A case‐study on history and rates of gully erosion in Northeast China

Abstract

Mollisols are of major importance for food security worldwide but are increasingly degraded by soil erosion. Mollisols in Northeast China have been converted into agricultural use only since the 19th century, but gullies are widely distributed. Gully erosion history, rates, and causes in this region remained unclear. We chose a study area with landforms and land-use history typical for the central Mollisol region of Northeast China to estimate the initiation years and rates of gully erosion from 1968 to 2018 using aerial and satellite imageries. The outlet fan deposits of a large gully system were dated by Cesium-137 ( 137 Cs) and artifacts. Local farmers were interviewed to verify the results. Gully volumes were measured by a structure-from-motion technique using photos taken from an unmanned aerial vehicle. Our results showed that gully systems had already appeared on the steep slopes and along unpaved roads in 1968. They had become larger and more complex in 2018 by the upslope retreat of the main gullies and side gully formation. Gully incision started in the 1950s and 1960s when the original grassland and forest were completely converted into arable land. From 1968 to 2018, the gully density increased from 1.2 to 2.3 km km À2 and the gully heads retreated at speeds from 1.5 to 2.5 m yr À1 . The soil loss from gully erosion ranged from 25.7 to 44.7 Mg yr À1 ha À1 . These data demonstrate the severity of gully erosion in the Mollisol region of Northeast China and underline the importance of appropriate countermeasures.

Recent gully erosion intensity in an agricultural landscape underlain by fluvioglacial sediments (NE Czechia)

“…The same effect of abandoned field roads on gully development was found in Poland (Gardziel et al, 1998;Gardziel & Rodzik, 2001;Schmitt et al, 2006;Dotterweich et al, 2012;Rodzik et al, 2015), Slovakia (Stankoviansky, 2003), or China (Zhang et al, 2019;Wen et al, 2021). In eastern Poland, Rodzik et al (2015) and Szwarczewski et al ( 2020) also described gully incision as a combined effect involving the presence of an abandoned field road and fine sandy deposits, as is the case in the Fb gully.…”

Gully erosion on alluvial fans can be mitigated by altering the hydrological connectivity between an alluvial fan and the contributing catchment: a study in the Lhasa River basin

“…It is generally found that human activities accelerated gully erosion mainly by destroying vegetation and changing land use (Kang, Wang, et al, 2021; Poesen, 2018; Shellberg, 2021; Wen et al, 2021). But in this research, human activities reduced the gully quantitative characteristics of AF to a certain extent (Figure 4).…”

“…Gully development includes headcut retreat, sidewall collapse, and bed downcutting (Harvey, 1992). Gully erosion is affected by many influencing factors, including soil, lithology, climate, topography, vegetation, and human activities (Kang, Wang, et al, 2021; Poesen, 2018; Shellberg, 2021; Wen et al, 2021). As the materials of gully erosion, soil and lithology determine the erodibility (Poesen, 2018; Zhu et al, 2020).…”

Root Distribution and Soil Properties of Gully Heads and Their Effects on Headcut Migration in the Mollisols Region of Northeast China

“…The Mollisols area of northeast China (NEC), as one of the four largest mollisols regions globally, and is the base of grain production in China [34], but it is being restricted by gully erosion [35]. At present, there are 296,000 gullies in the Mollisols area of NEC [36,37], of which 89% of the gullies are still in the developing stage, and gully erosion has damaged up to 2.2 × 10 5 ha of land that accounts 0.4% of the total area of NEC, indicating that the gully erosion rate is high and that its risk extended gradually [38].…”