Mr Volodymyr Ivanov, National University of Food Technologies, Ukraine. Global Symposium on Soil Erosion (GSER19), 15 - 17 May 2019 at FAO HQ.

1. Novel biotechnological methods of soil
erosion control to achieve sustainable
development goals: economic growth, food
self-sufficiency, and clean water
Volodymyr Ivanov, Viktor Stabnikov
National University of Food Technologies, 68 Volodymyrska Str., Kyiv 01601, Ukraine,
cvivanov@nuft.edu.ua ; cvivanov111@gmail.com
INTRODUCTION
Soil erosion can be controlled using
conventional agricultural, mechanical and
chemical techniques. However, all known
methods of chemical stabilization of soil to
control soil erosion either negatively affect
plants or are relatively expensive and
environmentally harmful. Meanwhile,
microorganisms stabilize soil due to
aggregation of soil particles and formation
of soil crust. Therefore, the feasible
approach to stabilize agricultural soil could
be microbially-induced aggregation of soil
particles and formation of soil crust.
The novel biotechnological methods are
based on the microbially-mediated
aggregation of soil particles. Bioaggregating
composition is a mixture of at least three
components: 1) a major inorganic
component producing binding matter, 2) a
component that ensures conditions for the
precipitation of a binder; and 3) either
enzyme or live microbial cells which
catalyze biochemical reactions of a binder
formation.
MAIN RESULTS
Fine sand was spraying by aggregating
solution mixed with bacterial suspension.
The results of these biotechnologies are
diminishing of water- and wind-caused
movement of the fine soil particles, humus,
and plant nutrients, as well as control of
water flows on soil surface. Experimental
data showed that at the dosage of
precipitated calcium 64 kg ha-1 with the
evaluated cost of about US$150 per ha and
linear velocity of water flow 0.17 cm s-1 the
erosion rate of fine sand was decreased
from 66 to 20 kg m-2d-1, the maximum size
of 90% of the soil particles was increased
from 40 to 80 µm, and the releases of the
model soil pollutants such as
phenanthrene, lead , and cells of Bacillus
megaterium were diminished by 70, 70,
and 90%, respectively.
The most prospective processes for the
biotechnological formation of soil crust are:
1) crystallization of calcium (and
magnesium) carbonate due to aerobic
microbial oxidation of calcium (and
magnesium) formate/acetate (Fig.1a);
2) crystallization of calcium carbonate due to
decay of calcium bicarbonate;
3) enhanced formation of cyanobacterial soil
crust;
4) oxidation of ferrous ions produced from
iron ore powder (Fig.1b).
Depending on the quantity of sprayed
bioaggregating solution the different levels of
soil particles biobinding can be achieved
(Figs.2 and 3).
The raw materials for soil-aggregating
solution could be limestone, dolomite,
hematite iron ore, or cement powder, which
are dissolved in acetic, formic, or carbonic
(carbon dioxide dissolved in water) acids.
Soil-aggregating solution could be produced
industrially or by the farmer using acidogenic
fermentation of agricultural wastes with
limestone, dolomite, hematite iron ore, or
cement powder. Bacterial suspension in cases
when it will be needed should be mixed with
the soil-aggregating solution during the soil
treatment. Such biotechnology as soil
aggregation due to aerobic microbial
oxidation of calcium formate/acetate is
recommended for pilot-scale testing of the
biotechnological control of soil erosion.
REFERENCES
Ivanov V., Stabnikov V. (2017) Construction
Biotechnology: Biogeochemistry,
Microbiology and Biotechnology of
Construction Materials and Processes.
Springer, 400 p.
Ivanov V., Stabnikov V., Kawasaki S. (2019)
Ecofriendly calcium phosphate and calcium
bicarbonate biogrouts. Journal of Cleaner
Production, 218: 328-334.
Similar results were obtained for the wind
erosion of soil, when the dosage of precipitated
calcium about 156 kg Ca ha-1 suppressed the
release of the fine sand dust by 99.8 %, increased
the maximum size of 90% of the sand dust
particles from 29 µm to 181 µm, and diminished
the releases of the model soil pollutants such as
phenanthrene, lead, and cells of Bacillus
megaterium by 92.7, 94.4, and 99.8%,
respectively.
(a) (b)
Fig.1. Sand bioaggregated by calcium
Fig.2. Formation of soil crust by
microbially-carbonate (a) or ironhydroxide
(b) mediated products
Fig.3. Strong and weak binding of sand
grains by microbially-mediated products
CONCLUSIONS AND
RECOMMENDATIONS
Bioaggregation treatment of the soil surface could
be useful method to prevent soil erosion and the
release of soil-associated chemical and
bacteriological pollutants in water and air.
Depending on the availability and cost of the raw
materials, different kinds of soil aggregating
biocompositions can be used.