Great efforts have been made to improve the soil and water conservation capacity by restoring plant communities in different climatic and land-use types. However, how to select suitable species from local species pools that not only adapt to different site environments, but also achieve certain soil and water conservation capacities is a great challenge in vegetation restoration for practitioners and scientists. So far, little attention has been paid to plant functional response and effect traits related to environment resource and ecosystem functions. In this study, together with soil properties and ecohydrological functions, we measured the seven plant functional traits for the most common species in different restoration communities in a subtropical mountain ecosystem. Multivariate optimization analyses were performed to identify the functional effect types and functional response types based on specific plant traits. We found that the community-weighted means of traits differed significantly among the four community types, and the plant functional traits were strongly linked with soil physicochemical properties and ecohydrological functions. Based on three optimal effect traits (specific leaf area, leaf size, and specific root length) and two response traits (specific leaf area and leaf nitrogen concentration), seven functional effect types in relation to the soil and water conservation capacity (interception of canopy and stemflow, maximum water-holding capacity of litter, maximum water-holding capacity of soil, soil surface runoff, and soil erosion) and two plant functional response types to soil physicochemical properties were identified. The redundancy analysis showed that the sum of all canonical eigenvalues only accounted for 21.6% of the variation in functional response types, which suggests that community effects on soil and water conservation cannot explain the overall structure of community responses related to soil resources. The eight overlapping species between the plant functional response types and functional effect types were ultimately selected as the key species for vegetation restoration. Based on the above results, we offer an ecological basis for choosing the appropriate species based on functional traits, which may be very helpful for practitioners involved in ecological restoration and management.

Understanding the influence of invasive species on community composition and ecosystem properties is necessary to maintain ecosystem functions. However, little is known about how understory plant communities and soil nutrients respond to invasion under different land cover types. Here, we investigated the effects of the invasive species Ageratina adenophora on the species and functional diversity of understory communities and on soil phosphorus (P) status in three forest types: CF, coniferous forest; MF, coniferous and broadleaf mixed forest; and EBF, evergreen broadleaf forest. We found that the species and functional diversity indices of the understory community significantly varied by forest type. Among the invaded plots, the greatest decrease in functional diversity (functional richness, functional divergence, and functional dispersion) and biotic homogenization were found in the CF rather than the MF or EBF. In addition, the invasion by A. adenophora significantly increased the soil NaHCO₃-extractable inorganic P and organic P in the MF and EBF, respectively, while obviously decreasing the soil maximum P sorption capacity and maximum buffering capacity in the CF. However, the changes in the species and functional attributes of the understory communities were weakly associated with changes in the soil P status, probably because of the different response times to invasion in different forest types. The implication of these changes for ecosystem structure and function must be separately considered when predicting and managing invasion at a landscape scale.

Although phytoremediation is the main method for P-removal and maintaining ecosystem balance in geological phosphorus-enriched soils (PES), little is known about the structure and function of microbial communities in PES. Interactions between plants and soil microorganisms mainly occur in the rhizosphere. The aim of this work was to investigate the composition and diversity of bacterial communities found in rhizosphere soils associated with the following three dominant plant species: Erianthus rufipilus, Coriaria nepalensis, and Pinus yunnanensis. In addition, we compared these rhizosphere bacterial communities with those derived from bulk soils and grassland plots in PES from the Dianchi Lake basin of southwestern China. The Illumina MiSeq platform for high-throughput sequencing of 16S rRNA was used for the taxonomy and the analysis of soil bacterial communities. The results showed higher bacterial diversity and nutrient content in rhizosphere soils as compared with bulk soils. Rhizosphere bacteria were predominantly comprised of Proteobacteria (24.43%) and Acidobacteria (21.09%), followed by Verrucomicrobia (19.48%) and Planctomycetes (9.20%). A comparison of rhizosphere soils of the selected plant species in our study and the grassland plots showed that Acidobacteria were the most abundant in the rhizosphere soil of E. rufipilus; Bradyrhizobiaceae and Rhizobiaceae in the order Rhizobiales from C. nepalensis were found to have the greatest abundance; and Verrucomicrobia and Planctomycetes were in higher abundance in P. yunnanensis rhizosphere soils and in grassland plots. A redundancy analysis revealed that bacterial abundance and diversity were mainly influenced by soil water content, soil organic matter, and total nitrogen.

Vegetation type is known to affect soil organic carbon (SOC) storage. However, the magnitudes and distributions of SOC sequestration and driving factors for different vegetation types are still largely unknown. Thus, we studied the changes in SOC fractions along soil profiles for different vegetation restoration types and their relationships with soil properties. We selected five vegetation types and collected soil samples from depth intervals of 0–10, 10–30, 30–60, and 60–90 cm. Five soil carbon fractions and the soil properties were tested to evaluate the soil carbon fraction distributions and influencing factors. Our results demonstrated that the concentrations of total organic carbon (TOC) and five carbon fractions were strongly affected by vegetation types and soil depths. The concentrations of all five soil carbon fractions in 0–10 cm depth were higher than those in the other three soil depths and generally increased with vegetation complexity. The Pearson correlations and redundancy analysis showed that the fractions of soil glomalin-related soil protein (GRSP) and Fe oxides as well as the soil bulk densities, were the most significant related to soil TOC levels and carbon fractions, which suggests that soil biochemical and physicochemical processes are among the most important mechanisms that contribute to SOC persistence. Considering the sensitive indices of the soil carbon variables and PCA results, soil permanganate oxidizable carbon (POXC) was considered to be the most sensitive index for differentiating the effects of vegetation types. These results provide important information regarding the distributions and driving factors of the carbon fractions that result from different vegetation restoration types and will help to improve our understanding of soil carbon sequestration during vegetation restoration processes.

Functional characteristics are increasingly used to evaluate the success of different vegetation restoration. Community functional diversity (FD) and the community-weighted mean (CWM), as two main complementary components, are closely linked to site environment and ecosystem functions. However, the patterns and driving factors of functional characteristics are still not clear in different vegetation restoration types. Here, four community restoration types (secondary shrubland, SL; Pinus yunnanensis forest, PF; mixed needle–broad-leaved forest, MF; natural secondary forest, NSF) were selected to investigate species diversity, FD, CWM, and soil physicochemical properties. The relative effects of species diversity and soil abiotic features on variation in functional characteristics were then evaluated. We found that different restoration communities altered most community structures and functional properties in terms of species diversity, FD, and CWM. CWM values and FD in different communities presented different distribution patterns depending on certain traits and parameters. Significant correlations between functional traits were found at the species and community scales, suggesting a potential covariation between these selected traits in communities. The results of redundancy analysis and variation partitioning showed that most of the variation in functional characteristics, especially CWM, was explained by soil moisture and available phosphorus, indicating that habitat filters regulate the functional characteristics of plant communities mainly by changing the dominant species composition and functional traits of species. Therefore, the selection of restoration species adapted to low soil moisture and available phosphorus and the construction of communities based on selected species as the dominant species can effectively drive community assembly and ecosystem functions in the vegetation restoration process.

Background: The NAC transcription factor family of genes is one of the largest families of transcription factors in plants, playing important functions in plant growth and development, response to adversity stress, disease resistance, and hormone signaling. In this study, we identified the number of members of the Panax notoginseng NAC (PnNAC) gene family and conducted a comprehensive analysis of their physicochemical characteristics, chromosomal location, evolutionary features, and expression patterns both in different parts of the plant at different growth stages and in response to infection by Alternaria panax. Methods: The NAC gene family in P. notoginseng was identified using Hidden Markov Model (HMMER) and National Center of Biotechnology Information Conserved Domain Database (NCBI CDD), and their physicochemical properties were analyzed with Perl scripts. Phylogenetic relationships were determined using Clustal Omega and FastTree, and gene structures were visualized with an R script. Promoter regions were analyzed with PlantCARE, motifs with MEME and ggmotif, and transcriptome data were processed using Hical Indexing for Spliced Alignment of Transcripts (HISAT2) and HTseq. Results: This study identified 98 PnNAC genes in P. notoginseng, analyzed their characteristics (protein lengths 104–882 aa, molecular weights 11.78–100.20 kDa, isoelectric points 4.12–9.75), location (unevenly distributed on 12 chromosomes, no tandem repeats), evolution, and expression patterns (distinct in different parts, growth stages, and after A. panax infection). Conclusions: PnNAC plays an important role in the growth and development of P. notoginseng and in its response to A. panax. PnNAC could be a candidate gene for further research on and functional analysis of P. notoginseng disease resistance.