Award 1 mark for each of the following; 4 marks max

• Urban (paved) surfaces/reduced vegetation cover will lead to an increase in runoff ${\\therefore}$ increase in stream-flow/flooding 1 mark

• Urban (paved) surfaces/reduced vegetation cover will reduce infiltration of water into soils ${\\therefore}$ reduce inputs to groundwater/aquifers/water table level 1 mark

• Urbanization can increase local heat/temperature leading to greater evaporation/downwind precipitation 1 mark

• Urbanization will reduce vegetation cover ${\\therefore}$ reduce evapotranspiration/regional precipitation 1 mark

Urbanization will increase local water extraction reducing river flows/increasing outputs from groundwater storages/aquifers Urbanization may lead to increased emission of greenhouse gases/global warming/climate change that may result in multitude of changes in hydrological cycle e.g. increased melting of glaciers/shifting precipitation patterns/increased evaporation etc.

Ensure that each markpoint includes an explicit link to a direct consequence of urbanization and how this influences a process in the hydrological cycle. Award 1 mark maxfor changes associated with global warming.

Positive changes promoting the value of hydropower:

• rise in environmental awareness/need for renewable energy may increase value of hydropower; 1 mark
• need for industrial development entails increased demand for energy, thus increasing value of hydropower; 1 mark
• improved/more efficient technology of dam building making the political decision more attractive to voters / increasing the margin of profit / reducing the initial investment for LEDCs / making overall project more sustainable; 1 mark
• technological development of small scale/damless projects may render hydropower more aesthetically appealing / cheaper to implement in LEDCs / more environmental-friendly / more fit to ecocentrists; 1 mark
• hydropower may become favoured due to depletion in local non-renewable sources/need for energy security; 1 mark

Negative changes reducing value of hydropower:

• impacts of hydropower on aquatic systems / local human settlements cause increasing conflict with cultural values/local needs; 1 mark
• other renewable resources may become more favourable through technological development/reduced costs; 1 mark
• decreasing rainfall/increased evaporation due to climate change renders an existing dam less efficient / profitable; 1 mark
• energy security reasons / political change / economic recession dictate shift from hydropower to more dense nuclear power / cheaper coal; 1 mark
• societal values/EVS may stop seeing damming of a river as sustainable and demand shift away from river dams to wind/solar power; 1 mark
• society realizing it was unethical to relocate a local tribe and demanding the restoration of the river;1 mark

Award 4 marks max if no balanced discussion present. For full marks, both positive and negative changes linked to hydropower must be discussed, with explanation and justification of conclusion.

• understanding concepts and terminology of water accessibility, distribution, security, scarcity; approaches of different EVS to water management; management policies/legislation; irrigation; domestic use; industrial development; international conflict; water conservation strategies; desalination; artificial recharge of aquifers; rainwater harvesting; grey-water recycling, etc.;
• breadth in addressing and linking changes in human behaviour and technological approaches with a range of water conservation strategies in the context of different societies and geographical locations, etc.;
• examples of water scarcity issues and changes in human behaviour and technological solutions that may address these issues, etc.;
• balanced analysis evaluating the extent to which changes in human behaviour address water scarcity more effectively than technological solutions along with limitations and counterarguments, etc.;
• a conclusion that is consistent with, and supported by, analysis and examples given e.g. "although technological solutions often become necessary when scarcity is particularly severe, changing human behaviours address the root of the problem and have a more widespread affordability";

Marks	Level descriptor
0	The response does not reach a standard described by the descriptors below and is not relevant to the question.
1–3	The response contains:• minimal evidence of knowledge and understanding of ESS issues or concepts • fragmented knowledge statements poorly linked to the context of the question • some appropriate use of ESS terminology • no examples where required, or examples with insufficient explanation/relevance • superficial analysis that amounts to no more than a list of facts/ideas • judgments/conclusions that are vague or not supported by evidence/argument.
4–6	The response contains: • some evidence of sound knowledge and understanding of ESS issues and concepts • knowledge statements effectively linked to the context of the question • largely appropriate use of ESS terminology • some use of relevant examples where required, but with limited explanation • clear analysis that shows a degree of balance • some clear judgments/conclusions, supported by limited evidence/arguments.
7–9	The response contains: • substantial evidence of sound knowledge and understanding of ESS issues and concepts • a wide breadth of knowledge statements effectively linked with each other, and to the context of the question • consistently appropriate and precise use of ESS terminology • effective use of pertinent, well-explained examples, where required, showing some originality • thorough, well-balanced, insightful analysis • explicit judgments/conclusions that are well-supported by evidence/arguments and that include some critical reflection.