TY  - JOUR
A1  - Tran, C. T.
A1  - Mai, N. T.
A1  - Nguyen, V. T.
A1  - Nguyen, H. X.
A1  - Meharg, A.
A1  - Carey, M.
A1  - Dultz, S.
A1  - Marone, F.
A1  - Cichy, Sarah Bettina
A1  - Nguyen, Minh N.
T1  - Phytolith-associated potassium in fern
BT  - characterization, dissolution properties and implications for slash-and-burn agriculture
JF  - Soil use and Management
N2  - In recent time, phytoliths (silicon deposition between plant cells) have been recognized as an important nutrient source for crops. The work presented here aims at highlighting the potential of phytolith-occluded K pool in ferns. Dicranopteris linearis (D.linearis) is a common fern in the humid subtropical and tropical regions. Burning of the fern D.linearis is, in slash-and-burn regions, a common practice to prepare the soil before planting. We characterised the phytolith-rich ash derived from the fern D.linearis and phytolith-associated potassium (K) (phytK), using X-ray tomographic microscopy in combination with kinetic batch experiments. D.linearis contains up to 3.9g K/kgd.wt, including K subcompartmented in phytoliths. X-ray tomographic microscopy visualized an interembedding structure between organic matter and silica, particularly in leaves. Corelease of K and Si observed in the batch experiments confirmed that the dissolution of ash phytoliths is one of major factors controlling K release. Under heat treatment, a part of the K is made available, while the remainder entrapped into phytoliths (ca. 2.0-3.3%) is unavailable until the phytoliths are dissolved. By enhanced removal of organic phases, or forming more stable silica phases, heat treatment changes dissolution properties of the phytoliths, affecting K release for crops and soils. The maximum releases of soluble K and Si were observed for the phytoliths treated at 500-800 degrees C. For quantitative approaches for the K provision of plants from the soil phytK pool in soils, factors regulating phytolith dissolution rate have to be considered.
KW  - Potassium
KW  - phytolith
KW  - fern
KW  - Dicranopteris linearis
Y1  - 2018
U6  - https://doi.org/10.1111/sum.12409
SN  - 0266-0032
SN  - 1475-2743
VL  - 34
IS  - 1
SP  - 28
EP  - 36
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Frick, Daniel Alexander
A1  - Schüßler, Jan Arne
A1  - Sommer, Michael
A1  - von Blanckenburg, Friedhelm
T1  - Laser Ablation In Situ Silicon Stable Isotope Analysis of Phytoliths
JF  - Geostandards and geoanalytical research
N2  - Silicon is a beneficial element for many plants and is deposited in plant tissue as amorphous bio-opal called phytoliths. The biochemical processes of silicon uptake and precipitation induce isotope fractionation: the mass-dependent shift in the relative abundances of the stable isotopes of silicon. At the bulk scale, delta Si-30 ratios span from -2 to +6 parts per thousand. To further constrain these variations in situ, at the scale of individual phytolith fragments, we used femtosecond laser ablation multi-collector inductively coupled plasma-mass spectrometry (fsLA-MC-ICP-MS). A variety of phytoliths from grasses, trees and ferns were prepared from plant tissue or extracted from soil. Good agreement between phytolith delta Si-30 ratios obtained by bulk solution MC-ICP-MS analysis and in situ isotope ratios from fsLA-MC-ICP-MS validates the method. Bulk solution analyses result in at least twofold better precision for delta Si-30 (2s on reference materials <= 0.11 parts per thousand) over that found for the means of in situ analyses (2s typically <= 0.24 parts per thousand). We find that bushgrass, common reed and horsetail show large internal variations up to 2 parts per thousand in delta Si-30, reflecting the various pathways of silicon from soil to deposition. Femtosecond laser ablation provides a means to identify the underlying processes involved in the formation of phytoliths using silicon isotope ratios.
KW  - In situ silicon isotope ratio analysis
KW  - phytolith
KW  - laser ablation inductively coupled plasma-mass spectrometry
KW  - biogenic silica
Y1  - 2018
U6  - https://doi.org/10.1111/ggr.12243
SN  - 1639-4488
SN  - 1751-908X
VL  - 43
IS  - 1
SP  - 77
EP  - 91
PB  - Wiley
CY  - Hoboken
ER  -