Hand out : ECOSYSTEM - Ms. Airill L. Mercurio

Ecosystem – interacting biotic and abiotic factors

1) Components : Autotrophs - producers Heterotrophs – consumers and decomposers

Two major classifications: Terrestrial and Aquatic

Aquatic – divided into freshwater and marine water

FRESHWATER

Limnology – study of freshwater divided into : a) Lotic – running waters, b ) Lentic – standing waters

Types of lakes based in nourishment:

a) Eutrophic lakes – with high nourishment, characterized by shallow warm turbid waterb) Oligotrophic lakes – with low nourishment, characterized by deep, cold clear waterc) Dystrophic lakes – usually water is brownish in color due to high deposition of

sediments

Classification of organisms present in aquatic ecosystem:

Benthos – resting or living at the bottomPeriphyton – attached or clinging on stems of leaves of rooted plantsPlankton – floating , dependent on currentNektons – swimming can navigate at willNeuston – resting or swimming on the surface

Zones of freshwater

Lentic

a) Littoral zone – shallow water region with light penetration up to botton, near to the shoreb) Limnetic zone – open water zonec) Profundal zone – bottom deep water area beyond the depth of effective light penetration

Lotic

a) rapid – shallow water where water current is greatb) pool – deeper water where velocity of current is reduced

Types of plants : Emergent – rooted plants with foliage above the water surface Submergent – rooted plants with foliage underneath the water surface

Marine Ecosystems Study of marine habitats – Oceanography

Divisions of the Ocean

1. Pelagic division- includes the open sea:Divided into:

A) Neritic / Coastal - shallow water above the continental shelf Subdivided into 3 zones: Supratidal –above high tide mark Intertidal – between the high tide and low tide mark Subtidal – below the low tide mark

Productive Ecosystems:

a) rocky shoresb) sandy beachesc) coral reefs – produced from corals – tiny animals known as “polyps”

- serve as habitat and barrier against huge waves preventing soil erosiond) mangroves – woody trees with roots submerged in water

- act as habitat for waterfowl, protect against waves and nursing ground for small fishes and other vertebrates

e) Estuary – where freshwater meets the salt water

B) Oceanic province – region of open sea beyond the continental shelf- divided into 4 zonesa) euphotic zone – known as the photosynthetic zone ( up to 120 m

depth)b) bathyal zone – twilight zone ( upto 3,000 m depth)c) abyssal zone – dark zone ( up to 4,000 m depth)d) hadal – beyond 4,000 depth

C) Benthic zone - include the depths of the sea

Divided into 3 zonesa) continental shelf in the sublittoral shelf, the floor of

neritic provinceb) Continental slope in the bathyal zone – a sudden drop of

the ocean floor from the continental shelf up to abyssal plain

c) Abyssal plain in the abyssal zone, the ocean floor of the abyssal zone

Ecological Pyramids

a) Pyramid of biomass – pertains to the number of organisms multiplied by their dry weight Biomass – refers to total dry weight of all organisms

- pyramid of biomass in aquatic is inverted

b) Pyramid of energy Energy – the capacity to do work 2 Laws of Thermodynamics:

a) Law of Conservation of energy – energy is neither created nor destroyed b) Law of Entropy or transformation of energy – energy is transformed from a useful to a less useful form of energy which is heat

- only 10% of energy is transferred from one trophic level to another, 90% is released to the environment in the form of heat

- pyramid of energy is always in upright position in any ecosystems

c) Pyramid of numbers - shows the number of organisms in each trophic level

Biomes – are terrestrial climax community with wide geographic location - named for their predominant vegetation

Factors affecting biomes:

a) temperatureb) amount of rainfallc) altituded) latitude

Types:a) Tropical rain forest - found in area of the equator where rainfall is abundant

- has the greatest diversity of species of all communitiesb) Temperate deciduous forest – found most in eastern United States and in Europe

- consist of shrubs, dominated by oak and maple trees- trees become dormant during winter and produce new leaves each

springc) Taiga – also known as coniferous forest or boreal forest

- dominated by evergreen needle shaped trees- pines, spruce etc..d) Savanna – also known as tropical grassland

- fires are frequent therefore vegetation are fire adapted- with grazing and browsing animals

e) Tundra - characterized by permafrost which is the frozen layer of the soil- climate is very cold for most of the year with little light available

f) Desert – arid, dry with wide and sparse vegetation

- with low and unpredictable precipitation