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Understanding species-specific relationships with their environment is essential for ecology, biogeography and conservation biology. Moreover, understanding how these relationships change with spatial scale is critical to mitigating potential threats to biodiversity. But methods which measure inter-specific variation in response to environmental parameters that are also generalizable across multiple spatial scales are scarce. We used broad-scale avian citizen science data, over continental Australia, integrated with remotely-sensed products, to produce a measure of urban-tolerance for a given species at a continental-scale. We then compared these urban-tolerances to modelled responses to urbanization at a local-scale, based on systematic sampling within four small cities. For 49 species which had sufficient data for modelling, we found a significant relationship (R2 = 0.51) between continental-scale urbanness and local-scale urbanness. We also found that relatively few citizen science observations (~250) are necessary for reliable estimates of continental-scale species-specific urban scores to predict local-scale response to urbanization. Our approach demonstrates the applicability of broad-scale citizen science data, contrasting both the spatial grain and extent of standard point-count surveys generally only conducted at small spatial scales. Continental-scale responses in Australia are representative of small-scale responses to urbanization among four small cities in Australia, suggesting that our method of producing species-specific urban scores is robust and may be generalized to other locations lacking appropriate data.  相似文献   
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The distribution of the diamines cadaverine and putrescine and of the polyamines spermidine and spermine has been determined in pea seedlings at variou  相似文献   
3.
Identifying which ecological and life history traits influence a species’ tolerance to urbanization is critical to understanding the trajectory of biodiversity in an increasingly urbanizing world. There is evidence for a wide array of contrasting patterns for single trait associations with urbanization. In a continental‐scale analysis, incorporating 477 species and >5 000 000 bird observations, we developed a novel and scalable methodology that evaluated the ecological and life history traits which most influence a species’ adaptability to persist in urban environments. Specifically, we assigned species‐specific scores based on continuous measures of response to urbanization, using VIIRS night‐time light values (i.e. radiance) as a proxy for urbanization. We identified generalized, phylogenetically controlled patterns: bird species which are generalists (i.e. large niche breadth), with large clutch size, and large residual brain size are among the most urban‐tolerant bird species. Conversely, specialized feeding strategies (i.e. insectivores and granivores) were negatively associated with urbanization. Enhancement and persistence of avian biodiversity in urban environments probably relies on protecting, maintaining and restoring diverse habitats serving a range of life history strategies.  相似文献   
4.
A vast range of research applications in biodiversity sciences requires integrating primary species, genetic, or ecosystem data with other environmental data. This integration requires a consideration of the spatial and temporal scale appropriate for the data and processes in question. But a versatile and scale flexible environmental annotation of biodiversity data remains constrained by technical hurdles. Existing tools have streamlined the intersection of occurrence records with gridded environmental data but have remained limited in their ability to address a range of spatial and temporal grains, especially for large datasets. We present the Spatiotemporal Observation Annotation Tool (STOAT), a cloud-based toolbox for flexible biodiversity–environment annotations. STOAT is optimized for large biodiversity datasets and allows user-specified spatial and temporal resolution and buffering in support of environmental characterizations that account for the uncertainty and scale of data and of relevant processes. The tool offers these services for a growing set of near global, remotely sensed, or modeled environmental data, including Landsat, MODIS, EarthEnv, and CHELSA. STOAT includes a user-friendly, web-based dashboard that provides tools for annotation task management and result visualization, linked to Map of Life, and a dedicated R package (rstoat) for programmatic access. We demonstrate STOAT functionality with several examples that illustrate phenological variation and spatial and temporal scale dependence of environmental characteristics of birds at a continental scale. We expect STOAT to facilitate broader exploration and assessment of the scale dependence of observations and processes in ecology.

In ecology and evolution, processes, data collection, and inference or prediction usually occur at different scales in space and time. This study introduces a cloud-based toolbox for the flexible fusion of biodiversity records with remotely sensed and other environmental information that supports an assessment and accounting of such scale dependencies.  相似文献   
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Swim performance is considered a main fitness‐determining trait in many aquatic organisms. Swimming is generally the only way most aquatic prey can escape predation, and swimming capacity is directly linked to food capture, habitat shifts, and reproduction. Therefore, evolutionary studies of swim performance are important to understand adaptation to aquatic environments. Most studies, however, concentrate on the importance of burst‐swim responses to predators, and little is known about its effect on endurance. Even fewer studies associate differences in organism swim capabilities to key gender‐specific responses. In this experiment, we assess the gender‐specific genetic basis of swimming endurance among four different populations of Trinidadian guppies adapted to different predation regimes. Our results show that second‐generation common‐garden females adapted to a low‐predation environment show longer swim endurance than fish adapted to a high‐predation environment. We also find an expected effect of lowered swimming endurance during pregnancy, but interestingly, it did not matter whether the females were in advanced stages of pregnancy, which severely changes body morphology, versus mid‐pregnancy. Males did not show the same trends across populations, and overall had lower swim endurances than female fish combined even when accounting for size differences. Populations recently transplanted from high‐ to low‐predation environments showed similar endurance to natural low‐predation environments in one population but not the other. This study highlights the importance of endurance in the adaptation of aquatic organisms to different predation regimes.  相似文献   
6.
A Triton X-100 acid urea gel system that gives a 2.5- to 3-cm separation of the rabbit globin peaks after 2 h of electrophoresis is described. The relative insensitivity of this method to large amounts of added protein allows a rapid analysis of low specific activity rabbit globins in various cell-free systems (rabbit reticulocyte lysate, wheat germ, duck reticulocyte lysate). These conditions give a similar separation for the globins of several other species. A 3.5-h electrophoresis under these conditions separates all the globin chains of human umbilical cord blood and allows the detection of the altered globin synthetic ratio of α-thalassemia-1 in small samples of cord blood.  相似文献   
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