Results 41 to 50 of about 19,968 (263)

Stabilizing Inference in Dirichlet Regression via Ridge‐Penalized Model

Statistical Analysis and Data Mining: An ASA Data Science Journal, Volume 19, Issue 1, February 2026.
ABSTRACT We propose a penalized Dirichlet regression framework for modeling compositional data, using a softmax link to ensure that the mean vector lies on the simplex and to avoid log‐ratio transformations or zero replacement. The model is formulated in a GLM‐like setting and incorporates an ℓ2$$ {\mathrm{\ell}}_2 $$ (ridge) penalty on the regression ...
Andrea Nigri
wiley   +1 more source

Transmission of Heavy Metals in River Water and Self-Purification Capacity of Ile River

Applied Sciences
The continuing anthropogenic pollution of the Ile River occurs both by transboundary runoff and as a result of discharges of industrial, agricultural, and domestic wastewater on the territory of Kazakhstan.
Ainur Mussakulkyzy, Christian Opp, Nariman Amirgaliev, Azamat Madibekov, Laura Ismukhanova, Askhat Zhadi   +5 more
doaj   +1 more source

Abundant production of dimethylsulfoniopropionate as a cryoprotectant by freshwater phytoplanktonic dinoflagellates in ice-covered Lake Baikal

Communications Biology, 2023
Phytoplanktonic dinoflagellates form colonies between vertical ice crystals during the ice-melting season in Lake Baikal, but how the plankton survive the freezing conditions is not known.
Kei Toda, Vladimir Obolkin, Shin-Ichi Ohira, Kentaro Saeki   +3 more
doaj   +1 more source

Can Mg isotopes be used to trace cyanobacteria-mediated magnesium carbonate precipitation in alkaline lakes? [PDF]

, 2011
The fractionation of Mg isotopes was determined during the cyanobacterial mediated precipitation of hydrous magnesium carbonate precipitation in both natural environments and in the laboratory.
Balor, S., Bundeleva, Irina, Bénézeth, Pascale, Gérard, E., Mavromatis, Vasileios, Oelkers, Eric H., Pearce, Christopher R., Pokrovsky, Oleg S., Shirokova, Liudmilla S.   +8 more
core   +4 more sources

Carbon Cycle Succession Across a Permafrost Thaw Gradient in Northeastern Alberta as Revealed by δ13C in Dissolved Solids, Gases, and Particulates in Lakes

Journal of Geophysical Research: Biogeosciences, Volume 131, Issue 2, February 2026.
Abstract δ13C in particulate organic carbon (POC), dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), carbon dioxide (CO2(g)) and methane (CH4(g)), together with geochemical modeling, were applied to describe carbon cycle evolution in 40 boreal lakes situated across a permafrost thaw gradient in northeastern Alberta, Canada, where ...
J. J. Gibson, P. Eby, A. Jaggi
wiley   +1 more source

Hydrochemistry of Polluted Surface Water

, 2022
Surface water is one of the most significant sources of natural ecosystems existence, climate regulation, broadly used for economic activity, drinking water supply, recreation, irrigation, etc. Therefore, chemical composition and grade of water pollution are of great importance to evaluate the ecological state of water resources and their usage in ...
Viorica Gladchi, Elena Bunduchi, Vladislav Blonschi, Lidia Romanciuc   +3 more
openaire   +2 more sources

Aquatic Ecosystem Deterioration and Its Potential Drivers in a Floodplain Lake in the Lower Yellow River Area, North China

Ecology and Evolution, Volume 16, Issue 1, January 2026.
This study employed Landsat imagery and Support Vector Machine to extract spring and summer aquatic vegetation distribution in Dongping Lake, combined with field survey data and environmental factors to analyze its succession over the past 40 years. Redundancy Analysis was then used to investigate the factors driving aquatic ecosystem deterioration ...
Yingying Chen, Yanyu Ji, Qinghui Zhang, Yunwei Zhang, Shi‐Yong Yu, Shiyue Chen   +5 more
wiley   +1 more source

Macroelements in the surface microlayer of water of urban ponds

Limnological Review, 2016
Analyses were conducted concerning the accumulation of four metals representing the group of macroelements, i.e. sodium, potassium, calcium and magnesium in two ponds located in the city of Słupsk.
Antonowicz Józef Piotr, Kubiak Jacek, Machula Sylwia   +2 more
doaj   +1 more source

Microbial and Geochemical Evidence of Permafrost Formation at Mamontova Gora and Syrdakh, Central Yakutia

Frontiers in Earth Science, 2021
Biotracers marking the geologic history and permafrost evolution in Central Yakutia, including Yedoma Ice Complex (IC) deposits, were identified in a multiproxy analysis of water chemistry, isotopic signatures, and microbial datasets.
M. Yu. Cherbunina, E. S. Karaevskaya, Yu. K. Vasil’chuk, N. I. Tananaev, D. G. Shmelev, N. A. Budantseva, A. Y. Merkel, A. L. Rakitin, A. V. Mardanov, A. V. Brouchkov, S. A. Bulat, S. A. Bulat   +11 more
doaj   +1 more source

Impacts of land-use and land-cover change on stream hydrochemistry in the Cerrado and Amazon biomes [PDF]

, 2018
Studies on the impacts of land-use and land-cover change on stream hydrochemistry in active deforestation zones of the Amazon agricultural frontier are limited and have often used low-temporal-resolution datasets.
Amorim, Ricardo S. S., Couto, Eduardo G., Gerhard, Gerold, Guzha, Alphonce C., Hughes, Harold J., Jungkunst, Hermann F., Lamparter, Gabriele, Nobrega, Rodolfo L. B.   +7 more
core   +2 more sources