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141.
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
142.
Itten René Hischier Roland Andrae Anders S. G. Bieser Jan C. T. Cabernard Livia Falke Annemarie Ferreboeuf Hugues Hilty Lorenz M. Keller Regula L. Lees-Perasso Etienne Preist Chris Stucki Matthias 《The International Journal of Life Cycle Assessment》2020,25(10):2093-2098
The International Journal of Life Cycle Assessment - 相似文献
143.
Jenni Nordn Philip J. Harrison Louise Mair Juha Siitonen Anders Lundstrm Oskar Kindvall Tord Snll 《Ecology and evolution》2020,10(6):3079-3089
Understanding spatiotemporal population trends and their drivers is a key aim in population ecology. We further need to be able to predict how the dynamics and sizes of populations are affected in the long term by changing landscapes and climate. However, predictions of future population trends are sensitive to a range of modeling assumptions. Deadwood‐dependent fungi are an excellent system for testing the performance of different predictive models of sessile species as these species have different rarity and spatial population dynamics, the populations are structured at different spatial scales, and they utilize distinct substrates. We tested how the projected large‐scale occupancies of species with differing landscape‐scale occupancies are affected over the coming century by different modeling assumptions. We compared projections based on occupancy models against colonization–extinction models, conducting the modeling at alternative spatial scales and using fine‐ or coarse‐resolution deadwood data. We also tested effects of key explanatory variables on species occurrence and colonization–extinction dynamics. The hierarchical Bayesian models applied were fitted to an extensive repeated survey of deadwood and fungi at 174 patches. We projected higher occurrence probabilities and more positive trends using the occupancy models compared to the colonization–extinction models, with greater difference for the species with lower occupancy, colonization rate, and colonization:extinction ratio than for the species with higher estimates of these statistics. The magnitude of future increase in occupancy depended strongly on the spatial modeling scale and resource resolution. We encourage using colonization–extinction models over occupancy models, modeling the process at the finest resource‐unit resolution that is utilizable by the species, and conducting projections for the same spatial scale and resource resolution at which the model fitting is conducted. Further, the models applied should include key variables driving the metapopulation dynamics, such as the availability of suitable resource units, habitat quality, and spatial connectivity. 相似文献
144.
Anna Juras Edvard Ehler Maciej Chyleński Łukasz Pospieszny Anna Elżbieta Spinek Helena Malmström Maja Krzewińska Krzysztof Szostek Wojciech Pasterkiewicz Marek Florek Stanisław Wilk Barbara Mnich Janusz Kruk Marzena Szmyt Sławomir Kozieł Anders Götherström Mattias Jakobsson Miroslawa Dabert 《American journal of physical anthropology》2021,176(2):223-236
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Animals monitor surrounding dangers independently or cooperatively (synchronized and coordinated vigilance), with independent and synchronized scanning being prevalent. Coordinated vigilance, including unique sentinel behavior, is rare in nature, since it is time‐consuming and limited in terms of benefits. No evidence showed animals adopt alternative vigilance strategies during antipredation scanning yet. Considering the nonindependent nature of both synchronization and coordination, we assessed whether group members could keep alert synchronously or in a coordinated fashion under different circumstance. We studied how human behavior and species‐specific variables impacted individual and collective vigilance of globally threatened black‐necked cranes (Grus nigricollis) and explored behavior‐based wildlife management. We tested both predation risk (number of juveniles in group) and human disturbance (level and distance) effects on individual and collective antipredation vigilance of black‐necked crane families. Adults spent significantly more time (proportion and duration) on scanning than juveniles, and parents with juveniles behaved more vigilant. Both adults and juveniles increased time allocation and duration on vigilance with observer proximity. Deviation between observed and expected collective vigilance varied with disturbance and predation risk from zero, but not significantly so, indicating that an independent vigilance strategy was adopted by black‐necked crane couples. The birds showed synchronized vigilance in low disturbance areas, with fewer juveniles and far from observers; otherwise, they scanned in coordinated fashion. The collective vigilance, from synchronized to coordinated pattern, varied as a function of observer distance that helped us determine a safe distance of 403.75 m for the most vulnerable family groups with two juveniles. We argue that vigilance could constitute a prime indicator in behavior‐based species conservation, and we suggesting a safe distance of at least 400 m should be considered in future tourist management. 相似文献
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Bertil Persson Anders Andersson Björn Hultberg Christer Hansson 《Free radical research》2013,47(2):151-156
Glutathione, the most abundant low-molecular weight thiol in the skin, has been shown to protect the skin from both photobiological and chemical injury. The thiols, glutathione in particular, have also been shown to be crucially involved in defence against contact allergens. Since the levels of extracellular thiol concentrations are important determinants of intracellular thiol status, we have compared the normal concentrations and the redox status of the main low-molecular weight thiol components in the extracellular fluid at the dermo-epidermal junction with the corresponding plasma levels. In their sulfhydryl form, all three thiols, i.e. glutathione, cysteine and homocysteine, were more abundant in experimental skin blister fluid than in plasma, as were the free disulfides of glutathione and homocysteine, whereas the free disulfides of cysteine were about the same in blister fluid and in plasma. Protein mixed disulfide levels were higher in plasma than in blister fluid. The present results provide information concerning the extracellular defence in the skin. 相似文献