Differential modulation of eastern oyster (<Emphasis Type="Italic">Crassostrea virginica</Emphasis>) disease parasites by the El-Niño-Southern Oscillation and the North Atlantic Oscillation

The eastern oyster (Crassostrea virginica) is affected by two protozoan parasites, Perkinsus marinus which causes Dermo disease and Haplosporidium nelsoni which causes MSX (Multinucleated Sphere Unknown) disease. Both diseases are largely controlled by water temperature and salinity and thus are potentially sensitive to climate variations resulting from the El Niño-Southern Oscillation (ENSO), which influences climate along the Gulf of Mexico coast, and the North Atlantic Oscillation (NAO), which influences climate along the Atlantic coast of the United States. In this study, a 10-year time series of temperature and salinity and P. marinus infection intensity for a site in Louisiana on the Gulf of Mexico coast and a 52-year time series of air temperature and freshwater inflow and oyster mortality from Delaware Bay on the Atlantic coast of the United States were analyzed to determine patterns in disease and disease-induced mortality in C. virginica populations that resulted from ENSO and NAO climate variations. Wavelet analysis was used to decompose the environmental, disease infection intensity and oyster mortality time series into a time–frequency space to determine the dominant modes of variability and the time variability of the modes. For the Louisiana site, salinity and Dermo disease infection intensity are correlated at a periodicity of 4 years, which corresponds to ENSO. The influence of ENSO on Dermo disease along the Gulf of Mexico is through its effect on salinity, with high salinity, which occurs during the La Niña phase of ENSO at this location, favoring parasite proliferation. For the Delaware Bay site, the primary correlation was between temperature and oyster mortality, with a periodicity of 8 years, which corresponds to the NAO. Warmer temperatures, which occur during the positive phase of the NAO, favor the parasites causing increased oyster mortality. Thus, disease prevalence and intensity in C. virginica populations along the Gulf of Mexico coast is primarily regulated by salinity, whereas temperature regulates the disease process along the United States east coast. These results show that the response of an organism to climate variability in a region is not indicative of the response that will occur over the entire range of a particular species. This has important implications for management of marine resources, especially those that are commercially harvested.     

Mesoscale model simulation of low level equatorial winds over Borneo during the haze episode of September 1997

The large-scale vegetation fires instigated by the local farmers during the dry period of the major El Niño event in 1997 can be considered as one of the worst environmental disasters that have occurred in southeast Asia in recent history. This study investigated the local meteorology characteristics of an equatorial environment within a domain that includes the northwestern part of Borneo from the 17 to 27 September 1997 during the height of the haze episode by utilizing a limited area three-dimensional meteorological and dispersion model, The Air Pollution Model (TAPM).Daily land and sea breeze conditions near the northwestern coast of Borneo in the state of Sarawak, Malaysia were predicted with moderate success by the index of agreement of less than one between the observed and simulated values for wind speed and a slight overprediction of 2.3 of the skill indicator that evaluates the standard deviation to the observed values. The innermost domain of study comprises an area of 24,193 km², from approximately 109°E to 111°E, and from 1°N to 2.3°N, which includes a part of the South China Sea. Tracer analysis of air particles that were sourced in the state of Sarawak on the island of Borneo verified the existence of the landward and shoreward movements of the air during the simulation of the low level wind field. Polluted air particles were transported seawards during night-time, and landwards during daytime, highlighting the recirculation features of aged and newer air particles during the length of eleven days throughout the model simulation. Near calm conditions at low levels were simulated by the trajectory analysis from midnight to mid-day on the 22 of September 1997. Low-level turbulence within the planetary boundary layer in terms of the total kinetic energy was weak, congruent with the weak strength of low level winds that reduced the ability of the air to transport the pollutants.Statistical evaluation showed that parameters such as the systematic RMSE and unsystematic RMSE between the observed and simulated values indicated the modest skill of the model in simulating the low level winds. Otherwise, the equatorial meteorological parameters such as wind speed and temperature were successfully simulated by the model with comparatively high correlation coefficients, lower RMSEs and moderately high indices of agreement with observed values.     

Modeling Bedload Transport of Juvenile Bivalves: Predicted Changes in Distribution and Scale of Postlarval Dispersal

The potential consequences of bedload transport of postlarvae for patterns of distribution of marine invertebrates were explored by developing a bedload transport model for juvenile bivalves in a small estuary in New Jersey, USA. A simple numerical model of tidal current hydrodynamics was developed based on field measurements of shear stresses near the bottom. Burrowing behavior of bivalves was incorporated into the model of bedload transport by using estimates of entrainment rates of Gemma gemma and Mya arenaria in a laboratory flume, and jump lengths of the bivalves were estimated by methods previously developed for noncohesive particles. Based on the flood domination and strong gradient of shear stresses in the Navesink estuary, our model predicted that juvenile bivalves would accumulate in the center of the estuary, traveling up to several kilometers over 30 days. Field distributions of juvenile bivalves were consistent with the model predictions for other species of bivalves but not for G. gemma, for which field distributions of both <500- and >500-μm individuals were concentrated in the eastern end of the estuary. Differences between the bedload model and G. gemma distributions suggest that spatial variation in burrowing behavior or biological interactions are playing an important role in maintaining distribution patterns of this species in spite of high levels of bedload transport. This modeling approach is applicable to other juvenile benthic invertebrates that disperse as bedload and is a useful model against which to compare field observations of rates of transport and patterns of distribution and abundance.     

Sensitivity of MM5 and WRF mesoscale model predictions of surface winds in a typhoon to planetary boundary layer parameterizations

Sea surface winds and coastal winds, which have a significant influence on the ocean environment, are very difficult to predict. Although most planetary boundary layer (PBL) parameterizations have demonstrated the capability to represent many meteorological phenomena, little attention has been paid to the precise prediction of winds at the lowest PBL level. In this study, the ability to simulate sea winds of two widely used mesoscale models, fifth-generation mesoscale model (MM5) and weather research and forecasting model (WRF), were compared. In addition, PBL sensitivity experiments were performed using Medium-Range Forecasts (MRF), Eta, Blackadar, Yonsei University (YSU), and Mellor–Yamada–Janjic (MYJ) during Typhoon Ewiniar in 2006 to investigate the optimal PBL parameterizations for predicting sea winds accurately. The horizontal distributions of winds were analyzed to discover the spatial features. The time-series analysis of wind speed from five sensitivity experimental cases was compared by correlation analysis with surface observations. For the verification of sea surface winds, QuikSCAT satellite 10-m daily mean wind data were used in root-mean-square error (RMSE) and bias error (BE) analysis. The MRF PBL using MM5 produced relatively smaller wind speeds, whereas YSU and MYJ using WRF produced relatively greater wind speeds. The hourly surface observations revealed increasingly strong winds after 0300 UTC, July 10, with most of the experiments reproducing observations reliably. YSU and MYJ using WRF showed the best agreements with observations. However, MRF using MM5 demonstrated underestimated winds. The conclusions from the correlation analysis and the RMSE and BE analysis were compatible with the above-mentioned results. However, some shortcomings were identified in the improvements of wind prediction. The data assimilation of topographical data and asynoptic observations along coast lines and satellite data in sparsely observed ocean areas should make it possible to improve the accuracy of sea surface wind predictions.     

Linkage of paraglacial processes from last glacial to recent inferred from Spituk sequence,Leh valley,Ladakh Himalaya

The paraglacial sequence in the Leh valley, Ladakh Himalaya preserves imprints of various processes active during deglaciation in the late phase of Last Glacial. In present work, a high resolution sedimentological record generated for Spituk is presented identifying aeolian episodes, mudflow events from Ladakh Range and debris flows extending from Zanskar Range across present Indus River. Two temporal phases of water ponding within Spituk Sequence are also identified. The seismites recorded at various stratigraphic depths and their association with the sediment facies signifies gravity induced process besides possible seismic activity as an added phenomena. Linkage between paraglacial processes since Last Glacial to Recent is tracked and evaluated.     

Environmental impact on groundwater of Maheshwaram Watershed,Ranga Reddy district,Andhra Pradesh

Maheshwaram watershed is situated in Ranga Reddy district of at a distance of about 30 km south of Hyderabad. The watershed has an area of 53 km² and has hard rock aquifers with semi-arid climate. The study area has been expanding at a fast pace and now has the distinction of being one of the fastest growing urban centers, facing the problem of groundwater depletion and quality deterioration due to the absence of perennial source of surface water and also due to over exploitation. Human activities involving industrial and agricultural development and the inadequate management of land and water resources have, directly or indirectly resulted in the degradation of environment viz. water and soil.     

What kind of countryside do the public want: community visions from Wales UK?

This paper assesses how far community led rural visions accord with the current thrust of rural planning policy delivery in the UK. Adapting conventional visioning methods, qualitative techniques were used on eight different communities across urban, exurban and rural Wales to elicit views relating to the kind of local countryside(s) that were desired. The results show that the communities’ visions reflect an emerging consensus around local countryside priorities: multifunctionality, integration, wider countryside protection, development based on need, and local distinctiveness according with the thrust of current planning policy at national and local levels. However, there is a clear dichotomy between this and the reality of what communities actually experienced in developments affecting their countryside. Here, universal criticism was encountered over the type, pace and scale of development, the lack of rural specificity and the failure to take account of local community needs and priorities. It is hypothesized that tensions between national and local politics and stakeholder power relations are playing a crucial role in distorting the delivery of town and country planning. It is recommended that rural policy delivery must become more “joined up” and rural proofed at national and local levels concomitant with a change in the operational culture of agencies at the forefront of rural delivery. Essentially, effective engagement of top down approaches synergising with bottom up community led ideas is long overdue.     

First- and second-order adaptation to natural hazards and extreme events in the context of climate change

This paper deals with coping and adaptation processes to natural hazards and (potential) climate change impacts. Selected response measures to natural hazards are critically reviewed with respect to the actual and potential consequences that these measures might imply for additional adaptation needs and changes within social-ecological systems. In this context, the author introduces the concept of first- and second-order adaptation processes in order to underline the cascade process that adaptation implies, the potentials for failure, and the limits of adaptation. Important aspects of first- and second-order adaptation processes as well as the issue of the limits of adaptation are illustrated based on observations and empirical work conducted in Vietnam. In its final part, the paper discusses the findings in light of selected theoretical approaches that might help to understand how stabilization and destabilization processes are influenced or even triggered by adaptation measures.     

Eoalpine tectonics of the Eastern Alps: implications from the evolution of monometamorphic Austroalpine units (Schneeberg and Radenthein Complex)

Monometamorphic metasediments of Paleozoic or Mesozoic age constituting Schneeberg and Radenthein Complex experienced coherent deformation and metamorphism during Late Cretaceous times. Both complexes are part of the Eoalpine high-pressure wedge that formed an intracontinental suture and occur between the polymetamorphosed Ötztal–Bundschuh nappe system on top and the Texel–Millstatt Complex below. During Eoalpine orogeny Schneeberg and Radenthein Complexes were south-dipping and they experienced a common tectonometamorphic history from ca. 115 Ma onwards until unroofing of the Tauern Window in Miocene times. This evolution is subdivided into four distinct tectonometamorphic phases. Deformation stage D1 is characterized by WNW-directed shearing at high temperature conditions (550–600°C) and related to the initial exhumation of the high-pressure wedge. D2 and D3 are largely coaxial and evolved during high- to medium-temperature conditions (ca. 450 to ≥550°C). These stages are related to advanced exhumation and associated with large-scale folding of the high-pressure wedge including the Ötztal-Bundschuh nappe system above and the Texel–Millstatt Complex below. For the area west of the Tauern Window, F2/F3 fold interference results in the formation of large-scale sheath-folds in the frontal part of the nappe stack (formerly called “Schlingentektonik” by previous authors). Earlier thrusts were reactivated during Late Cretaceous normal faulting at the base of the Ötztal–Bundschuh nappe system and its cover. Deformation stage D4 is of Oligo-Miocene age and accounted for tilting of individual basement blocks along large-scale strike-slip shear zones. This tilting phase resulted from indentation of the Southern Alps accompanied by the formation of the Tauern Window.     

Vibrational and thermodynamic properties of Ni<Subscript>3</Subscript>S<Subscript>2</Subscript> polymorphs from first-principles calculations

We have calculated the compressional, vibrational, and thermodynamic properties of Ni₃S₂ heazlewoodite and the high-pressure orthorhombic phase (with Cmcm symmetry) using the generalized gradient approximation to the density functional theory in conjunction with the quasi-harmonic approximation. The predicted Raman frequencies of heazlewoodite are in good agreement with room-temperature measurements. The calculated thermodynamic properties of heazlewoodite at room conditions agree very well with experiments, but at high temperatures (especially above 500 K) the heat capacity data from experiments are significantly larger than the quasi-harmonic results, indicating that heazlewoodite is anharmonic. On the other hand, the obtained vibrational density of states of the orthorhombic phase at 20 GPa reveals a group of low-frequency vibrational modes which are absent in heazlewoodite. These low-frequency modes contribute substantially to thermal expansivity, heat capacity, entropy, and Grüneisen parameter of the orthorhombic phase. The calculated phase boundary between heazlewoodite and the orthorhombic phase is consistent with high-pressure experiments; the predicted transition pressure is 17.9 GPa at 300 K with a negative Clapeyron slope of −8.5 MPa/K.