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Climate change and anthropogenic activity pose severe threats to water availability in drylands. A better understanding of water availability response to these threats could improve our ability to adapt and mitigate climate and anthropogenic effects. Here, we present a Mesic Vegetation Persistence (MVP) workflow that takes every usable image in the Sentinel (10-m) and Landsat (30-m) archives to generate a dense time-series of water availability that is continuously updated as new images become available in Google Earth Engine. MVP takes advantage of the fact that mesic vegetation can be used as a proxy of available water in drylands. Our MVP workflow combines a novel moisture-based index (moisture change index - MCI) with a vegetation index (Modified Chlorophyll Absorption Ratio Vegetation Index (MCARI2)). MCI is the difference in soil moisture condition between an individual pixel's state and the dry and wet reference reflectance in the image, derived using 5th and 95th percentiles of the visible and shortwave infra-red drought index (VSDI). We produced and validated our MVP products across drylands of the western U.S., covering a broad range of elevation, land use, and ecoregions. MVP outperforms NDVI, a commonly-employed index for mesic ecosystem health, in both rangeland and forested ecosystems, and in mesic habitats with particularly high and low vegetation cover. We applied our MVP product at case study sites and found that MVP more accurately characterizes differences in mesic persistence, late-season water availability, and restoration success compared to NDVI. MVP could be applied as an indicator of change in a variety of contexts to provide a greater understanding of how water availability changes as a result of climate and management. Our MVP product for the western U.S. is freely available within a Google Earth Engine Web App, and the MVP workflow is replicable for other dryland regions.
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Predicting forest recovery at landscape scales will aid forest restoration efforts. The first step in successful forest recovery is tree recruitment. Forecasts of tree recruit abundance, derived from the landscape-scale distribution of seed sources (i.e., adult trees), could assist efforts to identify sites with high potential for natural regeneration. However, previous work revealed wide variation in the effect of seed sources on seedling abundance, from positive to no effect. We quantified the relationship between adult tree seed sources and tree recruits and predicted where natural recruitment would occur in a fragmented, tropical, agricultural landscape. We integrated species-specific tree crown maps generated from hyperspectral imagery and property ownership data with field data on the spatial distribution of tree recruits from five species. We then developed hierarchical Bayesian models to predict landscape-scale recruit abundance. Our models revealed that species-specific maps of tree crowns improved recruit abundance predictions. Conspecific crown area had a much stronger impact on recruitment abundance (8.00% increase in recruit abundance when conspecific tree density increases from zero to one tree; 95% credible interval (CI): 0.80% to 11.57%) than heterospecific crown area (0.03% increase with the addition of a single heterospecific tree, 95% CI: -0.60% to 0.68%). Individual property ownership was also an important predictor of recruit abundance: The best performing model had varying effects of conspecific and heterospecific crown area on recruit abundance, depending on individual property ownership. We demonstrate how novel remote sensing approaches and cadastral data can be used to generate high-resolution and landscape-level maps of tree recruit abundance. Spatial models parameterized with field, cadastral, and remote sensing data are poised to assist decision support for forest landscape restoration.
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Bosques , Semillas , Teorema de Bayes , Plantones , Especificidad de la Especie , Clima TropicalRESUMEN
Conservation easements are the fastest growing private conservation strategy in the United States. However, mechanisms to assess private land conservation as well as their support by the general public are not well understood. This study uses the ecosystem services framework for assessing existing private lands in Idaho and identifies areas for future conservation easements. Using conservation targets of the land trust as a guide for selecting ecosystem services, we (a) mapped the spatial delivery of conservation targets across public and private lands, (b) explored public awareness in terms of social importance and vulnerability, and (c) mapped future priority areas by characterizing conservation bundles. We found that public lands provided the highest levels of conservation targets, and we found no difference in conservation target provision between private areas and conservation easements. The spatial characterization of conservation target bundles identified potential future priority areas for conservation easements, which can guide planning of land trust conservation efforts.
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Conservación de los Recursos Naturales , Ecosistema , Estados UnidosRESUMEN
Roads are proliferating worldwide at an unprecedented rate, with potentially severe impacts on wildlife. We calculated the extent and potential impacts of road networks across the 1,160,000-km2, 13-country range of the globally endangered tiger (Panthera tigris)-a conservation umbrella species. We found that roads were pervasive, totaling 134,000 km across tiger conservation landscapes (TCLs), even in tiger priority sites and protected areas. Approximately 43% of the area where tiger breeding occurs and 57% of the area in TCLs fell within the road-effect zone. Consequently, current road networks may be decreasing tiger and prey abundances by more than 20%. Nearly 24,000 km of new roads will be built in TCLs by 2050, stimulated through major investment projects such as China's Belt and Road Initiative. Given that roads will be a pervasive challenge to tiger recovery in the future, we urge decision-makers to make sustainable road development a top priority.
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Background: Canada was the first country to approve elbasvir/grazoprevir (EBR/GZR) for the treatment of chronic HCV infection for genotypes 1 and 4 with or without ribavirin and genotype 3 with sofosbuvir, with no recommendation for baseline resistance testing. The aim of this study was to describe the effectiveness of EBR/GZR and the profile of patients selected for treatment in a Canadian real-world setting. Methods: This multicenter retrospective study of HCV-infected patients treated with EBR/GZR took place among selected Canadian health care providers, with no exclusion criteria. Primary outcome measures included parameters associated with patient profile and sustained virologic response at 12 weeks (SVR12) and 24 weeks after treatment. Results: A total of 408 patients were included; 244 had available SVR12 information (per-protocol population [PP]). Genotype distribution included 1a (54.7%), 1b (17.2%), 3 (11.8%), 4 (10.0%), and other (6.4%). The majority (88.7%) of participants were treated for 12 weeks without ribavirin. Fifty-nine (14.5%) participants, predominantly with genotype 1a (49/59) infection, were tested for baseline resistance-associated substitutions (bRAS). SVR12 was achieved by 95.9% of the PP. In an exploratory analysis assessing potential predictors of SVR12, participants who had undergone bRAS testing (OR 0.14, 95% CI 0.03-0.64) and participants who had undergone liver transplant (OR 0.05, 95% CI 0.00-0.68) had significantly lower odds of achieving SVR12. Conclusions: This study supports the real-world effectiveness of EBR/GZR-including a broad range of genotypes and diverse fibrosis stages-in the absence of bRAS testing and in special populations.
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Reducing emissions from deforestation and forest degradation (REDD+) is a climate change mitigation policy in which rich countries provide payments to developing countries for protecting their forests. In 2009, the countries of Norway and Guyana entered into one of the first bilateral REDD+ programs, with Norway offering to pay US$250 million to Guyana if annual deforestation rates remained below 0.056% from 2010 to 2015. To quantify the impact of this national REDD+ program, we construct a counterfactual times-series trajectory of annual tree cover loss using synthetic matching. This analytical approach allows us to quantify tree cover loss that would have occurred in the absence of the Norway-Guyana REDD+ program. We found that the Norway-Guyana REDD+ program reduced tree cover loss by 35% during the implementation period (2010 to 2015), equivalent to 12.8 million tons of avoided CO2 emissions. Our analysis indicates that national REDD+ payments attenuated the effect of increases in gold prices, an internationally traded commodity that is the primary deforestation driver in Guyana. Overall, we found strong evidence that the program met the additionality criteria of REDD+. However, we found that tree cover loss increased after the payments ended, and therefore, our results suggest that without continued payments, forest protection is not guaranteed. On the issue of leakage, which is complex and difficult to quantify, a multinational REDD+ program for a region could address leakage that results from differences in forest policies between neighboring countries.
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Conservación de los Recursos Naturales/métodos , Modelos Teóricos , Árboles , Conservación de los Recursos Naturales/estadística & datos numéricos , Política Ambiental , Bosques , Guyana , Cooperación Internacional , NoruegaRESUMEN
Ecotourism is developing rapidly in biodiversity hotspots worldwide, but there is limited and mixed empirical evidence that ecotourism achieves positive biodiversity outcomes. We assessed whether ecotourism influenced forest loss rates and trajectories from 2000 to 2017 in Himalayan temperate forests. We compared forest loss in 15 ecotourism hubs with nonecotourism areas in 4 Himalayan countries. We used matching statistics to control for local-level determinants of forest loss, for example, population density, market access, and topography. None of the ecotourism hubs was free of forest loss, and we found limited evidence that forest-loss trajectories in ecotourism hubs were different from those in nonecotourism areas. In Nepal and Bhutan, differences in forest loss rates between ecotourism hubs and matched nonecotourism areas did not differ significantly, and the magnitude of the estimated effect was small. In India, where overall forest loss rates were the lowest of any country in our analysis, forest loss rates were higher in ecotourism hubs than in matched nonecotourism areas. In contrast, in China, where overall forest loss rates were highest, forest loss rates were lower in ecotourism hubs than where there was no ecotourism. Our results suggest that the success of ecotourism as a forest conservation strategy, as it is currently practiced in the Himalaya, is context dependent. In a region with high deforestation pressures, ecotourism may be a relatively environmentally friendly form of economic development relative to other development strategies. However, ecotourism may stimulate forest loss in regions where deforestation rates are low.
Efectos del Ecoturismo sobre la Pérdida de Bosques en el Punto Caliente de Biodiversidad en el Himalaya con base en Análisis Contrafactuales Resumen El ecoturismo está desarrollándose rápidamente en los puntos calientes de biodiversidad en todo el mundo, pero existe evidencia empírica mixta y limitada de los resultados positivos que se logran con el ecoturismo. Valoramos si el ecoturismo influyó sobre las tasas de pérdida forestal y sus trayectorias entre el 2000 y el 2017 en los bosques templados del Himalaya. Comparamos la pérdida forestal en quince focos ecoturísticos con la pérdida forestal en las áreas sin ecoturismo de cuatro países del Himalaya. Utilizamos estadística correspondiente para controlar las determinantes a nivel local de la pérdida del bosque, por ejemplo, la densidad poblacional, el acceso al mercado y la topografía. Ninguno de los focos ecoturísticos estaba libre de pérdida forestal, además de que encontramos evidencia limitada de que las trayectorias de la pérdida forestal en los focos ecoturísticos eran diferentes a las trayectorias en las áreas sin ecoturismo. En Nepal y en Bután, las diferencias en la pérdida forestal entre los focos ecoturísticos y las áreas sin ecoturismo correspondidas no difirieron significativamente y la magnitud del efecto estimado fue menor. En la India, donde las tasas generales de pérdida forestal fueron las más bajas de cualquier país en nuestro análisis, las tasas de pérdida forestal fueron más altas en los focos ecoturísticos que en las áreas sin ecoturismo correspondidas. Como contraste, en China, donde las tasas generales de pérdida forestal fueron más altas, las tasas de pérdida forestal fueron más bajas en los focos ecoturísticos que en donde no existe el ecoturismo. Nuestros resultados sugieren que el éxito del ecoturismo como estrategia de conservación del bosque, a como se práctica actualmente en el Himalaya, depende del contexto. En una región con presiones altas de deforestación, el ecoturismo puede ser una forma de desarrollo económico relativamente amigable con el ambiente comparado con otras estrategias de desarrollo. Sin embargo, el ecoturismo puede estimular la pérdida forestal en regiones en las que las tasas de deforestación son bajas.
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Conservación de los Recursos Naturales , Agricultura Forestal , Bután , Biodiversidad , China , Bosques , India , NepalRESUMEN
Background: As hepatitis C virus (HCV) treatment continues to evolve, there is an ongoing need to understand and optimize real-world disease management. The primary objective of the SIMPLE study was to describe the real-life management of genotype 1 (G1) HCV in Canada treated with boceprevir + pegylated interferon and ribavirin therapy. Methods: This was an observational, prospective cohort, multicentre, non-interventional study of patients with G1 HCV. A single cohort of adult patients were to be managed as per standard of care (SoC) and treated with 4 weeks of PegRBV dual therapy, followed by boceprevir + PegRBV for 24-44 weeks, with 24-weeks follow-up. Treatment compliance, health care resource utilization (HCRU), HCV viral load, and hematological adverse event (AE) data were collected. Results: This study enrolled 159 patients. All investigators were well educated on the Canadian consensus guidelines for HCV management but only a minority of patients were treated according to treatment guidelines. Viral response was achieved by >50% of patients by week 8 of therapy and in 50%-60% of tested patients during follow-up. An average of 17.9 HCRU visits were reported during the study period. The most commonly used resources were nursing visits for routine follow-up. Conclusions: Results from this real-world study suggest that most patients were not treated according to the product monograph. Further studies are required to determine how oral treatments fit into this paradigm and how these findings extrapolate to the current treatment model. This study can serve as a benchmark for future real-world treatment including heath care utilization analyses.
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In light of the ongoing environmental impacts of agriculture, understanding farmer adoption of sustainable management practices (SMPs) is an important priority. Relatively little work in agricultural adoption has explicitly examined the multilevel dynamics of adoption decision-making. Yet because many SMPs involve cooperative dilemmas-they are individually costly but provide group benefits-understanding the dynamics of both individual and group level behavioral change is critical. In this paper, we argue that cultural evolutionary theory is well suited to examining the emergence and spread of cooperative SMPs, and we illustrate this claim by applying a cultural multilevel selection (CMLS) framework to the adoption of SMPs on the part of winegrape growers in California, USA. Using survey data from over 800 winegrape growers in 3 regions, we estimate the individual-level costs and group-level benefits of 44 different SMPs. We then relate this to variation in their adoption within and between winegrape growing regions to characterize the scope for cultural group selection of the various practices. We also identify a number of mechanisms that might plausibly explain the observed patterns of variation, including various forms of cultural group selection. We highlight the added value of this perspective with respect to the established approaches and outline the data requirements for researchers to conduct similar studies in other settings. Our results underscore the potential for a cultural evolutionary perspective to shed light on the multiscale mechanisms driving adoption of SMPs and, more generally, the promise of cultural evolutionary approaches to supplement existing analytical toolkits in sustainability science.
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The ecological impacts of invasive plants increase dramatically with time since invasion. Targeting young populations for treatment is therefore an economically and ecologically effective management approach, especially when linked to post-treatment monitoring to evaluate the efficacy of management. However, collecting detailed field-based post-treatment data is prohibitively expensive, typically resulting in inadequate documentation of the ecological effects of invasive plant management. Alternative approaches, such as remote detection with unmanned aerial vehicles (UAV), provide an opportunity to advance the science and practice of restoration ecology. In this study, we sought to determine the plant community response to different mechanical removal treatments to a dominant invasive wetland macrophyte (Typha spp.) along an age-gradient within a Great Lakes coastal wetland. We assessed the post-treatment responses with both intensive field vegetation and UAV data. Prior to treatment, the oldest Typha stands had the lowest plant diversity, lowest native sedge (Carex spp.) cover, and the greatest Typha cover. Following treatment, plots that were mechanically harvested below the surface of the water differed from unharvested control and above-water harvested plots for several plant community measures, including lower Typha dominance, lower native plant cover, and greater floating and submerged aquatic species cover. Repeated-measures analysis revealed that above-water cutting increased plant diversity and aquatic species cover across all ages, and maintained native Carex spp. cover in the youngest portions of Typha stands. UAV data revealed significant post-treatment differences in normalized difference vegetation index (NDVI) scores, blue band reflectance, and vegetation height, and these remotely collected measures corresponded to field observations. Our findings suggest that both mechanically harvesting the above-water biomass of young Typha stands and harvesting older stands below-water will promote overall native community resilience, and increase the abundance of the floating and submerged aquatic plant guilds, which are the most vulnerable to invasions by large macrophytes. UAV's provided fast and spatially expansive data compared to field monitoring, and effectively measured plant community structural responses to different treatments. Study results suggest pairing UAV flights with targeted field data collection to maximize the quality of post-restoration vegetation monitoring.
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Globally, deforestation continues, and although protected areas effectively protect forests, the majority of forests are not in protected areas. Thus, how effective are different management regimes to avoid deforestation in non-protected forests? We sought to assess the effectiveness of different national forest-management regimes to safeguard forests outside protected areas. We compared 2000-2014 deforestation rates across the temperate forests of 5 countries in the Himalaya (Bhutan, Nepal, China, India, and Myanmar) of which 13% are protected. We reviewed the literature to characterize forest management regimes in each country and conducted a quasi-experimental analysis to measure differences in deforestation of unprotected forests among countries and states in India. Countries varied in both overarching forest-management goals and specific tenure arrangements and policies for unprotected forests, from policies emphasizing economic development to those focused on forest conservation. Deforestation rates differed up to 1.4% between countries, even after accounting for local determinants of deforestation, such as human population density, market access, and topography. The highest deforestation rates were associated with forest policies aimed at maximizing profits and unstable tenure regimes. Deforestation in national forest-management regimes that emphasized conservation and community management were relatively low. In India results were consistent with the national-level results. We interpreted our results in the context of the broader literature on decentralized, community-based natural resource management, and our findings emphasize that the type and quality of community-based forestry programs and the degree to which they are oriented toward sustainable use rather than economic development are important for forest protection. Our cross-national results are consistent with results from site- and regional-scale studies that show forest-management regimes that ensure stable land tenure and integrate local-livelihood benefits with forest conservation result in the best forest outcomes.