Grazing effects on total carbon and nitrogen content of wind-eroded
soils in desert steppe
Abstract
A high stocking rate can intensify wind erosion in grasslands, and
strong wind can carry away soil surface particles and their nutrients,
which leads to soil barrenness. In this research, the dust flux, total
carbon (TC) and total nitrogen (TN) contents and fluxes of aeolian
sediment were computed in the non-growing season (mid-October to
mid-April of the following year) and growing season (mid-April to
mid-October) from 2018 to 2020 at a long-term grazing gradient
experiment platform and wind-erosion monitoring experiment in a desert
steppe in Inner Mongolia, China. The results were as follows, 1) with
the increasing of stocking rate, the fluxes of aeolian sediment at 10 cm
(H10), 30 cm (H30), and 100 cm (H100) were greatly increased (
P<0.05). Aeolian sediment fluxes followed the order
control (CK) < light stocking rate (LG) < moderate
stocking rate (MG) < heavy stocking rate (HG). 2) TC and TN
contents of aeolian sediment reflected stocking rates and followed the
order CK>LG>MG>HG, and also
reflected aeolian sediment collection height, as
H10P>0.05). TC and TN contents in HG at different heights
reduced by 31.1% and 25.9% on average in comparison to the CK in the
non-growing season, and by 30.1% and 25.0% in the growing season. TC
loss was higher than TN loss. Overall, as stocking rate increased, wind
erosion increased, leading to the loss of soil nutrients and significant
loss of the carbon pool in this desert steppe.