Theme 1 from Rees: the “stock” is not a
fixed quantity
• Resource base = theoretical absolute total
• Proven reserves: known to exist (where well
“measured” to +/- 20%), recoverable based
on:
– Technology
– Demand
– Production costs
– Other price factors (subsidies)
– Availability of substitutes
Theme 1: the “stock” is not
a fixed quantity
Conditional reserves: known to exist, but not
recoverable under current criteria
– Technology: maybe not yet ready at scale
– Demand: just a bit too low still
– Production costs: a bit too high
– Other price factors (subsidies): If gov.
invested more, or required their use, maybe they’d
be exploited more
– Availability of substitutes: maybe already
depressing demand
Exploitation of Stock Resources
Economically-efficient depletion rates for stock
resources:
– Production (yield) is guided by demand and supply---which
sets a price.
– As stock declines (depleiton) price rises and conservation,
recycling, and substitutes
– If supplies produce too much, price declines, not enough,
price increases (oil is good example, and some producers
coordinate to try to affect price, e.g., OPEC).
Problem of “market failures”
• those aspects of resource use that market ignores:
pollution and other externalities, social interest in
conservation, and strategic/security issues (uranium).
Subsidies influence these market mechanisms
Theme 2: the “stock” of renewables
is also not fixed
• Maximum resource potential: what is biological
carrying capacity of Soils? Ocean ? Rivers?
• Sustainable capacity, or “sustained yield”
– Yield without degradation, and expected into future
• Absorptive capacity: especially re: pollution
Externalities: as the most accessible stock resources are depleted, we
go further and further for supply, and often into sensitive environments,
where the externality of ecological impact may be large, or is at least
arguable! You’ll hear more and more about oil resources “locked up” by
laws meant to protect ecosystems, like the Arctic National Wildlife
Refuge—should we go get it?
– Ability to use air, water, soil to absorb wastes w/o
degradation
• Related concept: “carrying capacity:” long-term
renewable species population maintenance or
productivity of an ecosystem.
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Renewables
Some Complications and Uncertainties:
• Science may not know the sustained yield or carrying
capacity.
• Yield or carrying capacity not same every cycle, so
harvest should be adjustable, but demand not easy to
manage (grazing, water, even wildlife).
• Many renewables wrapped up in other ecological values
and services.
Problem of “market failures”
• those aspects of resource use that market ignores:
pollution and other externalities, social interest in
conservation, and strategic/security issues (timber,
species, etc.).
• Production (yield) is still guided by demand and supply--which sets a price, and can push for harvest above
sustainable level (liquidation).
We’ll use as a case study of renewable:
Boulder’s Water Resources
• Water often managed as public resource
• Supply Management: goal is reliable,
sustainable supply, despite large natural
variability, geographical limits; political and
economic constraints.
• Demand management: Goal is efficient use
and conservation. In most “mature” natural
resource systems, a reduced unit demand is
typically as valuable (or more so) as a unit of
increased supply.
• Managers affect supply with these tools:
Regulation / law, rationing, price, technology,
education (you’ll examine this in detail in recitation)
Managing Water Resources
– In theory renewable!
– Water resources: main uses
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Agriculture
Domestic/municipal
Industrial
Power generation (cooling)
– Managed in large systems of collection,
transfer, storage, and supply.
– Domestic supply is seen as a vital “life-line”
resource---a resource that people must have
and is thus often heavily regulated by public
entities (opposed to items like consumer
goods).
Natural variability is key problem in renewable/flow resource management: society tends
to max out it use, but what is max? In a good year maybe twice that of a poor year for
water yield on Boulder Creek---check out 2002! Note that this is long-term (300 y)
record created thru tree-ring analysis (Prof. Connie Woodhouse, now at U.Az.) to help
managers know the long-term yield.
How do water managers manage for variation in supply?
Start reviewing Boulder’s water resources and their management:
Water Resources
http://www.bouldercolorado.gov/index.php?option=com_content&task=view&id=1687&Itemid=1189
• Supply managed through: acquisition of rights,
conveyance and storage of water, supply to
users. Storage regularizes supply.
• Demand managed by: regulation / law, price,
rationing, etc.
• Technology and education can affect demand:
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low flow fixtures
Low-flow irrigation
Low-demand crops, lawns, etc.
Substitution??
• Most waster systems also deal with:
– Quality management
– Instream flow: and ecological uses and services
Natural variability in yield is a big challenge to managers of renewable resources,
especially for those like water which are needed everyday and for which the demand
is relatively inelastic (does not change much as price changes). Boulder water
managers reduce the net variability of the whole system thru diversity of sources,
especially taking water from both sides of the continental divide: east (So. PlatteMissouri-Mississippi; Atlantic) and west (Colorado basin, Pacific)
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Boulder gets some supply from the Colorado, via the
“Colorado-Big Thompson project” which diverts water
under the continental divide thru the Adams Tunnel. It
then is brought via ditch (red line) to Boulder Res.
Denver also gets some of its water (in addition to water from the South Platte,
that runs right thru Denver) from the west slope, via the Roberts Tunnel that
brings water over from Dillon Reservoir on the Blue RI., a tributary to the
Colorado River.
More on Boulder’s Water Resources
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Demand management: In most “mature” natural resource systems
(where demand rise close to supply), a unit of reduced demand is as
valuable (or more so) than unit of increased supply.
Because most urban wayter systems in US are public utilities, often
run by city government, they are not classic “markets”—this may
allow for more management interventions, but also in a democratic
governance allows users to respond to being managed via the ballot
box!
So, managers of resources like water can use tools to affect demand,
and they may use a suite, and worry about not creating too much
resentment among the water users:
– Regulation / law: maybe limit lawn size; or even total water use: often not
very well received by residents.
– Temporary rationing: used by most systems now during droughts: simply
limit use temporarily, usually outdoor use. Residents tolerate this because
it is temporary.
– Pricing: set prices so water cost more epr unit as you use more, called
inverted block pricing, and contrary to the old notion that you get a
discount for bulk purchases.
– Education: teach people that they should conserve and how to do it---often
comes with a bit of persuasion and maybe guilt.
– Technology: provide the technology (low flow faucets, drip irrigation, antievap treatments of lawns, etc.) to reduce use for a given output, and make
that technology available, subsidize it, give it away, or maybe require it
(back to regulation).
Goal: Change resource use
behavior---options include:
•Regulation
•Economics (pricing)
•Technological innovation and
diffusion
•Education, example, guilt, pride,
etc.
•Infrastructure/systems
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