Search Results (1,147)

In rocky mountainous regions characterized by shallow, barren soils and water scarcity, non-rainfall water, such as condensation, plays a crucial ecological role in mitigating seasonal drought in forest trees. To enhance the water-use capacity of vegetation, this study utilized a previously developed eco-friendly PVA–CS/SA–Ca²⁺ hydrogel. The primary objective was to elucidate the synergistic mechanisms by which the hydrogel optimizes condensed water utilization and drives the ecophysiological recovery of Pinus tabuliformis and Platycladus orientalis, two keystone afforestation species in northern China. Utilizing a controlled environmental chamber to simulate the condensation and humidification process, the experiment established three treatments: a control group (CK), a pot-sealed group (PS, to isolate soil water absorption), and a hydrogel-amended group (Hydrogel-Root Wrapping, HRW). To comprehensively evaluate the water utilization mechanisms, the amount of condensed water captured by the system was quantified, and hydrogen isotope tracing techniques were employed to precisely track water transport pathways and contribution rates. Concurrently, key physiological parameters were systematically determined, including leaf water potential, stomatal conductance, leaf water content, net photosynthetic rate, and transpiration rate. The results demonstrated the following: (1) the hydrogel significantly enhanced the condensation water capture capacity of the system. The net mass gains of the Pinus tabuliformis and Platycladus orientalis systems under the HRW treatment reached 26.3 g and 32.9 g, respectively, which represented 1.17 and 1.30 times those of the CK treatment, and 1.52 and 1.54 times those of the PS treatment. (2) Isotope tracing confirmed that both tree species possess significant Foliar Water Uptake (FWU) capacity. Following condensation, the δ²H values in the leaves of Platycladus orientalis and Pinus tabuliformis surged to 113.5‰ and 85.3‰, respectively, with stem δ²H values increasing by 31‰ and 22‰ compared to their initial baseline. (3) The introduction of the hydrogel in the HRW treatment provided 11.2% and 10.9% of the stem water supply for Platycladus orientalis and Pinus tabuliformis, respectively, thereby reducing their dependence on soil water by 8.3% and 13.1%. In contrast, there was no significant difference in the fractional contribution of condensation water to stem water between the PS and CK treatments. (4) Regarding physiological responses, the application of the hydrogel material effectively improved the physiological status of the plants. The leaf water potentials of Pinus tabuliformis and Platycladus orientalis increased to −0.15 MPa and −1.32 MPa, respectively. Concurrently, stomatal conductance (3.25 and 3.64 mm·s⁻¹) and leaf water content (58.4% and 67.4%) were significantly higher than those in the other treatments. In summary, the hydrogel can significantly enhance the capture, conversion, and utilization efficiency of condensation water by vegetation, effectively optimizing the water supply dynamics of the system. This provides key theoretical and technical support for ecological afforestation in difficult sites within rocky mountainous areas. Full article

Understanding the adaptive dynamics of social-ecological systems (SESs) is critical for regional sustainability as human–environment interactions intensify. However, existing indicator-based research frequently lacks a clear theoretical framework and methodological clarity when analyzing SES adaptation. Using complex adaptive system (CAS) theory as an interpretive lens, this research creates a social-ecological system (SES) adaptability evaluation framework that incorporates the pressure–state–response (PSR) model from a CAS perspective. This study examines the Huaihe River Ecological and Economic Belt (HREEB) as a case study, combining remote sensing (RS) and geographic information system (GIS) data from 28 prefecture-level cities from 2005 to 2020. The entropy-weight approach is used to create a composite adaptability index, and obstacle-degree analysis is used to identify key limiting factors, followed by an examination of spatiotemporal evolution patterns. The study found that: (1) SES adaptability in the HREEB increased steadily (mean annual growth rate: 3.97%), with the social subsystem exhibiting a larger connection with the overall trend and the ecological subsystem displaying greater volatility; (2) there was significant spatial heterogeneity, forming a “high in the east and west, low in the center” pattern (supported by a global Moran’s I = 0.535, p < 0.05); (3) obstacle degree analysis identified per capita afforestation area (ecological response), per capita GDP (social state), and population density (ecological pressure) as persistent key constraints. Full article

In this research we analyzed land cover/use processes and their impact on biodiversity in the Megalopolis of Mexico City. We used land cover/use databases from 1976 and 2018, both validated, improved and adapted for conducting landscape dynamic analysis. We also included records of 159 threatened species of fungi, vascular plants and vertebrates to construct spatially explicit biodiversity richness models based upon niche ecological algorithms. The results showed that human settlement encroachment (35%, 1892 km²) was the main factor driving land cover/use changes, significantly affecting rural and natural landscapes. The extent and location of the dramatic shrinking of agricultural land was clearly demonstrated (47.22%). Afforestation was the second most important land cover/use process occurring mainly on conversion of native grasslands and shrubland into forest cover mainly with non-local tree species. Biodiversity richness was depleted substantially, affecting 36.7% of the largest hotspots by human settlement encroachment. On the mountain peaks, as vestiges of temperate Nearctic ecosystems, with a large number of endemic and threatened species, remnants of the high potential richness of biodiversity are still conserved. The results are discussed in the light of interdisciplinary methodological approaches, potential water recharge, governance of territorial disputes, loss of cultural heritage and poorly implemented environmental policies. Furthermore, the study highlights the urgent need to generate an innovative model for development which gives equal importance to the conservation of natural and rural landscapes as a fundamental form of subsistence for human settlements. Protecting biocultural heritage is of paramount importance. The region’s genetic resources and cultural diversity are unique and have played a fundamental role in providing various benefits from nature to urban and rural inhabitants. These findings can serve as a guide for other similar megacities around the world. Full article

The expansion of Eucalyptus plantations has raised concerns about their effects on wildlife, yet the influence of stand-level management on roe deer remains poorly understood. We investigated how plantation management shapes roe deer responses in central Portugal using 375 camera-trap deployments from 2019 and 2020 and four session-specific single-season occupancy models that separated detection probability from site-use probability. Across sessions, stand size was retained mainly in the detection component, indicating that variation in camera-trap sampling coverage influenced detectability more consistently than ecological site use. Support for site-use effects varied among periods, but the strongest result emerged in the 2020 dry season, when site use was lower in reforestation stands than in afforestation stands and temporal responses differed among production regimens. The 2020 wet season also supported a positive effect of time since intervention on site use after accounting for broad spatial structure. By contrast, the 2019 wet season informed detection only, whereas the 2019 dry season showed non-linear relationships weakened by overdispersion and QAICc sensitivity. Overall, our findings indicate that Eucalyptus plantations should not be treated as ecologically uniform systems, because roe deer responses depend on when and how stands are managed, with reforestation representing the most disruptive phase. Full article

Restoration-oriented forest management is increasingly recognized as an important strategy for enhancing long-term carbon sequestration and rehabilitating degraded peri-urban forest landscapes. This study presents a scenario-based assessment of projected carbon sequestration trajectories under a National Reserve Forest Project implemented in peri-urban Wuhan, central China. Thirteen silvicultural models were grouped into three management pathways: intensive plantation cultivation, transformation of existing degraded stands, and tending of young and middle-aged forests. Carbon sequestration was evaluated over a 40-year assessment period (2024–2063) using a Biomass Expansion Factor-based accounting framework incorporating above- and belowground biomass, harvested wood products, and conservative baseline deductions consistent with national and provincial methodologies. The results indicate a sustained long-term increase in projected carbon sequestration despite periodic short-term declines associated with planned thinning and harvesting cycles. Transformation-oriented pathways contributed the largest cumulative project-scale sequestration and generally exhibited relatively strong area-normalized sequestration performance compared with intensive plantation and tending pathways. Intensive plantation systems displayed greater temporal fluctuation associated with shorter rotation cycles and repeated harvesting events. The analysis also highlights the importance of distinguishing between area-normalized sequestration efficiency and cumulative project-scale contribution, as models with moderate per-hectare performance generated substantial total carbon benefits because of their larger implementation area. The findings suggest that restoration-oriented management of existing degraded stands may provide a relatively stable long-term carbon-sequestration pathway in peri-urban forest systems where land availability for large-scale afforestation is constrained. The study also demonstrates the applicability of conservative scenario-based accounting frameworks for restoration-oriented forest carbon assessment and planning under data-limited conditions. Full article

Global warming and climate change have considerably enhanced worldwide environmental concerns since the 1970s. Therefore, researchers have extensively researched the nexus between renewable energy utilization and CO₂ emissions in the literature. However, the influence of afforestation and energy productivity along with renewable and nuclear electricity generation on CO₂ emissions has not been explored sufficiently in the associated literature regarding the multiple effects of these actors on the decarbonization process. Thus, this article analyzes the short- and long-term effects of afforestation, energy productivity, renewable and nuclear electricity production on CO₂ emissions in the BRICS states over the 1993–2021 term via robust bootstrap cointegration and causality tests. The findings confirm a cointegration interplay among CO₂ emissions, afforestation, energy productivity, renewable and nuclear electricity generation. Further, the cointegration coefficients demonstrate a negative influence of afforestation, energy productivity, renewable electricity generation on CO₂ emissions in most of the BRICS states in the long term, but a negative effect of nuclear electricity production only in China and the Russian Federation. The findings of causality examination also uncover that afforestation, energy productivity, and generation of renewable and nuclear electricity are effective tools in reducing CO₂ emissions, but their long-term effects are found to be relatively higher than short-term effects. These findings indicate that promotion of afforestation, along with energy productivity and electricity from renewables and nuclear sources is highly useful for curbing CO₂ emissions in the short and long term. Full article

Drought severely restricts the growth and establishment of Pinus sylvestris var. mongolica seedlings, whereas the mechanisms by which plant growth-promoting rhizobacteria improve host drought tolerance remain incompletely understood. In this study, strain A54 was evaluated under four drought gradients (ND, LD, MD, and SD) in a greenhouse pot experiment. Seedling growth, nutrient accumulation, physiological traits, rhizosphere bacterial communities, soil functional variables, genome annotation, and qRT-PCR were integrated to clarify the drought-alleviating effects of A54. At the strain level, A54 maintained growth and ACC deaminase-associated functional performance under PEG-induced osmotic stress. A54 inoculation alleviated drought-induced growth suppression, with seedling height increasing by 69.7% under MD and 87.7% under SD relative to the corresponding controls. A54 also improved nutrient maintenance, especially Stem TN and Leaf TK, enhanced antioxidant capacity, and reduced osmotic stress, membrane lipid peroxidation, and stress-hormone accumulation. In the rhizosphere, A54 reshaped bacterial community structure by increasing the proportion of persistent taxa and selectively enriching drought-associated taxa, especially Pseudarthrobacter. A54-treated soils also maintained higher levels of available nutrients and enzyme activities under drought. Genome annotation and representative gene expression further supported the functional potential of A54 in nitrogen metabolism, ACC deaminase-associated ethylene regulation, oxidative defense, and osmotic or ion homeostasis. supporting its role in enhancing drought tolerance. These findings support the potential application of A54 as a bio-inoculant to improve afforestation performance under water-limited conditions. Full article

This study aimed to reveal the rhizosphere microbial community structure, carbon–nitrogen–phosphorus (C-N-P) nutrient cycling processes, and functional gene characteristics of Pinus massoniana and Schima superba in mixed forests. Furthermore, we sought to elucidate the microbial mechanisms by which mixed-species afforestation enhances soil quality improvement, providing a theoretical basis in soil microbiology for the cultivation of these mixed forests. The research subjects included pure P. massoniana plantations (CLPs), pure S. superba plantations (CLSs), and individual P. massoniana (HJP) and S. superba (HJS) trees within mixed plantations (HJLs). We collected rhizosphere and bulk soil samples to analyze their physicochemical properties and enzyme activities. Metagenomic sequencing was employed to profile the rhizosphere microbial communities and functional genes involved in C-N-P cycling. Furthermore, by integrating a functional gene co-occurrence network analysis with structural equation modeling (SEM), we systematically elucidated the coupling relationships among the stand types, soil properties, microbial communities, and nutrient cycling. Mixed planting significantly improved soil quality; compared to the CLP and CLS forests, the nitrate nitrogen (NO₃⁻-N) content in the mixed forest soils increased by 121.01% and 120.10% (p < 0.05), and the activity of urease (URE) also significantly increased by 123.99% and 49.56%, respectively. Mixing significantly altered the microbial community structure. In the bacterial community of the mixed forests, the abundance of nitrogen-fixing and potentially phosphorus-solubilizing bacteria from the genera Paraburkholderia and Burkholderia increased. In the fungal community, the arbuscular mycorrhizal fungus Rhizophagus, which possesses a nutrient absorption advantage, exhibited absolute dominance, with its relative abundance ranging from 14.84% to 88.81%. The abundances of genes associated with denitrification and phosphorus starvation regulation were significantly upregulated in the mixed forests; notably, the abundance of phosphorus starvation regulation genes in the HJSs was 18.84% higher than that in the CLSs. A co-occurrence network analysis demonstrated that the proportion of positive correlation edges in the HJP nitrogen cycling network reached as high as 75.0%, and the average degree of the HJS phosphorus cycling network (2.691) surpassed that of the CLSs. The structural equation modeling further revealed that the association strength between the fungi and phosphorus cycling genes in the mixed forests increased to R² = 0.915 (p < 0.01) from R² = 0.213 in the pure forests. This mixed planting practice transforms nutrient cycling from a resource-competitive mode to a microbially synergized mode, thereby forming an efficient endogenous nutrient cycling system. This synergistic rhizosphere microbial effect is a key internal mechanism for overcoming nutrient bottlenecks and should serve as a diagnostic indicator of soil recovery in the ecological restoration of degraded pine forests. Full article

Fires are an ecological force that often mediates the balance between native and exotic plants in communities. We monitored post-fire vegetation dynamics in a Pinus pinaster plantation and adjacent grasslands 9, 15, and 18 months after the fire, evaluating structural and compositional changes through multivariate analyses. The invasive alien Acacia longifolia cover increased significantly in the plantation (p = 0.0006), while pine needle cover declined significantly (p = 0.0027), and P. pinaster cover did not change significantly over time (p = 0.063), although it showed an increasing trend towards the late stage. Both A. longifolia and pine needles were negatively associated with native species cover. Native cover remained consistently higher in continuous grasslands, with a significant Time × Site interaction. Post-fire succession in the plantation was associated with sequential abiotic and biotic filters, and the increase in A. longifolia may have contributed to reduced native recovery through competitive effects. These results suggest that fire alone may be insufficient to restore native grassland conditions within afforested systems and that early post-fire control of A. longifolia may be necessary to redirect succession. Full article

Black locust (Robinia pseudoacacia L.) has exceptional growth capacity in nutrient-poor environments and is therefore widely used for afforestation and land reclamation on degraded soils. However, drought stress can restrict sapling growth, which undermines the success of their establishment. The effect of a product containing two endophytic strains (Trichoderma afroharzianum P. Chaverri, F.B. Rocha, Degenkolb & Druzhinina TR04 and Trichoderma simmonsii P. Chaverri, F.B. Rocha, Degenkolb & Druzhinina TR05) was studied on a black locust sapling stand under severe drought in eastern Hungary. The two-year-old saplings were root-soaked before planting in sandy soil. The growth of Trichoderma-treated plants improved by late spring. Compared to the control trees, average height increased by 25.75%, and root collar diameter was 21.96% larger. Treated plants also showed 9.1% higher chlorophyll content and 11.1% Normalized Difference Vegetation Index (NDVI). The reduced intercellular CO₂ concentration, together with slightly lower stomatal conductance and increased transpiration rate, suggests tighter stomatal regulation and altered water-use dynamics under drought conditions. These responses indicate improved short-term drought acclimation rather than enhanced carbon assimilation capacity. Pre-planting inoculation with endophytic Trichoderma strains provides a sustainable method to enhance the early establishment and drought resilience of black locust, thereby increasing the efficacy of forest restoration by improving the survival of black locust on challenging degraded sites. Full article

Open-pit lignite mining causes significant environmental alterations, particularly through the removal of soil deposits and the creation of external dumps, which necessitate effective reclamation to restore landscape structures. This study evaluates the potential of using multi-temporal remote sensing data to assess the effectiveness of forest reclamation on selected external dumps of the Adamów, Bełchatów, and Turów Lignite Mines in Poland. Using Landsat imagery spanning five decades from 1976 to 2023, the study monitors vegetation development through the Normalized Difference Vegetation Index (NDVI) and the Soil-Adjusted Vegetation Index (SAVI). Reclaimed forest stands were compared against undisturbed reference forests within a 30 km buffer zone, with recovery defined as achieving 95% of the reference values. The results indicate that most studied sites reached a state of recovery, with success closely linked to the specific reclamation measures implemented and the age of the forest stands. Notably, the Adamów mine, which utilized Bender’s target species method, demonstrated rapid results, achieving high similarity to reference forests early in the analyzed period. In contrast, recovery in Bełchatów and Turów was more gradual, following trajectories influenced by pioneer and biodynamic afforestation methods. Ultimately, the study confirms that remote sensing is a highly efficient tool for monitoring extensive post-mining areas over long periods, providing a general assessment of biological restoration success. Full article

Quercus variabilis is one of the primary species for plantation regeneration across China’s warm-temperate and subtropical zones. However, its long-term monoculture leads to ecosystem instability. Soil fungi are essential for nutrient cycling and ecosystem functioning, yet their responses to oak-dominated mixed plantations remain insufficiently understood. This study investigated the soil fungal communities among Q. variabilis monoculture (QV), mixed plantations of Q. variabilis and Platycladus orientalis (PO), Q. variabilis and Pinus tabuliformis (PT), and Q. variabilis, P. orientalis and P. tabuliformis (PPQ). The results showed that PO and PPQ plantations contained significantly higher concentrations of SOC, TN, and TP compared to QV monoculture. Ascomycota and Basidiomycota were identified as the dominant fungal phyla across four plantation types, with PO exhibiting the highest relative abundance of Ascomycota (60.85%) and fungal alpha diversity. The soil fungal communities across all plantations were predominantly saprotrophic, followed by mixotrophic modes. The relative abundance of saprotrophic fungi was significantly greater in the mixed plantations, peaking in PO at 44.69%. The soil fungal communities in both PO and PPQ plantations exhibited higher network interaction density. The SOC, TN, TP, water content, zinc, and β-glucosidase activity served as key environmental drivers of fungal community composition. Overall, the mixed plantation of Q. variabilis and P. orientalis most effectively improved soil fertility, enhanced fungal diversity, and increased network complexity, suggesting its potential as a sustainable afforestation strategy for oak-dominated ecosystems in the low hilly regions of western Henan. However, these findings are based on a single sampling period, and long-term monitoring is required to confirm its sustained ecological benefits. Full article

Mangroves are important coastal wetland ecosystems with high ecological service values and strong carbon sequestration capacity, serving as a crucial barrier for coastal ecological security. However, current afforestation efforts often ignore environmental suitability differences among mangrove species, while the applicability value and ecological risks of exotic species (Laguncularia racemosa and Sonneratia apetala) for restoration remain poorly understood. Five native and two exotic mangrove species along China’s coasts were selected in this study. Using the MaxEnt model, we identified key environmental factors governing their distribution, predicted their current and future suitable habitats (under the SSP245 scenario in the 2070s), and quantified niche overlap between native and exotic mangroves. The results showed that temperature-related factors (air and sea temperature) are the core climatic drivers shaping the typical mangrove distribution, followed by sea surface salinity, with precipitation contributing little. Currently, niche overlap between native and the two exotic species is low (D.overlap: 0.129–0.340), indicating certain niche differentiation. Under the SSP245 scenario in the 2070s, except for Rhizophora stylosa, other studied species appear to experience expanded suitable habitat areas and a northward latitudinal distribution shift. Compared with Sonneratia apetala, Laguncularia racemosa exhibits a more pronounced expansion of suitable habitats in the future, with its overall suitable area second only to the native Kandelia obovata, indicating its stronger adaptive potential to climate change. Clarifying niche differentiation and constructing species-specific management frameworks may facilitate biological invasion control, mangrove restoration, and species diversity improvement. Full article

Microbial nutrient cycling in afforested mine soils may be affected by the plant litter quality. This study investigated how different tree species—Scots pine (Pinus sylvestris), silver birch (Betula pendula), European larch (Larix decidua), and black alder (Alnus glutinosa)—influence microbial carbon (C), nitrogen (N), and phosphorus (P) limitations in reclaimed sandy mine soils. We combined substrate-induced respiration (SIR) and ecoenzymatic stoichiometry (EES) to diagnose these metabolic constraints. The SIR analysis revealed a universal primary limitation by labile C across all tree species, with glucose addition stimulating respiration by 271%–333%, regardless of the soil organic carbon content. However, EES revealed distinct secondary nutrient constraints driven by species-specific litter quality. Alder stands exhibited severe P limitation, likely due to high P demand for symbiotic N-fixation and intense competition for P between trees and microbes. In contrast, birch stands showed stoichiometric homeostasis and a slight N deficiency. Coniferous species exhibited P limitation and low enzymatic activity, indicating a strategy focused on intensive nutrient acquisition under low-energy conditions associated with recalcitrant needle litter. These findings demonstrate that while energy limitation is a universal constraint in mine soils, tree species determine the nature and intensity of secondary nutrient limitations due to differences in litter stoichiometry. Full article

Globally, greenhouse gas (GHG) emissions have risen dramatically due to accelerated industrialization, excessive fossil fuel extraction, and agricultural activities, leading to global warming and ecosystem collapse. Achieving net-zero carbon emissions has therefore become a crucial global priority. Despite substantial international efforts, only a small number of countries have achieved carbon neutrality so far, with the majority aiming to do so by 2050 or 2060. Progress remains hindered by fragmented international coordination and inadequate integration of mitigation and adaptation co-benefits. However, agriculture is a major carbon emitter with significant mitigation potential. Attaining local carbon neutrality in agricultural landscapes is highly costly and strongly impacted by the spatial heterogeneity of GHG emissions and the diversity of available mitigation possibilities. This sector remains a major contributor to methane (CH₄) and nitrous oxide (N₂O) emissions, mainly through enteric fermentation and fertilizer use, and thus must be prioritized in global carbon neutrality strategies. Tactics such as improved livestock management, reduced use of synthetic fertilizers, conservation agriculture, afforestation, and renewable energy adoption can reduce emissions. These technical approaches should be supported by effective policy instruments, like carbon taxes, cap-and-trade schemes, low-carbon practice subsidies, and regulatory frameworks. Together, these measures can enable a transition toward long-term sustainability in agriculture by balancing emissions with removals through enhanced carbon sinks and credible offset mechanisms. Full article