Miracle-dz/UniFAR-FTUs huggingface dataset:
Lacustrine sedimentological and geochemical records for the last 170 years of climate and environmental changes in southeastern China

Reconstruction of modern climate and environmental changes in east Asia using inland natural climate archives can provide valuable insights on decadal–multidecadal climate and environmental patterns that are probably related to both natural and anthropogenic forcing. Here we investigated an 89‐cm‐long sediment core (TH1) from Tian Lake, southeastern China, for sedimentological, physical and geochemical parameters in order to understand climate and environmental changes for the latest two centuries. 137Cs‐ and 210Pb‐based age models show that the fine sand–coarse silt‐dominated core contains ~170 years (c. AD 1842–2011) of continuous sedimentation. Sediments with fine sands, low MS values, high water content, high TOC content and a high C:N ratio from c. AD 1842 to 1897 suggest intense hydrological conditions and strong runoff in the catchment, probably because of a humid climate. From AD 1897 to 1990, sediments with very fine sand and coarse silt, high MS values, low water content and unchanged TOC and C:N ratios indicate normal hydrological conditions and in‐lake algae‐derived organic matter. During this interval, the chemical weathering indicators show stronger weathering conditions compared with sediments deposited during AD 1842–1897, supporting the dominance of weathered surface soil input in the earlier interval and physical erosion dominance in the later period, respectively. Since AD 1990, the continuous decrease of geochemical proxies suggests human‐interacted Earth surface processes in the catchment of Tian Lake. A PCA revealed four dominant geochemical controlling factors – detrital input, trophic status, grain size and early diagenesis –, accounting for 26, 20, 18 and 16% of total variance, respectively. This study for the first time provides lacustrine geochemical evidence for the most recent two centuries of climate and environmental changes in coastal southeastern China, a region that is currently undergoing an inversion of critical zone, i.e. an overturning of its soil profile, owing to swift modernization.
The influence of salinity and flocculation upon the acquisition of remanent magnetization in some artificial sediments

SUMMARY A range of redeposition experiments with both magnetite and maghemite grains embedded in kaolinite or quartz has revealed a significant, non-linear relationship between salinity and the intensity and magnitude of the inclination error of the depositional remanent magnetization (DRM). Increasing DRM intensities and inclination errors were observed for salinities between 0–1 g/l. A dramatic reduction in intensity as well as in inclination error, appears for salinities above ca 2 g/l. Although there is a negligible effect on intensity of salinity for concentrations above 3 g/l, a significant inclination error persists over this range of salinities, approaching less than 5° at concentrations larger than 30 g/l. The observed relationships are suggested to reflect mechanisms related to flocculation. The results are probably not generally applicable to natural sediments, since floc formation in nature usually involves organic compounds.
Upper ocean heat and freshwater budgets in the eastern Pacific warm pool

[1] This study focuses on upper ocean budgets of heat and freshwater, which yield estimates of net surface heat flux and rainfall minus evaporation. The budgets are based on a 19 day ship survey conducted as part of the Eastern Pacific Investigation of Climate Processes in the Coupled Ocean-Atmosphere System 2001 in September 2001. Underway measurements included temperature and salinity sections from an undulating platform, SeaSoar, and horizontal currents from an acoustic Doppler current profiler along a 146 × 146 km survey pattern centered near 10°N, 95°W in the eastern Pacific warm pool. Additional measurements from a second ship at the center of the survey pattern included radar backscatter from rainfall, air-sea fluxes, and vertical profiles of temperature, salinity, microstructure, and horizontal velocity. Satellite measurements of surface height, temperature, and rainfall were also analyzed. The heat budget of 20 and 25 m surface layers indicated that storage, advection, turbulent transport, and penetrative solar radiation were all significant components of the heat budget with a net surface cooling of 41 W m−2 estimated as a residual, which agreed with atmospheric measurements (30 W m−2). The precipitation rate from the freshwater budget was 29 mm d−1, which was in excellent agreement with in situ measurements on both ships and in good agreement with satellite estimates for the same period. Lateral transports of heat and salt were influenced by an anticyclonic eddy in the survey area, and it is suggested that anticyclonic eddies, which form near the Central American coast, may carry anomalously warm sea surface temperature toward the west and become preferential sites for heavy rainfall.
Influence of the small intertidal seagrass Zostera novazelandica on linear water flow and sediment texture

Abstract The influence of a small intertidal seagrass, Zostera novaz.elandica (Setchell), on tidal current velocities and sediment texture was studied at Harwood, Otago Harbour, New Zealand. Tidal current velocities were substantially reduced inside the Z. novazelandica patch compared to velocities above the patch (3.7 times greater) and outside it (2.5 times greater), causing a low‐flow environment among the 12‐cm‐tall seagrass. Current velocities combined over one tidal cycle occupied a much wider range outside ( 1.2‐A.b cms‐1) and above ( 1.9–7.1 cm s‐1) the seagrass patch than inside (0.1–1.8 cm s‐1) indicating slower and less variable water flow. Suspended mud (<0.063 mm) settled to the bottom in this low‐energy environment and was protected from resuspension by seagrass cover, indicated by significantly elevated amounts of mud inside the seagrass patch (1.1%) compared to outside (0.4%). These results indicate that Z. novazelandica may reduce water flow and accumulate finer sediment sizes to a lesser extent than larger subtidal seagrass species.
Stomatal Responses to Drought Stress and Air Humidity

Water is one of the most important substances for both plant and animal survival. Plants require water for photosynthesis, nutrient uptake and transportation as well as cooling (Farooq et al., 2009). Plants are sessile organisms and in contrast to most animals they are unable to move when the environment becomes unfavorable. Accordingly, plants have to be able to respond and adapt to the local environmental changes. Since water is essential for plant survival, the ability to tolerate water stress is crucial. To be able to grow plants need to take up water from the soil and CO2 from the atmosphere and use it in photosynthesis. This is done by CO2 uptake through the stomatal pore, where water is simultaneously transpired. Water transpiration drives the water uptake by the roots and transport through the xylem. When the stomata are open CO2 is taken up while water is transpired. When the stomata are closed little CO2 is taken up and the transpiration is lowered. By opening and closing the stomata plants can regulate the amount of water lost, by sacrificing CO2 uptake, when the environmental conditions are unfavorable. Water stress can be defined as reduced water availability; either by water scarcity (drought) or osmotic stress (high salt concentrations) or water logging; too much water. Water stress may reduce photosynthesis, respiration and ion uptake, change the metabolic and growth patterns in the plant and in severe cases result in plant death (Jaleel et al., 2009a). In nature water stress is common either for long or short periods of time, depending on the local climate. Most plants therefore have some adaptation or response to enhance the growth and survival rate during water stress and subsequent recovery. In agriculture and horticulture drought stress is one of the major problems, causing major crop losses every year as well as loss of aesthetic value in ornamentals. In agriculture crop loss is due to reduced numbers of tillers, spikes and grains per plant and reduced grain weight (Farooq et al., 2009). With the global human population rapidly increasing, simultaneously as water scarcity increases, the loss of crop will be even more serious than before. The discovery and development of stress tolerant crops to avoid yield loss during water stress is therefore very important. In the greenhouse industry, energy saving for economic profit is important to be able, but it also affects the plants. To reduce the amount of energy needed for CO2 and heating in the greenhouses, energy-efficient semi-closed
Detecting climate variations and change: New challenges for observing and data management systems

Abstract Several essential aspects of weather observing and the management of weather data are discussed as related to improving knowledge of climate variations and change in the surface boundary layer and the resultant consequences for socioeconomic and biogeophysical systems. The issues include long-term homogeneous time series of routine weather observations; time- and space-scale resolution of datasets derived from the observations; information about observing systems, data collection systems, and data reduction algorithms; and the enhancement of weather observing systems to serve as climate observing systems. Although much has been learned from existing weather networks and methods of data management, the system is far from perfect. There are several vital areas that have not received adequate attention. Particular improvements are needed in the interaction between network designers and climatologists; operational analyses that focus on detecting and documenting outliers and time-dependent biases wit.
Incorporating Family Function into Chronic Pain Disability: The Role of Catastrophizing

Background. Observers' responses to pain are recently investigated to more comprehensively explain chronic pain (CP) and disability. However, the role of family context, defined as interference in roles, communication, and problem-solving, and how (i.e., through which mechanisms) these variables contribute to CP related disability have yet to be examined. Objectives. The aim of the present study is to examine family context in relationship to pain catastrophizing, fear of movement, and depression and its role in understanding CP disability. Three different models were examined. Methods. A total sample of 142 patients with musculoskeletal chronic pain was recruited to examine the role of fear of movement, pain intensity, pain catastrophizing, and depression in relationship to family functioning as predictors of disability. Results. Findings indicated that two models showed acceptable fit, but one of them revealed superior fit indices. Results of the model with superior fit indices indicated that family dysfunction may contribute to catastrophic thinking, which, in turn, contributes to patients' disability through increasing fear of movement and depression. Discussion. The current study provides further support for the notion that the impact of emotional and cognitive variables upon CP-related disability can be better understood when we consider the social context of pain patients and family function in particular.
Effects of viscosity and bottom friction on recirculating flows

A recent set of coastal experiments (Pattiaratchi et al., 1987), found that the horizontal eddy Reynolds number did not adequately describe the wakes found in the lee of coastal islands. Other flow parameters formulated on bottom friction were found to be much better at describing these wakes. In this paper it is suggested that these findings are caused by the extraction of energy from the flow due to bottom friction, which is the net result of the vertical viscous transfer of momentum through the water column to the seabed. This is in contrast to the horizontal viscous transfer of momentum which results in negligible energy loss to the coast, because of the far larger horizontal scales. It is hypothesized that this difference results in fundamentally different flow regimes and this hypothesis is investigated both analytically and numerically. Conditions for the existence of steady zones of barotropic recirculation under the influence of both horizontal viscosity and bottom friction in the wake behind a bluff body are examined analytically. It is found that such steady recirculation requires the presence of horizontal viscosity and is hindered by the loss of energy due to bottom friction. A numerical model is used to verify and quantify this analytical result for the case of two-dimensional flow around a circular cylinder, and it is concluded that an appropriate bottom friction number, based on the ratio of scales of the nonlinear and bottom friction terms, may often govern the nature of the recirculation in the lee of coastal islands, instead of the eddy Reynolds number based on horizontal eddy viscosity, as is sometimes assumed.
Collisions Between Platforms and Ships in Norway in the Period 2001-2010

Since 1982, 115 collisions have been reported on the Norwegian Continental Shelf, with varying degree of severity. In the period 2001–2010 there have been 26 reported collisions. None of the collisions has caused loss of lives or personnel injuries. The economic consequences however have been significant, especially one collision in 2009. This paper will give statistical summaries of the events, and compare the development of events with previous periods. The focus will be on the six most severe cases, describing each case, the damage and emphasise the most common causes of these events.Copyright © 2011 by ASME
Identification of a Kdn biosynthesis pathway in the haptophyte Prymnesium parvum suggests widespread sialic acid biosynthesis among microalgae

Sialic acids are a family of more than 50 structurally distinct acidic sugars on the surface of all vertebrate cells where they terminate glycan chains and are exposed to many interactions with the surrounding environment. In particular, sialic acids play important roles in cell–cell and host–pathogen interactions. The sialic acids or related nonulosonic acids have been observed in Deuterostome lineages, Eubacteria, and Archaea but are notably absent from plants. However, the structurally related C8 acidic sugar 3-deoxy-d-manno-2-octulosonic acid (Kdo) is present in Gram-negative bacteria and plants as a component of bacterial lipopolysaccharide and pectic rhamnogalacturonan II in the plant cell wall. Until recently, sialic acids were not thought to occur in algae, but as in plants, Kdo has been observed in algae. Here, we report the de novo biosynthesis of the deaminated sialic acid, 3-deoxy-d-glycero-d-galacto-2-nonulosonic acid (Kdn), in the toxin-producing microalga Prymnesium parvum. Using biochemical methods, we show that this alga contains CMP–Kdn and identified and recombinantly expressed the P. parvum genes encoding Kdn-9-P synthetase and CMP–Kdn synthetase enzymes that convert mannose-6-P to CMP–Kdn. Bioinformatics analysis revealed sequences related to those of the two P. parvum enzymes, suggesting that sialic acid biosynthesis is likely more widespread among microalgae than previously thought and that this acidic sugar may play a role in host–pathogen interactions involving microalgae. Our findings provide evidence that P. parvum has the biosynthetic machinery for de novo production of the deaminated sialic acid Kdn and that sialic acid biosynthesis may be common among microalgae.
Estimation of evapotranspiration using remotely sensed land surface temperature and the revised three-temperature model

Evapotranspiration (ET) is one of the most important land surface processes for terrestrial ecosystems because it strongly relates to both the energy balance and the mass balance of these ecosystems. Although there are many ground based approaches to estimate ET, it is still a challenge to estimate ET by remote sensing for most applications. The three-temperature model (3T model) is a recently developed approach used to estimate ET based on ground measurement. Compared with other conventional ET estimation algorithms, fewer input parameters are required in the 3T model. Therefore, it shows good potential for remote sensing application. In this study, we aimed to extend the 3T model for remote sensing application and to validate its accuracy. First, algorithms to extend the 3T model for estimating the regional ET of mixed landscapes were proposed. Then, two case studies were presented using Landsat Thematic Mapper (TM)/Landsat Enhanced Thematic Mapper Plus (ETM+) images. Thereafter, the Bowen ratio energy balance method (BREBM) and the residual method of the energy balance equation (RMEBE) were adopted to validate the performance of the revised 3T model. Results showed that the absolute error of the mean daily ET estimated by the BREBM and the revised 3T model was 0.23 mm d−1, whereas between the RMEBE and the revised 3T model it was 0.07 mm d−1. This accuracy is acceptable for most application purposes. The revised 3T model demonstrates the ability to remotely sense actual regional evapotranspiration.
Influence of Initial Conditions on Summer Precipitation Simulations over the United States and Mexico

Abstract The impact of initial conditions on summer precipitation over North America for July–September was examined by comparing long-term simulations of the Atmospheric Model Intercomparison Project (AMIP) runs with the ensemble simulations (SIMUs) initialized at the end of June each year. Both types of simulations use the observed SSTs as boundary conditions, and hence, the differences are a result of the initial conditions. Experiments were performed using the NCEP Global Forecast System (GFS) T126L28 model with 28 vertical levels. Over the monsoon core region, the model has the correct relationship between evaporation (E) and soil moisture and the T126 model has enough horizontal resolution to simulate the moisture transport from the Gulf of California. Over the Great Plains, the model has dry and warm biases. These biases are larger in the AMIP runs in comparison with the SIMU. Two major model errors contribute to the biases: 1) the deep soil layer (10–200 cm) is far too dry and does not have enough.
Investigation of ice‐wedge infilling processes using stable oxygen and hydrogen isotopes, crystallography and occluded gases (O2, N2, Ar)

The source and mechanism of infill of ice wedges of various ages (modern to Pleistocene) were examined for sites in the western Arctic. Several techniques were employed, including stable O‐H isotope and crystallographic analyses of the ice, and gas composition (O2, N2 and Ar) analyses of air entrapped in the ice. The results indicate that climatic and site‐specific conditions may influence the source of infilling during ice‐wedge growth, so that wedge ice in wet and dry environments exhibits different characteristics. For example, Vault Creek tunnel (Alaska) ice wedges, dating from the Late Pleistocene, a cold and dry period, preserved stable O‐H isotopes and gas compositions similar to those expected for ice formed by snow densification. In contrast, ice wedges from the Old Crow region (Yukon), dating from the Late Holocene, preserved isotopic and gas compositions more comparable with those expected for ice formed by the freezing of liquid water. In both ice‐wedge types, the δ(O2/Ar) values are much lower than both dissolved and atmospheric values, which may be due to the respiration of microorganisms living within ice bubbles or interstitial water at the grain boundaries. The elevated δ18OO2 (up to 16‰) of the occluded gases supports the occurrence of microbial respiration. However, the δ(N2/Ar) values do not appear to have been affected by biological processes, and as such are reflective of the infilling processes. Copyright © 2010 John Wiley & Sons, Ltd.
el modelo de ayudas directas en la PAC post-2013: análisis de impactos de escenarios potenciales

Desde su introduccion en 1992, las ayudas directas se han perfilado como uno de los principales instrumentos de apoyo al sector agrario de la UE. Este trabajo analiza potenciales escenarios de convergencia de las ayudas directas en la PAC post-2013. Se utiliza para ello el modelo CAPRI, que permite representar el funcionamiento de los mercados agroalimentarios a escala global asi como incorporar las medidas de politica agraria a nivel regional. Los resultados indican que un pago unico mas nivelado tendria impactos minimos a nivel global de la UE pero conllevaria efectos redistributivos considerables, tanto entre regiones como entre Estados Miembros.
THE EFFECTS OF TIMING OF GRAZING ON PLANT AND ARTHROPOD COMMUNITIES IN GRASSLANDS OF SOUTHWEST MONTANA

Grassland plants have co-evolved with native ungulate grazers for millions of years, but over the last 100 years there has been a shift towards grazing by domestic livestock in North America. Many of the grazing-induced changes in plant and arthropod communities depend on how the grazing regime is implemented. Timing of grazing is one component of the grazing regime that is less well understood than grazing intensity and type of grazer, but is predicted to have important implications for plant and higher trophic level responses. The purpose of this study was to experimentally assess how timing of grazing affected plant and arthropod communities in high-elevation grasslands of southwest Montana. We designed a 2year field experiment that manipulated cattle grazing by implementing two grazing initiation dates, one beginning in mid-June and the other in mid-July. We compared plant (biomass and height) and arthropod characteristics (density and biomass of orders) across two years that differed in cumulative precipitation. Grazing reduced total plant biomass, forb biomass, and plant height with little to no recovery regardless of timing of grazing. The density of the most dominant arthropod order, Hemiptera, was reduced in both grazing treatments. By comparing end of season plant responses to grazing, we found that total plant biomass was unaffected in the drier year while forb biomass was unaffected in the wetter year. Many end of season arthropod responses were reduced by grazing in both study years. Although both grazing treatments reduced many plant and arthropod characteristics, grazing earlier in the growing season may impact higher trophic levels that are reliant on the presence of forbs and Hemiptera earlier in the growing season. These results have important implications for meeting conservation grazing objectives and for how timing of grazing may influence food availability for grassland-associated avian species of concern, in particular, smaller passerines.
Satellite detection of orographic gravity‐wave activity in the winter subtropical stratosphere over Australia and Africa

Orographic gravity‐wave (OGW) parameterizations in models produce waves over subtropical mountain ranges in Australia and Africa that propagate into the stratosphere during austral winter and deposit momentum, affecting weather and climate. Satellite sensors have measured stratospheric GWs for over a decade, yet find no evidence of these waves. So are parameterizations failing here? Here we argue that the short wavelengths of subtropical OGWs place them near or below the detection limits of satellite sensors. To test this hypothesis, we reanalyze nine years of stratospheric radiances from the Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite during austral winter, applying new averaging techniques to maximize signal‐to‐noise and improve thresholds for OGW detection. Deep climatological enhancements in stratospheric OGW variance over specific mountain ranges in Australia and southern Africa are revealed for the first time, which exhibit temporal and vertical variations consistent with predicted OGW responses to varying background winds.