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Daly and Farley, Chapters 4-6 (cont’d). GEOG 352: Day 6. Case study outlines due next Thursday. The Garden Club has a table in the Upper Caf til 1:30 today where you can buy fresh produce, and sign up for the Club if you want to.
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Daly and Farley, Chapters 4-6 (cont’d) GEOG 352: Day 6
Case study outlines due next Thursday. The Garden Club has a table in the Upper Caftil 1:30 today where you can buy fresh produce, and sign up for the Club if you want to. Take note that Mike Lewis, author of The Resilience Imperative, will be speaking on campus next Thursday at 5. That should be really good. Any comments or questions about the video on Chad? Today we’ll have Jesse A. and Natasha lead discussions, Then I’ll build on what André presented on Tuesday to go into natural capital in greater depth. Housekeeping Items
Will be going through this material selectively. The goal is to hit the highlights, not master ecological economics in its totality. • As noted by André, there are 8 goods and services provided by nature: • Fossil fuels • Minerals • Water • Land (Ricardian) – distinction between soil and as economic asset • Solar energy • Renewable resources • Ecosystem services • Waste absorption • All of these are forms of natural capital. Chapters 4-6 (cont’d)
The first five are abiotic resources. Fossil fuel energy cannot be recycled whereas minerals can be to some extent. Rivers, lakes and streams share certain common properties with renewable resources. Water replenishes itself, but it can – in the case of fossil aquifers – be depleted, and all fresh water bodies can be contaminated. With respect to fossil fuels, a key concept is EROI – energy return for energy invested. In the 1950s U.S., the EROI was one barrel to extract 50. In 1999, it was 1:5. Chapters 4-6 (cont’d): Abiotic resources
The authors argue that to be minimally sustainable, the EROI has to be at least 3:1. Quickly look up on the Internet and see what it is for shale oil and tar sand oil. • There is also the additional issue that fossil fuel extraction interferes with the collection of solar energy. How is this the case? • What other kinds of ecological impacts/ natural capital depreciation are associated with fossil fuel extraction (and also mineral extraction)? • What kinds of resources are fossil fuels and minerals – stock-flow or fund-service? Chapters 4-6 (cont’d)
Given that matter is governed by the 2nd law, we start with the highest quality minerals, then exploit those of lesser value. With both oil and minerals we don’t know the total stock though we guesstimate. Total stock is also different from what is economically and technically feasible at any given point. We can substitute alternative energy for fossil fuels, but there are no (or few) substitutes for minerals. Citing another author, they point out that there is a distinction to be made between “garbo-junk” (potentially recyclable) and true waste. Chapters 4-6 (cont’d)
Minerals are rival resources within generations, but partially non-rival between generations if stewarded well and recycled. • Fossil fuels are rival within and between generations. • Of the water on the Earth, only 1/3 of 1% if available to us, except through the costly and energy-intensive process of desalination. • Some rivers are so intensely exploited that they no longer reach the sea. • Water is a stock-flow resource when stored in a dam, but a fund-service resource when used for transport, recreation, and ecosystem sustenance. As there is a fixed – and, with climate change, declining -- quantity of water, relative to demand, begins to take the characteristic of a diminishing resource. Chapters 4-6 (cont’d)
The solar energy received by Earth is equivalent to 19 trillion tons of oil per year. However, it is not easy to capture and concentrate unlike oil. Biomass, hydro, wind, photovoltaics, wave, and ocean thermal are all (indirect) forms of solar energy. All of these are subject to various limitations (see p. 90), and all require throughput to produce the equipment and infrastructure. Some may also have questionable EROIs. Others have suggested that massive wind farms could have an impact on weather and climate. Chapters 4-6 (cont’d)
Biotic resources serve three functions: 1) they provide renewable natural resources; 2) they provide ecological services, and 3) they provide waste assimilation capacity. What are some examples of each? Individuals, populations, and species interact to form ecosystems. These are very difficult to understand and manage because of emergent properties/ ecosystem functions (what are?) and non-linear behaviours. This inherent uncertainty suggests the wisdom of the “precautionary principle.” Chapters 4-6 (cont’d): Biotic Resources
This relates to the four different types of uncertainty (p. 95): risk, pure uncertainty, ignorance, and absolute ignorance. • Biotic resources are stock-flow, but unlike other resources are capable of reproduction unless over-used (examples of the latter?). • A key concept in renewable resource management has been sustained yield, but what if we don’t know the total population, the reproduction rate, or how much is “surplus”? • Another key concept is carrying capacity, at which point “there is just enough food and habitat to maintain the existing population, and the rate of growth in biomass is zero” (p. 98). Chapters 4-6 (cont’d): Biotic Resources
Ecosystem services: “We call an ecosystem function that has value for human beings an ecosystem service” (p. 103). See bottom of p. 103 for list of services provided by forests. • Forests are not just ‘timber on the hoof,’ but provide essential ecosystem services. They also are of essential aesthetic and spiritual value. Some have tried to put a price on these values through various methods such as hedonic pricing and other willingness to pay methodologies. • See table on p. 105: Which are rival and which are excludable? • What would be impossible to make excludable? • One cannot substitute for most ecosystem services. Billionaire Edward Bass spent $200 million on Biosphere II that was supposed to support 8 people. It was an utter failure. Chapters 4-6 (cont’d): Biotic Resources
Biosphere II See http://en.wikipedia.org/wiki/Biosphere_2
The final form of natural capital, waste absorption, occurs at a fixed rate. If wastes exceed a certain threshold, disruption occurs with health effects on individuals, species and ecosystems. Examples? This is another form of carrying capacity and has been used as a planning tool in some jurisdictions, such as Lake Tahoe, where the amount of lakeside development is limited by impacts on water quality, since virtually all cottages and chalets are on septic systems. Chapters 4-6 (cont’d): Biotic Resources