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Ecosystem Services economic Valuation (ESV) is often seen as a tool that can potentially enhance our collective choices regarding ecosystem services as it factors in the costs and benefits of their degradation. Yet, to achieve this, the social processes leading to decisions need to use ESV effectively. This makes it necessary to understand if and how ESV is or is not used by decision-makers. However, there appears to be a literature blindspot as to the issue of the Use of Ecosystem Services economic Valuation (UESV). This paper proposes a systematic review on UESV in peer-reviewed scientific literature. It shows that this literature gives little attention to this issue and rarely reports cases where ESV has been put to actual use, even though such use is frequently referred to as founding the goal and justification of ESV. The review identifies three categories of potential UESV: decisive, technical and informative, which are usually mentioned as prospects for the valuations published. Two sets of hypotheses are examined to explain this result: either the use of ESV is a common practice, but is absent from the literature reviewed here; or the use of ESV is effectively rare. These hypotheses are discussed and open up further avenues of research which should make the actual use of ESV their core concern., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Two poly(L-lactide-co-epsilon-caprolactone) random copolymers containing 5 and 40 mol % of epsilon-CL, namely P(LA-co-CL(5)) and P(LA-co-CL(40)), respectively, have been made macroporous by freeze-drying solutions in dimethylcarbonate. Most of the freeze-dried foams, prepared by varying polymer concentration and cooling rate, exhibited two main pore populations: (1). longitudinally oriented tube-like macropores with diameters >or=100 microm, and (2). interconnected micropores (10-100 microm). Pore characteristics, including macropore density, mean diameter, and interdistance, as well as micropore density, area, and shape, were determined by image analysis of scanning electron micrographs in order to study the influence of processing and formulation parameters on foam structure and properties. The pore orientation and the 3-D texture also were studied by image analysis and impedance spectroscopy. In the case of the P(LA-co-CL(5)), the macropore diameter increased with the cooling rate while the micropore diameter decreased. The micropores also became more circular when the cooling rate was increased. The pore size and morphology of the P(LA-co-CL(40)) were quite unchanged by varying the cooling rate. All the other conditions being the same, the P(LA-co-CL(5)) foams were better organized than the P(LA-co-CL(40)) foams, and pore orientation was improved at the higher cooling rate. Pore size and morphology also can be controlled by changing the polymer concentration (Cp), as we showed by studying P(LA-co-CL(5)) foams prepared by freeze-drying solutions in the 1-10 w/v % Cp range. Macropore density, average diameter, and interdistance of P(LA-co-CL(5)) foams increased with Cp, but the micropore characteristics remained almost unchanged no matter the Cp. The reliability of the characterization methods has been discussed, with special attention to mercury intrusion porosimetry, which is used primarily for measurement of pore volume and pore size distribution. However, this technique is reported here as a destructive and unreliable method for the characterization of fragile P(LA-co-CL(40)) foams. This study shows that image analysis and impedance spectroscopy can give reliable information relative to the pore morphology and anisotropy of freeze-dried foams., (Copyright 2003 Wiley Periodicals, Inc.)