Tradable Set-Aside Requirements (TSARs): Conserving Spatially Dependent Environmental Amenities

In the lab, we examine the effectiveness of two land use conservation policies: a tradable set aside requirements (TSARs), and the TSARs combined with an agglomeration bonus. Evaluated by bioeconomic efficiency, our experimental results suggest: 1) TSARs is a cost-effective land conservation tool; and 2) combining TSARS with the agglomeration bonus increases habitat connectivity but at a price—lower economic efficiency.Conservation, tradable development rights, spatial conservation, market instruments

Adaptation and the Option Value of Uncertain Environmental Resources

Just as ecology has benefited from the economic theory of optimization, economics can benefit from the ecological theory of adaptation. We examine the impact of short-term, nongenetic adaptive self-protection on the values individuals attach to uncertain prospective environmental resources. We demonstrate that collective provision of reductions in supply uncertainty does not necessitate a positive option value, given that uncertainty is influenced by the individual\u27s ability to adapt through self-protection. We conclude that the total value of reducing the supply uncertainty of a natural resource is reflected in both the individual\u27s option price payments for collective provision and in his willingness-to-pay for adaptation through self-protection. By ignoring adaptive self-protection, traditional benefit-cost analysis has systematically underestimated the total value of environmental resources that are characterized by uncertain supplies

Tradable Set-Aside Requirements (TSARs): Conserving Spatially Dependent Environmental Amenities

In the lab, we examine the effectiveness of two land use conservation policies: a tradable set aside requirements (TSARs), and the TSARs combined with an agglomeration bonus. Evaluated by bioeconomic efficiency, our experimental results suggest: 1) TSARs is a cost-effective land conservation tool; and 2) combining TSARS with the agglomeration bonus increases habitat connectivity but at a price—lower economic efficiency

Tradable Set-Aside Requirements (TSARs): Conserving Spatially Dependent Environmental Amenities

In the lab, we examine the effectiveness of two land use conservation policies: a tradable set aside requirements (TSARs), and the TSARs combined with an agglomeration bonus. Evaluated by bioeconomic efficiency, our experimental results suggest: 1) TSARs is a cost-effective land conservation tool; and 2) combining TSARS with the agglomeration bonus increases habitat connectivity but at a price—lower economic efficiency

Rheological Microscopy: Local Mechanical Properties from Microrheology

We demonstrate how tracer microrheology methods can be extended to study submicron scale variations in the viscoelastic response of soft materials; in particular, a semidilute solution of lambda-DNA. The polymer concentration is depleted near the surfaces of the tracer particles, within a distance comparable to the polymer correlation length. The rheology of this microscopic layer alters the tracers’ motion and can be precisely quantified using one- and two-point microrheology. Interestingly, we found this mechanically distinct layer to be twice as thick as the layer of depleted concentration, likely due to solvent drainage through the locally perturbed polymer structure

Molecular gas and star formation in early-type galaxies

We present new mm interferometric and optical integral-field unit (IFU) observations and construct a sample of 12 E and S0 galaxies with molecular gas which have both CO and optical maps. The galaxies contain 2 x 10^7 to 5 x 10^9 M\odot of molecular gas distributed primarily in central discs or rings (radii 0.5 to 4 kpc). The molecular gas distributions are always coincident with distributions of optically-obscuring dust that reveal tightly-wound spiral structures in many cases. The ionised gas always approximately corotates with the molecular gas, evidencing a link between these two gas components, yet star formation is not always the domi- nant ionisation source. The galaxies with less molecular gas tend to have [O III]/H{\beta} emission-line ratios at high values not expected for star formation. Most E/S0s with molecular gas have young or intermediate age stellar populations based on optical colours, ultraviolet colours and absorption linestrengths. The few that appear purely old lie close to the limit where such populations would be undetectable based on the mass fractions of expected young to observed old stars. The 8{\mu}m polycyclic aromatic hydrocarbon (PAH) and 24{\mu}m emission yield similar star formation rate estimates of E/S0s, but the total infrared overpredicts the rate due to a contribution to dust heating from older stars. The radio-far infrared relation also has much more scatter than for other star-forming galaxies. However, despite these biases and additional scatter, the derived star formation rates locate the E/S0 galaxies within the large range of the Schmidt-Kennicutt and constant efficiency star formation laws. Thus the star formation process in E/S0s is not overwhelmingly different than in other star-forming galaxies, although one of the more reliable tracers (24{\mu}m) points to a possible lower star-formation efficiency at a given gas surface density.Comment: submitted to MNRA

Finding short GRB remnants in globular clusters: the VHE gamma-ray source in Terzan 5

Globular cluster are believed to boost the rate of compact binary mergers which may launch a certain type of cosmological gamma-ray bursts (GRBs). Therefore globular clusters appear to be potential sites to search for remnants of such GRBs. The very-high-energy (VHE) gamma-ray source HESS J1747-248 recently discovered in the direction of the Galactic globular cluster Terzan 5 is investigated for being a GRB remnant. Signatures created by the ultra-relativistic outflow, the sub-relativistic ejecta and the ionizing radiation of a short GRB are estimated for an expected age of such a remnant of t > 10^4 years. The kinetic energy of a short GRB could roughly be adequate to power the VHE source in a hadronic scenario. The age of the proposed remnant estimated from its extension possibly agrees with the occurrence of such events in the Galaxy. Sub-relativistic merger ejecta could shock-heat the ambient medium. Further VHE observations can probe the presence of a break towards lower energies expected for particle acceleration in ultra-relativistic shocks. Deep X-ray observations would have the potential to examine the presence of thermal plasma heated by the sub-relativistic ejecta. The identification of a GRB remnant in our own Galaxy may also help to explore the effect of such a highly energetic event on the Earth.Comment: 4 pages, accepted for publication in A&A Letter

Valuing Potential Groundwater Protection Benefits

This paper explores the implications of endogenous risk for the economic value of preventing groundwater contamination. We consider the analytical implications of endogenous risk for five key building blocks frequently used to structure studies of groundwater valuation: The probability and the location of contamination, the exposed population, risk perceptions, and Intertemporal issues

Wide Field Photometry of the Galactic Globular Cluster M22

We present wide field photometry of the Galactic Globular Cluster M~22 in the B, V and I passbands for more than 186,000 stars. The study is complemented by the photometry in two narrowband filters centered on H$_{\alpha}$ and the adjacent continuum, and by infrared J, H and K magnitudes derived from the 2 MASS survey for $\sim$2000 stars. Profiting from this huge database, we completely characterized the evolved stellar sequences of the cluster by determining a variety of photometric parameters, including new photometric estimates of the mean metallicity, reddening and distance to the cluster. In particular, from our multi-wavelength analysis, we re-examined the long-standing metallicity spread problem in M~22. According to our dataset, we conclude that most of the observed width of the red giant branch must be due to differential reddening, which amounts to a maximum of $\Delta E(B-V)\simeq0.06$, although the presence of a small metallicity spread cannot be completely ruled out. More specifically, the maximum metallicity spread allowed by our data is of the order of $\Delta$[Fe/H]$\simeq 0.1\div 0.2$ dex, i.e., not much more than what allowed by the photometric errors. Finally, we identified most of the known variable stars and peculiar objects in our field of view. In particular, we find additional evidence supporting previous optical identifications of the central star of the Planetary Nebula IRAS 18333-2357, which is associated with M~22.Comment: 15 pages, 16 figures, accepted for publication in MNRA