TY  - JOUR
A1  - Tang, Kam W.
A1  - Flury, Sabine
A1  - Grossart, Hans-Peter
A1  - McGinnis, Daniel F.
T1  - The Chaoborus pump: Migrating phantom midge larvae sustain hypolimnetic oxygen deficiency and nutrient internal loading in lakes
JF  - Water research
N2  - Hypolimnetic oxygen demand in lakes is often assumed to be driven mainly by sediment microbial processes, while the role of Chaoborus larvae, which are prevalent in eutrophic lakes with hypoxic to anoxic bottoms, has been overlooked. We experimentally measured the respiration rates of C flavicans at different temperatures yielding a Q(10) of 1.44-1.71 and a respiratory quotient of 0.84-0.98. Applying the experimental data in a system analytical approach, we showed that migrating Chaoborus larvae can significantly add to the water column and sediment oxygen demand, and contribute to the observed linear relationship between water column respiration and depth. The estimated phosphorus excretion by Chaoborus in sediment is comparable in magnitude to the required phosphorus loading for eutrophication. Migrating Chaoborus larvae thereby essentially trap nutrients between the water column and the sediment, and this continuous internal loading of nutrients would delay lake remediation even when external inputs are stopped. (C) 2017 Elsevier Ltd. All rights reserved.
KW  - Chaoborus
KW  - Eutrophication
KW  - Oxygen
KW  - Nutrient
KW  - Remediation
Y1  - 2017
U6  - https://doi.org/10.1016/j.watres.2017.05.058
SN  - 0043-1354
VL  - 122
SP  - 36
EP  - 41
PB  - Elsevier
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Iturri, Laura Antonela
A1  - Funk, Roger
A1  - Sommer, Michael
A1  - Buschiazzo, Daniel
T1  - Transport preferences of P forms in wind-blown sediments of two susceptible soils
JF  - Aeolian research : an international journal on wind erosion research / International Society of Aeolian Research
N2  - Wind erosion of agricultural soils affects their stock of essential elements for plants, like phosphorus (P). It is known that the composition of the eroded sediments varies with height, according to the size and density of the transported substances. Aim of this study was to analyze the concentration and enrichment ratios of P forms in sediments transported by the wind. A wind-tunnel study was performed on a sandy-and a sandy loam soil in order to measure P forms concentrations in the saltating sediments. P concentrations were also measured in the particulate matter (PM) of each soil, gained with the Easy Dust Generator. In both soils, inorganic-(Pi) and organic P (Po) were preferentially transported in PM, with enrichment ratios of 1.8 and 5.5, respectively. Nevertheless, a Pi/Po of 0.9 indicated that the accumulation of the minor Po in PM was more pronounced than Pi. This agrees with P-rich light and easily erodible organic compounds, almost exclusively accumulated in PM, and in relatively heavy and less erodible minerals, like apatites, in lower height sediments. Labile P (Pl) was preferentially transported in saltating sediments of both soils. This was attributed to the selective Bray & Kurtz I's extraction of the abundant inorganic P forms of these sediments. Total P (Pt) copied the transport trends of Pi, the major form. According to the transporting trends, Pi and Po would be re-sedimented at longer distances from the source than Pl. Outcomes become useful for modeling the influence of wind erosion on P cycling.
KW  - Nutrient
KW  - Soil fertility
KW  - Wind erosion
KW  - Semiarid
KW  - Wind tunnel
Y1  - 2022
U6  - https://doi.org/10.1016/j.aeolia.2022.100776
SN  - 1875-9637
VL  - 55
PB  - Elsevier
CY  - Amsterdam [u.a.]
ER  -