238 research outputs found
Fast Radio Burst Tomography of the Unseen Universe
The discovery of Fast Radio Bursts (FRBs) at cosmological distances has
opened a powerful window on otherwise unseen matter in the Universe. In the
2020s, observations of FRBs will assess the baryon contents and
physical conditions in the hot/diffuse circumgalactic, intracluster, and
intergalactic medium, and test extant compact-object dark matter models.Comment: Science white paper submitted to the Astro2020 Decadal Survey. 15
pages, 3 color figure
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Analyzing procedural equity in government-led community-based forest management
Participatory approaches to forest management have been promoted as a means of returning rights historically removed, and as a way of managing natural resources sustainably, fairly, and to improve livelihoods in communities. Top-down models of community-based forest management take the perspective that if people feel ownership over, have a voice in decisions about, and can benefit from surrounding ecosystems, then they will be motivated to maintain and protect them. However, even participatory approaches, such as community-based forest management, may not always result in clear positive outcomes for involvement in decision making and forest conservation. We examine whether an Indonesian government initiative for community-based forest management was positively associated with community members' participation in local decision making and support for conservation and sustainable management of forest resources, in the context of state-owned lands. We used household questionnaire data to compare villages with and without a community forest, and community forests over time in a case study region of West Kalimantan. Analyzing forest visitations, conservation support, and indicators of procedural equity, we found no consistent association between having a community forest and higher levels of participation in decision making or household support for forest conservation. However, well-being indicators were positively associated with more active participation. The level of support for forest conservation was also positively related to households' leadership in village institutions and higher levels of well-being, particularly subjective well-being, land tenure, and material wealth. These social-demographic factors are important considerations when designing and implementing community-based forest management, which strives for fair and just decision-making processes along with forest conservation. The findings highlight how existing socioeconomic contexts factor into local institutions, and that accounting for these in program design and implementation may help address existing social inequalities that influence achieving joint social and ecological objectives
KELT-8b: A highly inflated transiting hot Jupiter and a new technique for extracting high-precision radial velocities from noisy spectra
We announce the discovery of a highly inflated transiting hot Jupiter
discovered by the KELT-North survey. A global analysis including constraints
from isochrones indicates that the V = 10.8 host star (HD 343246) is a mildly
evolved, G dwarf with K, , , an inferred mass
M, and radius
R. The planetary companion has mass , radius
, surface gravity , and density
g cm. The planet is on a roughly
circular orbit with semimajor axis AU and
eccentricity . The best-fit linear ephemeris is
BJD and
days. This planet is one of the most inflated of all known transiting
exoplanets, making it one of the few members of a class of extremely low
density, highly-irradiated gas giants. The low stellar and large
implied radius are supported by stellar density constraints from follow-up
light curves, plus an evolutionary and space motion analysis. We also develop a
new technique to extract high precision radial velocities from noisy spectra
that reduces the observing time needed to confirm transiting planet candidates.
This planet boasts deep transits of a bright star, a large inferred atmospheric
scale height, and a high equilibrium temperature of
K, assuming zero albedo and perfect heat redistribution, making it one of the
best targets for future atmospheric characterization studies.Comment: Submitted to ApJ, feedback is welcom
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Heterogeneous impacts of community forestry on forest conservation and poverty alleviation: evidence from Indonesia
1. Community forestry is a participatory approach aiming to achieve sustainable forest management while also reducing poverty among rural communities. Yet, evidence of the impacts of community forestry programmes on both forest conservation and poverty alleviation is scarce, and there is limited understanding of impacts across different social and biophysical contexts.
2. We applied a matching method to assess the extent to which deforestation has decreased and village wellâbeing has improved as a result of Indonesia's community forestry scheme, Hutan Desa (Village Forest). We assessed five dimensions of wellâbeing: basic (living conditions), physical (access to health and education), financial (income support), social (security and equity) and environmental (natural hazard prevention).
3. We found that Hutan Desa was associated with reduced deforestation and poverty. âWinâwinâ outcomes were found in 51% of cases, comprising (a) positive outcomes for both forests and poverty, (b) a positive outcome for one aspect and a negligible outcome for the other, or (c) a positive outcome for poverty in areas where natural forest had already been lacking prior to Hutan Desa tenure. Benefits to forests and people systematically differed depending on landâuse zones, reflecting subtle interactions between anthropogenic pressures and community livelihood characteristics.
4. In Watershed Protection Zones, which are dominated by subsistenceâbased forest livelihoods, community forestry provided mild conservation benefits, but resulted in the greatest improvements in wellâbeing through improved land tenure. In Limited Production Zones, community forestry provided modest benefits for both conservation and wellâbeing because restrictions on timber harvest due to Hutan Desa designation reduced the financial wellâbeing of logging communities. The greatest conservation benefits were experienced in Permanent or Convertible Production Zones, but wellâbeing improvements were minimal. Here, living conditions and environmental wellâbeing were reduced due to pressure to intensify agricultural production under increased land scarcity in these predominantly cash cropâoriented communities.
5. Our results highlight the spatial and contextual variation in impacts of community forestry policies on poverty alleviation and forest conservation outcomes. Crucially, our study provides vital objective information for future policy development in Indonesia and other tropical countries implementing community forestry schemes
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Toward improved impact evaluation of community forest management in Indonesia
Many tropical countries continue to devolve forest management to forestâdwelling communities. The assumption is that local knowledge of forests and community engagement in forest management will attain multiple social and environmental coâbenefits, such as poverty alleviation and reduced deforestation and fires. Evidence for this, however, is scant, commonly hampered by data availability and a lack of technical capacity for implementing statistically robust impact evaluations. Based on a practiceâbased review of policy implementation, impact evaluation of case studies and examples of counterfactual analyses from Indonesia, we demonstrate that it is increasingly feasible to determine the conditions under which community forest management will most likely achieve its social and environmental objectives. Adapting community forest management implementation based on feedback from accurate impact evaluation could lead to positive outcomes for people and environment in Indonesia, and across the tropical realm
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