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1.
Conserv Biol ; 35(4): 1174-1185, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33319392

RESUMO

Private lands provide key habitat for imperiled species and are core components of function protectected area networks; yet, their incorporation into national and regional conservation planning has been challenging. Identifying locations where private landowners are likely to participate in conservation initiatives can help avoid conflict and clarify trade-offs between ecological benefits and sociopolitical costs. Empirical, spatially explicit assessment of the factors associated with conservation on private land is an emerging tool for identifying future conservation opportunities. However, most data on private land conservation are voluntarily reported and incomplete, which complicates these assessments. We used a novel application of occupancy models to analyze the occurrence of conservation easements on private land. We compared multiple formulations of occupancy models with a logistic regression model to predict the locations of conservation easements based on a spatially explicit social-ecological systems framework. We combined a simulation experiment with a case study of easement data in Idaho and Montana (United States) to illustrate the utility of the occupancy framework for modeling conservation on private land. Occupancy models that explicitly accounted for variation in reporting produced estimates of predictors that were substantially less biased than estimates produced by logistic regression under all simulated conditions. Occupancy models produced estimates for the 6 predictors we evaluated in our case study that were larger in magnitude, but less certain than those produced by logistic regression. These results suggest that occupancy models result in qualitatively different inferences regarding the effects of predictors on conservation easement occurrence than logistic regression and highlight the importance of integrating variable and incomplete reporting of participation in empirical analysis of conservation initiatives. Failure to do so can lead to emphasizing the wrong social, institutional, and environmental factors that enable conservation and underestimating conservation opportunities in landscapes where social norms or institutional constraints inhibit reporting.


La incorporación de las tierras privadas a la planeación de la conservación regional y nacional ha sido un reto a pesar de su importancia como hábitat para especies en peligro y como componentes nucleares de las redes funcionales de áreas protegidas. La identificación de las localidades en donde sea probable que los propietarios privados participen en las iniciativas de conservación puede ayudar a evitar conflictos costosos y a aclarar las compensaciones entre los beneficios ecológicos y los costos sociopolíticos. La evaluación empírica y espacialmente explícita de los factores asociados con la conservación en tierras privadas es una herramienta emergente usada para la identificación de oportunidades de conservación en el futuro. Sin embargo, la mayoría de los datos sobre la conservación en tierras privadas es reportada voluntariamente y está incompleta, lo cual complica realizar estas evaluaciones. Usamos una aplicación novedosa de los modelos de ocupación para analizar la presencia de la mitigación por conservación en tierras privadas. Comparamos diferentes formulaciones de los modelos de ocupación con un modelo de regresión logística para predecir las localidades de la mitigación por conservación con base en un marco de trabajo de un sistema socioecológico espacialmente explícito. Combinamos un experimento de simulación con un estudio de caso sobre datos de mitigación en Idaho y Montana (Estados Unidos) para ilustrar la utilidad del marco de trabajo de ocupación para el modelado de la conservación en tierras privadas. Los modelos de ocupación que consideraron explícitamente la variación en los reportes produjeron estimados de los predictores que estuvieron sustancialmente menos sesgados que los estimados producidos por la regresión logística bajo todas las condiciones simuladas. Los modelos de ocupación produjeron estimaciones para seis predictores que evaluamos en nuestro estudio de caso, los cuales fueron mayores en magnitud pero menos certeros que aquellos producidos por la regresión logística. Estos resultados sugieren que los modelos de ocupación tienen como resultado inferencias cualitativamente diferentes a la regresión logística con respecto a los efectos de los predictores sobre la presencia de mitigación por conservación y resaltan la importancia de la integración de los reportes variables e incompletos sobre la participación dentro del análisis empírico de las iniciativas de conservación. Si se falla en lo anterior se puede terminar enfatizando el factor social, institucional y ambiental equivocado que permite la conservación, además de subestimar las oportunidades de conservación en paisajes en donde las normas sociales o las restricciones institucionales inhiben el reporte de datos.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Simulação por Computador , Custos e Análise de Custo , Montana , Estados Unidos
2.
Ecol Appl ; 29(4): e01888, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30916821

RESUMO

Protected areas are one of the most effective means by which biodiversity is conserved, but are often criticized for either neglecting the importance of local communities or sacrificing conservation objectives for political expedience. In the United States, federal protected areas can be designated via a democratic legislation process or via executive action, which allows for comparison of the ecological and sociopolitical context of these top-down and bottom-up processes. We compared protected areas resulting from congressional designation vs. presidential designation with respect to their ecological context (using measures of biodiversity and climate refugial potential) and sociopolitical context (using measures of local support for conservation and reliance on natural resource-based industries). We found minimal differences between these designation modes for both ecological and sociopolitical variables. These results suggest that presidentially designated protected areas tend to be no more burdensome to local communities and no less valuable for ecological conservation than more widely accepted federal protected areas such as national parks, and they provide new evidence to inform the current debate over national monuments.


Assuntos
Conservação dos Recursos Naturais , Ecologia , Biodiversidade , Recursos Naturais , Parques Recreativos , Estados Unidos
3.
Conserv Biol ; 32(4): 926-937, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29297934

RESUMO

Conservation practice has demonstrated an increasing desire for accountability of actions, particularly with respect to effectiveness, efficiency, and impact to clearly identified objectives. This has been accompanied by increased attention to achieving adaptive management. In 2002, practitioners representing several prominent conservation nongovernmental organizations (NGOs) launched a community of practice called the Conservation Measures Partnership (CMP). The partnership CMP has worked to establish standards of conservation practice to improve accountability of conservation actions through adaptive management. The focal organizing framework for CMP has been the Open Standards for the Practice of Conservation (OS). We evaluated, through an online survey and personal interviews, the first decade of CMP and the OS. The CMP has garnered a positive reputation among agencies, NGOs, and funders and has succeeded in developing a large user base of the OS. However, CMP has not fully achieved its goal of making the OS standard operating procedure for the largest NGOs (e.g., The Nature Conservancy, World Wildlife Fund), despite it being widely used within these organizations. This lack of institutionalization is attributable to multiple causes, including an increase in the number of partially overlapping decision-support frameworks and challenges achieving full-cycle adaptive management. Users strongly believed the OS fosters better conservation practice and highly valued the OS for improving their practice. A primary objective of the OS is to assist practitioners to achieve full-cycle adaptive management to better integrate learning into improving the effectiveness and efficiency of actions. However, most practitioners had not yet achieved cycle completion for their projects. To improve the effectiveness of CMP, OS, and conservation practice in general, we recommend collaborative efforts among the proponents of multiple decision-support frameworks to foster strong institutional adoption of a common set of adaptive-management standards for conservation accountability.


Assuntos
Conservação dos Recursos Naturais , Organizações , Aprendizagem
4.
Int J Radiat Oncol Biol Phys ; 88(3): 746-52, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24411623

RESUMO

PURPOSE: A novel (32)P brachytherapy source has been in use at our institution intraoperatively for temporary radiation therapy of the spinal dura and other localized tumors. We describe the dosimetry and clinical implementation of the source. METHODS AND MATERIALS: Dosimetric evaluation for the source was done with a complete set of MCNP5 Monte Carlo calculations preceding clinical implementation. In addition, the depth dose curve and dose rate were measured by use of an electron field diode to verify the Monte Carlo calculations. Calibration procedures using the diode in a custom-designed phantom to provide an absolute dose calibration and to check dose uniformity across the source area for each source before treatment were established. RESULTS: Good agreement was established between the Monte Carlo calculations and diode measurements. Quality assurance measurements results are provided for about 100 sources used to date. Clinical source calibrations were usually within 10% of manufacturer specifications. Procedures for safe handling of the source are described. DISCUSSION: Clinical considerations for using the source are discussed.


Assuntos
Braquiterapia/métodos , Dura-Máter , Neoplasias Meníngeas/radioterapia , Método de Monte Carlo , Radioisótopos de Fósforo/uso terapêutico , Braquiterapia/instrumentação , Calibragem , Física Médica/métodos , Humanos , Neoplasias Meníngeas/patologia , Imagens de Fantasmas , Controle de Qualidade , Proteção Radiológica/instrumentação , Dosagem Radioterapêutica
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