The influence of rainfall and land use patterns on soil erosion in multi-scale watersheds: A case study in the hilly and gully area on the Loess Plateau, China

Controlling soil erosion is beneficial to the conservation of soil resources and ecological restoration. Understanding the spatial distribution characteristics of soil erosion helps find the key areas for soil control projects and optimal scale for investing in a soil and water conservation project at the lowest cost. This study aims to answer the question of how the spatial distribution of soil erosion in Hubei Province changed between 2000 and 2020. Moreover, how do the effects of natural factors and human activities on soil erosion vary over the years? What are the differences in landscape pattern characteristics and the spatial cluster of soil erosion at multiple administrative scales? We simulated the spatial distribution of soil erosion in Hubei province from 2000 to 2020 by the Chinese Soil Loss Equation model at three administrative scales. We investigated the relationship between soil erosion and driving factors by Geodector. We explored the landscape pattern and hotspots of land at different levels of soil erosion by Fragstat and hotspot analysis. The results show that: (1) The average soil erosion rate decreased from 2000 to 2020. Soil erosion is severe in the mountainous areas of western Hubei province, while it is less severe in the central plains. (2) Land-cover type, precipitation, and normalized difference vegetation index are the most influencing factors of soil erosion in 2000–2010, 2015, and 2020, respectively. (3) The aggregation index values at the town scale are higher than those at the city and county scales, while the fractal dimension index values at the town scale are lower, which indicates that soil erosion projects are most efficient when the project unit is ‘town’. (4) At the town scale, if the hotspot area (6.84% of the total area) is treated as the protection target, it can reduce 50.42% of the total soil erosion of Hubei province. Hotspots of soil erosion overlap with high erosion zones, mainly in the northwestern, northeastern, and southwestern parts of Hubei province in 2000, while the hotspots in northwestern Hubei disappear in 2020. In conclusion, land managers in Hubei should optimize the land-use structure, soil and water conservation in slope land, and eco-engineering controls at the town scale.

Section: Discussionmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

The Link between Landscape Characteristics and Soil Losses Rates over a Range of Spatiotemporal Scales: Hubei Province, China

Yong

Wang

et al. 2021

“…In recent years, rainfall erosion in the hilly and gully region of Loess Plateau has been intense [ 67 ]. Under the action of geological movement, geological disasters, such as landslides, plateau collapse, and ground subsidence, have occurred frequently, which poses a threat to the lives and property safety of residents and increases the difficulty of engineering construction [ 68 , 69 ]. In addition, the current land use limits the development of future construction to a certain extent.…”

Section: Methodsmentioning

confidence: 99%

Study of Township Construction Land Carrying Capacity and Spatial Pattern Matching in Loess Plateau Hilly and Gully Region: A Case of Xifeng in China

Zhao

et al. 2022

With the acceleration of urbanization, the construction land scale of urban and rural areas is constantly expanding, which leads to contradiction and conflict between territorial development and ecological protection becoming more and more serious. Therefore, as an important unit of county (district), and even urban and rural, development, the study on land resource carrying capacity and the rationality of the development can provide some basis for developing the optimal strategies of differential territorial space. Taking Xifeng, Gansu Province, China as the research area, this study constructs the evaluation index system of township construction land carrying capacity from the three dimensions of ecological protection, natural environment, and social economy. It evaluates the suitability of township construction land by the means of a comprehensive scoring method and discusses the carrying capacity and spatial pattern matching of township construction land based on the suitability evaluation results. The results showed that: (1) the spatial difference of suitability of construction land is obvious, which is higher in the city center than in the surrounding areas; (2) the comprehensive carrying capacity of township construction land is 52.62%, and different townships range from 3.78% to 13.15%. It is different between towns; (3) on the whole, the condition of township construction land is well-developed, and the main distribution forms are flaky, banded, and dotted. (4) There is a positive correlation between spatial matching and carrying capacity. The carrying capacity should be considered in regional development to avoid overdevelopment. It can provide a basis for optimizing the territorial spatial layout, strengthening the coordinated development among townships, and improving the comprehensive township carrying capacity in the Loess Plateau hilly and gully region.

“…Previous studies have shown that the morphological development of gullies depends on human activities [50][51][52], such as farming, vegetation restoration and other natural factors such as soil properties, land use, tectonic activity, vegetation cover, climate and rainfall, etc. [53][54][55]. In this article, soil properties and vegetation coverage were compared and analyzed according to the local topographic differences in the two study areas.…”

Section: The Influence Of Environmental Conditions On Gully Developmentmentioning

confidence: 99%

A Multi-Criteria Framework for Identification of Gully Developmental Stages Based on UAV Data—A Case Study in Yuanmou County, Yunnan Province, SW China

Lin

Bai

Luo

et al. 2022

Gully erosion is a common form of soil erosion in dry-hot valleys, and it often brings serious land degradation. A multi-criteria method integrating the characteristics of the longitudinal profile (LP), the cross profile (CP) and the knickpoints of gullies was applied to identify the development stage of gullies in Yuanmou County, Yunnan Province, in southwestern China. Firstly, based on the high-resolution data sources produced by an unmanned aerial vehicle (UAV), 50 gullies were selected as the typical ones in Tutujiliangzi and Shadi village. The LPs were extracted, and their morphological indices, information entropy and fitting functions were calculated. The morphological characteristics of the CPs and the presence or absence of knickpoints were recorded. The results show that the period of the gullies in Tutujiliangzi and Shadi is dominated by the deep incision period and the equilibrium adjustment period, which means that most gullies are in the period of the severe erosion stage. Among the gullies, 13 LPs’ morphological index is between 0.636 and 0.933, and the morphology of the LP presents an upward convex shape; the cross profiles are mainly V-shaped and U-shaped. Thirty-two LPs’ morphological index is between 1.005~2.384, which presents a slightly concave shape; the cross profiles are mainly repeated U-shapes. The remaining five LPs have a morphological index of 0.592, 0.462, 1.061, 1.344 and 0.888, respectively; the LPs of upstream and downstream are different. The LPs of the Tutujiliangzi gullies are nearly straight lines and slightly concave, while those of the Shadi village gullies are convex and nearly straight lines. The knickpoints and step-pools in Shadi village are more developed, while the gullies in Tutujiliangzi develop more rapidly. This study shows that in counties with similar conditions, these conditions such as temperature and precipitation, local topographic changes, soil properties and vegetation conditions have obvious effects on the development of gullies.