Fang Shen

East China Normal University | ECNU · State Key Laboratory of Estuarine and Coastal Research

Sea surface currents (SSC) play a pivotal role in material transport, energy exchange, and ecosystem dynamics in coastal marine environments. While traditional methods to obtain wide-range SSC, such as satellite altimetry, often struggle with limited performance in coastal regions due to waveform contamination, deriving SSC from sequential ocean co...

In the first part of this paper series (Sun et al., 2023), we developed an ecological model that partitions the total chlorophyll-a concentration (Chl-a) into three phytoplankton size classes (PSCs), pico-, nano-, and microplankton. The parameters of this model are controlled by sea surface temperature (SST), intended to capture shifts in phytoplan...

Long time series of spatiotemporally continuous phytoplankton functional type (PFT) data are essential for understanding marine ecosystems and global biogeochemical cycles as well as for effective marine management. In this study, we integrated artificial intelligence (AI) technology with multisource marine big data to develop a spatial–temporal–ec...

Plain Language Summary Marine heatwaves (MHWs) are described as an abnormal and prolonged increase of ocean temperatures. These events may occur in all the oceans, and are becoming more frequent than before. Such increase in water temperature might not be tolerated by organisms, which must need to adapt themselves to the new environmental condition...

Long time series of spatiotemporally continuous phytoplankton functional type (PFT) products are essential for understanding marine ecosystems, global biogeochemical cycles, and effective marine management. In this study, by integrating artificial intelligence (AI) technology with multi-source marine big data, we have developed a Spatial–Temporal–E...

River sediments play a critical role in sustaining deltaic wetlands. Therefore, concerns are raised about wetlands’ fate due to the decline of river sediment supply to many deltas. However, the dynamics and drivers of suspended sediment near deltaic coasts are not comprehensively assessed, and its response to river sediment supply changes remains u...

The coastal environment is characterized by high, multi-scale dynamics and the corresponding observations from a single remote sensing sensor are still facing challenges in achieving both high temporal and spatial resolution. This study proposed a spatiotemporal fusion model for coastal environments, which could fully enhance the efficiency of remo...

Turbidity is one of the key elements affecting the underwater light field and nutrient cycling. Turbidity monitoring can provide a scientific basis for pollution prevention, control, and early warning of river and lake water quality. The typical rivers and lakes in the demonstration zone of the Yangtze River Delta were taken as the study area. The...

In estuarine-coastal-shelf seas, Particulate Organic Carbon (POC) shows the highest turnover rates of any organic carbon pool on the planet, playing a key role in the biological carbon pump. Compared with open ocean, estuarine and coastal waters are affected by large river inputs and show high hydrodynamic variability, which results in a mixture of...

Accurate monitoring of the spatial-temporal distribution and variability of phytoplankton group (PG) composition is of vital importance in better understanding of marine ecosystem dynamics and biogeochemical cycles. While existing bio-optical algorithms provide valuable information, relying solely on satellite ocean color data remains insufficient...

The ocean plays a central role in modulating the Earth’s carbon cycle. Monitoring how the ocean carbon cycle is changing is fundamental to managing climate change. Satellite remote sensing is currently our best tool for viewing the ocean surface globally and systematically, at high spatial and temporal resolutions, and the past few decades have see...

Phytoplankton play a central role in the planetary cycling of important elements and compounds. Understanding how phytoplankton are responding to climate change is consequently a major question in Earth Sciences. Monitoring phytoplankton is key to answering this question. Satellite remote sensing of ocean colour is our only means of monitoring phyt...

HY-1C/D both carry a coastal zone imager (CZI) with a spatial resolution of 50 m and a swath width of 950 km, two observations can be achieved in three days when two satellites operating in a network. Accurate atmospheric correction is the basis for quantitative inversion of ocean color parameters using CZI However, atmospheric correction in estuar...

Because of the large diversity of case 2 waters ranging from extremely absorbing to extremely scattering waters and the complexity of light transfer due to external terrestrial inputs, retrieving main biogeochemical parameters such as chlorophyll-a or suspended particulate matter concentration in these waters is still challenging. By providing opti...

Because of the large diversity of case 2 waters ranging from extremely absorbing to extremely scattering waters and the complexity of light transfer due to external terrestrial inputs, retrieving main biogeochemical parameters such as chlorophyll-a or suspended particulate matter concentration in these waters is still challenging. By providing opti...

Synthetic aperture radar (SAR) signal can penetrate clouds and some vegetation canopies in all weather, and therefore, provides an important measurement tool for change detection and sustainable development of coastal wetland environments and ecosystems. However, there are a few quantitative estimations about the spatiotemporal coherence change wit...

An algorithm is proposed for consecutive retrieval of aerosol optical depth (AOD) and total suspended solid (TSS) concentration in turbid coastal water using a shortwave infrared band and a visible band. MODIS band 7 (∼2.1 μm) was used to retrieve the AOD in turbid coastal water, as the top-of-atmosphere reflectance in this band is more sensitive t...

Phytoplankton group composition is complex and highly variable in coastal waters. Given that different taxonomic groups have different pigment signatures, which in turn impact the light absorption spectra of phytoplankton, the absorption spectral‐based approach has the potential for distinguishing phytoplankton groups. Using a large dataset of in s...

Suspended sediments in the estuary play an important role in regulating the erosion-accretion and shaping the geomorphological patterns. Yet, it can be strongly impacted by the human activities. Constructions of basin and estuarine engineering in the Yangtze River Estuary (YRE), including constructions of Three Gorges Dam (TGD) further upstream of...

The suspended particulate matter (SPM) concentration (unit: mg l⁻¹) in surface waters is an essential measure of water quality and clarity. Satellite remote sensing provides a powerful tool to derive the SPM with synoptic and repeat coverage. In this study, we developed a new global SPM algorithm utilizing the remote sensing reflectance (Rrs(λ)) at...

During late 2019 and early 2020, Australia experienced one of the most active bushfire seasons that advected large emissions over the adjacent ocean. Herein, we present a comprehensive research on mixed atmospheric aerosol particulate pollution emitted by wildfires in the atmosphere and the ocean. Based on a wide range of physical and biochemical d...

The variation in suspended sediment concentration (SSC) has an important impact on the protection of estuarine shoal wetlands and the maintenance of waterways. Typhoons (tropical cyclones), one of the most severe meteorological disasters, frequently occur along the southeastern coasts of China and substantially affect the spatial-temporal distribut...

Intertidal wetlands are dynamic geomorphological areas located at the land-sea interface and perform multiple ecosystem functions. Owing to increased human activities, intertidal wetlands have been subjected to dramatic changes in recent decades; therefore, high-resolution monitoring of wetland topography is critical to its management. However, sat...

Phytoplankton cell size is a useful ecological indicator for evaluating the response of phytoplankton community structure to environmental changes. Ocean‐color remote observations and algorithms have allowed us to estimate phytoplankton size classes (PSCs) at decadal scale, helping us to understand their trends under ocean warming. Here a large dat...

High-turbidity water is a common feature in the estuary and inner shelf. Sediment suspension functions as a modulator that directly influences the interactions among nutrients, phytoplankton and other related ecosystem variables. A physical-biological coupling model system was applied to examine the impact of sediment front on interactions among on...

Phytoplankton species composition research is key to understanding phytoplankton ecological and biogeochemical functions. Hyperspectral optical sensor technology allows us to obtain detailed information about phytoplankton species composition. In the present study, a transfer learning method to inverse phytoplankton species composition using in sit...

The continental shelf seas of China (CSSC) broadly encompass the Bohai Sea, the Yellow Sea, and the East China Sea and exhibit highly variable optical properties. Accurate satellite estimates of particulate organic carbon (POC) remain challenging because optimal proxies for remotely sensed POC are largely obscure in these optically complex coastal...

The Changjiang River discharges huge amounts of nutrients, which cause frequent harmful algal blooms off its estuary. By analyzing historical and in situ observational data, this study aimed to determine the distribution and physical controls of these blooms. The results indicated that phytoplankton bloomed within the 30–50 m isobaths south of the...

In this study, cross-comparisons of the reflectance at the top of atmosphere (ρTOA), atmospherically corrected water-leaving reflectance (Rrs), and suspended sediment matter (SPM) concentration derived from three high spatial resolution sensors (Landsat-8/OLI, Sentinel-2A/MSI and GF-1/WFV) were conducted. The purpose was to examine the consistency...

The intensity data recorded by a terrestrial laser scanner (TLS) contain spectral characteristics of a scanned target and are mainly influenced by incidence angle and distance. In this study, an improved implementable method is proposed to empirically correct the intensity data of long-distance TLSs. Similar to existing methods, the incidence angle...

Terrestrial laser scanners (TLSs) can provide accurate and high-resolution data by measuring the distances (ranges) between the scanned points and the scanner center using time-of-flight or phase-shift-based methods. Distance measurement accuracy is of vital importance in TLSs and mainly influenced by instrument mechanism, atmospheric conditions, s...

Phytoplankton size classes (PSCs) is of great significance for exploring marine ecological and biogeochemical processes. Remote sensing of PSCs has been successfully applied to open oceans; however, it is still quite limited for optically complex coastal oceans. In this study, the entire continental shelf sea of China including Bohai Sea (BS), Yell...

Evidence of water reflectance saturation in extremely turbid media is highlighted based on both field measurements and satellite data corrected for atmospheric effects. This saturation is obvious in visible spectral bands, i.e., in the blue, green and even red spectral regions when the concentration of suspended particulate matter (SPM) reaches the...

A new network of hyperspectral radiometers is being developed for radiometric validation of satellite missions. This network follows closely the AERONET-OC federation concept [Zibordi et al, 2009] but uses the TRIOS/RAMSES hyperspectral radiometer. The instrument system consists of one radiance and one irradiance sensor on a pointing robot, control...

Suspended particulate matter (SPM) concentrations ([SPM]) in the Yangtze estuary, which has third-order bifurcations and four outlets, exhibit large spatial and temporal variations. Studying the characteristics of these variations in [SPM] is important for understanding sediment transport and pollutant diffusion in the estuary as well as for the co...

Distribution, migration and transformation of chromophoric dissolved organic matter (CDOM) in coastal waters are closely related to marine biogeochemical cycle. Ocean color remote sensing retrieval of CDOM absorption coefficient (a g (λ)) can be used as an indicator to trace the distribution and variation characteristics of the Changjiang diluted w...

Phytoplankton cell size is an important property that affects diverse ecological and biogeochemical processes, and analysis of the absorption and scattering spectra of phytoplankton can provide important information about phytoplankton size. In this study, an inversion method for extracting quantitative phytoplankton cell size data from these spect...

Mapping of suspended sediment concentration (SSC) can be achieved from the modern space-based optical sensors such as MODIS, MERIS, SeaWiFS, and GOCI using reliable atmospheric correction and SSC algorithms. We have developed two different atmospheric correction algorithms, namely, modified near-infrared―short-wave infrared (MNIR-SWIR) and analytic...

Remote sensing-based retrieval of the concentrations of water components relies largely on the accuracy of the atmospheric correction. Although a variety of atmospheric correction algorithms have been developed for turbid waters, the water-leaving reflectance is still underestimated in extremely turbid waters, such as in the Changjiang (Yangtze) es...

The purpose of this research is to improve the retrieval accuracy for the suspended sediment concentration (SSC) from in situ and satellite remote sensing measurements in turbid East China estuarine and coastal waters. For this aim, three important tasks are formulated and solved: 1) an estimation of remote-sensing reflectance spectra Rrs(λ) after...

The Multispectral Wide Field of View (WFV) camera on the Chinese GF-1 satellite, launched in 2013, has advantages of high spatial resolution (16 m), short revisit period (4 days) and wide scene swath (800 km) compared to the Landsat-8/OLI, which make it an ideal means of monitoring spatial-temporal changes of Suspended Particulate Matter (SPM) in l...

Development and validation of the surface suspended sediment concentration (SSC) models derived from the surface remote-sensing reflectance spectra [ Rrs(λ)] are important in satellite monitoring of estuarine and coastal waters. Seven empirical and seven semianalytical spectral reflectance models for evaluation of the surface SSC were compared with...

The 2SeaColor model (Salama & Verhoef, 2015) was proposed to analytically retrieve the diffuse attenuation coefficient (Kd) from remote sensing reflectance (Rrs), but its parameterization was based on approximations and subjected to large uncertainties. In this study, we present an improvement on the parameterization equations in the inverse scheme...

A comprehensive acoustic retrieval algorithm to investigate suspended sediment is presented with the combined validations of Acoustic Doppler Current Profiler (ADCP) and Optical Backscattering Sensor (OBS) monitoring along seven cross-channel sections in the high-turbidity North Passage of the Changjiang Estuary, China. The realistic water conditio...

Simulating the sediment transport in a high-turbidity region with spatially varying bed properties is challenging. A comprehensive strategy that integrates multiple methods is applied here to retrieve the critical shear stress for erosion, which plays a major role in suspended sediment dynamics in the Changjiang Estuary (CE). Time-series of sea sur...

A development and validation of the models on the base of the surface remote-sensing reflectance (Rrs) spectra for evaluation of the water quality parameters is an important part of satellite monitoring of inland, estuarine, and coastal waters. In this study, tenths of empirical and semi-analytical spectral reflectance models for evaluation of the...

Proc. VIII Int. Conf. "Current Problems in Optics of Natural Waters" ONW`2015. St-Petersburg, Russia, 8-12 September, 2015.

Waters in the Yangtze estuary and adjacent coastal ocean are optically complex and various in space and time distributions. Through conducting multiyear in situ measurements of water components and constituents and of their optical properties, we built and compared several bio-optical models adapted for turbid coastal waters, which were used for ob...

Phytoplankton dominant species and their light absorption properties during the blooms occurred in August 2013 in adjacent waters of the Changjiang Estuary were analyzed. The results showed that phytoplankton blooms broke out in 10 out of 34 investigation stations, among which diatom blooms occurred in 6 stations while 3 stations were predominated...

Based on the analysis of classified remote sensing images of the Yangtze Estuarine wetlands of 1980–2010, landscapes of the wetlands (Chongming Dongtan, Nanhui Biantan and Jiuduansha) in 2020 under three different scenarios (ecological protection, current trend and intensified reclamation) were predicted using the Dyna-CLUE and CA models. Results s...

The objective of this study was to evaluate the adaptability of the UBD microorganism on the biodegradation of three kinds of different wastewater as one of the applications of bio-augmentation technique in lab-scale batch experiments by directly adding UBD into the bioreactor. After biodegradation, the removal of chemical oxygen demand was lower t...

Spectral mixture analysis (SMA) has been extensively adopted in estimating sub-pixel impervious surface fractions. As a key step of SMA, endmember extraction has a big impact on the reliability of unmixing result. Due to the difficulty in extracting spectrally pure pixels using traditional methods, SMA is seldom applied to coarse-resolution imagery...

Light absorption properties of colored dissolved organic matter (CDOM) in adjacent waters of the Changjiang Estuary were investigated during the summer of 2013. CDOM absorption showed a substantial portion of the total absorption and clearly dominant among most investigation stations. It generally decreased from the northwest to the southeast, whic...

Range Doppler velocities derived from the Envisat advanced synthetic aperture radar (ASAR) wide swath images are analyzed and assessed against the numerically simulated surface current fields derived from the finite volume coastal ocean model (FVCOM) for the Changjiang Estuary. Comparisons with the FVCOM simulations show that the European Space Age...

The direct to diffuse incoming irradiance ratio q (or, alternatively, the contribution d E of the incoming diffuse irradiance into the total incoming irradiance) is an important parameter for modeling such optical properties as the underwater average cosine for the downwelling irradiance and transmittances through or reflectances from layers in the...

Radiative transfer modelling in atmosphere, water, and on the air-water surface was used to create an algorithm and computer code for satellite monitoring Chinese estuarine and coastal waters. The atmospheric part of the algorithm is based on the Reference Evaluation of Solar Transmittance (REST) model for calculation of optical properties of the a...

The original stress damage of the pumice lightweight aggregate concrete was examined via repeatedly stress loading enforcement and the "quick frost method". The relative dynamic modulus of elasticity and the mass loss rate were used as evaluation indicators. The antifreezethaw performance of lightweight aggregate concrete was analyzed at various da...

The (Pb0.70Ba0.26Sr0.04)(Zr0.52Ti0.48)O3 (PBSZT) piezo ceramics were prepared by the roll formation and solidstate reaction process. The microstructure and phase compositions of the ceramics were investigated by scanning electron microscopy and Xray diffraction. The relationships between dielectric properties (CT, tanδ) and electric field strengthe...