Yuanzhi Zhang

Chinese Academy of Sciences | CAS

The fish catch in natural upwelling areas, which accounts for only 0.1% of the ocean surface, accounts for more than 40% of the world’s catch. The Zhoushan fishery, which is the largest fishery in China, is mainly formed by a coastal upwelling that features a low temperature. The upwelling in the study area (29.5–31.5° N, 121.5–123.5° E) is a vital...

Several studies have documented that during ‘green tide’ events, comprising green macroalgae blooms in aquatic ecosystems, dissolved inorganic phosphorus (DIP) levels remain relatively steady despite the absorption of a large amount of DIP. In this study, surface sediment samples and a sediment core were extracted using a modified sequential extrac...

The Xinyanggang River in Yancheng City, one of the essential rivers entering the Yellow sea, has imported abundant pollutants to the coast of Jiangsu Province. Trace elements (Cr, Ni, Cu, Zn, As, Rb, Sr, Mo, Pb, Th, U, Sc, Ga, Se, Zr, Nb, and Sn) in surface sediments in the Xinyanggang River were measured to analyze the spatial distribution, risk a...

Spatial distribution information offers a valuable resource for the growing research on evaluating and managing aquaculture and the mechanism of its interaction with the environment, especially concerning landside clustering aquaculture ponds (LCAP). However, studies aimed at obtaining data on global LCAP distribution remains limited. This study co...

Sea surface temperature (SST), a critical parameter of the global ocean–atmosphere system, is an essential element in the study and in the application of marine science. Satellite–infrared observations currently represent the only available method for continuous, large-scale observation of SST. Although passive microwave observations are not blocke...

It is crucial to investigate the distribution and origin of black carbon (BC) in the environment for evaluating human inputs and developing pollution control strategies. This study analyzed BC in coastal river sediments from Haizhou Bay, Eastern China. The concentrations (dry weight) of the BC, char, soot, and total organic carbon (TOC) in coastal...

The in situ lunar regolith explorations of Chang’E 3, 4, and 5 landing sites provide an essential reference for lunar research based on microwave radiometer (MRM) data from Chang’E 1 and 2 satellites. To eliminate the influence of the brightness temperature with latitude and highlight the relationship between the brightness temperature and the luna...

Lunar cryptomare records both early-stage mare volcanisms and large-scale impact cratering, which can provide important information about the thermal evolution of the Moon. We built a mixing dielectric constant model to represent the cryptomare deposits mixed by highland debris and mare deposits, and the proper radiative transfer simulation was con...

Because the Pan-Arctic melt pond significantly influences the mass balance of sea ice, analyzing changes in the Pan-Arctic melt pond can offer insights into the Arctic sea ice and environment. In this study, the MODIS level 2 surface reflectance product (MOD09A1) was used to calculate variability and trends in the Pan-Arctic melt pond fraction (MPF...

Synthetic aperture radar interferometry (InSAR) is a technology that has been widely used in many areas, such as topographic mapping, land and resource survey, geological exploration, disaster prevention and mitigation, volcanic and seismic monitor and so on. Landslide, as a representative geohazard, include a wide range of phenomena involving down...

The dynamic process of the wetland can reflect its impact on the environment, and finding a balance point supporting harmonious coexistence between man and nature has become an issue of increasing concern. On the basis of previous studies that have focused on local coastal wetlands, the temporal and spatial changes and driving forces of wetlands in...

Over the past few decades, development in China (including Shenzhen) has been led by the State, meaning that the government has been responsible for major decisions in urban construction and management. However, the current enormous contradiction between people’s demand for livability and Shenzhen’s unequal and inadequate urban development means th...

Mare Frigoris is the fifth largest and almost northernmost mare located on the near side of the Moon. Mare Frigoris has an elongated shape, with a length of approximately 1500 km and a width of approximately 200 km, which makes it susceptible to becoming contaminated by the impact ejecta from the nearby highlands. Comparatively speaking, microwave...

Offshore aquaculture is critical for a marine fishery economy. The spatial distribution of aquaculture that characterizes it plays a vital role in the sustainable development of marine resources and the protection of the marine environment. In recent years, China’s aquaculture has developed rapidly; specifically, the scale of aquaculture has dramat...

Hong Kong and Shenzhen have entirely different land-use development policies, resulting in a disparity in the increase rate of impervious surface area. Impervious surface estimation is a significant method for evaluating urbanization, so that countries and cities can deal with their growing populations. The impervious surface area was estimated thr...

Monitoring the surface deformation is of great significance, in order to explore the activity and geophysical features of the underground deep pressure source in the volcanic regions. In this study, the time series surface deformation of the Changbaishan volcano is retrieved via Sentinel-1B SAR data, using the SBAS-InSAR method. The main results ar...

Optical remote sensing is limited to clouds and rain. It is difficult to obtain ground object images in severe weather. Microwave remote sensing can penetrate clouds and rain to obtain ground object images. Therefore, this paper combines optical and microwave data to analyze the time and space of the green-tide in the Yellow Sea in 2021. Compared w...

Because Eurasian snow water equivalent (SWE) is a key factor affecting the climate in the Northern Hemisphere, understanding the distribution characteristics of Eurasian SWE is important. Through empirical orthogonal function (EOF) analysis, we found that the first and second modes of Eurasian winter SWE present the distribution characteristics of...

In this study, strong internal tides were observed on the continental slope northeast of Taiwan Island. Owing to the lack of long-term observations, these tides’ intraseasonal variability and the impact of the Kuroshio Current remain unclear. This study aimed to fill in the gaps using one-year continuous mooring observations, satellite data and ana...

Due to the cloud blocking, the research on the responses of upper ocean to typhoons using satellite data is greatly affected. At present, most of the solutions are based on lower time resolution data or composite satellite data. In this paper, multi-source satellite data were fused by weighted average method and reconstructed through the Data INter...

Vegetation is a land-use type that attracting growing attention in urban studies. Extraction of urban vegetation information can be achieved by land-use/land-cover (LULC) classification. It has been proved that SAR remote sensing provides complementary information in LULC classification. However, how the complementary information from SAR features...

Being significant to the coastal sustainability, mangrove forests have decreased at an alarming rate over the past decades, under various pressures from both natural and anthropogenic forces, while urbanization has been widely recognized as one major factor for the dramatic areal mangrove loss. China has experienced rapid urbanization, particularly...

Arctic Ocean surface circulation plays an important role in the global ocean circulation system. In recent years, its position and velocity have been changing constantly, attracting increasing attention. The cause of this change, however, is still a matter of disagreement. In this paper, we use empirical orthogonal function analysis (EOF) to analyz...

We used deep learning networks to establish a relationship model among MODIS daily surface reflectance product (MOD09GA) and Arctic melt ponds fraction (MPF), ice fraction (IF), and open water fraction (OWF). We applied this model to MODIS 8-day surface reflectance (MOD09A1) to derive Arctic 8-day MPF and SIF (SIF as the sum of IF and MPF). The res...

The stomata of Suaeda salsa are closed and the photosynthetic efficiency is decreased under conditions of water–salt imbalance, with the change to photosynthesis closely related to the chlorophyll fluorescence parameters of the photosystem PSII. Accordingly, chlorophyll fluorescence parameters were selected to monitor the growth status of Suaeda sa...

Canadian emergency management planners have historically ignored the self-motivated evacuation procedures of people who cannot initially choose the safest evacuation areas. In densely developed urban areas, open spaces can be seen as ideal evacuation areas and should thus be included in shelter planning. In this study, the public open spaces in Gre...

As the capital city of China, Beijing has experienced unprecedented economic and population growth and dramatic impervious surface changes during the last few decades. An application of the classification method combining the spectral and textural features based on Random Forest was conducted to monitor the spatial and temporal changes of Beijing’s...

Urban vegetation can regulate ecological balance, reduce the influence of urban heat islands, and improve human beings' mental state. Accordingly, classification of urban vegetation types plays a significant role in urban vegetation research. This paper presents various window sizes of completed local binary pattern (CLBP) texture features classify...

Urban vegetation can regulate ecological balance, reduce the influence of urban heat islands, and improve human beings’ mental state. Accordingly, classification of urban vegetation types plays a significant role in urban vegetation research. This paper presents various window sizes of completed local binary pattern (CLBP) texture features classify...

Floodplain wetlands in the China side of the Amur River Basin (CARB) undergone consistent decreases because of both natural and anthropogenic drivers. Monitoring floodplain wetlands dynamics and conversions over long-time periods is thus fundamental to sustainable management and protection. Due to complexity and heterogeneity of floodplain environm...

Based on Landsat 8 remote sensing images, a combination of an unsupervised classification algorithm and artificial review was used to extract areas for Chinese offshore raft and cage aquaculture in 2018. The results of the extraction showed that China’s 2018 coastal zone raft aquaculture area comprised 194,110 ha, of which the province having the l...

This paper reports on monitored Suaeda salsa spectral response to salt conditions in coastal wetlands, using spectral measurements and remotely sensed algorithms. Suaeda salsa seedlings were collected from the Dafeng Elk National Nature Reserve (DENNR) in Jiangsu Province, China. We treated 21 Suaeda salsa seedlings planted in pots with 7 different...

In this paper, we applied the re-analysis data cobe-SST (cobe-sea surface temperature) and Global Land Data Assimilation System (GLDAS) surface soil moisture (SM) data from 1961 to 2011 by using regional correlation analysis and time series causality analysis to trace annual variations in and identify the abnormal relationship of sea surface temper...

In recent decades, many algorithms have been developed for the retrieval of water quality parameters using remotely sensed data. However, these algorithms are specific to a certain geographical area and cannot be applied to other areas. In this study, feature-orientated principal component (PC) selection, based on the Crosta method and using Landsa...

Archaeological sites are facing serious threats from environmental changes in the background of urban sprawl. More efforts are needed to enhance the cognition of human–environment interactions for better conservation. Under the traditional geomantic view, the environmental preference involved was presented to guide ancient life. In this study, we a...

Typhoon storm surge research has always been very important and worthy of attention. Less is studied about the impact of tropical cyclone size (TC size) on storm surge, especially in semi-enclosed areas such as the northern East China Sea (NECS). Observational data for Typhoon Winnie (TY9711) and Typhoon Damrey (TY1210) from satellite and tide stat...

Polarimetric Synthetic Aperture Radar (SAR) has powerful capability in marine oil spill detection since it could distinguish clean sea surface from mineral oil spill and false alarms as biogenic thin films. As an alternative to fully polarimetric (FP) SARs, which provide complete scattering information, compact polarimetric (CP) SARs transmit a pol...

Based on satellite and analysis data and in situ observations acquired during May 23, 2017 to May 19, 2018, the spatiotemporal variations of the along-slope counter-flow off northeastern Taiwan were investigated. It was observed that the along-slope counter-flow in the subsurface layer was uplifted and lowered significantly during the study period....

In order to understand the response mechanism between plant stress, physiological indicators and hyperspectral indices, pot experiments were conducted on Suaeda salsa seedlings collected from a coastal wetland area to reveal the effects of salt stress on the physiological indicators and reflectance spectra of Suaeda salsa at the canopy and leaf lev...

Wetlands are one of the world’s most important ecosystems, playing an important role in regulating climate and protecting the environment. However, human activities have changed the land cover of wetlands, leading to direct destruction of the environment. If wetlands are to be protected, their land cover must be classified and changes to it monitor...

Olivine formation is directly related to Mg/Fe content. It is also significant in estimating the geological evolution of the moon. In this study, an estimation model of relative Mg number (Fo#) for lunar olivine was presented through multiple linear regression statistics. Sinus Iridum, the Copernicus Crater, and the pyroclastic deposit in the volca...

Aquaculture is one of the fastest growing animal food production sectors mainly developed in fertile coastal areas. Monitoring and mapping of aquaculture ponds are of utmost importance for the sustainable management of coastal ecosystems. In this study, an integrated updating and object-based classification approach was developed to generate maps o...

In this study, we applied the empirical orthogonal function (EOF) to analyze the anomalous characteristics of the summer Antarctic sea ice. Through correlation analysis, it is found that two strong signals existed in the spring Indian Ocean. These two signals constitute the Indian Ocean dipole (IOD). Although the IOD often occurs with El Niño-South...

Apollo basin is located within the large South Pole–Aitken (SPA) basin. The study on Apollo basin will provide interesting information about the basic geologic issues about the lunar farside. In this paper, the normalized brightness $(T_{B})$ temperature $(nT_{B})$ maps and the $T_{B}$ difference $(dT_{B})$ maps are generated with the Chang...

The rapid expansion of Porphyra yezoensis aquaculture in China has changed the sea surface landscape and caused inefficient sea-area usage. Thus, there is urgent to reasonably explore and utilize marine resources, protect marine ecology, and regulate the magnitude of sea-area usage. We monitored the spatial distribution of Porphyra yezoensis aquacu...

As a typical rapid-development seaport area in coastal cities, such as Caofeidian, the study on the spatiotemporal changes of urban land use and its surrounding rural areas is valuable and significant in reference to the future urban planning and land policies in similar coastal areas of China or other countries. Based on satellite images, this res...

Given the extensive spread and ecological consequences of exotic Spartina alterniflora (S. alterniflora) over the coast of mainland China, monitoring its spatiotemporal invasion patterns is important for the sake of coastal ecosystem management and ecological security. In this study, Landsat series images from 1990 to 2015 were used to establish mu...

Information about the soil quality of different land-use types and topographies is essential for the sustainable development, utilization, and protection of soil resource in coastal areas. In this study, representative topsoil samples were collected from Liandao Island, China, and soil water content (SWC), soil bulk density (BD), total nitrogen (TN...

In this study, we applied the 1988–2017 monthly average sea ice concentration data from the Met Office Hadley Centre and the 1988–2017 monthly average reanalysis data from the National Centers for Environmental Prediction/Department of Energy (NCEP/DOE) Reanalysis II to analyze the relationship between the winter precipitation in the Barents and Ka...

Chang'E lunar microwave sounder (CELMS) data provide a potential way to understand the thermophysical features of the shallow lunar crust. In this study, four typical Copernican craters, including Copernicus, Aristarchus, Tycho, and Jackson, have been selected and their brightness temperature $(T_{B})$ performances are evaluated with the CE-2 CEL...

Locations used to validate extraction results from remote sensing images are typically ground rock samples. However, remotely sensed image pixels are 30 m ² with mixing spectra. Rock samples cannot fully represent extraction results on an image. Here, alteration information associated with the Águas Claras, Brazil iron deposit was analysed using a...

Hydrocarbon micro-seepage can result in vegetation spectral anomalies. Early detection of spectral anomalies in plants stressed by hydrocarbon micro-seepage could help reveal oil and gas resources. In this study, the origin of plant spectral anomalies affected by hydrocarbon micro-seepage was measured using indoor simulation experiments. We analyze...

Soil plays an important role in coastal wetland ecosystems. The estimation of soil organic matter (SOM), total nitrogen (TN), and total carbon (TC) was investigated at the topsoil (0–20 cm) in the coastal wetlands of Dafeng Elk National Nature Reserve in Yancheng, Jiangsu province (China) using hyperspectral remote sensing data. The sensitive bands...

Three typhoon events were selected to examine the impact of energy transformation on near-inertial oscillations (NIOs) using observations from a subsurface mooring, which was deployed at 125° E and 18° N on 26 September 2014 and recovered on 11 January 2016. Almost 16 months of continuous observations were undertaken, and three energetic NIO events...

Mangroves are valuable ecosystems that have been protected and restored for decades in China. However, little is known about achievements of China's mangrove conservation efforts. This study aims to analyze the effectiveness of these efforts by presenting long-term dynamics of mangrove forests areal extent at the national scale. To achieve this goa...

Plant invasion imposes significant threats to biodiversity and ecosystem function. Thus, monitoring the spatial pattern of invasive plants is vital for effective ecosystem management. Spartina alterniflora (S. alterniflora) has been one of the most prevalent invasive plants along the China coast, and its spread has had severe ecological consequence...

In this paper, we analyzed the effect of SST on the precipitation of coastal areas of the eastern China. The relationship between the precipitation and SST of different seasons based on CMDC's monthly precipitation data and NOAA's SST data from 1979 to 2016 was calculated. Analysis on the links between precipitation and SST has shown a significant...