Temporal and spatial variability in elemental composition of otoliths: implications for determining stock identity and connectivity of populations

2002 ◽  
Vol 59 (4) ◽  
pp. 669-679 ◽  
Author(s):  
Bronwyn M Gillanders
Keyword(s):  
Temporal Variation ◽  
Elemental Composition ◽  
Juvenile Fish ◽  
Spatial And Temporal Variation ◽  
Otolith Chemistry ◽  
Temporal And Spatial Variability ◽  
Spatial Differences ◽  
Elemental Fingerprint ◽  
Temporal And Spatial ◽  
Over Time

Interannual variability in elemental composition of otoliths may confound spatial interpretations. The elemental fingerprints of otoliths of juvenile fish were determined for fish collected from 12 to 15 estuaries in each of three consecutive recruitment years to determine temporal variation in otolith chemistry for each estuary. It was also examined whether there is overlap in elemental fingerprints of fish collected in different years and from different estuaries that may confound subsequent spatial comparisons. Significant differences in otolith chemistry were found among years for individual elements (lithium, manganese, strontium, and barium) and for multi-element fingerprints. Some estuaries showed large variation in multi-element fingerprints among years, whereas others showed little variation among years. There was some overlap of elemental fingerprints of different estuaries, but these were not always for fish collected in the same year. The significant spatial and temporal variation in elemental fingerprints meant that it was possible to confound spatial differences with temporal differences. Therefore, if the natal estuary of the adults is to be determined, a library of elemental fingerprints needs to be built up over time for each estuary rather than a single year-class of juveniles being used as the elemental fingerprint for a number of year-classes of adults.

Spatial and temporal variation in littoral-zone benthic invertebrates from three south-central Ontario lakes

1995 ◽  
Vol 52 (7) ◽  
pp. 1406-1420 ◽  
Author(s):  
R. A. Reid ◽  
K. M. Somers ◽  
S. M. David
Keyword(s):  
Temporal Variation ◽  
Benthic Invertebrates ◽  
Seasonal Changes ◽  
Littoral Zone ◽  
Spatial And Temporal Variation ◽  
South Central ◽  
Temporal Factors ◽  
Follow Up Studies ◽  
Spatial Differences

Surveys of benthic invertebrates have revealed patterns attributed to the impacts of acid deposition. Unfortunately, these patterns may be confounded by temporal variation that will affect follow-up studies of the recovery of these communities. Here, we assess spatial and temporal variation in time-limited, kick-and-sweep collections of littoral-zone benthos. Spatial variation comprised five sites representing the predominant nearshore substrates in each of three lakes. Temporal variation spanned a different scale in each lake with five sites sampled: (i) twice on the same day, (ii) once a week for 3 weeks, and (iii) four times through the ice-free season. Variation was quantified using a model II analysis of variance. Spatial differences predominated in same-day samples (60.4% of the variation on average) and those collected over a 3-week period (46.1%). In contrast, samples collected over the ice-free season revealed that spatial and temporal factors accounted for 9.4 and 25.6% of the variation. We conclude that our collections of littoral macrobenthos are highly repeatable if sampling is restricted to short periods (e.g., 3 weeks). Surveys spanning longer periods may incorporate considerable temporal variation from seasonal changes in abundance.

Spatial and temporal variation in assemblages of Lutjanidae, Lethrinidae and associated fish species among mid-continental shelf reefs in the central Great Barrier Reef

2001 ◽  
Vol 52 (6) ◽  
pp. 843 ◽  
Author(s):  
Stephen J. Newman ◽  
David McB. Williams
Keyword(s):  
Continental Shelf ◽  
Temporal Variation ◽  
Fish Assemblages ◽  
Spatial And Temporal Variation ◽  
Shallow Trap ◽  
Fish Traps ◽  
Lutjanus Carponotatus ◽  
Plectropomus Leopardus ◽  
Trap Catches ◽  
Over Time

Visual censuses were used to survey shallow-water assemblages of the Lutjanidae and Lethrinidae among three mid-continental shelf reefs, and fish traps were used to survey deeper water assemblages below diveable depths. Significant differences were found in visual censuses of the Lutjanidae and Lethrinidae among reefs. Trap catches of the Lutjanidae and Lethrinidae varied more between depths and diel sampling periods than among reefs or over time. Lutjanus carponotatus, L. fulviflamma and Lethrinus miniatus were more abundant in shallow trap sets, whereas Lutjanus adetii, L. russelli, L. sebae, L. vitta, Gymnocranius audleyi, Lethrinus sp.2 and Abalistes stellaris were more abundant in deeper sets. Additionally, Lutjanus adetii, L. fulviflamma, L. quinquelineatus, L. russelli, L. sebae, L. vitta and Lethrinus miniatus were more abundant at night, whereas Lethrinus sp. 2, Abalistes stellarisand Plectropomus leopardus were more abundant during the day. The absence of significant temporal variation in the observed spatial patterns both among reefs and between depths indicates that these patterns may persist through time. The use of both visual censuses and fish traps to assess reef fish assemblages may provide an objective way of repeatedly censusing reefs for monitoring purposes, especially where differences among reefs and regions are important.

scholarly journals Spatial and Temporal Variation in an Apple Orchard

HortScience ◽  
2019 ◽  
Vol 54 (12) ◽  
pp. 2182-2187
Author(s):  
Babak Talebpour ◽  
Maksut Barış Eminoğlu ◽  
Uğur Yegül ◽  
Ufuk Türker
Keyword(s):  
Temporal Variation ◽  
Precision Agriculture ◽  
Temporal Stability ◽  
Apple Orchard ◽  
The Other ◽  
Spatial And Temporal Variation ◽  
Spatial And Temporal Variability ◽  
Research Station ◽  
Temporal Variance ◽  
Over Time

One important goal of precision horticulture (PH), as well as precision agriculture (PA), is to measure and manage spatial and temporal variation in orchards. In this study, temporal and spatial analysis of yields were carried out over 2 years for a 0.5-ha apple orchard (at the Haymana Research Station of Ankara University, Turkey, from 2017 to 2018) to determine the variability of yields over time and included seven apple varieties: ‘Royal Gala’, ‘Red Chief’, ‘Braeburn’, ‘Mondial Gala’, ‘Jonagold’, ‘Fuji’, and ‘Mitch Gala’. To achieve this, yield data for two different years were analyzed for mean yield, temporal variance, and cv in terms of spatial and temporal stability, and their yield maps were produced. The results showed that ‘Jonagold’, ‘Braeburn’, and ‘Red Chief’ varieties yielded less than the average yield, whereas the other varieties produced average yields when the yield from 2 years was taken into account. Calculation of the values for determining temporal stability over time resulted in all existing varieties being identified as stable over time. For example, the ‘Jonagold’ and ‘Red Chief’ varieties showed 100% stability in terms of temporal variance. Results also showed that the ‘Gala’ varieties were stable for 2 years and produced high yields, whereas the other varieties were specified as stable and low yielding when spatial and temporal variability was considered in combination.

scholarly journals Hot spot detection and spatio-temporal dynamics of dengue in Queensland, Australia

2014 ◽  
Vol XL-8 ◽  
pp. 197-204 ◽  
Author(s):  
S. Naish ◽  
S. Tong
Keyword(s):  
Temporal Variation ◽  
Temporal Dynamics ◽  
Hot Spot ◽  
Seasonal Pattern ◽  
Temporal Distribution ◽  
Health Concern ◽  
Spatial And Temporal Variation ◽  
Dengue Case ◽  
Spatio Temporal ◽  
Over Time

Dengue has been a major public health concern in Australia since it re-emerged in Queensland in 1992–1993. This study explored spatio-temporal distribution and clustering of locally-acquired dengue cases in Queensland State, Australia and identified target areas for effective interventions. A computerised locally-acquired dengue case dataset was collected from Queensland Health for Queensland from 1993 to 2012. Descriptive spatial and temporal analyses were conducted using geographic information system tools and geostatistical techniques. Dengue hot spots were detected using SatScan method. Descriptive spatial analysis showed that a total of 2,398 locally-acquired dengue cases were recorded in central and northern regions of tropical Queensland. A seasonal pattern was observed with most of the cases occurring in autumn. Spatial and temporal variation of dengue cases was observed in the geographic areas affected by dengue over time. Tropical areas are potential high-risk areas for mosquito-borne diseases such as dengue. This study demonstrated that the locally-acquired dengue cases have exhibited a spatial and temporal variation over the past twenty years in tropical Queensland, Australia. There is a clear evidence for the existence of statistically significant clusters of dengue and these clusters varied over time. These findings enabled us to detect and target dengue clusters suggesting that the use of geospatial information can assist the health authority in planning dengue control activities and it would allow for better design and implementation of dengue management programs.

Temporal and spatial variability in seedling dynamics: a cross-site comparison in four lowland tropical forests

2008 ◽  
Vol 24 (1) ◽  
pp. 9-18 ◽  
Author(s):  
Margaret R. Metz ◽  
Liza S. Comita ◽  
Yu-Yun Chen ◽  
Natalia Norden ◽  
Richard Condit ◽  
...  
Keyword(s):  
Temporal Variation ◽  
Tropical Forests ◽  
Spatial And Temporal Variation ◽  
Monitoring Methods ◽  
Bayesian Hierarchical ◽  
Seedling Demography ◽  
Temporal And Spatial Variability ◽  
Seedling Dynamics ◽  
Lowland Forests

Abstract:Spatial and temporal variation in seedling dynamics was assessed using records of community-wide seedling demography collected with identical monitoring methods at four tropical lowland forests in Panama, Malaysia, Ecuador and French Guiana for periods of between 3 and 10 y. At each site, the fates of between 8617 and 391 777 seedlings were followed through annual censuses of the 370–1008 1-m2 seedling plots. Within-site spatial and inter-annual variation in density, recruitment, growth and mortality was compared with among-site variability using Bayesian hierarchical modelling to determine the generality of each site's patterns and potential for meaningful comparisons among sites. The Malaysian forest, which experiences community-wide masting, was the most variable in both seedling density and recruitment. However, density varied year-to-year at all sites (CVamong years at site = 8–43%), driven largely by high variability in recruitment rates (CV = 40–117%). At all sites, recruitment was more variable than mortality (CV = 5–64%) or growth (CV = 12–51%). Increases in mortality rates lagged 1 y behind large recruitment events. Within-site spatial variation and inter-annual differences were greater than differences among site averages in all rates, emphasizing the value of long-term comparative studies when generalizing how spatial and temporal variation drive patterns of recruitment in tropical forests.

Analysis of Time-Spatial Characteristics of Summer Precipition in Chongqing Region during 45 a

2012 ◽  
Vol 599 ◽  
pp. 690-696
Author(s):  
Fan Hua Min ◽  
Bai Cheng Xia ◽  
De Liu ◽  
Yu Han
Keyword(s):  
Annual Variation ◽  
Summer Precipitation ◽  
Morlet Wavelet ◽  
Precipitation Data ◽  
Common Features ◽  
Maximum Value ◽  
Temporal And Spatial Variability ◽  
Spatial Differences ◽  
The Common ◽  
Temporal And Spatial

Using 1966~2010 year Jun.~Aug. precipitation data over 34 stations of Chongqing region, the temporal and spatial variability features were studied by applying the methods of EOF, REOF, Morlet wavelet analysis. The results indicate that the summer precipitation spatial differences are great. The summer precipitation distribution exhibits the common features as well as the spatial differences, which can be classified into four types as Northeast, Northwest, Southeast and Southwest Chongqing. The inter-annual variation characteristic in the four types is not correspondent. Northeast and Southwest ones are like a parabolic curve which have a maximum value and Southwest and Northwest ones exist upward tendency. The periods of the four types are not unanimous.

scholarly journals Spatial distribution and increase of microplastics over time in sediments of Buenaventura Bay, Colombian Pacific

2021 ◽  
Vol 50 (1) ◽  
pp. 27-42
Author(s):  
Daniela Vásquez ◽  
Andres Molina ◽  
Guillermo Duque
Keyword(s):  
Spatial Distribution ◽  
Adverse Effects ◽  
Human Populations ◽  
Sediment Samples ◽  
Marine Communities ◽  
Density Separation ◽  
Spatial Differences ◽  
Marine Influence ◽  
Temporal And Spatial ◽  
Over Time

The increase in production, consumption and inadequate disposition of plastics has generated an accumulation of these elements in marine ecosystems, which have become important microplastics sinks (< 5 mm). The objective of this research was to determine the temporal and spatial differences in the density, distribution, and type of microplastics in the sediments of Buenaventura Bay. For this purpose, sediment samples were collected in the internal estuary (close to the rivers) and in the external estuary (with a greater marine influence). Samples were obtained in the dry, transition, and rainy season for the years 2015 and 2019. Microplastics were extracted by density separation method, each particle was classified and measured by optical microscopy. Density ranged from 11 to 1,354 particles/kg, with averages of 194.9 ± 51.3 and 359.6 ± 88.0 particles/kg for the years 2015 and 2019, respectively, reporting an increase of 84.4 %. The internal estuary presented a higher density in both years and the fibers constituted the most common form of microplastic particles, with 63.7 % for 2015 and 56.03 % for 2019. The presence and increasing accumulation of microplastics generates risks and adverse effects for the marine communities; additionally it coul compromise the food safety for coastal human populations.

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