The inventories of nutrients in the surface water and large phytoplankton( > 69 microm) were analyzed from the data set of JERS ecological database about a typical coastal waters, the Jiaozhou Bay, China, from 1960s for N, P and from 1980s for Si. By examining long-term changes of nutrient concentration, calculating stoichiometric balance, and comparing diatom composition, Si limitation of diatom production was found to be more possible. The possibility of Si limitation was from 37% in 1980s to 50% in 1990s. Jiaozhou Bay ecosystem is becoming serious eutrophication, with notable increase of NO2-N, NO3-N and NH4-N from 0.1417 micromol/L, 0.5414 micromol/L, 1.7222 micromol/L in 1960s to 0.9551 micromol/L, 3.001 micromol/L, 8.0359 micromol/L in late 1990s respectively and prominent decrease of Si from 4.2614 micromol/L in 1980s to 1.5861 micromol/L in late 1990s; the nutrient structure is controlled by nitrogen; the main limiting nutrient is probably silicon; because of the Si limitation the phytoplankton community structure has changed drastically.
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Environ Monit Assess
January 2025
Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China.
The study of land cover dynamics and the valuation of ecosystem services in coastal cities is pivotal for guiding sustainable urban development and conserving natural resources amidst the unique challenges posed by their geographical and ecological contexts. This study utilizes a 30 m × 30 m land use/cover change (LUCC) dataset to elucidate the spatiotemporal evolution of LUCC and ecosystem service value (ESV) and the trade-offs and synergistic relationships among ecosystem services in the coastal city of Qingdao under three different scenarios over the past 35 years and in the future based on the dual perspective of the past-future by using the equivalent factor approach (EFA), the PLUS model, and Spearman's rank correlation coefficient. The findings reveal a pronounced expansion in built-up areas in Qingdao from 1985 to 2020, with a concomitant significant reduction in cropland, leading to a fluctuation in the total ESV, which initially increased and then declined.
View Article and Find Full Text PDFMar Environ Res
December 2024
Hydro-environmental Research Centre, School of Engineering, Cardiff University, CF10 3AT, Cardiff, UK.
Coastal salt-marsh wetlands have important ecological value, and play an important role in coastal blue carbon sink. However, under the influence of various external and natural factors, coastal wetland ecosystems worldwide have severely degraded, leading to biodiversity loss and ecological damage. Based on satellite remote sensing data and deep learning methods, it is an effective means to quickly monitor the spatial distribution of coastal wetlands, which is very important for the protection and restoration of coastal wetlands.
View Article and Find Full Text PDFJ Hazard Mater
December 2024
Jiaozhou Bay National Marine Ecosystem Research Station, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; Laboratory for Marine Ecology and Environmental Science, Qingdao Marine Science and Technology Center, Qingdao 266237, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address:
Microplastic pollution has become an increasing concern. Vertical transport of microplastics is one of the major research questions concerning the distribution and fate of microplastics in the marine environment, and biologically mediated vertical transport is particularly significant. However, studies on the effects of different types of benthic organisms on the vertical distribution of microplastics in sediments are still scarce.
View Article and Find Full Text PDFJ Hazard Mater
November 2024
Institute of Oceanographic Instrumentation, Qilu University of Technology (Shandong Academy of Sciences), Qingdao 266061, China. Electronic address:
Monitoring heavy metal concentrations in marine sediments is important for assessing marine environmental quality, protecting ecological health, and preventing human health risks. Visible-near infrared spectroscopy technology can overcome the shortcomings of traditional methods. Taking marine sediments from Jiaozhou Bay, Qingdao as an example, this paper collected visible-near infrared spectroscopy of the marine sediments and innovatively proposed a two-scale LSTM with attention mechanism method to predict heavy metal concentrations in marine sediments.
View Article and Find Full Text PDFJ Hazard Mater
November 2024
Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Health and Environment, Jianghan University, Wuhan 430056, China. Electronic address:
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