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Sarah Conrad
Sarah Conrad

Sarah Conrad

Associate Senior Lecturer
Luleå University of Technology
Applied Geochemistry
Geosciences and Environmental Engineering
Department of Civil, Environmental and Natural Resources Engineering
sarah.conrad@ltu.se
+46 (0)920 493478
T2322 Luleå

My interest in applied geochemistry is focused on the link between terrestrial, limnic, and marine systems. My research includes the export of metals from the terrestrial environment into surface waters, their fate along the watercourse, and subsequently, their impact on the receiving system. Multi-element geochemical studies of element concentrations, mobility, and isotope composition within the different environments reveal their source and behavior. I would like to add to a clear understanding of the geochemical processes taking place in the terrestrial and hydrological cycle. I believe it is essential to understand chemical weathering of minerals as it is the fundament that replenishes the soil mineral nutrient reserve and ultimately nourishes terrestrial and aquatic ecosystems. Ongoing changes in climate and land use are expected to impact the mineral nutrient cycling and the mineral nutrient export to rivers. I think an analytical approach combining isotope geochemistry with pedology, geology, and biogeochemistry will improve the knowledge about the complex interacting of (a)biotic processes involved in mineral weathering.

My scientific background includes the detailed knowledge of stable isotope systems in our environment. As Ph.D. student (Luleå University of Technology, 2019) I focused on the characterization of Fe isotope ratios from the source (e.g., soils), along the river course, through the estuaries, and into the adjacent sea. Iron is a key component for understanding water quality and biogeochemical processes. I documented and interpreted the variation of Fe phases in response to seasonal differences in hydrology. As Research Associate (Earth Observatory of Singapore 2019-2020) I analyzed and interpreted d18O, d2H, and d34S stable isotope variations in evaporation and precipitation samples to understand the driving mechanisms of spatial and temporal variations in tropical regions. Such knowledge will help to interpret past climate archives and understand regional to global climate dynamics, which can be used to predict future scenarios, particularly water resource sustainability.

Publications

Article in journal

Distribution of Fe isotopes in particles and colloids in the salinity gradient along the Lena River plume, Laptev Sea (2019)

Conrad. S, Ingri. J, Gelting. J, Nordblad. F, Engström. E, Rodushkin. I, et al.
Biogeosciences, Vol. 16, nr. 6, s. 1305-1319
Doctoral thesis, comprehensive summary

Iron isotopes in aquatic systems (2019)

Conrad. S
Article in journal

Seasonal Variations of Redox State in Hemiboreal Soils Indicated by Changes of δ56Fe, Sulfate, and Nitrate in Headwater Streams (2019)

Conrad. S, Löfgren. S, Bauer. S, Ingri. J
ACS Earth and Space Chemistry, Vol. 3, nr. 12, s. 2816-2823
Article in journal

Spring flood induced shifts in Fe speciation and fate at increased salinity (2019)

Herzog. S, Conrad. S, Ingri. J, Persson. P, Kritzberg. E
Applied Geochemistry, Vol. 109
Article in journal

The stability of Fe isotope signatures during low salinity mixing in subarctic estuaries (2019)

Conrad. S, Wuttig. K, Jansen. N, Rodushkin. I, Ingri. J
Aquatic geochemistry, Vol. 25, nr. 5-6, s. 195-218