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1.
J Emerg Manag ; 19(8): 217-234, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36239510

RESUMO

Puerto Rico experienced the most prolonged power outage in US history after two hurricanes hit the Archipelago in September 2017. Hurricane Irma left over one million people without electricity, and Hurricane Maria left Puerto Rico in a total blackout when it hit. The damages to 80 percent of the electrical grid opened the possibility to the Puerto Rico Electric Power Authority to explore options beyond merely reconstructing and keeping the grid centralized. Prior to these events, an active public discussion on how to transform the electrical system had been occurring regarding a new energy policy passed in 2014 that created Puerto Rico's first Energy Commission and concerning the first Integrated Resource Plan approved in 2016. OBJECTIVE: This study aimed to examine stakeholders' visions, values, perceived barriers, and opportunities for a sustainable energy transition before the 2017 Atlantic Hurricane Season and how the stakeholders' perspectives have been manifesting during post-disaster efforts. DESIGN: This study examined working documents generated by an Energy Stakeholders Forum (ESF) and semistructured interviews with key stakeholders in the energy decision-making arena. SETTING: The data analyzed in this study were collected for 2 years (2015-2016) before Hurricanes Irma and Maria hit Puerto Rico. The ESF had a series of meetings to generate multisectoral dialog and pursue more public participation in energy policy and planning processes. The semistructured interviews were conducted as part of an NSF-Critical Resilient Infrastructure Systems and Processes project investigating stakeholders' perspectives on the electrical system. PARTICIPANTS: Thirty-one stakeholders participated in face-to-face semistructured interviews using purposive and snowball sampling. The ESF's meetings not only gathered up to 60 key stakeholders but also were open to the public. RESULTS: This study suggests that stakeholders' perspectives were consistent with the prerequisites for a transition to renewable energy before the 2017 Atlantic Hurricane Season. However, even though the conditions of vision and values were present, there was also predisaster inertia from nontechnical barriers preventing the sustainable transition that still prevails in post-disaster Puerto Rico. CONCLUSION: This paper provides an empirical reflection that ponders Puerto Rico's post-disaster scenario through predisaster stakeholders' perspectives. Emergency management professionals should reflect on why understanding predisaster conditions is critical in order to promote recovery efforts that meet the long-term needs of society and support sustainable development for future generations. The analysis may also reinforce planning for disaster recovery via governance approaches that consider stakeholders' perspectives before disasters strike.


Assuntos
Tempestades Ciclônicas , Desastres , Humanos , Porto Rico , Energia Renovável , Estações do Ano
2.
Am J Bot ; 106(7): 996-1010, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31281957

RESUMO

PREMISE: Gesneria pauciflora is a rare, threatened plant in riparian forests. Periodic disturbances, expected in this habitat, could influence demographic dynamics on plant populations, yet their impact may not be the same across the watershed. We hypothesized that differences in disturbances between the main channel and tributaries may lead to spatial dissimilarities in population growth rate (λ), structure, and fecundity. METHODS: In the Maricao River Watershed in Puerto Rico, 1277 plants were tagged and monitored for 1.5 years. Every 6 months, we measured plant size and recorded survival, fecundity, and appearance of seedlings. These variables were used in integral projection models to assess the population status of G. pauciflora. RESULTS: Plants in the main channel were smaller but more likely to flower and fruit than those in the tributaries. Overall mortality was greater in the main channel and greater during the rainy season. At both sites, λ ranged from 0.9114 to 0.9865, and survival/growth of larger plants had a greater effect on λ (>0.90) regardless of site. CONCLUSIONS: Values for population growth rates suggest that G. pauciflora is declining across the watershed. Higher mortality rates in the main channel (more-perturbed sites) might drive G. pauciflora to reproduce at smaller sizes, while tributaries (less-perturbed sites) might be better for growth and lead to larger plant sizes. Extreme climatic events are expected to increase in the Caribbean and might decrease the population if the population is left unmanaged. Management strategies that reduce the time plants require to reach larger sizes might be necessary to increase λ, and reintroduction using cuttings might be a possible solution.


Assuntos
Lamiales , Rios , Ecossistema , Modelos Estatísticos , Dinâmica Populacional , Porto Rico
3.
Oecologia ; 179(2): 415-24, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26054613

RESUMO

Movement has broad implications for many areas of biology, including evolution, community and population ecology. Movement is crucial in metapopulation ecology because it facilitates colonization and reduces the likelihood of local extinction via rescue effects. Most metapopulation modeling approaches describe connectivity using pair-wise Euclidean distances resulting in the simplifying assumption of a symmetric connectivity pattern. Yet, assuming symmetric connectivity when populations show net asymmetric movement patterns may result in biased estimates of colonization and extinction, and may alter interpretations of the dynamics and conclusions regarding the viability of metapopulations. Here, we use a 10-year time series on a wind-dispersed orchid Lepanthes rupestris that anchors its roots in patches of moss growing on trees or boulders along streams, to test for the role of connectivity asymmetries in explaining the colonization-extinction dynamics of this orchid in a network of 975 patches. We expected that wind direction could highly alter dispersal direction in this orchid. To account for this potential asymmetry, we modified the connectivity measure traditionally used in metapopulation models to allow for asymmetric effective distances between patches and subsequently estimated colonization and extinction probabilities using a dynamic occupancy modeling approach. Asymmetric movement was prevalent in the L. rupestris metapopulation and incorporating potential dispersal asymmetries resulted in higher colonization estimates in larger patches and more accurate models. Accounting for dispersal asymmetries may reveal connectivity effects where they were previously assumed to be negligible and may provide more reliable conclusions regarding the role of connectivity in patch dynamics.


Assuntos
Extinção Biológica , Modelos Biológicos , Orchidaceae/fisiologia , Ecologia , Ecossistema , Dinâmica Populacional , Dispersão de Sementes , Vento
4.
Rev. bras. entomol ; 56(1): 119-121, jan.-mar. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-624638

RESUMO

New distribution record of Cybocephalus Kathrynae (Coleoptera, Cybocephalidae) on Mona Island, Puerto Rico. A new record of Cybocephalus kathrynae T.R. Smith (Cybocephalidae) is reported for Puerto Rico. Adults were collected from the flowers of Mammillaria nivosa (Cactaceae) on Mona Island Reserve. Prior to this study, this beetle species was only reported for Monroe and Miami-Dade Counties, Florida, USA.


Novo registro de distribuição de Cybocephalus Kathrynae (Coleoptera, Cybocephalidae) na Ilha de Mona, Puerto Rico. Um novo registro de Cybocephalus kathrynae T. R. Smith (Cybocephalidae) é reportado para Puerto Rico. Os adultos foram coletados em flores de Mammillaria nivosa (Cactaceae) na Reserva da Ilha de Mona. Antes da realização deste estudo, esta espécie apenas havia sido registrada nos condados de Monroe e Miami-Dade na Florida, EUA.

5.
Am J Bot ; 98(12): 2040-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22106437

RESUMO

PREMISE OF THE STUDY: Biotic changes are an inevitable consequence of climate change. Epiphytes may be more susceptible to changes in climate variation, but data regarding responses to climate variability under field conditions are limited. We evaluated whether the abundance of demographic stages in the epiphytic orchid Lepanthes rupestris at the Luquillo Experimental Forest in Puerto Rico was associated with short-term changes in climate variation over an 8-yr period. METHODS: We used cross-correlation analyses to evaluate associations between the abundance of seedlings, juveniles, adults, and fruits per subpopulation, population growth, colonization and extinction rates in L. rupestris with variables related to precipitation and temperature, with and without lag- responses. KEY RESULTS: We detected significant negative correlations between the average number of seedlings and the number of dry days, between the average number of fruits and minimum average temperature with a 6-mo response lag, and between the average number of adults and the maximum temperature with a 1-yr response lag. Neither population growth rate nor probability of colonization and extinction were directly related to climatic variation between 2000 and 2007. CONCLUSIONS: Associations between climatic variables and demographic stages could have negative implications for this orchid within the context of expected drying trends in the Caribbean. Results argue for the establishment of long-term monitoring studies of orchid populations, because only long-term studies would provide the appropriate temporal scale to detect and predict climate change effects and adaptive management of orchid populations.


Assuntos
Orchidaceae/crescimento & desenvolvimento , Simbiose , Clima , Densidade Demográfica , Dinâmica Populacional , Porto Rico
6.
Am J Bot ; 94(3): 419-24, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21636411

RESUMO

The effectiveness of flower visitors as pollinators will determine their potential role as selective agents on flower traits. Pitcairnia angustifolia has floral characters that would fit pollination by long-billed hummingbirds, and they should be the most effective pollinators for this plant. To test this prediction, we characterized the behavior of visitors toward flowers and their pollination effectiveness. Coereba flaveola (bananaquits) was the most frequent flower visitor and acted as a primary nectar robber; however, they pollinated incidentally and deposited pollen on stigmas. The endemic short-billed hummingbird Chlorostilbon maugaeus behaved as a secondary robber and did not pollinate flowers. As expected, the long-billed hummingbird, Anthracothorax viridis, was the most efficient visitor in terms of pollen deposition; however, it was the least frequent flower visitor. Introduced Apis mellifera (honeybees) were second in efficiency at depositing pollen and performed one third of the flower visits. Estimates of the expected rate of pollen deposition by each pollinator did not identify a single most effective pollinator. For P. angustifolia at least three flower visitors including an exotic bee and a nectar robber may be equally important to reproductive success. While these results limit our ability to make predictions on the role of hummingbird-pollination on current flower evolution, they do suggest the potential for pollination redundancy among flower visitors for P. angustifolia populations.

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