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1.
Infant Child Dev ; 33(4)2024.
Artículo en Inglés | MEDLINE | ID: mdl-39192872

RESUMEN

The current study explores whether individual differences in the dimensional adjectives (e.g., big, tall) children understand, relates to individual differences in two non-verbal spatial abilities, spatial scaling and mental transformations, in bilingual children. The inclusion of English-Spanish bilingual children broadens the work in this area which has previously focused strictly on English language. Ninety-two English-Spanish bilingual children between 37.65 and 71.87 months (42 male) participated in the study. Results show number of dimensional adjectives preschool children comprehend utilizing a new interactive, tablet-based task relates to performance on non-verbal spatial tasks. This research supports hypothesized relations between spatial language comprehension and spatial abilities, introduces an effective tool for examining spatial language comprehension in young children, and improves generalizability by including a bilingual sample and testing comprehension in both English and Spanish.

2.
Microbiol Spectr ; 12(8): e0081824, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-38869307

RESUMEN

Riverine islands are widespread alluvium wetlands developed in large rivers, and bacterial communities are crucial to their ecological function, yet their assembly processes are rarely addressed. The ecosystem services provided by the middle and the lower Yangtze are primarily threatened by pollution discharge from agricultural land use, and resource overutilization (e.g., embankments), respectively. Here, we assessed bacterial community assembly processes and their drivers within riverine islands in the middle Yangtze River (MR islands) and those in the lower reach (LR islands). A significant distance-decay relationship was observed, although the turnover rate was lower than that of the terrestrial ecosystem with less connectivity. Deterministic and stochastic processes jointly shaped community patterns, and the influence of stochastic increased from 26% in MR islands to 59% for those in LR islands. Meanwhile, the bacterial community in MR islands was controlled more by inorganic nitrogen availability, whereas those in LR islands were governed by pH and EC, although those factors explained a limited fraction of variation in the bacterial community. Potential indicator taxa (affiliated with Nocardioides and Lysobacter) characterized the waterway transport pollution. Overall, our study demonstrated that bacterial community dissimilarity and the importance of dispersal limitation increased concurrently along the flow direction, while distinct local factors further determined bacterial community compositions by selecting habitat-specificity taxa and particularly metabolism function. These findings enhanced our understanding of the mechanisms driving changes in bacterial communities of riverine islands subject to increased anthropogenic impacts.IMPORTANCERivers are among the most threatened ecosystems globally and face multiple stressors related to human activity. However, linkages between microbial diversity patterns and assembly processes in rivers remain unclear, especially in riverine islands developed in large rivers. Our findings reveal that distinct factors result in divergent bacterial community compositions and functional profiles in the riverine islands in the middle Yangtze and those in the lower Yangtze, with substantial differentiation in deterministic and stochastic processes that jointly contribute to bacterial community assemblages. Additionally, keystone species may play important metabolic roles in coping with human-related disturbances. This study provides an improved understanding of relationships between microbial diversity patterns and ecosystem functions under environmental changes in large river ecosystems.


Asunto(s)
Bacterias , Ecosistema , Ríos , Ríos/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , China , Humedales , Microbiota , Biodiversidad , Islas
3.
Dev Sci ; 27(4): e13480, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38321593

RESUMEN

Individual differences in spatial thinking are predictive of children's math and science achievement and later entry into Science, Technology, Engineering, and Mathematics (STEM) disciplines. Little is known about whether parent characteristics predict individual differences in children's spatial thinking. This study aims to understand whether, and to what extent, mother's intrinsic (i.e., mental rotation) and extrinsic (i.e., spatial scaling) spatial ability directly and indirectly, via the variation in home spatial environment, predicts children's intrinsic and extrinsic spatial ability. A total of 165 mothers and their 4-6-year-old children were recruited to participate in a remote video session with an experimenter. Mothers were administered a forced-choice Intrinsic Spatial Toy Preference Task gauging their preference for highly spatial versus less spatial toys and asked questions with the Home Intrinsic Spatial Environmental Questionnaire about the frequency with which they engage their child in spatial activities at home. Mothers completed a Mental Rotations Test and a Spatial Scaling Task adapted for adults. Children were administered the Picture Rotation Task, the Spatial Scaling Task, and the Peabody Picture Vocabulary Test. Structural equation modeling was used to examine direct and indirect, via home spatial environment and toy choices, influences of mother spatial ability on child spatial ability. Contrary to our predictions, we did not find direct, nor indirect, relations between mother and child spatial ability. These findings suggest that researchers should consider alternative conceptualizations of the early home spatial environment beyond the frequency of spatial play in the home. RESEARCH HIGHLIGHTS: The identification of factors that predict individual differences in children's spatial ability is important in order to maximize STEM learning outcomes. Data collection was conducted remotely rather than in traditional preschool or laboratory settings. Contrary to our pre-registered hypotheses, no significant relations between mother spatial ability, the early home spatial environment, and children's development of spatial skills were found. Future research should consider examining the amount of spatial language used in the home or the quality of parent-child interactions during spatial play as potential explanations for individual differences in children's spatial ability.


Asunto(s)
Madres , Humanos , Preescolar , Femenino , Niño , Madres/psicología , Masculino , Percepción Espacial/fisiología , Adulto , Relaciones Madre-Hijo , Desarrollo Infantil/fisiología , Juego e Implementos de Juego , Navegación Espacial/fisiología
4.
Cogn Res Princ Implic ; 8(1): 62, 2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37794290

RESUMEN

The present study examined whether scaling direction and perceptual modality affect children's spatial scaling. Children aged 6-8 years (N = 201) were assigned to a visual, visuo-haptic, and haptic condition in which they were presented with colourful, embossed graphics. In the haptic condition, they were asked to wear a blindfold during the test trials. Across several trials, children were asked to learn about the position of a target in a map and to localize a disc at the same location in a referent space. Scaling factor was manipulated systematically, so that children had to either scale up or scale down spatial information. Their absolute deviations from the correct target location, reversal and signed errors, and response times served as dependent variables. Results revealed higher absolute deviations and response times for the haptic modality as opposed to the visual modality. Children's signed errors, however, showed similar response strategies across the perceptual conditions. Therefore, it seems that a functional equivalence between vision and touch seems to emerge slowly across development for spatial scaling. With respect to scaling directions, findings showed that absolute deviations were affected by scaling factors, with symmetric increases in scaling up and scaling down in the haptic condition. Conversely, children showed an unbalanced pattern in the visual conditions, with higher accuracy in scaling down as opposed to scaling up. Overall, our findings suggest that visibility seems to factor into children's scaling process.


Asunto(s)
Percepción del Tacto , Tacto , Humanos , Niño , Tacto/fisiología , Percepción del Tacto/fisiología , Aprendizaje , Tiempo de Reacción , Servicios de Salud
5.
Sci Total Environ ; 893: 164835, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37321495

RESUMEN

Dissolved organic matter (DOM) in natural ecosystems is intimately associated with microbial communities. However, it remains unclear whether the diversity patterns followed by microbes can be transmitted to DOM compounds. Considering the structural properties of DOM compounds and the roles of microbes in ecosystems, we hypothesized that bacteria tended to be more closely associated with DOM compounds than fungi. To test the above hypothesis and bridge this knowledge gap, the diversity patterns and ecological processes for the DOM compounds, and the bacterial and fungal communities in a mudflat intertidal zone were comparatively investigated. As a result, spatial scaling patterns followed by microbes, including the diversity-area and distance-decay relationships, were also observed for DOM compounds. Lipid-like and aliphatic-like molecules comprised the major DOM compounds associated with environmental factors. Both the alpha- and beta-chemodiversity of DOM compounds were significantly associated with the diversity of bacterial communities, but not fungal communities. Co-occurrence ecological network analysis suggested that DOM compounds were more frequently associated with bacteria than fungi. Further, consistent community assembly patterns were observed for DOM and bacterial communities, but not fungal communities. Integrating multiple lines of evidence, this study demonstrated that bacteria rather than fungi mediated the chemodiversity of DOM in the mudflat intertidal zone. This study elucidates the spatial patterns of complex dissolved organic matter (DOM) pools in the intertidal ecosystem, shedding light on the intricate relationship between DOM compounds and bacterial communities.


Asunto(s)
Materia Orgánica Disuelta , Microbiota , Carbono/química , Bacterias , Hongos
6.
Front Microbiol ; 14: 1152818, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37333641

RESUMEN

Diversity patterns and community assembly of soil microorganisms are essential for understanding soil biodiversity and ecosystem processes. Investigating the impacts of environmental factors on microbial community assembly is crucial for comprehending the functions of microbial biodiversity and ecosystem processes. However, these issues remain insufficiently investigated in related studies despite their fundamental significance. The present study aimed to assess the diversity and assembly of soil bacterial and fungal communities to altitude and soil depth variations in mountain ecosystems by using 16S and ITS rRNA gene sequence analyses. In addition, the major roles of environmental factors in determining soil microbial communities and assembly processes were further investigated. The results showed a U-shaped pattern of the soil bacterial diversity at 0-10 cm soil depth along altitudes, reaching a minimum value at 1800 m, while the fungal diversity exhibited a monotonically decreasing trend with increasing altitude. At 10-20 cm soil depth, the soil bacterial diversity showed no apparent changes along altitudinal gradients, while the fungal Chao1 and phylogenetic diversity (PD) indices exhibited hump-shaped patterns with increasing altitude, reaching a maximum value at 1200 m. Soil bacterial and fungal communities were distinctively distributed with altitude at the same depth of soil, and the spatial turnover rates in fungi was greater than in bacteria. Mantel tests suggested soil physiochemical and climate variables significantly correlated with the ß diversity of microbial community at two soil depths, suggesting both soil and climate heterogeneity contributed to the variation of bacterial and fungal community. Correspondingly, a novel phylogenetic null model analysis demonstrated that the community assembly of soil bacterial and fungal communities were dominated by deterministic and stochastic processes, respectively. The assembly processes of bacterial community were significantly related to the soil DOC and C:N ratio, while the fungal community assembly processes were significantly related to the soil C:N ratio. Our results provide a new perspective to assess the responses of soil microbial communities to variations with altitude and soil depth.

7.
Sci Total Environ ; 885: 163854, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37142009

RESUMEN

Uncovering the mechanisms driving patterns of diversity across space and through time is of critical importance in microbial community ecology. Previous studies suggest that microorganisms also follow the same spatial scaling patterns as macro-organisms. However, it remains unclear whether different microbial functional groups differ in spatial scaling and how different ecological processes may contribute to such differences. In this study, two typical spatial scaling patterns, taxa-area (TAR) and distance-decay relationships (DDR), were investigated for the whole prokaryotic community and seven microbial functional groups using marker genes, including amoA (AOA), amoA (AOB), aprA, dsrB, mcrA, nifH and nirS. Different microbial functional groups harbored different spatial scaling patterns. Microbial functional groups had weaker TAR slope coefficients than the whole prokaryotic community. The archaeal ammonia-oxidizing group, however, displayed a stronger DDR pattern than the bacterial ammonia-oxidizing group. For both TAR and DDR, rare subcommunities were mainly responsible for the observed microbial spatial scaling patterns. Significant associations between environmental heterogeneity and spatial scaling metrics were observed for multiple microbial functional groups. Dispersal limitation, which positively correlated with phylogenetic breadth, was also strongly associated with the strength of microbial spatial scaling. The results demonstrated that environmental heterogeneity and dispersal limitation simultaneously contributed to microbial spatial scaling patterns. This study links microbial spatial scaling patterns with ecological processes, providing mechanistic insights into the typical diversity patterns followed by microbes.


Asunto(s)
Amoníaco , Bacterias , Filogenia , Archaea , Microbiología del Suelo
8.
Appl Environ Microbiol ; 89(3): e0209622, 2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-36815790

RESUMEN

The spatial scaling of biodiversity, such as the taxa-area relationship (TAR) and distance-decay relationship (DDR), is a typical ecological pattern that is followed by both microbes and macrobes in natural ecosystems. Previous studies focusing on microbes mainly aimed to address whether and how different types of microbial taxa differ in spatial scaling patterns, leaving the underlying mechanisms largely untouched. In this study, the spatial scaling of different microbial domains and their associated ecological processes in an intertidal zone were comparatively investigated. The significant spatial scaling of biodiversity could be observed across all microbial domains, including archaea, bacteria, fungi, and protists. Among them, archaea and fungi were found with much stronger DDR slopes than those observed in bacteria and protists. For both TAR and DDR, rare subcommunities were mainly responsible for the observed spatial scaling patterns, except for the DDR of protists and bacteria. This was also evidenced by extending the TAR and DDR diversity metrics to Hill numbers. Further statistical analyses demonstrated that different microbial domains were influenced by different environmental factors and harbored distinct local community assembly processes. Of these, drift was mainly responsible for the compositional variations of bacteria and protists. Archaea were shaped by strong homogeneous selection, whereas fungi were more affected by dispersal limitation. Such differing ecological processes resulted in the domain-level differentiation of microbial spatial scaling. This study links ecological processes with microbial spatial scaling and provides novel mechanistic insights into the diversity patterns of microbes that belong to different trophic levels. IMPORTANCE As the most diverse and numerous life form on Earth, microorganisms play indispensable roles in natural ecological processes. Revealing their diversity patterns across space and through time is of essential importance to better understand the underlying ecological mechanisms controlling the distribution and assembly of microbial communities. However, the diversity patterns and their underlying ecological mechanisms for different microbial domains and/or trophic levels require further exploration. In this study, the spatial scaling of different microbial domains and their associated ecological processes in a mudflat intertidal zone were investigated. The results showed different spatial scaling patterns for different microbial domains. Different ecological processes underlie the domain-level differentiation of microbial spatial scaling. This study links ecological processes with microbial spatial scaling to provide novel mechanistic insights into the diversity patterns of microorganisms that belong to different trophic levels.


Asunto(s)
Bacterias , Microbiota , Bacterias/genética , Archaea , Biodiversidad , Hongos
9.
Mem Cognit ; 50(6): 1201-1214, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35610445

RESUMEN

The current study compared adults' spatial scaling from memory in the visual and haptic domain. Adults (N = 32, ages 19-27 years) were presented with a spatial-scaling task in a visual condition as well as a haptic condition (in which participants were blindfolded throughout the experimental session). In both conditions, they were presented with an embossed graphic including a target (i.e., a map). Then, they were asked to encode this map and to place a disc at the same spot on an empty referent space from memory. Maps had three different sizes whereas the referent space had a constant size, resulting in three different scaling factors (1:1, 1:2, 1:4). Participants' response times and absolute errors were measured. Order of perceptual condition was counterbalanced across participants. Analyses indicated that response times and absolute errors increased linearly with higher scaling factors in the visual as well as the haptic perceptual condition. In analogy to mental imagery research, these results suggest the usage of mental transformation strategies for spatial scaling.


Asunto(s)
Tecnología Háptica , Percepción Espacial , Adulto , Humanos , Tiempo de Reacción/fisiología , Proyectos de Investigación , Percepción Espacial/fisiología , Percepción Visual/fisiología , Adulto Joven
10.
Ecology ; 103(8): e3725, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35416279

RESUMEN

Species abundance distributions (SADs) link species richness with species abundances and are an important tool in the quantitative analysis of ecological communities. Niche-based and sample-based SAD models predict different spatial scaling properties of SAD parameters. However, empirical research on SAD scaling properties is largely missing. Here we extracted percentage cover values of all occurring vascular plants as proxies of their abundance in 1725 10-m2 plots from the GrassPlot database, covering 47 regional data sets of 19 different grasslands and other open vegetation types of the Palaearctic biogeographic realm. For each plot, we fitted the Weibull distribution, a model that is able to effectively mimic other distributions like the log-series and lognormal, to the species-log abundance rank order distribution. We calculated the skewness and kurtosis of the empirical distributions and linked these moments, along with the shape and scale parameters of the Weibull distribution, to plot climatic and soil characteristics. The Weibull distribution provided excellent fits to grassland plant communities and identified four basic types of communities characterized by different degrees of dominance. Shape and scale parameter values of local communities on poorer soils were largely in accordance with log-series distributions. Proportions of subdominant species tended to be lower than predicted by the standard lognormal SAD. Successive accumulation of plots of the same vegetation type yielded nonlinear spatial scaling of SAD moments and Weibull parameters. This scaling was largely independent of environmental correlates and geographic plot position. Our findings caution against simple generalizations about the mechanisms that generate SADs. We argue that in grasslands, lognormal-type SADs tend to prevail within a wider range of environmental conditions, including more extreme habitats such as arid environments. In contrast, log-series distributions are mainly restricted to comparatively species-rich communities on humid and fertile soils.


Asunto(s)
Ecosistema , Pradera , Biodiversidad , Biota , Suelo
11.
Cells ; 11(2)2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-35053364

RESUMEN

During cell division, the mitotic spindle, a macromolecular structure primarily comprised of microtubules, drives chromosome alignment and partitioning between daughter cells. Mitotic spindles can sense cellular dimensions in order to adapt their length and mass to cell size. This scaling capacity is particularly remarkable during early embryo cleavage when cells divide rapidly in the absence of cell growth, thus leading to a reduction of cell volume at each division. Although mitotic spindle size scaling can occur over an order of magnitude in early embryos, in many species the duration of mitosis is relatively short, constant throughout early development and independent of cell size. Therefore, a key challenge for cells during embryo cleavage is not only to assemble a spindle of proper size, but also to do it in an appropriate time window which is compatible with embryo development. How spatial and temporal scaling of the mitotic spindle is achieved and coordinated with the duration of mitosis remains elusive. In this review, we will focus on the mechanisms that support mitotic spindle spatial and temporal scaling over a wide range of cell sizes and cellular contexts. We will present current models and propose alternative mechanisms allowing cells to spatially and temporally coordinate microtubule and mitotic spindle assembly.


Asunto(s)
Microtúbulos/metabolismo , Huso Acromático/metabolismo , Animales , Tamaño de la Célula , Humanos , Modelos Biológicos , Factores de Tiempo
12.
Glob Chang Biol ; 28(3): 770-781, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34719080

RESUMEN

Anthropogenic change has altered the composition and function of ecological communities across the globe. As a result, there is a need for studies examining observed community compositional change and determining whether and how anthropogenic change drivers may be influencing that turnover. In particular, it is also important to determine to what extent community turnover is idiosyncratic or if turnover can be explained by predictable responses across species based on traits or niche characteristics. Here, we measured turnover in avian communities across North America from 1990 to 2016 in the Breeding Bird Survey using an ordination method, and modeled turnover as a function of land use and climate change drivers from local to regional scales. We also examined how turnover may be attributed to species groups, including foraging guilds, trophic groups, migratory distance, and breeding biomes. We found that at local scales, land use change explained a greater proportion of variance in turnover than climate change variables, while as scale increased, trends in temperature explained a greater proportion of variance in turnover. We also found across the study region, turnover could be attributed to one of a handful of species undergoing strong expansions or strong declines over the study time period. We did not observe consistent patterns in compositional change in any trait groups we examined except for those that included previously identified highly influential species. Our results have two important implications: First, the relative importance of different anthropogenic change drivers may vary with scale, which should be considered in studies' modeling impacts of global change on biodiversity. Second, in North American avian communities, individual species undergoing large shifts in population may drive signals in compositional change, and composite community turnover metrics should be carefully selected as a result.


Asunto(s)
Biodiversidad , Aves , Animales , Aves/fisiología , Cambio Climático , Ecosistema , Temperatura
13.
Cogn Process ; 23(2): 319-327, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34962621

RESUMEN

The present study examined differences in adults' spatial-scaling abilities across three perceptual conditions: (1) visual, (2) haptic, and (3) visual and haptic. Participants were instructed to encode the position of a convex target presented in a simple map without a time limit. Immediately after encoding the map, participants were presented with a referent space and asked to place a disc at the same location from memory. All spaces were designed as tactile graphics. Positions of targets varied along the horizontal dimension. The referent space was constant in size while sizes of maps were systematically varied, resulting in three scaling factor conditions: 1:4, 1:2, 1:1. Sixty adults participated in the study (M = 21.18; SD = 1.05). One-third of them was blindfolded throughout the entire experiment (haptic condition). The second group of participants was allowed to see the graphics (visual condition); the third group were instructed to see and touch the graphics (bimodal condition). An analysis of participants' absolute errors showed that participants produced larger errors in the haptic condition as opposed to the visual and bimodal conditions. There was also a significant interaction effect between scaling factor and perceptual condition. In the visual and bimodal conditions, results showed a linear increase in errors with higher scaling factors (which may suggest that adults adopted mental transformation strategies during the spatial scaling process), whereas, in the haptic condition, this relation was quadratic. Findings imply that adults' spatial-scaling performance decreases when visual information is not available.


Asunto(s)
Percepción Espacial , Percepción del Tacto , Adulto , Interfaces Hápticas , Tecnología Háptica , Humanos , Tacto , Percepción Visual
14.
Sci Total Environ ; 798: 149362, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34375268

RESUMEN

The alpine meadow ecosystem, as the main ecosystem of the Qinghai-Tibet Plateau, has been heavily degraded over the past several decades due to overgrazing and climate change. Although soil microorganisms play key roles in the stability and succession of grassland ecosystems, their response to grassland degradation has not been investigated at spatial scale. Here, we systematically analyzed the spatial turnover rates of soil prokaryotic and fungal communities in degraded and undegraded meadows through distance-decay relationship (DDR) and species area relationship (SAR), as well as the community assembly mechanisms behind them. Although the composition and structure of both fungal and prokaryotic communities showed significant changes between undegraded and degraded meadows, steeper spatial turnover rates were only observed in fungi (Degraded Alpine Meadow ß = 0.0142, Undegraded Alpine Meadow ß = 0.0077, P < 0.05). Mantel tests indicated that edaphic variables and vegetation factors showed significant correlations to the ß diversity of fungal community only in degraded meadow, suggesting soil and vegetation heterogeneity both contributed to the variation of fungal community in that system. Correspondingly, a novel phylogenetic null model analysis demonstrated that environmental selection was enhanced in the fungal community assembly process during meadow degradation. Interestingly, dispersal limitation was also enhanced for the fungal community in the degraded meadow, and its relative contribution to other assembly process (i.e. selection and drift) showed a significant linear increase with spatial distance, suggesting that dispersal limitation played a greater role as distance increased. Our findings indicated the spatial scaling of the fungal community is altered during meadow degradation by both niche selection and dispersal limitation. This study provides a new perspective for the assessment of soil microbial responses to vegetation changes in alpine areas.


Asunto(s)
Pradera , Micobioma , Ecosistema , Filogenia , Suelo , Microbiología del Suelo , Tibet
15.
Mol Ecol ; 30(4): 1072-1085, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33320382

RESUMEN

Although many studies have investigated the spatial scaling of microbial communities living in surface soils, very little is known about the patterns within deeper strata, nor is the mechanism behind them. Here, we systematically assessed spatial scaling of prokaryotic biodiversity within three different strata (Upper: 0-20 cm, Middle: 20-40 cm, and Substratum: 40-100 cm) in a typical grassland by examining both distance-decay (DDRs) and species-area relationships (SARs), taxonomically and phylogenetically, as well as community assembly processes. Each layer exhibited significant biogeographic patterns in both DDR and SAR (p < .05), with taxonomic turnover rates higher than phylogenetic ones. Specifically, the spatial turnover rates, ß and z values, respectively, ranged from 0.016 ± 0.005 to 0.023 ± 0.005 and 0.065 ± 0.002 to 0.077 ± 0.004 across soil strata, and both increased with depth. Moreover, the prokaryotic community in grassland soils assembled mainly according to deterministic rather than stochastic mechanisms. By using normalized stochasticity ratio (NST) based on null model, the relative importance of deterministic ratios increased from 48.0 to 63.3% from Upper to Substratum, meanwhile a phylogenetic based method revealed average ßNTI also increased with depth, from -5.29 to 19.5. Using variation partitioning and distance approaches, both geographic distance and soil properties were found to strongly affect biodiversity structure, the proportions increasing with depth, but spatial distance was always the main underlying factor. These indicated increasingly deterministic proportions in accelerating turnover rates for spatial assembly of prokaryotic biodiversity. Our study provided new insights on biogeography in different strata, revealing importance of assembly patterns and mechanisms of prokaryote communities in below-surface soils.


Asunto(s)
Biodiversidad , Microbiota , Microbiota/genética , Filogenia , Suelo , Microbiología del Suelo
16.
Ann Bot ; 126(4): 539-557, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32173742

RESUMEN

Agent-based modelling (ABM) has become an established methodology in many areas of biology, ranging from the cellular to the ecological population and community levels. In plant science, two different scales have predominated in their use of ABM. One is the scale of populations and communities, through the modelling of collections of agents representing individual plants, interacting with each other and with the environment. The other is the scale of the individual plant, through the modelling, by functional-structural plant models (FSPMs), of agents representing plant building blocks, or metamers, to describe the development of plant architecture and functions within individual plants. The purpose of this review is to show key results and parallels in ABM for growth, mortality, carbon allocation, competition and reproduction across the scales from the plant organ to populations and communities on a range of spatial scales to the whole landscape. Several areas of application of ABMs are reviewed, showing that some issues are addressed by both population-level ABMs and FSPMs. Continued increase in the relevance of ABM to environmental science and management will be helped by greater integration of ABMs across these two scales.


Asunto(s)
Carbono , Plantas , Ecología
17.
Dev Sci ; 23(4): e12909, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31599470

RESUMEN

There is evidence that spatial thinking is malleable, and that spatial and mathematical skills are associated (Mix et al. [2016] Journal of Experimental Psychology: General, 145, 1206; Mix et al. [2017] Journal of Cognition and Development, 18, 465; Uttal et al. [2013] Psychological Bulletin, 139, 352). However, few studies have investigated transfer of spatial training gains to mathematics outcomes in children, and no known studies have compared different modes of spatial instruction (explicit vs. implicit instruction). Based on a sample of 250 participants, this study compared the effectiveness of explicit and implicit spatial instruction in eliciting near transfer (to the specific spatial skills trained), intermediate transfer (to untrained spatial skills) and far transfer (to mathematics domains) at age 8. Spatial scaling and mental rotation skills were chosen as training targets as previous studies have found, and proposed explanations for, associations between these skills and mathematics in children of this age (Journal of Experimental Psychology: General, 145, 2016 and 1206). In this study, spatial training led to near, intermediate and far transfer of gains. Mental visualization and proportional reasoning were proposed to explain far transfer from mental rotation and spatial scaling skills respectively. For most outcomes, except for geometry, there was no difference in the effectiveness of implicit (practice with feedback) compared to explicit instruction (instructional videos). From a theoretical perspective, the study identified a specific causal effect of spatial skills on mathematics skills in children. Practically, the results also highlight the potential of instructional videos as a method of introducing spatial thinking into the classroom.


Asunto(s)
Matemática , Solución de Problemas , Percepción Espacial , Niño , Cognición , Femenino , Humanos , Masculino , Matemática/educación
18.
Ecol Evol ; 9(9): 5338-5347, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31110683

RESUMEN

To quantify and assess the processes underlying community assembly and driving tree species abundance distributions(SADs) with spatial scale variation in two typical subtropical secondary forests in Dashanchong state-owned forest farm, two 1-ha permanent study plots (100-m × 100-m) were established. We selected four diversity indices including species richness, Shannon-Wiener, Simpson and Pielou, and relative importance values to quantify community assembly and biodiversity. Empirical cumulative distribution and species accumulation curves were utilized to describe the SADs of two forests communities trees. Three types of models, including statistic model (lognormal and logseries model), niche model (broken-stick, niche preemption, and Zipf-Mandelbrodt model), and neutral theory model, were estimated by the fitted SADs. Simulation effects were tested by Akaike's information criterion (AIC) and Kolmogorov-Smirnov test. Results found that the Fagaceae and Anacardiaceae families were their respective dominance family in the evergreen broad-leaved and deciduous mixed communities. According to original data and random sampling predictions, the SADs were hump-shaped for intermediate abundance classes, peaking between 8 and 32 in the evergreen broad-leaved community, but this maximum increased with size of total sampled area size in the deciduous mixed community. All niche models could only explain SADs patterns at smaller spatial scales. However, both the neutral theory and purely statistical models were suitable for explaining the SADs for secondary forest communities when the sampling plot exceeded 40 m. The results showed the SADs indicated a clear directional trend toward convergence and similar predominating ecological processes in two typical subtropical secondary forests. The neutral process gradually replaced the niche process in importance and become the main mechanism for determining SADs of forest trees as the sampling scale expanded. Thus, we can preliminarily conclude that neutral processes had a major effect on biodiversity patterns in these two subtropical secondary forests but exclude possible contributions of other processes.

19.
Cogn Process ; 20(4): 431-440, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31054026

RESUMEN

The current study investigated adults' spatial-scaling abilities using a haptic localization task. As a first aim, we examined the strategies used to solve this haptic task. Secondly, we explored whether irrelevant visual information influenced adults' spatial-scaling performance. Thirty-two adults were asked to locate targets as presented in maps on a larger or same-sized referent space. Maps varied in size in accordance with different scaling factors (1:4, 1:2, 1:1), whereas the referent space was constant in size throughout the experimental session. The availability of irrelevant, non-informative vision was manipulated by blindfolding half of the participants prior to the experiment (condition without non-informative vision), whereas the other half were able to see their surroundings with the stimuli being hidden behind a curtain (condition with non-informative vision). Analyses with absolute errors (after correcting for reversal errors) as the dependent variable revealed a significant interaction of the scaling factor and non-informative vision condition. Adults in the blindfolded condition showed constant errors and response times irrespective of scaling factor. Such a response pattern indicates the usage of relative strategies. Adults in the curtain condition showed a linear increase in errors with higher scaling factors, whereas their response times remained constant. This pattern of results supports the usage of absolute strategies or mental transformation strategies. Overall, our results indicate different scaling strategies depending on the availability of non-informative vision, highlighting the strong influence of (even irrelevant) vision on adults' haptic processing.


Asunto(s)
Percepción Espacial , Percepción Visual , Adulto , Femenino , Humanos , Tiempo de Reacción
20.
Trends Ecol Evol ; 33(7): 549-564, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29807839

RESUMEN

Evidence is increasing for positive effects of α-diversity on ecosystem functioning. We highlight here the crucial role of ß-diversity - a hitherto underexplored facet of biodiversity - for a better process-level understanding of biodiversity change and its consequences for ecosystems. A focus on ß-diversity has the potential to improve predictions of natural and anthropogenic influences on diversity and ecosystem functioning. However, linking the causes and consequences of biodiversity change is complex because species assemblages in nature are shaped by many factors simultaneously, including disturbance, environmental heterogeneity, deterministic niche factors, and stochasticity. Because variability and change are ubiquitous in ecosystems, acknowledging these inherent properties of nature is an essential step for further advancing scientific knowledge of biodiversity-ecosystem functioning in theory and practice.


Asunto(s)
Biodiversidad , Ecosistema
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