scholarly journals Spatial and temporal patterns of large-scale droughts in Europe: Model dispersion and performance

2014 ◽  
Vol 41 (2) ◽  
pp. 429-434 ◽  
Author(s):  
Lena M. Tallaksen ◽  
Kerstin Stahl
Keyword(s):  
Large Scale ◽  
Temporal Patterns ◽  
Spatial And Temporal Patterns ◽  
And Performance

Variation in algal assemblages on wave-exposed rocky shores in New South Wales

1998 ◽  
Vol 49 (3) ◽  
pp. 241 ◽  
Author(s):  
A. J. Underwood ◽  
M. G. Chapman
Keyword(s):  
Large Scale ◽  
New South ◽  
New South Wales ◽  
Temporal Patterns ◽  
Explanatory Models ◽  
Small Scale ◽  
Rocky Shores ◽  
Spatial And Temporal Patterns ◽  
South Wales ◽  
Algal Assemblages

Data were collected in New South Wales from replicate sites on five wave-exposed shores separated by hundreds of kilometres at three-monthly intervals for four years, to examine large and small spatial and temporal patterns in low-shore algal assemblages. These data were used to test hypotheses from the models that algal assemblages show large-scale, predictable changes in structure or, alternatively, that variation from time to time is small-scale and differs from shore to shore or site to site on a shore. There was considerable variation at all scales examined — among replicate quadrats within sites, between sites on a shore and among shores. Similarly, assemblages differed from one sampling period to the next and changes in the assemblages over time periods of three months were as great as from year to year. These changes were interactive, with no two sites or shores showing similar temporal patterns. Thus, understanding diversity along a coast-line requires detailed understanding of local processes. Without adequate spatial and temporal replication in sampling designs and without explanatory models, the large and complex variability in intertidal assemblages at different scales cannot be documented and understood.

Spatial and temporal patterns of water loss in heterogeneous landscapes: using plaster models as amphibian analogues

2013 ◽  
Vol 91 (3) ◽  
pp. 135-140 ◽  
Author(s):  
W.E. Peterman ◽  
J.L. Locke ◽  
R.D. Semlitsch
Keyword(s):  
Water Loss ◽  
Activity Patterns ◽  
Physiological Mechanism ◽  
Temporal Patterns ◽  
Spatial And Temporal Patterns ◽  
Evaporative Water ◽  
Heterogeneous Landscape ◽  
Field Deployment ◽  
And Performance ◽  
Plaster Models

Water balance is critical to survival, growth, and performance of many terrestrial organisms because it can influence foraging time, limit dispersal, and curtail courtship activities. Water loss can vary in time and space across the landscape, and can also be modulated by behavior. Amphibians are particularly sensitive to water loss because their skin provides little to no resistance to evaporative water loss. Our study sought to quantify rates of water loss across a heterogeneous landscape using plaster of Paris models as analogues for the Western Slimy Salamander (Plethodon albagula Grobman, 1944). Models were validated within a controlled laboratory setting prior to field deployment, and were shown to approximate rates and magnitudes of water loss observed in living salamanders. In the field, we tested both adult- and juvenile-sized models, and found that juvenile-sized models lost water at a greater rate under all contexts. The rates of water loss measured at night (1.5%/h–4.5%/h) was nearly half of those measured during the day (2%/h–10%/h). Rates of water loss were greatest on ridges with southwestern aspects during the day (5%/h–10%/h) and lowest in ravines with northeast aspects at night (1.50%/h–3.75%/h). The results of spatial and temporal patterns of water loss corroborate field observations of salamander activity patterns and distribution across the landscape, providing a physiological mechanism driving fine-scale habitat use and distribution. Although we tested plaster models as analogues for salamanders, this approach should be generalizable to other amphibian taxa, providing an efficient means of measuring rates of water loss in the field under biologically meaningful contexts.

scholarly journals Spatial and temporal patterns of fish assemblages in mountain streams of the Ren River, southwest China

2021 ◽  
Author(s):  
Fei Liu ◽  
Pengcheng Lin ◽  
Huanzhang Liu ◽  
Jun Wang
Keyword(s):  
Fish Assemblage ◽  
Large Scale ◽  
Southwest China ◽  
Fish Assemblages ◽  
Cold Water ◽  
Temporal Patterns ◽  
Mountain Streams ◽  
Small Scale ◽  
Spatial And Temporal Patterns ◽  
Landscape Factors

The spatial-temporal patterns of fish assemblages in lotic systems can provide useful information in developing effective conservation measures. This study aimed to explore the spatiotemporal changes in fish assemblage and their association with environmental factors in mountain streams of Ren River, southwest China. Filed investigations were conducted at 18 sites during rainy and dry season in 2017. A total of 21 species, belonged to 3 orders, 8 families and 19 genera, were collected. Analysis of similarities (ANOSIM) showed fish assemblages structure varied significantly at the spatial scale, but not at the temporal scale. In low order sites, fish assemblages were mainly dominated by cold water and rheophilic species (e.g. Rhynchocypris oxycephalus, Scaphesthes macrolepis, Metahomaloptera omeiensis and Gnathopogon herzensteini), while those in high order sites were predominated by warm water and eurytopicity or stagnophilic species (e.g. Squalidus argentatus, Hemiculter leucisculus and Zacco platypus). Canonical correspondence analysis (CCA) showed fish assemblages were structured by a combination of large-scale landscape factors (e.g. altitude and C-link) and small-scale habitat features (e.g. channel width, water temperature and depth). Among these factors, landscape factors had the greatest influence on fish assemblage, while local habitat measures played less important roles or just acted in certain season.

scholarly journals Limnology in the Upper Paraná River floodplain: large-scale spatial and temporal patterns, and the influence of reservoirs

2009 ◽  
Vol 69 (2 suppl) ◽  
pp. 717-725 ◽  
Author(s):  
MC. Roberto ◽  
NF. Santana ◽  
SM. Thomaz
Keyword(s):  
Large Scale ◽  
Human Impacts ◽  
Spatial Scales ◽  
Temporal Patterns ◽  
Habitat Diversity ◽  
Paraná River ◽  
River Channels ◽  
Spatial And Temporal Patterns ◽  
Data Set ◽  
Parana River

Knowledge of abiotic limnological factors is important to monitor changes caused by humans, and to explain the structure and dynamics of populations and communities in a variety of inland water ecosystems. In this study, we used a long term data-set (eight years) collected in 10 habitats with different features (river channels, and connected and isolated lakes) to describe the spatial and temporal patterns of some of the principal limnological factors. In general, the degree of connectivity of the lakes, together with the rivers to which the lakes are connected, were important determinants of their limnological characteristics. These differences are expected, because rivers entering the floodplain come from different geological regions and are subject to different human impacts. At large spatial scales, these differences contribute to the increased habitat diversity of the floodplain and thus to its high biodiversity. With regard to temporal variation, Secchi-disk transparency increased, and total phosphorus decreased in the Paraná River main channel during the last 20 years. Although these changes are directly attributed to the several reservoir cascades located upstream, the closing of the Porto Primavera dam in 1998 enhanced this effect. The increase in water transparency explains biotic changes within the floodplain. The lower-phosphorus Paraná River water probably dilutes concentrations of this element in the floodplain waterbodies during major floods, with future consequences for their productivity.

scholarly journals Cnidaria in UK coastal waters: description of spatio-temporal patterns and inter-annual variability

2014 ◽  
Vol 94 (7) ◽  
pp. 1401-1408 ◽  
Author(s):  
Stephen K. Pikesley ◽  
Brendan J. Godley ◽  
Sue Ranger ◽  
Peter B. Richardson ◽  
Matthew J. Witt
Keyword(s):  
Coastal Waters ◽  
Large Scale ◽  
Temporal Patterns ◽  
Spatial And Temporal Patterns ◽  
Annual Variability ◽  
Corrected Data ◽  
Spatio Temporal ◽  
Analyse Data ◽  
The Uk ◽  
Temporal Coverage

Concern has been expressed over future biogeographical expansion and habitat capitalization by species of the phylum Cnidaria, as this may have negative implications on human activities and ecosystems. There is, however, a paucity of knowledge and understanding of jellyfish ecology, in particular species distribution and seasonality. Recent studies in the UK have principally focused on the Celtic, Irish and North Seas, but all in isolation. In this study we analyse data from a publicly-driven sightings scheme across UK coastal waters (2003–2011; 9 years), with the aim of increasing knowledge on spatial and temporal patterns and trends. We describe inter-annual variability, seasonality and patterns of spatial distribution, and compare these with existing historic literature. Although incidentally-collected data lack quantification of effort, we suggest that with appropriate data management and interpretation, publicly-driven, citizen-science-based, recording schemes can provide for large-scale (spatial and temporal) coverage that would otherwise be logistically and financially unattainable. These schemes may also contribute to baseline data from which future changes in patterns or trends might be identified. We further suggest that findings from such schemes may be strengthened by the inclusion of some element of effort-corrected data collection.

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