13.5 Cycling of Matter

TOPIC: ECOLOGY CYCLES OBJECTIVE: Describe how matter cycles in and out of an ecosystem in water, oxygen , carbon and nitrogen cycles.

13.5 Cycling of Matter

HYDROLOGIC CYCLE: Water cycles through the environment.

• The hydrologic, or water, cycle is the circular pathway of water on Earth.

• Organisms all have bodies made mostly of water.

precipitation condensation transpiration evaporation lake groundwater surface runoff water storage in ocean

13.5 Cycling of Matter

OXYGEN CYCLE:Elements essential for life also cycle through ecosystems .

The main processes involved in the oxygen cycle are photosynthesis and respiration.

13.5 Cycling of Matter

• CARBON CYCLE • Carbon is the building block of life..is an organic cmpd.

– The carbon cycle moves carbon from the atmosphere, through the food web, and returns to the atmosphere.

– Carbon is emitted by the burning of fossil fuels – Remember we exhale CO 2 their food.

that plants take in to make sugar for

carbon dioxide in air combustion respiration photosynthesis respiration decomposition of organisms fossil fuels photosynthesis carbon dioxide dissolved in water

13.5 Cycling of Matter

• NITROGEN CYCLE: mostly underground…78% of atmosphere made of nitrogen but most organisms only can use nitrogen when in form of ammonia or nitrate….so

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Nitrogen fixation – Bacteria convert gaseous nitrogen into ammonia = live in roots of plants nitrogen in atmosphere Nitrifying bacteria- change the ammonium into nitrate which is used by plants to make AA then animals eat plants and it is CYCLED back to atmosphere nitrogen-fixing bacteria in roots animals plant decomposers ammonification nitrogen-fixing bacteria in soil ammonium nitrifying bacteria nitrates nitrites nitrifying bacteria denitrifying bacteria

13.5 Cycling of Matter

PHOSPHORUS CYCLE: all this cycle takes place at and below ground level…not atmospheric and gaseous states