Climate change reporting for rural broadcasters Engaging rural media for community mobilization on climate-smart agriculture in the Philippines

To kick off a pilot rural radio campaign on climate-smart agriculture (CSA), three seminar workshops titled “Climate Change: iBroadkas Mo!”, for rural broadcasters in the Philippines were organized by the Philippine Federation of Rural Broadcasters (PFRB), with the support of the CGIAR Research Program on Climate Change, Agriculture and Food Security in Southeast Asia (CCAFS-SEA). Participants for these seminar workshops were member broadcasters of the PFRB in strategic regions of the Philippines. Moreover, it was also attended by other media practitioners and government information officers from around the area. Participants to the workshops were familiarized with climate change concepts to improve their capacities in broadcasting climate-related issues and concepts to their audiences. The total number of participants for the whole series was 180 which included 147 practicing broadcasters, 19 government information officers and five staff members from the PFRB. Presentations and discussions during the workshops focused on CSA and techniques and practices for broadcasting climate-related issues effectively. Participants were asked to produce prototype scripts and radio programs, which may include two radio spots, a short interview or voice clips of experts, on CSA as their output for the workshops. The PFRB campaign on climate change, which was launched during the workshops, will engage the services and programs of 150 rural broadcasters in the Philippines in mobilizing the rural sector (particularly farmers, fisherfolk and rural women) and advocating the practice of climate smart agriculture. Members of the PFRB and their network of community radio practitioners will be provided with ready-to-be-aired interviews and scripts on climate-smart agriculture. The broadcast materials will be produced in the languages of selected pilot regions. To motivate broadcasters, a reward and incentive system based on listenership and impact shall be put in place

Eighty years of food-web response to interannual variation in discharge recorded in river diatom frustules from an ocean sediment core.

Little is known about the importance of food-web processes as controls of river primary production due to the paucity of both long-term studies and of depositional environments which would allow retrospective fossil analysis. To investigate how freshwater algal production in the Eel River, northern California, varied over eight decades, we quantified siliceous shells (frustules) of freshwater diatoms from a well-dated undisturbed sediment core in a nearshore marine environment. Abundances of freshwater diatom frustules exported to Eel Canyon sediment from 1988 to 2001 were positively correlated with annual biomass of Cladophora surveyed over these years in upper portions of the Eel basin. Over 28 years of contemporary field research, peak algal biomass was generally higher in summers following bankfull, bed-scouring winter floods. Field surveys and experiments suggested that bed-mobilizing floods scour away overwintering grazers, releasing algae from spring and early summer grazing. During wet years, growth conditions for algae could also be enhanced by increased nutrient loading from the watershed, or by sustained summer base flows. Total annual rainfall and frustule densities in laminae over a longer 83-year record were weakly and negatively correlated, however, suggesting that positive effects of floods on annual algal production were primarily mediated by "top-down" (consumer release) rather than "bottom-up" (growth promoting) controls

THE ROLE OF PREDATORS IN THE ECOLOGY, EPIDEMIOLOGY, AND SURVEILLANCE OF PLAGUE IN THE UNITED STATES

Predators play important roles in the ecology, epidemiology, and surveillance of plague in the United States. Most predators are accidental hosts of plague and, with the possible exception of grasshopper mice (Onychomys spp.), are not important sources of infection for feeding fleas. However, predators undoubtedly do play an important role in the natural cycle of plague by transporting infected fleas between different populations of plague-susceptible rodents. Predators are known to be at least accidental hosts for 40 of the 50 flea species that have been found to be naturally infected with plague in the U.S. Carnivores, including domestic cats, also play an important epidemiological role and have been sources of infection for 24 human plague cases since 1970. Serosurveillance of rodent-consuming carnivores is currently the most cost-effective method of monitoring plague in the western U.S. During the 1990s, these surveys have allowed CDC and other public health agencies to both identify plague risks for humans living in endemic regions and document the spread of plague into areas where it had not been identified previously

Revisiting Hafemeister’s ‘Science and Society’ Tests

We revisit a series of papers on science and society issues by David Hafemeister in the 1970s and 1980s. The emphasis in the present work is on world oil production limits and some consequences of various possible scenarios for the near future. Some of the data and scenarios used by Hafemeister are updated for U.S. oil production in the past two decades and extended to an analysis of a peak in world oil production in the future. We discuss some simple scenarios for future energy use patterns and look at the consequence of these scenarios as world oil production begins to decline. We also provide a list of resources for critical investigations of natural resource extraction and depletion patterns

Dramatic Shape Sensitivity of Directional Emission Patterns from Similarly Deformed Cylindrical Polymer Lasers

Recent experiments on similarly shaped polymer micro-cavity lasers show a dramatic difference in the far-field emission patterns. We show for different deformations of the ellipse, quadrupole and hexadecapole that the large differences in the far-field emission patterns is explained by the differing ray dynamics corresponding to each shape. Analyzing the differences in the appropriate phase space for ray motion, it is shown that the differing geometries of the unstable manifolds of periodic orbits are the decisive factors in determining the far-field pattern. Surprisingly, we find that strongly chaotic ray dynamics is compatible with highly directional emission in the far-field.Comment: 14 pages, 16 figures (eps), RevTeX 4, submitted to JOSA

Fire in Southern Appalachians: Fuels, Stand Structure and Oaks

Managers responsible for maintaining the diversity and productivity of Southern Appalachian forests are increasingly turning to prescribed fire as an important management tool in oak dominated forests. The decision to use fire with increasing frequency and spatial extent is based, in part, on an emerging sense of the prehistoric significance of fire in this landscape and its potential to control the proliferation of fire-sensitive competitors in contemporary forests. While it is well documented that fire has been an important ecological force in Southern Appalachian forests for a very long time, there has been little research to demonstrate that prescribed fire effectively controls fire-sensitive competitors, promotes regeneration of desirable species, or maintains and promotes healthy forest stands. In the face of increased management burning there is a need to address these questions, and to quantify the role of existing and residual fuels in fire management following repeated fire of differing intervals. Two studies were initiated in 1995 and 2002 in upland forests on the Cumberland Plateau of Kentucky to examine the effectiveness of prescribed fire to maintain oak dominance by altering stand structure and enhancing oak seedling establishment and development. We hypothesized that fire would: (1) reduce midstory stem density, and that these changes to stand structure and light availability would lead to improved performance of oak seedlings; and (2) control oak competitors. On ridgetop sites on the escarpment of the Cumberland Plateau, we measured stand structure and tree regeneration on 48 plots in 6 treatment areas over an 11-year period. Four units were burned 3-4 times and two units serve as fire-excluded references. On the topographically-dissected landscape of the Cumberland Plateau we recorded stand structure and multiple aspects of the tree regeneration process on 9 study sites (93 plots), with three sites burned four times, three sites burned twice, and three fire-excluded sites. Prescribed fire reduced midstory stem density and basal area, and increased light availability which was transitory due to understory sprouting. Seedling population studies revealed that oaks and maple seedlings responded to stem kill by re-sprouting, with increased height and diameter. However, red maple seedlings grew more than oaks after burning. Burning reduced seedling density of potential competitor species, yet high fecundity of some species (e.g., red maple) and strong sprouting response of others (e.g., sassafras), suggests that multiple fires have provided neither the stand structural changes nor competition control that would lead to the development of more competitive oak advance reproduction. An oak mast event revealed a potentially positive role for fire in reducing the depth of the litter layer and enhancing oak seedling establishment and growth. Overall, our results suggest a modest role for prescribed fire in enhancing the establishment, growth and persistence of oak advance regeneration

Polarization properties and dispersion relations for spiral resonances of a dielectric rod

Dielectric microcavities based on cylindrical and deformed cylindrical shapes have been employed as resonators for microlasers. Such systems support spiral resonances with finite momentum along the cylinder axis. For such modes the boundary conditions do not separate and simple TM and TE polarization states do not exist. We formulate a theory for the dispersion relations and polarization properties of such resonances for an infinite dielectric rod of arbitrary cross-section and then solve for these quantities for the case of a circular cross-section (cylinder). Useful analytic formulas are obtained using the eikonal (Einstein-Brillouin-Keller) method which are shown to be excellent approximations to the exact results from the wave equation. The major finding is that the polarization of the radiation emitted into the far-field is linear up to a polarization critical angle (PCA) at which it changes to elliptical. The PCA always lies between the Brewster and total-internal-reflection angles for the dielectric, as is shown by an analysis based on the Jones matrices of the spiraling rays.Comment: submitted to JOSA

Fresnel filtering in lasing emission from scarred modes of wave-chaotic optical resonators

We study lasing emission from asymmetric resonant cavity (ARC) GaN micro-lasers. By comparing far-field intensity patterns with images of the micro-laser we find that the lasing modes are concentrated on three-bounce unstable periodic ray orbits, i.e. the modes are scarred. The high-intensity emission directions of these scarred modes are completely different from those predicted by applying Snell's law to the ray orbit. This effect is due to the process of ``Fresnel filtering'' which occurs when a beam of finite angular spread is incident at the critical angle for total internal reflection.Comment: 4 pages, 3 figures (eps), RevTeX 3.1, submitted to Phys. Rev. Lett; corrected a minor (transcription) erro