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Benthic Zone

Freshwater Lakes (Lentic)

Still or slow-moving freshwater bodies - from puddles to Lake Baikal - each with characteristic thermal stratification, oxygen dynamics, and fish community structure.

Depth: 0-1,700m Light: Sunlight

📖 Overview

Lentic (still) freshwater systems range from ephemeral rain pools to Lake Baikal. Thermal stratification in deep lakes creates the epilimnion (warm surface), thermocline (transition), and hypolimnion (cold deep) - each with distinct fish communities. Ice cover in temperate regions creates winterkill risk. Ancient lakes (Baikal, Tanganyika, Malawi, Ohrid) are evolutionary hotspots.

🌿 Ecology

Phytoplankton-zooplankton-fish food web. Thermal stratification creates seasonal habitats. Turnover events (fall, spring) redistribute oxygen.