Wyniki wyszukiwania - BazTech

1

Seasonal characteristics of nutrient and nutrient structure in the Yangtze River estuary

Li Lei, Xv Guodong, Zheng Yingjie, Jiang Mei

Archives of Environmental Protection

|

2023

|

Vol. 49, no 3

115--122

EN

This data article aimed to evaluate the influencing mechanisms of the nutrients and the level of eutrophication in the Yangtze River estuary. The seasonal characteristics of nutrients (dissolved inorganic nitrogen (DIN), SiO3-2–Si, and PO43-P) in the seawater of the Yangtze River estuary were analyzed by conducting surveys in spring and summer of 2019. The findings revealed that the concentrations of all nutrient at the surface and bottom layers were lower in spring compared to summer. NO3–N was typically the major form of DIN. Runoff was identified as the primary source of DIN and SiO32−–Si, while PO43−–P originated from a various sources. The SiO32−–Si, while PO43−–P values in the surface and bottom layers during the spring and summer were higher than the Redfield values, indicating an imbalanced nutrient distribution. Furthermore, discrepancies were observed in the distributions of DIN/PO43−–P, SiO32−–Si/DIN, and SiO32−–Si/PO43−–P in the Yangtze River estuary. Through an examination of the ratio of DIN/PO43−–P absorbed by phytoplankton, PO43−–P was identified as a potential limiting factor for nutrition in the sea area of the Yangtze River estuary during spring and summer. The Eutrophication Index (E) values for both spring and summer were found to be higher than the eutrophication threshold, indicating severe eutrophication in the studied sea area.

2

On the Temporal Variability of Air Pollutants’ Emissions – Case Study of Residential PM10 Emission in Silesian Metropolis

Zasina Damian, Zawadzki Jarosław

New Trends in Production Engineering

|

2020

|

Vol. 3, Iss. 1

21--29

EN

The paper summarizes previous studies associated with carrying out of the air pollutant emission inventories. There are presented three approaches for obtaining monthly distribution of PM10 air emission: using expert’s judgement, modelling of the heating demand, and temporal disaggregation using the heating degree days (HDD). However some differences due to not considering hot water demand, it can be effectively used for obtaining temporal, and spatiotemporal distributions of air pollutants’ air emissions necessary for air quality modelling.

3

Recrutation and settlement of young flounder (Platichthys flesus) in the western part of the Gulf of Gdańsk (Baltic)

Sapota M.R., Kamińska U.

Oceanological Studies

|

1998

|

Vol. 27, No. 3

31-42

EN

On a basis of whole year monthly sampling, the abundance of the flounder in inshore shallow waters of the western part of the Gulf of Gdansk was established. Flounders were observed almost all year. Only in winter, when sea ice forming proc-esses occurred, they disappeared from the investigated zone. The highest abundance of the flounder was noticed in Hel vicinity. No flounders were observed in inshore waters of the Puck Lagoon. Young flounders occurred in the highest number in July (average for all investigated area amounted to 2.81 individuals 100/ m^2). In that month, this-year-born flounders settle in the inshore shallow water zone. The highest biomass was noticed in August (average 4.98 g/100 m^2) when older bigger flounders more frequently inhabited inshore zone. Body proportions of young flounders during their growth in inshore shallow waters of the Gulf of Gdansk are stable. All measured distances were increasing linearly with the growth of flounder length.