Marine protected areas: a tool for integrated coastal management in Belize

Management of the Belize Barrier Reef was originally envisioned through the creation of marine protected areas. However, the influence of land-based activities was not accounted for in Marine Protected Area (MPA) programs. Therefore focus was shifted to an integrated approach via Integrated Coastal Management (ICM). The Belize ICM process has evolved into a system of coordination through the fostering of multi-sectoral linkages for integrated management of coastal resources. Marine protected areas were included in the ICM program as tools for achieving biodiversity protection and management of sensitive habitats. The ICM process has resulted in greater coordination and consultation in decision making for coastal resource issues, the MPA program however has not evolved with the trend of greater community involvement in MPA management. The greatest challenges to MPA and ICM programs in the next 10 years are: improved linkages between the two, fostering of community participation in management, broadening of the scope of ICM to watersheds and ocean governance, and sustainable financing for both programs.     

Dilation and Spalling in Axially Compressed Beams Subjected to Bending

Laboratory testing of rectangular beams using a synthetic rock was used to investigate the onset of dilation and spalling. The beams are axially compressed and subjected to 4-point bending to provide non-uniform compressive stresses. The maximum tangential stress occurs at the top of the beam and rapidly decreases with distance from the top of the beam. This stress distribution was used to simulate the maximum tangential stress distribution found around circular excavations. The results showed using this beam test configuration that the onset of dilation based on beam displacement and visually observed spalling began at approximately the same stress level. Discrete element numerical analyses (particle flow code) were used to evaluate the stress path at various locations in the beams. The analyses revealed that spalling and dilation in the beams occurred well below the peak strength failure envelope determined from conventional laboratory tests. The findings suggest that the onset of dilation in laboratory tests appears to be a good indicator for assessing the stress magnitudes required to initiate spalling.     

Development and application of a novel miniature in situ microprofiler (NAFRI BelpI)

We have developed a novel miniature in situ microprofiler (NAFRI BelpI) for coastal and deep-sea studies. The BelpI can carry up to three oxygen microsensors, and it allows for simultaneous replicate measurements in a relatively small area. All functions can be controlled and programmed via a small magnetic bar and three reed switches; this feature facilitates the initial setup both onboard and underwater. The large LCD window shows basic information such as the movement intervals of the linear stage, number of replicate measurements, waiting time between measurements, and the pA from the microsensors. From high-resolution vertical profiles of oxygen in coastal sediment measured using the microsensors, the diffusivity boundary layer thicknesses was determined to be in the range 0.30–0.35 mm. In addition, the time-series measurement of oxygen profiles in permeable sandy sediment showed advective transport of oxygen into pore water by tidal agitation. Two examples of in situ measurement using a BelpI suggest that it can be widely applied to the study of the sediment-water interface.     

Dynamic analysis of ground with rigorous use of strain dependency and its application to seismic microzonation of alluvial plane

Seismic microzonation is one of the most important measures to mitigate earthquake hazards in urban areas. Because the ground motion varies significantly with the subsurface geology, it is needed for microzonation to account as much as possible for the local soil conditions. Noteworthy is that nonlinear deformation properties of soil play essential roles in amplification of strong ground motion. It is desired furthermore to focus on the expected damage extent in addition to the calculated maximum acceleration and/or velocity. The present study first developed a computer code for one-dimensional response analysis of ground that reasonably takes into account nonlinear dynamic soil properties. Second, correlations between the calculated ground motion and damage extent were obtained by examining seismic damages during the past earthquakes. By combining these two issues, seismic microzonation was carried out, and detailed damage distribution was assessed. The product of this study covers not only the damage caused by ground shaking but also liquefaction problem and lifeline damage.     

Volatilization of sodium from silicate melt spheres and its application to the formation of chondrules

The rates of volatilization of Na from liquid spheres of chondrule compositions have been determined as functions of time, temperature, partial pressure of oxygen, and sizes of the spheres. The Na₂O content in the sphere is uniform in each run. but it decreases with time of the run, indicating that the rate of diffusion of Na in the liquid is greater than that of volatilization, and that the latter is the rate-controlling process. The rate of sodium volatilization becomes greater with increasing temperature and with decreasing P_O2 and size of the spheres. The relation of the Na₂O content in the liquid sphere with time and its size indicate that the amount of Na₂O volatilized from the liquid spheres within unit time is proportional to the surface area of the spheres and the concentration of Na₂O in the liquid. From these relations, the rate of volatilization of sodium can be obtained at constant temperature and P_o2. The rate of volatilization of sodium satisfies the Arrhenius relation within the temperature range from about 1450–1600 C at 10^?9,2 atm p_O2; the activation energy for the sodium volatilization is approximately 100 kcal-mole^?1. The rate is also approximately proportional to within the range of p_O2 from 10^?10.2 to 10^?5.0 atm at about 1500° C. Based on the present results and the Na₂O contents in chondrules. it is suggested that they experienced an instant heating with maximum temperature of 1400–2200° C followed by an immediate cooling.     

On the relationship of cosmic ray intensity with solar,interplanetary, and geophysical parameters

The flux rate of cosmic rays incident on the Earth’s upper atmosphere is modulated by the solar wind and the Earth’s magnetic field. The amount of solar wind is not constant due to changes in solar activity in each solar cycle, and hence the level of cosmic ray modulation varies with solar activity. In this context, we have investigated the variability and the relationship of cosmic ray intensity with solar, interplanetary, and geophysical parameters from January 1982 through December 2008. Simultaneous observations have been made to quantify the exact relationship between the cosmic ray intensity and those parameters during the solar maxima and minima, respectively. It is found that the stronger the interplanetary magnetic field, solar wind plasma velocity, and solar wind plasma temperature, the weaker the cosmic ray intensity. Hence, the lowest cosmic ray intensity has good correlations with simultaneous solar parameters, while the highest cosmic ray intensity does not. Our results show that higher solar activity is responsible for a higher geomagnetic effect and vice versa.     

Dinoflagellate Cysts in Coastal Sediments as Indicators of Eutrophication: A Case of Gwangyang Bay,South Sea of Korea

Diatom densities in the surface water and dinoflagellate cysts in bottom sediments of Gwangyang Bay were studied to determine changes in the phytoplankton community structure in response to anthropogenic eutrophication and to assess the use of dinoflagellate cysts as indicators of coastal eutrophication. Our results show that, in nutrient-enriched environments, diatoms are particularly benefited from the nutrients supplied and, as a consequence, heterotrophic dinoflagellates that feed on the diatoms can be more abundant than autotrophic dinoflagellates. In short-core sediment records, a marked shift in autotrophic–heterotrophic dinoflagellate cyst compositions occurred at a depth of approximately 9–10 cm corresponding to the timing of the 1970s industrialization around Gwangyang Bay. This tentatively indicates that diatom and dinoflagellate communities here have undergone a considerable change mainly due to increased nutrient loadings from both domestic sewage effluent and industrial pollution. Our study suggests a possible potential use of dinoflagellate cysts in providing retrospective information on the long-term effects of coastal eutrophication.     

Temperature of Solar Prominences Obtained with the Fast Imaging Solar Spectrograph on the 1.6 m New Solar Telescope at the Big Bear Solar Observatory

We observed solar prominences with the Fast Imaging Solar Spectrograph (FISS) at the Big Bear Solar Observatory on 30 June 2010 and 15 August 2011. To determine the temperature of the prominence material, we applied a nonlinear least-squares fitting of the radiative transfer model. From the Doppler broadening of the Hα and Ca ii lines, we determined the temperature and nonthermal velocity separately. The ranges of temperature and nonthermal velocity were 4000?–?20?000 K and 4?–?11 km?s^?1. We also found that the temperature varied much from point to point within one prominence.     

Fast Imaging Solar Spectrograph of the 1.6 Meter New Solar Telescope at Big Bear Solar Observatory

For high resolution spectral observations of the Sun – particularly its chromosphere, we have developed a dual-band echelle spectrograph named Fast Imaging Solar Spectrograph (FISS), and installed it in a vertical optical table in the Coudé Lab of the 1.6 meter New Solar Telescope at Big Bear Solar Observatory. This instrument can cover any part of the visible and near-infrared spectrum, but it usually records the Hα band and the Ca ii 8542 Å band simultaneously using two CCD cameras, producing data well suited for the study of the structure and dynamics of the chromosphere and filaments/prominences. The instrument does imaging of high quality using a fast scan of the slit across the field of view with the aid of adaptive optics. We describe its design, specifics, and performance as well as data processing     

An integrated Bayesian approach to the probabilistic tsunami risk model for the location and magnitude of earthquakes: application to the eastern coast of the Korean Peninsula

We explored the distributional changes in tsunami height along the eastern coast of the Korean Peninsula resulting from virtual and historical tsunami earthquakes. The results confirm significant distributional changes in tsunami height depending on the location and magnitude of earthquakes. We further developed a statistical model to jointly analyse tsunami heights from multiple events, considering the functional relationships; we estimated parameters conveying earthquake characteristics in a Weibull distribution, all within a Bayesian regression framework. We found the proposed model effective and informative for the estimation of tsunami hazard analysis from an earthquake of a given magnitude at a particular location. Specifically, several applications presented in this study showed that the proposed Bayesian approach has the advantage of conveying the uncertainty of the parameter estimates and its substantial effect on estimating tsunami risk.