Use of encounter data to model spatio-temporal distribution patterns of endangered smalltooth sawfish,Pristis pectinata, in the western Atlantic

More than a decade has passed since the publication of the benchmark paper of Costa and Schuster (Costa, J.E. and Schuster, R.L. 1988: The formation and failure of natural dams. Geological Society of America Bulletin 100, 1054-68) on the formation and failure of natural dams. This review takes a critical look at recent trends and developments in international and New Zealand-based research on landslide dams. Temporary or permanent stream blockages by mass movements commonly occur in steep terrain, and gradually receive more attention and awareness with increasing population and land use pressure in upland regions. Different approaches in methodology and their relevance and application potential for engineering and mitigative measures are reviewed and several shortcomings outlined, with a view towards possible future research directions. A high percentage of previous work on landslide dams has been mainly descriptive in character, and has produced a multitude of documented case studies. Recent attempts to redress the balance have included the establishment of global and nationwide databases (inventories) of landslide dams, progress in predictive, quantitative and GIS-based modelling. Furthermore, interpretative approaches towards the reconstruction of former stream blockages and their spatio-temporal distribution patterns have been pursued, which may assist assessments of present and future geomorphic hazards. Both such appraisals as well as management strategies in mountainous regions in general, will have to rely on key data efficiently extracted from a plethora of case examples. Further work includes consideration of temporal and permanent landslide-triggered stream impoundments within Quaternary landscape evolution, quantification of sediment budgets and palaeoenvironmental reconstruction. Overall, there is still a considerable lack of understanding of geomorphic forms and processes involved with landslide-dam formation, stability and failure, part of which is inherent in the often ephemeral nature of stream blockages in coupled hillslope-valley systems.

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Spatio-temporal distribution patterns of two tachinid flies,Epicampocera succincta andCompsilura concinnata parasitizingPieris

Researches on Population Ecology ◽

10.1007/bf02515808 ◽

1989 ◽

Vol 31 (1) ◽

pp. 105-112 ◽

Cited By ~ 2

Author(s):

Keisuke Iwao ◽

Yoshibumi Sato ◽

Naota Ohsaki

Keyword(s):

Temporal Distribution ◽

Distribution Patterns ◽

Spatio Temporal

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Spatio-temporal distribution patterns and conservation of fish assemblages in a Chilean coastal river

Biodiversity and Conservation ◽

10.1007/s10531-007-9171-9 ◽

2007 ◽

Vol 16 (11) ◽

pp. 3179-3191 ◽

Cited By ~ 16

Author(s):

Evelyn Habit ◽

Mark Belk ◽

Pedro Victoriano ◽

Edilia Jaque

Keyword(s):

Fish Assemblages ◽

Temporal Distribution ◽

Distribution Patterns ◽

Spatio Temporal ◽

Coastal River

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Simulating rhizodeposition patterns around growing and exuding root systems

10.1101/2021.02.25.432851 ◽

2021 ◽

Author(s):

Magdalena Landl ◽

Adrian Haupenthal ◽

Daniel Leitner ◽

Eva Kroener ◽

Doris Vetterlein ◽

...

Keyword(s):

Root Architecture ◽

Three Dimensional ◽

Temporal Distribution ◽

Root Systems ◽

Distribution Patterns ◽

Three Dimensions ◽

Root Branching ◽

Architecture Model ◽

Spatio Temporal ◽

Model Approach

1AbstractIn this study, we developed a novel model approach to compute the spatio-temporal distribution patterns of rhizodeposits around growing root systems in three dimensions. This model approach allows us for the first time to study the evolution of rhizodeposition patterns around complex three-dimensional root systems. Root systems were generated using the root architecture model CPlantBox. The concentration of rhizodeposits at a given location in the soil domain was computed analytically. To simulate the spread of rhizodeposits in the soil, we considered rhizodeposit release from the roots, rhizodeposit diffusion into the soil, rhizodeposit sorption to soil particles, and rhizodeposit degradation by microorganisms. To demonstrate the capabilities of our new model approach, we performed simulations for the two example rhizodeposits mucilage and cit-rate and the example root system Vicia faba. The rhizodeposition model was parameterized using values from the literature. Our simulations showed that the rhizosphere soil volume with rhizodeposit concentrations above a defined threshold value (i.e., the rhizodeposit hotspot volume), exhibited a maximum at intermediate root growth rates. Root branching allowed the rhizospheres of individual roots to overlap, resulting in a greater volume of rhizodeposit hotspots. This was particularly important in the case of citrate, where overlap of rhizodeposition zones accounted for more than half of the total rhizodeposit hotspot volumes. Coupling a root architecture model with a rhizodeposition model allowed us to get a better understanding of the influence of root architecture as well as rhizodeposit properties on the evolution of the spatio-temporal distribution patterns of rhizodeposits around growing root systems.

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Opportunistically collected data from aerial surveys reveal spatio-temporal distribution patterns of marine debris in German waters

Environmental Science and Pollution Research ◽

10.1007/s11356-020-10610-9 ◽

2020 ◽

Vol 28 (3) ◽

pp. 2893-2903

Author(s):

Bianca Unger ◽

Helena Herr ◽

Sacha Viquerat ◽

Anita Gilles ◽

Patricia Burkhardt-Holm ◽

...

Keyword(s):

Temporal Distribution ◽

Distribution Patterns ◽

Aerial Survey ◽

Marine Debris ◽

Encounter Rate ◽

The North ◽

Aerial Surveys ◽

Spatio Temporal ◽

German Waters ◽

The Baltic

AbstractMarine debris is known for its ubiquitousness and harmful effects on marine life. This study is the first analysis to provide information on the distribution of floating marine debris in German waters using aerial survey data collected between 2002 and 2016. During regular harbour porpoise monitoring flights, 191,167 km were covered and 26,512 floating debris items recorded (average encounter rate 0.1387 items/km). Debris was encountered more often in the North Sea than in the Baltic Sea (0.16 items/km; 0.08 items/km). The average encounter rate was higher in offshore waters than in coastal areas. Overlaps of marine debris distribution with ‘Special Areas of Conservation’ are a particular reason for concern. Moreover, the spring months (March–May) were identified to be the time of the year with the highest average encounter rates for marine debris. Fishing-related debris was shown to contribute up to 25% of the total number of all observed items. This study shows that opportunistically collected data on marine debris from aerial surveys are valuable for identifying distribution patterns of floating debris without additional survey effort and costs. These data can be used as baseline information to inform management schemes such as the Marine Strategy Framework Directive.

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Spatio-temporal sublittoral macrobenthic distribution and dominant species in Guanabara Bay, Rio de Janeiro, Brazil

Brazilian Journal of Biology ◽

10.1590/1519-6984.230792 ◽

2020 ◽

Author(s):

L. A. Pessoa ◽

P. C. Paiva ◽

R. R. Paranhos ◽

C. A. Echeverría ◽

Marcos A. V. Freitas

Keyword(s):

Annual Cycle ◽

Temporal Distribution ◽

Distribution Patterns ◽

Rainfall Regime ◽

Guanabara Bay ◽

Soft Bottom ◽

Gravity Corer ◽

Structural Variables ◽

High Dominance ◽

Spatio Temporal

Abstract Soft-bottom macrobenthic invertebrates are sensitive to natural or anthropogenic changes in aquatic ecosystems. The distribution patterns of sublittoral macrobenthic species in Guanabara Bay were studied from 2005 to 2007. Samples were collected at ten stations during six surveys throughout the rainfall regime (dry, early and late rainy). Ten replicates were collected at each station by Gravity corer or skin diving. Van Dorn bottles (bottom water) and by Ekman sediment sampler (granulometry) provided material for abiotic data. Stations were grouped into sectors (Entrance, Intermediary and Inner) based on abiotic data and location. The Redundancy Analysis (RDA) and Parsimonious RDA for all years and each annual cycle showed indicator taxa with high dominance in each sector. PERMANOVA indicated a regular seasonality between the surveys for the first annual cycle (p <0.05), and an atypical pattern for the second (p> 0.05), possibly due the low rainfall observed during this period. The mosaic of soft-bottom substrates infers structural variables, and patterns of temporal distribution were basically influenced by parameters those indicating pollution and the SACW (South Atlantic Central Water) intrusion, as well as ecological attributes among species, such as: predation, competition. The Ervilia concentrica and Cypridinidae could be used as indicators for anthropic and natural impacts in the Guanabara Bay for the Entrance sector, while Cyprideis salebrosa and Cyprideis sp. for the Intermediary sector and Heleobia australis for the Inner sector.

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