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Cavity ring-down spectroscopy (CRDS) has allowed for increasingly widespread, in situ observations of trace gases, including the stable isotopic composition of water vapor. However, gathering observations in harsh environments still poses challenges, particularly in regard to observing the small-scale exchanges taking place between the surface and atmosphere. It is especially important to resolve the vertical structure of these processes. We have designed the ISE-CUBE system as a modular CRDS deployment system for profiling stable water isotopes in the surface layer, specifically the lowermost 2 m above the surface. We tested the system during a 2-week field campaign during February–March 2020 in Ny-Ålesund, Svalbard, Norway, with ambient temperatures down to -30 ∘ C. The system functioned suitably throughout the campaign, with field periods exhibiting only a marginal increase in isotopic measurement uncertainty (30 %) as compared to optimal laboratory operation. Over the 2 m profiling range, we have been able to measure and resolve gradients on the temporal and spatial scales needed in an Arctic environment. [ABSTRACT FROM AUTHOR]

Over the last two decades, cavity ring-down spectroscopy (CRDS) has allowed for increasingly widespread, in-situ observations of trace gases in vapor, including the stable isotopic composition of water vapor. However, in-situ observation in harsh environments pose a particular challenge, as these CRDS analyzers are designed for use in a conventional laboratory. As such, field deployments typically enclose the instrument in a "quasi-laboratory". These deployments often involve substantial logistical effort, 5 in addition to potentially affecting the measurement site, such as impacting flow conditions around near-surface processes. We designed the ISE-CUBE system as a modular CRDS deployment system for stable water isotope measurements, with a specific focus on observing near-surface processes. We tested the system during a two-week field campaign during Feb-March 2020 in Ny-Ålesund, Svalbard, Norway, with ambient temperatures down to -30 C, and winds gusting over 20ms-1. The system functioned suitably throughout the campaign, with field periods exhibiting only a minimal decrease in isotopic 10 measurement precision (18O: 0.06? & D: 0.47?) as compared to optimal laboratory operation. Having proven itself in challenging arctic conditions, the ISE-CUBE system can be readily adapted to the particular needs of future stable water isotope researchers, wherever their research aims might take them. [ABSTRACT FROM AUTHOR]

The Bonn Challenge, a global effort to begin restoring 350 million hectares of degraded forest landscapes by 2030, was launched in 2011. To date countries have committed to restore more than 60 million hectares as part of the Bonn Challenge. As global decision-makers, governments, and communities join the effort to restore degraded land, new questions about the economics of restoration have emerged. Critics argue that restoration takes too long, costs too much, and produces too few benefits to justify public or private expenditures. This paper addresses these concerns by presenting a methodology for valuing the net benefits of large-scale ecosystem restoration initiatives by estimating the net benefit of achieving the Bonn Challenge. This paper also estimates the net benefit of achieving the Bonn Challenge restoration target under different social discounting regimes, different valuations of public goods, and different time horizons to see how they affect the argument for investing society's scarce resources in restoration. The results suggest that achieving the Bonn Challenge would generate a net benefit of between U.S.$0.7 and U.S.$9 trillion. The results show that restoration can create benefits that exceed its costs and that the value of these benefits might differ depending on the discount rate. The results show that lower social discount rates correspond to higher restoration rates. This suggests that the Bonn Challenge target is more likely to be met when a low social discount rate is used to discount the benefits and costs of restoration. [ABSTRACT FROM AUTHOR]

The conversion of ranch open space to development uses is common in rural areas experiencing rapid growth, often due to in-migration. There is concern that a growing and changing population could alter community preferences regarding development, permanently changing the physical and social landscape. This study investigates the nonmarket value of ranch open space to residents of an amenity-rich county in the Rocky Mountains (USA) using survey data from 1994 and 2004. We find that on that, on average, there was no difference in what residents were willing to pay for ranch open space conservation between the two years, and that income has a positive effect on willingness to pay. Because the population of the county is growing and average willingness to pay has stayed constant, aggregate willingness to pay for public ranch open space has increased, leading to greater total social benefits of public conservation initiatives. [ABSTRACT FROM AUTHOR]

Abstract: Ecological tourism has held up as a potentially important development alternative in relatively undeveloped regions and countries. However, tourism is a highly vulnerable activity where tourists display voluntary and discretionary behavior. While tourism can serve as an income-generating activity for the region, uncontrolled tourism that is developed without consideration of the environmental impact can adversely affect the natural areas. Determining what to charge tourists to view a natural area is difficult since demand elasticities are not readily available from observable transactions. In order to better gauge the value tourists place on the reserve and their sensitivity to changes in the costs of visiting Eduardo Avaroa, non-market valuation provides several valuable tools. Here, we test the convergent validity between two popular non-market valuation alternatives: the contingent valuation method and the contingent behavior method. Tourists to the Eduardo Avaroa Reserve in Bolivia were asked their willingness to pay (in visitor-days or in dollars) due to an improvement in tourism services at the reserve. Our models show that the traditionally important variables predict willingness to pay for improved services for the contingent behavior, contingent valuation and the pooled model. However, we find statistically and empirically meaningful distinctions in the estimates derived from the two methods. Comparisons of the implications of adopting the entrance fee recommendations from the two non-market valuation techniques are made based on the revenues predicted to accrue to Eduardo Avaroa Reserve if park management techniques were improved. This research highlights the challenges in using non-market valuation techniques for policy formation, particularly in a developing country setting. [Copyright &y& Elsevier]

Explores the potential economic impact of chronic wasting disease (CWD) in Colorado. Lack of direct information on the economic aspects of CWD; Factors that make it difficult to measure the economic impact of CWD; Economic information resources that can be used to extract data on the economic impact of CWD on the state.

Public land designations are often primarily political decisions that may also have substantial local economic impacts. This paper econometrically estimates the visitation effect of the conversion of National Monuments to National Parks through the eight designation changes that have occurred between 1979 and 2000. The study finds robust and significant impacts of such conversions, yielding 11,642 additional visitors annually, even after controlling for likely site acreage expansion and other site visitation trends. Furthermore, these new visitors do not appear to occur at the expense of visitation at alternative sites. Using these findings, the paper explores the local economic impact of the Great Sand Dunes conversion on Colorado's San Luis Valley. [ABSTRACT FROM AUTHOR]

Recreational fishing value of the Brazilian Pantanal is measured using travel cost method (TCM). We compare non-linear, Poisson and negative binomial count data models to estimate recreational fishing trip demands. The count data and truncated models are used primarily to account for non-negative integer and truncation properties of recreational fishing trips as suggested by the recreation valuation literature. The results reveal that non-linear and truncated count data models perform relatively well in our study. The economic values of recreational fishing in terms of consumer surplus (CS) are derived using non-linear and truncated models. We estimate the CS values from $540.54 to $869.57 per trip resulting in the total social welfare estimate range from $35 to $56 million. The study demonstrates a relatively high value of recreational fishing in the Pantanal in comparison to similar studies conducted in other parts of the world. The findings of this study would be important for resource management decisions in the Pantanal and could serve as a reference in valuing similar resources in other ecosystems around the world. [Copyright &y& Elsevier]

There are critical knowledge gaps in non-equilibrium (kinetic) fractionation during cold and dry conditions. It is the aim of this work to thoroughly investigate stable water isotope fractionation under conditions associated with Cold-Air Outbreaks (cold and dry), focusing on diffusion fractionation factors and their dependency on temperature and humidity. This includes reevaluating previously estimated diffusion fractionation factors, with the goal of reinterpreting secondary isotope parameters (d-excess and 17O-excess) as evaporation condition tracers. By making measurements in the lab and field, the current knowledge gap will be filled with empirical evidence.Here we present a setup to acquire measurements from the field, under conditions comparable to those in previous laboratory studies. These field measurements will be made using novel measurement techniques and cutting-edge instrumentation. This includes the design and construction of a new field deployment apparatus: a rugged, modular system with a stable water isotope analyzer at its heart. It must be designed to withstand harsh Arctic conditions, while still facilitating transportation, installation, and use. Additionally, the system must allow for expansion and interaction with other components necessary to the success of our future field campaigns. Through this construction, we endeavor to reduce our field deployment siting limitations, and ensure that the data obtained in the field will be of high-quality. Ultimately, this data collection will put us closer to our goal of refining the interpretation of d-excess and 17O-excess as tracers for atmospheric water's source. [ABSTRACT FROM AUTHOR]

​​​​​​​Here we describe a versatile device to produce a gas stream with a precisely controlled water vapour mixing ratio and stable water isotope composition based on microdrop dispensing technology. To produce a moist airstream, the microdrop dispensing technology ejects micrometre-size water droplets that completely evaporate into a stream of carrier gas heated to 60 ∘ C. By precisely controlling the contribution of water standards from two dispenser heads into a carrier gas stream, the device allows one to set the air–vapour stream to any isotope ratio between two endmember waters. We show that the Allan deviation of the water vapour mixing ratio is 10 ppmv over more than 24 h and reaches 0.004 ‰ for δ18 O and 0.02 ‰ for δ2 H for a flow rate of 40 sccm. Tests with flow rates from 40–250 sccm show an increase of the Allan deviation with higher flow rates. Tests with mixing standard water from two dispenser heads show a linear mixing across a range of water vapour mixing ratios from 1000 to 20 000 ppmv. In addition to presenting the design and several performance characteristics of the new system, we describe two application examples. First, we utilise the device to determine the water vapour mixing ratio–isotope ratio dependency, a common artefact of water vapour isotope spectrometers. Second, we utilise the device to provide a constant background stream of moist air for fluid inclusion water isotope analysis in calcite samples from stalagmites. The observed flexibility and precision of the device underpins its usefulness and potential for a wide range of applications in atmospheric water vapour isotope measurements. Future developments could focus on reducing the number of manual interventions needed to clear dispenser heads from gas bubbles and the provision of a water vapour stream at flow rates of up to several litres per minute. [ABSTRACT FROM AUTHOR]

Our planet is facing increasing challenges: climate change, biodiversity loss, pandemics, poverty, and many other problems closely linked to a deteriorating environment. Meanwhile, one of our most important assets, rangers working in protected and conserved areas responsible for managing large tracts of the planet's lands and waters, are often underutilized, underrecognized and underequipped. They are generally left out of the debate about conservation and sustainable development policy, despite being central to the success of those policies. This paper outlines the need for global leaders across multiple sectors to recognize the profession of rangers as essential planetary health workers and to position rangers more effectively within global conservation and environmental policy mechanisms. It introduces the challenges facing rangers, the emerging diversity of roles within the ranger profession and the important contribution of rangers to conservation and sustainable development. It presents policy and implementation avenues to improve recognition and professionalization of rangers as key executors of conservation and development policy, particularly considering the recent Global Biodiversity Framework ambitions. [ABSTRACT FROM AUTHOR]

Many developing rural economies depend on natural capital stocks for generating income and wealth. However, common property natural resources are often over-exploited. One method of solving over-exploitation is privatisation of the resource. In Palena, Chile, the privatisation of common-property grazing land facilitated a change in land use from grazing to tourism activities. We present a theoretical model that demonstrates that privatisation that leads to land use change has the potential to increase local wages. To resolve theoretical ambiguities, we calibrate a local general equilibrium model and find that privatisation and a switch to tourism resulted in higher wages in the local economy of Palena. This finding contributes to the ongoing investigation of the local costs and benefits of resource privatisation in developing countries. [ABSTRACT FROM AUTHOR]

Here we describe a versatile device to produce a flow of air-vapour mixture with controlled humidity and water isotope composition based on microdrop dispensing technology. By precisely controlling the contribution of water from two dispenser heads into a carrier gas stream, the device allows to set the air-vapour stream to any isotope ratio between two end member waters. In addition to presenting the design and several performance characteristics of the new system, we describe two application examples. First, we utilize the device to determine a common artifact of vapour isotope analyzers, known as the mixing ratio - isotope ratio dependency. Second, we utilize the device to provide a constant background stream of humid air for fluid inclusion water isotope analysis in stalagmites. The observed flexibility and precision of the device underpints its usefulness and potential for a wide range of applications in atmospheric water vapour isotope measurement applications. Future improvements could focus on reducing the number of manual interventions and improved control at high flow rates. [ABSTRACT FROM AUTHOR]

Protected areas are key to the conservation of global biodiversity and ecosystem services; however, their success is contingent upon adequate funding. One possibility to increase funding for park management is to “sell” a wider suite of ecosystem services “produced” by protected areas, such as carbon sequestration. We conducted 420 tourist surveys to analyze willingness to pay (WTP) for ecosystem service benefits via a conservation fee in the Tambopata National Reserve in Peru. We also interviewed eight tour operators about their perceptions of the proposed fee. The average stated WTP was 15 USD. Sixty-six percent of tourists stated they would pay 10 USD or more, which, if actually paid, would have resulted in 318,000 USD for park management in 2015. Most respondents stated they would pay an additional fee if it supported biodiversity conservation or local ecosystem services, such as water, but less than 10% of tourists were motivated by carbon sequestration as a reason to pay the fee. Most tour operators supported the additional fee. Our findings suggest that tourists are willing to pay higher fees to support conservation but that interest in paying for additional ecosystem services from parks may not extend to global and intangible benefits such as carbon sequestration. [ABSTRACT FROM PUBLISHER]

Laser active remote sensing of tropospheric water vapor is a promising technology to complement passive observational means in order to enhance our understanding of processes governing the global hydrological cycle. In such a context, we investigate the potential of monitoring both water vapor H216O and its isotopologue HD16O using a differential absorption lidar (DIAL) allowing for ground-based remote measurements at high spatio-temporal resolution (150 m and 10 min) in the lower troposphere. This paper presents a sensitivity analysis and an error budget for a DIAL system under development which will operate in the 2 µm spectral region. Using a performance simulator, the sensitivity of the DIAL-retrieved mixing ratios to instrument-specific and environmental parameters is investigated. This numerical study uses different atmospheric conditions ranging from tropical to polar latitudes with realistic aerosol loads. Our simulations show that the measurement of the main isotopologue H216O is possible over the first 1.5 km of atmosphere with a relative precision in the water vapor mixing ratio of <1 % in a mid-latitude or tropical environment. For the measurement of HD16O mixing ratios under the same conditions, relative precision is found to be slightly lower but still sufficient for the retrieval of range-resolved isotopic ratios with precisions in δD of a few per mil. We also show that expected precisions vary by an order of magnitude between tropical and polar conditions, the latter giving rise to poorer sensitivity due to low water vapor content and low aerosol load. Such values have been obtained for a commercial InGaAs PIN photodiode, as well as for temporal and line-of-sight resolutions of 10 min and 150 m, respectively. Additionally, using vertical isotopologue profiles derived from a previous field campaign, precision estimates for the HD16O isotopic abundance are provided for that specific case. [ABSTRACT FROM AUTHOR]

This article discusses major conservation program provisions of the U.S. farm bill and implications for future funding for working lands programs. The relative increase in the importance of conservation over 2002 is highlighted. The article also explores the evolution of U.S. conservation programs and provides an outline of conservation provisions in the 2008 farm bill.

Laser active remote sensing of tropospheric water vapor is a promising technology to complement passive observational means in order to enhance our understanding of processes governing the global hydrological cycle. In such context, we investigate the potential of monitoring both water vapor H216O and its isotopologue HD16O using a differential absorption lidar (DIAL) allowing for ground-based remote measurements at high spatio-temporal resolution (150 m and 10 min) in the lower troposphere. This paper presents a sensitivity analysis and an error budget for a DIAL system under development which will operate in the two-micron spectral region. This numerical study uses different atmospheric conditions ranging from tropical to polar latitudes with realistic aerosol loads. Our simulations show that the measurement of the main isotopologue H216O is possible over the first 1.5 km of atmosphere with a relative precision in the water vapor mixing ratio of < 1 % in a mid-latitude or tropical environment. For the measurement of HD16O mixing ratios under the same conditions, relative precision is shown to be of similar order, thus allowing for the retrieval of range-resolved isotopic ratios. We also show that expected precisions vary by an order of magnitude between tropical and polar conditions, the latter giving rise to reduced precision due to low water vapor content and low aerosol load. Such values have been obtained for a commercial InGaAs PIN photodiode, as well as temporal and line-of-sight resolutions of 10 min and 150 m, respectively. Additionally, using vertical isotopologue profiles derived from a previous field campaign, precision estimates for the HD16O isotopic abundance are provided. [ABSTRACT FROM AUTHOR]

Abstract: The economic valuation of coral reefs ecosystem services is currently seen as a promising approach to demonstrate the benefits of sustainable management of coral ecosystems to policymakers and to provide useful information for improved decisions. Most coral reefs economic studies have been conducted in the United States, Southeast Asia and the Caribbean, and only a few have covered the South Pacific region. In this region, coral reefs are essential assets for small island developing states as well as for developed countries. Accordingly, a series of ecosystem services valuations has been carried out recently in the South Pacific, to try and supply decision-makers with new information. Applying ecosystem services valuation to the specific ecological, social, economic and cultural contexts of the South Pacific is however not straightforward. This paper analyses how extant valuations address the various management challenges of coral reef regions in general and more specifically for the South Pacific. Bearing in mind that economic valuation has to match policy-making contexts, we emphasize a series of specific considerations when conducting and applying ecosystem services valuation in South Pacific ecological and social contexts. Finally, the paper examines the decision-making situations in which extant valuations took place. We conclude that, although ecosystem valuations have been effectively used as a means to raise awareness with respect to coral reef conservation, methodologies will have to be further developed, with multidisciplinary inputs, if they are to provide valuable inputs in local and technical decision-making. [Copyright &y& Elsevier]

The aim of the research project “Innovative Strategies for Observations in the Arctic Atmospheric Boundary Layer (ISOBAR)” is to substantially increase the understanding of the stable atmospheric boundary layer (SBL) through a combination of well-established and innovative observation methods as well as by models of different complexity. During three weeks in February 2017, a first field campaign was carried out over the sea ice of the Bothnian Bay in the vicinity of the Finnish island of Hailuoto. Observations were based on ground-based eddy-covariance (EC), automatic weather stations (AWS) and remote-sensing instrumentation as well as more than 150 flight missions by several different Unmanned Aerial Vehicles (UAVs) during mostly stable and very stable boundary layer conditions. The structure of the atmospheric boundary layer (ABL) and above could be resolved at a very high vertical resolution, especially close to the ground, by combining surface-based measurements with UAV observations, i.e., multicopter and fixed-wing profiles up to 200 m agl and 1800 m agl, respectively. Repeated multicopter profiles provided detailed information on the evolution of the SBL, in addition to the continuous SODAR and LIDAR wind measurements. The paper describes the campaign and the potential of the collected data set for future SBL research and focuses on both the UAV operations and the benefits of complementing established measurement methods by UAV measurements to enable SBL observations at an unprecedented spatial and temporal resolution. [ABSTRACT FROM AUTHOR]