Assuming that a city wishes to manage its water supply in a ...

[cagreen833]

Assuming that a city wishes to manage its water supply in a sustainable manner, describe/explain two specific factors that must be considered in order to accomplish this.
 
  What will be an ideal response?

Question 2

What does the fossil charcoal record tell us about atmospheric O2 levels?
 
  What will be an ideal response?

[succesfull]

Answer to Question 1

To be sustainable, actions must conform to the laws of mass and energy conservation. This is, something cannot be created from nothing, and everything goes somewhere. In order to manage a municipal water supply sustainably, one must understand the rate of renewal of the water source (is the source a mountain snowfield, constantly renewed, or is the source a more finite groundwater aquifer?). Secondly, one must have the ability and take the initiative to manage the rate of use of this water supply, based on changes in the area's population growth, also factoring in any new demands for this water supply with time (new land uses evolving, such as increased levels of agriculture).

Answer to Question 2

There has been a continuous record of charcoal in sediments dating younger than 360 million years old. This indicates that O2 levels have not been greater than 1.5 PAL or less than 0.5 PAL during this time frame.