Search Results (472)

Litter input, including aboveground and belowground plant residues such as leaves, branches, and roots, is a major pathway of carbon return to forest soils. The prevailing paradigm in forest carbon management emphasizes litter input as the primary driver of soil organic carbon (SOC) sequestration. Here, litter input refers specifically to experimental litter manipulation, including litter-addition and litter-removal treatments. Although numerous experimental studies have examined the effects of litter manipulation on SOC, several limitations remain. By synthesizing 1555 global observations, we demonstrate that climate zone, not litter manipulation per se, is the dominant moderator of SOC fraction responses. Litter addition significantly increased labile fractions (light fraction: +60%) but left MAOC largely unchanged. Conversely, litter removal depleted labile pools yet failed to destabilize MAOC. This universal inertia of MAOC challenges the assumption that litter management directly enhances long-term carbon stability. Furthermore, we reveal a critical climate dependency: tropical forests show attenuated carbon gains under litter addition, while temperate systems are more responsive. Our findings necessitate a paradigm shift from uniform litter-based strategies to climate-zone-specific forest management, prioritizing the protection of existing soil carbon in vulnerable biomes over indiscriminate litter augmentation. Full article

The alpine grassland ecosystem in the Source Region of the Yellow River (SRYR) faces the dual pressures of ecological protection and economic development. Its ecological fragility and climate sensitivity make local animal husbandry susceptible to meteorological disasters. To overcome adverse selection and moral hazard in traditional animal husbandry insurance, this study integrates 963 field sampling observation data, over 400 valid herdsmen survey data, and long-term environmental time series variables. A random forest model (R² = 0.59, RMSE = 65.84 g/m², superior to the artificial neural network in this paper) was used to estimate grass yield. Hodrick–Prescott (HP) filtering was used to separate meteorological yield per unit area and derive yield loss rate. A joint distribution model of meteorological indicators and loss rate was constructed using a Copula function to capture tail-dependent structures, providing a basis for determining trigger thresholds and actuarial pricing of pure insurance premiums. The study reveals the transmission mechanism of climate disasters to feeding costs and designs regional drought and snow disaster index insurance. The compensation standard is based on meteorological indicators falling below the trigger threshold and a yield reduction rate greater than 5%. Using 10,000 Monte Carlo simulations, the drought premium rates for zones I-IV are determined to be 2.03–6.03%, and the snow premium rates to be 2.25–5.42%, corresponding to a premium of RMB 5.21–9.61 per mu for drought and RMB 5.78–8.64 per mu for snow. This design reduces basis risk through zoning and composite triggering, providing a scientific tool for climate risk management in alpine grasslands. Full article

(1) Research Highlights: This study provides the first integrated assessment of Scots pine (Pinus sylvestris L.) growing in the urban forests of Karaganda, Kazakhstan, a city consistently ranked among the most air-polluted cities globally. We examined the adaptive phyto-chemical response of needles to extreme technogenic stress and evaluated their dual potential as biological filters and renewable sources of bioactive compounds. (2) Background and Objectives: Urban forests are critical for mitigating air pollution; however, the biochemical responses of trees in heavily industrialized environments remain poorly understood. Karaganda faces severe atmospheric pollution from mining, metallurgy, and energy sectors, with particulate matter (PM) levels exceeding permissible limits by up to 20-fold. This study aimed to evaluate the state of Pinus sylvestris, a key component of local protective plantations, by studying heavy metal accumulation, anatomical localization of secondary metabolites, and the phytochemical profile and biological activity of needle extracts obtained using different extraction techniques. (3) Materials and Methods: Needles were collected from 15 trees across three sites in Karaganda’s industrial green zones. Heavy metal content (Pb, Cd, As, and Hg) was determined using atomic absorption spectroscopy and voltammetry. Anatomical–histochemical analysis localizes major metabolite classes. Liquid extracts were prepared using four methods, percolation (PER), vortex-assisted (VAE), microwave-assisted (MAE), and ultrasound-assisted (UAE) extraction, and analyzed by GC-MS. Antimicrobial activity was tested against S. aureus, B. subtilis, E. coli, and C. albicans using the disk diffusion method. The antioxidant capacity (water- and fat-soluble) was measured amperometrically. Statistical analysis was performed using one-way ANOVA with Tukey’s HSD test (p < 0.05). Results: Despite extreme ambient pollution, heavy metal concentrations remained below pharmacopoeial limits (Pb < 0.1, Cd < 0.05, As < 0.01, Hg < 0.001 mg/kg), indicating effective biofiltration without toxic accumulation. Histochemistry confirmed the active synthesis of protective phenolics, flavonoids, and essential oils in the mesophyll, epidermis, and schizogenic cavities. GC-MS identified 72 compounds in the PER extract, 70 (the VAE), 72 in (MAE), and 46 in (UAE). The PER extract exhibited the highest relative abundance of bioactive terpenoids: α-cadinol (5.24%), α-muurolene (4.32%), and caryo-phyllene (2.20%). UAE extracts exhibited elevated 5-hydroxymethylfurfural (6.90%), indicating degradation. Antimicrobial testing revealed that PER produced the largest inhibition zone against S. aureus (15.0 ± 1.0 mm), significantly exceeding that of the other methods (p < 0.001). PER extract also demonstrated the highest water-soluble antioxidant capacity (3600 ± 0.40 mg quercetin equiv./dm³) and substantial fat-soluble activity (1633 ± 0.23 mg gallic acid equiv./dm³). (4) Conclusions: Pinus sylvestris in Karaganda exhibits remarkable adaptive resilience, maintaining safe heavy metal levels while accumulating a rich repertoire of stress-induced secondary metabolites. Classical percolation optimally preserves this native phytocomplex, yielding extracts with superior antimicrobial and antioxidant properties. These findings support a dual-use model wherein urban pine plantations simultaneously serve as living biofilters and renewable sources of standardized bioactive extracts, a concept with direct implications for circular bioeconomy strategies in industrial regions worldwide. This supports the strategic importance of coniferous plantations for bioremediation and sustainable resource use in industrial regions. Full article

Land use/cover change (LUCC) strongly regulates ecosystem carbon storage and provides a critical entry point for carbon-oriented territorial spatial governance. However, balancing carbon sequestration, food security, urban expansion, and ecological protection remains challenging in Southwest China’s Ecological Security Barrier Zone (ESBZ). In this study, we coupled the Patch-generating Land Use Simulation (PLUS) model with the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) carbon module to reconstruct LUCC and carbon-storage dynamics during 1999–2024 and to project land-use patterns and carbon storage in 2049 under four scenarios: Natural Development (NDS), Urban Development (UDS), Cultivated land Protection (CPS), and Ecological Protection (EPS). Unlike most existing PLUS–InVEST studies focused on cities, watersheds, or single provinces, this study targets a national ecological security barrier and integrates land-use evolution, carbon-storage responses, scenario trade-offs, and zoning-oriented governance into one analytical framework. It therefore provides spatially explicit evidence not only for carbon-oriented land management but also for interprovincial ecological compensation and coordinated ecological security governance in ecologically fragile regions. The 2024 land system was dominated by forest land (56.40%), cultivated land (25.47%), and grassland (16.09%). From 1999 to 2024, forest land expanded by 1.966 × 10⁴ km², whereas cultivated land and grassland decreased by 9.738 × 10³ km² and 1.874 × 10⁴ km², respectively; 92.65% of construction-land expansion originated from cultivated land conversion. Correspondingly, total carbon storage followed a “fluctuation–decline–recovery” trajectory, decreasing from 3.833 × 10¹⁰ t in 1999 to 3.820 × 10¹⁰ t in 2014, before rebounding to 3.831 × 10¹⁰ t in 2024. Pronounced provincial heterogeneity was observed: Sichuan and Yunnan jointly contributed about 76% of regional carbon storage, while Chongqing and Guizhou remained relatively low. By 2049, EPS produced the highest carbon storage (3.854 × 10¹⁰ t), whereas CPS, UDS, and NDS all led to lower values than in 2024. These contrasts indicate that the four scenarios do not represent a simple ranking of “better” or “worse”, but rather different trade-offs among carbon sinks, cultivated land protection, urban development, and regional equity. Overall, the results support province-differentiated, zoning-based land governance and highlight the need to coordinate ecological protection, cultivated-land conservation, urban growth control, and interprovincial ecological compensation to enhance carbon sequestration and safeguard ecological security in the ESBZ. Full article

Mountain forests within arid zones function as critical regional “water towers” and biodiversity hotspots, providing essential ecosystem services (ESs) such as carbon sequestration, water retention, soil conservation, and habitat maintenance. Despite their ecological significance, the spatiotemporal characteristics of these services remain insufficiently characterized. For this study, focusing on the Altai Mountains in northwestern China, we employed the InVEST model using climate, land cover, and soil survey datasets (2000–2020) to quantify ES dynamics, then applied Spearman rank correlation to analyze their spatial interactions. Results indicated the following distinct spatiotemporal patterns: (1) Temporally, water retention capacity increased by 23.5% from 2000 to 2020, with the most rapid growth occurring between 2000 and 2010, whereas carbon storage experienced a slight decline of 1.9%. (2) Spatially, water retention followed a “high-North, low-South” distribution, while carbon storage and habitat quality were highly concentrated in the central mid-elevation zones (1400–2400 m). (3) Trade-off intensification: a significant negative correlation between water retention and carbon storage deepened over the study period, highlighting an escalating “water–carbon” conflict. The aforementioned findings suggest that future management should be focused on avoiding high-density afforestation in mid-elevation water-sensitive zones to prevent excessive evapotranspiration. Instead, spatially differentiated strategies—prioritizing water yield protection in high-altitude regions and stand structure optimization in mid-altitude forests—are essential for reconciling regional ecosystem service trade-offs. Full article

Ground-dwelling pheasants are vital indicators of forest ecosystem health. Understanding their distribution and response to climate change is crucial for regional biodiversity conservation. Based on 97,000 camera-days of infrared monitoring from 2019 to 2022 in Huzhou, China, we analyzed the spatial patterns and niche overlap of five pheasant species, including the first class national protected animal Elliot’s Pheasant (Syrmaticus ellioti), using MaxEnt modeling and Schoener’s D index. Results showed the following: (1) Pheasants in Huzhou exhibited distinct vertical gradients, with Elliot’s Pheasant restricted primarily to mid-mountain forests (200–600 m) in western Anji. (2) Iso-thermality and winter thermal limits were the primary drivers of its distribution. (3) Niche analysis revealed intense competitive pressure; Elliot’s Pheasant habitat was largely encompassed by dominant species like the Silver Pheasant (Lophura nycthemera), showing a high overlap (D = 0.642) with the Koklass Pheasant (Pucrasia macrolopha). (4) By 2050, its suitable habitat is projected to shrink by 84.6% (from 1085.7 to 118.8 km²) and shift eastward. These findings highlight the high climate sensitivity and competitive vulnerability of Elliot’s Pheasant. We recommend prioritizing micro-habitat maintenance in mid-mountain zones and proactively establishing ecological corridors between Anji and Deqing to mitigate habitat loss and displacement. Full article

By integrating multi-source data, this study systematically analyzes the evolution of land use structure, spatiotemporal differentiation characteristics of Ecosystem Service Value (ESV), and core driving mechanisms in the Huaihe River Ecological Economic Belt (HREEB) in eastern China from 2000 to 2020, based on the ESV equivalent accounting model and XGBoost-SHAP coupled framework. The main results are as follows: (1) The land use structure is dominated by cropland, construction land, and forest land. Over the 20-year period, cropland was continuously converted out, primarily transforming into construction land and forest land, while other land types remained relatively stable. (2) Temporally, the total ESV showed a fluctuating downward trend, first increasing and then decreasing from 2000 to 2020. Spatially, the ESV exhibited a corridor effect of “decreasing from the river channel center to both banks”. High-value areas were concentrated in the eastern river–sea linkage zone and the central-western inland rising zone, while extremely low-value areas in 2020 were located in the northern Huaihai Economic Zone (with dense construction land), indicating an overall medium service level. (3) The evolution of ESV was driven by both natural and human factors: among natural factors, water coverage, elevation, and slope had positive effects, while high temperature had an inhibitory effect; among human–economic factors, population density showed an “increase first and then decrease” effect, and urban expansion significantly weakened ESV in the later period. The spatial differentiation presented a pattern of “natural background support in the upper reaches and socioeconomic intervention in the lower reaches”. This study provides a scientific basis for the optimization of territorial space and ecological protection and restoration in the Huaihe River Ecological Economic Belt, and also offers a replicable research paradigm for ecosystem service management in similar river basin-type regions. Full article

Balancing tourism development with ecological integrity remains a central challenge in the management of protected areas. This study proposes a spatial framework that integrates the Outdoor Recreation Suitability Index (ORSI) and the Landscape Ecological Risk Index (ERI) to identify and optimize low-impact recreation corridors within Giant Panda National Park, China. Recreation suitability and ecological risk were modeled using environmental variables and landscape metrics, respectively. The results reveal a clear spatial pattern: high-suitability zones are concentrated in the central and northeastern areas, characterized by gentle terrain and extensive forest cover, while ecological risk is elevated in fragmented, human-disturbed peripheral regions. Although ORSI and ERI exhibit an overall negative spatial correlation, bivariate analysis reveals localized mismatches—areas where high recreation potential coincides with ecological vulnerability—indicating potential conflict zones. These zones are typically located along transitional park boundaries where accessibility intersects with ecological sensitivity. To mitigate such conflicts, a least-cost path analysis was conducted based on a composite resistance surface combining ORSI and inverted ERI values. The resulting corridor network connects 40 core areas while effectively avoiding ecological hotspots. Corridor buffers are predominantly composed of forest and shrubland, suggesting high environmental compatibility, particularly in the Qinling region. By translating spatial trade-offs into practical corridor design, this study provides a replicable approach for harmonizing recreation planning with conservation objectives. The proposed framework offers actionable guidance for evidence-based zoning, visitor flow management, and adaptive tourism development in ecologically sensitive protected landscapes. Full article

Coastal provinces in eastern China are experiencing rapid urbanization that challenges ecosystem services and low-carbon development. In this study, Zhejiang, Fujian, and Guangdong Provinces were selected, and the influence of land use/land cover change (LUCC) on carbon storage and its spatial heterogeneity was quantified. LUCC datasets for 2000, 2005, 2010, 2015, and 2020 were compiled to describe land-use dynamics over 2000–2020. Carbon storage was estimated with the InVEST model. Land-use patterns for 2035 were simulated using the PLUS model under three scenarios: natural development, ecological protection, and development priority. Spatial autocorrelation analysis and multiscale geographically weighted regression (MGWR) were then used to determine the key drivers of spatial variability in carbon storage. Between 2000 and 2020, farmland, forest, grassland, and unused land showed an overall decline, while water bodies and tt-up land expanded; together, these changes corresponded to a carbon-storage loss of 121.19 Tg. Carbon density exhibited pronounced spatial clustering, with higher values concentrated in mountainous and less urbanized areas; built-up expansion and forest degradation were the primary contributors to carbon loss. By 2035, total carbon storage is projected to decrease by 74.67 Tg under natural development and by 108.54 Tg under development priority, whereas ecological protection is projected to yield the smallest decline (35.71 Tg). These results underscore the importance of sustainable coastal land-use planning and integrated coastal zone management, which balance development and ecosystem services by prioritizing ecological protection, curbing built-up expansion, and promoting forest restoration. Such nature-based solutions can enhance carbon sequestration, strengthen climate resilience, and support China’s low-carbon transition toward its dual-carbon targets. Full article

Highway construction is a major driver of landscape transformation, yet its integrated effects on ecological functions in forested regions under strong ecological governance remain poorly quantified. This study examines spatiotemporal changes in land use, landscape patterns, ecosystem service value (ESV), and habitat connectivity within 1–5 km buffer zones along three highways in Zhejiang, China, from 2000 to 2023. Results indicate that highway-induced fragmentation was land-use-specific: cropland and construction land became more fragmented, while forests maintained high spatial cohesion due to protective policies. ESV per hectare increased over time and with distance from highways, driven by forest expansion and economic revaluation. In contrast, habitat connectivity for reptiles, amphibians, mammals, and birds declined, revealing a decoupling between ESV enhancement and connectivity conservation. These findings underscore the context-dependent impacts of highways and highlight the need for integrated management strategies that preserve forest integrity to balance ecological functions in rapidly developing regions. Full article

The intensifying conflict between urban–rural development and the natural environment under rapid industrialization and urbanization underscores the necessity to balance ecological preservation with economic growth for sustainable land use. Grounded in the Production–Living–Ecological Space (PLES) theory, this study classifies land use into production, living and ecological functional types to set three scenarios (natural development, production–living priority, ecological priority), and employs the PLUS model with a land use conversion cost matrix and spatial driving factors as input variables to simulate land use changes and their ecological impacts. Analysis of the period 2010–2020 reveals an initial decline followed by a recovery in ecological quality, highlighting the urgency of improved spatial planning. Projections for 2025–2035 based on the PLES theory reveal divergent trajectories across three scenarios simulated by the PLUS model, whereas the production–living priority scenario accelerates urban–industrial expansion and exacerbates environmental degradation by driving irrational land use conversion. In contrast, the ecological priority scenario significantly enhances ecological and environmental quality while minimizing the loss of agricultural land, achieving a more sustainable balance between development and conservation. Through quantitative calculation of the ecological contribution rate of land use transitions, the internal conversion of agricultural production space contributes the most to regional ecological quality improvement (42.50% in 2025–2030 in the ecological priority scenario), and forest PLES land use category has the highest ecological environment index (0.2836 in 2025) among all PLES types, emphasizing the pivotal role of agricultural production space and the high ecological value of forestland in regional ecosystems. These findings demonstrate that prioritizing ecological strategies is essential for realizing a win–win outcome between ecological protection and economic development, offering actionable insights for sustainable land use planning in ecologically fragile transition zones similar to the Southern Taihang region. Full article

Vegetation in Northeast China has undergone complex changes under the dual pressures of climate change and human activities. Quantifying long-term vegetation dynamics and identifying their key drivers are critical for regional sustainability, ecological engineering construction, and environmental conservation. Ecological restoration plays a pivotal role in vegetation protection and recovery in this region; however, it has often been overlooked as a core driver in previous studies. This study analyzed the spatiotemporal dynamics of vegetation in Northeast China based on the long-term satellite-based leaf area index (LAI) datasets from 2000 to 2020, investigated the factors driving the spatiotemporal variation in LAI, and quantified the respective contributions of climate change and human activities to its change. The results showed that: (1) The LAI in Northeast China increased at a rate of 0.0292 yr⁻¹ since 2000, with 80.8% of the region showing vegetation improvement, predominantly within ecological restoration zones; however, urbanization induced severe local vegetation degradation. The Natural Forest Conservation Program (NFCP) exhibited the highest LAI growth rate (0.0315 yr⁻¹), followed by the Shelterbelt Program for Liaohe River (SPLR) and the Three-North Shelterbelt Program (TNSP) (0.0313 yr⁻¹ and 0.0294 yr⁻¹, respectively). (2) Land use type, soil type, and evapotranspiration were the primary single drivers of LAI spatial heterogeneity, and the interaction between land use and soil types has the most significant impact on it. (3) Climate change and human activities jointly accounted for 78.4% of the LAI variations across the study area, with the relative contribution of human activities (C_HA = 68.9%) being significantly higher than that of climate change (C_CC = 31.1%). In the vegetation browning regions of the three ecological restoration zones, the contribution of human activities exceeded 60%. In contrast, the dominant drivers of vegetation greening varied substantially among the zones: greening in the TNSP and SPLR was primarily regulated by climate change (C_CC > 50%), whereas in the NFCP it was mainly driven by human activities. This study highlights the key role of human activities (especially ecological restoration programs) in the improvement of vegetation cover in Northeast China, which can help to assess the benefits of ecological restoration in Northeast China, provide references for ecological and environmental management policy formulation, and promote the construction of regional ecological civilization. Full article

Under strict ecological protection regimes, identifying development pathways that can be integrated into forest governance without undermining conservation boundaries remains a critical challenge. This study adopts a qualitative case-study approach to examine how forest birdwatching is governed as a form of low-disturbance forest use in Mingxi County, China. Based on semi-structured interviews, field observations, and governance-related materials, the analysis examines governance mechanisms and interaction processes shaping everyday regulatory practices. The findings indicate that forest birdwatching does not function as low-disturbance use by virtue of its activity type alone, but through its progressive embedding within routine forest governance under rigid institutional constraints. Institutional enforcement, spatial zoning, community-based benefit coordination, and media-supported normative regulation interact to stabilize behavioral boundaries, manage participation, and mitigate disturbance risks. The governance significance of forest birdwatching lies not in its direct replicability across regions, but in its value as an analytical reference for understanding how governance elements may be conditionally configured under specific institutional, organizational, and spatial contexts. By clarifying the minimum enabling conditions under which low-disturbance forest use can contribute to collaborative governance outcomes, this study provides a context-sensitive analytical framework for forest governance in ecologically valuable but development-constrained regions. Full article

As a significant component of hydraulic cultural heritage within the Grand Canal Cultural Belt, ancient stone bridges serve as vital physical evidence reflecting the evolutionary patterns of water conservancy and settlement spaces in Wuxi. Consequently, understanding their distribution holds critical significance for the holistic protection and revitalized utilization of the heritage. This study investigates 118 ancient stone bridges in Wuxi, China, employing ArcGIS spatial analysis methods, specifically average nearest neighbor, kernel density estimation, and standard deviational ellipse, to examine spatiotemporal characteristics. Additionally, a random forest (RF) model is utilized to quantify the importance of natural environmental factors influencing their distribution. The results reveal the following: (1) Temporally, the distribution transitioned from a random pattern in the Song Dynasty to a highly clustered pattern during the Ming, Qing, and Republic of China periods. (2) Spatially, the distribution centroid exhibited a distinct southwestward trend, evolving from a dispersed structure into a multi nuclei aggregation model centered on Yixing and Wuxi City. (3) Environmentally, bridges are predominantly located in low-elevation plains, gentle slopes (2° to 5°), and stable zones far from geological hazards. They exhibit a preference for northeast and northwest aspects, with the highest concentration within 100 m of rivers and in paddy or yellow–brown soil regions. (4) The RF model identifies rivers as the absolute dominant factor, followed by aspect, geological hazards, slope, and elevation, while soil factors have the lowest importance. These findings enrich the conservation theory for hydraulic cultural heritage and provide a scientific basis for the risk assessment, hierarchical protection, and integrated tourism planning of ancient stone bridges. Full article

Riparian forests play a critical role in protecting soil and water resources and maintaining ecosystem stability. In this study, we evaluated the response of soil chemical and microbial attributes to different stages of riparian forest restoration in the protection zone of the Itaipu Reservoir (Brazil). Soil samples were collected during summer and winter from sites representing four restoration stages (initial, 3, 19, and 30 years), as well as from an adjacent agricultural field and a native forest used as reference systems. We assessed soil chemical properties, microbial biomass carbon, basal respiration, enzymatic activities, and the soil microbial community structure using 16S rRNA gene sequencing. Principal component analysis (PCA) revealed a clear restoration gradient, with older restored sites progressively converging toward the native forest condition. Soil chemical properties showed gradual recovery along the restoration trajectory, with increases in soil organic carbon, cation exchange capacity, and base saturation. In contrast, the availability of P, K, Ca, and Mg declined at early restoration stages and increased with restoration age. Microbial biomass carbon increased by approximately 60% from early restoration to native forest conditions, while metabolic quotients (qCO₂) decreased, indicating greater microbial efficiency and reduced metabolic stress. Enzyme activities related to C, P, and S cycling increased by 1.5- to 3-fold with restoration age. Sequencing analyses indicated a progressive convergence of microbial community composition toward that of the native forest, driven by shifts in relative abundance and the enrichment of forest-associated taxa, such as Verrucomicrobia and Acidobacteria, at advanced restoration stages. Overall, long-term riparian forest restoration promoted substantial recovery of soil chemical fertility and microbial community structure and functioning, reinforcing the role of soil microbiota as a sensitive indicator of ecosystem resilience and restoration success. Full article