Journal articles: 'Spatial and temporal partitioning'

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Stewart-Koster, Ben, Mark J. Kennard, Bronwyn D. Harch, Fran Sheldon, Angela H. Arthington, and Bradley J. Pusey. "Partitioning the variation in stream fish assemblages within a spatio-temporal hierarchy." Marine and Freshwater Research 58, no. 7 (2007): 675. http://dx.doi.org/10.1071/mf06183.

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This paper describes the relative influence of (i) landscape scale environmental and hydrological factors, (ii) local scale environmental conditions including recent flow history, and (iii) spatial effects (proximity of sites to one another), on the spatial and temporal variation in local freshwater fish assemblages in the Mary River, south-eastern Queensland, Australia. Using canonical correspondence analysis, each of the three sets of variables explained similar amounts of variation in fish assemblages (ranging from 44 to 52%). Variation in fish assemblages was partitioned into eight unique components: pure environmental, pure spatial, pure temporal, spatially structured environmental variation, temporally structured environmental variation, spatially structured temporal variation, the combined spatial/temporal component of environmental variation and unexplained variation. The total variation explained by these components was 65%. The combined spatial/temporal/environmental component explained the largest component (30%) of the total variation in fish assemblages, whereas pure environmental (6%), temporal (9%) and spatial (2%) effects were relatively unimportant. The high degree of intercorrelation between the three different groups of explanatory variables indicates that our understanding of the importance to fish assemblages of hydrological variation (often highlighted as the major structuring force in river systems) is dependent on the environmental context in which this role is examined.

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Arias‐Robledo, G., J. R. Stevens, and R. Wall. "Spatial and temporal habitat partitioning by calliphorid blowflies." Medical and Veterinary Entomology 33, no. 2 (December 19, 2018): 228–37. http://dx.doi.org/10.1111/mve.12354.

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Albrecht, M., and N. J. Gotelli. "Spatial and temporal niche partitioning in grassland ants." Oecologia 126, no. 1 (January 2001): 134–41. http://dx.doi.org/10.1007/s004420000494.

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Simanonok, Michael P., and Laura A. Burkle. "Partitioning interaction turnover among alpine pollination networks: spatial, temporal, and environmental patterns." Ecosphere 5, no. 11 (November 2014): art149. http://dx.doi.org/10.1890/es14-00323.1.

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Udyawer, Vinay, Colin A. Simpfendorfer, Michelle R. Heupel, and Timothy D. Clark. "Temporal and spatial activity‐associated energy partitioning in free‐swimming sea snakes." Functional Ecology 31, no. 9 (May 15, 2017): 1739–49. http://dx.doi.org/10.1111/1365-2435.12882.

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Bell, Dorothy M., and Peter J. Clarke. "Seed-bank dynamics of Eleocharis: can spatial and temporal variability explain habitat segregation?" Australian Journal of Botany 52, no. 1 (2004): 119. http://dx.doi.org/10.1071/bt03024.

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Four Eleocharis species exhibit habitat partitioning in both extant vegetation and in the soil seed bank of upland temporary wetlands on the Northern Tablelands of New South Wales. Explanations for this partitioning were sought in seed-bank dynamics at three shore levels in two wetlands. Habitat partitioning (zonation) was explained in part by seedling recruitment but not by either persistence of seeds in the soil or by dormancy patterns. All four species recruited at wetland edges but only the deepwater species, Eleocharis sphacelata, recruited in deeper water. Viability of buried seeds was consistently high and species had very low decay rates and half-lives greater than 50 years. Two types of dormancy patterns with burial were shown. Most seeds of Eleocharis sphacelata and E. pusilla were non-dormant after a 3-month burial, whereas for E. acuta and E. dietrichiana seed germination percentages gradually increased over a number of years. These two dormancy patterns may contribute to coexistence, since coexistence is enhanced by a long-lived resistant phase in the life history of species and by temporal variability in germination. There were also spatial inconsistencies in patterns of dormant fractions. Burial in the deeper zones of the marsh-like Billybung Lagoon had an inhibitory effect both on germinability and on germination rates of E. acuta and E. dietrichiana seeds. All but E. acuta showed some degree of seasonal dormancy, but this pattern was also not consistent in space. Explanations for zonation should concentrate on other life-history phases, such as dispersal and seedling survival.

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Piet, G. J., J. S. Pet, WAHP Guruge, J. Vijverberg, and WLT Van Densen. "Resource partitioning along three niche dimensions in a size-structured tropical fish assemblage." Canadian Journal of Fisheries and Aquatic Sciences 56, no. 7 (July 1, 1999): 1241–54. http://dx.doi.org/10.1139/f99-033.

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In Tissawewa, a tropical reservoir, the size-specific resource use of the 10 most important fish species was determined along three dimensions: trophic, spatial, and temporal. During this study, a drought occurred distinguishing two periods before and after the drought that differed markedly in availability of resources and fish biomass. In this study, differences in resource use between the two periods are presented together with their consequence on the partitioning of resources. A different approach is introduced into the calculation of niche breadth and niche overlap incorporating size-specific differences in resource use and interactions between resource dimensions. Comparison with conventional measures of niche breadth and niche overlap shows that conventional measures often misrepresent interactions between species. Condition and biomass were used as indicators of a species' fitness, and it is shown that fitness of most species is governed by the availability of resources and partitioning of these resources is an important mechanism allowing potential competitors to coexist. Resource partitioning along the trophic dimension was more important than along the spatial or temporal dimension.

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Mandre, Malle, Hardi Tullus, and Jaan Klõšeiko. "Partitioning Of Carbohydrates And Biomass Of Needles In Scots Pine Canopy." Zeitschrift für Naturforschung C 57, no. 3-4 (April 1, 2002): 296–302. http://dx.doi.org/10.1515/znc-2002-3-417.

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The study was aimed at the quantitative evaluation of the temporal and spatial partitioning of non-structural carbohydrates and needle biomass in a canopy of Scots pine (Pinus sylvestris L.) growing in a Myrtillus site type forest stand (predominant in Estonia). The tree canopy was divided into ten equal layers and the material for the spatial partitioning of the investigated characteristics was sampled from all layers. Our findings revealed a significant variation in morphology and in the partitioning of carbohydrates in needles in different layers of the canopy. The study of the temporal dynamics of carbohydrates showed that starch content in needles started to increase in early spring before budbreak, which was accompanied by a decline in soluble carbohydrates. In October, the starch content of needles was low, but the concentration of soluble sugars started to increase attaining a maximum in winter. Regression analysis indicated that before budbreak, the partitioning of soluble sugars in different canopy layers was relatively weakly correlated with the height of the layer; however, a strong correlation was observed for starch. In autumn, when the growth of trees stopped and daily temperatures decreased, the allocation of soluble sugars was correlated with the height of the canopy layer

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Golodets, Carly, Jaime Kigel, and Marcelo Sternberg. "Plant diversity partitioning in grazed Mediterranean grassland at multiple spatial and temporal scales." Journal of Applied Ecology 48, no. 5 (June 6, 2011): 1260–68. http://dx.doi.org/10.1111/j.1365-2664.2011.02031.x.

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Borovec, Jakub, Dagmara Sirová, Petra Mošnerová, Eliška Rejmánková, and Jaroslav Vrba. "Spatial and temporal changes in phosphorus partitioning within a freshwater cyanobacterial mat community." Biogeochemistry 101, no. 1-3 (June 17, 2010): 323–33. http://dx.doi.org/10.1007/s10533-010-9488-4.

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Tyne, Julian A., David W. Johnston, Fredrik Christiansen, and Lars Bejder. "Temporally and spatially partitioned behaviours of spinner dolphins: implications for resilience to human disturbance." Royal Society Open Science 4, no. 1 (January 2017): 160626. http://dx.doi.org/10.1098/rsos.160626.

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Selective forces shape the evolution of wildlife behavioural strategies and influence the spatial and temporal partitioning of behavioural activities to maximize individual fitness. Globally, wildlife is increasingly exposed to human activities which may affect their behavioural activities. The ability of wildlife to compensate for the effects of human activities may have implications for their resilience to disturbance. Resilience theory suggests that behavioural systems which are constrained in their repertoires are less resilient to disturbance than flexible systems. Using behavioural time-series data, we show that spinner dolphins ( Stenella longirostris ) spatially and temporally partition their behavioural activities on a daily basis. Specifically, spinner dolphins were never observed foraging during daytime, where resting was the predominant activity. Travelling and socializing probabilities were higher in early mornings and late afternoons when dolphins were returning from or preparing for nocturnal feeding trips, respectively. The constrained nature of spinner dolphin behaviours suggests they are less resilient to human disturbance than other cetaceans. These dolphins experience the highest exposure rates to human activities ever reported for any cetaceans. Over the last 30 years human activities have increased significantly in Hawaii, but the spinner dolphins still inhabit these bays. Recent abundance estimates (2011 and 2012) however, are lower than all previous estimates (1979–1981, 1989–1992 and 2003), indicating a possible long-term impact. Quantification of the spatial and temporal partitioning of wildlife behavioural schedules provides critical insight for conservation measures that aim to mitigate the effects of human disturbance.

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Wathen, Gus, Jacob E. Allgeier, Nicolaas Bouwes, Michael M. Pollock, Daniel E. Schindler, and Chris E. Jordan. "Beaver activity increases habitat complexity and spatial partitioning by steelhead trout." Canadian Journal of Fisheries and Aquatic Sciences 76, no. 7 (July 2019): 1086–95. http://dx.doi.org/10.1139/cjfas-2018-0171.

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Freshwater habitat restoration is a major conservation objective, motivating efforts to restore habitat complexity and quality for fishes. Restoration based on the engineering activities of beavers (Castor canadensis) increases fish habitat complexity, but how this affects fish habitat use and movement behaviours is not well known. We used a network of passive integrated transponder antennas to quantify small-scale movement and microhabitat use of 175 individual juvenile steelhead (Oncorhynchus mykiss) in a stream channel with a complex bathymetric profile resulting from a beaver impoundment and in a simplified channel devoid of beaver activity. Our results show that juvenile steelhead exploit microhabitat heterogeneity by employing a range of behaviours that maximizes available habitat via spatial and temporal partitioning among individuals. These results suggest spatial resource partitioning as a potential mechanism for the previously established positive correlations among steelhead density, survival, and production with beaver-based restoration within the study watershed. More broadly, our findings provide insight as to how populations can exploit habitat complexity through spatial partitioning that can be informative for planning restoration and management actions.

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Taylor, Matthew D. "Spatial and temporal patterns of habitat use by three estuarine species of mysid shrimp." Marine and Freshwater Research 59, no. 9 (2008): 792. http://dx.doi.org/10.1071/mf07247.

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The mysids Rhopalopthalmus egregius, Haplostylus dakini and Doxomysis australiensis are abundant yet unstudied omnivorous crustaceans in Australian estuaries. Habitat use and population dynamics were investigated for these species over spring and summer in the Tweed River, Australia, to explore their ecological role in estuarine ecosystems. Overall, mysids were concentrated in shallow unvegetated and deep unvegetated estuarine habitats. H. dakini were most abundant in shallow and deep bare habitats at night, whereas R. egregius were most abundant in deep bare habitats during the night. D. australiensis were present across all habitats in the night, but negligible numbers were present during the day. Significantly greater numbers of R. egregius and D. australiensis were sampled during the new moon, compared with the full moon. Significantly larger R. egregius and D. australiensis individuals were present in benthic habitats at night, indicating possible partitioning of habitat for juvenile and adult subpopulations. Adaptive foraging strategies and habitat use facilitates the coexistence of sympatric mysid species, H. dakini and R. egregius, and within-species habitat partitioning allowed juvenile R. egregius to avoid interaction with adult R. egregius. The observed dynamics minimize inter- and intra-specific predation between mysids, and by other predators, while optimizing access to key trophic resources.

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Petrozzi, Fabio, Edem A. Eniang, Nioking Amadi, Godfrey C. Akani, and Luca Luiselli. "Temporal and spatial segregation in an assemblage of Afrotropical subterranean snakes." Amphibia-Reptilia 35, no. 3 (2014): 345–53. http://dx.doi.org/10.1163/15685381-00002959.

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Niche partititioning patterns have not been studied so far in burrowing tropical snakes of the families Typhlopidae and Leptotyphlopidae. In this study, we analyze temporal (= monthly activity) and spatial (= habitat use) niche dimensions in three species of burrowing snakes from the Niger Delta, Nigeria. Null model analyses, using two randomization algorithms and 30 000 Monte Carlo permutations, showed that there was random resource partitioning patterns as for the spatial niche dimension. One species (Rhinotyphlops punctatus) clearly dominated in the sample, and appeared to be more habitat generalist than the others. All three species showed an uneven monthly activity, with peaks occurring by wet season, and statistically significant positive correlations between mean monthly rainfall and number of captured snakes. However, there were significantly negative correlations between mean monthly temperature and number of captured snakes in two of the three species (Rhinotyphlops congestus;Leptotyphlopscfr.sundewalli).

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Xie, Zunyi, Alfredo Huete, Natalia Restrepo-Coupe, Xuanlong Ma, Rakhesh Devadas, and Graziella Caprarelli. "Spatial partitioning and temporal evolution of Australia's total water storage under extreme hydroclimatic impacts." Remote Sensing of Environment 183 (September 2016): 43–52. http://dx.doi.org/10.1016/j.rse.2016.05.017.

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Schulz, Jan, Myron A. Peck, Kristina Barz, Jörn Oliver Schmidt, Frank C. Hansen, Janna Peters, Jasmin Renz, et al. "Spatial and temporal habitat partitioning by zooplankton in the Bornholm Basin (central Baltic Sea)." Progress in Oceanography 107 (December 2012): 3–30. http://dx.doi.org/10.1016/j.pocean.2012.07.002.

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Anderson, M. J., and N. A. Cribble. "Partitioning the variation among spatial, temporal and environmental components in a multivariate data set." Austral Ecology 23, no. 2 (April 1998): 158–67. http://dx.doi.org/10.1111/j.1442-9993.1998.tb00713.x.

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Tatsumi, Shinichi, Ryosuke Iritani, and Marc W. Cadotte. "Temporal changes in spatial variation: partitioning the extinction and colonisation components of beta diversity." Ecology Letters 24, no. 5 (March 14, 2021): 1063–72. http://dx.doi.org/10.1111/ele.13720.

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Naranjo, Valery, Jesús Angulo, Antonio Albiol, Jose M. Mossi, Alberto Albiol, and Soledad Gómez. "GRADUAL TRANSITION DETECTION FOR VIDEO PARTITIONING USING MORPHOLOGICAL OPERATORS." Image Analysis & Stereology 26, no. 2 (May 3, 2011): 51. http://dx.doi.org/10.5566/ias.v26.p51-61.

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Temporal segmentation of video data for partitioning the sequence into shots is a prerequisite in many applications: automatic video indexing and editing, old flm restoration, perceptual coding, etc. The detection of abrupt transitions or cuts has been thoroughly studied in previous works. In this paper we present a scheme to identify the most common gradual transitions, i.e., dissolves and wipes, which relies on mathematical morphology operators. The approach is restricted to fast techniques which require low computation (without motion estimation and adapted to compressed sequences) and are able to cope with random brightness variations (often occurring in old flms). The present study illustrates how the morphological operators can be used to analyze temporal series for detecting particular events, either working directly on the 1D signal or building an intermediate 2D image from the 1D signals to take advantage of the spatial operators.

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Magurran, A. E., and P. A. Henderson. "More than the sum of the parts: annual partitioning within spatial guilds underpins community regulation." Proceedings of the Royal Society B: Biological Sciences 285, no. 1883 (July 18, 2018): 20180659. http://dx.doi.org/10.1098/rspb.2018.0659.

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To withstand the pressures of a rapidly changing world, resilient ecosystems should exhibit compensatory dynamics, including uncorrelated temporal shifts in population sizes. The observation that diversity is maintained through time in many systems is evidence that communities are indeed regulated and stabilized, yet empirical observations suggest that positive covariance in species abundances is widespread. This paradox could be resolved if communities are composed of a number of ecologically relevant sub-units in which the members compete for resources, but whose abundances fluctuate independently. Such modular organization could explain community regulation, even when the community as a whole appears synchronized. To test this hypothesis, we quantified temporal synchronicity in annual population abundances within spatial guilds in an estuarine fish assemblage that has been monitored for 36 years. We detected independent fluctuations in annual abundances within guilds. By contrast, the assemblage as a whole exhibited temporal synchronicity—an outcome linked to the dynamics of guild dominants, which were synchronized with each other. These findings underline the importance of modularity in explaining community regulation and highlight the need to protect assemblage composition and structure as well as species richness.

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Borges, Heraldo, Murillo Dutra, Amin Bazaz, Rafaelli Coutinho, Fábio Perosi, Fábio Porto, Florent Masseglia, Esther Pacitti, and Eduardo Ogasawara. "Spatial-time motifs discovery." Intelligent Data Analysis 24, no. 5 (September 30, 2020): 1121–40. http://dx.doi.org/10.3233/ida-194759.

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Discovering motifs in time series data has been widely explored. Various techniques have been developed to tackle this problem. However, when it comes to spatial-time series, a clear gap can be observed according to the literature review. This paper tackles such a gap by presenting an approach to discover and rank motifs in spatial-time series, denominated Combined Series Approach (CSA). CSA is based on partitioning the spatial-time series into blocks. Inside each block, subsequences of spatial-time series are combined in a way that hash-based motif discovery algorithm is applied. Motifs are validated according to both temporal and spatial constraints. Later, motifs are ranked according to their entropy, the number of occurrences, and the proximity of their occurrences. The approach was evaluated using both synthetic and seismic datasets. CSA outperforms traditional methods designed only for time series. CSA was also able to prioritize motifs that were meaningful both in the context of synthetic data and also according to seismic specialists.

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Lorkowski, P., and T. Brinkhoff. "COMPRESSION AND PROGRESSIVE RETRIEVAL OF MULTI-DIMENSIONAL SENSOR DATA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B2 (June 7, 2016): 27–33. http://dx.doi.org/10.5194/isprsarchives-xli-b2-27-2016.

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Since the emergence of sensor data streams, increasing amounts of observations have to be transmitted, stored and retrieved. Performing these tasks at the granularity of single points would mean an inappropriate waste of resources. Thus, we propose a concept that performs a partitioning of observations by spatial, temporal or other criteria (or a combination of them) into data segments. We exploit the resulting proximity (according to the partitioning dimension(s)) within each data segment for compression and efficient data retrieval. While in principle allowing lossless compression, it can also be used for progressive transmission with increasing accuracy wherever incremental data transfer is reasonable. In a first feasibility study, we apply the proposed method to a dataset of ARGO drifting buoys covering large spatio-temporal regions of the world´s oceans and compare the achieved compression ratio to other formats.

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Lorkowski, P., and T. Brinkhoff. "COMPRESSION AND PROGRESSIVE RETRIEVAL OF MULTI-DIMENSIONAL SENSOR DATA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B2 (June 7, 2016): 27–33. http://dx.doi.org/10.5194/isprs-archives-xli-b2-27-2016.

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Since the emergence of sensor data streams, increasing amounts of observations have to be transmitted, stored and retrieved. Performing these tasks at the granularity of single points would mean an inappropriate waste of resources. Thus, we propose a concept that performs a partitioning of observations by spatial, temporal or other criteria (or a combination of them) into data segments. We exploit the resulting proximity (according to the partitioning dimension(s)) within each data segment for compression and efficient data retrieval. While in principle allowing lossless compression, it can also be used for progressive transmission with increasing accuracy wherever incremental data transfer is reasonable. In a first feasibility study, we apply the proposed method to a dataset of ARGO drifting buoys covering large spatio-temporal regions of the world´s oceans and compare the achieved compression ratio to other formats.

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Gosselink, Todd E., Timothy R. Van Deelen, Richard E. Warner, and Mark G. Joselyn. "Temporal Habitat Partitioning and Spatial Use of Coyotes and Red Foxes in East-Central Illinois." Journal of Wildlife Management 67, no. 1 (January 2003): 90. http://dx.doi.org/10.2307/3803065.

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Wu, X., R. Zurita-Milla, M. J. Kraak, and E. Izquierdo-Verdiguier. "CLUSTERING-BASED APPROACHES TO THE EXPLORATION OF SPATIO-TEMPORAL DATA." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-2/W7 (September 14, 2017): 1387–91. http://dx.doi.org/10.5194/isprs-archives-xlii-2-w7-1387-2017.

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As one spatio-temporal data mining task, clustering helps the exploration of patterns in the data by grouping similar elements together. However, previous studies on spatial or temporal clustering are incapable of analysing complex patterns in spatio-temporal data. For instance, concurrent spatio-temporal patterns in 2D or 3D datasets. In this study we present two clustering algorithms for complex pattern analysis: (1) the Bregman block average co-clustering algorithm with I-divergence (BBAC_I) which enables the concurrent analysis of spatio-temporal patterns in 2D data matrix, and (2) the Bregman cube average tri-clustering algorithm with I-divergence (BCAT_I) which enables the complete partitional analysis in 3D data cube. Here the use of the two clustering algorithms is illustrated by Dutch daily average temperature dataset from 28 weather stations from 1992 to 2011. For BBAC_I, it is applied to the averaged yearly dataset to identify station-year co-clusters which contain similar temperatures along stations and years, thus revealing patterns along both spatial and temporal dimensions. For BCAT_I, it is applied to the temperature dataset organized in a data cube with one spatial (stations) and two nested temporal dimensions (years and days). By partitioning the whole dataset into clusters of stations and years with similar within-year temperature similarity, BCAT_I explores the spatio-temporal patterns of intra-annual variability in the daily temperature dataset. As such, both BBAC_I and BCAT_I algorithms, combined with suitable geovisualization techniques, allow the exploration of complex spatial and temporal patterns, which contributes to a better understanding of complex patterns in spatio-temporal data.

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Boyd, W. E., C. J. Lentfer, and J. Parr. "Interactions Between Human Activity, Volcanic Eruptions and Vegetation During the Holocene at Garua and Numundo, West New Britain, PNG." Quaternary Research 64, no. 3 (November 2005): 384–98. http://dx.doi.org/10.1016/j.yqres.2005.08.017.

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AbstractThis paper reviews recent fossil phytolith analysis from wet tropical West New Britain (Papua New Guinea). The Holocene vegetation has been influenced by spatially and temporally diverse patterns of both prehistoric human settlement and catastrophic volcanic events. We have hypothesized different landscape responses and recovery pathways to events during the last six millennia. Phytolith sequences on the coastal lowlands, the Willaumez Peninsula, and nearby island of Garua provide details of vegetational change and human interactions at different landscape scales since c. 5900 cal yr B.P. During this period four major volcanic eruptions (c. 5900, 3600, 1700 and 1400 cal yr B.P.) have disrupted the landscape. The evidence provides detailed descriptions of temporal and spatial patterning in the impacts and changes in the vegetation. In particular, vegetation responded differently from one event to another, reflecting both forest recovery from seed bank and shooting, and the influence of prehistoric people on recovering vegetation. Furthermore, after some events landscape recovery was moderately uniform, while after others there was considerable landscape partitioning. Although these differences largely relate to airfall tephra type, distribution and magnitude, the partitioning is more strongly influenced by human activity.

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Wissinger, Scott A. "Comparative population ecology of the dragonflies Libellula lydia and Libellula luctuosa (Odonata: Libellulidae)." Canadian Journal of Zoology 67, no. 4 (April 1, 1989): 931–36. http://dx.doi.org/10.1139/z89-135.

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Temporal and spatial patterns of habitat use, population size structure, and survivorship were compared over three generations of Libellula lydia and Libellula luctuosa in a small pond in Indiana. The two species were univoltine, had similar phenologies, and converged on the same within-pond habitats. There was little evidence for any spatial and (or) temporal habitat partitioning that might be expected between such morphologically and ecologically similar species. Larval populations of each species were highly size structured because oviposition and hatching were extended over 3 months in summer. Intraspecific size differences were greater than those frequently reported to accommodate interspecific coexistence. Thus, intraspecific resource partitioning and cannibalism should have an important effect on population dynamics. Both similar and disparate interspecific size combinations frequently co-occurred in time and space so that competition and predation should simultaneously affect coexistence. Larval mortality was high in late summer and fall, negligible in winter, and high again in spring. Fewer than 10% of either species survived to emerge from the pond. Interodonate predation is a likely source of much of this larval mortality, given that other odonates are among the most abundant large predators in fishless ponds.

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Tomašových, Adam, and Susan M. Kidwell. "Fidelity of variation in species composition and diversity partitioning by death assemblages: time-averaging transfers diversity from beta to alpha levels." Paleobiology 35, no. 1 (2009): 94–118. http://dx.doi.org/10.1666/08024.1.

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Despite extensive paleoecological analyses of spatial and temporal turnover in species composition, the fidelity with which time-averaged death assemblages capture variation in species composition and diversity partitioning of living communities remains unexplored. Do death assemblages vary in composition between sites to a lesser degree than do living assemblages, as would be predicted from time-averaging? And is the higher number of species observed in death relative to living assemblages reduced with increasing spatial scale? We quantify the preservation of spatial and temporal variation in species composition using 11 regional data sets based on samples of living molluscan communities and their co-occurring time-averaged death assemblages. (1) Compositional dissimilarities among living assemblages (LA) within data sets are significantly positively rank-correlated to dissimilarities among counterpart pairs of death assemblages (DA), demonstrating that pairwise dissimilarity within a study area has a good preservation potential in the fossil record. Dissimilarity indices that downplay the abundance of dominant species return the highest live-dead agreement of variation in species composition. (2) The average variation in species composition (average dissimilarity) is consistently smaller in DAs than in LAs (9 of 11 data sets). This damping of variation might arise from DAs generally having a larger sample size, but the reduction by ∼10–20% mostly persists even in size-standardized analyses (4 to 7 of 11 data sets, depending on metric). Beta diversity expressed by the number of compositionally distinct communities is also significantly reduced in death assemblages in size-standardized analyses (by ∼25%). This damping of variation and reduction in beta diversity is in accord with the loss of temporal resolution expected from time-averaging, without invoking taphonomic bias (from differential preservation or postmortem transportation) or sample-size effects. The loss of temporal resolution should directly reduce temporal variation, and assuming time-for-space substitution owing to random walk within one habitat and/or temporal habitat shifting, it also decreases spatial variation in species composition. (3) DAs are more diverse than LAs at the alpha scale, but the difference is reduced at gamma scales because partitioning of alpha and beta components differs significantly between LAs and DAs. This indicates that the effects of time-averaging are reduced with increasing spatial scale. Thus, overall, time-averaged molluscan DAs do capture variation among samples of the living assemblage, but they tend to damp the magnitude of variation, making them a conservative means of inferring change over time or variation among regions in species composition and diversity. Rates of temporal and spatial species turnover documented in the fossil record are thus expected to be depressed relative to the turnover rates that are predicted by models of community dynamics, which assume higher temporal resolution. Finally, the capture by DAs of underlying variation in the LA implies little variation in the net preservation potential of death assemblages across environments, despite the different taphonomic pathways suggested by taphofacies studies.

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Watanabe, Hiroshi. "Improvement of Performance, Stability and Continuity by Modified Size-Consistent Multipartitioning Quantum Mechanical/Molecular Mechanical Method." Molecules 23, no. 8 (July 27, 2018): 1882. http://dx.doi.org/10.3390/molecules23081882.

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For condensed systems, the incorporation of quantum chemical solvent effects into molecular dynamics simulations has been a major concern. To this end, quantum mechanical/molecular mechanical (QM/MM) techniques are popular and powerful options to treat gigantic systems. However, they cannot be directly applied because of temporal and spatial discontinuity problems. To overcome these problems, in a previous study, we proposed a corrective QM/MM method, size-consistent multipartitioning (SCMP) QM/MM and successfully demonstrated that, using SCMP, it is possible to perform stable molecular dynamics simulations by effectively taking into account solvent quantum chemical effects. The SCMP method is characterized by two original features: size-consistency of a QM region among all QM/MM partitioning and partitioning update. However, in our previous study, the performance was not fully elicited compared to the theoretical upper bound and the optimal partitioning update protocol and parameters were not fully verified. To elicit the potential performance, in the present study, we simplified the theoretical framework and modified the partitioning protocol.

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Rodríguez-Pliego, P., H. A. Hernández-Arana, and P. L. Ardisson. "Partitioning spatial and temporal variability of tropical near-shore macrobenthic assemblages affected by natural and anthropogenic disturbances." Marine and Freshwater Research 62, no. 4 (2011): 342. http://dx.doi.org/10.1071/mf10165.

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Coastal zones throughout the world are subject to natural and anthropogenic disturbances that modify the natural assemblages. The present study determined the response of the assemblage of macrobenthic invertebrates to the presence of a pier and natural climatic variations. Two analytical models were considered; one was an asymmetric model that permitted the comparison of the sector closest to the pier (impact) with the average of the sectors located further away (controls); the other was a three-way model that enabled the three sectors within the area to be analysed. With both models, the differences were compared among the sampling periods and the scale at which the variation in the data was greatest. No differences were detected among individual sectors or between the control and impact sectors. However, significant differences were found among the four periods. The zone closest to the pier presented greater temporal variability. This relationship suggests that the pier affecting the assemblage and the impact may be increased by the climatic conditions prevalent in the zone. It is necessary to establish a broader temporal analysis and a more detailed analysis of the structure and composition of the benthic assemblage to elucidate this temporal and spatial variability.

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Sumpton, W., and J. Greenwood. "Pre-and post-flood feeding ecology of four species of juvenile fish from the Logan-Albert Estuarine System, Moreton Bay, Queensland." Marine and Freshwater Research 41, no. 6 (1990): 795. http://dx.doi.org/10.1071/mf9900795.

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The feeding ecology of the four dominant species of juvenile fish found in the Logan-Albert estuarine system are described in terms of the stomach contents of 675 fish examined over a 7-month period. Ontogenetic dietary changes and spatial, temporal and interspecific differences in diet were determined. Johniops vogleri and Polynemus multiradiatus were predominantly planktonic feeders. At an early stage of development, these fish fed mainly on copepods, which were progressively replaced by larger prey such as mysids and Acetes as the fish grew. Arius graeffei and Aseraggodes macleayanus were mainly benthic feeders. Spatial and temporal differences in diet were also evident for each species. These differences probably reflected changes in prey availability resulting from flood-induced changes to the salinity gradient. The potential for competition between Johniops vogleri and Polynemus multiradiatus was reduced by temporal partitioning of food resources as the fish grew.

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Melo, Thaís X., and Elvio S. F. Medeiros. "Spatial Distribution of Zooplankton Diversity across Temporary Pools in a Semiarid Intermittent River." International Journal of Biodiversity 2013 (June 12, 2013): 1–13. http://dx.doi.org/10.1155/2013/946361.

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This study describes the richness and density of zooplankton across temporary pools in an intermittent river of semiarid Brazil and evaluates the partitioning of diversity across different spatial scales during the wet and dry periods. Given the highly patchy nature of these pools it is hypothesized that the diversity is not homogeneously distributed across different spatial scales but concentrated at lower levels. The plankton fauna was composed of 37 species. Of these 28 were Rotifera, 5 were Cladocera, and 4 were Copepoda (nauplii of Copepoda were also recorded). We showed that the zooplankton presents a spatially segregated pattern of species composition across river reaches and that at low spatial scales (among pools or different habitats within pools) the diversity of species is likely to be affected by temporal changes in physical and chemical characteristics. As a consequence of the drying of pool habitats, the spatial heterogeneity within the study river reaches has the potential to increase β diversity during the dry season by creating patchier assemblages. This spatial segregation in community composition and the patterns of partition of the diversity across the spatial scales leads to a higher total diversity in intermittent streams, compared to less variable environments.

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Davis, Naomi E., Ian R. Gordon, and Graeme Coulson. "The influence of evolutionary history and body size on partitioning of habitat resources by mammalian herbivores in south-eastern Australia." Australian Journal of Zoology 65, no. 4 (2017): 226. http://dx.doi.org/10.1071/zo16075.

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Habitat use is the most common dimension along which sympatric species partition resources to reduce competition. We conducted faecal pellet counts at Wilsons Promontory National Park, Victoria, to examine habitat use by an assemblage of mammalian herbivores with disparate evolutionary histories and varying body size: introduced European rabbit (Oryctolagus cuniculus) and hog deer (Axis porcinus), and native eastern grey kangaroo (Macropus giganteus), swamp wallaby (Wallabia bicolor) and common wombat (Vombatus ursinus). Overlap in habitat use was low between four pairs of species, suggesting spatial partitioning of resources to reduce the potential for interspecific competition. More generally, however, overlap in habitat use was high, particularly between native and introduced grazers. These results indicate the potential for competition if resources were limiting and suggest that assemblages of species with independent evolutionary histories have inherently less resource partitioning to facilitate coexistence than assemblages of species with common evolutionary histories. Despite evidence of high overlap in habitat use between native and introduced species at a broad scale, and variation in the competitive ability of species, coexistence was likely facilitated by niche complementarity, including temporal and fine-scale partitioning of spatial resources. There was no relationship between body size and the diversity of habitats used. In contemporary assemblages of native and introduced species, evolutionary history is likely to have a strong influence on resource partitioning.

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Winder, M. "Photosynthetic picoplankton dynamics in Lake Tahoe: temporal and spatial niche partitioning among prokaryotic and eukaryotic cells." Journal of Plankton Research 31, no. 11 (August 28, 2009): 1307–20. http://dx.doi.org/10.1093/plankt/fbp074.

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Stratton, L. C., G. Goldstein, and F. C. Meinzer. "Temporal and spatial partitioning of water resources among eight woody species in a Hawaiian dry forest." Oecologia 124, no. 3 (August 23, 2000): 309–17. http://dx.doi.org/10.1007/s004420000384.

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Klanten, O. Selma, J. Howard Choat, and Lynne van Herwerden. "Extreme genetic diversity and temporal rather than spatial partitioning in a widely distributed coral reef fish." Marine Biology 150, no. 4 (July 11, 2006): 659–70. http://dx.doi.org/10.1007/s00227-006-0372-7.

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Yang, Zhongfang, Xueqi Xia, Yaping Wang, Junfeng Ji, Dacheng Wang, Qingye Hou, and Tao Yu. "Dissolved and particulate partitioning of trace elements and their spatial–temporal distribution in the Changjiang River." Journal of Geochemical Exploration 145 (October 2014): 114–23. http://dx.doi.org/10.1016/j.gexplo.2014.05.013.

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deCastro-Arrazola, Indradatta, Joaquín Hortal, Marco Moretti, and Francisco Sánchez-Piñero. "Spatial and temporal variations of aridity shape dung beetle assemblages towards the Sahara desert." PeerJ 6 (September 20, 2018): e5210. http://dx.doi.org/10.7717/peerj.5210.

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BackgroundAssemblage responses to environmental gradients are key to understand the general principles behind the assembly and functioning of communities. The spatially and temporally uneven distribution of water availability in drylands creates strong aridity gradients. While the effects of spatial variations of aridity are relatively well known, the influence of the highly-unpredictable seasonal and inter-annual precipitations on dryland communities has been seldom addressed.AimsHere, we study the seasonal and inter-annual responses of dung beetle (Coleoptera, Scarabaeidae) communities to the variations of water availability along a semiarid region of the Mediterranean.MethodsWe surveyed a 400 km linear transect along a strong aridity gradient from the Mediterranean coast to the Sahara (Eastern Morocco), during four sampling campaigns: two in the wet season and two in the dry season. We measured species richness, abundance and evenness. Variations in community composition between sites, seasons and years were assessed through beta diversity partitioning of dissimiliarity metrics based on species occurrences and abundances. The effects of climate, soil, vegetation and dung availability were evaluated using Spearman-rank correlations, general linear regressions and partial least-squares generalized linear regressions for community structure, and non-metric multi-dimensional scaling, Permutational Analysis of Variance (PERMANOVA) and distance-based RDA variation partitioning for compositional variations.ResultsDung beetle abundance and species richness showed large seasonal variations, but remained relatively similar between years. Indeed, aridity and its interaction with season and year were the strongest correlates of variations in species richness and composition. Increasing aridity resulted in decreasing species richness and an ordered replacement of species, namely the substitution of the Mediterranean fauna by desert assemblages dominated by saprophagous and generalist species both in space towards the Sahara and in the dry season.DiscussionOur study shows that aridity determines composition in dung beetle communities, filtering species both in space and time. Besides the expected decrease in species richness, such environmental filtering promotes a shift towards generalist and saprophagous species in arid conditions, probably related to changes in resource quality along the transect and through the year. Our results highlight the importance of considering the effects of the highly-unpredictable seasonal and inter-annual variations in precipitation when studying dryland communities.

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Akkawi, Paula, Nacho Villar, Calebe P. Mendes, and Mauro Galetti. "Dominance hierarchy on palm resource partitioning among Neotropical frugivorous mammals." Journal of Mammalogy 101, no. 3 (May 18, 2020): 697–709. http://dx.doi.org/10.1093/jmammal/gyaa052.

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Abstract In tropical forests, the diets of many frugivorous mammals overlap, yet how hyper-diverse assemblages of consumers exploit resources and coexist remains poorly understood. We evaluated competitive interactions among three species of terrestrial frugivorous mammals, the ungulate Tayassu pecari (white-lipped peccary), its close relative Pecari tajacu (collared peccary), and a large rodent (Dasyprocta azarae, agouti), in their exploitation strategies of palm resources of different quality. We conducted the study in a large isolated fragment at the tropical Atlantic Forest of Brazil, where these mammal species show high spatial and temporal overlap. We evaluated if body mass and foraging group size define a hierarchy in exploitation of preferentially richer palm resources. We used camera traps and two-species occupancy models to examine patterns of co-occurrence and variable interaction strength between these consumers and three species of palms. Our analyses supported the hypothesis of partial resource overlap but no competition among frugivores, and a body mass dominance hierarchical exploitation of resources. The larger frugivore (white-lipped peccary) dominated patches of the lipid-rich palm Euterpe edulis, where the smallest frugivore (agouti) was absent. Instead, the smallest frugivore concentrated its foraging in areas with the poorest palm resource, Syagrus oleracea. Collared peccaries preferred areas of high abundance of Syagrus romanzoffiana when the other two mammal species were rarely detected or absent, strongly avoided patches of E. edulis, and showed higher average detection probabilities when agoutis were present. Our study highlights the important role of behavioral plasticity in promoting coexistence and indicates that through context-dependent interactions and hierarchical partitioning of resources, consumers can avoid strong competition, even under conditions of high spatial and temporal overlap and high levels of habitat fragmentation and isolation.

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Lazăr, Anamaria, Ana Maria Benedek, and Ioan Sîrbu. "Small Mammals in Forests of Romania: Habitat Type Use and Additive Diversity Partitioning." Forests 12, no. 8 (August 18, 2021): 1107. http://dx.doi.org/10.3390/f12081107.

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Small mammals are key components of forest ecosystems, playing vital roles for numerous groups of forest organisms: they exert bottom-up and top-down regulatory effects on vertebrate and invertebrate populations, respectively; they are fungus- and seed-dispersers and bioturbators. Therefore, preserving or restoring the diversity of small mammal communities may help maintain the functions of these ecosystems. In Romania, a country with low-intensity forest management and a high percentage of natural forests compared to other European countries, an overview of forest small mammal diversity and habitat type use is lacking, and our study aimed to fill this gap. We also aimed to partition the total small mammal diversity of Romanian forests into the alpha (plot-level), beta, and delta (among forest types) diversities, as well as further partition beta diversity into its spatial (among plots) and temporal (among years) components. We surveyed small mammals by live trapping in eight types of forest across Romania. We found that small mammal abundance was significantly higher in lowland than in mountain forests, but species richness was similar, being associated with the diversity of tree canopy, with the highest values in mixed forests. In contrast, small mammal heterogeneity was related to overall habitat heterogeneity. As predicted, community composition was most distinct in poplar plantations, where forest specialists coexist with open habitat species. Most of the diversity was represented by alpha diversity. Because of strong fluctuations in population density of dominant rodents, the temporal component of beta heterogeneity was larger than the spatial component, but species richness also presented an important temporal turnover. Our results show the importance of the time dimension in the design of the surveys aiming at estimating the diversity of small mammal communities, both at the local and regional scales.

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Chen, Youhua, and Tania Escalante. "Correlates of ecological-niche diversity and extinction risk of amphibians in China under climate change." Australian Systematic Botany 30, no. 6 (2017): 414. http://dx.doi.org/10.1071/sb17001.

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In the present study, we measured spatiotemporal properties of ecological niches of amphibians in China and tested the relative importance of various niche-diversity metrics for explaining the evolutionary distinctiveness-weighted extinction risk (EDGE) of amphibian species. We applied the hierarchical partitioning technique on the phylogenetically independent contrasts of the niche covariates and EDGE of amphibians, for the purpose of removing the influence of evolutionary inertia among species. As a comparison, phylogenetic least-square general regression (PLGS) was also conducted. The results showed that EDGE was high for those amphibian species of China identified as Critically Endangered or Endangered on the IUCN Red List. Niche fragmentation dimension (NFD) and niche position (NP) were the top two predictors across partial correlation analyses, hierarchical variation partitioning, PLGS and multiple regression analyses. Most temporal niche properties were not significantly associated with the EDGE index of amphibians. Variation partitioning analysis showed that the spatial component of niche measures explained the largest proportion of total variation in EDGE (~31%), whereas the temporal component of niche properties explained ~8% of the variation. The significantly negative role of NFD and extinction risk of amphibians in China may be attributed to a reduced rescue effect, habitat geometry, and local extinction in species with large and continuous distributional ranges.

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Li, Yan, Chunlin Huang, William P. Kustas, Hector Nieto, Liang Sun, and Jinliang Hou. "Evapotranspiration Partitioning at Field Scales Using TSEB and Multi-Satellite Data Fusion in The Middle Reaches of Heihe River Basin, Northwest China." Remote Sensing 12, no. 19 (October 3, 2020): 3223. http://dx.doi.org/10.3390/rs12193223.

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Daily evapotranspiration (ET) and its components of evaporation (E) and transpiration (T) at field scale are often required for improving agricultural water management and maintaining ecosystem health, especially in semiarid and arid regions. In this study, multi-year daily ET, E, and T at a spatial resolution of 100 m in the middle reaches of Heihe River Basin were computed based on an ET partitioning method developed by combing remote sensing-based ET model and multi-satellite data fusion methodology. Evaluations using flux tower measurements over irrigated cropland and natural desert sites indicate that this method can provide reliable estimates of surface flux partitioning and daily ET. Modeled daily ET yielded root mean square error (RMSE) values of 0.85 mm for cropland site and 0.84 mm for desert site, respectively. The E and T partitioning capabilities of this proposed method was further assessed by using ratios E/ET and T/ET derived from isotopic technology at the irrigated cropland site. Results show that apart from early in the growing season when the actual E was reduced by plastic film mulching, the modeled E/ET and T/ET agree well with observations in terms of both magnitude and temporal dynamics. The multi-year seasonal patterns of modeled ET, E, and T at field scale from this ET partitioning method shows reasonable seasonal variation and spatial variability, which can be used for monitoring plant water consumption in both agricultural and natural ecosystems.

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Banasiak, Natalia, and Adrian M. Shrader. "Similarities in perceived predation risk prevent temporal partitioning of food by rodents in an African grassland." Journal of Mammalogy 97, no. 2 (December 26, 2015): 483–89. http://dx.doi.org/10.1093/jmammal/gyv192.

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Abstract One way in which animals coexist is through temporal separation of feeding activities. This separation directly reduces interference competition, but potentially not exploitive competition. To reduce exploitive competition, coexisting species tend to utilize different microhabitats and/or achieve different feeding efforts across microhabitats. However, 1 factor that has generally not been considered with regards to its impacts on competition, and thus coexistence, is predation risk. As different predators are active during the day and at night, the location of safe areas across the landscape can vary temporally. If so, then temporally separated prey species would likely forage in different areas thus reducing exploitive competition. However, if predation risk across the landscape is similar for nocturnal and diurnal species, then both could restrict their foraging to the same microhabitats, thus increasing exploitive competition. To explore these alternative possibilities, we manipulated grass height in an African grassland to create microhabitats that varied in predation risk. We then estimated perceived predation risk of both nocturnal and diurnal rodents in these microhabitats by recording giving-up densities (GUDs) in artificial resource patches. We found that despite differences in predators, both nocturnal and diurnal rodents preferred feeding in the same microhabitats, and they achieved similar feeding efforts within these microhabitats. This suggests that despite the prevention of interference competition through temporal partitioning, the spatial similarities in perceived predation risk in relation to cover likely increase exploitive competition between these rodents. However, as both nocturnal and diurnal rodents were present in the study area, it is likely that some other mechanism (e.g., varied diets) allows them to coexist.

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Rodríguez-Pliego, P., H. A. Hernández-Arana, and P. L. Ardisson. "Corrigendum to: Partitioning spatial and temporal variability of tropical near-shore macrobenthic assemblages affected by natural and anthropogenic disturbances." Marine and Freshwater Research 62, no. 7 (2011): 885. http://dx.doi.org/10.1071/mf10165_co.

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Coastal zones throughout the world are subject to natural and anthropogenic disturbances that modify the natural assemblages. The present study determined the response of the assemblage of macrobenthic invertebrates to the presence of a pier and natural climatic variations. Two analytical models were considered; one was an asymmetric model that permitted the comparison of the sector closest to the pier (impact) with the average of the sectors located further away (controls); the other was a three-way model that enabled the three sectors within the area to be analysed. With both models, the differences were compared among the sampling periods and the scale at which the variation in the data was greatest. No differences were detected among individual sectors or between the control and impact sectors. However, significant differences were found among the four periods. The zone closest to the pier presented greater temporal variability. This relationship suggests that the pier affecting the assemblage and the impact may be increased by the climatic conditions prevalent in the zone. It is necessary to establish a broader temporal analysis and a more detailed analysis of the structure and composition of the benthic assemblage to elucidate this temporal and spatial variability.

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Kitchen, Ann M., Eric M. Gese, and Edward R. Schauster. "Resource partitioning between coyotes and swift foxes: space, time, and diet." Canadian Journal of Zoology 77, no. 10 (December 1, 1999): 1645–56. http://dx.doi.org/10.1139/z99-143.

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In its current distribution and abundance, the swift fox (Vulpes velox) has been significantly reduced from its historic range. A possible cause is competition with, and predation by, coyotes (Canis latrans). We investigated the level of spatial, temporal, and dietary resource use overlap between swift foxes and coyotes at the Pinon Canyon Maneuver Site in southeastern Colorado. We captured and radio-tracked 73 foxes and 24 coyotes from April 1997 to August 1998. We collected 10 832 and 5350 locations of foxes and coyotes, respectively. Overall, home-range sizes of foxes and coyotes were 7.6 ± 0.5 (mean ± SE) and 19.8 ± 1.9 km2, respectively. A high degree of interspecies spatial overlap was apparent, with fox home ranges being overlapped by coyote home ranges by as much as 100% and coyote sign (tracks and scats) being evident in all swift fox home ranges. There was no evidence of temporal avoidance of coyotes in fox movement patterns. Coyotes traveled significantly farther than foxes during diurnal hours; foxes spent the majority of diurnal hours in or on top of dens. Coyotes and foxes showed a high index of overlap for dietary resources, although some dietary partitioning was apparent. Swift foxes specialized in small prey, such as insects and rodents, while coyotes used greater proportions of large prey, such as lagomorphs and ungulates. Interference competition was evident, with 48% (12/25) of fox mortalities identified as confirmed or probable coyote-caused deaths. In each case, death occurred outside either the fox's home range or the 85% isopleth of that range, indicating that coyotes are more likely to attack a fox successfully when it is a substantial distance from a den. We propose that swift foxes are able to coexist with coyotes, owing to year-round den use and a degree of dietary partitioning.

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Tew-Kai, Emilie, Victor Quilfen, Marie Cachera, and Martial Boutet. "Dynamic Coastal-Shelf Seascapes to Support Marine Policies Using Operational Coastal Oceanography: The French Example." Journal of Marine Science and Engineering 8, no. 8 (August 5, 2020): 585. http://dx.doi.org/10.3390/jmse8080585.

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In the context of maritime spatial planning and the implementation of spatialized Good Environmental Status indicators in the Marine Strategy Framework Directive (MSFD), the definition of a mosaic composed of coherent and standardised spatial units is necessary. We propose here a characterization of seascapes in time and space within the specific framework of the MSFD in the English Channel and the Bay of Biscay areas. A spatio-temporal classification of coastal-shelf water masses is carried out using twelve essential oceanographic and derived variables from operational coastal oceanography using the HYCOM model. Partitioning is computed using a multivariate hybrid two-step clustering process defining a time series of categorical maps representing hydrographical patch classes. Main patch occurrence is analyzed to understand their spatio-temporal dynamics and their oceanographic characteristics. Finally, patch classes are combined with MSFD marine sub-region delimitations to build seascapes, including ecosystem approach management and marine policy considerations.

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Ferreira, S. C., P. G. da Silva, A. Paladini, and R. A. Di Mare. "Climatic variables drive temporal patterns of α and β diversities of dung beetles." Bulletin of Entomological Research 109, no. 3 (September 4, 2018): 390–97. http://dx.doi.org/10.1017/s0007485318000676.

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AbstractUnderstanding the mechanisms underpinning spatiotemporal diversity patterns of biological communities is a major goal of ecology. We aimed to test two ecological hypotheses: (i) temporal patterns of β-diversity will mostly be driven by nestedness, with a loss of species from summer to winter, and (ii) nestedness values will correlate with climatic variables instead of turnover values, indicating either a loss of species during winter or a gain of species during summer. We sampled dung beetles using standardized sampling protocols along a year in four Atlantic forest sites: two at the northwest and two at the central region of Rio Grande do Sul state, southern Brazil. We partitioned temporal patterns of β-diversity into turnover and nestedness in order to investigate if community changes are driven by species substitution or gain/loss across time. Our results highlighted five main findings: (i) dung beetle composition varied more with sites than site geographic position; (ii) there was almost one and a half ‘true’ dung beetle assemblages regarding the spatial distribution of species weighed by abundance; (iii) we found a positive influence of mean temperature and a negative influence of relative humidity on both species richness and abundance; (iv) both spatial and temporal dissimilarity among sites were dominated by species replacement, while the relative importance of nestedness was higher in temporal than spatial patterns; (v) there was an effect of precipitation and relative humidity on temporal patterns of β-diversity components, but these effects were site-dependent. Contrary to our expectations, the β-diversity component of turnover dominated both spatial and temporal patterns in dung beetle dissimilarity among sites and months. Distinct climatic variables affected differently the α-diversity and β-diversity components of dung beetle assemblages. Partitioning β-diversity into temporal components is a promising approach to unveil patterns of the community dynamics and to produce insights on mechanisms underlying such patterns.

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Chagnon, Jeffrey M., and Peter R. Bannon. "Wave Response during Hydrostatic and Geostrophic Adjustment. Part II: Potential Vorticity Conservation and Energy Partitioning." Journal of the Atmospheric Sciences 62, no. 5 (May 1, 2005): 1330–45. http://dx.doi.org/10.1175/jas3419.1.

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Abstract This second part of a two-part study of the hydrostatic and geostrophic adjustment examines the potential vorticity and energetics of the acoustic waves, buoyancy waves, Lamb waves, and steady state that are generated following the prescribed injection of heat into an isothermal atmosphere at rest. The potential vorticity is only nonzero for the steady class and depends only on the spatial and time-integrated properties of the injection. The waves contain zero net potential vorticity, but undergo a time-dependent vorticity exchange involving latent and relative vorticities. The energy associated with a given injection may be partitioned distinctly among the various wave classes. The characteristics of this partitioning depend on the spatiotemporal detail of the injection, as well as whether the imbalance is generated by injection of heat, mass, or momentum. Spatially, waves of a scale similar to that of the injection are preferentially excited. Temporally, an extended duration injection preferentially filters high-frequency waves. An instantaneous injection, that is, the temporal Green’s function, contains the largest proportions of the high-frequency waves. The proportions of kinetic, available elastic, and available potential energies that are carried by the various waves are functions of the homogeneous system. For example, deep buoyancy waves of small horizontal scale primarily contain equal portions of available potential and vertical kinetic energy. The steady state contains more available potential energy than kinetic energy at small horizontal scale, and vice versa. These qualities of the wave energetics illustrate the mechanisms that characterize the physics of each wave class. The evolution and spectral partitioning of the energetics following localized warmings identical to those in Part I are presented in order to illustrate some of these basic properties of the energetics. For example, a heating lasting longer than a few minutes does not excite acoustic waves. However, Lamb waves of wide horizontal scale can be excited by a heating of several hours. The first buoyancy waves to be filtered by an extended duration heating are those of the deepest and narrowest structure that have a frequency approaching the buoyancy frequency. The energetics of the steady state depends only on the spatial and time-integrated properties of the warming. However, the energetics and transient evolution toward a given steady state depend on the temporal properties of the warming and may differ widely.

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Jachowski, David S., Chris A. Dobony, Laci S. Coleman, William M. Ford, Eric R. Britzke, and Jane L. Rodrigue. "Disease and community structure: white-nose syndrome alters spatial and temporal niche partitioning in sympatric bat species." Diversity and Distributions 20, no. 9 (March 19, 2014): 1002–15. http://dx.doi.org/10.1111/ddi.12192.

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Pech-Canche, Juan M., Claudia E. Moreno, and Gonzalo Halffter. "Additive partitioning of Phyllostomid bat richness at fine and coarse spatial and temporal scales in Yucatan, Mexico." Écoscience 18, no. 1 (March 2011): 42–51. http://dx.doi.org/10.2980/18-1-3392.

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Journal articles on the topic 'Spatial and temporal partitioning'

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