GEOG 310 readings review.docx

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University of British Columbia
ECON 319
Margaret Schabas

The Weather-man is not a moron . -> Why are weather forecasters succeeding when other predictors fail? It's because long ago they came to accept the imperfections in their knowledge. ->For centuries, meteorologists relied on statistical tables based on historical averages. ->Pierre-Simon Laplace postulated that the movement of every particle in the universe should be predictable as long as meteorologists could know the position of all those particles and how fast they are moving. ->The most intuitive way to simplify the problem was to break the atmosphere down into a finite series of boxes, or what meteorologists variously refer to as a matrix, a lattice or a grid. ->The reason that we view coin flips as unpredictable is because when we toss them, we're never able to reproduce the exact same motion. A similar phenomenon applies to the weather. -> Chaos theory, ''Predictability: Does the Flap of a Butterfly's Wings in Brazil Set Off a Tornado in Texas?'' In other words, a small change in initial conditions can produce a large and unexpected divergence in outcomes. -> Chaos theory does not imply that the behavior of the system is literally random. It just means that certain types of systems are very hard to predict. The slightest disturbance to that motion wholly predictable to almost wholly unpredictable. -> First, weather is nonlinear, meaning that it abides by exponential rather than by arithmetic relationships. Second, it's dynamic -- its behavior at one point in time influences its behavior in the future. -> But the Weather Service had explicitly avoided communicating the uncertainty in its forecast to the public, emphasizing only the 49-foot prediction. The forecasters later told researchers that they were afraid the public might lose confidence in the forecast if they had conveyed any uncertainty. -> Since then, the National Weather Service has come to recognize the importance of communicating the uncertainty in its forecasts as completely as possible. ''Uncertainty is the fundamental component of weather prediction. -> Instead of just showing a single track line for a hurricane's predicted path, their charts prominently feature a cone of uncertainty, which many in the business call ''the cone of chaos.'' Biodiversity loss and its impact on humanity.  How such loss of biological diversity will alter the functioning of ecosystems and their ability to provide society with the goods and services needed to prosper.  Loss of certain life forms could substantially alter the structure and functioning of whole ecosystems.  Ecosystem functions, like biomass production and nutrient cycling, respond strongly to changes in biological diversity  BEF (biodiversity and ecosystem functioning). Mathematically based.  BES (biodiversity on ecosystem services). Research built on the idea that ecosystems provide essential benefits to humanity. Main focus on large scale patterns across landscapes relevant to economic or cultural evaluations.  Research on BEF had developed a large body of experiments and mathematical theory describing how genetic, species and functional diversity of organisms control basic ecological processes. Studies on BES were, in contrast, mostly correlative, conducted at the landscape scale and often focused on how major habitat modifications influenced ‘provisioning’ and ‘regulating’ services of ecosystems.  Biodiversity is the variety of life, including variation among genes, species and functional traits. It is often measured as: richness is a measure of the number of unique life forms; evenness is a measure of the equitability among life forms; and heterogeneity is the dissimilarity among life forms.  Ecosystem functions are ecological processes that control the fluxes of energy, nutrients and organic matter through an environment. Examples include: primary production, which is the process by which plants use sunlight to convert inorganic matter into new biological tissue; nutrient cycling, which is the process by which biologically essential nutrients are captured, released and then recaptured; and decomposition, which is the process by which organic waste, such as dead plants and animals, is broken down and recycled.  Ecosystem services are the suite of benefits that ecosystems provide to humanity. Here we focus on two types of ecosystem services—provisioning and regulating. Provisioning services involve the production of renewable resources (for example, food, wood, fresh water). Regulating services are those that lessen environmental change (for example, climate regulation, pest/disease control).  Consensus Statements: 1) There is now unequivocal evidence that biodiversity loss reduces the efficiency by which ecological communities capture biologically essential resources, produce biomass, decompose and recycle biologically essential nutrients. 2) There is mounting evidence that biodiversity increases the stability of ecosystem functions through time. Total resource capture and biomass production are generally more stable in more diverse communities. 3) The impact of biodiversity on any single ecosystem process is nonlinear and saturating, such that change accelerates as biodiversity loss increases. Initial losses of biodiversity in diverse ecosystems have relatively small impacts on ecosystem functions, but increasing losses lead to accelerating rates of change. 4) Diverse communities are more productive because they contain key species that have a large influence on productivity. 5) Loss of diversity across trophic levels has the potential to influence ecosystem functions even more strongly than diversity loss within trophic levels. 6) Functional traits of organisms have large impacts on the magnitude of ecosystem functions, which give rise to a wide range of plausible impacts of extinction on ecosystem function.  Emerging Trends: 1) The impacts of diversity loss on ecological processes may have as quantitatively significant an impact on ecosystem functions as other global change stressors (for example, climate change. 2) Diversity effects grow stronger with time, and may increase at larger spatial scales. 3) More biodiversity is required to maintain the ‘multi-functionality’ of ecosystems at multiple places and times. 4) The ecological consequences of biodiversity loss can be predicted from evolutionary history.  BES: 1) biodiversity per se either directly influences (experimental evidence) or is strongly correlated with (obser- vational evidence) certain provisioning and regulating services. 2) For many of the ecosystem services reviewed, the evidence for effects of biodiversity is mixed, and the contribution of biodiversity per se to the service is less well defined. 3) For many services, there are insufficient data to evaluate the relationship between biodiversity and the service. 4) For a small number of ecosystem services, current evidence for the impact of biodiversity runs counter to expectations. Caution against making sweeping statements that biodiversity always brings benefits to society.  The BEF field has routinely measured functions without extending those to known services, whereas the BES field has routinely described services without understanding their underlying ecological functions. A challenge to linking these two perspectives is that services are often regulated by multiple functions, which do not necessarily respond to changes in biodiversity in the same way.  The need to explore more realistic scenarios of diversity change that reflect how human activities are altering biodiversity is now urgent. Organisms are not lost from ecosystems at random, and traits that predispose species to extinction are often those that drive ecosystem processes  Although there are good estimates of society’s willingness to pay for a number of non-marketed ecosystem services, we still know little about the marginal value of biodiversity on the production of those services. The economic value of biodiversity loss derives from the value of the affected services.  The gains from simplifying ecosystems are often local and short term, whereas the costs are transmitted to people in other locations, or to future generations.  Significant gaps in both the science and policy need attention if the Aichi targets are to be met, and if future ecosystems are to provide the range of services required to support more people sustainably  Understanding of the fundamental ecological processes that link biodiversity, ecosystem functions and services may yet bring the modern era of biodiversity loss to a safe end for humanity. Command and Control and the Pathology of Natural Resource Management.  An ultimate pathology emerges when resource management agencies through initial success with command and control, lose sight of their original purposes, eliminate research and monitoring and focus on efficiency of control.  Golden rule of natural resource management. Natural resource management should strive to retain critical types and ranges of natural variation in resource systems in order to maintain their resiliency. It should facilitate existing processes and variability’s rather than control.  “Command and control” in which a problem is perceived and a solution for its control is developed and implemented.  Command and control approach implicitly assumes that the problem is well-bounded, clearly defined, relatively simple, and generally linear with respect to cause and effect. When this methods are applied to complex, non-linear and poorly understood natural world, then the same predictable outcomes are expected but rarely obtained.  Command and control effort is to move human or ecosystem behaviors to a predetermined, predictable state. Precluding long-term sustainability.  A result of command and control is a reduction of the range of natural variation of systems, in an attempt to increase their predictability or stability. Make ecological systems more reliable for human needs. Ex: Suppression of fires.  The purpose is to turn an unpredictable and inefficient natural system into one that produces products in a predictable and economically efficient way.  Crises are inevitable consequences of a command and control approach to renewable resource management.  When the range of natural variation in a system is reduced the system losses resilience.  Resilience: Conditions far from any equilibrium in which instabilities can flip a system into another regime of behavior-to another stability domain. Resilience is the magnitude of disturbance that can be absorbed or accommodated before the system changes its structure by changing the variables and processes that control system behavior.  An example of resource management in which reduction of variation has led to a less resilient system in the sense of ecosystem resilience: Suppression of fire in fire-prone ecosystems is remarkably successful reducing short-term probability of fire. The consequence is the accumulation of fuel that produces fires of greater intensity. Suppression or removal of a disturbance generally reduces system resilience.  If we use adaptive management in this case policies of fire suppression in naturally fire-prone ecosystems should be eliminated. Develop incentives such as tax reduction to site new housing and other developments away from such areas.  Loss of ecosystem resilience is accompanied by changes in the man
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