Yanghua Yu

Scientific irrigation can not only achieve efficient water resource utilization but also help improve crop yield and quality. To clarify the effects of different irrigation methods on leaf nutrient status and phyllosphere microbial community structure in Zanthoxylum planispinum var. dingtanensis, this study established three treatments—no irrigation (control), sprinkler irrigation, and flood irrigation—in the Huajiang Rocky Desertification Control Experimental Area in Guizhou, and systematically measured leaf total carbon (TC), total nitrogen (TN), total phosphorus (TP), and total potassium (TK) contents. Meanwhile, high-throughput sequencing of bacterial 16S rDNA and fungal ITS was used to analyze phyllosphere microbial community composition and to explore its response to leaf nutrient factors. The results showed that leaf nutrient contents did not differ significantly among irrigation treatments (p > 0.05). Flood irrigation had the lowest TK content and relatively large within-treatment variation, whereas sprinkler irrigation showed relatively low within-treatment variation for all nutrient indices. Bacterial Chao1, Shannon, and Simpson indices did not differ significantly among treatments; the fungal Chao1 index under sprinkler irrigation was significantly lower than under no irrigation and flood irrigation (p < 0.05). The dominant bacterial phyla were Cyanobacteria, Proteobacteria, Actinobacteria, and Bacteroidetes. The relative abundance of Bacteroidetes under sprinkler irrigation was significantly higher than under flood irrigation (p < 0.05); Firmicutes under flood irrigation was significantly higher than under no irrigation and sprinkler irrigation; in addition, Hymenobacter was significantly enriched under sprinkler irrigation. The dominant fungal phyla were Ascomycota and Basidiomycota. Under sprinkler irrigation, the relative abundance of Ascomycota was significantly lower than under no irrigation, whereas the relative abundances of Basidiomycota under sprinkler and flood irrigation were significantly higher than under no irrigation (p < 0.05). In addition, the relative abundance of Alternaria under flood irrigation was significantly higher than that under sprinkler irrigation. Redundancy analysis (RDA) indicated that leaf nutrient indices (TC, TN, and TP) were not significantly correlated with the overall phyllosphere microbial community structure (p > 0.05), whereas TK was one of the potentially important environmental factors influencing the distribution of dominant phyllosphere microbial genera. In summary, different irrigation methods did not significantly alter the leaf nutrient content of Zanthoxylum planispinum var. dingtanensis but significantly reshaped the phyllosphere microbial community structure and specifically increased the relative abundances of Bacteroidetes, Firmicutes, Hymenobacter, and other taxa. This study provides preliminary empirical evidence and data support for understanding the regulatory mechanisms by which irrigation measures affect phyllosphere microecology in the cultivation of Zanthoxylum planispinum var. dingtanensis in rocky desertification areas.

Introduction: Karst rocky desertification is a severe form of land degradation in southwest China, where vegetation restoration has been widely implemented to rebuild soil habitat and biodiversity. However, how restoration‐associated changes in soil conditions correspond to belowground biotic recovery remains poorly understood. Objectives: We compared soil habitat conditions and soil micro‐food web (SMFW) structure across six vegetation restoration systems at the Huajiang Rocky Desertification Control Station to identify habitat attributes and soil biotic indicators associated with belowground recovery. Methods: Soil physicochemical properties, microbial communities, nematode trophic groups, and metabolic footprints were assessed using univariate analyses, exploratory redundancy analysis (RDA), and structural equation modeling (SEM). Results: Restoration systems differed markedly in soil moisture, bulk density, nutrient status, microbial attributes, and nematode trophic organization. Among the measured habitat variables, soil moisture showed the most consistent associations with belowground biotic patterns. Systems with greater moisture retention were generally associated with higher bacterial abundance, larger total nematode populations, greater omnivore‐predator abundance, and more developed food‐web structure, whereas drier and more physically constrained systems were associated with more limited belowground development. Fungal‐fungivore associations were comparatively weak. Exploratory RDA revealed multivariate associations among soil, microbial, and nematode attributes, while SEM indicated that moisture‐associated microbial variation was linked to nematode trophic organization. Conclusions: Belowground recovery across these karst vegetation restoration systems was closely associated with soil habitat conditions, particularly soil moisture. Omnivore‐predators and SMFW metrics showed promise as indicators of restoration‐associated belowground recovery.

Zanthoxylum planispinum var. dingtanensis (hereafter Z. planispinum) is a pioneer plant for the ecological restoration of karst rocky desertification, offering both ecological rehabilitation and economic benefits. Due to the combined pressure from soil degradation and fruit harvesting, nutrient depletion and quality decline have intensified. Therefore, investigating the effects of fertilization on pericarp yield and quality provides the scientific basis for its precise fertilization. This study examined a Z. planispinum plantation subjected to five treatments in 2021: no fertilization (CK); organic fertilizer + chemical fertilizer + sprinkler irrigation (T1); chemical fertilizer + sprinkler irrigation (T2); chemical fertilizer alone (T3); and legume (soybean) intercropping + chemical fertilizer + sprinkler irrigation (T4). It explored the intrinsic relationships between fruit quality and soil physicochemical properties, identified key soil factors, and conducted a comprehensive quality evaluation, providing a scientific basis for precise fertilization in karst regions. The results indicated that (1) whole-fruit water content ranged from 61.30% to 64.37%, showing no significant differences, while variations were observed in the other phenotypic traits. T1 exhibited the highest values for Hydroxy-β-sanshool (2.42 mg·g⁻¹), Hydroxy-ε-sanshool (0.80 mg·g⁻¹), essential oil content (8.57%), and fresh weight per plant (9.9 kg). After long-term soybean intercropping, pericarp thickness reached its maximum (0.45 mm), but the content of aroma compounds decreased significantly. Compared to the other four treatments, the unfertilized control (CK) showed significantly higher values for the pericarp dry weight ratio, proportion of closed-eye peppercorns, and relative content of d-limonene, with increases of 5.5–13.94%, 130.91–568.42%, and 8.74–14.46%, respectively. (2) An inhibitory effect was observed between pericarp numbing compounds and soil calcium/phosphorus levels, while the synthesis of aroma compounds was constrained by the soil C/N ratio. Soil P/K ratio was identified as the dominant factor affecting overall quality. (3) The comprehensive fruit quality index ranked as follows: T1 (1.2933) > T3 (0.666) > T2 (0.5285) > CK (−1.1555) > T4 (−1.2098). Therefore, the T1 treatment is recommended for promotion as the fertilization management practice for Z. planispinum plantations in karst regions.

Karst microhabitats, characterized by their complex structures and unique functions, serve as critical habitats and resource reservoirs for biodiversity. However, systematic research in this area remains limited. This study conducts a systematic literature review based on publications from the China National Knowledge Infrastructure (CNKI) and Web of Science (WOS) databases, with a focus on karst microhabitats in China. The objectives are to synthesize domestic research progress and compare it with international studies to enhance the understanding of microhabitats. The findings reveal that: (i) the number of publications on this topic has generally increased, with CNKI literature predominantly centered on karst and microhabitat entities (47% of the total), whereas WOS publications place greater emphasis on biodiversity within microhabitats (24%); (ii) key advances and landmark findings from studies conducted at different scales in Chinese karst regions are highlighted, along with a summary of critical scientific issues; and (iii) representative techniques applicable to karst microhabitats in China are evaluated, drawing on international research experience and their adaptive outcomes. Moving forward, research on karst microhabitats in China should prioritize quantitative analysis of subsurface spatial characteristics and integrate interdisciplinary approaches to elucidate resource allocation mechanisms.

Zanthoxylum planispinum var. Dingtanensis (hereafter Z. planispinum) has excellent characteristics, including Ca and drought tolerance. It can flourish in stony soils, and it is used as a pioneer plant in karst rocky desertification control. However, soil degradation, coupled with the removal of nutrients absorbed from the soil by Z. planispinum’s fruit harvesting, exacerbates nutrient deficiency. The effects of fertilization on soil nutrient utilization and microbial limiting factors remain unclear. Here, we established a long-term (3 year) field experiment of no fertilization (CK), organic fertilizer + chemical fertilizer + sprinkler irrigation (T1), chemical fertilizer + sprinkler irrigation (T2), chemical fertilizer treatment (T3), and leguminous (soybean) + chemical fertilizer + sprinkler irrigation (T4). Our findings indicate that fertilization significantly improved the nutrient uptake efficiency of Z. planispinum, and it also enhanced urease activity compared with CK. T1 increased soil respiration and improved water transport, and the soil nutrient content retained in T1 was relatively high. It delayed the mineralization rate of organic matter, promoted nutrient balance, and enhanced enzyme activity related to the carbon and nitrogen cycle. T4 caused soil acidification, reducing the activity of peroxidase (POD) and polyphenol oxidase (PPO). The soil microbial community in the Z. planispinum plantation was limited by carbon and phosphorus, and T1 mitigated this limitation. This study indicated that soil nutrient content regulated enzymatic activity by influencing microbial resource limitation, with organic carbon being the dominant factor. Overall, we recommend T1 as the optimal fertilization strategy for Z. planispinum plantations.

Many studies have shown that seed traits, which are among the most important plant traits, can be inherited stably, a finding which is of great value for the improvement of seed germination, seed propagation, seedling establishment, plant breeding, and ecological restoration. The differences in phenotype and nutritional traits and their interactions in Zanthoxylum planispinum var. dingtanensis were ascertained, and the nutrient input rule and the strategy of resource balancing were analyzed in order to provide a scientific basis for the screening of improved variants of the test plant. The nutrient distribution with in the tissues of Z. planispinum var. dingtanensis fruit was that the pericarp had adequate concentrations of N and P concentrations and the seed was also sufficient in P, but low in N concentration. Inorganic nutrients were particularly invested in the pericarp, while organic nutrients are more likely to be stored in the seed. In the economic spectrum of seed traits, the large leaf Zanthoxylum variant represented the low-investment economic type, the tufted leaf Zanthoxylum variant represented the high-investment luxury type, and the safflower Zanthoxylum and acutifoliate leaf Zanthoxylum variants represented transitional types. Inorganic nutrients were more invested in the pericarp to produce secondary metabolites, while organic nutrients are more likely to be stored in the seed to ensure seed germination and seedling establishment in order to achieve inheritance. The variants of Z. planispinum var. dingtanensis differ in terms of resource allocation and balance, which could be further exploited through combining characters in breeding programs.

Social progress and the improvement of living standards are often accompanied by the intensification of ecological crises. The long-term abuse of natural resources has led to the accumulation of ecological liabilities, which in turn seriously hinders economic development. This has prompted all sectors of society to recognize the importance of ecological carrying capacity (ECC) and ecological security (ES). Remarkable progress has been made in karst desertification control (KDC), which has helped reshape the ECC and ES pattern of forests. Currently, the research field of ECC and ES is experiencing rapid development. Further studies in these areas have immeasurable value in promoting regional sustainable development strategies and strengthening ecological civilization construction. The objective of this paper is to provide an overview of the current research status and potential challenges in the field of ECC and ES, with a view to optimizing the program of forest restoration and protection in KDC. This study systematically analyzed 350 relevant studies and found that (1) research on forest ECC and ES has shown a strong growth trend overall, especially after 2017, with a growth rate exceeding 75%; (2) the literature predominantly focuses on the assessment of forest ECC (40.58%) and the enhancement of forest ES (23.42%); and (3) geographically, research findings are heavily concentrated in Asia, representing 95.40% of the total. Notably, China emerges as the primary contributor to research in this field, accounting for a substantial 94.12%. Based on the above analysis, this review summarizes the significant advancements in forest ecosystems, ECC, and ES, while also delving into the key scientific issues that need to be addressed. Furthermore, it offers valuable insights from forest ecosystems in tackling KDC, with the goal of offering guidance and strategic recommendations for future research and practices in managing delicate ecological environments.

Zanthoxylum planispinum is a type of plant with homologous properties in medicine and food, making it well-loved in China. To explore the development of the Z. planispinum field over the past 20 years, its research hotspots and frontier trends were analyzed. This study conducted database-based visualization analyses and knowledge graph analyses using CiteSpace software with data concerning Z. planispinum published in the Chinese National Knowledge Infrastructure and Web of Science databases between 2003 and 2023. Over the last 20 years, the number of Chinese and English publications on Z. planispinum has shown increasing trends. The foci of this research were mainly germplasm resources, cultivation management, seed oil extraction technology, flavonoid extraction technology, and correlation analyses of antioxidant activities. The main research frontiers included the unified standard naming and adaptation mechanisms of Z. germplasm resources, orientation cultivation, functional component extraction, processing technology research and development, and industrial chain construction. The results provide a scientific reference for the high-quality development of the Z. planispinum industry.

Background: Leaf litter is the products of metabolism during the growth and development of plantation, and it is also an important component of nutrient cycling in plantation ecosystems. However, leaf litter chemistry and its effects on soil microorganisms in different ages, as well as the interactions between chemical components in leaf litter have been rarely reported. Based on this, this paper took Zanthoxylum planispinum var. dintanensis (hereafter Z. planispinum) plantations of 5–7, 10–12, 20–22, and 28–32 years old as the objects. By using one-way ANOVA, Pearson correlation analysis and redundancy analysis, we investigated leaf litter chemistry and its effects on soil microorganisms in different ages, and to reveal internal correlation of various chemical components in leaf litter, which can provide a scientific basis for the regulation of soil microbial activity in plantations. Results: The variation of organic carbon with plantation age was more stable compared to total nitrogen and phosphorus of leaf litter. Nitrogen resorption was stronger than phosphorus resorption efficiency in Z. planispinum, and resorption efficiencies of leaf nitrogen and phosphorus for different ages were lower than the global average. Total nitrogen was highly significantly positively correlated with lignin, and total potassium was significantly positively correlated with tannin, suggesting the increase of inorganic substances in leaf litter would promote the accumulation of secondary metabolites. The leaf litter chemical traits explained up to 72% of soil microorganisms, where lignin was positively correlated with fungi and negatively correlated with bacteria, indicating that fungi are able to decompose lower quality litter and can break down complex and stable organic compounds more rapidly than bacteria. The nutrient elements carbon and nitrogen in the leaf litter and their interrelationship also have a great impact on soil microorganisms, because carbon is not only the element that provides energy, but also the element with the largest content in the microbiota. Conclusions: The sustained increase in inorganic nutrients of leaf litter did not favor the decomposition of secondary metabolites, but rather inhibited the degradation of leaf litter. The significant positive effect of the leaf litter chemistry on soil microorganisms indicates the important role of leaf litter in promoting nutrient cycling in Z. planispinum plantations.