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Soil erosion on cropland is a result of the interaction between nature and human activities. The socioeconomic influencing factors of soil erosion have been less studied than the biophysical processes and previous studies have mainly focused on the impacts of local socioeconomic factors on soil erosion in the same region. However, since agricultural activities are densely connected to other socio-economic activities, the need for agricultural products from distant regions could potentially drive local soil erosion accompanying agricultural production. To the best of our knowledge, these telecoupling effects have not been studied. Here, we combined the Revised Universal Soil Loss Equation (RUSLE) and multiregional input-output analysis (MRIO) models to quantify the contribution of China's cross-provincial economic demand to local soil erosion at the provincial, sectoral, and supply chain levels. Our results show that a large amount of soil erosion in the southwest, northeast, and central regions is linked to the economic needs across provinces. Agriculture and food processing are the most important distant driving sectors. The driving effect of household consumption on soil erosion mainly occurs on shorter supply chains, while exports and capital formation drive soil erosion through longer chains. Our results indicate that local soil erosion management must consider the impact of distant agricultural product needs and coordinate food production and supply on a national scale to protect the ecological function of the land., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Soil conservation is of global importance, as accelerated soil erosion by human activity is a primary threat to ecosystem viability. However, the significance and role of soil conservation in reshaping landscape carbon (C) accounting has not been comprehensively integrated in the terrestrial C sink. Here, we present the first integrated assessment of the modified terrestrial C sink and aquatic C transport due to soil conservation for the semiarid Chinese Loess Plateau (CLP), the world's most vulnerable region to soil erosion. We show a surprisingly low terrestrial‐aquatic C transfer that offset the terrestrial net ecosystem productivity by only 7.5%, which we attribute to the effective implementation of soil conservation practices. Despite the highest soil erosion, the semiarid CLP acts as effective C sink at 43.2 ± 22.6 g C m−2 year−1, which is comparable to temperate forest in absorbing atmospheric CO2. Moreover, C burial in reservoirs has created an additional anthropogenic C sink of 2.9 ± 1.1 g C m−2 year−1. Our findings indicate that effective soil conservation can significantly increase landscape C sequestration capacity. The co‐benefits of soil conservation in erosion control and C sequestration have important implications for policy makers in other regions undergoing increasing erosion intensity to pursue environmental sustainability. Plain Language Summary: Aquatic export of terrestrial carbon (C) plays a significant role in modulating the magnitude of terrestrial C sink. Previous estimates of terrestrial C sink may be overestimated because not all C losses across heterogeneous landscapes are accurately determined and properly accounted for. This is particularly possible for catchments with high erosion and terrestrial‐aquatic C transfer potential. Meanwhile, soil conservation can greatly modify landscape C sequestration capacity. Thus, a more comprehensive assessment of net landscape C budget is needed that integrates aquatic export of terrestrial C while considering the role and significance of soil conservation. For the Chinese Loess Plateau in semiarid climates that once characterized the world's high soil erosion rate, we show a surprisingly low aquatic C transfer that offset the terrestrial C sink by only 7.5%, due largely to successful soil conservation in the past decades. Our findings suggest that effective implementation of soil conservation practices can substantially reduce terrestrial‐aquatic C transfer and enhance the landscape C sequestration capacity. Key Points: The magnitude of terrestrial‐aquatic C transfer in influencing landscape‐scale C balance on the Chinese Loess Plateau (CLP) is assessedThe low reduction of terrestrial C sink by terrestrial‐aquatic C transfer on the CLP is largely due to soil conservationEffective implementation of soil conservation can substantially reduce terrestrial‐aquatic C transfer and enhance landscape C sink capacity [ABSTRACT FROM AUTHOR]

Abstract: Controlling soil hydrological processes and combating soil erosion on agricultural fields are high priorities for crop production and ecological environments. In this research, the effect of land application of rock fragments on surface runoff, subsurface runoff, infiltration and soil loss on Regosols had been investigated under field conditions using a portable rainfall simulator. Experimental twin-plot (two subplot with 1-m wide by 2-m long, 32% slope) with different rock fragment covers ranging from 0–40% were exposed to three rainfall intensities, low (57±2mmh-1), medium (91±3mmh-1), and high (122±5mmh-1). Fifteen treatments were conducted in the experiments in duplicates. Surface runoff, subsurface runoff, soil moisture and sediment were measured. Results show that surface rock fragment cover retarded surface runoff, increased infiltration and subsurface runoff, and diminished sediment concentration and soil loss. The final infiltration rates, which increased with increasing rock fragment covers, were 16.5–42.7mmh-1 at low intensity, 19.7–50.8mmh-1 at medium intensity and 23.8–56.4mmh-1 at high intensity. Compared with bare soils, surface runoff rates were reduced to 24%, 51% and 64% in soils with 40% rock fragment cover at low, medium and high intensity rainfall, respectively. Subsurface runoff volume was significantly higher and time to start subsurface runoff was shorter as surface rock fragment cover increased. Compared with bare soils, subsurface runoff coefficients increased to 3.5, 3.3 and 2.9 times in soils with 40% rock fragment cover at low, medium and high intensity, respectively. Sediment concentrations increased from 9.8gL-1 for 40% rock fragment cover under high intensity rainfall to 51.5gL-1 for bare soils with rain falling at high intensity. The erosion rate was <12gm-2 min-1 for soils with 40% rock fragment cover, even when rainfall intensity was high, while it was >15gm-2 min-1 for bare soils under low intensity. The relationship between rock fragment cover and soil loss ratio can be expressed by an exponential function with a high degree of reliability, regardless of rainfall intensities. Overall, results indicate the surface rock fragments can be influential in shaping hydrological processes and soil loss from sloping farmland. [Copyright &y& Elsevier]

Socioeconomic factors are key driving forces for the occurrence and development of soil erosion, but their effects are not well understood. To analyse the relationship between the socioeconomic system and soil erosion, a framework was proposed and validated with structural equation modelling. Population pressure, economic development, agricultural inputs and outputs and soil erosion are latent variables of the framework. A case study was conducted in Jiangxi Province. The results showed that economic development was the key controlling factor and that agricultural output was the main promoting factor for soil erosion, with path coefficients of −1.321 and 1.609 in 1995 and -0.624 and 0.453 in 2010, respectively. This implied that the contradiction between socioeconomic development and ecological protection was alleviated during the study period. Agricultural input controlled severe soil erosion (-‍0.322) while promoting mild soil erosion (0.095), which indicated that more attention should be paid to the adverse impact of excessive agricultural inputs on soil erosion control. The identification of the socioeconomic driving forces of regional soil erosion could help adjust the development strategy and mitigate the negative effects of economic development on soil erosion control and ecological conservation. • Latent socio-economic variables have considerable influences on soil erosion. • Economic development is the most important driving force of soil erosion. • The promotional effect of surplus inputs on mild soil erosion should be of concern. • Structural equation modelling is a suitable framework to decouple this relationship.. • Contradiction between socio-economy and soil erosion have been alleviated in Jiangxi. [ABSTRACT FROM AUTHOR]

Agricultural production in China is mainly decentralized, small in size, and involved by independent single households. Farmers are the main implementers of soil erosion control projects. Their willingness and abilities, which are crucial to the effectiveness of these projects, are closely related to their social networks. However, the relationship between farmers' social networks and soil erosion control remains unclear. Hengxi, a typical village in Jiangxi Province, China, was used as a case study. Traditional- and new-type of farmers' social networks were built according to the planting structures based on survey data. The results showed that both types of networks had the characteristics of small-world network and scale-free network. The ability to obtain and dispense information was the significant distinction between the two networks. The dealer was an influential key node in both networks. The government agencies were key nodes in the new-type network but not in the traditional-type network, which made it difficult for traditional farmers to obtain indispensable information about soil erosion control. The characteristics of farmers and their corresponding networks had significant influences on their awareness of soil erosion. Soil erosion management projects could be deployed smoothly by the key farmers and government agencies in the new-type social network, but difficultly in the traditional-type social network. To improve the effectiveness of soil erosion control projects, cooperation with dealers is important for government agencies. • Characteristics of farmers' social networks are distinct based on planting structure. • Information diffusion is more efficient in new-type social network. • Betweenness centrality affects farmers' awareness of soil and water conservation. • Government agencies should undertake proper roles in traditional-type social network. [ABSTRACT FROM AUTHOR]