Acorus calamus, a perennial emergent herb, is highly valued for its ornamental appeal, water purification ability, and medicinal properties. However, there is a significant contradiction between the rapidly increasing demand for A. calamus and the diminishing wild resources. Understanding its geographical distribution and the influence of global climate change on its geographical distribution is imperative for establishing a theoretical framework for the conservation of natural resources and the expansion of its cultivation. In this study, 266 distribution records of A. calamus and 18 selected key environmental factors were utilized to construct an optimal MaxEnt model via the ENMeval package. We simulated the potential geographical distributions under current conditions and under three different climate scenarios (SSP126, SSP370, and SSP585) in the 2050s, 2070s, and 2090s. Additionally, we employed the jackknife method and response curves to identify the environmental factors with the greatest influence on the distribution of A. calamus, and their response intervals. The results indicate that the regularization multiplier (RM) of 3.5 and the feature combinations (FC) of linear (L), quadratic (Q), hinge (H), and product (P) are the optimal model parameter combinations. With these parameters, the model predictions are highly accurate, and the consistency of the results is significant. The dominant environmental factors and their thresholds affecting the distribution of A. calamus are the precipitation of the wettest month (≥109.87 mm), human footprint (≥5.39), annual precipitation (≥388.56 mm), and mean diurnal range (≤12.83 °C). The primary land use types include rivers and channels, reservoirs and ponds, lakes, urban areas, marshes, other constructed lands, rice fields, forested areas, and shrublands. Under current climate conditions, the suitable geographical distribution of A. calamus in China is clearly located east of the 400 mm precipitation line, with high- and low-suitability areas covering 121.12 × 10⁴ km², and 164.20 × 10⁴ km², respectively. Under future climate conditions, both high- and low- suitability areas are projected to increase significantly, whereas unsuitable areas are expected to decrease, with the centroid of each suitability zone shifting northward. This study provides a theoretical foundation for sustainable utilization, future production planning, and the development of conservation strategies for wild germplasm resources of A. calamus.

The plant species used in constructed wetlands are mainly aquatic herbaceous, most of which tend to die during winter in subtropicsal areas. At present, very few studies have examined the performance of woody plants in constructed wetlands. In order to increase plant diversity and improve purification ability of vertical-flow constructed wetland during winter, 10 woody plant species were tested by establishing the microcosms simulating vertical-flow constructed wetlands. Their applicability was integrally evaluated, on basis of their adaptability, rhizospheric enzyme activity, and rhizospheric microbial diversity. The results showed that (1) seven woody plant species, Adina rubella, Salix rosthornii, Callicarpa dichotoma, Nerium oleander, Hibiscus mutabilis, Ligustrum obtusifolium, and Ligustrum lucidum could survive in the simulated vertical-flow constructed wetland; (2) N. oleander and C. dichotoma had higher nitrogen (N) and phosphorous (P) absorption capacity; (3) according to the integral evaluation, N. oleander, C. dichotoma, and S. rosthornii have excellent applicability for vertical-flow constructed wetland; A. rubella and H. mutabilis have moderate applicability; L. obtusifolium and L. lucidum have poor applicability; Ligustrum. japonicum "Howardii", Pittosporum. tobira and Distylium. buxifolium, were not applicable to vertical-flow constructed wetland. N. oleander, C. dichotoma, and S. rosthornii are recommended for application in vertical-flow constructed wetland.

Rhododendron simsii var. putuoense is a coastal-endemic plant with significant ecological and genetic resource value. Although its chloroplast genome (cpDNA) was recently characterized, its mitochondrial genome (mtDNA) remains unexplored. Here, we report the first complete assembly and annotation of the R. simsii var. putuoense mtDNA using PacBio HiFi long-read sequencing. The genome sequence is 658,161 bp in length, organized as two subgenomic linear molecules (a major one of 633,105 bp and a minor one of 25,056 bp), and encodes 33 protein-coding genes (PCGs), 26 tRNAs, three rRNAs and 323 ORFs. Repeat analysis revealed a predominance of dispersed repeats (72%), alongside 128 SSRs and 20 tandem repeats. The mtDNA exhibits a strong A/U-ending codon usage bias, with 463 RNA editing sites predicted. Six homologous segments (0.91% of the mtDNA) provide evidence of interorganellar gene transfer (IGT). Notably, pairwise K _a / K _s analysis revealed an elevated ratio in the matR gene, suggesting at lineage-specific evolutionary dynamics that warrant further site-specific codon model testing. Phylogenetic and synteny analyses further confirmed a close relationship with R. simsii , while revealing structural divergence consistent with ecological specialization. Overall, these findings deepen our understanding of mitochondrial genomic diversity within Rhododendron and establish a genetic framework for conserving lineage-specific resources in this ecologically significant variety.

Climate change is increasingly reshaping the distribution and long-term persistence of urban greening tree species, yet national-scale assessments of widely planted species in China remain limited. Salix babylonica is one of the most representative and extensively planted urban greening trees in China, but its future climate vulnerability and redistribution patterns are still poorly understood. In this study, we integrated 425 occurrence records and 16 environmental variables to project the potential distribution of S. babylonica under current and future (2050s, 2070s, and 2090s) climate scenarios across three shared socioeconomic pathways (SSP126, SSP370, and SSP585) using an optimized MaxEnt model. The optimized model demonstrated strong predictive performance and identified annual precipitation (≥309.64 mm), precipitation of the wettest month (≥82.01 mm), elevation (≤2251.24 m), mean temperature of the coldest quarter (≥−10.77 °C), annual mean temperature (≥3.94 °C), and minimum temperature of the coldest month (≥−19.11 °C) as the dominant environmental factors (threshold) constraining species distribution. Under the current climate, suitable habitats of S. babylonica are primarily distributed in East, Central, Southwest, and South China, with highly suitable habitats concentrated in the eastern and central plains. Under future climate scenarios, high suitability areas are projected to contract significantly and become progressively fragmented, with reductions ranging from 2.81% (2070s-SSP126) to 40.01% (2090s-SSP585), whereas medium and low suitability areas are projected to expand substantially, with increases ranging from 6.76% to 48.10%. The overall centroid of suitable habitats exhibits a consistent northward shift across scenarios. These results indicate that climate change will not simply expand the potential distribution of S. babylonica, but will reorganize habitat quality and increase long-term risks for its continued use in urban greening. Our findings provide a spatially explicit basis for climate-adaptive urban forestry planning and support risk-differentiated management, including the conservation of stable core areas, monitoring of declining risk zones, and cautious introduction trials in newly emerging suitable areas.