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1.
The purpose of this paper is to study the impacts of the vagueness about the transfer of the harvest right on the use of a natural resource. We develop one-period non-cooperative game frameworks to examine whether the choice of the resource owner to be hazy about the transmission of the harvest contract is optimal. In the perfect information situation, we show that it is optimal for the resource owner to forbid the transfer of the harvest right instead of being hazy about it when the transfer fees are lesser than the collected net punishment fines of the monitoring costs even though the resource would be inefficiently used. In particular, we find in this case that the government’s announcement to forbid the transfer of the right should be public. We further show that there are subgame Nash equilibria in the perfect information context and a unique Nash equilibrium in the imperfect information setting. Specifically, we show that, when the transfer fees are greater or equal to the (net) punishment fines, there is a Nash equilibrium both in perfect and imperfect information situations, precisely when the owner chooses to allow the transfer of harvest title and the resource harvester transfers it.  相似文献   
2.
Gaseous nitrogen dioxide (NO2) represents an oxidant that is present in relatively high concentrations in various indoor settings. Remarkably increased NO2 levels up to 1.5 ppm are associated with homes using gas stoves. The heterogeneous reactions of NO2 with adsorbed water on surfaces lead to the generation of nitrous acid (HONO). Here, we present a HONO source induced by heterogeneous reactions of NO2 with selected indoor paint surfaces in the presence of light (300 nm?<?λ?<?400 nm). We demonstrate that the formation of HONO is much more pronounced at elevated relative humidity. In the presence of light (5.5 W m?2), an increase of HONO production rate of up to 8.6?·?109 molecules cm?2 s?1 was observed at [NO2]?=?60 ppb and 50 % relative humidity (RH). At higher light intensity of 10.6 (W m?2), the HONO production rate increased to 2.1?·?1010 molecules cm?2 s?1. A high NO2 to HONO conversion yield of up to 84 % was observed. This result strongly suggests that a light-driven process of indoor HONO production is operational. This work highlights the potential of paint surfaces to generate HONO within indoor environments by light-induced NO2 heterogeneous reactions.  相似文献   
3.
Dispersers are expected to assess breeding habitat quality before settlement. Although cues reflecting habitat quality are well studied, social cues have not been as well evaluated. In this paper, we studied breeding habitat selection during 3 years in a natural population of blue tits, Cyanistes caeruleus, breeding in nest-boxes. Our aim was to investigate if this species used conspecific density and/or reproductive success of con- and heterospecifics (i.e., social cues) in settlement decisions. The patterns observed were consistent with the idea that juveniles, when dispersing from their natal patches, did not react to any of the cues that we tested. In contrast, breeders that dispersed seemed to respond to both conspecific mean patch reproductive success (PRS) and breeding density of the settlement patch in the year of dispersal, their response differing according to their own reproductive success. Indeed, failed breeders moved to areas with high PRS and low density relative to source patches, while successful breeders behaved the opposite. The comparison between juveniles and adults might be modulated by the limited time available to juveniles to gather information on PRS and density at the end of the dispersing year. Adults lacking these time constraints, however, seemed to rely on these conspecific cues although limited by their own quality. Additionally, breeders were more likely to be immigrants in patches with relatively low breeding success and density the previous year, suggesting that settlement is influenced by multiple cues, which may reveal information on different aspects of habitat and be available at different moments. Collectively, our results support the importance of social cues for blue tits’ settlement.  相似文献   
4.
CO2 injection into a depleted hydrocarbon field or aquifer may give rise to a variety of coupled physical and chemical processes. During CO2 injection, the increase in pore pressure can induce reservoir expansion. As a result the in situ stress field may change in and around the reservoir. The geomechanical behaviour induced by oil production followed by CO2 injections into an oil field reservoir in the Paris Basin has been numerically modelled. This paper deals with an evaluation of the induced deformations and in situ stress changes, and their potential effects on faults, using a 3D geomechanical model. The geomechanical analysis of the reservoir–caprock system was carried out as a feasibility study using pressure information in a “one way” coupling, where pressures issued from reservoir simulations were integrated as input for a geomechanical model. The results show that under specific assumptions the mechanical effects of CO2 injection do not affect the mechanical stability of the reservoir–caprock system. The ground vertical movement at the surface ranges from ?2 mm during oil production to +2.5 mm during CO2 injection. Furthermore, the changes in in situ stresses predicted under specific assumptions by geomechanical modelling are not significant enough to jeopardize the mechanical stability of the reservoir and caprock. The stress changes issued from the 3D geomechanical modelling are also combined with a Mohr–Coulomb analysis to determine the fault slip tendency. By integrating the stress changes issued from the geomechanical modelling into the fault stability analysis, the critical pore pressure for fault reactivation is higher than calculated for the fault stability analysis considering constant horizontal stresses.  相似文献   
5.
The radial and vertical distributions of radiocaesium, potassium and calcium were determined in two Scots pine stands (17 and 58 yr old) similarly affected by the Chernobyl fallout. For both age classes, concentrations are always the lowest in the stemwood, highest in the inner bark and intermediary levels were observed for the outer bark. Due to the cumulative character of its biomass. however. stemwood is a long-term major reservoir of 137Cs. With tree development, changes in the 137Cs radial distribution are well described by variations in the sap ascent pattern and reveal an important transfer between tree rings. It is shown that. both the biomass evolution and knowledge of the evolution of the 137Cs radial gradient are important to predicting 137Cs accumulation in wood with time. According to the common transfer factor (TF) approach, one would expect a decrease in radiocaesium accumulation with time (from 0.0047 +/- 0.0013 to 0.0035 +/- 0.0008 m2kg(-1) for the 17 and 58 yr old trees, respectively). With the wood immobilisation potential (WIP) approach, it was, however, clearly shown that additional annual uptake was highest for the older stand (3.12 +/- 0.23 Bq cm(-3) yr(-1) for the 58-year-old stand compared to 1.99 +/- 0.30 Bq cm(-3) yr(-1) for the younger stand). Following the WIP approach, it was moreover possible to distinguish between the 137Cs incorporated via the root uptake process and a possible lasting effect of interception. It is shown that, whereas for the younger stand (5 yr old at the time of the accident) root uptake contributed exclusively to the wood contamination, the former process explained only 48% of the measured total 137Cs content in the wood of the older tree.  相似文献   
6.
This study was conducted to identify the principle selenate carrier phases for two selected soils, by comparing their reactivity with selenate to that of pure phases of the solids. Silica, calcium carbonate, aluminium hydroxide, goethite, bentonite and humic acid were selected as the main soil carrier phases. Comparisons were made first on the parameter values obtained with the best fit of a kinetic sorption model which can discriminate instantaneous sorption from kinetically limited sorption. Then comparisons were made of the ability for each solid to stabilise selenate by measuring the ratio of the partition coefficient for sorption (Kdsorption) over that of the desorption (Kddesorption). Kinetics and stabilisation were used to help elucidate the nature of interactions with the test solid phases for a large range of selenate concentrations. The experiments were conducted over 165 h in batch reactors, the solid being isolated from the solution by dialysis tubing, at two pH (5.4 and 8) and three selenate concentrations (1 × 10−3, 1 × 10−6 and 1 × 10−8 mol L−1). The results obtained showed that only aluminium hydroxide can sorb selenate throughout the studied pH range (pH 5.4 to 8.0). The sorption capacity on this mineral was high (Kdsorption > 100 to 1 × 104 L kg−1) and the selenate was mainly stabilized by the formation of inner sphere complexes. The sorption on goethite occurred at pH 5.4 (Kdsorption 52 L kg−1), mainly as outer sphere complexes, and was null at pH 8. On silica, a weak sorption was observed only at pH 5.4 and at 165 h (Kdsorption 4 L kg−1). On bentonite, calcium carbonate and humic acid no significant sorption was observed. Concerning the two soils studied, different behaviours were observed for selenate. For soil Ro (pH 5.4), Kdsorption was low (8 L kg−1) compared to soil Bu (pH 8) (70 L kg−1). The sorption behaviour of selenate on soil Ro was mainly due to outer sphere complexes, as for goethite, whereas for soil Bu the sorption was mainly attributed to inner sphere complexes followed by reduction mechanisms, probably initiated by microorganisms, in which no steady state was reached at the end of the 165 h experiments. The sorption of selenate decreased when concentrations reached 1 × 10−3 mol L−1, due to solid saturation, except for aluminium hydroxide. Reduction of selenate seemed also to occur on goethite and soil Ro, for the same concentration, but without preventing a decrease in sorption. Thus, this work shows that the comparison of selenate behaviour between soil and pure phases helps to elucidate the main carrier phases and sorption mechanisms in soil.  相似文献   
7.
Liquid manure storages are a significant source of methane (CH4) emissions. Farmers commonly agitate (stir) liquid manure prior to field application to homogenize nutrients and solids. During agitation, manure undergoes mechanical stress and is exposed to the air, disrupting anaerobic conditions. This on-farm study aimed to better understand the effects of agitation on CH4 emissions, and explore the potential for intentional agitation (three times) to disrupt the exponential increase of CH4 emissions in spring and summer. Results showed that agitation substantially increased manure temperature in the study year compared to the previous year, particularly at upper- and mid-depths of the stored manure. The temporal pattern of CH4 emissions was altered by reduced emissions over the subsequent week, followed by an increase during the second week. Microbial analysis indicated that the activity of archaea and methanogens increased after each agitation event, but there was little change in the populations of methanogens, archaea, and bacteria. Overall, CH4 emissions were higher than any of the previous three years, likely due to warmer manure temperatures that were higher than the previous years (despite similar air temperatures). Therefore, intermittent manure agitation with the frequency, duration, and intensity used in this study is not recommended as a CH4 emission mitigation practice.

Implications: The potential to mitigate methane emissions from liquid manure storages by strategically timed agitation was evaluated in a detailed farm-scale study. Agitation was conducted with readily-available farm equipment, and targeted at the early summer to disrupt methanogenic communities when CH4 emissions increase exponentially. Methane emissions were reduced for about one week after agitation. However, agitation led to increased manure temperature, and was associated with increased activity of methanogens. Overall, agitation was associated with similar or higher methane emissions. Therefore, agitation is not recommended as a mitigation strategy.  相似文献   
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10.
Summary. The diterpene neocembrene A or (1E,5E,9E,12R)-1,5,9-trimethyl-12-(1-methylethenyl)-1,5,9-cyclotetradecatriene, known as the trail-following pheromone of the advanced Termitidae Nasutitermitinae Nasutitermes exitiosus and Trinervitermes bettonianus, has been identified after SPME-GC/MS as the major component of the trail-following pheromone of the Rhinotermitidae Prorhinotermitinae, Prorhinotermes canalifrons and P. simplex. In all the other Rhinotermitidae studied until now, the major component of their trail pheromones is dodecatrienol ((3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol). This biochemical data further add to the anatomical and molecular characteristics that give a special status to the taxon Prorhinotermes among Rhinotermitidae. In Prorhinotermes canalifrons and P. simplex, neocembrene A was the only secretory compound specific to the sternal gland surface that could be detected after SPME. It elicited orientation as well as recruitment behavioral effects. However, the comparison of the respective biological activities triggered by neocembrene A and by sternal gland secretion suggests that minor components of the latter are acting in synergy with neocembrene A.  相似文献   
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