Miracle-dz/UniFAR-FTUs huggingface dataset:
Measurements and characterization of particle size distributions in coastal waters

[1] The particle size distribution (PSD) plays a central role in understanding many facets of the aquatic ecosystem, yet it is rarely measured in field studies and no single method provides a complete description of the PSD. In this study, size distributions of diverse particle suspensions were measured using a laser diffractometer (LISST-100X), an electrical impedance particle sizer (Coulter Counter), and a particle imaging system (FlowCAM). All three instruments provided similar estimates of average particle size for suspensions of known standards. For broad polydisperse assemblages of particles a generally good agreement was found between the LISST and Coulter over a large portion of the size spectrum (from ∼1–3 μm to 50 μm), with the exception of suspensions exhibiting narrow features which were not accurately resolved with the LISST measurement. For featureless PSDs, however, the LISST provides an adequate proxy and has the capability for in situ measurements with high spatial and temporal resolution. We examined LISST field measurements from coastal regions within the context of a commonly used parameterization of the PSD. Analysis of nearly 5500 size distributions suggest that the average slope of the power law distribution for particles larger than 3 μm is −3.5. However, in many coastal waters this model provides a poor description of the PSD owing to the presence of significant peaks in the distribution. The combination of these data with Mie scattering calculations suggest that such departures from the idealized PSD can significantly impact the prediction of seawater optical properties.
A regional‐to‐global model of emission and transport of sea salt particles in the atmosphere

[1] A parameterization for the emission of sea-salt aerosol (SSA) particles is presented and its application in the SILAM dispersion modeling system for regional and global SSA simulations is discussed. The SSA production term is based on the parameterization of Monahan et al. and on experimental data from Martensson et al., and Clarke et al. The observational data were used to extend the Monahan et al. SSA emission flux to particles as small as 10 nm (dry particle diameter DP) and to account for water temperature and salinity. The result is an analytical formulation describing the SSA production fluxes for particles with Dp between 10 nm and 10 μm. This source function is implemented in the dispersion model SILAM and applied to compute the distribution of sea salt over the North Atlantic and Western Europe for the years 2000, 2003, 2007, 2009 and 2010, as well as globally for 2001 and 2008. The computed annual global production of SSA is between 6700 and 7400 Tg/year. Comparison of the SILAM near-surface SSA concentrations and its wet deposition with the in situ EMEP observations showed good agreement for summer periods while in winter time the model tends to under-estimate the wet deposition by a factor of ∼3. The underestimation is attributed to the coarse fraction (Dp > 10 μm) and the spume production mechanism, which were excluded from the analysis, to the wet deposition parameterization in SILAM and to the under-estimated precipitation amount in the input meteodata. The predicted vertically integrated aerosol optical depth (AOD) showed a close match with satellite observations over SSA-dominated areas.
QUANTIFYING ENDSCRAPER REDUCTION IN THE CONTEXT OF OBSIDIAN EXCHANGE AMONG EARLY PASTORALISTS IN SOUTHWESTERN KENYA

Abstract Mobile strategies are foundational components of nomadic pastoralist socio-economic organization in East Africa. Beginning around 3,000 BP, nomadic herders in southwestern Kenya had integrated the regular transport of obsidian across a 200 km landscape into these strategies. Pastoral Neolithic groups in the region relied on obsidian for the production of blade based toolkits. Viewed through an organization approach, the patterns of tool reduction and discard in the archaeological record may be used to infer dimensions of obsidian access, as perceived by early herding communities. In order to begin assessing the social and economic factors structuring obsidian access and use in this region, this study examines the intensity of obsidian endscraper reduction as a correlate for overall stresses on pastoralist obsidian supply. Several excavations in the 1970s and 1980s produced lithic assemblages from southwestern Kenya that were reexamined and sampled for this analysis. Using methods developed in forager contexts in other regions, there appear to be few differences in the intensity in tool use between sites. This pattern may indicate that communities across a large landscape had regular and consistent access to obsidians from distant sources. The study contributes to renewed interest in the Pastoral Neolithic in East Africa, and is situated within ongoing discussions of technological organization in global contexts.
Slope stability analysis by strength reduction

INTRODUCTION For slopes, the factor of safety F is traditionally de®ned as the ratio of the actual soil shear strength to the minimum shear strength required to prevent failure (Bishop, 1955). As Duncan (1996) points out, F is the factor by which the soil shear strength must be divided to bring the slope to the verge of failure. Since it is de®ned as a shear strength reduction factor, an obvious way of computing F with a ®nite element or ®nite difference program is simply to reduce the soil shear strength until collapse occurs. The resulting factor of safety is the ratio of the soil's actual shear strength to the reduced shear strength at failure. This `shear strength reduction technique' was used as early as 1975 by Zienkiewicz et al. (1975), and has since been applied by Naylor (1982), Donald & Giam (1988), Matsui & San (1992), Ugai (1989), Ugai & Leshchinsky (1995) and others. The shear strength reduction technique has a number of advantages over the method of slices for slope stability analysis. Most importantly, the critical failure surface is found automatically. Application of the technique has been limited in the past due to the long computer run times required. But with the increasing speed of desktop computers, the technique is becoming a reasonable alternative to the method of slices, and is being used increasingly in engineering practice. However, there has been little investigation of the accuracy of the technique. In this paper, factors of safety obtained with the shear strength reduction technique are compared to limit analysis solutions for a homogeneous embankment.
Fluorescence lidar method for remote monitoring of effects on vegetation

Plants constantly interact with environment, mainly, by means of photosynthesis and soil nutrition. The state of plant photosynthetic apparatus that reflects the general physiological state of a plant, can be analyzed remotely on a basis of laser-induced fluorescence using a fluorescence lidar. In this respect, a fluorescence lidar can be a technical means of remote sensing of the effects on vegetation including chemical soil pollution. Among a series of applications, of interest is development of a lidar technique for detecting the effects of oil products and mechanical disturbances. This paper is devoted to the application of the fluorescence lidar technique to monitoring mechanical and chemical impacts on the woody vegetation typical of Siberia. A physical basis of this technique is the red fluorescence of chlorophyll of green plants excited by the second harmonic (532 nm) of Nd:YAG laser. Red fluorescence of plants consists of two bands centered at 685 and 740 nm which is conditioned by functioning of two photosystems. As in situ experiments show, the indicated photosystems and, respectively, the fluorescence on these bands respond differently to feeding disturbances and mechanical impacts, making the increase in the fluorescence intensity informative. Time criteria of fluorescence characteristics were obtained at single and multiple effects on the vegetation. The paper describes a lidar system that meets the requirements for detecting the effects on vegetation.
Correlating seismicity parameters and subsidence in the Tokai region, central Japan

[1] We demonstrate that transients in subsidence rate in the Tokai area of central Japan correlate with changes in the rate and size distribution of earthquakes. Three largely independent seismic catalogs cover this region: National Research Institute for Earth Science and Disaster Prevention (NIED), Japanese Meteorological Agency (JMA), and Japan University Network Catalog (JUNEC). Comparing seismicity patterns between these three data sets offers a unique opportunity to verify seismicity anomalies based on independent sources. A study of data quality, magnitude reporting consistency, and consistency across the three data sources reveals that the NIED data for the period 1981–2002 are best suited for seismicity analysis. We spatially and temporally map seismicity rates, finding that a significant decrease in the earthquake rate of M ≥ 2.0 events coincides with an accelerated subsidence period; however, this anomaly disappears when including smaller magnitudes in the analysis. This relative quiescence of larger events can readily be explained when interpreting the transient in seismicity in the framework of a change in the earthquake size distribution, or b value. The background b value of about 0.8 increased in the period 1987.5–1989.5 to a value of b = 1.2, a highly significant change that can be confirmed in all three data sets. The correlation between subsidence and b value change is significant. Stress tensor inversions of focal mechanism data for the anomalous period show an increase in thrusting-type earthquakes. While a unique interpretation of the relationship between subsidence and b value is not possible, we propose that an increase in the locking stress, a “slow stick event,” is consistent with all observations.
Collapse and reorganisation of the Southern Ocean overturning under global warming in a coupled model

This study investigates the long‐term behaviour of the thermohaline circulation (THC) in the CSIRO climate model, under a scenario of transient increase of atmospheric (equivalent) CO2 concentration followed by a perpetual stabilisation at triple the initial level (3 × CO2). The North Atlantic Deep Water Formation (NADWF) declines substantially and the Antarctic Bottom Water Formation (AABWF) essentially ceases by the time of CO2 tripling. During the subsequent millennium of stable 3 × CO2, NADWF recovers slightly but the AABWF shows no sign of returning and the residual deep overturning dies away. Accelerating the convergence to equilibrium of the deep ocean under the 3 × CO2 condition, the global THC eventually reaches a near‐stable state with the entire ocean warming by about 7°C, NADWF fully recovered and AABWF partly re‐established. This result shows a possible new quasi‐equilibrium of the ocean under long‐term global warming induced by the anthropogenic CO2 increase.
Elastic moduli, pressure derivatives, and temperature derivatives of single‐crystal olivine and single‐crystal forsterite

Ultrasonic wave velocities in single-crystal forsterite (F) and single-crystal olivine (O) have been measured as a function of pressure and of temperature near ambient conditions. Shear and longitudinal velocities were measured in eighteen independent modes, so that each of the nine elastic constants could be calculated by at least two independent equations. The adiabatic stiffness constants cij (in Mb), their temperature derivatives dcij/dT (10−4 Mb/deg), and their pressure derivatives dCij/dP, are ij 11 22 33 44 55 66 23 31 12Cij (F) 3.284 1.998 2.353 0.6515 0.8120 0.8088 0.738 0.688 0.639 (O) 3.237 1.976 2.351 0.6462 0.7805 0.7904 0.756 0.716 0.664dcij/dT (F) 3.31 2.81 2.83 1.30 1.32 1.51 0.46 0.82 1.04 (O) 3.40 2.85 2.86 1.28 1.30 1.57 0.51 0.94 1.05dcij/dP (F) 8.47 6.56 6.57 2.12 1.66 2.37 4.11 4.84 4.67 (O) 7.98 6.37 6.38 2.17 1.64 2.31 3.76 4.48 4.74The density ρo and other isotropic properties including the adiabatic bulk modulus Ks, the shear modulus μ, the Poisson ratio σs, and their pressure and temperature derivatives (using the same dimensions as above) computed by the VRH (Voigt-Reuss-Hill) method are ρ Ks μ σs dKs/dT dμ/dT dσs/dT, 10−5 °C−1 dKs/dP dμ/dP dσs/dP(F) 3.224 1.286 0.811 0.240 −1.50 −1.30 0.93 5.37 1.80 0.42(O) 3.311 1.294 0.791 0.246 −1.56 −1.30 0.92 5.13 1.79 0.36
Lithospheric age dependence of Off‐Ridge Volcano production in the North Pacific

Data for numbers of seamounts on North Pacific Ocean crust of different age indicate that the production rate of new off-ridge seamounts (volcanoes) is proportional to the inverse of the square root of the age of the lithosphere. This observation is consistent with several hypotheses which have been offered to explain the origin of off-ridge oceanic volcanism and, in combination with petrologic and paleomagnetic evidence for small oceanic volcanoes, leads to a new self-consistent model for off-ridge volcanism. In this model, the production rate of off-ridge volcanoes is controlled primarily by the availability of fracture-zone conduit systems in the thickening lithosphere. In contrast, mantle plume or ''hotspot'' volcanoes may punch through the oceanic lithosphere. Decreasing production rate of off-ridge volcanoes on old oceanic lithosphere may be associated with decreasing extent of partial melting of chemically and isotopically heterogeneous mantle material.
Pollen productivity estimates strongly depend on assumed pollen dispersal

Past plant abundance may be reconstructed from pollen data if dispersal distances of pollen and pollen productivities of each taxon are known. Using surface sediment samples from small and medium sized, closed and near circular lakes from lowland Central Europe, we tested the validity of three pollen dispersal models by comparing empirical pollen data from each lake with simulated pollen data derived from applying various pollen dispersal models to vegetation data from rings situated up to 100 km from each site. Pollen assemblages simulated with a Lagrangian stochastic (LS) model best fit real pollen assemblages, simulations with the commonly used Prentice model on pollen dispersal underestimated the amount of pollen arriving from distances larger than 10 km and overestimated the differences in dispersal distances between lighter (Pinus) and heavier (Fagus, Picea) pollen grains. The LS model appeared to provide more appropriate simulations. Pollen productivity estimates (PPEs) calculated for the data set showed that the choice of the dispersal model has great impact on the results. If derived with the Prentice model, PPEs for Fagus and Picea are three times higher than with the LS model. Studies on pollen productivities thus need to consider the apparent limitations of the Prentice model. We suggest an alternative approach, which uses simulations instead of the extended R-value model, to calculate PPEs. The approach is flexible in the use of dispersal functions and produced consistent results for two independent data sets from small and medium sized lakes.
Potassium-calcium exchange in some New Zealand soils

The preference of some New Zealand soils to retain potassium over calcium under simulated field conditions has been measured by using Gaines and Thomas selectivity coefficients. All samples showed a preference for potassium over calcium (and magnesium), although the soils contained much more exchangeable calcium than exchangeable potassium. The preference for potassium decreased as more potassium was added to the samples. Oxidic, allophanic and ultic soils had the least preference for potassium; brown soils, formed mainly in loess, had the greatest preference, and this was probably due to the presence of many potassium-selective sites on vermiculite and mica clays in the soils. The results suggest that calcium, rather than potassium, is likely to be leached from all of the soils tested. This was consistent with data from laboratory leaching experiments using an allophanic soil.
Ground‐Water Modeling in a Southwestern Alluvial Basin

A two-dimensional finite-difference computer code was used to model the ground-water flow system in an alluvial basin in southwest New Mexico. A three-step approach was used to determine the transmissivity distribution for the model. First, values of the natural logarithm of transmissivity (In T) were interpolated from existing data using the kriging technique. This interpolation scheme also produced a map of standard deviations of the kriging errors. Second, a conventional flow net was drawn from steadystate water levels with the aid of the kriged hydraulic head distribution. Third, the approximate transmissivity map, the standard deviation map of the kriged In T values, and flow net were used to select the segment of each streamtube where transmissivity was known with greatest certainty (smallest In T kriging error). Then, transmissivities in other segments of the stream tubes were calculated from Darcy's Law. This distribution, when input to the numerical model, did not have to be altered appreciably during the calibration for a steady-state and seven-year transient period. Most of the transient calibration was accomplished by adjusting storage coefficients. Considering the uncertainty in the available pumping data, very good agreement was found between observed and predicted water levels during a four-year model verification period.
Through‐Water Close Range Digital Photogrammetry in Flume and Field Environments

Measurement of the structure of gravel‐bed river surfaces is crucial for understanding both bed roughness and the sediment entrainment process. This paper describes the use of close range digital photogrammetry to measure and monitor change occurring in submerged river gravel‐beds in both flume and field environments. High‐resolution digital elevation models (DEMs) were obtained and two‐media (through air and water) techniques were used to correct for the e.ects of refraction at the air/water interface. Although suitable refractive models have been developed, the use of proprietary software to generate DEMs automatically introduces the problem of how to re‐establish collinearity. A simple refraction correction algorithm based upon analytical geometry was developed and is described. This algorithm was designed for use after initial DEM acquisition and allows any photogrammetric software package to be used for data acquisition. Application of this algorithm led to improvements in DEM accuracy by reducing the systematic, depth‐dependent bias caused by refraction
Mangrove colonization: mangrove progression over the growing Pak Phanang (SE Thailand) mud flat

Abstract A combination of remote sensing techniques and in situ measurements along a chronosequence was used to elucidate the rate of progression of the mangrove forest in the Pak Phanang Bay (SE Thailand), a large bay with an extended and rapidly accreting mud flat. The examination of black and white aerial photographs of the forest in 1966, 1974, 1989 and 1995, and satellite images in 1985, 1990 and 1994 revealed that the mangrove forest located in the eastern bank of the bay was progressing over the mud flat. The rate of progression was estimated, from examination of changes in the position of the forest edge with time in the series of images, to average 38·6 m year −1 over the 28-year interval encompassed by the images. Mangrove progression rates were fastest between 1966 and 1974 and slowest between 1974 and 1985, remaining uniform at about 30 m year −1 thereafter. The in situ examination of vegetation along transects in the area of fastest mangrove progression showed an average progression rate of 53·12±5·86 m year −1 , quite similar to the estimate (48·4 m year −1 ) derived from remote sensing techniques for the area where the transects were surveyed. Avicennia alba was found to dominate the vegetation at the progressing edge of the mangrove, followed by Sonneratia caseolaris , with Rhizophora apiculata being present only occasionally. The fast colonization of A. alba over the mud flat was supported by a large export flux of mangrove propagules from the channels draining the mangrove forest, which averaged 3715±920 and 1900±808 fruits day −1 in each of the channels examined. Extrapolation of the long-term mean mangrove progression rate observed along the eastern bank of the Pak Phanang Bay suggested that this mangrove forest will increase by 33 ha year −1 . These results provide evidence that natural mangrove colonization can be a rapid process if sufficient propagules of the pioneer species ( A. alba and S. caseolaris ) are available, and point, therefore, to alternative management plans to promote and enhance natural colonization processes.
NONPRICE WATER CONSERVATION PROGRAMS AS A DEMAND MANAGEMENT TOOL 1

ABSTRACT: Water providers nationwide are implementing nonprice conservation measures such as education, public information, appliance retrofit and ordinances, with the expectation that these programs will reduce residential water demand. However, little empirical information exists on the effectiveness of nonprice conservation programs in reducing water demand. Previous econometric studies indicate these programs have had minimal impact. We examine the types and number of major nonprice conservation programs that have been implemented during an 11‐year period in seven cities in the southwestern United States. A cross sectional, monthly time series residential water demand model, with parameters to control for variation in prices, temperature, precipitation and other factors, was used to empirically investigate the effectiveness of nonprice conservation programs in reducing water demand. We found significant reductions in use ranging between 1.1 percent and 4.0 percent per program. Because of the lack of information, we were unable to distinguish the effectiveness of individual or specific types of programs. Beyond finding that nonprice programs can be effective in reducing demand, questions regarding the efficiency and benefits to be achieved by conservation remain. As a step towards separating and evaluating the effects of individual programs, program benefits and efficiency, we recommend that utilities maintain more detailed and consistent information regarding the implementation of their nonprice programs.
Radar technique potential for evaluating water content of cover concrete

ABSTRACT Many of the pathologies of concrete require the presence of water to develop. We used the direct transmitter-receiver radar wave to determine the moisture of the cover concrete. This wave is of great interest because it does not require the presence of reflectors and, as it propagates through the subsurface, it can provide information on the cover concrete. We showed that there is a linear relationship, independent of the concrete, between the water content and (i) the propagation velocity of the direct wave and (ii) its attenuation. The use of the radar technique on a reinforced concrete bridge enabled us to validate the influence of water content variation on radar waves.
Town Population Change 1971-1986: Patterns and Distributional Effects

Population change was traced for census town-size groups for the years 1971-1981 and 1981-1986. The 1970s were characterised by widespread growth; medium-size towns in particular increased their share of the total population and some redistribution from inner areas to suburbs took place. The years 1981-1986 were, by contrast, marked by lower growth rates, selective town decline and considerable continuity in distribution patterns.