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Oreocharis argyreia var. angustifolia of Gesneriaceae is widely distributed in South China, including Guangdong, Guangxi, Hunan, and Jiangxi provinces. However, genetic information of this species is limited, further contributing to the taxonomic complications surrounding this species. Thus, in this study, we assembled and characterized the complete chloroplast genome of O. argyreia var. angustifolia as a genomic resource for future studies. The complete plastid genome was 154,675 bp in size, with a pair of inverted repeat regions of 25,329 bp each, separating the 85,977-bp large and 18,040-bp small single copy regions. A total of 131 genes were predicted, consisting of 86 protein-coding, 37 tRNA, and eight rRNA genes. The overall GC content was 37.6%. Phylogenetic analysis based on 79 shared unique CDS resulted in a fully resolved phylogenetic tree using both the maximum likelihood and Bayesian inference methods. Based on current circumscription, both methods indicated that Oreocharis is monophyletic; O. argyreia var. angustifolia diverged after O. chienii, which then followed by the divergence of the other three species included namely, O. continifolia, O. esquirolii, and O. mileensis. The genomic data obtained will be useful for future studies on the phylogenetics and evolution of Gesneriaceae. [ABSTRACT FROM AUTHOR]

• Mild soil erosion (0–176.26 t hm−2 a−1) occurred in the Nanliao River watershed. • Soil total P (STP) content showed moderate variability (0.06–1.19 g/kg). • There was a negative correlation between STP content and soil erosion. • Elevation, soil particle size, and pH were the main factors influencing STP content. Soil erosion can change the migration and deposition patterns of soil particles and alter the regional geographic environment; therefore, it plays an important role in the biogeochemical cycle of soil total phosphorus (STP). Quantifying the influence of environmental factors on STP content under soil erosion is critical for understanding the lateral transfer of STP from soil. Here, we explored the influence of environmental factors on STP content under different levels of soil erosion in the small watershed of Nanliao River, a tributary of Xiu River in the western part of Poyang Lake Plain in Jiangxi Province, China. Soil erosion ranged from 0 to 176.26 t hm−2 a−1 (15.41 t hm−2 a−1 on average) across the watershed in 2018, indicating a mild erosion level on the whole. The STP content varied between 0.06 and 1.19 g/kg (0.6 g/kg on average) with a coefficient of variation of 43.33%, indicating moderate variation. An exponential model with a small nugget effect (7.35%) and a small range (2.25 km) could estimate 86.5% of spatial variability in STP content. The STP content showed a strong spatial autocorrelation, and the soil rich in STP was mostly distributed along the Nanliao River. There was a negative correlation between STP content and soil erosion (r = –0.149, P < 0.01). Each of the 10 selected environmental factors could explain 2.7–21.3% of spatial variability in STP content. Elevation, soil particle size, soil pH, and their interactions with other factors were the main factors influencing STP content, although their influence differed across various erosion levels. This study could provide useful data for controlling STP loss and reducing the impacts of soil erosion on the ecological environment in the Poyang Lake Plain. [ABSTRACT FROM AUTHOR]