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Author: Alex Pfaff

Reduction in exposure to arsenic from drinking well-water in Bangladesh limited by insufficient testing and awareness

Published September 6, 2017 by Alex Pfaff
Alexander Pfaff, Amy Schoenfeld, Kazi Matin Ahmed, Alexander van Geen
Journal of Water, Sanitation and Hygiene for Development 07.2 doi: 10.2166/washdev.2017.136

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This study considers potential policy responses to the still very high levels of exposure to arsenic (As) caused by drinking water from shallow tubewells in rural Bangladesh. It examines a survey of 4,109 households in 76 villages of Araihazar upazila conducted two years after a national testing campaign swept through the area. The area is adjacent to the region where a long-term study was initiated in 2000 and where households are periodically reminded of health risks associated with well-water elevated in As. Results confirm that testing spurs switching away from unsafe wells, although the 27% fraction who switched was only about half of that in the long-term study area. By village, the fraction of households that switched varied with the availability of safe wells and the distance from the long-term study area. Lacking follow-up testing, two years only after the campaign 21% of households did not know the status of their well and 21% of households with an unsafe well that switched did so to an untested well. Well testing is again urgently needed in Bangladesh and should be paired with better ways to raise awareness and the installation of additional deep community wells.

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Spillovers from Conservation Programs

Published September 6, 2017 by Alex Pfaff
Alexander Pfaff, Juan Robalino
Annual Review of Resource Economics 9:299-315

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Conservation programs have increased significantly, as has the evaluation of their impacts. However,the evaluation of their potential impacts beyond program borders has been scarce.Such spillovers can significantly reduce or increase net impacts. In this review, we discuss how conservation programs might affect outcomes beyond their borders and present some evidence of when they have or have not. We focus on five major channels by which spillovers can arise:(1) input reallocation; (2) market prices; (3) learning; (4) nonpecuniary motivations; and (5) ecological-physical links. We highlight evidence for each channel and emphasize that estimates often may reflect multiple channels. Future research could test for spillovers within different contexts and could separate the effects of different channels.

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Heterogeneous Local Spillovers from Protected Areas in Costa Rica

Published August 3, 2017 by Alex Pfaff
Juan Robalino, Alexander Pfaff, Laura Villalobos
JAERE, volume 4, number 3 http://dx.doi.org/10.1086/692089

Spillovers can significantly reduce or enhance the net effects of land-use policies, yet there exists little rigorous evidence concerning their magnitudes. We examine how Costa Rica’s national parks affect deforestation in nearby areas. We find that average deforestation spillovers are not significant in 0–5 km and 5–10 km rings around the parks. However, this average blends multiple effects that are significant and that vary in magnitude across the landscape, yielding varied net impacts. We distinguish the locations with different net spillovers by their distances to roads and park entrances — both of which are of economic importance, given critical local roles for transport costs and tourism. We find large and statistically significant leakage close to roads but far from park entrances, which are areas with high agricultural returns and less influenced by tourism. We do not find leakage far from roads (lower agriculture returns) or close to park entrances (higher tourism returns). Finally, parks facing greater threats of deforestation show greater leakage.

 

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Evolving Protected-Area Impacts in Mexico: Political Shifts as Suggested by Impact Evaluations

Published January 4, 2016 by Alex Pfaff
Alexander Pfaff, Franciso Santiago-Avila, Lucas Joppa
Forests 2017 8:17 doi:10.3390/f8010017

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For protected areas (PAs), variation in forest impacts over space—including types of PA—are increasingly well documented, while shifts in impacts over time receive less attention. For Mexico, in the 1990s, PAs effectively were ‘paper parks’. Thus, achieving impacts on the forest would require shifts over time in the politics of PA siting and PA implementation. We rigorously analyze the impacts of Mexican PAs on 2000–2005 loss of natural land cover, using matching to reduce location bias caused by typical land-use economics and politics. We find a 3.2% lower loss, on average, due to PAs. Since politics often vary by type of PA, we also show that in Mexico stricter PAs are closer to cities and have greater impact than mixed-use PAs. These shifts in impacts suggest some potential for PAs to conserve forests.

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Scaling up conservation impact in Madagascar

Published January 3, 2016 by Alex Pfaff
Theo Gimenez, Alexander Pfaff, Ranaivo Rasolofoson, Lucas Joppa
Draft working paper, Duke University.

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Ten years ago, Madagascar’s government committed to drastically scale up the nation’s protected-area coverage from ~3% to 10% of its area. We ask how successful this PA expansion is likely to be in terms of reducing deforestation (and, thereby, increasing the conservation of biodiversity). We statistically evaluate the impact of the prior generations of Malagasy PAs and use those results to anticipate the conservation impacts of Madagascar’s newest PAs. We find that deforestation was reduced by the prior PAs, although by less than suggested in simpler comparisons that lack explicit controls for land characteristics. Further, impacts are higher where deforestation pressure is higher, which often is closer to roads and cities (and which also may imply higher costs). We find Madagascar’s newest PAs are sited where, if managed correctly, they can achieve impacts at least as high as prior conservation.

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Deforestation dynamics in response to the evolution of the Western Amazonian Inter-Oceanic Highway

Published January 2, 2016 by Alex Pfaff
Cesar Delgado, Dalia Amor Conde, Joseph O. Sexton, Fernando Colchero, Jennifer J. Swenson, Alexander Pfaff
Draft working paper, Duke University.

 

Over the last three decades, the first continuous road has been paved to connect northern  South America’s Atlantic and Pacific coasts. The final sections of this Inter-Oceanic Highway are now being completed through the western Amazon Basin, a global biodiversity hotspot, at the triple-border of Brazil, Bolivia and Peru. Satellite images from 1989, 2000, and 2007 reveal accelerating clearing across the region, but the countries’ prior infrastructures governed their individual responses to the road. Brazilian deforestation slowed as the frontier expanded away from the highway with a network of capillary roads, but Bolivian clearing accelerated as its urban centers sprawled toward the road. Peru’s forests remain relatively intact, but similar trends isolated from Brazil suggest imminent acceleration as Peruvian infrastructural capacity increases.

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