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• How can agriculture impact water quality?

  Through wastewater, fertilizers, herbicides, pesticides, and soil erosion
• What is one of the main impacts of agriculture on water quality?

  Eutrophication
• What causes eutrophication?

  • Increase in nitrogen and phosphorus from slurry and fertilizers
  • Leads to nutrient enrichment in water bodies

  
• What is the result of eutrophication on algae?

  It causes algae blooms to increase

  
• How does increased algae growth affect aquatic plants?

  It prevents light from reaching them, leading to increased decomposition
• What is the consequence of increased decomposition in water bodies?

  It decreases oxygen levels
• What happens to consumers in water bodies due to decreased oxygen levels?

  They are reduced in number
• What can occur in water bodies during the autumn season due to eutrophication?

  Anoxia
• Where do dead zones typically occur?

  Near boundary points between river mouths and coastal zones
• What are the three main problems caused by eutrophication?

  1. Excessive growth of algae due to nitrogen
  2. Negative effects on human health
  3. Economic loss from fertilizer loss in agriculture
• What are some ways to resolve eutrophication?

  • Use different types of fertilizers and detergents
  • Pump mud from eutrophic water
  • Remove nitrates and phosphates from water
• How can barley straw help in reducing nitrate loss?

  It uses nitrogen in the process of decay
• What should be avoided when soils are wet to reduce nitrate loss?

  Using nitrogen fertilizers
• Why should nitrogen fertilizers be avoided near streams or lakes?

  To prevent runoff into water bodies
• What happens when grass is ploughed in relation to nitrogen?

  It releases nitrogen into the soil
• What should be done if rain is forecast regarding fertilizer application?

  Avoid applying fertilizer
• What is salinization in the context of irrigation?

  It is the increase of salt in the soil due to evaporation
• What can cause groundwater levels to rise to the surface?

  Capillary forces
• What happens to soluble salts when evaporation occurs?

  They are left behind, making the land toxic
• What is the definition of Integrated River Basin Management (IRBM)?

  IRBM is the process of coordinating conservation, management, and development of water, land, and related resources across sectors within a river basin.
• What was the projected cost of salinization in San Joaquin Valley, California?

  $1–1.5 billion
• What is the main goal of Integrated River Basin Management (IRBM)?

  To maximize economic and social benefits from water resources while preserving freshwater ecosystems.
• What are the components of Integrated Drainage Basin Management (IDBM)?

  • Water quality
  • Water supply
  • Flood control
  • River channels
• What are the impacts of irrigation on water quality?

  • Loss of aquifer capacity due to over-extraction
  • Reduction of the water table (e.g., 50 meters in Texas)
  • Decrease in the world's albedo by 10%
  • Increased evapotranspiration rates in summer
  • Increased hailstorms and tornadoes in irrigated areas
• What is one method of irrigation mentioned in the study material?

  Drip systems
• How does successful drainage basin management operate in relation to the river?

  It works with the river rather than against it.
• How does irrigation affect the albedo of the Earth's surface?

  It reduces the world's albedo by 10%
• What are the seven key elements to successful Integrated Drainage Basin Management (IDBM)?

  1. Integration
  2. Timing
  3. Participation
  4. Scale
  5. Knowledge
  6. Capacity
• How does increased moisture in the soil affect weather patterns in irrigated areas?

  It can lead to more hailstorms and tornadoes
• Why is there a need for Integrated Drainage Basin Management (IDBM) according to the WWF?

  Due to the freshwater crisis and the melting of glaciers increasing river discharge.
• What environmental issue is caused by the melting of glaciers in Pakistan and India?

  It increases discharge in rivers.
• What are glacial outburst floods?

  Floods caused by failures of dams containing a glacial lake.
• What impact does increased land use due to urban development have on drainage basins?

  It contributes to the need for Integrated Drainage Basin Management.
• How does agricultural water use affect Integrated Drainage Basin Management?

  It increases the demand for water resources.
• What percentage of all animals live in freshwater?

  Approximately 12%.
• What are some costs associated with Integrated Drainage Basin Management (IDBM)?

  Costs include difficulties in stakeholder involvement and project expenses.
• What are the benefits of Integrated Drainage Basin Management (IDBM)?

  • Helps preserve biodiversity and maintain ecosystems
  • Ensures sustainable water use
  • Minimizes risks and impacts of flooding
  • Provides a reliable water supply
• What do flood hydrographs show?

  They show how a river channel responds to a storm event.

  
• What two variables do flood hydrographs compare?

  Rainfall received during an event in mm and river discharge in m/sec (cumecs).
• What are the characteristics of the rising limb in a flood hydrograph?

  • Indicates the speed of water increasing in the channel
  • Indicates the amount of discharge
  • Steep in flash floods and small drainage basins
  • Steep in urbanized areas