Search Results (1,142)

Plants are increasingly exposed to simultaneous warming, drought, and herbivory, yet how invasive and native species regulate carbon allocation under these interacting stressors remains poorly understood. We conducted a full-factorial greenhouse experiment manipulating temperature (+3 °C), soil water availability, and herbivory to compare carbon allocation responses in the invasive Solidago canadensis and its native congener S. decurrens. Drought emerged as the dominant driver of carbon reallocation, shifting investment away from biomass production and photosynthetic function toward belowground allocation, osmotic adjustment, defense, and structural reinforcement. Herbivory imposed additional carbon demands and modified drought-induced responses, particularly by constraining phenolic accumulation under combined stress, whereas warming had comparatively weaker and largely context-dependent effects. Our results showed that the two species differed in how carbon was distributed under stress: S. canadensis maintained greater biomass, chlorophyll, soluble sugars, and hemicellulose, whereas S. decurrens showed stronger investment in structural components. Structural equation models further revealed contrasting pathways linking physiological, defensive, and structural traits to biomass, supporting species-specific strategies of carbon allocation under multiple stressors. These findings suggest that the greater carbon-allocation flexibility observed in S. canadensis may contribute to maintaining performance under increasingly variable environmental conditions. However, because S. canadensis was raised directly from field-collected seeds without a refresher generation, potential maternal environmental effects cannot be completely excluded. Overall, our findings identify coordinated redistribution of carbon among competing functional pools as a potential mechanism underlying contrasting stress responses in these two congeneric species. Full article

The stingless bee Tetragonisca angustula (Apidae: Meliponini) is ecologically and socioeconomically important in northern Peru, yet the factors shaping its habitat suitability remain poorly quantified. We modeled current suitability across Amazonas and San Martín using 28 occurrence records: 17 field-georeferenced hive locations and 11 records from the Global Biodiversity Information Facility (GBIF). An initial set of 28 climatic, vegetation, hydrological, topographic, and edaphic predictors was reduced to 15 variables after repeated variance inflation factor analyses. Maximum Entropy models were calibrated with linear, quadratic, and hinge features, four regularization multipliers, 20 bootstrap replicates, and a 75:25 training–testing partition. A multiplier of 1.5 was selected for its higher minimum test AUC across replicates (0.72), indicating more consistent worst-case performance (training AUC = 0.94 ± 0.02; test AUC = 0.84 ± 0.07). Forest cover contributed most to model fit (31.7%), whereas predictions were most sensitive to slope (27.2% permutation importance), precipitation of the coldest quarter (14.2%) and soil organic carbon (13.3%). Suitability peaked at intermediate forest cover (~50%) and gentle slopes (~4°). Applying the 10th-percentile training-presence threshold, 1,190,582 ha (13.2%) were classified as suitable, concentrated in mixed forest–agricultural landscapes rather than continuous lowland forest. Vegetation structure and terrain, not climate alone, shaped predicted suitability; given uneven sampling, these patterns require field validation. Full article

Changing disturbance regimes and uncertain recovery trajectories under global change have created a need for conceptual models to guide forest management within a sustainability framework. This conceptual article develops on operational framework for ecosystem memory in forest ecosystems. Conventional views of resilience may foster the misleading assumption that ecosystem development follows a fixed trajectory within the boundaries of the natural range of variation. However, climate change may transform resilience mechanisms, causing forest ecosystems to shift beyond their historical range of variation. Under such conditions, the concept of ecosystem memory offers a framework for analyzing and quantifying temporal system properties. The constraints inherited through memory patterns are themselves likely to be modified under changing environmental conditions. A valid interpretation of ecosystem memory requires a clear ontological understanding of memory components as material entities organized under temporal and spatial constraints. The human memory metaphor is an appealing entry point for understanding ecosystem memory but risks erroneously attributing semantic encoding and representational processes to ecological systems, where no such mechanisms exist. Based on a narrative synthesis of 39 publications, supplemented by an updated Web of Science search that identified 396 records, we develop an operational ecosystem-memory framework that distinguishes persistent ecological legacies from functionally active memory by linking ecological imprints, ecosystem engrams, and measurable ecosystem responses. The framework provides a basis for identifying and monitoring measurable legacy variables, including deadwood, retained trees, regeneration, soil properties, and refugial structures, in post-disturbance forest management. Full article

Biochar has been widely applied for immobilization of potentially toxic elements (PTEs) in contaminated soils; however, its effects on metal transport under transient unsaturated conditions remain insufficiently understood. This study investigated the adsorption, desorption, and transport behavior of Pb²⁺ and Cd²⁺ in biochar-amended soils by combining batch experiments, unsaturated conditions column experiments, and transport modeling. The adsorption kinetics, isotherms, and desorption characteristics of Pb²⁺ and Cd²⁺ were evaluated under different biochar levels, and their redistribution during unsaturated infiltration was further analyzed using soil–water-dependent models. Biochar increased the apparent adsorption capacity of both metals, with a stronger response observed for Pb²⁺ than Cd²⁺. The Elovich and two-constant models provided better statistical descriptions of adsorption kinetics than the pseudo-second-order model, indicating that adsorption rate behavior involved heterogeneous and multi-rate processes. Freundlich fitting showed that Pb²⁺ and Cd²⁺ exhibited non-ideal adsorption behavior, while desorption experiments demonstrated a stronger reduction in apparent Pb²⁺ release compared with Cd²⁺ under biochar. Under transient unsaturated infiltration, Pb²⁺ and Cd²⁺ exhibited distinct transport patterns. Pb²⁺ redistribution was adequately described by a linear partitioning relationship, with R² values ranging from 0.988 to 0.990, indicating relatively stable solid–liquid partitioning within the tested conditions. In contrast, Cd²⁺ showed stronger dependence on soil–water conditions, and an empirical nonlinear water-dependent model improved model performance, increasing R² values from 0.533–0.652 for the linear model to 0.903–0.973. The results suggest that biochar effects on potentially toxic element migration under unsaturated conditions are element-specific, involving both apparent sorption enhancement and water-dependent redistribution processes. This study highlights that biochar performance in potentially toxic elements remediation should not be evaluated solely based on equilibrium adsorption capacity. Under field-relevant unsaturated conditions, amendment effectiveness may also depend on interactions between metal-specific retention behavior and soil hydraulic variability. Further studies integrating structural characterization, long-term aging, and reactive transport modeling are required to validate these processes under heterogeneous field conditions. Full article

In the primary spruce-fir-Korean pine forest affected by historical windthrow, soil water-holding capacity shows complex spatial associations with forest microenvironment and soil physicochemical properties. However, its spatial variability and multi-factor hierarchical association pathways remain poorly understood. Taking the primary spruce-fir-Korean pine forest on a historically windthrow-affected site in the Liangshui National Nature Reserve, Xiaoxing’an Mountains, China as the research object, geostatistics and partial least-squares structural equation modeling were used to analyze the spatial pattern of topsoil (0–20 cm) water-holding capacity and its environmental association pathways. The results showed saturated, capillary and field water-holding capacities of topsoil exhibited moderate variability and strong spatial autocorrelation (all nugget to sill ratios < 25%), showing a patchy distribution. No significant direct association was detected between windthrow mechanical disturbance intensity and topsoil water-holding capacity. Bulk density (path coefficient = −0.685, p < 0.001) and soil porosity (path coefficient = 0.273, p < 0.001) had significant direct associations with soil water-holding capacity, whereas soil particle size distribution showed no significant effect (p > 0.05). Canopy structure and understory microclimate exerted indirect associations with soil water-holding capacity via soil structure; litter showed no significant associative effect (p > 0.05). These results indicate that soil water-holding capacity on the historically windthrow-affected site was not randomly distributed, but presented an ordered patchy pattern closely related to in-plot micro-environmental factors. Full article

Windthrow is a major disturbance risk for radiata pine (Pinus radiata D. Don) plantations, but operational susceptibility models must transfer across regions and storm events. We developed a multi-regional framework combining airborne laser scanning (ALS), aerial imagery, mapped stand and site variables, climate, soils, and event-period weather. These data were used to detect storm damage and model windthrow susceptibility following major storm events in Gisborne, Hawke’s Bay and Tasman, New Zealand. Windthrow was mapped from repeat ALS canopy-height differencing in Gisborne and Hawke’s Bay, and from post-storm aerial imagery in Tasman, producing 29,244 balanced windthrow and no-windthrow plot observations. Random-forest models were evaluated using stand-grouped, spatially blocked and leave-one-region-out validation. Stand structure provided the strongest predictive signal, with windthrow concentrated in older, taller and higher-volume stands. Adding long-term climate produced the largest improvement beyond the Base stand/site formulation, giving a pooled ROC–AUC of 0.901 ± 0.013. Spatially blocked ROC–AUC for the selected model ranged across the three regions from 0.780 to 0.856, while leave-one-region-out ROC–AUC ranged from 0.649 to 0.802, demonstrating useful but region-dependent transfer. Adding soil and event-period weather did not consistently improve transferability. Prevalence-calibrated conditional scenario estimates increased with stand development under the mapped regional prevalence and the conditions represented by the reference events. These estimates provide a scalable basis for comparative windthrow-risk screening but should not be interpreted as independently validated absolute or annual windthrow probabilities. Full article

Belowground multitrophic communities and their potential associations are important biological foundations for the maintenance and recovery of soil ecosystem functions. However, it remains unclear how soil micro-food web composition and network complexity are linked to soil ecosystem multifunctionality across different post-cropland restoration states. In this study, we used a space-for-time substitution approach and selected cropland and three post-cropland restoration states in the Taihang Mountains, including shrub–grassland, Populus spp. plantation, and Robinia pseudoacacia plantation, each with five plots, to examine changes in bacterial, fungal, and nematode communities, soil micro-food web network complexity, and soil ecosystem multifunctionality in topsoil and subsoil. Compared with cropland, bacterial diversity was higher in the shrub–grassland, Populus spp. and R. pseudoacacia plantations, whereas fungal diversity showed a marked decline in the Populus spp. plantation. Furthermore, the topsoil of the R. pseudoacacia plantation exhibited much higher micro-food web network complexity and soil multifunctionality than cropland, whereas differences among land-use types were relatively small in the subsoil. Structural equation modeling indicated that vegetation type, soil depth, soil moisture content, microbial diversity, nematode diversity, and soil micro-food web network complexity jointly explained 94% of the variation in soil ecosystem multifunctionality (R² = 0.94). Further random forest analysis identified soil depth as the most important predictor of soil ecosystem multifunctionality, followed by soil micro-food web network complexity; among biological variables, fungal diversity, bacterial diversity, omnivorous-predatory nematode diversity, and herbivorous nematode diversity also showed relatively high importance. Overall, these results suggest that changes in soil ecosystem multifunctionality across post-cropland restoration states were strongly soil-depth-dependent, and that soil micro-food web diversity and network complexity can serve as important biological indicators for assessing restoration outcomes. Full article

Ground deformations induced by underground mining significantly affect the geometric condition and serviceability of buildings located in mining areas. Conventional assessments are commonly based on ground deformation indicators, which do not necessarily reflect the actual structural response. This study presents a terrestrial laser scanning (TLS)-based methodology for assessing the three-dimensional deformation of an eleven-storey residential building located in the Legnica–Głogów Copper District (LGCD), Poland. The analysis was performed using a high-density point cloud acquired from ten scanning positions. Following registration and filtering, building geometry was reconstructed and corner positions were determined from 123 horizontal cross-sections. Horizontal displacements, tilt profiles, and rotation about the vertical axis were subsequently analysed within a local coordinate system. The results revealed pronounced spatial variability in both displacement magnitude and direction. The maximum horizontal displacement reached approximately 0.18 m, corresponding to a local tilt of 5.9 mm/m. Corner displacements at the highest common observation level ranged from 8.6 mm to 178.3 mm, indicating that the observed geometry is inconsistent with a simple rigid-body model subjected to uniform tilting. Analysis of geometric changes with height further identified an overall increase in torsional rotation with height, accompanied by local variations. Comparison of TLS-derived geometry with a theoretical mining-induced ground deformation model showed that the measured structural response does not directly reproduce the underlying ground deformation pattern. The largest discrepancies occurred along the building longitudinal axis, indicating that structural stiffness and soil–foundation–structure interaction significantly modify the transfer of ground movements to the superstructure. These results demonstrate the capability of TLS for detailed assessment of mining-affected buildings and provide quantitative insight into the relationship between ground deformation and actual structural response. Full article

More than six decades of human activity in Antarctica resulted in chronic diesel contamination of soils surrounding research stations. Phytoremediation assisted by the native vascular plant Deschampsia antarctica is one of the few remediation strategies compatible with the Antarctic Treaty System guidelines. Securing suitable root-associated microbial resources is central to this approach. This work characterized the bacterial communities of the rhizosphere and root endosphere of D. antarctica growing in a chronically diesel-contaminated soil at Carlini Station and in three pristine sites on 25 de Mayo (King George) Island, South Shetland Islands, combining culture-independent 16S rRNA gene amplicon sequencing, PICRUSt2 functional prediction and culture-dependent bacterial strain isolation. The rhizospheric microbial community was consistently more diverse than those inhabiting the endosphere and was more strongly structured by site and associated soil physicochemical variables, with the contaminated site showing the most distinct composition, whereas the endosphere remained comparatively stable and host-selected. The community associated with the chronically contaminated site showed pronounced compositional differences and higher predicted abundances of hydrocarbon-degradation pathways in the rhizosphere. Polaromonas, Rhodococcus, Mycobacterium and Devosia were repeatedly associated with the community from the contaminated site across taxonomic, biomarker and predicted functional analyses. Members of the genera Polaromonas, Rhodococcus and Devosia were also recovered in culture. These taxa represent suitable candidates for the future development of microbe-assisted phytoremediation strategies in Antarctica. Full article

This review aims to synthesise existing knowledge on the efficacy, underlying mechanisms, and practical relevance of biostimulants within low-input agroecosystems, with particular emphasis on South Africa as a representative semi-arid, resource-constrained agricultural system, while highlighting broader implications for similar low-input agroecosystems in sub-Saharan Africa. This review paper reviews peer-reviewed and selected grey literature sources published between 1997 and 2026, retrieved through structured searches of Scopus, Web of Science, and Google Scholar using predefined keywords related to biostimulants, sustainable agriculture and South Africa. Across the literature, there is general agreement that biostimulants may indirectly support biodiversity through improved soil biological activity and reduced dependence on synthetic inputs, although direct field evidence remains limited. Methodologically, most studies are conducted under controlled or semi-controlled conditions, including greenhouses, growth chambers, and pot experiments. While these approaches allow for mechanistic understanding and precise variable control, they often fail to capture the complexity of field environments typical of low-input farming systems. This review synthesises peer-reviewed literature identified through structured searches of major databases utilising terms related to biostimulants, with an emphasis on studies conducted in both controlled environments and field settings. Evidence suggests that biostimulants can enhance plant physiological performance, improve stress tolerance, and contribute to more efficient resource use when integrated into appropriate management practices. However, their effectiveness is highly context-dependent, and they should not be considered substitutes for soil fertility management or sound agronomic practices. Future research, particularly in South Africa as a representative semi-arid and resource-constrained system, should prioritise field-based assessments and incorporate ecological indicators such as species abundance, pollinator visitation, and ecosystem resilience under biostimulant regimes to generate more robust and context-relevant evidence. Full article

Climate-related production variability and increasing market uncertainty pose significant challenges for Mediterranean olive systems. This study examines the long-term production dynamics, market vulnerability, and ecological functions of Mediterranean olive systems under climate change through an integrated assessment combining statistical production analysis, descriptive economic analysis, and a structured ecological literature synthesis. Olive and olive oil production trends were analyzed for Greece, Spain, Italy, and Portugal using FAOSTAT data (1960–2020), together with European Commission statistics (2010/11–2021/22) on production, prices, and trade. The results reveal significant long-term production trends, with greater year-to-year fluctuations observed in several countries, particularly after 2010. These fluctuations may reflect the combined influence of climatic variability and structural changes affecting Mediterranean agricultural systems, although their relative contribution was beyond the scope of the present study. Despite maintaining a leading position in global olive oil production and trade, the European Union recorded a 52% increase in export volume and a 125% increase in export value, highlighting both market expansion and increasing exposure to international market dynamics. The ecological synthesis indicates that traditional and low-input olive groves provide important ecosystem functions, including biodiversity conservation, soil protection, water regulation, and soil-carbon maintenance, supporting the long-term sustainability of Mediterranean olive systems. Overall, the findings highlight the need for integrated adaptation strategies combining environmentally sound land management, value-chain coordination, and policy support to strengthen the long-term sustainability of Mediterranean olive systems. Full article

Organic fertilizer and season are established sources of variation in tea plantation soil microbiomes. A repeated-measure field experiment was conducted in Yunnan, China, comprising an unfertilized control (CK), sheep manure (SM), pig manure (PM), rapeseed cake manure (RM), and commercial organic fertilizer (OF). The same 15 mature tea trees were sampled in spring, summer, and autumn, yielding 45 composite soil samples. Soil properties, as well as 16S rRNA gene and ITS amplicon profiles, were evaluated using mixed-effect models, restricted-permutation PERMANOVA, and design-adjusted partial redundancy analysis (pRDA). Fertilization regime, season, and their interaction showed property-specific associations, most clearly for alkali-hydrolyzable nitrogen, available phosphorus, and available potassium. Bacterial alpha diversity was more responsive than fungal alpha diversity. Both factors were significantly associated with bacterial and fungal community structures. Season accounted for most bacterial variation (68.70%), whereas fungal variation was associated more evenly with season (27.33%) and fertilization regime (18.61%); no significant interaction was detected for either group. Nine fungal genera retained significant treatment-associated differences after FDR correction, whereas the bacterial genus-level patterns remained exploratory. After conditioning for fertilization regime and season, measured soil variables collectively explained 6.51% and 13.56% of bacterial and fungal variation, respectively, but no individual variable remained significant after FDR correction. Because fertilizer inputs were not nutrient-standardized, treatment contrasts represent integrated material-and-dose regimes rather than isolated fertilizer-type effects. These context-specific results illustrate the value of repeated seasonal sampling with design-adjusted analyses for evaluating practical fertilization regimes. Full article

This study characterized regional variation in faba bean rhizosphere bacterial communities across a broad survey of the Qinghai Plateau and examined their associations with soil and spatial factors. Rhizosphere soil samples were collected from 15 faba bean-growing field sites across Haidong City, Xining City, and Hainan Tibetan Autonomous Prefecture, Qinghai Province, China, spanning elevations from 1842.9 to 3206.3 m. Nine within-site subsamples were collected at each field site, with the field site treated as the independent unit of replication. Soil physicochemical properties were measured, and bacterial communities were characterized by high-throughput sequencing of the 16S rRNA gene. At the site level, bacterial alpha-diversity indices showed numerical variation among the three regional elevation groups, but did not differ significantly. Bacterial community composition differed among groups in the site-level PERMANOVA based on Bray–Curtis dissimilarities (pseudo-F_2.12 = 1.789, R² = 0.230, p = 0.031), although substantial overlap among sites remained. However, a conservative locality-level sensitivity analysis was not significant (p = 0.060). Geographic distance was significantly associated with bacterial community dissimilarity, whereas elevation difference showed no detectable independent association after controlling for geographic distance, indicating a substantial contribution of spatial structure to the observed community differentiation. Dominant phylum-level composition was broadly conserved across sites, while genus-level relative abundances showed descriptive spatial variation. Neither RAVD-based compositional consistency nor community-level niche breadth differed significantly among groups. Among the measured soil properties, only pH differed significantly, whereas most nutrient variables did not. Overall, the study revealed spatially structured regional differentiation in faba bean rhizosphere bacterial communities across the Qinghai Plateau. The observed patterns likely reflect the combined influence of geographic structure, elevation, background soil conditions, agricultural management, plant phenology, and other unmeasured environmental factors, which could not be independently disentangled in the present survey. Full article

Understanding the ecological adaptability of Pennisetum giganteum (JUJUNCAO) and its long-term effects on rhizosphere microecology is critical for vegetation restoration in fragile ecosystems. In this study, we investigated the soil physicochemical properties and microbial community structure and function in the rhizosphere of P. giganteum cultivated for 1 and 3 years (Y1, Y3), alongside pre-planting soil (Y0), in a dry-hot valley in Chuxiong, Yunnan, China. Following three years of cultivation, the soil total carbon (TC), organic carbon (SOC), total nitrogen (TN), nitrate nitrogen (NO₃⁻-N), total phosphorus (TP), and available phosphorus (AP) showed significant increases of 84.18%, 96.09%, 61.32%, 212.47%, 24.71%, and 22.19%, respectively, whereas the soil pH remained stable. Fungal communities showed significant declines in diversity and richness and a fundamental structural shift as early as one year after planting. In contrast, prokaryotic communities showed a relatively stable structure. Soil carbon and nitrogen variables were the factors most strongly associated with microbial community composition, and long-term cultivation concurrently enriched the arbuscular mycorrhizal fungi Septoglomus and genera containing potential plant pathogens such as Fusarium and Nectria. The relative abundance of Nectria was positively correlated with the soil carbon and nitrogen contents (p < 0.05), suggesting a potential ecological trade-off between beneficial symbiosis and disease risk. Predicted functional pathway composition indicated a shift in microbial metabolism from basal pathways of phospholipid and nucleotide synthesis toward carbon-nitrogen metabolism via PWY-3781 and the glyoxylate shunt, with fungal community turnover more pronounced. Consequently, P. giganteum demonstrates considerable potential for ecological restoration in dry-hot valleys; however, long-term cultivation deserves attention due to potential nitrate loss and the accumulation of taxa containing potential pathogens, with fungal communities serving as sensitive bioindicators of soil health. Full article

The invasive golden apple snail (Pomacea canaliculata) threatens rice agroecosystems, yet its direct density-dependent effects on flooded paddy soil biogeochemistry and bacterial communities remain unclear. We established flooded soil microcosms with four snail densities (0, 2, 4, and 6 snails/box) for 20 days, without external food inputs. Soil dissolved organic carbon (DOC), ammonium nitrogen (NH₄⁺-N), nitrate nitrogen (NO₃⁻-N), and the activities of β-glucosidase, N-acetyl-β-D-glucosaminidase, urease, and dehydrogenase were measured, and bacterial communities were characterized by full-length 16S rRNA gene amplicon sequencing. Snail density was significantly and positively related to all three nutrient variables and all four enzyme activities. The dominant bacterial phyla and genera remained stable, and bacterial α-diversity changed little among treatments, despite a small but significant increase in Simpson diversity in the high-density treatment. PERMANOVA detected significant differences in overall bacterial community structure among density treatments, while environmental fitting identified DOC, urease, and dehydrogenase as variables significantly associated with community variation. These findings indicate that living golden apple snails can alter nutrient availability, soil biochemical activity, and bacterial community organization in flooded paddy soil, revealing a belowground pathway through which this invader may influence paddy ecosystem functioning. Full article