Assessing and Modeling Landscape Change in a Sensitive High-Elevation Region of the Bolivian Andes

This study used remotely sensed land cover and topographic data, maximum likelihood classification, and spectral mixing analysis to characterize current landscape patterns and quantify land cover change from 1985 to 2003 in the Southeastern Bolivian Andes. Current land cover was mapped into 9 classes with an overall accuracy of 89%. The change analysis demonstrated significant gains in bare and cultivated land (4.4% and 4.1%, respectively) at the expense of forest and pasture (losses of 4.8% and 3.9%, respectively). Spectral mixture analysis indicated that communal rangeland degradation (as measured by changes in proportions of green vegetation, non-photosynthetic vegetation and bare soil on the landscape) may have occurred, especially where conversion of land to more productive uses is restricted by soil fertility, topography, and climate. The study demonstrated that remotely sensed data and traditional image analysis techniques can be used to characterize land cover and land cover change in remote, mountainous areas

Mechanical Harvesting Effectively Controls Young Typha spp. Invasion and Unmanned Aerial Vehicle Data Enhances Post-treatment Monitoring

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

Demonstration of surface electron rejection with interleaved germanium detectors for dark matter searches

The following article appeared in Applied Physics Letters 103.16 (2013): 164105 and may be found at http://scitation.aip.org/content/aip/journal/apl/100/26/10.1063/1.4729825The SuperCDMS experiment in the Soudan Underground Laboratory searches for dark matter with a 9-kg array of cryogenic germanium detectors. Symmetric sensors on opposite sides measure both charge and phonons from each particle interaction, providing excellent discrimination between electron and nuclear recoils, and between surface and interior events. Surface event rejection capabilities were tested with two 210 Pb sources producing ∼130 beta decays/hr. In ∼800 live hours, no events leaked into the 8–115 keV signal region, giving upper limit leakage fraction 1.7 × 10−5 at 90% C.L., corresponding to < 0.6 surface event background in the future 200-kg SuperCDMS SNOLAB experiment.This work is supported in part by the National Science Foundation (Grant Nos. AST-9978911, NSF-0847342, PHY-1102795,NSF-1151869, PHY-0542066, PHY-0503729, PHY-0503629, PHY-0503641, PHY-0504224, PHY-0705052,PHY-0801708, PHY-0801712, PHY-0802575, PHY-0847342, PHY-0855299, PHY-0855525, and PHY-1205898), by the Department of Energy (Contract Nos. DE-AC03-76SF00098, DE-FG02-92ER40701, DE-FG02-94ER40823,DE-FG03-90ER40569, DE-FG03-91ER40618, and DESC0004022),by NSERC Canada (Grant Nos. SAPIN 341314 and SAPPJ 386399), and by MULTIDARK CSD2009-00064 and FPA2012-34694. Fermilab is operated by Fermi Research Alliance, LLC under Contract No. De-AC02-07CH11359, while SLAC is operated under Contract No. DE-AC02-76SF00515 with the United States Department of Energy

A Global Systematic Review of Empirical Evidence of Ecotourism Impacts on Forests in Biodiversity Hotspots

Ecotourism is growing rapidly in biodiversity hotspots because of its promise to achieve both economic growth and environmental conservation. We reviewed the literature for empirical evidence that ecotourism protects forests. Our conclusions are at once both sobering and encouraging. Ecotourism, as it is typically practiced, leads to deforestation. However, when accompanied by conservation mechanisms (e.g. protected area, Payment for Ecosystem Services, monitoring/enforcement), ecotourism can protect forests. Ecotourism sometimes leads to forest regeneration in agrarian landscapes, but trade-offs, for example old-growth deforestation or water pollution, may occur. From a methodological perspective, we found a dearth (only 17) of articles that empirically analyzed ecotourism impacts on forests, and no studies that used counterfactual impact evaluation approaches. We conclude that there is an insufficient evidence base for inferring effects of ecotourism on forests, and we identify research priorities to build knowledge about how, when, and where to implement ecotourism

Deforestation and Timber Production in Congo After Implementation of Sustainable Forest Management Policy

Over 400 million hectares of tropical forests are managed for timber production, comprising more than half of the remaining global permanent tropical forest estate. A growing proportion of tropical production forests are managed under Sustainable Forest Management (SFM) principles. The objective of SFM is to achieve multiple benefits, including forest protection, biodiversity conservation and income enhancement. However, the outcomes resulting from the implementation of SFM in tropical forest ecosystems have seldom been examined rigorously. In this paper, we present a methodological approach to assess broad-scale impacts of SFM policy in tropical forest ecosystems. As a case study, we investigated deforestation and timber production in logging concessions in the Republic of Congo after the implementation of its SFM-based forestry law in 2000. Compliance with the forestry law was incomplete, allowing a unique opportunity to compare deforestation and legal timber production outcomes in concessions that implemented SFM-based policy compared to those that did not. Quasi-experimental matching analysis indicated that deforestation in matched parcels in compliant concessions was up to 2-times higher than matched parcels in non-compliant concessions, equivalent to 67 km2 of forest loss for the period 2005–2010. Annual deforestation data demonstrated that deforestation was stable or increased in all six concessions following the respective date of compliance in each concession. Legal timber production increased (by 5%, from 0.18 to 0.19 CBM/ha/yr) and became more stable, in compliant compared to non-compliant concessions. Our results suggest that the presence of SFM in a concession does not immediately lead to less deforestation. Rather, SFM policy may be associated with higher deforestation, because SFM is also associated with higher legal timber production, foreign capital, and international timber demand. Our findings measure short-term associations between SFM and deforestation in the Congo, and underscore the need for empirical evaluation of long-term impacts of SFM in tropical forest ecosystems worldwide

Deforestation and Timber Production in Congo After Implementation of Sustainable Management Policy: A Response to Karsenty et al. (2017)

The outcomes of forest management (FM) as implemented by industrial logging corporations in tropical forests is an issue that merits greater scrutiny than it has received thus far. We, therefore, welcome the contribution by Karsenty et al. (2017) that questions some of the findings advanced in our article (Brandt et al., 2016). Our paper used satellite-derived deforestation data and statistical matching techniques to examine patterns of deforestation and timber production in the Republic of Congo after the implementation of FM plans in timber concessions. We found that a) deforestation rates were higher in concessions that had a registered forest management plan (FMP) compared to those that did not ; b) deforestation rates increased after a concession adopted a FMP; and c) timber production was higher and more stable in concessions that adopted a FMP than in concessions that did not. In their response, Karsenty et al. (2017) question our analytical approach and advocate for different evaluative criteria. While their response offers new and potentially valuable perspectives, it also criticizes our paper for errors our paper does not contain, and suggests we should have carried out analyses that we already did. In this rejoinder, we discuss the extent to which we consider their arguments relevant, valid, and worthy of further study. We note that neither Karsenty et al. (2017), nor any other peer-reviewed article that we know of, provide empirical results that contradict the findings of our original article

Mesic Vegetation Persistence: A New Approach for Monitoring Spatial and Temporal Changes in Water Availability in Dryland Regions Using Cloud Computing and the Sentinel and Landsat Constellations

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\u27s 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

Foreign capital, forest change and regulatory compliance in Congo Basin forests

Tropical forest change is driven by demand in distant markets. Equally, investments in tropical forest landscapes by capital originating from distant emerging economies are on the rise. Understanding how forest outcomes vary by investment source is therefore becoming increasingly important. We empirically evaluate the relationship between investment source and deforestation from 2000 to 2010 in the Republic of Congo. A Congolese forestry code was implemented in 2000 to mitigate degradation of production forests by standardizing all logging in the country according to sustainable forest management (SFM) guidelines. Following the implementation of this law, the majority (73%) of Congo’s production forests were managed by European (40%) and Asian (33%) companies. European concessions had the highest rates of total and core deforestation, followed by Asian concessions, indicating that the fragmentation of intact forests in Congo is strongly associated with industrial logging fueled by foreign capital. European concession holders were also far more likely to comply with SFM policies, followed by Asian concessions, suggesting that compliance with Sustainable Forest Management policies may not mitigate degradation in tropical production forests. Further evaluation of the relationship between investment source, regulatory compliance, and outcomes in tropical countries is essential for effective conservation of tropical forest ecosystems