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China's Grain‐for‐Green Program (GFGP) motivates conversion from steep slope cropland to forest or grassland to reverse serious land degradation. However, impoverished farmers potentially persist with inefficient slope farming for survival, thereby threatening the sustainable GFGP efforts. Consequently, a strategy for balancing farming and vegetation restoration from a spatial optimization perspective is necessary. Here, we selected two catchments with high and low agricultural intensity in the loess hilly and gully regions for a case study. Spatial analysis and binary logistic regression models were used to clarify the effects of topography, accessibility, and location factors on cropland distribution and explore spatially optimized cropland distribution. The results show that steep slope cropland is still widespread, of which cropland with slopes >15° accounts for 46.7% and 34.7% in the two catchments, respectively. Residences and roads significantly impact steep slope cropland distribution, and around 80% of cropland with slopes >15° is distributed within 200 m from residences or 100 m from roads. In cropland redistribution scenarios, cropland with slopes >25° and >15° can be redistributed to gentler slopes while maintaining cropland areas in catchments with high and low agricultural intensity. Correspondingly, 38.8% and 81.2%, respectively, of simulated cropland on gentle slopes needs optimized attributes such as accessibility in order to be priorities of farmers. Our research provides new insights into GFGP strategies for steep slope cropland restoration in catchments with different agricultural intensities, thereby advancing sustainable farming and vegetation restoration in China's mountainous regions. [ABSTRACT FROM AUTHOR]

China has implemented the world's largest‐ever vegetation restoration program in marginal mountainous areas to sustain life on land. However, land competition between the demand for grain and the need for green has threatened sustainable vegetation restoration. Here, focusing on China's marginal mountainous areas with the highest density of slope cropland, we explore the optimal solution in the trade‐offs between green and grain. We find that current vegetation restoration strategies are not sufficiently optimized, which may threaten the survival and development of local farmers and in turn destroy existing vegetation restoration achievements. Through adjusting vegetation restoration objectives carefully tailored to local conditions, the population experiencing grain shortages can be greatly reduced by 51–66% (from 18.26 million to 6.29–8.90 million) compared with the current scheme. The optimal design will alleviate the conflict between grain and green, thereby promoting sustainable ecological restoration in China. Our research provides an important reference for the world's mountainous areas to achieve a win‐win situation between green and grain. Plain Language Summary: Vegetation restoration in China has made remarkable achievements in recent years. However, the sustainability of these vegetation restoration programs has been questioned and challenged. Combined with spatial statistics and scenario analysis for analyzing the trade‐offs between green and grain, we find that the current vegetation restoration strategies in China's mountainous areas are not sufficiently optimized, which may affect the sustainability of vegetation restoration programs. Vegetation restoration strategies adapted to local conditions can reduce the risk of grain shortage for 9.30–11.97 million farmers, and contribute to a more balanced development and the sustainability of vegetation restoration in mountainous areas. Key Points: Chinese farmers rely heavily on slope cropland and self‐sufficient farming in marginal mountainous areasCurrent vegetation restoration strategies are not sufficiently optimized, which may affect farmers' livelihood in mountainous areasPlanning tailored to local conditions can alleviate the conflict between grain and green, and promote sustainable vegetation restoration [ABSTRACT FROM AUTHOR]

Accurate information on crop type spatial distributions is crucial for yield estimation, agroecological modeling, and agrarian policy development. In comparison with moderate resolution (10–30 m) satellite images, very high-resolution (VHR, ≤ 1 m) images are superior at describing the spatial details and complex texture features of agricultural land. However, VHR images generally suffer from insufficient spatiotemporal coverage and high spectral variation in crop type, making fine-scale crop type mapping at regional or larger scales challenging. In this study, we developed a novel data-driven residual attention U-shape network (RAUNet) to identify crop types at the regional scale based on VHR images. RAUNet was adapted from UNet by introducing a residual module and a gated attention mechanism to strengthen the multilevel representation of crop features from VHR images. We selected rice-crayfish fields (RCFs) in Hubei Province, China, as the case crop type and area to test the performance of RAUNet. Seven models, including RAUNet pan , ResUNet, AttnUNet, UNet, DeepLabV3 + and random forest at the pixel and object levels, were adopted for comparison with RAUNet. Moreover, the model transferability was evaluated over regions with different agricultural landscapes. Our results showed that RAUNet-derived RCF maps obtained an average F1-score and MCC of 0.90 and 0.85 at different cultivation stages, which significantly outperformed other methods. Additionally, RAUNet had good spatiotemporal transferability, with an average F1-score and MCC of 0.93 and 0.88 in four transfer areas. The visualization results of the attention weights indicated RAUNet's prominent capability in combining useful and relevant information from different feature levels to produce refinement predictions for the target crop type. Furthermore, the high-level features derived from RAUNet can well separate RCFs and non-RCFs over different landscapes, which were also consistent across different cultivation periods. These encouraging results suggest that RAUNet works well for fine-scale crop type mapping in smallholder farming systems, and it is an efficient method for land cover mapping based on VHR images at the regional scale. [ABSTRACT FROM AUTHOR]

Cropland soil erosion is primarily caused by agricultural production and indirectly altered by consumption patterns. A well-developed grain trade system transfers grain products to distant locations, away from their place of origin where soil erosion may have occurred. Evidence-based policies to control soil erosion can be developed by holding consumers responsible for the soil erosion caused by their consumption. However, there have been few systematic studies on cropland soil erosion that is embodied in grain trade. In this study, we estimated the soil erosion intensity (SEI) of grain production in each province of China from 1990 to 2020 by combining the Revised Universal Soil Loss Equation and socio-economic statistics. We also constructed an interprovincial grain trade network using linear programming techniques and analyzed the cropland soil erosion associated with the interprovincial grain trade. The results showed a rise in national cropland soil erosion attributed to grain production from 5.36×108 t in 1990 to 7.56×108 t in 2020. In particular, those embodied in interprovincial grain trade increased from 0.94×108 t in 1990 to 3.52×108 t in 2020. Nationally, about 10.72% of soil erosion exports in 2020 was from provinces with lower-than-average SEI, compared to 18.42% in 1990, indicating that current patterns of grain production and consumption are unfavorable for erosion control. Accordingly, measures have been proposed to build a soil erosion control system that includes consumers, such as changing farming practices, optimizing agricultural layout, promoting technology export and establishing a provincial compensation mechanism. [Display omitted] • Trade was prominent and insufficiently explored driver for cropland soil erosion. • RUSLE and grain trade network were utilized to estimate embodied soil erosion. • Mismatch between production and consumption increased embodied soil erosion. • Soil erosion burden mainly shifted from south with high SEI to north with low SEI. • Current provincial grain trade patterns were not conducive to soil erosion control. [ABSTRACT FROM AUTHOR]

Cropland soil erosion is a major threat to global agricultural sustainability. Compared with the well-studied natural factors of soil erosion, socioeconomic factors have just begun to be considered. The major obstacle is that the soil erosion of different crops has not been accounted for and connected to socioeconomic activities. This study adopted the revised universal soil loss equation (RUSLE) and the environmentally extended multiregional input-output (EE-MRIO) model to account for soil erosion on cropland from the production, consumption, and income perspectives at the provincial and sectoral levels in China. The results showed the major responsible agents in a synthetic view. On the production side, the Yunnan-Kweichow Plateau and surrounding hills of the Sichuan Basin, the Chinese grain bases located in northeastern and central China, and the Loess Plateau were the major regions that caused the most cropland soil erosion. On the consumption side, the national final demand for Sichuan, Yunnan, Shandong, Henan, and other provinces with high production-based cropland soil erosion (PBE) values per se pulled remarkable cropland soil erosion. On the income side, the crucial provinces into which the national primary input enabled notable cropland soil erosion were still those areas with serious cropland soil erosion. From the industrial perspective, the direct effects of human primary inputs into agriculture and the demand for agricultural products played the dominant role. In addition, Cereal and BOP (beans, oil and potatoes) were the most important among the agricultural sectors. The effects of the nonagricultural sectors, especially the manufacture of foods and tobacco (MFT) and the chemical industry (CI), on cropland soil erosion also cannot be ignored. Our results indicated that accounting from multiple perspectives could inform the better management of cropland soil erosion from a more comprehensive perspective. To the best of our knowledge, this study is the first to consider the accounting of cropland soil erosion in China from multiple perspectives. Tailored packages of measures should be established based on different patterns of areas with serious cropland soil erosion. [Display omitted] • Cropland soil erosion accounting was based on a multi-regional input-output table. • Multiple perspectives' accounting shows the major responsible agents for soil loss. • Crops in different regions also were the key to tackle cropland soil erosion. • Cropland soil erosion control cannot just narrow down to four agricultural sectors. • Cropland soil erosion is not a local phenomenon but a macroscopic problem. [ABSTRACT FROM AUTHOR]

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. [Display omitted] • Cropland soil erosion was linked to a multi-regional input-output table. • 28.19% of cropland soil erosion was driven by distant final demand. • Ten provinces had more than 1/4 of their soil erosion driven by other provinces' consumption. • Agriculture, Food Processing, and Construction contributed 72.28% telecouped erosion. • The telecoupled share increases along supply chains from 19.60% (tier 0) to 33.70% (tier 6). [ABSTRACT FROM AUTHOR]