Antropogenic disturbances

Question 1

Organic pollution

Answer 1

input of organic matter into waters and the resulting reduction/depletion of DO and high ammonia concentrations –> disappearance of fish and invertebrates

Question 2

saprobity

Answer 2

state of an aquatic ecosystem resulting from the input, decomposition and removal of organic matter
can be asserted by metabolic-dynamic measurements and analysis of living communities

Question 3

frameworks

Answer 3

water frmework directive
urban water treatment directive
integrated pollution prevention
control directive
nitras directive

Question 4

Eutrophication

Answer 4

scetch

Impacts: deadzones, harmful algae bloom, biodiversity loss, increase airborne toxic contaminants

Question 5

Thermal pollution

Answer 5

most common cause: using water for cooling for power plants

stress or death , decreases oxygen availability, alters nutrient cycles, makes waterbody vulnerable to chemicals

Question 6

Acidification

Answer 6

acid rain (directly or though catchments
can be naturally buffered by type of soil
low H –> toxic effect n some organisms and can slo cause the release of toxic metal from sediments
limestone can be added
recovery can take decades

Question 7

Salinization - types

Answer 7

Primary (natural): Rainfall, rock weathering, seawater intrusion and aerosol deposits

Secondary salinization (exacerbation of natural processes
- highly saline irrigation flows from agriculture
- more rapid chemical weathering because of construction
- application of salt to roads

Question 8

Salinization

Answer 8

electrical conductivity –> increased energetic demand to maintain homeostasis
ions can be toxic
effects on humans

Question 9

Salinization - combatting

Answer 9

Changing agricultural practices that use less water (less salt polluted water as runoff)
reducing use of salt as deicers
treat point sources before they are discharged into frehwater

Question 10

Invasive spezcies

Answer 10

is an alien sppecies (specimen introduced outside of it’s natural range that might reproduce) whose introduction has been found to threaten or adverely impact upon biodiversity

One of the biggest threats to biodiversity and the secon leading cause to animal extinction

pathways: aquaframing, fisheries, pet trade (America and east asia)

Question 11

Invasive species - combatting

Answer 11

Prevention: bans on breeding, placement on the market, use of certain species as well as the treatment of ballast water from ships before being discharged

Early detection and rapid eradication: survey and detect IAS and eradicate them as soon as possible

Management: prevention from spreading further –> population conrol

Question 12

Hydrological regime

Answer 12

Rivers: quantity and dynamics of flow, connection to ground water

Lakes: same as rivers + residence time

Question 13

Morphological conditions

Answer 13

Rivers: depth/width variations, structure/substrate of riverbed, strucute riparian zone

Lakes, depth variation, quantity/structue/substrate of lakebed, structure of shore

Question 14

River continuity

Answer 14

Possibility of sediment and migratory species to pass along the river

Question 15

River typology, reference conditions

Answer 15

based pon bioregion, altitude and catchment size

Question 16

Morphological alternations

Answer 16

Bank dynamic: stabilization of riverbanks, change in river profile and connectivity to floodplains -> loss of diversity and space for retreat at disasters

Bed dynamic: stabilization of riverbeds, change in connection to roundwater -> reduced oxygen supply, clogging

Instream structures: natural structures in
stream, removal -> loss of spooning sites and diversity

Bank vegetation: regulation of microclimate, source of nutrition -> changes of light regime and nutrient supply

Course changes

Question 17

Hydrological alternations

Answer 17

Water abstraction, minimum flow: reduction in flow -> barriers for fish, loss of space for retreat

Hydro peaking: change in flow -> species drift, changes in sediment regime

Impoundments: change in flow velocity, sediment transport and erosion -> reduced oxygen, change
in sediment composition, clogging

Question 18

River continuity interruption

Answer 18

River and habitat continuity interruption, change in sediment transport –> barriers for fish, loss of space for retreat

Question 19

Response measure

Answer 19

Responses can vary largely, a few exampls would be fish passes, river restorations or minimum flow surveys