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591.
Chen Chen Jessica Hellmann Lea Berrang-Ford Ian Noble Patrick Regan 《Mitigation and Adaptation Strategies for Global Change》2018,23(1):101-122
Equity and efficiency should be considered when allocating resources for climate change adaptation. More than a decade after the Least Developed Countries Fund approved adaptation funds for 18 countries in 2003, it is possible to take the stock of investment data and to test empirically whether equity and efficiency have been factored into adaptation investment decision-making. To evaluate equity, one must determine if resources were distributed to areas of greatest need. Vulnerability assessments provide information on the global distribution of the need for adaptation. To evaluate efficiency, one must compare cost and benefit of an investment. Although it is difficult to assess ex-ante the cost and benefit of investment strategies, it is possible to measure efficient use of expenditures with readiness assessment, as a metric of capacity to deploy adaptation resources. We used vulnerability and readiness measures of the Notre Dame Global Adaptation Initiative (ND-GAIN) Country Index as proxies of equity and efficiency. This article quantitatively interrogates—through the lens of public fund allocation—the roles of vulnerability and readiness in shaping adaptation investment decisions. Our findings suggest that countries facing increasing impacts from climate change have received more adaptation investments from international sources than countries with less vulnerability. Further, international investments also preferentially flow to countries that are more ready to deploy adaptation resources. Since the most vulnerable countries are likely to be less ready for investment, our findings support the efforts to improve the investment potential of the most vulnerable countries by investing first to enhance their readiness, in order to unlock adaptation solutions. 相似文献
592.
Brooke?Erin?CrowleyEmail authorView authors OrcID profile Ian?Castro Voahangy?Soarimalala Steven?M.?Goodman 《Die Naturwissenschaften》2018,105(7-8):44
We applied a multi-isotope approach to examine aspects of niche partitioning, competition, and mobility for rodents in the Central Highlands of Madagascar. Specifically, we used carbon (δ13C), nitrogen (δ15N), and strontium (87Sr/86Sr) isotope ratios in bone to investigate diet and mobility for endemic tufted tail rats (Eliurus spp.), and introduced black rats (Rattus rattus) and house mice (Mus musculus) within and outside a fragment of montane humid forest in the Ambohitantely Special Reserve. There was a clear spatial segregation in trapping success for different species: Eliurus was only in the forest interior and edge, Mus only outside of the fragment in a marsh and park housing complex, and Rattus in all habitats except the housing complex. We find only moderate support for mobility of rodents among habitats. Mus may routinely move between the marsh and housing complex. However, regular movement between the forest edge and interior, or between the forest fragment and surrounding grassland is not supported. Taxa appear to target different foods: Rattus tends to feed at a higher trophic level than Eliurus, and Mus consumes some C4 resources. To date, strontium isotopes have been underutilized in ecological research. Here, we show that they are highly complementary to carbon and nitrogen isotope data. Even in localities with relatively uniform underlying geology, it may be possible to distinguish individuals that regularly forage in different habitats. 相似文献
593.
Ionic liquids(ILs) are a class of solvents increasingly used as "green chemicals." Widespread applications of ILs have led to concerns about their accidental entry to the environment.ILs have been assessed for some environmental impacts;however,little has been done to characterize their potential impacts on drinking water if ILs accidentally enter surface water.IL cations are often aromatic or alkyl quaternary amines that resemble structures of previously confirmed N-nitrosamine(NA) precursors.Therefore,this study has evaluated two common ILs,1-ethyl-3-methylimidazolium bromide(EMIm Br) and 1-ethyl-1-methylpyrrolidinium bromide(EMPyr Br),for their NA formation potential.Each IL species was reacted with pre-formed monochloramine under various laboratory conditions.The reaction mixtures were extracted using liquid–liquid extraction and analyzed for NAs using high performance liquid chromatography tandem mass spectrometry.At low concentration of IL(250 μmol/L),the yields of NAs(NMEA or NPyr) increased with increasing doses of monochloramine from both IL species.The total NA yield was as high as 2.5 ± 0.3 ng/mg from EMIm Br,and as high as 8.6 ± 0.8 ng/mg from EMPyr Br.At high concentration of IL(5 mmol/L),the NA yield reached a maximum at 2.5 mmol/L NH_2Cl,and then decreased with subsequent increases in the reactant concentrations,demonstrating ILs' solvent effects.This study re-emphasizes the importance of preventing discharge of ILs to water bodies to prevent secondary impacts on drinking water. 相似文献
594.
595.
James A. Ryan Ian G. Morison James S. Bethel 《Journal of the American Water Resources Association》1974,10(4):703-709
ABSTRACT: A present concern in decision making processes for forest land use is the environmental effects of land use activities on water, air, and the land itself. Criteria for evaluating the magnitude and detriment of environmental impacts are not definite since it is often difficult to isolate a particular activity as the cause of a particular impact. Instead, interactions between various forest practices must be considered along with their integrated impacts. In order to provide an effective decision tool, the College of Forest Resources, University of Washington, is modeling the forest ecosystem of the Snohomish River Basin located in the Cascade Mountains of western Washington. The project consists of a general system model comprised of subsystem models dealing with product conversion processes, forest production processes, recreation supply processes, wildlife and fisheries supply processes, and the interactions of these processes with water and the atmosphere. The system model is interfaced with a computerized multiple player management game which enables land managers, manufacturing managers, and regulation agency personnel to make management decisions and respond to indications of lack of environmental control. Responses of the hydrologic system to various management decisions are simulated by the water subsystem model. The responses being considered include surface flow quantity and water quality. The model emphasizes the monitoring of non-point as well as point source impacts rather than predicting short-term hydrographs. The significance of impacts vary with land use patterns and the goals of the game player. Therefore, the model has flexible resolution and is able to predict hydrologic conditions for both large and small scale. The water subsystem model responds to management decisions by interpreting the effects of management options selected by game players for 40-acre cells within the Basin. The model then determines which streams are immediately affected, defines the watersheds contributing to these streams, and extracts from a resource data bank the information needed to define model parameters. Using these parameters and precipitation inputs, mean flow discharge on a montly and annual basis is calculated for the impactcd sub watersheds as well as 21 major watersheds of the Basin. Water quality responses predicted for these watersheds include suspended sediment concentration, temperature increases due to stream exposure, dissolved oxygen concentrations, the effects of fertilization on nitrogen content, biocide and herbicide effects, and residues from product conversion processes. 相似文献
596.
Plant-trait-based modeling assessment of ecosystem-service sensitivity to land-use change 总被引:1,自引:0,他引:1
Fabien Quétier Sandra Lavorel Wilfried Thuiller Ian Davies 《Ecological applications》2007,17(8):2377-2386
Evidence is accumulating that the continued provision of essential ecosystem services is vulnerable to land-use change. Yet, we lack a strong scientific basis for this vulnerability as the processes that drive ecosystem-service delivery often remain unclear. In this paper, we use plant traits to assess ecosystem-service sensitivity to land-use change in subalpine grasslands. We use a trait-based plant classification (plant functional types, PFTs) in a landscape modeling platform to model community dynamics under contrasting but internally consistent land-use change scenarios. We then use predictive models of relevant ecosystem attributes, based on quantitative plant traits, to make projections of ecosystem-service delivery. We show that plant traits and PFTs are effective predictors of relevant ecosystem attributes for a range of ecosystem services including provisioning (fodder), cultural (land stewardship), regulating (landslide and avalanche risk), and supporting services (plant diversity). By analyzing the relative effects of the physical environment and land use on relevant ecosystem attributes, we also show that these ecosystem services are most sensitive to changes in grassland management, supporting current agri-environmental policies aimed at maintaining mowing of subalpine grasslands in Europe. 相似文献
597.
598.
The opportunity Value of Travel Time (VTT) is one of the most important elements of the total cost of recreation day-trips and arguably the most difficult to estimate. Most studies build upon the theoretical framework proposed by Becker (1965) by using a combination of revealed and stated preference data to estimate a value of time which is uniform in all activities and under all circumstances. This restriction is relaxed by DeSerpa's (1971) model which allows the value of saving time to be activity-specific. We present the first analysis which uses actual driving choices between open access and toll roads to estimate a VTT specific for recreation trips, thereby providing a value which conforms to both Becker's and DeSerpa's theoretical models. Using these findings we conduct a Monte Carlo simulation to identify generalizable results for subsequent valuation studies. Our results indicate that 3/4 of the wage rate provides a reasonable approximation of the average VTT for recreation trips, while the commonly implemented assumption of 1/3 of the wage rate generates downward biased results. 相似文献
599.
Bertanne Visser Cécile Le Lann Helen Snaas Ian C. W. Hardy Jeffrey A. Harvey 《Behavioral ecology and sociobiology》2014,68(1):105-113
Population-wide mating patterns can select for equal parental investment in both sexes, but limiting resources, such as mates or developmental substrates, can increase competition leading to biased sex ratios in favor of either sex. Such competition for resources typically occurs in spatially structured populations, where dispersal is limited. In this laboratory study, we investigate if and how resource competition affects sex allocation, discriminative behaviors and competitive interactions of the wingless hyperparasitoid Gelis acororum, which exploits patchily distributed hosts. We show that G. acororum sex ratios are male-biased and that this is not a consequence of constrained reproduction by virgin females. Our results suggest that this pattern of reproductive investment, which is only rarely observed in parasitoids, is a consequence of resource limitation, in terms of hosts rather than mates. Further, G. acororum appears not to respond to intrinsic host quality or to prior oviposition in its host. When competing inter-specifically for host resources, G. acororum outcompetes its congener Gelis agilis, but does so mainly when ovipositing on the host first. Overall, our results suggest that host resource limitation could be an important environmental factor shaping sex allocation in G. acororum, with competition taking place both intra- and inter-specifically. 相似文献
600.
Benjamin J. Seligmann Erzsébet Németh Katalin M. Hangos Ian T. Cameron 《Journal of Loss Prevention in the Process Industries》2012,25(4):746-759
A novel hazard identification methodology applied to process systems is presented in this paper. This blended hazard identification (BLHAZID) methodology blends two different types of HAZID methods: the function-driven and component-driven approach. The BLHAZID method is based on a conceptual framework called the Functional Systems Framework, which describes structure–function–goal relationships in process systems.The goals of the BLHAZID methodology are to generate outcomes that contain a high coverage of hazards, describe detailed failure causality in process systems and express this knowledge in a structured form for effective reused in subsequent applications, such as fault diagnosis, operator training, design reviews, fault and event tree construction and hazard updates to satisfy major hazard facility requirements.Both the BLHAZID methodology and the Functional Systems Framework were developed with involvement and advice from two major industrial partners. An industrial case study of a benzene saturation unit is presented to illustrate how the BLHAZID methodology operates in practice. 相似文献