Populations & Ecosystems Flashcards
(70 cards)
What are some Carbon stores/sinks in the Carbon cycle
coal,oil,gas, soil and organic matter, sedimens and sedimentary rock, ocean surface, deep ocean, atnosphere
What are some processes in carbon cycle
weathering and run-off, rock formation, sinking sediment, deep circulation, carbon dioxide exchange, burning(e.g. forest fires), burning fossil fuels, respiration, decay, feeding, photosynthesis
How does deforestation impact the carbon cycle?
removes a carbon reservoir, burning releases more to the atmosphere, removes lots of plants which through photo synthesis removes Carbon (CO2)
How does the burning of fossil fuels impact the carbon cycle?
releases lots of greenhouse gases, and is a leader in climate change
How does global warming impact the carbon cycle?
Higher temperatures mean more evaporation so less carbon stored in the ocean = more in atmosphere
more dissolved into oceans at the poles (melting ice) making it more acidic
how does carbon moves through a food chain or web?
the production of carbohydrates, proteins and fats by autotrophs
plant growth
consumption - consumer feeds on another plant or animal it uses the proteins carbohydrates and fats for energy and for raw materials
consumer growth through complex food webs
how is the carbon cycle important in climate change and the greenhouse effect?
carbon sinks (fossil fuels) and (forests) release carbon from human impact
combustion increased releases carbon
removing plants reduces photosynthesis
more carbon absorbed by oceans = acidification
all increase global temperatures and a change in ocean currents/climates
what are some examples of decomposers?
detrivores, fungi, bacteria, protists
what is fragmentation?
initial stage of decomposition, breakdown of detritus into smaller pieces by detrivores
what is leaching?
When water-soluble substances are washed out from the soil, like nutrients, fertilisers or pesticides
what is catabolism?
the conversion of detritus into simpler inorganic compounds. This process is carried out by various fungal and bacterial enzymes
what is humification?
the process of formation of a dark-coloured layer of soil called humus. It cannot be decomposed easily as it is highly resistant to the action of microbes. The layer of humus is very rich in nutrients as it provides high fertility to the soil
what is mineralisation?
final stage of decomposition, degradation of the hummus to release inorganic nutrients
What are the ammonium ions (NH4+) formed in putrefaction converted by, via, and to?
Converted by nitrification, via nitrites (NO2-) to nitrates (NO3-)
What bacteria converts ammonium ions to nitrite, under what conditions?
Nitrosomonas, under aerobic conditions
What bacteria convert nitrite to nitrate, under what conditions?
Nitrobacter, under aerobic conditions
What is nitrogen fixation?
The biological process by which nitrogen in the atmosphere is converted into ammonia
What plant type and where are rhizobium found?
Legumes, in root nodules
Explain the symbiotic relationship between rhizobium and the legumes
Rhizobium use nitrogenase enzyme to split triple bond in nitrogen gas and covert into ammonia and then amino acids which the plant uses for growth.
in return, Rhizobium gains a stable internal environment and utilises glucose made from photosynthesis by the plant
How do Legumes attract rhizobium?
they make leghaemoglobin which binds to oxygen in plant roots, this attracts rhizobium from the soil into the plant roots, leghaemoglobin is a pinky pigment seen in leguminous roots
What is excretion?
the process of removing nitrogenous waste from an organism
what is a legume?
a plant which atmospheric nitrogen is converted into nitrates (peas,beans,clover,gorse)
what is a nodule?
root organ in which rhizobium inhabitat
what is dentrification?
nitrogen is lost from an ecosystem
