Search results for "sapropel"

Sapropelis un tā izmantošanas iespējas

2014

Sapropelis ir ar organiskajām vielām bagāti nogulumi, kas nogulsnējas ūdenstilpēs. Sapropeļa izplatība un plasas izmantosanas iespējas padara to par nozīmīgu dabas resursu, ko var izmantot lauksaimniecībā, dārzkopībā, mežsaimniecībā, lopkopībā, ķīmijas un celtniecības industrijā, balneoloģijā un kosmetoloģijā. Kopējie sapropeļa resursi Latvijā sastāda aptuveni 2 miljardus m3. Sī raksta mērķis ir aplūkot sapropeļa klasifikāciju, veidosanās apstākļus un izmantosanas jomas.

Surface hydrographic changes at the western flank of the sicily channel associated with the last sapropel

2021

Abstract In the eastern Mediterranean Sea, the early Holocene was characterized by major climatic and oceanographic changes that led to the formation of the last sapropel (S1) between 10.8 and 6.1 kyr cal. BP. These hydrographic changes might have altered the water exchange between the eastern and western Mediterranean sub-basins through the Strait of Sicily, but the existing evidences are inconclusive. In the present study we show new evidence from sediment core NDT-6-2016 located at the western flank of the Sicily channel, a key location to monitor the surface/intermediate water exchange between the two Mediterranean sub-basins. We perform paleo-hydrographic reconstructions based on plank…

Sapropeļa izmantošana personīgās higiēnas līdzekļos: sapropeļa cieto ziepju īpašības un izmantošanas dzīves cikla novērtējums

2015

Bakalaura darba “Sapropeļa izmantošana personīgas higiēnas līdzekļos: sapropeļa cieto ziepju īpašības un izmantošanas dzīves cikla novērtējums” ietvaros tika noteikti triju tirgū pieejamo un četru paštaisīto ezeru nogulumu cieto ziepju kvalitātes rādītāji un īpašības, paštaisītām ziepēm tika modelēts izmantošanas dzīves cikls. Paštaisītās sapropeļa ziepes tika pagatavotas, izmantojot sapropeli kā pildījumu. Darba teorētiskajā daļā tika veikta zinātniskās literatūras analīze par cieto ziepju pagatavošanas metodēm, piedevu īpašībām un to sastāvu, produkta izmantošanas dzīves ciklu, kā arī par sapropeļa izmantošanu kosmetoloģijā un balneoloģijā. Bakalaura darba ietvaros pēc autores izstrādātās…

Dynamics at the Strait of Sicily and Mediterranean Sapropels

2012

Benthic foraminiferal assemblage turnover during intensification of the Northern Hemisphere glaciation in the Piacenzian Punta Piccola section (South…

2012

Abstract We present the results of a high-resolution analysis of the benthic foraminiferal assemblages at the Punta Piccola section (Stratotype for the Piacenzian Stage), which spans the gradual climate transition of the intensification of the Northern Hemisphere glaciation (3.6–2.6 Ma). This study highlighted a major benthic foraminiferal fauna turnover, which started at about 3.05 Ma with LO of Cibicidoides italicus , registered the gradual decline of Stilostomella spp. and culminated at about 2.7–2.75 Ma, when the dominant Siphonina reticulata was replaced by Cibicidoides pachyderma , costate Bulimine, spinose Bulimine, spinose Uvigerine and the Bolivina dilatata group. Four compositiona…

Calcareous Nannofossil and Planktonic Foraminifera Biostratigraphy of selected Piacenzian-Gelasian Laminites from Southern Italy

2011

Here we present the biostratigraphic and chronostratigraphic framework of a number of selected diatomaceous laminated intervals from the Crotone Basin (Calabria, Southern Italy). These layers, which we consider correlative to the Eastern Mediterranean Sapropel Layers, range in age from the early Piacenzian to the Gelasian, and show surprising thicknesses, suggesting that they were probably laid down in a landlocked, overfed basin. Specifically, a thick laminite from the surroundings of Cropani (Catanzaro) can be ascribed to nannofossil biozone MNN 16a and planktonic foraminifera biozone MPL 4b (lower Piacenzian) according to the Mediterranean calcareous plankton biostratigraphic zonations. …

The Postglacial Isotopic Record of Intermediate Water Connects Mediterranean Sapropels and Organic‐Rich Layers

2020

Carbon‐rich layers exist at both sides of the Mediterranean Sea sedimentary record and are called sapropels and organic rich layers (ORLs), respectively, in the eastern and western basins. They have different levels of organic carbon accumulation and seafloor oxygen deprivation. The most recent sapropel and ORL depositions have a different timing, approximately 10.8–6.1 and 14.5–9.0 ka, respectively. Here we investigate oxygen isotopic records of three foraminifera species that occupy different habitats within the Sicily Channel water column since ~12.0 ka, thus in the sill between the eastern and western Mediterranean basins. These data are ice volume corrected, to get information on water…

Surface and deep water conditions in the Sicily channel (central Mediterranean) at the time of sapropel S5 deposition

2011

New centennial-scale data of benthic foraminifera assemblages and of stable isotopes of foraminifera shells from the Sicily Channel, representative of surface and bottom waters, over the interval between about 140 and 110 kyr BP, are presented. During this period anoxia developed on the eastern Mediterranean basin and sapropel S5 deposited. Although anoxic sediments have not been deposited in the Sicily Channel, this area is strategic to study the character of intermediate waters, whose chemical-physical properties strongly precondition the eastern Mediterranean deep water formation. So far, no data from these water masses have been obtained, apart from the isotopic composition of shells of…

African monsoon variability during the previous interglacial maximum.

2002

Little is known about centennial- to millennial-scale climate variability during interglacial times, other than the Holocene. We here present high-resolution evidence from anoxic (unbioturbated) sediments in the eastern Mediterranean Sea that demonstrates a sustained V800-yr climate disturbance in the monsoonal latitudes during the Eemian interglacial maximum (V125 ka BP). Results imply that before and after this event, the Intertropical Convergence Zone (ITCZ) penetrated sufficiently beyond the central Saharan watershed (V21n) during the summer monsoon to fuel flooding into the Mediterranean along the wider North African margin, through fossil river/wadi systems that to date have been cons…

Sapropeļa kūdras, sapropeļa kokskaidu siltumizolācijas plāksnes un to īpašības

2014

Siltumizolācijas materiāli, kuros par pildvielu tiktu izmantoti vietējie biomasas produkti, bet par saistvielu kalpotu dabiskas izcelsmes saistvielas, piemēram, sapropelis, uzskatāmi par inovatīviem un to pielietošana sekmētu ekoloģiskās būvniecības nozares attīstību. Šādu risinājumu izstrāde ir aktuāla, jo Latvijā ir ievērojami sapropeļa resursi, kuru izmantošanu kavē to nepietiekama izpēte un ekoloģiskās būvniecības nozares intensīva attīstība. Pētījuma mērķis ir iegūt sapropeļa-koksnes, kūdras-koksnes siltumizolācijas plāksnes, noteikt optimālās plātnes sastāva attiecības un raksturot iegūto plātņu īpašības. Veikto pētījumu rezultātā tika noteiktas siltumizolācijas materiālu paraugu mehā…