Characterize the major life zones of the ocean, both vertical and horizontal.

The vertical ocean zones are divided into five main layers based on the depth, which affects the amount of sunlight penetration, temperature, and pressure. These layers are: 1. Epipelagic Zone (Surface to 200 meters): Also known as the "sunlight zone", this is the most well-lit and shallowest zone, which supports a large variety of marine life including fish, marine mammals, and photosynthetic organisms like phytoplankton. 2. Mesopelagic Zone (200 to 1,000 meters): Known as the "twilight zone", there is significantly less sunlight here than in the epipelagic zone, and as a result, fewer organisms live here. Bioluminescent animals can be found in this zone, as a means of communication or predation. 3. Bathypelagic Zone (1,000 to 4,000 meters): Also referred to as the "midnight zone", there is no natural sunlight in this zone. The marine organisms here are adapted to live in cold, high-pressure environments, and food sources are mainly limited to detritus falling from above. 4. Abyssopelagic Zone (4,000 to 6,000 meters): In the "abyss", there is total darkness and extremely high pressure. Quite a few organisms can survive in this extreme environment, relying on chemosynthesis and scavenging for sustenance. 5. Hadopelagic Zone (6,000 meters to the ocean floor): This zone is found in the deep trenches of the ocean. The organisms living here are highly specialized for survival in extremely high-pressure and cold environments.

The horizontal ocean zones are determined by their location on Earth, considering factors like climate and proximity to landmasses. There are three main horizontal zones: 1. Neritic Zone: This zone extends from the low tide mark to the edge of the continental shelf (around 200 meters deep). It is characterized by relatively warm shallow waters, with high primary productivity due to sunlight penetration and nutrient input from nearby land. This zone is home to a diverse set of marine ecosystems, including coral reefs, kelp forests, and seagrass beds. 2. Oceanic Zone: Beyond the continental shelf lies the open ocean, which is characterized by lower nutrient concentrations and temperatures. It is further divided into smaller zones based on its latitudinal location: a. Tropical Oceanic Zone: Surrounding the equator, it features warm temperatures and relatively low nutrient concentrations. Within this zone, there are areas of low productivity known as "oceanic deserts". b. Temperate Oceanic Zone: Further away from the equator, this zone experiences seasonal variations in temperature and light. Biological productivity is higher than in the tropical oceanic zone, particularly in areas where nutrient-rich cold waters upwell from the deep ocean. c. Polar Oceanic Zone: Found at the highest latitudes near the Arctic and Antarctic regions, this zone is characterized by cold temperatures, sea ice, and fairly low productivity due to limited light penetration.

The major life zones of the ocean can be characterized vertically and horizontally. The vertical zones focus on the depth of the ocean, considering factors such as light penetration, pressure, and temperature. There are five main vertical zones: epipelagic, mesopelagic, bathypelagic, abyssopelagic, and hadopelagic. The horizontal zones are associated with their location on Earth, taking into account the climate and distance from land. The horizontal zones are the neritic zone and the oceanic zone, which can be further divided into tropical, temperate, and polar oceanic zones.