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Grassland degradation is a serious ecological issue in the farming–pastoral ecotone of northern China. Utilizing native grasses for the restoration of degraded grasslands is an effective technological approach. Leymus secalinus is a superior indigenous grass species for grassland ecological restoration in northern China. Therefore, the excavation of potential distribution areas of L. secalinus and important ecological factors affecting its distribution is crucial for grassland conservation and restoration of degraded grasslands. Based on 357 data points collected on the natural distribution of L. secalinus, this study employs the jackknife method and Pearson correlation analysis to screen out 23 variables affecting its spatial distribution. The MaxEnt model was used herein to predict the current suitable distribution area of L. secalinus and the suitable distribution of L. secalinus under different SSP scenarios (SSP1-26, SSP2-45, and SSP5-85) for future climate. The results showed the following: (1) Mean diurnal temperature range, annual mean temperature, precipitation of the wettest quarter, and elevation are the major factors impacting the distribution of L. secalinus. (2) Under the current climatic conditions, L. secalinus is mainly distributed in the farming–pastoral ecotone of northern China; in addition, certain suitable areas also exist in parts of Xinjiang, Tibet, Sichuan, Heilongjiang, and Jilin. (3) Under future climate change scenarios, the suitable areas for L. secalinus are generally the same as at present, with slight changes in area under different scenarios, with the largest expansion of 97,222 km2 of suitable area in 2021–2040 under the SSP1-26 scenario and the largest shrinkage of potential suitable area in 2061–2080 under the SSP2-45 scenario, with 87,983 km2. Notably, the northern boundary of the middle- and high-suitability areas is reduced, while the northeastern boundary and some areas of Heilongjiang and Jilin are expanded. The results of this study revealed the suitable climatic conditions and potential distribution range of L. secalinus, which can provide a reference for the conservation, introduction, and cultivation of L. secalinus in new ecological zones, avoiding the blind introduction of inappropriate habitats, and is also crucial for sustaining the economic benefits associated with L. secalinus ecological services.

A spherical weathering body, also called a boulder, is an element of complex geological strata and presents a significant challenge to tunnelling by a tunnel-boring machine (TBM). In this study, ground-based drilling and blasting were used to precondition boulders. To determine the specific charge needed for preconditioning blasting, model blasts were conducted, and the relationships among the specific charge, fragment size, and overburden depth in the model blasts were investigated. The determined specific charge from the model blasts was then modified by considering the overburden depth and used to precondition the boulders for practical TBM tunnelling. The results indicate the following: (1) model blasts were effective in determining the correct specific charge and predicting boulder fragment sizes resulting from blasting; (2) the boulders met in practical TBM tunnelling were successfully preconditioned by using the determined specific charge; (3) the determined specific charge was 3.26 kg/m3, corresponding to an average fragment size 4.5 cm with an overburden of zero and increased with increasing overburden; (4) fragment sizes were dependent on both the specific charge and overburden depth. Our conclusions can be used to accurately determine the specific charge instead of empirical formulas.

In the context of climate change, the frequency and intensity of extreme weather events are increasing, environmental pollution and global warming are exacerbated by anthropogenic activities, and plants will experience a more complex and variable environment of stress combinations. Research on plant responses to stress combinations is crucial for the development and utilization of climate-adaptive plants. Recently, the concept of stress combinations has been expanded from simple to multifactorial stress combinations (MFSCs). Researchers have realized the complexity and necessity of stress combination research and have extensively employed composite gradient methods, multi-omics techniques, and interdisciplinary approaches to integrate laboratory and field experiments. Researchers have studied the response mechanisms of plant reactive oxygen species (ROS), phytohormones, transcription factors (TFs), and other response mechanisms under stress combinations and reached some generalized conclusions. In this article, we focus on the research progress and methodological dynamics of plant responses to stress combinations and propose key scientific questions that are crucial to address, in the context of plant responses to stress assemblages, conserving biodiversity, and ensuring food security. We can enhance the search for universal pathways, identify targets for stress combinations, explore adaptive genetic responses, and leverage high-technology research. This is in pursuit of cultivating plants with greater tolerance to stress combinations and enabling their adaptation to and mitigation of the impacts of climate change.