Lost in the dark: estimation of the akinete pool for the recruitment of Nostocales populations (cyanobacteria) in a temperate deep lake

2017 ◽  
Vol 39 (3) ◽  
pp. 392-403 ◽  
Author(s):  
Jessica Ramm ◽  
Jacqueline Rücker ◽  
Matthias Knie ◽  
Brigitte Nixdorf
Keyword(s):  
Deep Lake

Between the Devil and the Deep Lake Constance

2018 ◽  
Author(s):  
Alexander O'Hara
Keyword(s):  
Lake Constance ◽  
Deep Lake ◽  
The Devil

In his Vita Columbani Jonas of Bobbio provides the earliest instance of an interpretatio Christiana of the Alamannic god Woden, unequivocally identifying him with the devil. The significance of Jonas’s story about Columbanus and the pagan Alamanni does not lie in its preservation of any authentic details of Alamannic ritual, but rather in the fact that this is the oldest instance of interpretatio Christiana in the Germanic-speaking world.

scholarly journals Topset-to-forest rollover trajectories as reliable predictors of sediment-volume partitioning into deep-lake areas

2021 ◽  
Author(s):  
Xian-Zheng Zhao ◽  
Cheng-Lin Gong ◽  
Li-Hong Zhou ◽  
Dong-Wei Li ◽  
Xiu-Gang Pu ◽  
...  
Keyword(s):  
Bohai Bay ◽  
Deep Lake ◽  
Bohai Bay Basin ◽  
Widespread Occurrence ◽  
Sediment Volume ◽  
Terrestrial Sediments ◽  
Qikou Sag ◽  
Sand Budget ◽  
Stacking Patterns

AbstractTopset-to-forest rollover trajectories and their relation to sediment- and sand-budget partitioning into deep-lake areas are far from being well understood, as compared with their marine counterparts of shelf edges. Two quantitatively distinctive topset-to-forest rollover trajectories and clinothem-stacking patterns were recognized in the Oligocene Qikou Sag of the Bohai Bay Basin and are quantified in terms of trajectory angles (Tse), topset thickness (Tt), forest thickness (Tf), bottomset thickness (Tb), and clinothem-set relief (Rc). Rising topset-to-forest trajectories have positive Tse of 0.15°–0.51° (averaging 0.35°). Ranges in Tt, Tf, Tb, and Rc of their associated progradational and aggradational clinothem sets are, respectively, 32.4–58.7 m (averaging 42.7 m), 76.9–176.2 m (averaging 148.3 m), 0 m, and 167.8–320.8 m (averaging 272.9 m). Falling topset-to-forest rollover trajectories, in contrast, have negative Tse of − 0.12° to − 0.02° (averaging − 0.06°). Ranges in Tt, Tf, Tb, and Rc of their associated progradational and downstepping clinothem sets are, respectively, 0 m, 266.0–395.7 m (averaging 333.4 m), 441.1–542.5 m (averaging 464.1), and 874.9–922.6 m (averaging 892.5 m). These two topset-to-forest rollover trajectories and clinothem-stacking patterns are closely linked to two distinctive patterns of sediment- and sand-volume partitioning into deep-lake areas, which are quantified in terms of Tt, Tb, and differential sediment aggradation of topset segments and forest-to-bottomset compartments (As/Ad). Rising topset-to-forest rollover trajectories and associated progradational and aggradational clinothem sets are characterized by aggradational topsets (reported as Tt of 32.4–58.7 m), a lack of time-equivalent bottomsets, and As/Ad of 0.22–0.87 (averaging 0.33), and are fronted by mud-dominated depositional deposits, with sporadic occurrence of thinner and regionally localized forest sands. They are, therefore, inefficient at delivering terrestrial sediments or sands into deep-lake settings. Falling topset-to-forest rollover trajectories and associated progradational and downstepping clinothem sets, in contrast, are characterized by toplap, erosional terminations but aggradational bottomsets (reported as Tb of 266.0–473.4 m), and As/Ad of 0, and are fronted by sand-rich depositional deposits, with widespread occurrence of thicker and regionally extensive time-equivalent deep-lake bottomset sands. They are, thus, efficient at delivering terrestrial sediments or sands into deep-lake settings. Topset-to-forest rollover trajectories and associated clinothem-stacking patterns are thus reliable predictors of sediment- and sand-volume partitioning into deep-lake areas, assisting greatly in developing a more dynamic stratigraphy.

Study on Sedimentary Characteristics of Zhang Jia Po Group, Gushi Hollow of Weihe Basin

2013 ◽  
Vol 772 ◽  
pp. 844-848
Author(s):  
Lin Zhang ◽  
Jian Chao Liu ◽  
Xing Yun Wang ◽  
Jian Feng Bai
Keyword(s):  
Shallow Lake ◽  
Facies Analysis ◽  
Sedimentary Facies ◽  
Sedimentary Structure ◽  
Deep Lake ◽  
Sedimentary Characteristics ◽  
Rock Types ◽  
Single Well ◽  
Weihe Basin ◽  
Sedimentary Microfacies

Through the paleontology, lithology combination data,For Weihe basin Gushi hollow Tertiary the Zhangjiapo group unified hierarchical total divided into seven sections. According to coring, logging data to study the rock types and sedimentary structure,Summed up the logging of various sedimentary microfacies facies, clear in the study area is a shallow lake - a deeper lake - deep lake - deeper lake - shallow lake cyclic sedimentation.For single well facies analysis of typical wells in the region, the establishment of even well profile, determine the small layer of sedimentary facies the planar distribution concluded sedimentary facies model.

Modelling multi-species algal bloom in a lake and inter-algal competitions

2009 ◽  
Vol 60 (10) ◽  
pp. 2599-2611 ◽  
Author(s):  
Monzur Alam Imteaz ◽  
Abdallah Shanableh ◽  
Takashi Asaeda
Keyword(s):  
Water Quality ◽  
Algal Bloom ◽  
Ecological Model ◽  
Algal Species ◽  
Dynamic Responses ◽  
Bubble Plume ◽  
Deep Lake ◽  
Blue Green Algae ◽  
Artificial Mixing ◽  
Using Data

A numerical model was developed to simulate water quality and algal species composition in a deep lake. As artificial destratification is widely used in the lakes, a destratification (bubble plume) model was incorporated with the ecological model to simulate the dynamic responses of different species under artificial mixing. The ecological model predicts concentrations of PO4-P, NH4-N, NO3-N, DO and pH throughout the water column, all of which have a significant influence on the growth of different algal species. The model has been calibrated using data from Uokiri Lake (Japan) for two different species (Diatom and Cyanobacteria) with and without artificial mixing. The calibrated model was used to simulate different conditions of artificial mixing within the lake over a period of five months. The simulation results show that artificial mixing favors non-motile heavier species, such as Diatom, while preventing the growth of Blue-green algae. It is also demonstrated that intermittent operation of the artificial mixing is better for water quality amelioration than continuous operation.

scholarly journals Energy analysis using carrier HAP program and Deep Lake Water Cooling (DLWC) feasibility analysis for Ryerson University

2021 ◽  
Author(s):  
Md. Ziaur Rahman
Keyword(s):  
Energy Consumption ◽  
Total Energy ◽  
Lake Water ◽  
Building Energy ◽  
Energy Simulation ◽  
Base Case ◽  
Water Cooling ◽  
Ghg Emission ◽  
Deep Lake ◽  
Total Energy Consumption

The objective of this project is to determine the total annual energy summary in terms of cost and Greenhouse Gas (GHG) emission of 16 buildings at Ryerson University (RU). In addition, the Deep Lake Water Cooling (DLWC) feasibility analysis of RU is another objective of this project in terms of total energy consumption and amount of gas emission reduction. The total audit area of RU was 86% of the total campus area. Building energy simulation program, Carrier HAP (Hourly Analysis Program), has been used to make an integrated evaluation of building energy consumption. An energy simulation involves hour-by-hour calculations for all 8,760 hours in a year. In this project, an energy audit was conducted for the 16 existing buildings to establish the base case model, "Ryerson University", to determine its annual energy consumption across all usage. There are two sources of energy used at RU. Electricity uses for lighting, plug load, miscellaneous and cooling, and remote steam is used for cooling and heating. For the base case model, total energy consumption was 251 TJ. To reduce the total energy consumption of the base case model, HVAC systems were investigated to analyze their energy-based performance and impact on the GHG emission. There is no Heat Recovery Ventilation (HRV) system coming from the investigation of HVAC system. The sensitivity analysis was conducted using HRV system with air system. By using HRV system with air system, total of 5.6% energy would be saved for cooling and 76% energy would be saved for heating of RU. The energy intensity was determined to be 1.04 GJ/m² only for 16 buildings of RU and comparatively it is lower than other universities in Canada which have a range of 1.64 GJ/m² to 2.26 GJ/m². In the DLWC system, cool lake water at 4°C was used for building air conditioning. To reduce the cooling energy costs, DLWC system was considered as an alternative chilled water source. The Rogers Business Building (RBB) already has DLWC system. For DLWC system, chilled water was served by Enwave to the RBB. According to base case analysis of the RBB with conventional chillers, the electricity consumption was 924594 kWh for RBB due to chillers. With the implementation of DLWC system for the rest of the 15 buildings, total energy saving due to cooling would be 89.2% and GHG emission reduction would be 89% for CO₂, 70% for NOx and 70.4% for SOx due to elimination of chillers.

scholarly journals Verification of seiching processes in a large and deep lake (Trichonis, Greece)

2000 ◽  
Vol 1 (1) ◽  
pp. 79 ◽  
Author(s):  
I. ZACHARIAS
Keyword(s):  
Time Series ◽  
Spectral Analysis ◽  
Phase Shift ◽  
Finite Difference ◽  
Phase Difference ◽  
Experimental Verification ◽  
Computational Analysis ◽  
Power Spectral Analysis ◽  
Deep Lake ◽  
Power Spectral

A computational analysis of the periods and structure of surface seiches of Lake Trichonis in Greece and its experimental verification from three simultaneous water gauge recordings, mounted along the shores in Myrtia, Panetolio and Trichonio is given. The first five theoretical modes are calculated with a finite difference code of tidal equations, which yield the eigenperiodes, co-range and co-tidal lines that are graphically displayed and discussed in detail.Experimental verifications are from recordings taken during spring. Visual observations of the record permit identification of the five lowest order modes, including inter station phase shift. Power spectral analysis of two time series and interstation phase difference and coherence spectra allow the identification of the same five modes. Agreement between the theoretically predicted and the experimentally determined periods was excellent for most of the calculated modes.

scholarly journals Oxycline oscillations induced by internal waves in deep Lake Iseo

2018 ◽  
Author(s):  
Giulia Valerio ◽  
Marco Pilotti ◽  
Maximilian Peter Lau ◽  
Michael Hupfer
Keyword(s):  
Internal Waves ◽  
Water Layer ◽  
Sediment Surface ◽  
Chemical Gradient ◽  
Deep Lakes ◽  
Deep Lake ◽  
Deep Waters ◽  
Basin Scale ◽  
First Time

Abstract. Lake Iseo is undergoing a dramatic de-oxygenation of the hypolimnion, representing an emblematic example among the deep lakes of the prealpine area that are, to a different extent, suffering from reduced deep water mixing. In the anoxic deep waters, the release and accumulation of reduced substances and phosphorus from the sediments is a major concern. Since the hydrodynamics of this lake was shown to be dominated by internal waves, in this study we investigate for the first time the role of these oscillatory motions on the vertical fluctuations of the oxycline, currently situated at a depth of around 95 m, where a permanent chemocline inhibits deep mixing by convection. Temperature and dissolved oxygen data measured at moored stations show large and periodic oscillations of the oxycline, with amplitude up to 20 m and periods ranging from 1 to 4 days. A deep dynamics characterized by larger amplitudes at lower frequencies is shown to be favoured by the excitation of second vertical modes in strongly thermally stratified periods and of first vertical modes in weakly thermally stratified periods, when the deep chemical gradient can support baroclinicity anyhow. These basin-scale internal waves cause in the water layer between 85 and 105 m depth a fluctuation of the oxygen concentration between 0 and 3 mg L−1 that, due to the bathymetry of the lake, changes the redox condition at the sediment surface. This forcing, involving about 3 % of the lake's sediment area, can have major implications for the biogeochemical processes at the sediment water interface and for the internal matter cycle.

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