Sophora alopecuroides L., a perennial herb in the arid and semi-arid regions of northwest China, has the ecological functions of windbreaking and sand fixation and high medicinal value. In recent years, global warming and human activities have led to changes in suitable habitats for S. alopecuroides, which may affect the accumulation of natural products. In this study, MaxEnt 3.4 and ArcGIS 10.4 software were used to predict the distribution of potentially suitable habitats for S. alopecuroides in China under climate change. Furthermore, the geographical distribution of S. alopecuroides as affected by human activities, the differences in the content of natural products of S. alopecuroides between different suitable habitats, and the correlation between natural products and environmental factors were analyzed. The results showed that suitable habitats for S. alopecuroides were projected to expand in the future, and the major environmental factors were temperature (Bio1), rainfall (Bio18), and soil pH (pH). When Bio1, Bio18, and pH were 8.4283 °C, 7.1968 mm, and 9.9331, respectively, the distribution probability (P) of S. alopecuroides was the highest. After adding a human activity factor, the accuracy of the model prediction results was improved, and the area of suitable habitats was greatly reduced, showing a fragmented pattern. Meanwhile, habitat suitability had a specific effect on the content of natural products in S. alopecuroides. Specifically, the content of natural products in S. alopecuroides in wild habitats was higher than that in artificial cultivation, and highly suitable habitats showed higher contents than those in non-highly suitable habitats. The contents of total alkaloids and total flavonoids were positively correlated with human activities and negatively correlated with land use types. Among them, total alkaloids were negatively correlated with aspect, and total flavonoids were positively correlated with aspect. In addition, it is suggested that Xinjiang should be the priority planting area for S. alopecuroides in China, and priority should be given to protection measures in the Alashan area. Overall, this study provides an important foundation for the determination of priority planting areas and resource protection for S. alopecuroides.

Glycyrrhiza uralensis, Glycyrrhiza glabra, and Glycyrrhiza inflata are significant medicinal plants in traditional Chinese medicine. They also contribute to ecological protection and restoration in the arid and semi-arid regions of Northwest China. This study employed the MaxEnt model to predict the potential habitats of these three species in China under climate change, and examined the relationship between their distribution and desert ecosystems. The results indicated that (1) G. uralensis has a broad distribution, primarily in Northeast, North, and Northwest China. Glycyrrhiza glabra and G. inflata are predominantly found in the northwest provinces. (2) Under current climate conditions, the distribution of the most suitable habitats for these species closely mirrors that of deserts. However, future climate change is expected to reduce the spatial range of all three species. (3) These three species are effective psammophytes, capable of thriving in desert margins and other highly suitable habitats on a large scale. This research offers a theoretical basis for the conservation of plant resources, the restoration and protection of desertified areas, and the advancement of deserticulture.

Hippophae rhamnoides L. is an ecologically and medicinally significant species widely distributed across Eurasia, the suitable habitat of H. rhamnoides subsp. sinensis (is hereinafter referred to as sinensis) is concentrated in Northwest and Southwest China (approximately 34–40° N, 100–115° E). H. rhamnoides subsp. yunnanensis (hereinafter referred to as yunnanensis) is mainly distributed in the Hengduan Mountains and surrounding areas (approximately 25–30° N, 98–103° E). H. rhamnoides subsp. mongolica (hereinafter referred to as mongolica) is native to Central Asia to Siberia and is mainly distributed in Northern Xinjiang and Western Inner Mongolia in China (approximately 40–50° N, 100–120° E). H. rhamnoides subsp. turkestanica (hereinafter referred to as turkestanica) is mainly distributed in Western Xinjiang (approximately 40–45° N, 70–85° E). Climate change poses a considerable challenge, affecting its distribution and leading to shifts in its habitat ranges. This study applies the MaxEnt model to assess climate-driven distribution patterns of Hippophae species in China, and predicts current and future suitable habitats under climate change scenarios. This study employs the MaxEnt model and ArcGIS to simulate the potential distribution of four subspecies of H. rhamnoides during the current period and future projections under scenarios SSP1–2.6 and SSP5–8.5. The analysis reveals that the distributions of sinensis, mongolica, yunnanensis, and turkestanica are influenced primarily by climate variables such as temperature and precipitation, while yunnanensis is predominantly restricted by altitude. Future projections indicate that under the extreme climate of SSP5–8.5, centroid migration will be disrupted; specifically, sinensis is expected to migrate northeast or oscillate, mongolica will expand southwest but be limited by desert steppe zones, and turkestanica may face risks associated with groundwater depletion. This study advocates for integrating climate, ecological, and genetic data into conservation planning, with an emphasis on groundwater restoration and exploring genetic resources for stress resilience. The insights offered here contribute significantly to understanding climate adaptation mechanisms in arid and mountainous ecosystems and guide biodiversity conservation efforts.

Hippophae rhamnoides subsp. turkestanica is mainly distributed in the mountains, valleys, and desert edges of Central Asia. It plays a vital role in maintaining ecological stability in arid and semiarid areas. In this study, the MaxEnt model was used to simulate the habitat suitability of H. rhamnoides subsp. turkestanica, and the key environmental factors affecting its distribution were identified. Additionally, we explored habitat sensitivity to climate change, and provided essential information for the conservation and management of this important subspecies in arid and semiarid regions. Under four different climate scenarios (SSP126, SSP245, SSP370, and SSP585) in 2040, 2060, 2080, and 2100, the prediction of habitat suitability and changes in species distribution centroids in the future were simulated. The results revealed that suitable habitats for H. rhamnoides subsp. turkestanica are primarily located in Tajikistan, Kyrgyzstan, China, Pakistan, and Afghanistan. Altitude (Alt), isothermality (bio3), and slope (Slo) emerged as the main environmental factors. Projections suggest a significant expansion in the total area of suitable habitat under future climate scenarios. By 2100, the suitable habitat areas under the SSP126, SSP245, SSP370, and SSP585 scenarios will reach 10,526,800 km², 12,930,200 km², 15,449,900 km² and 14,504,800 km², respectively. In addition, a slight northwestward shift was observed in the distribution centroid. These findings provide important insights for conservation efforts aimed at protecting H. rhamnoides subsp. turkestanica and supporting its biodiversity. By understanding the factors affecting habitat suitability and predicting changes in climate scenarios, this study provides valuable guidance for developing long-term conservation strategies.

The effective management of water and nitrogen is crucial in the artificial cultivation of medicinal plants. Sophora alopecuroides, a perennial herbaceous plant in the Fabaceae family, is extensively used in medicine, with alkaloids as its primary bioactive constituents. Nevertheless, there remains a significant knowledge gap regarding how rhizospheric microbial communities respond to varying water and nitrogen conditions and their intricate relationships with soil environments and the growth of S. alopecuroides. In this study, two-year-old S. alopecuroides were used in a two-factor, three-level water-nitrogen interaction experiment. The irrigation levels included W1 (30–35% of maximum water holding capacity), W2 (50–55%), and W3 (70–75%), while nitrogen levels comprised N1 (32 mg/kg), N2 (64 mg/kg), and N3 (128 mg/kg). The study assessed plant growth indicators, total alkaloid content, and rhizospheric soil physicochemical parameters of S. alopecuroides. High-throughput sequencing (16S rRNA and ITS) was employed to analyze variations in rhizospheric microbial community composition and structure. The results showed that Proteobacteria and Ascomycota are the predominant bacterial and fungal phyla in the rhizosphere microbial community of S. alopecuroides. The highest biomass and alkaloid accumulation of S. alopecuroides were observed under the N1W3 treatment (50% nitrogen application and 70–75% of maximum water holding capacity). Specifically, six bacterial genus-level biomarkers (TRA3_20, MND1, env_OPS_17, SBR1031, Haliangium, S0134_terrestrial_group) and six fungal genus-level biomarkers (Pseudeurotium, Rhizophagus, Patinella, Pseudeurotium, Patinella, Rhizophagus) were identified under the N1W3 treatment condition. In the partial least squares path modeling (PLS-PM), water and nitrogen treatments demonstrated markedly positive direct effects on soil physicochemical parameters (p < 0.01), while showing significant negative direct impacts on alkaloid accumulation and plant growth indicators (p < 0.05). Soil physicochemical parameters, in turn, significantly negatively affected the rhizosphere fungal community (p < 0.05). Additionally, the rhizosphere fungal community exhibited highly significant negative direct effects on both the plant growth indicators and total alkaloid content of S. alopecuroides (p < 0.01). This study provides new insights into the interactions among rhizosphere soil environment, rhizosphere microbiota, plant growth, and alkaloid accumulation under water and nitrogen regulation, offering a scientific basis for the water and nitrogen management in the cultivation of S. alopecuroides.