Solar Lake (Sinai). 1. Physical and chemical limnology1

Abstract

In Solar Lake, a basin at the edge of the sea filled with brine and shielded from the wind, a pycnocline builds up in September due to seepage of seawater to the surface. Solar heating produces a mcsothermic temperature curve with a maximum up to 60.5% at 2.5-3-m depth and decreasing temperatures toward the bottom (40°C at 5 m). The temperature profile together with a supply of nutrients from seepage leads to the development of several bacterial plates and a benthic cyanobacterial bloom. A rapid development of anoxic conditions with up to 39 ppm I-I& a decrease in pH from #top to bottom (S-6.9), redox potential gradients ( +390 to -185 mV), and extremely pronounced light absorption are observed during the period of stratification which lasts from Sepember to July. With increasing solar energy, the seawater supply no longer compensates for the evaporation rate of 3.0 m yr-l and the mesothermy becomes unstable.During a short period of holomixis, lasting from 4-13 weeks, the temperature is 27°C throughout the water column. The sediments of Solar Lake preserve a record of the last 4,600 years from the conditions of a marine lagoon to the development of the limnological cycle presented here.

Distribution and Diversity of Archaea Corresponding to the Limnological Cycle of a Hypersaline Stratified Lake (Solar Lake, Sinai, Egypt)

“…Total mixing of the water column then occurs, and the entire water column is completely oxygenated. Temperature and salinity are constant throughout the water column, and sulfide and methane concentrations are very low during holomixis (6). In the fall, the water column becomes stratified due to the salinity gradient between the residual, highly saline water (18 to 20%) and the overlying, newly introduced seawater (5%).…”

The influence of a fluid-porous interface on solar pond stability

“…Field studies [4,6] show that such an assumption is justified over a certain range of temperature and concentration values which vary with season and local forcing. In this study, parameter values are chosen that reflect those given in Cohen et al for which a linear approximation is appropriate.…”

“…Solar Lake, Israel [4], or can be artificially created to generate heat and electricity, e.g. El Paso solar pond, Texas [19].…”

Modern Stromatolites: A Review

“…The studies of the microenvironments within which the stromatolite growth takes place (e.g. Cohen et al 1977;Krumbein et al 1977) provided further refinement, indicating that complex interactions between organisms and environmental determinants take place at the microscopic as well as macroscopic scale.…”