Plant Research Articles

The Conservation Challenge: Environmental and Legal Aspects of One-Horned Rhino (Rhinoceros unicornis) Protection in India

The natural environment, with its lush landscapes and diverse ecosystems, serves as a vital refuge for a wide array of majestic animals and vibrant plant life, playing a crucial role in maintaining the delicate balance of our planet's ecological systems. One particularly remarkable species, the Greater One-Horned Rhino, faces the serious and pressing threat of being classified as vulnerable by the International Union for Conservation of Nature (IUCN) due to rampant poaching and the relentless loss of its natural habitat. In the Indian subcontinent, home to a significant population of these incredible creatures, the rhino's existence is under severe jeopardy, leading to distressing conflicts between human communities and the rhinos as the animals venture beyond protected areas in search of sustenance. Despite the presence of both national and international regulations, the peril to their existence persists, casting a shadow over their future. It is imperative that we take swift and effective measures to safeguard this magnificent species. This paper is dedicated to thoroughly examining the status of the Greater One-Horned Rhinos and to proposing practical and viable solutions aimed at ensuring their protection and survival for generations to come.

A Novel Web-Based Approach for Monitoring Biodiversity.

Understanding complexities in biodiversity is one of the fundamental goals of ecology and its monitoring is significant for ecosystem sustainability, maintenance, and conservation. However, biodiversity monitoring needs improvement to handle complex datasets and their analyses. This study attempts to understand these ecological complexities quickly, efficiently, and easily. The aim is to provide an alternative to ecologists, researchers, instructors, and stakeholders for biodiversity monitoring with the flexibility to visualize and customize outputs without software knowledge. A novel web-based technique is applied to monitor the biodiversity of a complex mountain ecosystem using a national database. The species-environment relationships of different vegetation types across a mountain ecosystem's elevation gradient are investigated using open-source climatic, physiographic, and socioeconomic variables. The proposed interactive tool to monitor biodiversity and understand its complexities is designed to visualize the data structure, summary, correlations, and sampling effectiveness quickly and easily. Plant species richness patterns and life forms (herb, shrub, and tree) across elevational gradients are investigated. We highlight the preliminary investigation of the data structure and their spatial distribution and apply the multicollinearity test to select variables for modeling. The drop-down menu helps users browse different datasets and select those datasets for instant visualization. Preliminary investigations on interactions between variables and species richness of vegetation types along elevation gradient interactively displayed with options to select variables, plant richness, and an elevational range. Species-environment relationships are investigated using multiple modeling protocols, and results are interactively displayed with options to download in different file formats and colors at the click of a button. This visualization tool helps to understand ecosystem structure, species richness patterns and species-environment relationships easily and efficiently. The R-codes used in this tool are reproducible and can be implemented with multiple datasets to monitor ecosystems.

Morpho-molecular characterization of fungi associated with seeds of hybrid rice varieties in bangladesh

Rice, as the dominant crop in Bangladesh, is vulnerable to various fungal pathogens. Many of these pathogens infect the seeds, which can later transmit diseases and serve as an efficient means for spreading seed-borne pathogens over long distances. In this study, seven hybrid rice varieties, specifically BRRI Hybrid Dhan 101 through BRRI Hybrid Dhan 107, were collected from the Bangladesh Rice Research Institute (BRRI) to detect and identify seed-borne fungi using both morphological and molecular techniques. Fourteen fungal species were isolated from the selected rice varieties using “Tissue planting method” and “Blotter method”, of which 4 fungal isolates were identified by molecular techniques. Molecular characterization of the isolates was conducted based on the sequence information of internal transcribed spacer (ITS) regions. The sequences obtained using the ITS1 and ITS4 primers were compared with those in the NCBI GenBank using BLAST analysis. Hybrid rice is comparatively more advantageous than inbreed rice because of its high yield, shorter plant life, and higher assimilation translocation. Therefore, it is crucial to identify and manage the pathogenic fungi associated with the seeds to ensure good seed quality, which can contribute to improving the economy of Bangladesh. Bangladesh J. Bot. 53(3): 511-518, 2024 (September)

Phytogeographical and biological spectrum of vascular flora as an indicator of ecological changes following clear-cutting in Eastern Serbian beech forest sites

Extreme weather events caused considerable harm to the forest ecosystems in Eastern Serbia over a few hard winters, resulting in widespread ice breaks and ice uprooting. Certain forest stands were severely impacted during the winter of 2014-2015, necessitating clear-cutting measures. This research was conducted in the Timok forest area, through examination of the floristic composition in areas subjected to clear-cutting, including natural beech forests and artificially established conifer stands within beech sites (Helleboro odori-Fagetum moesiacae). A phytogeographical and bioecological analysis was conducted five years after clear-cutting. Changes in ecosystems were assessed by analysing the spectra of area-types and plant life forms, with comparisons drawn to the “Vinatovača” old-growth forest, situated in the submontane beech forest of Eastern Serbia. Descriptive analysis of the phytogeographical and bioecological spectra of vascular flora, alongside multinomial correspondence analysis, revealed an increased presence of species from Eurasian, Mediterranean-sub-Mediterranean, and Pontic area-types, as well as hemicryptophytic, phanerophytic, and therophytic life forms in the clear-cut areas. In contrast, the old-growth forest was colonised by species of Central European and Holarctic area-types, along with geophytic life forms. These findings suggest a shift towards xerothermic microclimates in the clear-cut areas and the stronger influence of the continental climate of Eastern Serbia with its extremes on deforested areas, as well as on the processes of forest ecosystem degradation.

Archaeology of Ruderal Futurism

Language used to describe plant life and their environments is shaped by how plants are perceived. In turn this language reproduces how plants continue to be perceived and contributes to the further shaping of attitudes toward them. This essay presents the ruderal as a framework for understanding and envisioning being-with more-than-human others in a world altered by colonial and capitalist exploitation, extraction and expansion. Enacting an archaeological tracing of language and cultural thought towards ruderal plant species, consideration is given to: vernacular language applied to vegetal beings; identities of belonging applied to the movement of vegetation at a planetary scale; and decolonial modes of thinking-with and being-with vegetal others in the aftermath of colonialism and capitalism. Particular consideration here is given to the classification systems of botanist Albert Thellung, the thought of gardener and landscape architect Gilles Clément and the work of artist Andrea Callar. This paper extends an ongoing area of research I have previously examined in the curatorial research project Ruderal Futures (2022) for SixtyEight Art Institute and the essay ‘A brief constellation towards a ruderal futurism’ (2020).

Expansion and diversification of the Glycine max (Gm) ERD15-like subfamily of the PAM2-like superfamily.

Despite modulating senescence and drought responses, the GmERD15-like subfamily members are differentially induced by multiple stresses and diverge partially in stress signaling functions. The PAM2 motif represents a binding site for poly (A)-binding proteins (PABPs), often associated with RNA metabolism regulation. The PAM2-containing protein ERD15 stands out as a critical regulator of diverse stress responses in plants. Despite the relevance of the PAM2 motif, a comprehensive analysis of the PAM2 superfamily and ERD15-like subfamily in the plant kingdom is lacking. Here, we provide an extensive in silico analysis of the PAM2 superfamily and the ERD15-like subfamily in soybean, using Arabidopsis and rice sequences as prototypes. The Glycine max ERD15-like subfamily members were clustered in pairs, likely originating from DNA-based gene duplication, as the paralogs display high sequence conservation, similar exon/intron genome organization, and are undergoing purifying selection. Complementation analyses of an aterd15 mutant demonstrated that the plant ERD15-like subfamily members are functionally redundant in response to drought, osmotic stress, and dark-induced senescence. Nevertheless, the soybean members displayed differential expression profiles, biochemical activity, and subcellular localization, consistent with functional diversification. The expression profiles of Glyma04G138600 under salicylic acid (SA) and abscisic acid (ABA) treatments differed oppositely from those of the other GmERD15-like genes. Abiotic stress-induced coexpression analysis with soybean PABPs showed that Glyma04G138600 was clustered separately from other GmERD15s. In contrast to the AtERD15 stress-induced nuclear redistribution, Glyma04G138600 and Glyma02G260800 localized to the cytoplasm, while Glyma03G131900 fractionated between the cytoplasm and nucleus under normal and stress conditions. These data collectively indicate that despite modulating senescence and drought responses, the GmERD15-like subfamily members are differentially induced by multiple stresses and may diverge partially in stress signaling functions.

Betulonic Acid Inhibits Type-2 Porcine Reproductive and Respiratory Syndrome Virus Replication by Downregulating Cellular ATP Production.

Porcine reproductive and respiratory syndrome (PRRS), caused by PRRS virus (PRRSV) infection, has been a serious threat to the pork industry worldwide and continues to bring significant economic loss. Current vaccination strategies offer limited protection against PRRSV transmission, highlighting the urgent need for novel antiviral approaches. In the present study, we reported for the first time that betulonic acid (BA), a widely available pentacyclic triterpenoids throughout the plant kingdom, exhibited potent inhibition on PRRSV infections in both Marc-145 cells and primary porcine alveolar macrophages (PAMs), with IC50 values ranging from 3.3 µM to 3.7 µM against three different type-2 PRRSV strains. Mechanistically, we showed that PRRSV replication relies on energy supply from cellular ATP production, and BA inhibits PRRSV infection by reducing cellular ATP production. Our findings indicate that controlling host ATP production could be a potential strategy to combat PRRSV infections, and that BA might be a promising therapeutic agent against PRRSV epidemics.

JPaleoDB: One-Stop Search for Japan's Paleontological Collections

The Japan Paleobiology Database (jPaleoDB)*1*2 is a portal website for one-stop searching of paleontological specimens housed in museums across Japan. It contains data for over 430,000 specimen records from 50 museums and institutions as of July 2024 (Table 1). These records include over 7,000 holotypes, more than 100,000 voucher specimens, and represent over 13,000 genera in the Animalia kingdom, over 1,100 genera in the Plantae kingdom, and over 980 genera from other groups. This portal site allows users to search for paleontological specimens from various museums simultaneously, eliminating the need to navigate individual museum databases with different formats and search systems. Search results provide users with detailed information about each specimen, including scientific name, locality, repository, catalog number, type status, and publication. Additionally, results link directly to the corresponding specimen page on each museum's website. jPaleoDB's mission is to establish a network that facilitates the use of paleontological specimens in Japan for research and education. It has further expanded to support curatorial work in each museum by digitizing catalogs to create datasets of currently hidden paleontological collections. jPaleoDB is a research project built and operated by a group of individual researchers from universities and museums, not by a large organization like a national agency or academic society. Integrating data from museums that house specimens is challenging due to the difficulty of automation. As a result, much of the data requires manual curation. In addition, data for voucher specimens described in publications (paleontological papers, illustrated books, catalogs) are incorporated into jPaleoDB by analyzing publicly available resources and examining actual specimens at museums. Because of these reasons, jPaleoDB is still under development. We believe this portal site will be valuable for exploring the comprehensive record of paleontological specimens in Japan and helping users locate specific specimens of interest.

Synthesis and pharmacological evaluation of nature-inspired phenacyl glycosides

Phenylethanoid glycosides are a well-studied class of bioactive compounds found throughout the plant kingdom. In contrast, research on the synthesis and pharmacological activity of phenacyl glycosides, a specific subgroup of phenylethanoid glycosides with a ketone functionality at the alpha position of the phenol ring, has been limited. In this study, we report the synthesis, cytotoxic, antiviral, and anti-inflammatory evaluation of a series of 18 4′-hydroxyphenacyl glycosides. These compounds consist of six different sugar residues (β-d-glucose, β-d-galactose, α-l-arabinose, β-d-xylose, α-l-rhamnose, and β-d-glucuronic acid) and display three distinct methoxylation patterns at the phenacyl ring, similar to the substitution motifs of anthocyanins. We obtained the target phenacyl glycosides in high yield and stereoselectivity through the coupling of benzoyl-protected trichloroacetimidate glycosyl donors and corresponding acetophenones. Our work represents the first total synthesis of the natural products 4′-hydroxyphenacyl-β-d-glucopyranoside (1) and 4′-hydroxy-3′-methoxyphenacyl-β-d-glucopyranoside (2). None of the phenacyl glycosides showed cytotoxicity against the tested cell lines. Notably, several of the synthesized compounds exhibited antiviral activity, with natural product 2 being the most active against herpes simplex virus type 1, while phenacyl arabinoside 9 and natural product 2 were the most active against human coronavirus OC43. Natural product 2 significantly inhibited the production of interleukin-6 in lipopolysaccharide-stimulated microglia cells. Overall, our findings highlight the importance of the sugar residue and phenacyl ring substitution pattern in modulating the antiviral activity of phenacyl glycosides. Natural product 2 and phenacyl arabinoside 9 emerge as promising leads for the development of antiviral agents.

Light Pollution: To What Extent We are Concerned About

Light pollution is now a global problem with a catastrophic impact on human health, environment, ecology, plant life cycle, and animals. Some nations have enacted laws aimed at limiting light pollution. Unfortunately, there is no such regulation in Bangladesh, and if there is, it is not being enforced. In this study, an attempt has been made to investigate people's perceptions of light pollution in Bangladesh. This study collected three hundred forty samples using a convenient sampling technique. Descriptive statistics were employed to analyze the data. Among the sources, the respondents identified commercial light, fireworks, light from the market, and light from billboards as the major sources of light pollution. Besides light from the neighbor's house, own domestic light, events light, and light from home were assumed to be the significant disturbing light sources. Findings showed that most respondents agreed with the hazardous impact of light pollution on human health, animals, the environment, and the ecosystem. Among the possible solutions, respondents recommended developing awareness, limiting light at night-time, cutting off unnecessary lights, and reducing the frequent use of decorative lights. Results conclude that people have a sound understanding and good perception of light pollution. So the associate agents can take appropriate steps toward light pollution control.

Growing at the arid edge: Anatomical variations in leaves are more extensive than in stems of five Mediterranean species across contrasting moisture regimes.

Increasing aridity in the Mediterranean region affects ecosystems and plant life. Various anatomical changes in plants help them cope with dry conditions. This study focused on anatomical differences in leaves and xylem of five co-occurring Mediterranean plant species namely Quercus calliprinos, Pistacia palaestina, Pistacia lentiscus, Rhamnus lycioides, and Phillyrea latifolia in wet and dry sites. Stomatal density, stomatal length, leaf mass area, lamina composition, percentage of intercellular air spaces, and mesophyll cell area in leaves of plants in wet and dry sites were analyzed. Xylem anatomy was assessed through vessel length and area in branches. In the dry site, three species had increased stomatal density and decreased stomatal length. Four species had increased palisade mesophyll and reduced air space volume. In contrast, phenotypic changes in the xylem were less pronounced; vessel length was unaffected by site conditions, but vessel diameter decreased in two species. Intercellular air spaces proved to be the most dynamic anatomical feature. Quercus calliprinos had the most extensive anatomical changes; Rhamnus lycioides had only minor changes. All these changes were observed in comparison to the species in the wet site. This study elucidated variations in anatomical responses in leaves among co-occurring Mediterranean plant species and identified the most dynamic traits. Understanding these adaptations provides valuable insights into the ability of plants to thrive under changing climate conditions.

Genome-wide identification of the OVATE family proteins and functional analysis of BhiOFP1, BhiOFP5, and BhiOFP18 during fruit development in wax gourd (Benincasa hispida)

OVATE family proteins (OFPs) are transcriptional regulators in plants. They have a common domain called the OVATE domain and control the development of leaves, fruits, and flowers in plants. Although the OFP gene family has been widely explored in the plant kingdom, the identification and characterization of this family have not yet been performed in wax gourd. In this study, we conducted a genome-wide investigation of the OFP gene family and identified 18 OFP (BhiOFP) genes in wax gourd. Next, we discovered their evolutionary relationships, conserved motifs, gene structures, cis-acting elements, and expression patterns. The BhiOFP genes were irregularly distributed on nine chromosomes, with only two BhiOFP genes containing introns. The BhiOFP gene promoters contained cis-acting elements in response to phytohormones and environmental signals. The majority of BhiOFP genes were derived from whole-genome duplication events. Expression analysis demonstrated that the BhiOFP genes showed disparate modes of expression and some of them were highly expressed in fruits. Overexpression of BhiOFP1, BhiOFP5, and BhiOFP18 in Arabidopsis resulted in dwarf plants, small rosette leaves, and shortened siliques, while the BhiOFP1 overexpression plants displayed a more severe phenotype. In summary, our study systematically analyzed the wax gourd OFP gene family, facilitated the functional research of BhiOFP1, BhiOFP5, and BhiOFP18, and offered a theoretical foundation for the improvement of wax gourd varieties with appropriate fruit length.

Pervasive impacts of railway edge effects on edaphic parameters and vegetation distribution patterns

Addressing the ecological impacts of transport corridors while planning any transport network is paramount for a better of understanding ecological processes, biodiversity distribution, and ecosystem resilience. Here, we evaluated the impacts of railway edges on edaphic parameters, plant diversity, and composition in the northwestern Himalaya as a function of perpendicular distance from the railway track. In 2014 and 2017, we sampled vegetation plots across 31 sites distributed along 119 km of the Kashmir railway to test the effect of railway tracks on edaphic and vegetative parameters in short-term periods. T-shaped plots were laid comprising four sub-plots, one parallel to the track and the other three perpendiculars to it. We adopted the Mountain Invasion Research Network road survey methodology for data collection. We found (i) an increasing trend in all soil parameters (electrical conductivity, salinity, organic carbon, available nitrogen, and available phosphorus), except pH, as the distance from the railway track increased; (ii) significant railway edge effects on the importance value index of plant growth forms, life span, nativity and taxonomic group across space (distance of plots from the track) and time (2014–2017); and (iii) a significant spatiotemporal railway edge effects on plant species composition. Our results are pioneering in showing that railway tracks crossing through different ecosystems alter the edaphic conditions, resulting in direct and indirect edge effects on key abiotic and biotic factors, which in turn impact the vegetation of the surrounding natural habitats on both sides of the railway track. Our study contributes toward a better understanding of the role of anthropogenic edges like railways on edaphic parameters and vegetation distribution.

Research on the Application of Information Visualization Design Based on the Three-level Theory of Emotions

As society progresses, environmental challenges have emerged as a central concern in modern discourse. The degradation of ecosystems has led to the endangerment and extinction of numerous plant species. Moreover, the overwhelming influx of information available to individuals often hampers their understanding of the significance of these endangered species. Conventional written narratives are frequently inadequate in fulfilling the audience’s informational needs. As a nascent medium for scientific communication, information visualization presents an innovative and effective approach for individuals to swiftly acquire and interpret data. This paper concentrates on the endangered aquatic flora within the South China Botanical Garden, grounded in a three-tiered emotional theory framework. Strategies are developed across instinctual, behavioral, and reflective dimensions. The outlined strategic goals aim to elevate design aesthetic literacy, broaden cognitive processing capability, and enhance the efficiency of information dissemination. By employing endangered aquatic plants as a focal point for design initiatives in the South China Botanical Garden and integrating it with the theoretical framework, the objective is to present information regarding these vulnerable species in a more direct, inventive, and concise manner. This methodology aspires to raise public awareness surrounding the conservation of endangered plant life.

Arbuscular mycorrhizal fungal spore communities and co-occurrence networks demonstrate host-specific variation throughout the growing season

Microbial community assembly involves a series of ecological filtering mechanisms that determine the composition of microbial communities. While the importance of both broad and local level factors on microbial communities has been reasonably well studied, this work often is limited to single observations and neglects to consider how communities change over time (i.e., seasonal variation). Because seasonal variation is an important determinant of community assembly and determines the relative importance of community assembly filters, this represents a key knowledge gap. Due to their close associations with seasonal variation in plant growth and fitness, arbuscular mycorrhizal (AM) fungi are useful groups for assessing the importance of seasonal dynamics in microbial community assembly. We tested how seasonal variation (spring vs. summer), plant life history stage (vegetative vs. flowering), and host plant species (Baptisia bracteata var. leucophaea & Andropogon gerardii) influenced AM fungal spore community assembly. AM fungal spore community temporal dynamics were closely linked to plant host species and life history stage. While AM fungal spore communities demonstrated strong turnover between the spring (e.g., higher sporulation) and late summer (e.g., higher diversity), the strength and direction of these changes was modified by host plant species. Here we demonstrate the importance of considering temporal variation in microbial community assembly, and also show how plant-microbe interactions can modify seasonal trends in microbial community dynamics.

High and variable hydraulic resistance to embolism among three Asian juniper species

Over a background of a warming planet, with increasing occurrence of extreme climate events, junipers stand out as tree species thriving in inhospitable environments, enduring the cold, hot, and dry. Being part of the drought-adapted Cupressaceae Gray, some juniper species have been identified having among the most negative P50 values (vulnerability to xylem embolism) in the plant kingdom. Still, previous analyses skipped many Asian juniper species, some of which growing in arid conditions. Here we measured xylem vulnerability to embolism in three, yet unexplored, Asian juniper species: Juniperus drupacea growing in Israel, and J. pseudosabina and J. seravschanica growing in Uzbekistan. Branches were sampled from five trees per species and vulnerability curves were constructed using the Cavitron method, from which P50 was calculated. Xylem anatomy measurements were used to define torus overlap and maximum xylem specific hydraulic conductivity. These hydraulic traits were tested against species and site climate and in the context of species phylogeny. P50 of the Eastern Mediterranean J. drupacea was -11.8±0.3 MPa, much more negative than that of the two Asian junipers measured here, but within the same range of values measured in European and North American junipers. P50 was more negative with mean annual temperature and with aridity index of the driest quarter at both species (climatic conditions at the entire distribution range) and site levels. We did not find the relationships generally found in conifers between the properties of xylem pit membrane and vulnerability to embolism, nor with the overall aridity of the environment. To the best of our knowledge, our observations identify J. drupacea as the most drought-tolerant tree species in Asia.

Functional characterization of a small gene family coding for putrescine hydroxycinnamoyltransferases, involved in phenolamide accumulation, in tomato

Phenolamides are specialized metabolites widely distributed in the plant kingdom. Their structure is composed by the association of hydroxycinnamic acid derivatives to mono-/poly-amine through an amination catalyzed by N-hydroxycinnamoyltransferases enzymes. Tomato plants accumulate putrescine-derived phenolamides in their vegetative parts. Recently, two first genes coding for putrescine-hydroxycinnamoyltransferase (PHT, Solyc11g071470 and Solyc11g071480) were identified in tomato and demonstrated to control the leaf accumulation of caffeoylputrescine in response to leafminer infestation. In this study, two additional genes (Solyc06g074710 and Solyc11g066640) were functionally characterized as new tomato PHT. The substrate specificity and the expression pattern in planta were determined for the four tomato PHT. Taken together the results give a comprehensive view of the control of the putrescine-derived phenolamide accumulation in tomato plant through the biochemical specificity and the spatial expression of this small family of PHT.

Salish Perspectives on Human–Plant Relationships: Embracing Authenticity and Complexity

This paper explores the intricate relationship between humans and plants from the perspective of Salish concepts, shedding light on the tradition of attributing human-desired qualities to the botanical world. Although plants possess traits that appeal to human desires, it is essential to recognize their inherent distinction from humans. Through historical utilization by Salish communities, a spiritual reciprocal bond has been established, necessitating the adherence to human-like protocols to maintain a symbiotic relationship. However, this exploration advocates against romanticizing this relationship, as it has the potential to foster internal stereotyping while leading to external discrepancies in philosophical pursuits. By carefully examining Salish practices from past to present, an emphasis is placed on the significance of comprehending and respecting the uniqueness of plant life. Through this analysis, the primary goal is to enhance our understanding of the profound connection between humans and plants while embracing the authenticity and complexity of this relationship. Appreciating the true nature of the bond can offer valuable insights into sustainable coexistence with the botanical world and contribute to fostering a more balanced and respectful relationship between humans and the natural environment.

Spatio-temporal dynamics of net primary productivity and the economic value of Spartina alterniflora in the coastal regions of China

This study employs an improved Carnegie–Ames–Stanford Approach (CASA) model to calculate the Net Primary Productivity (NPP) of Spartina alterniflora (SA) and various other land use/land cover types (LULC) across coastal China over multiple years. The research aims to provide significant theoretical and practical insights into carbon sink research in coastal zones, sustainable development, and resource management. Key findings include identifying the first εmax value of 2.219 g C/MJ for SA, addressing a critical data gap in CASA modeling research on invasive plants. SA's NPP exhibited higher values in Shanghai and Zhejiang due to factors such as genetic diversity, invasion duration, and tidal dynamics. In contrast, other LULC exhibited higher NPP values in southern and inland regions, characterized by greater vegetation cover and favorable growing conditions. In 2020, SA and other LULC sequestered 16.352 kt C and 0.821*106 kt C, respectively. From 2000 to 2020, the average annual NPP and total carbon storage of SA and other LULC increased significantly, primarily driven by Shanghai and deciduous needleleaf forests, respectively. Seasonal NPP trends followed summer> spring> autumn> winter, influenced by climate conditions and plant life activities. Economic assessments in 2020 estimated SA's carbon storage value at RMB0.409 billion (Market Value method) or RMB5.562 billion (Carbon Tax method), with RMB2.054 billion attributed to oxygen release values, underscoring its economic and ecological potential. Among other LULC, evergreen broadleaf forests showed the highest carbon storage value (RMB183.463 billion). The study emphasizes the critical role of all LULC in carbon storage and oxygen release, advocating for targeted conservation and land management strategies. It suggests that managing SA should balance stringent control in high-risk areas, lenient measures in low-risk areas, eradication of scattered populations, and maximizing ecological benefits in retention areas, with continuous monitoring and adaptive management strategies to balance conservation and development efforts.

Variation patterns in foliar δ13C and δ15N among plant life types along an altitudinal gradient on the Tibetan Plateau

Understanding how foliar δ13C and δ15N vary with the environment is crucial for elucidating the carbon and nitrogen cycle dynamics within ecosystems. Yet, there is limited knowledge about these variations among different plant life types along altitudinal gradients, particularly in subtropical forest ecosystems found in the southeastern Tibetan Plateau. Therefore, we collected leaves from 67 species, including 20 trees, 24 shrubs, and 23 herbs along an altitudinal gradient of 834 m to 3105 m in the subtropical forest of Medog, and investigated their patterns of variation along the altitudinal gradient. Our findings revealed a positive relationship between foliar δ13C and altitude, as well as a negative relationship between foliar δ13C and soil temperature. There was no significant correlation between foliar δ15N and altitude, but a hump-shaped relationship was observed between foliar δ15N and soil moisture. Among the different plant functional groups, the δ13C of shrubs is more sensitive and representative of environmental changes. In addition, we discovered no difference in the δ13C (δ15N) values of leaves among trees, shrubs, and herbs in this study. Still, there were significant differences when compared to the δ13C (δ15N) values of leaves in other typical climatic zones, indicating that climatic zones influenced the δ13C and δ15N values of leaves more than plant functional groups. In conclusion, our results provide new insights into the climatic drivers of the changes in δ13C and δ15N of the different plant life types along the altitudinal gradient in the southeastern Tibetan Plateau.