What is the affinity of polutants to particulate terrestrial organic matter carried by rivers??10 answersThe affinity of pollutants to particulate terrestrial organic matter (POM) carried by rivers is a complex interaction influenced by various factors, including the nature of the organic matter, the type of pollutants, and the hydrodynamic conditions of the river system. Terrestrial organic matter, as it enters river systems, can be a significant carrier of pollutants, including organic contaminants, due to its interaction with both the water column and riverbed sediments.
Research indicates that terrestrial organic matter, especially in urban watersheds, can carry a mixture of autochthonous, terrestrial, and anthropogenic sources of organic matter, including pollutants from wastewater effluent. The molecular properties of particulate organic matter, such as its physical features and macromolecular composition, play a crucial role in its interaction with pollutants. Hydrodynamic sorting processes in rivers can modify the fluxes of particulate organic carbon, affecting the transport and deposition of pollutants bound to POM. The stable isotopes and C/N ratio analysis of POM in marine sediments further reveal the terrestrial origin of organic matter and its potential to carry pollutants to the marine environment.
Storm events have been shown to mobilize particles and organic contaminants, indicating the significant role of POM in transporting pollutants during such events. The fine particles of POM, which are a major component of the particulate organic matter standing stock in streams, have been identified as key players in the transport and retention of pollutants. In specific river basins, the level of POM and its pollutant load can be significantly influenced by the hydrological environment, including water use for irrigation, which affects the concentration of organic matter and associated pollutants.
Furthermore, the transport of particulate organic matter and its relation to stream power has been studied to understand the dynamics of POM concentration and pollutant transport. In small mountainous rivers, changes in the sources and fluxes of POC during rain events highlight the sensitivity of POM to hydrological conditions and its role in exporting terrestrial pollutants. Collectively, these studies underscore the intricate relationship between particulate terrestrial organic matter and pollutants, emphasizing the importance of hydrological, biological, and chemical processes in determining the affinity and transport of pollutants by rivers.
Does the oxygenated seawater mobilize dissolved organic matter from the sediment to the water in estuary?4 answersOxygenated seawater can indeed mobilize dissolved organic matter (DOM) from sediment to the water in estuaries. Studies have shown that in estuarine environments like the Pearl River Estuary, the presence of oxygenated seawater leads to the degradation and preservation of DOM in sediment cores, influencing the spatial distribution and sources of DOM. Additionally, in areas like the Lower St. Lawrence Estuary, the presence of oxygen in seawater can affect the degradation pathways of organic matter, potentially allowing for the accumulation of labile organic matter due to reduced degradation rates under hypoxic conditions. Furthermore, in the Gulf of Gdansk, sediment-derived DOM with distinct fluorescence signatures can be mobilized into the water column, contributing to bottom water oxygen consumption. These findings collectively suggest that oxygenated seawater plays a crucial role in mobilizing and influencing the fate of dissolved organic matter in estuarine sediments.
Source of POPs and emerging pollutants in marine environment in adriatic are rivers?5 answersThe sources of Persistent Organic Pollutants (POPs) and emerging pollutants in the marine environment of the Adriatic Sea include rivers. Rivers like Vjosa, Semani, Shkumbini, Erzeni, Mati, and Buna in Albania transport agricultural, industrial, and urban waste into the Adriatic Sea, leading to the presence of organochlorine pesticides, polychlorinated biphenyls (PCBs), and polyaromatic hydrocarbons (PAHs) in the water. Additionally, the Northwestern Adriatic Sea is affected by plastic pollution, with microplastics originating from sources like the lagoon of Venice and the Po River, highlighting the contribution of rivers to marine pollution in the region. These pollutants pose risks to marine ecosystems and human health, emphasizing the importance of continuous monitoring to safeguard the environment and economic activities like fishing and tourism in the Adriatic Sea.
How large source of underwater noise in marine environment in adriatic are rivers?5 answersRivers are not highlighted as a significant source of underwater noise in the marine environment in the Adriatic region. Instead, human activities such as marine traffic, nautical tourism, fishing, and seismic surveys are identified as major contributors to underwater noise pollution. Recreational vessels during the tourist season are specifically noted as dominant anthropogenic sources of underwater noise in the Adriatic coastal habitat. Additionally, seismic surveys conducted for natural gas exploration off Montenegro in the Adriatic Sea have been recognized as important sources of low-frequency ocean ambient noise, potentially impacting cetaceans in the region. Therefore, while rivers may introduce some noise, the primary sources of underwater noise in the Adriatic marine environment stem from various human activities rather than rivers.
Does the presence of tides influence the production of organic molecules in marine environments?5 answersThe presence of tides does influence the production of organic molecules in marine environments. Tidal forcing increases biological productivity on the northwest European shelf (NWES) and around 16% of annual mean primary production on the shelf is related to tidal forcing. Tidal impacts on primary production are particularly invigorated in tidal frontal regions due to vertical mixing of nutrients by the barotropic tide. Tides also play a significant role in the dispersion patterns of sedimentary organic matter (OM) in tidal estuaries, with fine particles such as silt and clay being the major carriers of OM signals. In highly dynamic mangrove intertidal systems, tidal hydrology drives groundwater dissolved organic matter (DOM) properties, with tidally driven surface water-groundwater interactions controlling the variability in DOM properties and its contribution to carbon budgets and sequestration. Additionally, green tides caused by macroalgal blooms have a profound effect on shaping coastal dissolved organic carbon (DOC), with macroalgae being an important source of recalcitrant DOC that has the potential for long-term carbon sequestration.
What has the most organic matter?7 answers