ESS EXAM QUESTIONS WITH VERIFIED ANSWERS
Identify four ways in which solar energy reaching vegetation may be lost from an
ecosystem before it contributes to the biomass of herbivores. - Answers - reflected from
the surface of a leaf, absorbed by non-photosynthetic surface, some heat/wavelengths
are absorbed by the leaf but not used in photosynthesis/not converted into chemical
energy, eaten but not absorbed by herbivore/lost in faeces, absorbed by herbivore but
lost through respiration.
Suggest a series of procedures that could be used to estimate the net productivity of an
insect population in kg m-2 yr-1 . - Answers - measure change in population size over
year; using Lincoln Index/mark-release-recapture; set traps/capture a sample, mark and
release them; re-set traps for a second capture and calculate the proportion marked and
unmarked; use the equation: × = 1 2 3 n n N n ;
To what extent are the concepts of net productivity and natural income useful in
managing the sustainable harvesting of named resources from natural ecosystems? [ -
Answers -
explain how climate with high year round temperatures and lots of rainfall affect gross
primary productivity. - Answers - these conditions will promote high gross primary
productivity as the year round precipitation means that the water supply is not limited
and thus, allows for rapid plant growth. The consistently warm temperatures all year
round also contribute to plant growth all year round and rapid nutrient cycling.
Outline one advantage for local populations within the Coral Triangle in harvesting their
food from the marine system - Answers - it does not occupy land (needed for population
/ housing / wilderness area) / less deforestation;fewer resources/inputs required / it is
cheap/free (if harvested themselves);there is natural income available (if harvested
sustainably)/annual yield from natural capital;it satisfies cultural preferences;diverse
range of species/food available (within Coral Triangle);high in nutrients/protein/essential
minerals such as iodine;weather events (droughts/floods/hurricanes) are less likely to
destroy food sources;
Outline one advantage for local populations within the Coral Triangle in harvesting their
food from terrestrial agriculture. - Answers - production is more efficient because of less
loss of light energy;[1max]iti s more efficient because food chain is shorter / more
efficient as food isharvested from lower trophic level;it i s more readily harvested
because it is less dispersed;easier to harvest / less dangerous / requires less
equipment;greater diversity of food products/crops / people decide what to
grow;reduces threat to marine habitats from overfishing / reduces damage t o
marineecosystems from fishing / reduces overfishing rates / conserving
marineecosystems can make them more attractive for recreational use/tourism;good
, growing condition in the area for crop growth / high levels of insolation andrainfall
(tropical conditions) in the area promote rapid crop growth
Explain two ways in which mangroves improve the water quality for primary producers
within marine ecosystems. - Answers - Mangroves improve the water quality for primary
producers within marine ecosystems by filtering sediments/particulates/suspended
solids from the environment. In doing so, the mangroves reduce the water's turbidity,
increasing light penetration for phytoplankton, seagrass and coral. Furthermore, this
process reduces sediment deposition on reef systems which would smother/choke it.
Additionally, mangroves absorb nutrients from the water and this is beneficial to the
water quality because it reduces the threat of eutrophication which causes anoxic
conditions that would seriously affect primary producers.
Mangroves can remove heavy metals/toxins/pollutants from the water. This process
maintains water clarity for light penetration that is required for photosynthesis.
Furthermore, it reduces sediment deposition on reef systems that choke it.
Mangroves drop their leaves into the water which decompose and increase nutrient
levels. This process improves growing conditions for primary producers.
Outline two possible effects of climate change on marine coastal ecosystems - Answers
- higher water temperatures could lead to coral bleaching/death; higher water
temperatures could change migration patterns of some species/cause some species to
migrate to cooler water; higher water temperatures could adversely affect reproduction
of some species; higher water temperatures leads to loss of biodiversity because some
species are unable to adapt/have a very narrow acceptable temperature range; higher
water temperatures decreases dissolved oxygen levels resulting in death of fish; higher
temperatures could increase gross primary productivity/warm water species; higher
temperatures can cause mangroves to dry out that reduce habitat for some species;
ocean acidification/lower water pH adversely affects calcifying
species/shellfish/corals/calcareous plankton; more intense/frequency of storms/currents
could damage coral reefs/seagrass/mangroves /coastal ecosystems; sea-level rise
could reduce (shallow water) conditions required for mangroves/corals/seagrasses /
sea-level rise could flood mangrove ecosystem; sea-level rise could increase coastal
erosion / sea-level rise could increase sediment flow into the ocean reducing light
penetration/primary production within marine coastal ecosystems; increase in
precipitation could lower the water salinity that can adversely affect some species /
lower precipitation could increase water salinity that can adversely affect some species;
12. Suggest two strategies that could be used to reduce the threat to coral reefs from
tourism. - Answers - reduce/restrict tourist numbers/boat numbers / use daily quotas for
visitor numbers; ban littering/waste disposal in the threatened areas / develop recycling
programs for plastic waste / fine tourist for littering; ban individual collection of
souvenirs/shells/corals/fish / ban and police trade in threatened species / enforce CITES
regulations on protected coral species; restrict boat speed to reduce damage to wildlife;
Identify four ways in which solar energy reaching vegetation may be lost from an
ecosystem before it contributes to the biomass of herbivores. - Answers - reflected from
the surface of a leaf, absorbed by non-photosynthetic surface, some heat/wavelengths
are absorbed by the leaf but not used in photosynthesis/not converted into chemical
energy, eaten but not absorbed by herbivore/lost in faeces, absorbed by herbivore but
lost through respiration.
Suggest a series of procedures that could be used to estimate the net productivity of an
insect population in kg m-2 yr-1 . - Answers - measure change in population size over
year; using Lincoln Index/mark-release-recapture; set traps/capture a sample, mark and
release them; re-set traps for a second capture and calculate the proportion marked and
unmarked; use the equation: × = 1 2 3 n n N n ;
To what extent are the concepts of net productivity and natural income useful in
managing the sustainable harvesting of named resources from natural ecosystems? [ -
Answers -
explain how climate with high year round temperatures and lots of rainfall affect gross
primary productivity. - Answers - these conditions will promote high gross primary
productivity as the year round precipitation means that the water supply is not limited
and thus, allows for rapid plant growth. The consistently warm temperatures all year
round also contribute to plant growth all year round and rapid nutrient cycling.
Outline one advantage for local populations within the Coral Triangle in harvesting their
food from the marine system - Answers - it does not occupy land (needed for population
/ housing / wilderness area) / less deforestation;fewer resources/inputs required / it is
cheap/free (if harvested themselves);there is natural income available (if harvested
sustainably)/annual yield from natural capital;it satisfies cultural preferences;diverse
range of species/food available (within Coral Triangle);high in nutrients/protein/essential
minerals such as iodine;weather events (droughts/floods/hurricanes) are less likely to
destroy food sources;
Outline one advantage for local populations within the Coral Triangle in harvesting their
food from terrestrial agriculture. - Answers - production is more efficient because of less
loss of light energy;[1max]iti s more efficient because food chain is shorter / more
efficient as food isharvested from lower trophic level;it i s more readily harvested
because it is less dispersed;easier to harvest / less dangerous / requires less
equipment;greater diversity of food products/crops / people decide what to
grow;reduces threat to marine habitats from overfishing / reduces damage t o
marineecosystems from fishing / reduces overfishing rates / conserving
marineecosystems can make them more attractive for recreational use/tourism;good
, growing condition in the area for crop growth / high levels of insolation andrainfall
(tropical conditions) in the area promote rapid crop growth
Explain two ways in which mangroves improve the water quality for primary producers
within marine ecosystems. - Answers - Mangroves improve the water quality for primary
producers within marine ecosystems by filtering sediments/particulates/suspended
solids from the environment. In doing so, the mangroves reduce the water's turbidity,
increasing light penetration for phytoplankton, seagrass and coral. Furthermore, this
process reduces sediment deposition on reef systems which would smother/choke it.
Additionally, mangroves absorb nutrients from the water and this is beneficial to the
water quality because it reduces the threat of eutrophication which causes anoxic
conditions that would seriously affect primary producers.
Mangroves can remove heavy metals/toxins/pollutants from the water. This process
maintains water clarity for light penetration that is required for photosynthesis.
Furthermore, it reduces sediment deposition on reef systems that choke it.
Mangroves drop their leaves into the water which decompose and increase nutrient
levels. This process improves growing conditions for primary producers.
Outline two possible effects of climate change on marine coastal ecosystems - Answers
- higher water temperatures could lead to coral bleaching/death; higher water
temperatures could change migration patterns of some species/cause some species to
migrate to cooler water; higher water temperatures could adversely affect reproduction
of some species; higher water temperatures leads to loss of biodiversity because some
species are unable to adapt/have a very narrow acceptable temperature range; higher
water temperatures decreases dissolved oxygen levels resulting in death of fish; higher
temperatures could increase gross primary productivity/warm water species; higher
temperatures can cause mangroves to dry out that reduce habitat for some species;
ocean acidification/lower water pH adversely affects calcifying
species/shellfish/corals/calcareous plankton; more intense/frequency of storms/currents
could damage coral reefs/seagrass/mangroves /coastal ecosystems; sea-level rise
could reduce (shallow water) conditions required for mangroves/corals/seagrasses /
sea-level rise could flood mangrove ecosystem; sea-level rise could increase coastal
erosion / sea-level rise could increase sediment flow into the ocean reducing light
penetration/primary production within marine coastal ecosystems; increase in
precipitation could lower the water salinity that can adversely affect some species /
lower precipitation could increase water salinity that can adversely affect some species;
12. Suggest two strategies that could be used to reduce the threat to coral reefs from
tourism. - Answers - reduce/restrict tourist numbers/boat numbers / use daily quotas for
visitor numbers; ban littering/waste disposal in the threatened areas / develop recycling
programs for plastic waste / fine tourist for littering; ban individual collection of
souvenirs/shells/corals/fish / ban and police trade in threatened species / enforce CITES
regulations on protected coral species; restrict boat speed to reduce damage to wildlife;
