Anthropogenic dust emissions due to livestock trampling in a Mongolian temperate grassland
Mongolian grasslands are a natural dust source region and they contribute to anthropogenic dust due to the long tradition of raising livestock there. Past decades of abrupt changes in a nomadic society necessitate a study on the effects of livestock trampling on dust emissions, so that research...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2017-09-01
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| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://www.atmos-chem-phys.net/17/11389/2017/acp-17-11389-2017.pdf |
| Summary: | Mongolian grasslands are a natural dust source region and they
contribute to anthropogenic dust due to the long tradition of raising
livestock there. Past decades of abrupt changes in a nomadic society
necessitate a study on the effects of livestock trampling on dust
emissions, so that research studies may help maintain a sustainable
ecosystem and well-conditioned atmospheric environment. In this study,
we conducted a mini wind tunnel experiment (using a
PI-SWERL<sup>®</sup> device) to measure dust emissions fluxes
from trampling (at three disturbance levels of livestock density,
<i>N</i>) and zero trampling (natural as the background level) at
test areas in a Mongolian temperate grassland. Moreover, we scaled
anthropogenic dust emissions to natural dust
emissions as a relative
consequence of livestock trampling. We found a substantial increase
in dust emissions due to livestock trampling. This effect
of trampling on dust emissions was persistent throughout all wind
friction velocities, <i>u</i><sub>*</sub> (varying from 0.44 to
0.82 m s<sup>−1</sup>). Significantly higher dust loading
occurs after a certain disturbance level has been reached by the
livestock trampling. Our results suggest that both friction velocity
(<i>u</i><sub>*</sub>) and disturbance level of livestock density (<i>N</i>) have an enormous
combinational effect on dust emissions from the trampling test surface.
This means that the effect of livestock trampling on dust emissions can be
seen or revealed when wind is strong. Our results also emphasize that
better management for livestock allocation coupled with strategies
to prevent anthropogenic dust loads are needed. However, there are many
uncertainties and assumptions to be improved on in this study. |
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| ISSN: | 1680-7316 1680-7324 |