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Agricultural intensification has increased crop productivity but simplified production and reduced cropping system diversity. In recent decades, the intensified wheat–maize rotation in the North China Plain has sharply decreased the groundwater table, with associated environmental and biodiversity issues. Understanding whether increasing cropping system diversity stabilizes productivity, improves resilience, and reduces adverse environmental impacts is critical. This study quantified the water requirements of nine staple crops from 1960 to 2020, established 15 alternative crop rotations, and evaluated the resilience of each rotation in the Cangzhou area, a typical groundwater deletion funnel area. The results showed that reducing cropping density (harvests per year) from 2 to 1.5 decreased the average annual water requirement and irrigation demand by 14 % and 33 %, respectively. Summer soybean alternated with maize and rotated with wheat did not reduce groundwater use but increased profitability and protein production. Spring mung bean–summer millet-based multi-rotations had higher precipitation coupling degrees (8 % in wet years, 17 % in normal years, and 56 % in dry years) and profitability (1.1–2.4 times) than the wheat–maize rotation. The spring potato–summer millet rotation in one year had the greatest profitability, the highest equivalent yield to wheat, and the highest water use efficiency (WUE), while spring maize rotated with winter wheat–summer soybean performed best for protein content, energy output, and WUEs. This study identified 11 alternative rotations with a higher comprehensive evaluation index than the conventional wheat–maize rotation based on entropy-TOPSIS considering 12 indicators. Spring mungbean is not suitable for inclusion in the crop rotation when solely cultivated in one year due to mismatched rainfall. Beyond wheat and maize, soybean, millet, and potato are promising crops for innovative multi-year multi-crop rotations to enhance crop diversification, maximize system outputs, and minimize groundwater and energy depletion. This study's analysis could be extended to develop robust and diverse crop rotations with multiple co-benefits in other water-stressed agricultural regions. • Water requirements of nine staple crops from 1960 to 2020 was quantified. • 15 diversified crop rotations were redesigned and established. • Multi-dimensional outcomes of each rotation were evaluated for synergies and tradeoff. • Reducing cropping density mitigated groundwater table decline. • Wheat-maize rotations involving soybean, millet and potato achieved multiple co-benefits. [ABSTRACT FROM AUTHOR]

Numerical simulation has become a pivotal method in geotechnical engineering for analyzing rock failure. However, traditional model lacks comprehensive elastoplastic rock characterization. Therefore, a new finite-discrete element model using the Drucker-Prager criterion and cohesive elements based on a traction-separation law to accurately simulate elastoplastic rock breaking has been built. A scratch test simulation is conducted to describe the mechanical response and failure characteristics of the rock during the cutting process. Rock failure characteristics derived from numerical simulations align closely with experimental observations. These simulations successfully replicate both the ductile and brittle regimes observed during scratch tests. Furthermore, they provide insights into the primary driving factors behind rock failure under different regimes. Variation of cutting force and specific energy obtained from the model are entirely consistent with experimental results, with the specific energy decreasing following a −0.5 power law, thus explaining the energy dissipation rule of the specific energy decrease. In brittle regime, crush zones and the resulting rough shearing surface are observed, plastic damage is also found, revealing that the cutter tip is the key structure influencing them. The model established in this paper holds significant importance for rock mechanical property evaluation and the optimization design of cutter structures. [ABSTRACT FROM AUTHOR]