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Exploring the elevation distribution characteristics, biomass allocation strategies, and the effects of elevation, soil factors, and functional traits on the biomass of Gentianella turkestanorum (Gand.) Holub is of great significance for the production, development, utilization, and protection of the medicinal material resources. In this study, we investigated the biomass and functional traits of the root, stem, leaf, and flower of G. turkestanorum, analyzing their elevation distribution patterns, allometric growth trajectories, and their correlations. The results showed that the biomass of different organs of G. turkestanorum decreases with increasing elevation, and the belowground biomass/aboveground biomass increases with elevation. The flower biomass accounts for 59.24% of the total biomass, which was significantly higher than that of other organs. G. turkestanorum biomass follows the optimal allocation theory, adopting a 'pioneering' growth strategy at low elevations and a 'conservative' strategy at high elevations. Chlorophyll content and leaf thickness of G. turkestanorum were positively correlated with elevation, but leaf dry matter content and the number of flowers were negatively correlated with elevation. Compared to functional traits, elevation and soil factors have a stronger explanatory power regarding the biomass of G. turkestanorum. Elevation, soil moisture content, pH, available phosphorus, total nitrogen, and ammonium nitrogen significantly affect the biomass of G. turkestanorum, with only pH showing a positive correlation with biomass. Among these factors, elevation, soil moisture content, and pH significantly impact the accurate prediction of G. turkestanorum biomass. The number of flowers, crown width, root length, root diameter, and leaf dry matter content all have a significantly positive correlation with the biomass of G. turkestanorum, with the number of flowers and root diameter making significant contributions to the accurate prediction of biomass. Elevation can directly affect the biomass of G. turkestanorum and can also indirectly affect it through other pathways, with the direct effect being greater than the indirect effect. [ABSTRACT FROM AUTHOR]

Background: Plants rely heavily on the formation of post-embryonic organs, such as leaves, branches, and lateral roots, to adapt to varying soil conditions. Lateral roots (LR) play a crucial role in the plant root system, serving as the primary factor in the exploration of water and nutrients in the soil. The development of LR is meticulously controlled by phytohormones to respond to the information obtained from the surrounding soil. This regulation ensures an optimal arrangement of lateral roots, enabling efficient nutrient absorption and adaptation to the challenging environmental conditions. Scope: This review summarizes recent progress in understanding the mechanisms of lateral root layout in different soil micro-environments and the role of phytohormones in mediating LR development for soil adaptation. Conclusions: The intricate signaling network governing LR layout involves interactions among various soil factors, which are mediated by phytohormones. Despite its complexity, recent studies have yielded significant insights that can be applied to optimize LR arrangement in soil profiles through genetic and cultivation methods to enhance crop yield and stress tolerance. [ABSTRACT FROM AUTHOR]

The Italian seismic code provides a simplified approach to account for the effect of local seismostratigraphical configuration on the expected ground motion. This approach, common with other seismic codes, provides specific 'soil factors' as a function of a set of reference subsoil conditions (soil classes): these factors are considered in 1D subsoil configurations to modify the uniform probability hazard spectrum deduced from probabilistic seismic hazard at reference soil conditions. It is inferred that, to provide a coherent management of uncertainty affecting the response spectrum to be used for the design, the contribution of uncertainty affecting soil factors must be carefully considered to avoid biases in the hazard evaluation. In the present study, variability of soil factors representative of each soil class has been explored by numerical simulation relative to many seismostratigraphical configurations inferred from seismic microzonation studies available in Italy relative to 1689 municipalities. This analysis shows that variability of soil factors is of the same order of magnitude of variability affecting reference response spectra, which implies that the former cannot be neglected as presently happens in the common practice. It is also shown that neglecting this contribution can lead to underestimate the impact of subsoil configuration on the regularized response spectrum provided by the norm, in particular, in the short period range. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to human activities and severe climatic conditions, the population of Ammodendron bifolium, an excellent sand-fixing plant, has gradually decreased in the Takeermohuer Desert. The plant-associated bacteria community can enhance its survival in harsh environments. However, the understanding of A. bifolium-associated bacterial community is still unclear during the harsh winter. We investigated the bacterial community structure from the A. bifolium rhizosphere and nonrhizosphere at different depths (i.e., 0–40 cm, 40–80 cm, 80–120 cm) and from endosphere (i.e., root endosphere and stem endosphere) in winter. At the same time, we analyzed the impact of different compartments and soil factors on the bacterial community structure. Studies have shown that the A. bifolium rhizosphere exhibits higher levels of SOM (soil organic matter), SOC (soil organic carbon), SAN (soil alkaline nitrogen), and SAK (soil available potassium) compared with the nonrhizosphere. The dominant bacterial phyla were Proteobacteria (19.6%), Cyanobacteria (15.9%), Actinobacteria (13.6%), Acidobacteria (9.0%), and Planctomycetota (5.7%) in the desert. Proteobacteria (24.0–30.2%) had the highest relative abundance in rhizosphere, Actinobacteria (18.3–22.6%) had the highest relative abundance in nonrhizosphere, and Cyanobacteria had the highest relative abundance in endosphere. At the genus level, the relative abundance of Pseudomonas (1.2%) in the root endosphere was the highest and the other genera were mostly unclassified. The Chao1 and PD_whole_tree indices showed that the diversity of the bacterial communities decreased from nonrhizosphere, rhizosphere, root endosphere to stem endosphere. Co-occurrence network analyses identified Proteobacteria and Actinobacteria as key species across the three compartments. Additionally, unique keystone species like Cyanobacteria, Verrucomicrobiota, and Desulfobacterota were found only in the endosphere. The bacterial community in the rhizosphere was influenced by factors such as EC (electrical conductivity), STC (soil total carbon), SOM, SOC, STN (soil total nitrogen), SAN, STP (soil total phosphorus), and SAK, while that of the nonrhizosphere was mainly influenced by pH, C/N (STC/STN), SAP, and distance. The study highlighted differences in bacterial community composition, diversity, and influencing factors across the three compartments, which can provide a better understanding of the association/interactions between A. bifolium and bacterial communities and lay a foundation for revealing its adaptability in winter. [ABSTRACT FROM AUTHOR]

Most research on carbon storage in forests has focused on qualitative studies of carbon storage and influencing factors rather than on quantifying the effect of the spatial distribution of carbon storage and of its influencing factors at different scales. Here we described the spatial distribution of aboveground carbon storage (ACS) in a 20-ha plot in a subtropical evergreen broad-leaved forest to evaluate and quantify the relative effects of biotic factors (species diversity and structural diversity) and abiotic factors (soil and topographic factors) on ACS at different scales. Scale effects of the spatial distribution of ACS were significant, with higher variability at smaller scales, but less at larger scales. The distribution was also spatially heterogeneous, with more carbon storage on north- and east-facing slopes than on south- and west-facing slopes. At a smaller scale, species diversity and structural diversity each had a direct positive impact on ACS, but soil factors had no significant direct impact. At increasing scales, topographic and soil factors gradually had a greater direct influence, whereas the influence of species diversity gradually decreased. Structural diversity had the greatest impact, followed by topographic factors and soil factors, while species diversity had a relatively smaller impact. These findings suggest studies on ACS in subtropical evergreen broadleaf forests in southern China should consider scale effects, specifically on the heterogeneity of ACS distribution at small scales. Studies and conservation efforts need to focus on smaller habitat types with particular emphasis on habitat factors such as aspect and soil conditions, which have significant influences on community species diversity, structural diversity, and ACS distribution. [ABSTRACT FROM AUTHOR]

To clarify the degree of coupling and coordination between herbaceous plant community diversity and soil factors after slope vegetation restoration, the understory herbaceous plant communities and soils of 18 typical slope vegetation greening models in Yan’an New District were used as research objects. Five 1 m× 1 m sample plots were set up in each model and the physical and chemical properties of the soil in the sample plots were measured. The gray correlation method was used to construct a vegetation-soil coupling model to evaluate the coupling relationship between herbaceous plant diversity and soil factors after slope vegetation restoration. The results showed that there were 22 species of herbaceous plants, belonging to 12 families, on the slopes of Yan’an New District. Among them,the families Asteraceae and Poaceae were the most abundant, both accounting for 22. 73% of total species number. The degree of feedback of the herbaceous plant community diversity indices to the soil was in the order of Shannon-Wiener＞ Margalef＞ Simpson＞ Pielou indices. The correlation between the herbaceous plant community diversity and soil factors in the study area was moderate or above, of which the correlation coefficient of soil electrical conductivity, which was more closely related to community diversity, was 0. 852. Overall, the performance of the coupling relationship between herbaceous plant diversity and soils after slope vegetation restoration in Yan’an New District was good, and 66. 67% of existing greening models have already crossed the stage of incongruity in this coupling relationship. However, the understory of herbaceous plant communities and soil systems are yet to reach the optimal coordination level. [ABSTRACT FROM AUTHOR]

Soil nematodes are the most abundant soil metazoans, occupying multiple trophic levels in the soil food web and playing an important role in soil function. Research on the biogeographic distribution patterns of soil nematode communities and their drivers has received greater attention. However, the distribution characteristics of soil nematode communities along the elevational gradient in the arid and semi-arid regions of Northwest China remain unclear. In this study, four elevational gradients (1750–1900, 1900–2100, 2100–2350 and 2350–2560 m) were established on Luoshan Mountain, Ningxia, an arid and semi-arid region in Northwest China, and soil nematodes in the soil layers of 0–10, 10–20 and 20–40 cm were investigated using the improved Baermann funnel method. The results revealed a monotonically decreasing trend in the total number of soil nematodes along the elevational gradient and soil layer depth, decreasing by 63.32% to 79.94% and 73.59% to 86.90%, respectively, while the interactions were not obvious. A total of 1487 soil nematodes belonging to 27 families and 32 genera were identified across the elevational gradient, with Helicotylenchus as the dominant genus, accounting for 10.43% of the total number of nematodes, and bacterivore nematodes as the main trophic groups, accounting for 32.39% to 52.55% of the relative abundance at each elevation, which increased with increasing elevation. Soil nematode community diversity, richness and maturity indices were relatively low at high elevation and decreased by 44.62%, 48% and 54.74%, respectively, with increasing soil layer depth at high elevations. Compared to low elevations, high-elevation soils experienced greater disturbance, reduced structural complexity and nutrient enrichment of the soil food web, and a shift in soil organic matter decomposition from bacterial to fungal pathways as elevation increased. Finally, redundancy analysis showed that soil pH, bulk density, soil moisture, soil organic carbon, available nitrogen, available phosphorus and available potassium were the main soil factors affecting the composition of soil nematode communities, which well explained the differences in nematode communities at different elevations and soil depths. This study can be used as basic information for further research on soil biota in this mountainous region, expanding our further understanding of the spatial ecology of soil nematodes in the arid and semi-arid mountain ecosystems. [ABSTRACT FROM AUTHOR]

This study explores the environmental changes in the disturbed area of coal mining and presents the driving factors of ecological self-restoration. Specifically, we measured the soil nutrient and soil enzyme indicators in the mining area and non-mining area from 2014 to 2017 and 2019, and evaluated the stoichiometric characteristics of soil carbon (C), nitrogen (N), and phosphorus (P). The experimental results show that the total phosphorus concentration gradually recovered with the increase of mining years, while organic matter, available potassium, and urease first increased and then decreased with the increase of mining years. There were significant differences in total phosphorus, C/N ratio, N/P ratio, and C/P ratio between the working face and the subsidence disturbance zone. Random forest analysis showed that soil sucrase, urease, available potassium, total nitrogen, total phosphorus, C/P ratio, C/N ratio, and water-soluble salts were the key factors influencing soil nutrient cycling in different time periods; while C/N ratio, N/P ratio, total phosphorus, alkaline phosphatase, and water-soluble salts were the key factors influencing soil nutrient cycling at different locations. Mining years of the working face has differing influence path on soil factors and soil enzymes. This study could provide theoretical proof for the artificial guided self-restoration plan in coal mining subsidence areas and for ecological restoration in western mining areas.

Soil nematodes are the most abundant soil metazoans, occupying multiple trophic levels in the soil food web and playing an important role in soil function. Research on the biogeographic distribution patterns of soil nematode communities and their drivers has received greater attention. However, the distribution characteristics of soil nematode communities along the elevational gradient in the arid and semi-arid regions of Northwest China remain unclear. In this study, four elevational gradients (1750-1900, 1900-2100, 2100-2350 and 2350-2560 m) were established on Luoshan Mountain, Ningxia, an arid and semi-arid region in Northwest China, and soil nematodes in the soil layers of 0-10, 10-20 and 20-40 cm were investigated using the improved Baermann funnel method. The results revealed a monotonically decreasing trend in the total number of soil nematodes along the elevational gradient and soil layer depth, decreasing by 63.32% to 79.94% and 73.59% to 86.90%, respectively, while the interactions were not obvious. A total of 1487 soil nematodes belonging to 27 families and 32 genera were identified across the elevational gradient, with Helicotylenchus as the dominant genus, accounting for 10.43% of the total number of nematodes, and bacterivore nematodes as the main trophic groups, accounting for 32.39% to 52.55% of the relative abundance at each elevation, which increased with increasing elevation. Soil nematode community diversity, richness and maturity indices were relatively low at high elevation and decreased by 44.62%, 48% and 54.74%, respectively, with increasing soil layer depth at high elevations. Compared to low elevations, high-elevation soils experienced greater disturbance, reduced structural complexity and nutrient enrichment of the soil food web, and a shift in soil organic matter decomposition from bacterial to fungal pathways as elevation increased. Finally, redundancy analysis showed that soil pH, bulk density, soil moisture, soil organic carbon, available nitrogen, available phosphorus and available potassium were the main soil factors affecting the composition of soil nematode communities, which well explained the differences in nematode communities at different elevations and soil depths. This study can be used as basic information for further research on soil biota in this mountainous region, expanding our further understanding of the spatial ecology of soil nematodes in the arid and semi-arid mountain ecosystems. [ABSTRACT FROM AUTHOR]

The organic carbon sequestered by the world's mangrove forests plays a key role in the global carbon cycle and may be central to climate change mitigation. This is because mangroves typically exhibit high rates of net primary production and greater carbon sequestration capacity compared to terrestrial ecosystems. This study investigated the influence of selected soil physicochemical properties on the soil organic carbon (SOC) content of Rekawa mangrove forest, Sri Lanka. The effect of soil pH, salinity, conductivity, moisture content (%), bulk density, porosity, phosphate, and nitrate content on SOC was examined along an intertidal gradient. Results showed, SOC was positively correlated with salinity (r2= 0.74), conductivity (r2= 0.76), moisture content (r2= 0.76), porosity (r2= 0.92), and phosphate content (r2= 0.74) while SOC was negatively correlated with bulk density (r2= -0.92) across the entire intertidal zone. Generalised Linear Model (GLM) resolved SOC to be best predicted as a function of soil porosity and soil moisture content [Akaike Information Criterion (AIC): 142.04], with other soil properties modulating the results within some zones. Overall, the present study shows that specific consideration of soil physicochemical properties could allow improved estimates of total carbon stocks which are becoming increasingly important for carbon accounting and national inventories. [ABSTRACT FROM AUTHOR]

Plant aboveground biomass reflects the resilience of ecosystem productivity to different environmental factors and plays an important role in biodiversity and ecosystem carbon cycles. Although many studies have investigated the relationship between aboveground biomass and species diversity, stand structural diversity is an important factor affecting ecosystem function. The mechanism of how climate and soil factors affect aboveground biomass through species diversity and structural diversity remains unclear. Here, combing data from 8 locations of Abies fargesii var. faxoniana primary forest, a structural equation model was used to study the effects of climate factors, soil factors, species diversity, and structural diversity on aboveground biomass. Our results demonstrated that climate factors affect aboveground biomass mainly through the indirect effect of species diversity. Species diversity indirectly affects aboveground biomass through its effects on structural diversity. Both direct effects of soil factors and indirect effects through structural diversity can significantly affect aboveground biomass. Therefore, maintaining higher diversity of stand structure and soil nutrients can improve aboveground biomass, and thus better improve ecosystem functions such as carbon storage. [ABSTRACT FROM AUTHOR]

Houseplant cultivation has become increasingly popular, allowing individuals to bring nature into their homes. However, successful indoor gardening requires careful monitoring of soil parameters to ensure optimal plant growth. To address this need, sensor technology and Internet of Things (IoT) devices are utilized to monitor soil temperature and moisture levels, which play crucial roles in plant growth. Various soil factors are sensed and collected using an IoT-based microcontroller, with data transmission facilitated by a Message Queue Telemetry Transport (MQTT) broker. Visualization of the data is achieved through the Node-RED programming tool, simplifying dashboard creation for easy monitoring. Furthermore, the collected data is stored in a MySQL server, enabling further analysis through SQL queries. The day is divided into four quarters with six-hour intervals, allowing for soil data collection using temperature and moisture sensors. The resulting information on the dashboard facilitates informed decision-making to enhance soil conditions for optimal indoor plant growth. Experimentation has revealed a reduction in soil temperature of 3°C during daytime due to air conditioning operation, while soil moisture content remains consistently between 60 to 65% during early mornings and late evenings. Additionally, emphasis is placed on remote management using IoT systems, enabling monitoring of plant growth even when access is limited. Overall, monitoring soil factors using IoT technology offers a promising approach to optimizing indoor gardening practices and minimizing environmental resource consumption. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Northwest A & F University - Natural Science Edition is the property of Editorial Department of Journal of Northwest A&F University (Natural Science Edition) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study explores the impact of stumping intervals on the stability of artificial Salix psammophila forests in Hangjin Banner, Ordos City, China. We compared S. psammophila (Salix psammophila) forests with stumping intervals of 1, 2, and 3 years to those with non-stumping intervals of 5 + years. Stumping positively affects S. psammophila regeneration, with growth indicators improving with longer intervals. Herbaceous diversity and biomass increase post-stumping, peaking at 3-year intervals. Soil erosion occurs immediately after stumping, but the soil gradually stabilizes. Stumping also affects soil water storage, with moisture content increasing as the S. psammophila grows. Soil nutrient accumulation is impacted, with available phosphorus, organic matter, total carbon, and alkaline nitrogen peaking at 3-year stumping intervals. [ABSTRACT FROM AUTHOR]

Copyright of South China Fisheries Science is the property of South China Fisheries Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Listeria spp. are widely distributed environmental bacteria associated with human foodborne illness. The ability to detect and characterize Listeria strains in the natural environment will contribute to improved understanding of transmission routes of contamination. The current standard for surveillance and outbreak source attribution is whole-genome sequencing (WGS) of Listeria monocytogenes clinical isolates. Recently, metagenomic sequencing has also been explored as a tool for the detection of Listeria spp. in environmental samples. This study evaluated soil samples from four locations across altitudes ranging from 1,500 to 4,500 ft in the Nantahala National Forest in North Carolina, USA. Forty-two Listeria isolates were cultured and sequenced, and 12 metagenomes of soil bacterial communities were generated. These isolates comprised 14 distinct strains from five species, including Listeria cossartiae subsp. cayugensis (n = 8; n represents the number of distinct strains), L. monocytogenes (n = 3), “Listeria swaminathanii” (Lsw) (n = 1), Listeria marthii (n = 1), and Listeria booriae (n = 1). Most strains (n = 13) were isolated from lower altitudes (1,500 or 2,500 ft), while the L. swaminathanii strain was isolated from both higher (4,500 ft) and lower (1,500 ft) altitudes. Metagenomic analysis of soil described a reduction in both bacterial community diversity and relative abundance of Listeria spp. as the altitude increased. Soil pH and cation exchange capacity were positively correlated (P < 0.05) with the abundance of Listeria spp. as detected by metagenomics. By integrating culture-independent metagenomics with culture-based WGS, this study advances current knowledge regarding distribution of Listeria spp. in the natural environment and suggests the potential for future use of culture-independent methods in tracking the transmission of foodborne pathogens.IMPORTANCEAs a foodborne pathogen, Listeria continues to cause numerous illnesses in humans and animals. Studying the diversity and distribution of Listeria in soil is crucial for understanding potential sources of contamination and developing effective strategies to prevent foodborne outbreaks of listeriosis. Additionally, examining the ecological niches and survival mechanisms of Listeria in natural habitats provides insights into its persistence and adaptability, informing risk assessments and public health interventions. This research contributes to a broader understanding of microbial ecology and the factors influencing foodborne pathogen emergence, ultimately enhancing food safety and protecting public health. Moreover, using a metagenomic approach provides a detailed understanding of the soil microbial ecosystems, leading to more effective monitoring and control of foodborne pathogens. This study also highlights the potential for integrating metagenomics into routine surveillance systems for food safety in the near future.

Introduction: Considering the effect of physical and chemical factors of soil and climatic factors of temperature and precipitation on the quantity and quality of plant essential oils, a study was conducted with the aim of evaluating the effect of climatic and soil factors on the phytochemistry of the medicinal species of Stachys lavandulifolia in Kalakuh of Amol rangeland and comparing it in two northern and southern aspects. Methods: First, random sampling was done in three selected spots with three repetitions from two aspects. Soil samples were taken from a depth of 0-30 cm and transferred to the laboratory. The essential oils of plants were also extracted by water distillation and their composition was identified by GC/MS. In the statistical section, independent t-test was used to compare compounds in the two northern and southern aspects, and Pearson's correlation analysis was used to analyze the relationships between the data. Results: The results showed that among the extracted compounds, the compound α-Pinene, β-phellandrene, Thymol, Limonene, α-fenchene, γ-cadinene, cis-sabinene hydrate, 1-8-Cineole and Sabinene accounted for the largest percentage. Also, the comparison of the average yield of essential oil in the two aspects showed that the southern aspect has significantly higher average than the northern aspect. The correlation results also indicated that the index factors of soil grain stability, acidity and silt have a very strong correlation at the five percent level. Conclusion: In general, the present results indicate that the compounds extracted from essential oil of Stachys lavandulifolia plant are strongly influenced by the habitat conditions of the region. [ABSTRACT FROM AUTHOR]

Questions: Stomata can reflect the plant's adaptation to environmental changes. However, the variation patterns of stomatal traits across different habitats and their relationships with environmental drivers are still poorly understood. Here, we assessed the extent of interspecific and intraspecific variation in stomatal traits in two typical riparian forests, and investigated how stomatal traits adapt to habitat change as well as trait–environment relationships. Location: The Irtysh River Basin in China. Methods: We measured the stomatal density (SD), stomatal size (SS), and stomatal relative area (SRA) of dominant plant species from two riparian forests: (1) a riparian forest in the valley and (2) a riparian forest in the pediment plain. We analyzed the stomatal trait variation patterns of dominant plant species in different habitats. We then quantified the magnitude of intraspecific and interspecific stomatal trait variability and evaluated the relationships between stomatal traits and environmental factors. Results: We found that SD and SRA were significantly higher in pediment plain forests than in valley forests, whereas SS was not significantly different between these habitats. The SD and SRA of trees in pediment plain forests were significantly higher than those in valley forests, whereas there were no significant differences in understory plants between habitats. The interspecific variation in each stomatal trait was significantly higher than the intraspecific variation. Stomatal traits were more related to the soil environment than to climatic factors. Conclusions: Response strategies of stomatal traits to habitat changes differed between species and functional groups, and trait–environment relationships depended on the habitat type of the riparian forest. Our analysis of stomata trait variation implies adaptive strategies in species of natural riparian forest. Insights into trait–environment relationships could be used to predict carbon and water cycling, and vegetation changes in riparian forests of arid regions, especially in the context of climate change. [ABSTRACT FROM AUTHOR]

The ecologically fragile agro-pastoral ecotone in northern China is characterized by relatively poor arable land quality. Yunzhou District in Datong City, which is situated within this transitional zone, boasts over 600 years of Hemerocallis citrina Baroni cultivation. Exploring the effects of soil physicochemical properties on daylily yield and related agronomic traits is essential for enhancing the ecological and economic value of dominant crops in ecologically fragile areas. Therefore, in this study, we focused on the daylily, a characteristic cash crop that is grown in the agro-pastoral ecotone in Yunzhou District. Physicochemical property measurement and yield estimation were performed using soil samples collected from 37 sites, with Spearman's correlation analysis, one-way analysis of variance with multiple comparisons, path analysis, and stepwise regression analysis used to analyze the generated data. The results showed the following: (1) The pathway analysis of daylily yield with each agronomic trait showed that the BN and PH directly affected the yield of daylily with direct pathway coefficients of 0.844 and 0.7, respectively, whereas the SN indirectly affected the yield of daylily through the BD and PH, with indirect pathway coefficients of 0.827 and 0.566, respectively. (2) A total of four principal components were extracted for the soil factors, of which SMC, ST and BD had large loadings on PC1; OM, TN and pH had large loadings on PC2; AK had large loadings on PC3; and AP had large loadings on PC4. (3) From the principal component regression and stepwise regression, it can be seen that SMC is the most critical factor affecting the yield of daylily, as well as the related agronomic traits, and the results also show that yield prediction was affected by OM, ST, and AK, while BN was influenced by OM and ST, and SN and PH were influenced by AP. Comparing the goodness of fit and significance of the two models, it can be concluded that the stepwise regression model is the optimal model for this study. [ABSTRACT FROM AUTHOR]

Leaf anatomical traits are susceptible to environmental changes and can reflect plant adaptation strategies to the environment. Populus euphratica plays a key role in maintaining ecosystem processes and functions in arid zones, but the variations in leaf anatomical traits of Populus euphratica and their drivers at large scales remain unclear. Here, we investigated 10 leaf anatomical traits of Populus euphratica from 12 sampling sites in the arid zone of China, and explored how they were affected by geographic, climatic, and soil factors. Our results showed that these traits differed significantly between sites (P < 0.05), which was mainly determined by climate and soil factors that together explained 41.4 % of the trait variation. The impact of climate factors is the most critical, as they can directly influence the variation in leaf anatomical traits and indirectly affect trait variation by influencing soil factors. Among them, the max temperature of the warmest month (BIO5), soil available phosphorus (SAP) and soil moisture content (SM) had the most critical effect. Besides, temperature was the major influencing factor for the ratio of spongy tissue thickness to leaf thickness (SR), palisade tissue thickness (PT), the ratio of palisade tissue thickness to spongy tissue thickness (PSR), and the ratio of palisade tissue thickness to leaf thickness (CTR), while soil nutrient was the major influencing factor for leaf thickness (LT), lower epidermis thickness (LET), and spongy tissue thickness (ST). Our results provide important insights into the response of dryland forests to climate change, and suggest that climate warming and declining soil quality may have a stronger effect on Populus euphratica.

China’s agricultural production suffers significant constraints due to low water productivity (WP) and partial factor productivity for nitrogen (PFPN). The pivotal solution to enhance maize yield, WP, and PFPN is through optimizing field management practices. However, previous studies primarily focused on the effects of individual or coupled field management practices on maize yield, WP, or PFPN in an area or land mass, so it is necessary to conduct a comprehensive quantitative analysis of various field management practices on maize yield, WP, and PFPN at the national scale. In this study, we compiled 286 studies encompassing 6959 pairs of experimental data spanning from 1990 to 2023. Meta-analysis was conducted to observe the variations in maize yield, WP, and PFPN across diverse field management practices (straw returning, nitrogen fertilizer application, irrigation practice, and tillage practice) on a national scale. The results showed that nitrogen fertilizer application (215 kg N ha−1) was the most effective in enhancing maize yield and WP by 68.1 % and 54.8 %, respectively. Additionally, irrigation had the most substantial impact on PFPN, enhancing 16.8 %. Straw mulching, application of slow and controlled release fertilizers, drip irrigation, and subsoiling were identified as the most effective practices in increasing maize yield, WP, and PFPN by Random forest model. Maize straw returning could reduce nitrogen fertilizer application by 20 kg ha−1, while increasing WP and PFPN by 4.2 % and 11.6 %, respectively. Moreover, straw returning could reduce water consumption by 23–60 mm, while increasing WP and PFPN by 2.9 % and 6.8 %, respectively. These findings can provide a reference for the formulation of comprehensive management strategies for sustainable maize production in China and globally.

Abstract Plant community assembly is the outcome of long-term evolutionary events (evident as taxonomic diversity; TD) and immediate adaptive fitness (functional diversity; FD); a balance expected to shift in favour of FD in ‘harsh’ habitats under intense selection pressures. We compared TD and FD responses along climatic and edaphic gradients for communities of two species (Dianthus pseudocrinitus and D. polylepis) endemic to the montane steppes of the Khorassan-Kopet Dagh floristic province, NE Iran. 75 plots at 15 sites were used to relate TD and FD to environmental gradients. In general, greater TD was associated with variation in soil factors (potassium, lime, organic matter contents), whereas FD was constrained by aridity (drought adaptation). Crucially, even plant communities hosting different subspecies of D. polylepis responded differently to aridity: D. polylepis subsp. binaludensis communities included a variety of broadly stress-tolerant taxa with no clear environmental response, but TD of D. polylepis subsp. polylepis communities was directly related to precipitation, with consistently low FD reflecting a few highly specialized stress-tolerators. Integrating taxonomic and functional diversity metrics is essential to understand the communities hosting even extremely closely related taxa, which respond idiosyncratically to climate and soil gradients.

Exploring the elevation distribution characteristics, biomass allocation strategies, and the effects of elevation, soil factors, and functional traits on the biomass of Gentianella turkestanorum (Gand.) Holub is of great significance for the production, development, utilization, and protection of the medicinal material resources. In this study, we investigated the biomass and functional traits of the root, stem, leaf, and flower of G. turkestanorum, analyzing their elevation distribution patterns, allometric growth trajectories, and their correlations. The results showed that the biomass of different organs of G. turkestanorum decreases with increasing elevation, and the belowground biomass/aboveground biomass increases with elevation. The flower biomass accounts for 59.24% of the total biomass, which was significantly higher than that of other organs. G. turkestanorum biomass follows the optimal allocation theory, adopting a ‘pioneering’ growth strategy at low elevations and a ‘conservative’ strategy at high elevations. Chlorophyll content and leaf thickness of G. turkestanorum were positively correlated with elevation, but leaf dry matter content and the number of flowers were negatively correlated with elevation. Compared to functional traits, elevation and soil factors have a stronger explanatory power regarding the biomass of G. turkestanorum. Elevation, soil moisture content, pH, available phosphorus, total nitrogen, and ammonium nitrogen significantly affect the biomass of G. turkestanorum, with only pH showing a positive correlation with biomass. Among these factors, elevation, soil moisture content, and pH significantly impact the accurate prediction of G. turkestanorum biomass. The number of flowers, crown width, root length, root diameter, and leaf dry matter content all have a significantly positive correlation with the biomass of G. turkestanorum, with the number of flowers and root diameter making significant contributions to the accurate prediction of biomass. Elevation can directly affect the biomass of G. turkestanorum and can also indirectly affect it through other pathways, with the direct effect being greater than the indirect effect.

The optical saturation problem is one of the main factors causing uncertainty in aboveground biomass (AGB) estimations using optical remote sensing data. It is critical for the improvement in AGB estimation accuracy to clarify the relationships between environmental factors and the variations in optical saturation values (OSVs). In this study, we obtained the OSVs for 20 districts and clarified the individual, interactive, and comprehensive effects of climate, soil, and topographical factors on the OSV variations. The results are as follows: (1) the range of the OSVs was from 104 t/hm2 to 182 t/hm2 for the 20 districts; (2) the soil factor had the greatest (−0.635) influence on the OSVs compared to climate and topography; (3) the highest interaction effect (−0.833) was between climate and soil; (4) the comprehensive effect of the three environmental factors on the OSVs was obvious, and the correlation coefficient was 0.436. Moreover, the mean temperature of the coldest quarter (MCQMean) had the highest effect on the OSVs. The results indicate that environmental factors significantly affect the variation in OSVs through their individual, interactive, and comprehensive effects. Our findings provide a valuable reference for reducing the uncertainty caused by spectral saturation in AGB estimations using optical remote sensing data. [ABSTRACT FROM AUTHOR]

Generating a DNA profile using autosomal Short Tandem Repeat (STR) DNA allele from skeletal remains is a crucial step in the identification process for mass disaster and unidentified person situations. The capacity to extract substantial amounts of relevant DNA from bones, which were highly durable biological components that can withstand soil elements and climatic conditions over long periods of time, would be advantageous. 70 femur male bone samples were collected from two different environmental mass graves (Al-Mahaweel massgrave) in Babil governorate and (Al-Saqlawiya massgrave) in Al-Anbar governorate in Iraq. The DNA from bone samples extracts were assessed by capillary electrophoresis and a standardized set of short tandem repeat (STR) loci are analyzed using Mutiplex 21 STR loci System to allow human identification by matching the profile of the dead individuals with their relatives. From these two different sites; soil samples were collected to analyze and study the different environmental factors and find a relation between the degree of preservation or degradation with these factors like temperature, humidity, salinity, PH and texture of soil and find how these factors can affect on pattern of degradation of DNA profiles. The average of the percentage of the detected alleles in each locus in the two sites; were 87% for Al-Mahaweel site and 32% for Al-Saqlawiya site. we found that clay soil, low salt concentration, PH slightly alkaline and low humidity for Al-Mahaweel site; all participate in DNA preservation while the chalky and very high salt concentration of Al-Saqlawiya site soil; all participate in DNA degradation. Predicting the effect of these factors on the quality of the DNA profiles can be helpful in finding better solutions for many complications that may face the process of analyzing samples and finding sufficient informative profiles. [ABSTRACT FROM AUTHOR]

Plant community assembly is the outcome of long-term evolutionary events (evident as taxonomic diversity; TD) and immediate adaptive fitness (functional diversity; FD); a balance expected to shift in favour of FD in 'harsh' habitats under intense selection pressures. We compared TD and FD responses along climatic and edaphic gradients for communities of two species (Dianthus pseudocrinitus and D. polylepis) endemic to the montane steppes of the Khorassan-Kopet Dagh floristic province, NE Iran. 75 plots at 15 sites were used to relate TD and FD to environmental gradients. In general, greater TD was associated with variation in soil factors (potassium, lime, organic matter contents), whereas FD was constrained by aridity (drought adaptation). Crucially, even plant communities hosting different subspecies of D. polylepis responded differently to aridity: D. polylepis subsp. binaludensis communities included a variety of broadly stress-tolerant taxa with no clear environmental response, but TD of D. polylepis subsp. polylepis communities was directly related to precipitation, with consistently low FD reflecting a few highly specialized stress-tolerators. Integrating taxonomic and functional diversity metrics is essential to understand the communities hosting even extremely closely related taxa, which respond idiosyncratically to climate and soil gradients. [ABSTRACT FROM AUTHOR]

Understanding developments in the trunk sap flow of prevalent tree species within the hilly areas of the Haihe River basin is imperative for ecosystem conservation. Nevertheless, the changes in sap flow of local trees and their response to environmental factors remain elusive. This study focuses on seven dominant tree species in the hilly area of the Haihe River basin and analyzed the relationship between tree sap flow rate and environmental factors at different time scales (hourly and daily). Our findings suggested: (1) Regardless of the time scale, total solar irradiance played a primary role in influencing sap flow rate. Conversely, as the time scale grew, the associations between most soil factors and sap flow rate enhanced, while those with meteorological factors declined. Notably, soil temperature exerted a more profound influence on sap flow rate than soil moisture and conductivity. (2) At the hourly scale, the sap flow rate of each species had a lag effect of 1–2 h with vapour pressure deficit, relative humidity and temperature, and 1 h or no lag effect with total solar irradiance and wind speed. (3) The response model of sap flow rate and environmental factors showed that, except for Pinus tabuliformis Carr., other tree species fit well at various time scales (R2 ≥ 0.59). As the time scale of most tree species increased from hourly scale to daily scale, the fit gradually weakened. Concurrently, considering the time-lag effect, the accuracy of the model has been improved, and the fitting accuracy of Koelreuteria paniculata Laxm. and Pinus tabuliformis Carr. has been significantly improved. [ABSTRACT FROM AUTHOR]

Leaf and root are the most sensitive organs to environment, exploring the relationship between root and leaf functional traits and their responses to environmental factors is helpful to reveal the utilization of resources by plants and their adaption trategies to environment. In order to explore the adaptive strategies of coastal plants, the sandy coastal herbaceous plants in Pingtan Island were taken as the research objects. Three distance gradients were set up from sea and land. Six leaf function traits, leaf thickness, individual leaf area, leaf dry matter content, specific leaf area, leaf tissue density, leaf phosphorus content, and five fine root function traits, root average diameter, root tissue density, specific root length, specific root area, root phosphorus content, were measured to analyze the function traits of leaf and root of coastal plants and their responses to soil factors. The results were as follows: (1) The variation coefficient amplitude of root and leaf function traits in intertidal zone was the smallest, and it was the largest on the gradient 30-60 m away from the high tide line. The individual leaf area, leaf phosphorus content, root average diameter, root tissue density, and root phosphorus content increased with the distance from sea to land; the leaf dry matter content, leaf tissue density, specific root length and specific root area decreased. (2) Plants balanced resource allocation between growth and defense through trait combinations, which showed that there were different degrees of correlation among leaf traits, root traits and root-leaf traits. Among the aboveground and underground corresponding traits, leaf thickness-root average diameter, leaf-root phosphorus content were significantly positively correlated. Specific leaf area with specific root length, specific root area, leaf tissue density-root tissue density had no significant correlation. (3) The interpretation degree of soil factors to the changes of coastal plant functional properties was 52.05%, of which the soil salt content had the greatest impact, followed by soil water content, soil electrical conductivity and soil pH value. In conclusion, in the harsh coastal environment, the soil salt content, soil electrical conductivity, soil water content and soil pH value decrease gradually from sea to land, and the overall environment is low in phosphorus and high in salinity. The plants have shown different survival strategies: the plants closer to the sea adopted the strategy of leaf resource conservation type and root resource acquisition type; the plants farther away from the sea, the strategy of leaf resource acquisition type and root resource conservation type is adopted. The results of this study provide a certain reference value for understanding the response mechanism and adaptability of coastal herbs to environmental gradient changes, which is conducive to the analysis of soil and other environmental characteristics to screen and plant suitable species according to gradient, and promote the restoration and protection of coastal plants.

Desertification has a significant impact on the Zoige meadow. Research efforts are directed towards the rehabilitation of the Zoige desertified alpine meadow, specifically in understanding the soil's physical and chemical characteristics and the functional groupings of plants. However, the relationships between plant functional groups and soil properties remains uncertain. The primary objective of this study is to investigate the correlation between plant functional groups and soil nutrients across various stages of restoration. This study examined important value of plant functional groups, as well as variations in several soil characteristics, such as soil total nitrogen, total carbon, total phosphorus, available nitrogen, available potassium, available phosphorus, and soil pH during the stages of recovery. The results showed that the relative significance of importance values differed across distinct functional groups during different stages of recovery. The important value of legumes was found to have a strong negative correlation with the levels of soil available nitrogen and potassium. In contrast, there was a substantial positive correlation between the important value of grass and both soil total carbon and available potassium. Conversely, there was a strong negative relationship between the importance value of sedges and both total soil carbon and phosphorus. These findings indicate that the linkages between soil properties and plant functional groups varied across different recovery periods. This study would shed new light on the restoration in the Zoige desertified alpine meadows. [ABSTRACT FROM AUTHOR]

[Objective]To understand the community structure and soil environment status of the mountain top dwarf forest in Yangming Mountain, Hunan. [Method]A field investigation was conducted on the mountaintop dwarf forest in Yangming Mountain, Hunan Province, and the soil of the habitat was measured. [Result]The results showed that a total of 37 families, 51 genera, and 68 species of plants were recorded in the low forest sample plot on the mountaintop of Yangming Mountain. Among them, Rhododendron are the dominant genera in the tree layer and shrub layer. Rhododendron fortunei occupies an absolute dominant position in the number, height and importance value, and showing singledominant community structure. The important values of tree layer, shrub layer and herb layer were significantly correlated with OM and TN(P< 0. 05). [Conclusion]The mountaintop dwarf forest in Yangming Mountain, Hunan Province is a special community variant formed by the longterm development of subtropical evergreen broad-leaved forest in a special mountaintop habitat, with structural characteristics of single superior species communities; Among them, soil factors are of great significance for the development of subtropical mountaintop vegetation. [ABSTRACT FROM AUTHOR]

Rhizospheric arbuscular mycorrhizal fungi (AMF) are vital for the growth of navel oranges (Citrus sinensis Osbeck). However, the molecular diversity of AMF communities associated with navel oranges in the field is largely unknown. This study employed Illumina MiSeq sequencing to reveal the effects of cultivars and habitats on the rhizospheric AMF community. The results showed Glomus and Glomus_sp as the dominant genus (97.0%) and species (22.9%), respectively. The effects of cultivars were higher on rhizospheric AMF diversities and lower on AMF community compositions, when compared with those of habitats. No significant differences in the AMF community diversity and richness were observed between cultivars, whereas the rhizospheric AMF community compositions significantly varied between habitats. The AMF diversity (Shannon and Simpson indices) was negatively correlated with organic matter (OM) content, but positively correlated with available potassium (AK) content (p < 0.05). Both AK and OM were the most important soil factors that affected the AMF community structure. Thus, to regulate the rhizospheric AMF communities of navel oranges, OM inputs should be reduced and K inputs must be increased, which could benefit the functional diversity of AMF. [ABSTRACT FROM AUTHOR]

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Given the developmental program outlined in United Nations Sustainable Development Goal 15 (Life on Land) and the to effectively address the challenge of biodiversity decline while mitigating the adverse effects of climate change, particularly drought, on terrestrial forest ecosystems, a fundamental reorientation of global forest restoration paradigms is warranted. It is imperative to move beyond a narrow emphasis on expanding forest area and instead prioritize the enhancement of biodiversity and functional attributes within these ecosystems. However, the differential response mechanisms of forest ecosystem functional communities and main plant functional types (PFTs) to environmental factors, especially soil and topography, remains unclear, especially at plant level. Here, we divided the functional communities of 93 sites in the study area into seven groups through Two‐way indicator species analysis (TWINSPAN), and studied the different functional communities, namely dynamic succession, species richness, and PFT compositional differences. We also analyzed the various PFTs and functional community response mechanisms to soil and topographic factors using canonical correspondence analysis (CCA). The main results were as follows: (1) With the successional stages of PFTs, vegetation diversity across multiple functional communities inceased, tree and shrub proportions and importance increased, while herbs decreased. (2) From the arid and barren areas (i.e., G2), to the humid and fertile areas (i.e., G6 and G7), various compositional PFT differences, and their responses to soil and topographic factors, were found, namely, xerophytic, annual and biennial species gradually changed to mesophytic, hygrophytic, and perennial species (richness increased 6.94 ~ 27.33%, important value (IV) increased 8.73 ~ 29.45%) for shrubs and herbs. (3) Functional communities in various successional stages display distinct sensitivities to soil and topographic factors, as evidenced by a notable increase in the richness and IV of deciduous broad‐leaved tree species, rendering their communities more responsive to SOC and AS, whereas evergreen coniferous trees (e.g., Pinus tabuliformis Carr.) were sensitive to altitude (AL) and exhibited a tendency to transition from plantations to natural secondary forests predominantly at higher altitudes (above 1200 m). Our findings suggest that site conditions influence scenarios, and that different PFT responses and adjustments to soil and topography factors affect whole functional community dynamic succession processes, which can profoundly impact forest ecosystem function predictions based on PFT changes in the Loess Plateau of China. [ABSTRACT FROM AUTHOR]

Desertification has a significant impact on the Zoige meadow. Research efforts are directed towards the rehabilitation of the Zoige desertified alpine meadow, specifically in understanding the soil’s physical and chemical characteristics and the functional groupings of plants. However, the relationships between plant functional groups and soil properties remains uncertain. The primary objective of this study is to investigate the correlation between plant functional groups and soil nutrients across various stages of restoration. This study examined important value of plant functional groups, as well as variations in several soil characteristics, such as soil total nitrogen, total carbon, total phosphorus, available nitrogen, available potassium, available phosphorus, and soil pH during the stages of recovery. The results showed that the relative significance of importance values differed across distinct functional groups during different stages of recovery. The important value of legumes was found to have a strong negative correlation with the levels of soil available nitrogen and potassium. In contrast, there was a substantial positive correlation between the important value of grass and both soil total carbon and available potassium. Conversely, there was a strong negative relationship between the importance value of sedges and both total soil carbon and phosphorus. These findings indicate that the linkages between soil properties and plant functional groups varied across different recovery periods. This study would shed new light on the restoration in the Zoige desertified alpine meadows.

Biomass in forests sequesters substantial amounts of carbon; although the contribution of aboveground biomass has been extensively studied, the contribution of belowground biomass remains understudied. Investigating the forest biomass allocation is crucial for understanding the impacts of global change on carbon allocation and cycling. Moreover, the question of how climate factors affect biomass allocation in natural and planted forests remains unresolved. Here, we addressed this question by collecting data from 384 planted forests and 541 natural forests in China. We evaluated the direct and indirect effects of climate factors on the belowground biomass proportion (BGBP). The average BGBP was 31.09% in natural forests and was significantly higher (38.75%) in planted forests. Furthermore, we observed a significant decrease in BGBP with increasing temperature and precipitation. Climate factors, particularly those affecting soil factors, such as pH, strongly affected the BGBP in natural and planted forests. Based on our results, we propose that future studies should consider the effects of forest type (natural or planted) and soil factors on BGBP. [ABSTRACT FROM AUTHOR]

Global warming will increase the greenhouse gas (GHG) fluxes of permafrost regions. However, little is known about the difference in GHG fluxes among different types of permafrost regions. In this study, we used the static opaque chamber and gas chromatography techniques to determine the fluxes of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) in predominantly continuous permafrost (PCP), predominantly continuous and island permafrost (PCIP), and sparsely island permafrost (SIP) regions during the growing season. The main factors causing differences in GHG fluxes among three types of permafrost regions were also analyzed. The results showed mean CO2 fluxes in SIP were significantly higher than that in PCP and PCIP, which were 342.10 ± 11.46, 105.50 ± 10.65, and 127.15 ± 14.27 mg m−2 h−1, respectively. This difference was determined by soil temperature, soil moisture, total organic carbon (TOC), nitrate nitrogen (NO3−-N), and ammonium nitrogen (NH4+-N) content. Mean CH4 fluxes were -26.47 ± 48.83 (PCP), 118.35 ± 46.93 (PCIP), and 95.52 ± 32.86 μg m−2 h−1 (SIP). Soil temperature, soil moisture, and TOC content were the key factors to determine whether permafrost regions were CH4 sources or sinks. Similarly, PCP behaved as the sink of N2O, PCIP and SIP behaved as the source of N2O. Mean N2O fluxes were -3.90 ± 1.71, 0.78 ± 1.55, and 3.78 ± 1.59 μg m−2 h−1, respectively. Soil moisture and TOC content were the main factors influencing the differences in N2O fluxes among the three permafrost regions. This study clarified and explained the differences in GHG fluxes among three types of permafrost regions, providing a data basis for such studies. [ABSTRACT FROM AUTHOR]

Soil fungi are essential to soil microorganisms that play an important role in the ecosystem's soil carbon cycle and mineral nutrient transformation. Understanding the structural characteristics and diversity of soil fungal communities helps understand the health of forest ecosystems. The transition from tropical rainforest to artificial forest greatly impacts the composition and diversity of fungal communities. Hainan Limushan tropical rainforest National Park has a large area of artificial forests. Ecologists have conducted in-depth studies on the succession of animals and plants to regenerate tropical rainforests. There are few reports on the diversity of soil fungi and its influencing factors in the succession of tropical rainforests in Limu Mountain. In this study, 44 soil samples from five different stands were collected in the tropical rainforest of Limushan, Hainan. High-throughput sequencing of rDNA in its region was used to analyze fungal communities and study their α and β diversity. Analysis of variance and multiple regression models was used to analyze soil variables and fungal functional groups to determine the effects of interaction between fungi and environmental factors. A total of 273,996 reads and 1290 operational taxonomic units (OTUs) were obtained, belonging to 418 species, 325 genera, 159 families, eight phyla, 30 classes, and 73 orders. The results showed that the composition of soil fungal communities in the five stands was similar, with ascomycetes accounting for 70.5% and basidiomycetes accounting for 14.7%. α and β diversity analysis showed that soil fungi in Limushan tropical rainforest had high abundance and diversity. Multiple regression analysis between soil variables and functional groups showed that organic matter, TN, TP, TK, and AK were excellent predictors for soil fungi. TP was the strongest predictor in all functional groups except soil saprotroph. Organic matter and total nitrogen were the strongest predictors of soil rot. The transformation from tropical rainforest to artificial forest in Limushan did not change the soil fungal community structure, but the richness and diversity of soil fungi changed. The forest transformation did not lead to decreased soil fungal abundance and diversity. Different vegetation types and soil properties affect the diversity of soil fungal communities. We found that Caribbean pine plantations can improve soil fungal diversity, while long-term Eucalyptus spp. plantations may reduce soil fungal diversity. [ABSTRACT FROM AUTHOR]

Siraitia grosvenorii, a medicinal plant with continuous cropping, is cultivated in southern China. Changes in the soil microbial community during continuous cropping can cause soil-borne diseases in S. grosvenorii. This experimental study aimed to determine the differences in the arbuscular mycorrhizal fungi (AMF) community structure and root colonization in the rhizosphere soil of S. grosvenorii with different continuous cropping years and altitudes. We tested three altitude gradients (low, 200–300 m; middle, 500–600 m; and high, 700–800 m) and four continuous cropping years (1, 2, 3, and 5 years). AMF colonization, along with AMF spore density, and the soil physicochemical properties of S. grosvenorii roots at different altitudes and continuous cropping years were determined. Illumina high-throughput sequencing was used to determine the molecular diversity of AMF in the rhizosphere of S. grosvenorii as they exhibited a symbiotic relationship. The AMF species in the rhizosphere soil of S. grosvenorii included 28 species of nine genera, including Glomus, Claroideoglomus, Acaulospora, Paraglomus, Ambispora, and so on. With an increasing altitude, the AMF colonization of S. grosvenorii roots increased significantly (p < 0.01); available phosphorus (AP) content was negatively correlated with AMF colonization (p < 0.01). Glomus and Paraglomus were the common dominant genera in the rhizosphere soil of S. grosvenorii planted for 2–5 years at a low altitude and 1 year at middle and high altitudes. The average relative abundance of Glomus increased with increasing continuous cropping years and altitude in the low-altitude and 1-year S. grosvenorii areas, respectively. Slightly acidic rhizosphere soil contributed to AMF colonization and improved the richness and diversity of the AMF community. Our results showed that altitude, AP, and pH are essential factors for predicting AMF infection and community changes in the S. grosvenorii rhizosphere. Here, Illumina high-throughput sequencing was used to study the species resources and community composition of mycorrhizal fungi in S. grosvenorii in the hilly areas of Guangxi, China. This study provides a theoretical basis for the application and practice of mycorrhizal fungi including the isolation and screening of dominant strains, inoculation of mycorrhizal fungi, and exploration of the effects of mycorrhizal fungi on the growth and active ingredients of medicinal plants. [ABSTRACT FROM AUTHOR]

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(1) Background: Korean pine (Pinus koraiensis) and Manchurian walnut (Juglans mandshurica) are the main tree species for plantation regeneration in Northeast China, and the mixed plantation of them is one of the typical measures adopted to address the decline in stand productivity in long-term monocultures. However, little is known about the effects of Korean pine and Manchurian walnut monocultures and mixed plantations on soil microbial diversity, composition, and functional groups. (2) Methods: We used ITS and 16S rRNA gene sequencing to detect fungal and bacterial communities and used the FUNGuild, FAPROTAX, and Bugbase databases to predict their functional groups. (3) Results: Fungal and bacterial alpha diversity were always higher in Manchurian walnut monocultures than in Korean pine monocultures. The plantation type had a greater impact on the fungal composition than the bacterial composition. The fungal functional groups were significantly affected by the plantation type (p < 0.05), while the bacterial functional groups were barely changed among all plantation types. The soil available nutrient content was the most important soil factor in shaping the microbial community structures and functional groups. (4) Conclusions: Shifts in fungal community compositions and functional groups might play a dominant role in soil nutrient cycling across the different plantation types in Northeast China. [ABSTRACT FROM AUTHOR]

How plants change functional traists to adapt to the environment has always been the focus of ecology. In order to explore the adaptive strategies of plant leaves at different succession stages in karst forest of Maolan, taking the dominant species in five different succession stages (herb, shrub, shrub-arbor, arbor and climax community stages) in Maolan Nature Reserve as the research object, the leaf functional properties and soil physical and chemical properties of dominant plants at different succession stages were measured. The results were as follows: (1) With the succession of vegetation, soil total nitrogen (STN) content, soil organic matter (SOM) content and soil water (SWC) content gradually increased, soil total phosphorus (STP) content and soil total potassium (STK) content first increased and then decreased, and soil pH value showed a decreasing trend as a whole. (2) With the succession of vegetation, leaf area (LA), leaf dry matter content (LDMC), leaf thickness (LT) and leaf carbon content (LCC) gradually increased. On the contrary, specific leaf area (SLA) and leaf potassium content (LKC), leaf nitrogen content (LNC) increased first and then decreased, and leaf phosphorus content (LPC) decreased first and then increased. (3) Redundant analysis showed that plants were mainly distributed in the soil environment of high pH and relatively low STK, STP, SWC, SOM and STN at the early succession stage. Plant leaves in the community took high SLA, LNC and LPC, and low LA, LDMC, LT and LWC. Plants at the late succession stage were mainly distributed in the soil environment of high moisture and nutrients. LDMC, LT, LA and LWC showed an upward trend compared with the early succession stage, and SLA, LNC and LPC showed a downward trend compared with the early succession stage. In conclusion, with the forward succession of vegetation, plants adapt to the environment by changing functional traits, and leaf functional traits change from open strategy in the early succession stage to conservative strategy in the late succession stage.

Mountainous rangelands provide key ecosystem goods and services, particularly for human benefit. In spite of these benefits, mountain grasslands are undergoing extensive land-cover change as a result of woody plant encroachment. However, the influence of topographic and soil factors on woody plant encroachment is complex and has not yet been studied comprehensively. The aim of this review was to establish current knowledge on the influence of topographic and soil factors on woody plant encroachment in mountainous rangelands. To find relevant literature for our study on the impact of topographic and soil factors on woody plant encroachment in mountain rangelands, we conducted a thorough search on ScienceDirect and Google Scholar using various search terms. Initially, we found 27,745 papers. We narrowed down the search to include only 66 papers published in English that directly addressed the research area. The effect of slope aspect and slope position on woody plant encroachment is complex and dynamic, with no universal consensus on their impact. Some studies found higher woody plant encroachment on the cooler slopes, while others found increased woody plant encroachment on the warmer slopes. Slope gradient has a significant impact on woody plant encroachment, with steeper slopes tending to have more woody plant encroachment than gentle slopes. Soil texture and depth are important soil factors affecting woody plant encroachment. Coarse-textured soils promote the growth of woody plants, while fine-textured soils limit it. The effect of soil depth on woody plant encroachment remain unclear and requires further research. Soil moisture availability, soil nutrient content and soil microbial community are influenced by topography, which in turn affect the woody plant growth and distribution. In conclusion, the spread of woody plants in mountainous rangelands is a complex and dynamic process influenced by a range of factors. Further research is needed to fully understand the mechanisms behind these interactions and to develop effective strategies for managing woody plant encroachment in mountainous rangelands.

Introduction: Fine roots are the critical functional organs of plants to absorb water and nutrients from the soil environment, while the relation between fine root morphological characteristics and yield & quality has received less attention for medicinal plants. Methods: Therefore, we investigated the relationship between fine root morphological characteristics and biomass & gypenosides content. We explored the primary environmental drivers of fine root indicators for Gynostemma longipes from three provenances cultivated at two altitude habitats. Results: At the end of the growing season, compared with the low-altitude habitat, the underground biomass of G. longipes in the high-altitude habitat increased significantly by 200%~290% for all three provenances. The response of gypenosides content to different altitude habitats varied with provenance and plant organs. The biomass of G. longipes strongly depended on the fine root characteristic indicators (P < 0.001), fine root length density, and fine root surface area. Our results also showed that the harvest yield of G. longipes could be effectively increased by promoting the growth of fine roots per unit leaf weight (P < 0.001, R² = 0.63). Both fine root length density and fine root surface area had strong positive correlations with soil nutrient factors (R² > 0.55) and a strong negative correlation with soil pH (R² > 0.48). In a word, the growth of G. longipes is strongly controlled by the fine root morphological characteristics through the response of fine roots to soil nutrient factors and pH. Discussion: Our findings will help to deepen the understanding of the root ecophysiological basis driven by soil factors for the growth and secondary metabolites formation of G. longipes and other medicinal plants under changing habitat conditions. In future research, we should investigate how environmental factors drive plant morphological characteristics (e.g., fine roots) to affect the growth & quality of medicinal plants over a longer time scale. [ABSTRACT FROM AUTHOR]

[Objective] Tt is important to investigate the relationship between soil water and each environmental factor in the deep profile after vegetation change in the Loess Plateau and to identify the main controlling factors for the comprehensive regulation of soil water. Methods] Soil samples were collected from farmland, grassland and the 15 m depth of the habitation of salix psammophila and Populus in Dingbian County, northern Shaanxi. The soil samples were analysed using traditional statistics and wavelet coherence analysis. Results] The order of magnitude of soil water content and storage in ()一15 m was farmland〉grassland a salix psam m op hila '> pop la r, with water deficit of 81 0 mm, 1 375 mm, 1 371 mm and 1 7 62 m m, respectively. Based on wavelet coherence analysis of control factors, soil electrical conductivity (EC) was found to be the single dominant factor explaining water transport, and the area of positive correlation between EC and soil water was found throughout the scales. The two-factor combinations that combined effect of farmland are EC and sand, and magnetic susceptibility and sand for the lands grown salix psammophila and poplar. The two-factor combinations enhanced the degree of coherence mainly at large scales. Conclusion] Deep soil water is more influenced by soil properties, but plant root conditions can seriously perturb the relationship between water and soil properties. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)