scholarly journals In-situ Real-time Field Imaging and Monitoring of Leaf Stomata by High-resolution Portable Microscope

2019 ◽  
Author(s):  
Prashant Purwar ◽  
Junghoon Lee
Keyword(s):  
High Resolution ◽  
Real Time ◽  
Stomatal Opening ◽  
Objective Lens ◽  
Lower Epidermis ◽  
Plant Hydraulics ◽  
Small Depth ◽  
Field Imaging

ABSTRACTStomata, functionally specialized micrometer-sized pores on the epidermis of leaves (mainly on the lower epidermis), control the flow of gases and water between the interior of the plant and atmosphere. Real-time monitoring of stomatal dynamics can be used for predicting the plant hydraulics, photosensitivity, and gas exchanges effectively. To date, several techniques offer the direct or indirect measurement of stomatal dynamics, yet none offer real-time, long-term persistent measurement of multiple stomal apertures simultaneously of an intact leaf in a field under natural conditions. Here, we report a high-resolution portable microscope-based technique for in situ real-time field imaging and monitoring of stomata. Our technique is capable of analyzing and quantifying the multiple lower epidermis stomal pore dynamics simultaneously and does not require any physical or chemical manipulation of a leaf. An upward facing objective lens in our portable microscope allows the imaging of lower epidermis stomatal opening of a leaf while upper epidermis being exposed to the natural environment. Small depth of field (~ 1.3 μm) of a high-magnifying objection lens assists in focusing the stomatal plane in highly non-planar tomato leaf having a high density of trichome (hair-like structures). For long-term monitoring, the leaf is fixed mechanically by a novel designed leaf holder providing freedom to expose the upper epidermis to the sunlight and lower epidermis to the wind simultaneously. In our study, a direct relation between the stomatal opening and the intensity of sunlight illuminating on the upper epidermis has been observed in real-time. In addition, real-time porosity of leaf (ratio between the areas of stomatal opening to the area of a leaf) and stomatal aspect ratio (ratio between the major axis and minor axis of stomatal opening) along with stomatal density have been quantified.

MARINE-EO project: Monitoring and forecast of eutrophication around fish farms, a Maliakos Gulf case (Eastern Mediterranean).

2021 ◽  
Author(s):  
Amandine Declerck ◽  
Matthias Delpey ◽  
Thibaut Voirand ◽  
Ioanna Varkitzi
Keyword(s):  
Water Quality ◽  
High Resolution ◽  
Real Time ◽  
Chlorophyll A ◽  
Satellite Observation ◽  
Risk Level ◽  
Fish Farms ◽  
Ocean Modelling ◽  
Monitoring And Forecasting

<p>Keywords: eutrophication; high resolution ocean modeling ; Chla satellite data ; biogeochemistry</p><p>Maliakos Gulf corresponds to mesotrophic waters that can reach eutrophic conditions and are occasionally subject to Harmful Algal Blooms (HAB) (Varkitzi et al. 2018). At the same time, it is an important fish farming and aquaculture production area. A large issue is thus related to the monitoring and forecasting of the risk of occurrence of algae blooms in the Gulf. For this purpose, the present study couples predictions from a high-resolution numerical ocean model with satellite observation to improve the monitoring and anticipation of threats for the local fish farms induced by occasional eutrophication.</p><p>This solution is developed in the frame of the MARINE-EO project (https://marine-eo.eu/). It combines satellite observation with high-resolution ocean modelling to provide detailed information as a support to fish farms management and operations. It is implemented in an operational platform, which provides continuous information in real time as well as short term predictions. The deployed solution uses CMEMS physical products as an input data and offers to refine this solution in order to provide a local information on site using a downscaling strategy. High resolution satellite products and ocean modelling allow to include the impact of local coastal processes on currents and water quality parameters to provide a proper monitoring and forecasting solution at the scale of a specific fish farm.</p><p>To model specific eutrophication processes, a NPZD (Nutrients-Phytoplankton-Zooplankton-Detritus) biogeochemical model is used. Included in the MOHID Water modelling system, the water quality module (Mateus, 2006) considering 18 properties: nutrients and organic matter (nitrogen, phosphorus and silica biogeochemical cycles), oxygen and organisms (phytoplankton and zooplankton) was deployed in the western Aegean Sea. The simulated chlorophyll a concentrations are used to compute a risk level for the eutrophication occurrence. To complete this indicator, another risk level was based on the eutrophication variation following Primpas et al. (2010) formulation. In addition to model forecasts, ocean color observations from the Sentinel-2 MSI and Landsat-8 OLI sensors are used to provide high resolution chlorophyll a concentrations maps in case of bloom events. The processing chain uses the sixth version of the Quasi-Analytical Algorithm initially developed by Lee et al. (2002) and an empirical relation based on a database built using the HydroLight software to compute chlorophyll a concentration.</p><p>Two past eutrophication events monitored in situ (Varkitzi et al. 2018) were studied to assess the accuracy of the developed tool. Although few in situ data were available on environmental input (as rivers flow and nutrient concentrations), it was possible using statistics to reproduce qualitatively these blooms. Finally, an operational demonstration was conducted during 2 months of the 2020 autumn season, to showcase real time monitoring and predictive perspectives.</p>

Microfluidic passive samplers for in situ collection of live aquatic protists

2014 ◽  
Vol 6 (20) ◽  
pp. 8350-8357 ◽  
Author(s):  
Grant M. Bouchillon ◽  
Jessica Furrer Chau ◽  
George B. McManus ◽  
Leslie M. Shor
Keyword(s):  
High Resolution ◽  
Passive Samplers ◽  
Aquatic Habitats ◽  
Long Term Observation ◽  
In Situ Collection

Examples of microfluidic passive samplers for collecting live protists from aquatic habitats. The samplers allow high-resolution, long-term observation of unstained protists by concentrating and isolating them in nanoliter-scale galleries.

scholarly journals LGHAP: a Long-term Gap-free High-resolution Air Pollutants concentration dataset derived via tensor flow based multimodal data fusion

2021 ◽  
Author(s):  
Kaixu Bai ◽  
Ke Li ◽  
Mingliang Ma ◽  
Kaitao Li ◽  
Zhengqiang Li ◽  
...  
Keyword(s):  
Environmental Management ◽  
High Resolution ◽  
Data Fusion ◽  
Air Pollutants ◽  
Big Data Analytics ◽  
Quality Data ◽  
Haze Pollution ◽  
Pm2.5 And Pm10

Abstract. Developing a big data analytics framework for generating a Long-term Gap-free High-resolution Air Pollutants concentration dataset (abbreviated as LGHAP) is of great significance for environmental management and earth system science analysis. By synergistically integrating multimodal aerosol data acquired from diverse sources via a tensor flow based data fusion method, a gap-free aerosol optical depth (AOD) dataset with daily 1-km resolution covering the period of 2000–2020 in China was generated. Specifically, data gaps in daily AOD imageries from MODIS aboard Terra were reconstructed based on a set of AOD data tensors acquired from satellites, numerical analysis, and in situ air quality data via integrative efforts of spatial pattern recognition for high dimensional gridded image analysis and knowledge transfer in statistical data mining. To our knowledge, this is the first long-term gap-free high resolution AOD dataset in China, from which spatially contiguous PM2.5 and PM10 concentrations were estimated using an ensemble learning approach. Ground validation results indicate that the LGHAP AOD data are in a good agreement with in situ AOD observations from AERONET, with R of 0.91 and RMSE equaling to 0.21. Meanwhile, PM2.5 and PM10 estimations also agreed well with ground measurements, with R of 0.95 and 0.94 and RMSE of 12.03 and 19.56 μg m−3, respectively. Overall, the LGHAP provides a suite of long-term gap free gridded maps with high-resolution to better examine aerosol changes in China over the past two decades, from which three distinct variation periods of haze pollution were revealed in China. Additionally, the proportion of population exposed to unhealthy PM2.5 was increased from 50.60 % in 2000 to 63.81 % in 2014 across China, which was then drastically reduced to 34.03 % in 2020. Overall, the generated LGHAP aerosol dataset has a great potential to trigger multidisciplinary applications in earth observations, climate change, public health, ecosystem assessment, and environmental management. The daily resolution AOD, PM2.5, and PM10 datasets can be publicly accessed at https://doi.org/10.5281/zenodo.5652257 (Bai et al., 2021a), https://doi.org/10.5281/zenodo.5652265 (Bai et al., 2021b), and https://doi.org/10.5281/zenodo.5652263 (Bai et al., 2021c), respectively. Meanwhile, monthly and annual mean datasets can be found at https://doi.org/10.5281/zenodo.5655797 (Bai et al., 2021d) and https://doi.org/10.5281/zenodo.5655807 (Bai et al., 2021e), respectively. Python, Matlab, R, and IDL codes were also provided to help users read and visualize these data.

High-temperature high-resolution in-situ microscopy of grain boundary migration and structure change

1990 ◽  
Vol 48 (4) ◽  
pp. 514-515
Author(s):  
Hideki Ichinose ◽  
Tokuji Kizuka ◽  
Yoichi Ishida
Keyword(s):  
High Temperature ◽  
High Resolution ◽  
Grain Boundary ◽  
High Stability ◽  
Boundary Migration ◽  
Structure Change ◽  
Objective Lens ◽  
Video Tape ◽  
Grain Boundary Migration

A high resolution high temperature specimen stage of 200kV HRTEM was newly designed and produced in order to investigate the physical and mechanical nature of materials at high temperature.The atomic process of silicon grain boundary migration and the structure change was successfully observed in-situ at 1000K by the new specimen stage.The high temperature specimen stage consists of a heating specimen holder, a high stability power supply and a high stability current controller. Heat is provided by an induction free double spiral coil heater which is made of tungsten. Excellent current stability, better than 10−6 , prevents the objective lens from the magnetic disturbance which is caused by heating current. The highest temperature of the specimen is designed to be 1100K. The accuracy of the temperature measurement is checked by the melting test of tin. In order to keep the high resolution of the microscope(JEM-200CX) at such high temperature as 1100K an objective lens is also newly designed and produced. Aberration constants of the new lens are respectively Cs=0.7mm and Cc=1.2mm. Resulted resolution at high temperature is as same level as the that of the original JEM-200CX at room temperature. Images are recorded by a video tape recorder.

scholarly journals Evaluation of snow extent time series derived from Advanced Very High Resolution Radiometer global area coverage data (1982–2018) in the Hindu Kush Himalayas

2021 ◽  
Vol 15 (9) ◽  
pp. 4261-4279
Author(s):  
Xiaodan Wu ◽  
Kathrin Naegeli ◽  
Valentina Premier ◽  
Carlo Marin ◽  
Dujuan Ma ◽  
...  
Keyword(s):  
Climate Change ◽  
High Resolution ◽  
Land Cover ◽  
Snow Cover ◽  
Area Coverage ◽  
Slope Aspect ◽  
Hindu Kush ◽  
Very High

Abstract. Long-term monitoring of snow cover is crucial for climatic and hydrological studies. The utility of long-term snow-cover products lies in their ability to record the real states of the earth's surface. Although a long-term, consistent snow product derived from the ESA CCI+ (Climate Change Initiative) AVHRR GAC (Advanced Very High Resolution Radiometer global area coverage) dataset dating back to the 1980s has been generated and released, its accuracy and consistency have not been extensively evaluated. Here, we extensively validate the AVHRR GAC snow-cover extent dataset for the mountainous Hindu Kush Himalayan (HKH) region due to its high importance for climate change impact and adaptation studies. The sensor-to-sensor consistency was first investigated using a snow dataset based on long-term in situ stations (1982–2013). Also, this includes a study on the dependence of AVHRR snow-cover accuracy related to snow depth. Furthermore, in order to increase the spatial coverage of validation and explore the influences of land-cover type, elevation, slope, aspect, and topographical variability in the accuracy of AVHRR snow extent, a comparison with Landsat Thematic Mapper (TM) data was included. Finally, the performance of the AVHRR GAC snow-cover dataset was also compared to the MODIS (MOD10A1 V006) product. Our analysis shows an overall accuracy of 94 % in comparison with in situ station data, which is the same with MOD10A1 V006. Using a ±3 d temporal filter caused a slight decrease in accuracy (from 94 % to 92 %). Validation against Landsat TM data over the area with a wide range of conditions (i.e., elevation, topography, and land cover) indicated overall root mean square errors (RMSEs) of about 13.27 % and 16 % and overall biases of about −5.83 % and −7.13 % for the AVHRR GAC raw and gap-filled snow datasets, respectively. It can be concluded that the here validated AVHRR GAC snow-cover climatology is a highly valuable and powerful dataset to assess environmental changes in the HKH region due to its good quality, unique temporal coverage (1982–2019), and inter-sensor/satellite consistency.

Practical aspects, experiences and strategies by using UV/VIS sensors for long-term sewer monitoring

2006 ◽  
Vol 1 (1) ◽  
Author(s):  
G. Gruber ◽  
J.-L. Bertrand-Krajewski ◽  
J. De Beneditis ◽  
M. Hochedlinger ◽  
W. Lettl
Keyword(s):  
Sample Preparation ◽  
Real Time ◽  
Simultaneous Measurement ◽  
Weather Conditions ◽  
Sewer Systems ◽  
Pros And Cons ◽  
Wet Weather ◽  
No Sample Preparation

An explosion-proof UV/VIS sensor has been available even in sewer systems for some years for simultaneous measurement of CODeq, filtered CODeq, TSSeq and nitrateeq. This sensor allows in-situ real-time measurements with no sampling, no sample preparation and no reagents. Three case studies are presented in this paper using this UV/VIS sensor for long-term sewer monitoring issues whereby two different installation strategies are applied. The pros and cons of both different installation solutions are compared and different calibration results during dry and wet weather conditions and long-term operational sewer monitoring experiences are given in this paper.

scholarly journals The International Soil Moisture Network: an open-source data hosting facility in support of meteorology and climate science

2021 ◽  
Author(s):  
Ivana Petrakovic ◽  
Irene Himmelbauer ◽  
Daniel Aberer ◽  
Lukas Schremmer ◽  
Philippe Goryl ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Real Time ◽  
International Cooperation ◽  
Land Surface ◽  
Prediction Models ◽  
Weather Prediction ◽  
Source Surface ◽  
Federal Institute

<p>The International Soil Moisture Network (ISMN, https://ismn.earth) is international cooperation to establish and maintain a unique centralized global data hosting facility, making in-situ soil moisture data easily and freely accessible (Dorigo et al., 2021). Initiated in 2009 as a community effort through international cooperation (ESA, GEWEX, GTN-H, GCOS, TOPC, HSAF, QA4SM, C3S, etc.), the ISMN is an essential means for validating and improving global satellite soil moisture products, land surface-, climate-, and hydrological models. <br><br>The ISMN is a widely used, reliable, and consistent in-situ data source (surface and sub-surface) collected by a myriad of data organizations on a voluntary basis.  The in-situ soil moisture measurements are collected, harmonized in terms of units and sampling rates, advanced quality control is applied and the data is then stored in a database and made available online, where users can download it for free. Currently, 71 networks are participating with more than 2800 stations distributed on a global scale and a steadily increasing number of user communities. Long term time series with mainly hourly timestamps from 1952 – up to near-real-time are stored in the database, including daily near-real-time updates. Besides soil moisture in our database are stored other meteorological variables as well (air temperature, soil temperature, precipitation, snow depth, etc.).<br><br>The ISMN provides benchmark data for several operational services such as ESA CCI Soil Moisture, the Copernicus Climate Change (C3S) and Global Land Service (CGLS), and the online validation tool QA4SM. ISMN data is widely used in a variety of scientific fields (e.g., climate, water, agriculture, disasters, ecosystems, weather, biodiversity, etc).<br><br>To validate the land surface representations of meteorological forecasting models soil moisture from the ISMN has often been used. The development of various generations of TESSEL models used both in the Integrated Forecasting Systems and reanalysis products of ECMWF, greatly profited from soil moisture and temperature data from the ISMN. Using ISMN data several studies assessed the soil moisture skill of the Weather Research and Forecasting Model (WRF) and assessed the forecast skill or new implementations of numerical weather prediction models.<br><br>We greatly acknowledge the financial support provided by ESA through various projects: SMOSnet International Soil Moisture Network, IDEAS+, and QA4EO.<br><br>To ensure a long-term funding for the ISMN operations, several ideas were perused together with ESA. A partner for this task could be found within the International Center for Water Resources and Global Change (ICWRGC) hosted by the German Federal Institute of Hydrology (BfG). <br><br>In this session, we want to give an overview and future outlook of the ISMN, highlighting its unique features and discuss challenges in supporting the hydrological research community in need of freely available, standardized, and quality-controlled datasets. </p>

scholarly journals From satellite altimetry to Argo and operational oceanography: three revolutions in oceanography

2013 ◽  
Vol 10 (4) ◽  
pp. 1127-1167 ◽  
Author(s):  
P. Y. Le Traon
Keyword(s):  
High Resolution ◽  
Real Time ◽  
Sea Level ◽  
Ocean Circulation ◽  
Satellite Altimetry ◽  
Large Scale ◽  
Global Ocean ◽  
Operational Oceanography ◽  
In Situ Observations

Abstract. The launch of the US/French mission Topex/Poseidon (T/P) (CNES/NASA) in August 1992 was the start of a revolution in oceanography. For the first time, a very precise altimeter system optimized for large scale sea level and ocean circulation observations was flying. T/P alone could not observe the mesoscale circulation. In the 1990s, the ESA satellites ERS-1/2 were flying simultaneously with T/P. Together with my CLS colleagues, we demonstrated that we could use T/P as a reference mission for ERS-1/2 and bring the ERS-1/2 data to an accuracy level comparable to T/P. Near real time high resolution global sea level anomaly maps were then derived. These maps have been operationally produced as part of the SSALTO/DUACS system for the last 15 yr. They are now widely used by the oceanographic community and have contributed to a much better understanding and recognition of the role and importance of mesoscale dynamics. Altimetry needs to be complemented with global in situ observations. In the end of the 90s, a major international initiative was launched to develop Argo, the global array of profiling floats. This has been an outstanding success. Argo floats now provide the most important in situ observations to monitor and understand the role of the ocean on the earth climate and for operational oceanography. This is a second revolution in oceanography. The unique capability of satellite altimetry to observe the global ocean in near real time at high resolution and the development of Argo were essential to the development of global operational oceanography, the third revolution in oceanography. The Global Ocean Data Assimilation Experiment (GODAE) was instrumental in the development of the required capabilities. This paper provides an historical perspective on the development of these three revolutions in oceanography which are very much interlinked. This is not an exhaustive review and I will mainly focus on the contributions we made together with many colleagues and friends.

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