L4,L5,L6 Flashcards
modelling nutrient export by rivers (to seas) with models
MARINA & Global news
Global NEWS: what does it take into account
models the global nutrient export from watersheds. takes into account
- anthropogenic diffuse sources (atmospheric N deposition, biological N fixation, fertilizer, manure)
- anthropogenic point sources (sewage)
- natural diffuse sources (atm N deposition, biol N fixation)
in global news, nutrients are exported out of the river by:
- water consumption
- reservoir retention (dams)
- denitrification (N to NO2)
global news inputs and outputs
inputs are at BASIN scale. - human activities (population, urbanization, synthetic fertilizers, atm. n dep, biol n. fixation). also takes land use and hydrology into account
outputs at basin scale
annual river export of nutrients to the river mouth (N, P, C, Si) + source attribution. calculates indicator for ICEP. for the years 1970, 2000, 2030, 2050. different scenarios for the years in the future
indicator for coastal eutrophication potential (ICEP)
ICEP is based on loads and ratios of N, P and Si delivered by rivers to coastal waters. this indicator assumes that excess N or P relative to Si will result in an increased growth of potential harmful algae. positive ICEP: high potential for eutrophication. negative ICEP: low potential for eutrophication
MARINA model
model to assess river inputs of nutrients to seas. marina is on sub-basin level, global news is only for full basins. marina is on subbasin level ánd makes a distinction between up-middle- and down-stream
MARINA inputs and outputs
human activities (population, urbanization, agriculture (synthetic fertilizers, atm. n dep, biol n. fixation)). also takes land use and hydrology into account
what is new compared to global news? direct discharge of animal manure. untreated human waste, updated reservoirs and P retention in sediments
output:
annual river export of nutrients
- dissolved N and P
- source attribution
- sub-basin contribution
sources of pathogens and risk of disease spread
sources of pathogens are human and animal feces. risk of disease spreading through: drinking water, recreational water, irrigated vegetables.
ways to determine if water quality is sufficient
- standards (based on maximum concentration
- health-based targets (based on DALYs)
why modelling for pathogen concentration?
- provides quantitative information on pathogen concentrations and risks in data sparse regions
- can identify pathogen concentrations and risk hotspots
- you can identify areas for improvement that are evidence based
- enables the projection of future concentrations and risks using scenario analysis
- supports health risk management
similarities and differences between microbial and nutrient water quality modelling
- manure and sewage treatment are sources for both
- similar sources and hotspot areas
- uses the same river systems since the processes are the same
- similar (non)-point sources
- does not take into account processes that happen in the soil (difference?)
flood
temporary covering of land by water outside its normal boundaries
how can floods be good?
they bring fertile sediments from the upland to the lowland area. controlled flooding is sometimes used in water management or agriculture (shrimp, rice)
damages a flood can cause
- economic (destroyed houses, cars)
- non-economic (fatalities, injuries)
- direct: damages caused by flooding in the affected areas: water damage to houses, buildings, infrastructure, sewage overflows leading to pollution, evacuation and shelter costs
- indirect damages: damages and costs outside of the flooded area: business losses from businesses outside the affected area, social disruption, electricity disruption, temporary housing, tourism
environmental damage due to flooding
- environmental damage by water dispersion and reaction with released chemicals (soil contamination)
- water resource pollution (leakage of toxic substances to ground and surface waters)
- ignition of flammable and explosive chemical substances floating on the floodwaters (e.g. hydrocarbons)
