The services of ecological systems and the natural capital stocks that produce them are critical to the functioning of the Earth's life-support system. They contribute to human welfare, both directly and indirectly, and therefore represent part of the total economic value of the planet. We have estimated the current economic value of 17 ecosystem services for 16 biomes, based on published studies and a few original calculations. For the entire biosphere, the value (most of which is outside the market) is estimated to be in the range of US$16-54 trillion (10^(12)) per year, with an average of US$33 trillion per year. Because of the nature of the uncertainties, this must be considered a minimum estimate. Global gross national product total is around US$18 trillion per year.

https://www.esd.ornl.gov/benefits_conference/nature_paper.pdf

The value of the world's ecosystem services and natural capital

Humans are altering the composition of biological communities through a variety of activities that increase rates of species invasions and species extinctions, at all scales, from local to global. These changes in components of the Earth's biodiversity cause concern for ethical and aesthetic reasons, but they also have a strong potential to alter ecosystem properties and the goods and services they provide to humanity. Ecological experiments, observations, and theoretical developments show that ecosystem properties depend greatly on biodiversity in terms of the functional characteristics of organisms present in the ecosystem and the distribution and abundance of those organisms over space and time. Species effects act in concert with the effects of climate, resource availability, and disturbance regimes in influencing ecosystem properties. Human activities can modify all of the above factors; here we focus on modification of these biotic controls. The scientific community has come to a broad consensus on many aspects of the re- lationship between biodiversity and ecosystem functioning, including many points relevant to management of ecosystems. Further progress will require integration of knowledge about biotic and abiotic controls on ecosystem properties, how ecological communities are struc- tured, and the forces driving species extinctions and invasions. To strengthen links to policy and management, we also need to integrate our ecological knowledge with understanding of the social and economic constraints of potential management practices. Understanding this complexity, while taking strong steps to minimize current losses of species, is necessary for responsible management of Earth's ecosystems and the diverse biota they contain.

/pdf/effects-of-biodiversity-on-ecosystem-functioning-a-consensus-13j8vabcus.pdf

Effects of biodiversity on ecosystem functioning: a consensus of current knowledge

Freshwater biodiversity is the over-riding conservation priority during the International Decade for Action - 'Water for Life' - 2005 to 2015. Fresh water makes up only 0.01% of the World's water and approximately 0.8% of the Earth's surface, yet this tiny fraction of global water supports at least 100000 species out of approximately 1.8 million - almost 6% of all described species. Inland waters and freshwater biodiversity constitute a valuable natural resource, in economic, cultural, aesthetic, scientific and educational terms. Their conservation and management are critical to the interests of all humans, nations and governments. Yet this precious heritage is in crisis. Fresh waters are experiencing declines in biodiversity far greater than those in the most affected terrestrial ecosystems, and if trends in human demands for water remain unaltered and species losses continue at current rates, the opportunity to conserve much of the remaining biodiversity in fresh water will vanish before the 'Water for Life' decade ends in 2015. Why is this so, and what is being done about it? This article explores the special features of freshwater habitats and the biodiversity they support that makes them especially vulnerable to human activities. We document threats to global freshwater biodiversity under five headings: overexploitation; water pollution; flow modification; destruction or degradation of habitat; and invasion by exotic species. Their combined and interacting influences have resulted in population declines and range reduction of freshwater biodiversity worldwide. Conservation of biodiversity is complicated by the landscape position of rivers and wetlands as 'receivers' of land-use effluents, and the problems posed by endemism and thus non-substitutability. In addition, in many parts of the world, fresh water is subject to severe competition among multiple human stakeholders. Protection of freshwater biodiversity is perhaps the ultimate conservation challenge because it is influenced by the upstream drainage network, the surrounding land, the riparian zone, and - in the case of migrating aquatic fauna - downstream reaches. Such prerequisites are hardly ever met. Immediate action is needed where opportunities exist to set aside intact lake and river ecosystems within large protected areas. For most of the global land surface, trade-offs between conservation of freshwater biodiversity and human use of ecosystem goods and services are necessary. We advocate continuing attempts to check species loss but, in many situations, urge adoption of a compromise position of management for biodiversity conservation, ecosystem functioning and resilience, and human livelihoods in order to provide a viable long-term basis for freshwater conservation. Recognition of this need will require adoption of a new paradigm for biodiversity protection and freshwater ecosystem management - one that has been appropriately termed 'reconciliation ecology'.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/96AA265E3D88C95FB802E7A73CCB4332/S1464793105006950a.pdf/div-class-title-freshwater-biodiversity-importance-threats-status-and-conservation-challenges-div.pdf

Freshwater biodiversity: importance, threats, status and conservation challenges

In 1974 an article appeared in Science magazine with the dry-sounding title “Judgment Under Uncertainty: Heuristics and Biases” by a pair of psychologists who were not well known outside their discipline of decision theory. In it Amos Tversky and Daniel Kahneman introduced the world to Prospect Theory, which mapped out how humans actually behave when faced with decisions about gains and losses, in contrast to how economists assumed that people behave. Prospect Theory turned Economics on its head by demonstrating through a series of ingenious experiments that people are much more concerned with losses than they are with gains, and that framing a choice from one perspective or the other will result in decisions that are exactly the opposite of each other, even if the outcomes are monetarily the same. Prospect Theory led cognitive psychology in a new direction that began to uncover other human biases in thinking that are probably not learned but are part of our brain’s wiring.

Thinking fast and slow.

http://portal.nceas.ucsb.edu/working_group/ebm-matrix/pdf-reprints/de%20Groot_2002.pdf/attachment_download/file

A typology for the classification, description and valuation of ecosystem functions, goods and services

This paper provides a test for variation in wage structures across regions. The authors suggest that the appropriate test for structural variation incorporates a combination of two lines of research: structural variation and compensating variation. The model of earnings determination used implies that, while job characteristic prices may be subject to stochastic shocks or industry-specific factors and, hence, may differ between regions, the returns to human capital characteristics will be regionally invariant. The results suggest that the theoretical expectations of regional homogeneity is generally supported for the decade of the 1970s. Copyright 1989 by MIT Press.

Regional Wage Differentials and the Spatial Convergence of Worker Characteristic Prices

The influence of rapid rural-urban migration on Korean national fertility levels

SPECIAL SECTION: FORUM ON VALUATION OF ECOSYSTEM SERVICES The value of ecosystem services: putting the issues in perspective

Regulatory schemes and self-protective environmental risk control: a comparison of insurance, liability, and deposit/refund systems

It is apparent from a recent survey article on migration that additional understanding of migration has come from disaggregating migration flows and analyzing the behavior of more homogeneous subgroups [3]. One type of migration, return migration, has received some theoretical and empirical attention from Vanderkamp [7]. Vanderkamp's migration model is a simple one which incorporates the assumption that gross return migration is a constant proportion of previous gross migration. In a later article [8], he tests the constant proportion assumption and concludes that return migration flows are largely determined by previous migration and not by income in sender and receiver regions or distance between the two regions. The lack of response of return migration to income and distance found in Vanderkamp's study clearly suggests a reduced role for traditional mobility policy variables such as moving subsidies and relocation allowances in stimulating return migration. The purpose of this paper is to present a general migration model of the utility maximizing type in which the direction of migration-migration away from the "home" region, migration back to the "home" region, or neither-is explicitly considered. This paper will test whether the effects of distance and earnings on migration behavior are the same for the three different directions of migration. The first section of the paper presents the appropriate utility maximizing migration model and expectations. The second section describes the data base and presents the empirical results.

Stephen Farber

Papers

Regional Wage Differentials and the Spatial Convergence of Worker Characteristic Prices

The influence of rapid rural-urban migration on Korean national fertility levels

SPECIAL SECTION: FORUM ON VALUATION OF ECOSYSTEM SERVICES The value of ecosystem services: putting the issues in perspective

Regulatory schemes and self-protective environmental risk control: a comparison of insurance, liability, and deposit/refund systems

A Directional Flow Migration Model