the titration experiment performed, and (2) pH‐induced denaturing or annealing processes produced isothermal hysteresis in the pHT values. These results in tandem with model iMs with judicious mutations of dC to thymidine to favor particular folds found the hysteresis was maximal for the shorter poly‐dC iMs and those with an even number of base pairs, while the hysteresis was minimal for longer poly‐dC iMs and those with an odd number of base pairs. Experiments to follow the iM folding via thermal changes identified thermal hysteresis between the denaturing and annealing cycles. Similar trends were found to those observed in the CD experiments. The results demonstrate that the method of iM analysis can impact the pHT parameter measured, and hysteresis was observed in the pHT and Tm values. 相似文献
58.
Vanderley Rayane F. Ger Kemal A. Becker Vanessa Bezerra Maria Gabriela T. A. Panosso Renata 《Hydrobiologia》2021,848(4):943-960
Hydrobiologia - While warming and eutrophication have increased the frequency and magnitude of harmful cyanobacterial blooms globally, the scenario for many eutrophic tropical freshwaters is a... 相似文献
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