Vegetation Patterns Research Articles

Adult Dietary Patterns and Their Association With Iodine Nutrition Levels and Thyroid Function: A Cross-Sectional Study.

To understand the dietary patterns of adults and explore their association with iodine nutritional levels and thyroid function in adults. We randomly collected 5 ml of adult urine samples and measured urinary iodine concentration by cerium arsenate-catalyzed spectrophotometry. A serum sample of 5 ml was collected for the determination of free triiodothyronine (FT3), free thyroxine (FT4) and thyrotropin (TSH), and diet-related information was collected through a food frequency questionnaire. Dietary patterns were extracted by principal component analysis and the relationship between dietary patterns and iodine nutrition levels and thyroid function was explored. A cross-sectional study involving adults in Xinjiang, China was conducted. A total of 435 adults were enrolled in the study. The overall median urinary iodine of the 435 respondents was 219.73 μg/L.The dietary patterns were PCA1 (staple food pattern), PCA2 (fruit, vegetable, and meat pattern), PCA3 (fish, shrimp, and legume pattern), and PCA4 (Dairy-based protein pattern). The correlation analyses showed that PCA1 and PCA3 were positively correlated with the urinary iodine concentration (UIC). The results of the multivariable analysis showed that PCA1, Q1, Q2, and Q3 were associated with an increased risk of iodine deficiency compared with Q4 [ (OR): 260.41 (95%CI: 20.16, 663.70)], 59.89 (5.64, 335.81), and 2.01 (0.15, 26.16), respectively]. In PCA2, Q3 was associated with an increased risk of iodine deficiency compared with Q4 [OR: 0.16 (0.05, 0.53)]. In PCA3, Q3 was associated with an increased risk of iodine deficiency compared with Q4 [OR: 0.23 (0.06, 0.90)]. In PCA4, Q1 was associated with an increased risk of iodine deficiency compared with Q4 [OR: 31.30 (4.88, 200.64)]. This study demonstrated that of the four dietary patterns, the least dependent staple food pattern (Q1) had a higher risk of iodine deficiency compared to the most dependent staple food pattern (Q4). However, the current evidence on the effect of dietary patterns on thyroid function needs to be validated by further longitudinal studies that include long-term follow-up, larger sample sizes, and repeated measures.

Challenges and Strategies in Elephant Conservation: A Comprehensive Review of Land Use Impact and Management Approaches in Dalma Wildlife Sanctuary, India

Abstract The Dalma Wildlife Sanctuary, a critical habitat for elephant conservation in the Dalma Landscape, is increasingly experiencing the multifaceted impacts of climate change. This study reviews secondary literature to examine the consequences of Land Use and Land Cover (LULC) changes on elephant populations, emphasizing the exacerbating effects of climate-induced alterations. The sanctuary faces challenges like habitat degradation and fragmentation, which impede wildlife movement and intensify human-wildlife conflicts, particularly with elephants. These issues are now compounded by climate change, which is altering vegetation patterns, water availability, and seasonal behaviours of wildlife, further straining the delicate balance of this ecosystem. This paper methodically dissects the literature, highlighting how climate change interplays with existing environmental stressors, affecting the conservation strategies and viability of elephant corridors. The review also considers management strategies, underscoring the need for adaptive measures that address the dual challenges of habitat degradation and climate change. By broadening the scope to include the climate change dimension, this research not only underscores the researcher’s comprehensive understanding of the sanctuary’s ecological challenges but also aligns the study with global environmental concerns, making it relevant in the context of contemporary wildlife conservation efforts. Through a structured approach, the paper is divided into sections that explore the sanctuary’s ecological significance, the factors impacting elephant populations with a focus on climate change, and methods for studying human-elephant conflicts in the context of a changing climate. This comprehensive analysis aims to identify research gaps, propose adaptive conservation strategies, and contribute to the broader understanding of how climate change is reshaping wildlife conservation paradigms.

Forest Breeze - Cold Pool Interactions Drive Convective Organization over Heterogeneous Vegetation

Abstract Heterogeneous landscapes can influence the development of convection through the generation of thermally-driven mesoscale circulations. To assess the impacts of these circulations and their interaction with sea breezes, we simulated convection in an idealized coastal environment using the Regional Atmospheric Modeling System (RAMS). We compared simulations with striped patterns of surface vegetation to those of uniform vegetation to identify the importance of vegetation heterogeneity in impacting convective development. Under dry soil conditions representative of those during the TRACER and ESCAPE campaigns in June 2022, we found that these vegetation-induced circulations, referred to in literature as “forest breezes,” are more important than the sea breeze in determining the location of convection initiation. Convection and precipitation are also found to be favored over forests and suppressed over pasture and suburban landscapes as a result of greater surface sensible heat flux over the forest. Our findings also indicate that forest breezes are important for initiating convection along the boundaries of the forest, but that cold pools may play a key role in propagating the forest breezes toward the center of the forest stripe. In our simulations, the collisions of these breezes in the center of the forest stripe leads to uplift and strong convection there; however, a different width of the forest stripe would alter when the forest breezes collide, or whether they collide at all. The presence of these cold pools may therefore impact the “ideal stripe width”, the width of each vegetation stripe which maximizes domain-wide precipitation.

Modern Pollen–Vegetation Relationships: A View from the Larch Forests of Central Siberia

Understanding how pollen assemblages represent the local and regional vegetation composition is crucial for palaeoecological research. Here, we analyze 102 surface moss/soil pollen samples collected from four study regions located in various boreal forest vegetation types in Central Siberia. Despite Larix being the most prevalent tree generus in the study area, the proportion of Larix pollen can be as low as 0.6–1.5% (0.4–4.7% on average) even in localities with a high canopy density of the species. No relationship between the quantity of Larix pollen in the spectra and the abundance of Larix in the local vegetation was found. The dominant components of the pollen assemblages are Betula and Alnus fruticosa. The pollen value of Picea is low (2.6–8.2% on average), with higher proportions at sample plots where spruce is abundant in forests. Pinus is a highly prevalent pollen species within its geographical range, comprising up to 40% of pollen assemblages. Outside of the range, the ratio of Pinus pollen was higher in habitats with low canopy density and in treeless ecosystems. The composition of herbaceous pollen and spores is significantly affected by the local plant community, offering more comprehensive insights into past vegetation patterns.

Impact of Microtopography and Neighborhood Effects on Individual Survival Across Life History Stages.

Understanding drivers of plant community assembly and individual survival in forest ecosystems is crucial for effective conservation and management. While macro-scale factors influencing vegetation patterns are well documented, the combined impact of microtopographic variations and neighborhood effects at neighborhood scales, particularly in subtropical forests, requires further study. To contribute to this area of research, we established a 9.6 ha dynamic plot in a subtropical evergreen broad-leaved forest to examine the interplay between microtopographic factors and neighborhood effects on individual plant survival across different life stages. We conducted a comprehensive analysis of microtopographic variables and neighborhood effects, with individual plant survival censused through repeated surveys at 5-year intervals. Mixed-effects models were employed to assess the combined influence of these factors across life stages. Our results reveal that both microtopographic factors and neighborhood effects significantly influence plant survival, with their impacts varying across life stages. Water availability, represented by flow direction, emerged as a consistently critical factor throughout all life stages. Elevation and the topographic position index showed significant positive effects on survival, particularly in later life stages, possibly reflecting adaptations to light acquisition and water drainage. The influence of topographic factors intensified with succession, while the impact of neighborhood effects, particularly asymmetric competition and conspecific negative density dependence, changed as plants matured. This study enhances our understanding of forest community assembly, emphasizing the importance of considering abiotic and biotic factors across multiple scales for effective forest conservation and management. It provides insights into mechanisms driving spatial variation in community composition, crucial for preserving biodiversity in heterogeneous forest landscapes.

Determination of Forest Health using Remote Sensing Techniques in Gashaka-Gumti National Park, Northeast, Nigeria

This study was conducted in order to determine the health status of forest vegetation in Gashaka-Gumti National Park. Landsat images were downloaded from the USGS website. The images were pre-processed using radiometric correction since the reflectance values were needed for computing spectral indices, the digital numbers were converted to radiance and reflectance, and analysis was carried out using a raster calculator. The range of NDVI, GNDVI, ARVI and MSI were used for health assessment. Utilizing NDVI, GNDVI, ARVI, and MSI as assessment tools revealed moderate to good health in most forest regions, with higher ARVI, GNDVI, and NDVI indicating healthier vegetation and elevated MSI values suggesting areas under moisture stress. the average values of NDVI, GNDVI, ARVI, and MSI over three decades indicate a potential decline in overall vegetation health, reduced green vegetation, changes in vegetation conditions, and a decrease in moisture stress, suggesting a potential increase in greening and photosynthetic activities in plants. These trends highlight the dynamic nature of the forest ecosystem over the studied period. Positive correlations between ARVI, GNDVI, and NDVI across years indicate a consistent vegetation pattern, while negative correlations with MSI suggest potential inverse relationships, providing valuable insights into forest health dynamics. Higher values of ARVI, GNDVI, and NDVI generally signify healthier vegetation, whereas elevated MSI values may indicate areas experiencing moisture stress, emphasizing the importance of monitoring these indices for sustainable forest management. The study recommends the sustained use of NDVI, GNDVI, ARVI, and MSI for forest health monitoring in the study area, implementing integrated pest management based on identified stress conditions, utilize spatial maps for strategic timber harvest planning, developing climate-resilient management considering moisture stress, and invest in research for enhanced assessment precision and understanding of ecosystem dynamics.

Using Paleoecological Methods to Study Long-Term Disturbance Patterns in High-Elevation Whitebark Pine Ecosystems

Pinus albicaulis (whitebark pine) is a keystone species, providing food and habitat to wildlife, in high-elevation ecological communities. In recent years, this important species has been negatively impacted by changes in fire regimes, increased Dendroctonus ponderosae (mountain pine beetle) outbreaks associated with human landscape and climate modification, and the continued impact of the non-native Cronartium ribicola (white pine blister rust). This research investigates changes in fire occurrence, the establishment of Pinus albicaulis, and fuel availability at a high-elevation site in the Sawtooth National Recreation Area, Idaho, USA. Charcoal and pollen analyses were used to reconstruct fire and vegetation patterns for Phyllis Lake, Idaho, USA, over the past ~8200 cal y BP. We found that significant fire episodes occurred when the pollen accumulation rates (PARs) indicated more arboreal fuel availability, and we identified that Pinus albicaulis became well established at the site ~7200 cal y BP. The high-elevation nature of Phyllis Lake (2800 m) makes this record unique, as there are not many paleorecords at this high elevation from the Northern Rocky Mountains, USA. Additional high-elevation sites in Pinus albicaulis habitats will provide critical insight into the long-term dynamics of this threatened species.

Vegetation changes of Lushan, China between 1959 and 2020 based on pollen data

Both climatic change and human activity are currently driving the dynamic of vegetation, which may vary from region to region. On Lushan, located in the eastern China, the subtropical secondary forests during the natural succession endure the pressure from ongoing climate warming on the one hand. They are influenced by anthropogenic disturbance on the other hand for recent decades. Previously, palynological research has discovered that the pollen assemblages from surface soil sample on Lushan can basically reflect the characteristics of local vegetation. Here, we did a comparative study by using the pollen analysis to investigate the vegetation changes of Lushan from 1959 to 2020. We compared the composition of pollen assemblages obtained in 1959 with that in 2020 along different altitudes. Further, the biomisation method was employed to discover the changes of different vegetation types, which were reflected by the pollen-based reconstructed biomes. Meanwhile, the temporal beta diversity analysis was used to extract the sites experienced the significant vegetation shift and the most important taxa change. Results showed that the pollen composition over the past 60 years on Lushan had altered remarkably. The vegetation shifted at all altitudes. The current vegetation pattern of Lushan: evergreen broadleaved forest in low elevation, temperate deciduous broadleaved forest in middle elevation and cool mixed forest in high elevation, is the successional consequence of the past 60 years. The forces driving the vegetation dynamics might be from multiple sources. However, the human disturbance seems to play quite an important role during forest succession. Our study is potentially useful both for paleoecological reconstructions and wider understanding of current climate change that are relevant to subtropical forests of Asia.

Novel Approach in Vegetation Detection Using Multi-Scale Convolutional Neural Network

Vegetation segmentation plays a crucial role in accurately monitoring and analyzing vegetation cover, growth patterns, and changes over time, which in turn contributes to environmental studies, land management, and assessing the impact of climate change. This study explores the potential of a multi-scale convolutional neural network (MSCNN) design for object classification, specifically focusing on vegetation detection. The MSCNN is designed to integrate multi-scale feature extraction and attention mechanisms, enabling the model to capture both fine and coarse vegetation patterns effectively. Moreover, the MSCNN architecture integrates multiple convolutional layers with varying kernel sizes (3 × 3, 5 × 5, and 7 × 7), enabling the model to extract features at different scales, which is vital for identifying diverse vegetation patterns across various landscapes. Vegetation detection is demonstrated using three diverse datasets: the CamVid dataset, the FloodNet dataset, and the multispectral RIT-18 dataset. These datasets present a range of challenges, including variations in illumination, the presence of shadows, occlusion, scale differences, and cluttered backgrounds, which are common in real-world scenarios. The MSCNN architecture allows for the integration of information from multiple scales, facilitating the detection of diverse vegetation types under varying conditions. The performance of the proposed MSCNN method is rigorously evaluated and compared against state-of-the-art techniques in the field. Comprehensive experiments showcase the effectiveness of the approach, highlighting its robustness in accurately segmenting and classifying vegetation even in complex environments. The results indicate that the MSCNN design significantly outperforms traditional methods, achieving a remarkable global accuracy and boundary F1 score (BF score) of up to 98%. This superior performance underscores the MSCNN’s capability to enhance vegetation detection in imagery, making it a promising tool for applications in environmental monitoring and land use management.

Morphological and Physiological Characteristics Influencing CO2 Assimilation Rate and Growth in Different Half-Sib Families of Quercus acuta and Q. glauca

Climate change alters vegetation patterns, pushing subtropical forests further north. These forests play a crucial role for carbon neutrality efforts due to their significant CO2 assimilation potential. This study investigated CO2 assimilation rate along with growth, morphological, and physiological traits in 23 half-sib families of Quercus acuta and 26 half-sib families of Q. glauca, two prominent East Asian evergreen broadleaf species. Q. acuta exhibited significantly higher growth rates, with diameter at breast height (DBH) and aboveground biomass exceeding those for Q. glauca by 12.1% and 69.9%, respectively (p < 0.001). Leaf traits, including leaf mass pear area (LMA), leaf nitrogen, and chlorophyll content, were also greater in Q. acuta, showing 24.5%, 45.8%, and 15.6% higher values (p < 0.001). While photosynthetic traits were similar, Q. acuta exhibited a 12.7% higher intrinsic water-use efficiency (iWUE) (p < 0.01). Among half-sib families, marginal differences were observed in growth traits (p < 0.1), and significant differences in leaf morphology and physiological traits (p < 0.05) were observed. A positive correlation was found between growth and physiological traits associated with the CO2 assimilation rate in Q. acuta, but not in Q. glauca. These findings highlight the potential of Q. acuta and Q. glauca for supporting future carbon neutrality efforts and provide traits supporting carbon uptake, valuable for selecting tree species with enhanced carbon sequestration potential.

Temporal and spatial patterns of riparian vegetation in the Colastiné Basin (Argentina) and riparian ecological quality estimation as tools for water management

ABSTRACT Information on the riverbanks can improve our ability to monitor water quality and generate adequate management strategies. This research seeks insights into the riverbanks of eight Colastiné River Basin (Argentina) streams, which have been influenced by intensive agricultural land use for decades. We aim to (a) describe the temporal and spatial distribution patterns of riparian vegetation, (b) assess their current riparian quality through riverbank quality indices, and (c) estimate whether the riparian quality is linked to the water quality. Results of the Normalized Difference Vegetation Index (NDVI) showed an increasing trend in the vegetation cover with seasonal periodicities during the last 22 years in only 2 streams. Overall, 41% of plant species registered were exotic although native species dominated in most streams. The overall riverbank quality, based on the mean values of four riverbank quality indexes, was regular-to-bad. The overall water quality of the streams was low and significantly correlated to the Riparian Quality Index, suggesting a link between both compartments. More studies are needed to determine the main variables that establish this connection. Further effort is also needed to generate appropriate indices for this region, as no current ones are still developed.

Effects of climate variability and urbanization on spatiotemporal patterns of vegetation in the middle and lower Yangtze River Basin, China.

Vegetation serves as a crucial indicator of ecological environment and plays a vital role in preserving ecosystem stability. However, as urbanization escalates rapidly, natural vegetation landscapes are undergoing continuous transformation. Paradoxically, vegetation is pivotal in mitigating the ecological and environmental challenges posed by urban sprawl. The middle and lower Yangtze River Basin (MLYRB) in China, particularly its economically thriving lower reaches, has witnessed a surge in urbanization. Consequently, this study explored the spatiotemporal variations of normalized difference vegetation index (NDVI) in the MLYRB, with an emphasis on elucidating the impact of climate change and urbanization on vegetation dynamics. The results indicate that a significant increasing trend in NDVI across the MLYRB from 2000 to 2020, a pattern that is expected to persist. An improvement in vegetation was observed in 94.12% of the prefecture-level cities in the study area, predominantly in the western and southern regions. Temperature and wind speed stand out as dominant contributors to this improvement. Nevertheless, significant vegetation degradation was detected in some highly urbanized cities in the central and eastern parts of the study area, mainly attributed to the negative effects of escalating urbanization. Interestingly, a positive correlation between NDVI and the urbanization rate was observed, which may be largely related to proactive ecological preservation policies. Additionally, global climatic oscillations were identified as a key force driving periodic NDVI variations. These findings hold significant importance in promoting harmonious urbanization and ecological preservation, thereby providing invaluable insights for future urban ecological planning efforts.

Colonial management drives ecological change following the exclusion of Indigenous stewardship in a Stoney Iyethka montane grassland, Canadian Rocky Mountains

Abstract For millennia, Indigenous Peoples and their ecological stewardship have kept culturally important landscapes open, diverse and productive. Under colonization which suppresses stewardship activities, landscape vegetation patterns shift and areas previously stewarded by Indigenous Peoples are now undergoing successional change. As a case study, we document ecological change on the homelands of the Stoney Iyethka Nations in the Canadian Rocky Mountains, where landscapes have changed dramatically over the past century of colonial management. On the Stoney Iyethka traditional montane Egnuck Wida grasslands, we analysed vegetation change on both the landscape and plot level. Using oblique photographs taken in 1924 paired with 2021 satellite imagery, we compared past and present landscape vegetation cover and assessed drivers of succession. We also examined differences in vegetation class cover and plant community structure between surveys conducted in 1981, 1995 and 2020. Nearly half (47%) of the landscape surveyed showed seral progression in vegetation class, which was not explained by topography, geology or climate warming. Grassland area decreased four‐fold between 1924 and 2021. Grassland retention was strongly related to management zoning, with greater losses in the crown‐managed ecological reserve than on lands that remain under Stoney Iyethka stewardship. Vegetation plots surveyed reveal changes to plant community composition and shifts in dominant vegetation class. In plots previously composed primarily of forbs and graminoids, shrubs have become the dominant groundcover. Declines in historic vegetation include a loss of culturally important food, medicine and ceremonial plants to the Stoney Iyethka Nations. The most likely explanation for these results is the displacement of Indigenous Peoples and their stewardship from the landscape. We demonstrate that the past century of colonial environmental management has altered ecological processes maintained on this landscape for millennia by Indigenous Peoples. Read the free Plain Language Summary for this article on the Journal blog.

Diel Greenhouse Gas Emissions Demonstrate a Strong Response to Vegetation Patch Types in a Freshwater Wetland

AbstractWetland methane (CH4) fluxes are highly variable over spatial and temporal scales due to variations in CH4 production, oxidation, and transport. While some aspects of temporal variability in CH4 fluxes are well documented, diel variability is poorly constrained, and studies report conflicting findings, making it difficult to generalize. Topographic, geochemical, hydroclimatic, and vegetative variability can result in characteristically different “patches” that likely influence differences in diel patterns. We investigated diel patterns of CH4 fluxes from a large seasonal‐mineral soil wetland in Maryland (USA) across three functionally unique patches: two with vegetation (emergent and submerged aquatic vegetation) and one without (open water) during the summer of 2021. To explore the relationships between vegetation, environmental conditions, and flux patterns, we also measured physiochemical variables (air and water temperature, pH, relative humidity, PAR, dissolved oxygen, and water depth). To our knowledge, this is the first study comparing diel variability using chambers across such distinct vegetation patch types. We found that diel patterns were strongly linked to patch types: CH4 fluxes from the emergent vegetation did not display a consistent diel pattern, while fluxes from the submerged vegetation and no vegetation patches frequently peaked at 13:00 and 05:00, respectively. These differences could be a direct result of vegetation impact on production, oxidation, and/or transport of CH4 or on conditions covarying with patch type. This study contributes to the growing understanding of how CH4 fluxes vary spatially over diel cycles and emphasizes the importance of considering spatially varying diel patterns when estimating fluxes.

Vegetation restoration strategies in arid or semi-arid regions-From the perspective of optimal control.

Inappropriate human activities contribute to the degradation of ecosystems in arid or semi-arid regions. Therefore, emphasizing the importance of strategies for restoring vegetation in these areas cannot be overstated. However, there has been insufficient research on how to develop effective restoration strategies at minimal cost. This paper addresses this gap by studying how optimizing the spatiotemporal distribution of human activities through local and boundary controls can reduce the level of desertification in vegetation pattern structures, thereby facilitating the recovery of arid land vegetation. The results indicate that vegetation restoration depends on the proportion and number of human activity areas, with a trade-off between them. Furthermore, consistent conclusions were obtained on circular regions, demonstrating the robustness of the approach to boundary shapes. This paper aims to offer new insights into the restoration of arid land vegetation and the prevention of catastrophic ecosystem changes from the perspective of optimal control.

Topological differentiation of vegetation of the Lublin-Volyn geobotanical district

The position of the Lublin and Volyn (Volhynian) uplands within the geobotanical zonation system is ambiguous and disputable. An analysis of the syntaxonomical diversity and landscape distribution of the egetation of the Lublin and Volyn uplands revealed their similarity, and we consider this whole territory as the Lublin-Volyn geobotanical district of hornbeam-oak, oak forests, and steppe meadows. This district differs from the adjacent territories and is classified within the Central European mixed forests ecoregion. Typical and diagnostic syntaxa have been identified, and ecological-coenotic profiles have been constructed to characterize the distribution patterns of shrub-forest and herbaceous vegetation within the landscape. Based on calculations of phytosociological indicators for the main ecological factors, graphical patterns of their variation were developed. It was determined that the characteristic forests of the district, Tilieto-Carpinetum (Carpinion betulis), are represented by four variants (T.-C. var. galeobdolosum; T.-C. var. hepaticosum; T.-C. var. caricosum pilosae; T.-C. var. isopyrosum). The district is also characterized by the presence of syntaxa associated with carbonate soils, both of the marsh type (Caricion davallianae) and the meadow-steppe type (Cirsio-Brachypodion, Festucion valesiacae), with the dominance of Carex humilis and Stipa capillata. Using DCA-analysis, the correlation between ecological factor indicators and the distribution of plant communities within the ecological space has been established, forming six fields distributed along three vectors: by moisture (aquatic and marsh communities), xerophytism, and chemical properties of soils (meadow-steppe communities), as well as the structure of coenoses with a specific ombroregime (forest communities).

Testing of UV fluorescence marking with daily recaptures of a low-mobile bush-cricket species

The primary goal of developing new mark–release–recapture (MRR) methods is to make MMR more cost-effective and able to provide more information. To test the effectiveness of UV fluorescence marking, a case study was carried out on an Isophya costata population occurring in a mown grassland with a heterogeneous vegetation pattern. The marked individuals were examined daily, from the emergence of imagos until the mowing of the habitat. The 40 marked insects (20 males and 20 females) were recaptured in 206 cases over 16 days (32.2% of the potential maximal recaptures). The finding of males was 26.2% successful, and the finding of females was 38.1% successful. Females released in shorter and sparse vegetation were recaptured more than those released in dense vegetation or than males. Recaptures showed a significant decrease during the study period in almost all groups based on Mann–Kendall trend tests. Detections were made on the upper third of the vertical structure of the vegetation in 88% of cases. In most of the detections (males: 70%, females: 62%), the axis of the insect’s body was more likely to be located vertically. The results showed that the chance of detection is significantly reduced when the position of the insect’s body is facing the axis of UV illumination. Thus, the visibility of individuals can be greatly increased by marking all sides of the body.

Distribution Patterns of Urban Spontaneous Vegetation Diversity and Their Response to Habitat Heterogeneity: A Case Study of Five Cities in Heilongjiang Province, China.

Spontaneous vegetation is an important component of urban biodiversity and an excellent agent for exploring the mutual feedback mechanism between urbanization and urban ecosystems. Rapid urbanization has had a significant impact on the composition, structure, and distribution patterns of urban spontaneous vegetation diversity. Studying the diversity distribution patterns and causes of urban plant communities is beneficial for understanding the formation and maintenance mechanisms of plant diversity in specific urban habitats. This study selected five cities in different climate subregions of Heilongjiang Province as research targets and conducted field research using uniform sampling and typical sampling methods. The composition, distribution pattern, and driving factors of spontaneous vegetation were analyzed. The results showed the following: (1) A total of 633 examples of spontaneous vegetation were recorded, belonging to 93 families and 341 genera, mainly consisting of herbaceous plants and native plants. (2) The diversity index and similarity index of spontaneous vegetation in gravel-type abandoned land habitats are higher than those in other habitat types, while the diversity index of spontaneous vegetation in trees and shrubs is lower, and there is no significant difference in regards to different habitats. (3) Urban population density is a key factor affecting the diversity of native plants, while woody plant coverage, patch area, and landscape trait index are key factors affecting non-native plants. (4) The results of canonical correspondence analysis (CCA) showed that the total explanatory power of environmental characteristic factors in regards to the distribution pattern of spontaneous vegetation was 7.5%. The closest distance between adjacent patches, the coverage of woody plants in patches, the distance from the city edge, the patch area, and the surface impermeability of the buffer zones were key factors affecting the distribution of dominant species in spontaneous vegetation communities. The research results will provide an important reference for the conservation of urban biodiversity and the construction of low-maintenance urban green space plant landscapes in Heilongjiang Province.

Diversified Vegetation Cover Alleviates Microbial Resource Limitations within Soil Aggregates in Tailings.

Resource demand by soil microorganisms critically influences microbial metabolism and then influences ecosystem resilience and multifunctionality. The ecological remediation of abandoned tailings is a topic of broad interest, yet our understanding of microbial metabolic status in restored soils, particularly at the aggregate scale, remains limited. This study investigated microbial resources within soil aggregates from revegetated tailings and applied a vector model of ecoenzymatic stoichiometry to examine how different vegetation patterns (grassland, forest, or bare land control) impact microbial resource limitation. Five-year vegetation restoration significantly elevated carbon (C) and nitrogen (N) concentrations and their stoichiometric ratios in soil aggregates (approximately 2-fold), although these increases were not translated to in the microbial biomass and its stoichiometry. The activities of C- and phosphorus (P)-acquiring extracellular enzymes in these aggregates increased substantially postvegetation, with the most pronounced escalation in macroaggregates (>0.25 mm). The vector model results indicated soil microbial metabolism was colimited by C and P, most acutely in microaggregates (<0.25 mm). This colimitation was exacerbated by monotypic vegetation cover but mitigated under diversified vegetation cover. Soil nutrient stoichiometric ratios in vegetation restoration controlled microbial resource limitation, overshadowing the impact of heavy metals. Our findings underscore that optimizing resource allocation within soil aggregates through strategic revegetation can enhance microbial metabolism in tailings, which advocates for the implementation of diverse vegetation covers as a viable strategy to improve the ecological development of degraded landscapes.

Hidden Archaeological Remains in Heterogeneous Vegetation: A Crop Marks Study in Fortified Settlements of Northwestern Iberian Peninsula

This study evaluates the effectiveness of multispectral imaging via Unmanned Aerial Systems (UAS), in combination with advanced digital image processing techniques, for the detection and mapping of archaeological sites within diverse landscapes. The research focuses on six case studies located in the northwest of the Iberian Peninsula, a region marked by complex vegetation patterns and varying topography. The primary objective is to assess the potential of these non-invasive remote sensing techniques in identifying crop marks associated with buried structures from ancient, fortified settlements. By means of Principal Component Analysis (PCA) and vegetation indices, the study aims to pinpoint areas of interest that may indicate the presence of archaeological features, while effectively distinguishing them from modern disturbances or natural terrain variations. The research encountered several challenges, including seasonal variations in crop conditions and recent land-use changes. The methodology successfully identified distinct archaeological features. In some instances, natural vegetation variability, typically seen as an obstacle, enhanced the visibility of crop marks, aiding in the detection of underlying structures. These results offer a cost-effective and scalable option for preliminary archaeological surveys, particularly in refining survey methodologies and guiding future excavation efforts aimed at uncovering and preserving ancient, fortified settlements in the region.