Biome Research Articles

Establishment of Agrobacterium-Mediated Transient Transformation System in Desert Legume Eremosparton songoricum (Litv.) Vass.

Eremosparton songoricum (Litv.) Vass. is a desert legume exhibiting extreme drought tolerance and the ability to withstand various harsh environments, making it a good candidate for investigating stress tolerance mechanisms and exploring valuable stress-resistant genes. However, the absence of a genetic transformation system for E. songoricum poses significant limitations for functionally validating these stress-resistant genes in situ. In this study, we developed an Agrobacterium-mediated transient transformation system for E. songoricum utilizing the β-glucuronidase (GUS) gene as a reporter. We investigated three types of explants (seedlings, assimilated branches and callus) and the effects of different Agrobacterium strains, seedling ages, OD600 values, acetosyringone (AS) concentrations, sucrose concentrations and infection times on the transformation efficiency. The results reveal that the optimal transformation system was infecting one-month-old regenerating assimilated branches with the Agrobacterium strain C58C1. The infection solution comprised 1/2 MS medium with 3% sucrose and 200 μM AS at an OD600 of 0.8, infection for 3 h and then followed by 2 days of dark cultivation, which achieving a maximum transformation rate of 97%. The maximum transformation rates of the seedlings and calluses were 57.17% and 39.51%, respectively. Moreover, we successfully utilized the assimilated branch transient transformation system to confirm the role of the previously reported transcription factor EsDREB2B in E. songoricum. The overexpression of EsDREB2B enhanced drought tolerance by increasing the plant’s reactive oxygen species (ROS) scavenging capacity in situ. This study established the first transient transformation system for a desert legume woody plant, E. songoricum. This efficient system can be readily applied to investigate gene functions in E. songoricum. It will expedite the exploration of genetic resources and stress tolerance mechanisms in this species, offering valuable insights and serving as a reference for the transformation of other desert plants and woody legumes.

Transcriptional Profiling Analysis Providing Insights into the Harsh Environments Tolerance Mechanisms of Krascheninnikovia arborescens

Krascheninnikovia arborescens, an endemic shrub in China, thrives in desertification-prone environments due to its robust biomass, hairy leaves, and extensive root system. It is vital for ecological restoration and serves as a valuable forage plant. This study explored the molecular mechanisms underlying K. arborescens’ adaptation to desert conditions, focusing on its physiological, biochemical, and transcriptomic responses to drought, salt, and alkali stresses. The results revealed that the three stresses have significant impacts on the photosynthetic, antioxidant, and ion balance systems of the plants, with the alkali stress inducing the most pronounced changes and differential gene expression. The clustering and functional enrichment analyses of differentially expressed genes (DEGs) highlighted the enrichment of the induced genes in pathways related to plant hormone signaling, phenylpropanoid biosynthesis, and transcription factors following stress treatments. In these pathways, the synthesis and signal transduction of abscisic acid (ABA) and ethylene, as well as the flavonoid and lignin synthesis pathways, and transcription factors such as MYB, AP2/ERF, bHLH, NAC, and WRKY responded actively to the stress and played pivotal roles. Through the WGCNA analysis, 10 key modules were identified, with the yellow module demonstrating a high correlation with the ABA and anthocyanin contents, while the turquoise module was enriched in the majority of genes related to hormone and phenylpropanoid pathways. The analysis of hub genes in these modules highlighted the significant roles of the bHLH and MYB transcription factors. These findings could offer new insights into the molecular mechanisms that enable the adaptation of K. arborescens to desert environments, enhancing our understanding of how other desert plants adapt to harsh conditions. These insights are crucial for exploring and utilizing high-quality forage plant germplasm resources and ecological development, with the identified candidate genes serving as valuable targets for further research on stress-resistant genes.

Chromosome-scale genome assembly of Apocynum pictum, a drought-tolerant medicinal plant from the Tarim Basin.

Apocynum pictum Schrenk is a semishrub of the Apocynaceae family with a wide distribution throughout the Tarim Basin that holds significant ecological, medicinal, and economic values. Here, we report the assembly of its chromosome-level reference genome using Nanopore long-read, Illumina HiSeq paired-end, and high-throughput chromosome conformation capture sequencing. The final assembly is 225.32 Mb in length with a scaffold N50 of 19.64 Mb. It contains 23,147 protein-coding genes across 11 chromosomes, 21,148 of which (91.36%) have protein functional annotations. Comparative genomics analysis revealed that A. pictum diverged from the closely related species Apocynum venetum approximately 2.2 million years ago and has not undergone additional polyploidizations after the core eudicot WGT-γ event. Karyotype evolution analysis was used to characterize interchromosomal rearrangements in representative Apocynaceae species and revealed that several A. pictum chromosomes were derived entirely from single chromosomes of the ancestral eudicot karyotype. Finally, we identified 50 members of the well-known stress-responsive WRKY transcription factor family and used transcriptomic data to document changes in their expression at 2 stages of drought stress, identifying a number of promising candidate genes. Overall, this study provides high-quality genomic resources for evolutionary and comparative genomics of the Apocynaceae, as well as initial molecular insights into the drought adaptation of this valuable desert plant.

An improved instantaneous gross primary productivity model considering the difference in contributions of sunlit and shaded leaves to canopy sun-induced chlorophyll fluorescence

Sun-induced chlorophyll fluorescence (SIF) from plants offers an effective proxy for estimating gross primary productivity (GPP) by modeling SIF-GPP relationships, a widely used method to evaluate the global carbon sink. However, most SIF-GPP models ignore SIF differences between shaded and sunlit leaves, resulting in GPP underestimation, particularly in dense vegetation. This study aims to partition the contributions of sunlit and shaded leaves to canopy SIF and GPP to refine the SIF-GPP estimation model. Data from 40 eddy covariance (EC) sites representing eight major biomes and TROPOMI SIF satellite data were used for site-specific and global-scale analyses. Our results showed that the contributions of sunlit and shaded leaves to canopy SIF were 80 % and 20 %, and to canopy GPP were 55 % and 45 %, respectively. For site-specific or satellite data, the SIF-GPP relationships were the strongest for sunlit leaves (R2 > 0.51, RMSE = 4.03 μmol m−2 s−1, p < 0.001). The new SIF-GPP model, including sunlit-shaded SIF separation, can improve the accuracy of GPP estimation (R2 = 0.53, RMSE = 4.38 μmol m−2 s−1, p < 0.001). Compared with the model established with observed data, R2 was increased by 0.1, and RMSE decreased by 13.26 μmol m−2 s−1, indicating that the ‘two-leaf’ model could notably improve the SIF-GPP model. This study confirms the different contributions of sunlit and shaded leaves to canopy SIF and GPP, and ignoring this disparity would induce systematic bias in GPP estimation. Our methods and findings on sunlit-shaded SIF separation can be referenced by other studies to enhance GPP estimation accuracy.

Adaptive water use strategies of artificially revegetated plants in a water-limited desert: A case study from the Mu Us Sandy Land

Understanding the water use patterns of artificially revegetated plants in arid and semi-arid desert regions with shallow groundwater is crucial for sustainable water resource management and effective vegetation restoration strategies. Despite extensive vegetation rehabilitation in the Mu Us Sandy Land (MUSL), the interspecific and seasonal variations in plant water sources under similar groundwater conditions remain unclear. We conducted isotopic analysis of hydrogen and oxygen in main sand-fixing plants—Pinus sylvestris var. mongolica, Amygdalus pcdunculata Pall, and Artemisia desertorum Spreng—alongside potential water sources during the 2019–2021 growing seasons. Our aim was to elucidate seasonal changes in plant water uptake patterns by correcting isotopic offsets in xylem water using the MixSIAR model. Results indicated that A. desertorum predominantly utilized water from the 0–150 cm soil layer (67.52 ± 14.44 %) throughout all seasons. Conversely, P. sylvestris and A. pedunculata shifted their primary water sources from the 60–240 cm soil layer during the dry season (55.20 ± 2.12 and 57.96 ± 1.45 %, respectively) to the 0–150 cm soil layer during the rainy season (68.44 ± 4.46 and 66.19 ± 1.68 %, respectively), suggesting greater water uptake adaptability in trees and shrubs compared to grasses. Groundwater contribution to plant water uptake showed no significant interspecies difference during the rainy season (p > 0.05). However, P. sylvestris and A. pedunculata significantly increased groundwater absorption during the dry season compared to the rainy season (p < 0.05). Correcting δ2H offsets in xylem water revealed an underestimation of groundwater contributions by 16.06 ± 9.09 % in the dry season and 4.25 ± 0.55 % in the rainy season. Given these interspecific and seasonal variations in water uptake patterns among sand-fixing plants, and the imperative for sustainable groundwater use, tailored water management strategies are essential to prevent the degradation of restored ecosystems in this water-limited desert region.

An Artemisia Sphaerocephala Krash gum/acrylic acid-based novel eco-friendly superabsorbent polymer: Its synthesis and properties promoting seed germination

An affordable, eco-friendly, and salt-tolerant superabsorbent polymer (SAP) has been synthesised from Artemisia sphaerocephala Krasch gum (ASKG), a naturally hydrophilic heteropolysaccharide extracted from the seeds of Artemisia sphaerocephala and acrylic acid (AA) through free-radical polymerisation (ASKG/AA-SAP) using ammonium persulfate (APS) as the initiator and N, N´-methylenebisacrylamide (MBA) as the cross-linker. Morphological and thermal analyses confirmed that ASKG/AA-SAP showed a uniformly interconnected porous structure with a high thermal stability and a gradual decomposition rate. Notably, ASKG/AA-SAP demonstrated exceptional water absorbency, reaching maximum values of 1250g·g-1 in distilled water and 152g·g-1 in a 0.9wt% NaCl solution. Work on relevant parameters related to SAP, viz water absorbency, water retention, and reusability under different influencing factors has been carried out, as also the swelling capacity, salt tolerance, and the ability to withstand a wide range of pH values (4-12) and temperatures (5-55°C). Furthermore, ASKG/AA-SAP has also demonstrated water retention, viz maintaining a rate of 34.19% after 5h in distilled water, which are superior to those of other SAPS tested. Interestingly, the application of ASKG/AA-SAP has resulted in a substantial improvement in seed germination of desert plant, as evidenced by an increase in germination rate and germination energy of Hedysarum scoparium by 58.66% and 35.71%, respectively, compared to the control group. ASKG/AA-SAP, therefore, holds excellent potential for application in agri-forestry production and afforestation works within arid and semi-arid regions.

Estimation of Forest Growing Stock Volume with Synthetic Aperture Radar: A Comparison of Model-Fitting Methods

Satellite-based estimation of forest variables including forest biomass relies on model-based approaches since forest biomass cannot be directly measured from space. Such models require ground reference data to adapt to the local forest structure and acquired satellite data. For wide-area mapping, such reference data are too sparse to train the biomass retrieval model and approaches for calibrating that are independent from training data are sought. In this study, we compare the performance of one such calibration approach with the traditional regression modelling using reference measurements. The performance was evaluated at four sites representative of the major forest biomes in Europe focusing on growing stock volume (GSV) prediction from time series of C-band Sentinel-1 and Advanced Land Observing Satellite Phased Array L-band Synthetic Aperture Radar (ALOS-2 PALSAR-2) backscatter measurements. The retrieval model was based on a Water Cloud Model (WCM) and integrated two forest structural functions. The WCM trained with plot inventory GSV values or calibrated with the aid of auxiliary data products correctly reproduced the trend between SAR backscatter and GSV measurements across all sites. The WCM-predicted backscatter was within the range of measurements for a given GSV level with average model residuals being smaller than the range of the observations. The accuracy of the GSV estimated with the calibrated WCM was close to the accuracy obtained with the trained WCM. The difference in terms of root mean square error (RMSE) was less than 5% units. This study demonstrates that it is possible to predict biomass without providing reference measurements for model training provided that the modelling scheme is physically based and the calibration is well set and understood.

Responses of Soil Water Potential and Plant Physiological Status to Pulsed Rainfall Events in Arid Northwestern China: Implications for Disclosing the Water‐Use Strategies of Desert Plants

ABSTRACTSoil water potential (SWP) strongly influences plant productivity and ecosystem functioning, particularly in arid regions characterized by sporadic and pulsed rainfall. This work aims to improve understanding of the response of SWP to varied rainfall pulses, and of the water‐use strategies of a widespread C4 shrub (Haloxylon ammodendron, HA) in arid northwestern China. Rainfall manipulation experiments and field measurements on HA were undertaken to explore the response features of SWP and plant physiological status to pulsed rainfall events of varied magnitudes and durations. The physiological state of HA was evaluated by quantifying critical metrics indicative of plant water‐use strategies, including leaf water potential, photosynthetic rate and transpiration rate. The response value of SWP increased with rainfall magnitude and was most affected by three vital factors (antecedent SWP, total rainfall and rainfall intensity). Low antecedent SWP amplifies SWP's sensitivity to subsequent events, accelerating its response to smaller rainfalls (&lt;5 mm) compared with larger ones (&gt;15 mm). Small rainfall can increase SWP by 0.5–2 MPa in the 20‐cm layer, sustaining plant physiological activities under high antecedent SWP conditions (&gt;−3.5 MPa), with a maximum average rise in photosynthetic rate of 9.20 ± 0.45 μmol CO2 m−2 s−1, enhancing HA's water use efficiency to 1.79 ± 0.22 μmol CO2 mmol−1 H2O. Therefore, small events play a vital role in maintaining SWP and promoting water use of desert plants. Given the nature of plants' utilization of small rainfall events, re‐examining ecologically valid SWP thresholds of HA and other similar desert plants is critical.

The Long-Term Dynamics of Shrew Communities: Is There a Downward Trend?

Compared to other small mammals, shrews are understudied due to their limited impact on agriculture, lower biomedical importance, and difficulty to study. Based on trapping data from 1975–2023, we investigated changes in Lithuanian shrews (Sorex araneus, Sorex minutus, Neomys fodiens, and Neomys milleri) over six decades. We analyzed the relative abundance of shrews and the proportion of their species within small mammal communities to assess temporal patterns and distribution in major habitat types. The first main finding was the confirmation of a decrease in S. araneus abundance in the 2020s compared to the 1990s and 2010s. The species proportion in 2020s was lower than in the 1970s–2000s; the decrease started in the 1980s and accelerated in the 2000s. Abundances and proportions of S. minutus and N. fodiens showed no significant trend. The abundance of N. fodiens was very low. The relative abundances and proportions of Sorex species were highest in commensal (human-related) and mixed (including forest, wetland, and meadow) habitats. Shrews were underrepresented in agricultural habitats, with the numbers of both S. araneus and S. minutus 4.1 times lower than expected. While the presence of S. minutus in commensal habitats could be explained by their diet specificity, the capture of N. fodiens and N. milleri in commensal habitats is a novel feature of their ecology.

Landscape and local factors drive pesticide distribution in perennial agroecosystems

Abstract Pesticides constitute a major threat to biodiversity, but our understanding of the complex interactions between local and landscape factors influencing their distribution in agroecosystems remains limited. We conducted a pioneering study where we screened spiders, rodents, plants and soils for multiple pesticide residues in perennial crops (orchards and vineyards) managed under organic (N = 8) and integrated pest management (N = 8) systems. We then quantified the proportional representation of major habitat types in surrounding landscapes. Additionally, we conducted interviews with farmers to gain precise insights into pesticide applications. We expected that landscape factors would be more important for mobile entities (i.e. spiders and rodents), while management type would be relatively more important for the sedentary entities (i.e. soils and plants). We detected various pesticides within studied crop types, including several forbidden in the European Union. We found that pesticide distribution in spiders was influenced by the proportion of semi‐natural habitats in the landscape, with pesticide concentration decreasing as the proportion of semi‐natural habitats increased. Additionally, we observed that the spectrum of pesticides in spiders increased with the dominance of web‐building spiders. In contrast, pesticide levels in rodents were not affected by either landscape composition or local management type. For plants, pesticide distribution was affected by the proportion of forests and shrublands and, to some extent, by local management practices. In the case of soil, pesticide distribution was primarily determined by local management. This study marks an effort in demonstrating that both local and landscape factors play crucial roles in shaping pesticide distribution within perennial crops. Importantly, the relative importance of these factors varied across the four matrices investigated. Synthesis and applications: To comprehend the factors that determine pesticide distribution in crops, it is crucial to monitor diverse ecosystem components rather than focusing on a few model species. This approach underscores the necessity for ecologically sensitive management at landscape scale. Such management should involve the preservation and enhancement of (semi)natural habitats around crops. These combined insights can form the foundation for conservation and management initiatives aimed at mitigating the impact of pesticides on biodiversity within crops.

Spectroscopic analysis of wild medicinal desert plants from wadi sanor (beni-suef), Egypt, and their antimicrobial and antioxidant activities

Desert plants possess untapped potential for medicinal applications due to their rich phytochemical profiles. However, they need to be more explored. Thus, this study integrates advanced analytical, biochemical, and molecular techniques to investigate the phytochemical composition and biological activities (antimicrobial and antioxidant) of four desert plants (Pergularia tomentosa, Zygophyllum coccineum, Pulicaria undulata, and Ochradenus baccatus), collected from Wadi Sannor, Beni-Suef Governorate, Egypt, in March 2021. The volatile chemicals in the 70 % ethanol extracts of the selected plants were also analyzed using GC-MS. The extract exhibited strong antioxidant properties, as demonstrated by its FRAP (Ferric reducing ability of plasma) values, anti-lipid peroxidation, superoxide anion scavenging activity, and DPPH scavenging activity. Additionally, plants extracts showed high antimicrobial activities against seven pathogens, including three Gram-negative bacteria (Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli) and four Gram-positive bacteria (Staphylococcus saprophyticus, Staphylococcus epidermidis, Enterococcus faecalis, Streptococcus salivarius). Lastly, molecular docking was conducted for cis-vaccenic acid, (E)-9-octadecenoic acid, the cyclohepta[b]furan-2-one scaffold, and URS-20(30)-en-3-ol against both the thymidylate kinase enzyme and the active sites of E. coli DNA gyrase. The results from the molecular docking studies showed a strong correlation with the biological data. Moreover, these compounds exhibited good, proposed absorption, distribution, metabolism, and excretion–toxicity (ADMET) profiles. Our study highlights the potential of P. tomentosa, Z. coccineum, P. undulata, and O. baccatus for future medical applications and the development of new pharmaceuticals derived from desert flora.

Silver nanoparticles synthesized using aerial part of Achillea fragrantissima and evaluation of their bioactivities

Achillea fragrantissima (A. fragrantissima), a desert plant, is used internally in Arabian traditional medicine to treat inflammatory, spasmodic gastrointestinal disorders, and hepatobiliary diseases. The study focuses on the environmentally friendly production of silver nanoparticles (AgNPs) from the water-based aerial parts of the A. fragrantissima plant and their ability to kill bacteria and cells. Ultraviolet-visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FTIR) were used to describe the AgNPs. They were then tested for their ability to fight cancer and bacteria. A change in colour from yellow to brown and a surface plasmon resonance peak at 440 nm, seen with UV-Vis spectroscopy, showed that AgNPs had formed. In a Gas Chromatography-Mass Spectrometry (GC-MS) test of the aerial parts of A. fragrantissima, twenty bioactive components were found. These included isolongifolol and 3E,10Z-Oxacyclotrideca-3,10-diene-2,7-dione, methylbuta-1,3-dienyl)-7-oxabicyclo [4.1.0] heptan-3-ol. The extract exhibited high phenolic and flavonoid content (77.52 ± 1.46 mg GAE/g dry weight and 59 ± 2.17 mg QE/g dry weight, respectively). According to the IC50 values of 17.2 ± 1.18 and 14 ± 2.43 µg/mL, the AgNPs had a lot of power to kill cancer cells from the MCF-7 and HepG2 lines. Some genes that cause cell death (caspase-3, 8, 9, and Bax) were turned on more in the treated cells compared to the control cells that had not been treated. These genes were Bcl-xL and Bcl-2. Additionally, substantial activity against both Gram-positive bacteria and Gram-negative bacteria was found by antibacterial screening. Overall, this study underscores A. fragrantissima’s diverse biological activity and its potential in drug discovery and nanomedicine, promoting the development of natural antibacterial and anticancer therapies.

Unlocking the wound healing potential of Anastatica hierochuntica L. (Kaff Maryam) Extract's nanosuspension: UPLC-MS/MS metabolic profiling, formulation development and statistical optimization

BackgroundAnastatica hierochuntica L. (Kaff Maryam) is a desert plant with documented therapeutic applications. Various medicinal uses have been reported for the plant extract such as antioxidant, anti-inflammatory, antifungal, antimicrobial, hypoglycemic, hypolipidemic, and hepatoprotective activities. The abundant plants constituents are promising and encourage the investigation of novel therapeutic uses. The principal objective of this study was to identify the bioactive constituents of A. hierochuntica (AH) by phytochemical profiling of its ethanolic extract, alongside an investigation of its wound healing efficacy after being formulated into nanosuspension for topical localized wound treatment. MethodA comprehensive metabolomics study of the ethanolic extract of A. hierochuntica aerial parts was assessed using UPLC MS/MS technique. Additionally, the preparation of AH nanosuspension was executed utilizing the antisolvent-precipitation method. A D-optimal experimental design was adopted to investigate the influence of variables such as: stabilizer ratio, antisolvent: solvent ratio, and stabilizer type on particle size (PS), polydispersity index (PDI), and zeta potential (ZP). The design also was employed in the optimization process. The selected optimal formula was further assessed for size characteristics, morphological identification by TEM, storage stability, FTIR, cytocompatibility with human skin fibroblast (HSF), and scratch assay on HSF to assess wound healing aptitude. ResultsChemical profiling of the aerial parts revealed an abundance of glucosinolates, flavonoids, flavolignans, and fatty acids. The optimized AH-nanosuspension showed small particle size (128.87 ± 26 nm), small PDI (0.136 ± 0.05), and high ZP absolute value (−37.53 ± 0.52 mV). Furthermore, TEM photography of the optimal nanosuspension formula exhibited circular non-aggregating nanosized particles. FTIR confirmed the successful formulation of the AH ethanolic extract into nanosuspension with no physicochemical interactions. Additionally, AH-nanosuspension demonstrated cytocompatibility with HSF with IC50 = 58.317 μg/mL. Moreover, both AH pure extract and AH-nanosuspension exhibited a remarkable cell migration rate and wound closure % which propounds an auspicious wound healing potential. ConclusionThe study accentuates the supremacy of the nanosized delivery approach of AH aerial parts ethanolic extract and warrants further in-vivo investigations to establish its clinical utility for wound management.

Locating the suitable large-scale solar farms in China's deserts with environmental considerations

Desert areas offer rich solar resources and low land use costs, ideal for large-scale new energy development. However, desert ecosystems are fragile, and large-scale photovoltaic (PV) power facilities pose ecological risks. Current assessments of PV plant sites in deserts lack consideration of wind-sand hazards and ecological impacts. In this study, we have developed a new large-scale photovoltaic (PV) site selection model that integrates the analytic hierarchy process with geographic information system technology, and applies it to the desert regions of China. The results show that the potential for large-scale PV power plants in China's deserts is significant, with 69.4 % of the region assessed as medium or higher. The most suitable area is 12.7 × 104 km2 (7.6 % of the overall study area), mainly centered in the Tibetan Plateau's Qaidam Basin Desert and the deserts of northern China, characterized by favorable solar resources, climate, and terrain. Across all regions, gravel deserts are recognized as more suitable for the construction of large-scale PV power projects than sandy deserts. Considering varying PV installation density scenarios with an installed capacity potential of 36.4–84.9 TW and system costs ranging from 10.0 to 33.5 trillion USD, the study estimates an annual solar power generation potential of 47–110 PWh which is 1.7–3.9 times the global electricity demand. Carbon emissions could be reduced by 26.8–62.6 gigatons annually, offsetting 73–170 % of global emissions. Covering just 4.8–11.5 % of China's desert area (8 × 104–19.4 × 104 km2) would meet the projected 2025 electricity needs of the country. This study lays the groundwork for spatial planning and benefit assessment of large-scale PV projects in desert regions, and reduces conflicts between PV plant construction and local ecosystem.

A Study of the Diversity Patterns of Desert Vegetation Communities in an Arid Zone of China.

The Gobi Desert ecosystem is currently experiencing the impacts of persistent climate warming and extreme weather. However, the relative influences of factors such as soil, climate, and spatial variables on the β-diversity of desert plants and their key components have not been systematically studied. In this research, the Dunhuang North Mountain and Mazong Mountain areas were selected as study areas, with a total of 79 plant community plots systematically established. The aim was to explore intercommunity β-diversity and its components and to analyze the interrelationships with climate factors, soil factors, and geographic distance. The results indicate that (1) there is a geographic decay pattern and significant differences among plant communities in the Dunhuang North Mountain and Mazong Mountain areas, with β-diversity primarily driven by replacement components. (2) Climate, soil, and geographic distance significantly influence β-diversity and its replacement components, with climate factors exerting the greatest influence and geographic distance the least. (3) Multiple regression analysis (MRM) reveals differential effects of climate factors, soil factors, and geographic distance on β-diversity and its replacement components, with climate and soil factors exerting a much greater influence than geographic distance. In summary, the β-diversity of plant communities and their replacement components in the Dunhuang North Mountain and Mazong Mountain areas result from the combined effects of habitat filtering and dispersal limitation, with habitat filtering having a greater impact, while environmental heterogeneity is an important factor influencing species differences in this region.

A global database of soil seed bank richness, density, and abundance.

A soil seed bank is the collective name for viable seeds that are stored naturally in the soil. At the species or population level, the ability to form a seed bank represents a strategy for (re)colonization following a disturbance or other change in the local environmental conditions. At the community level, seed banks are thought to buffer local diversity during periods of environmental change and are often studied in relation to the potential for passive habitat restoration. The role that seed banks play in plant population and community dynamics, as well as their importance in the agricultural sector, means that they have been widely studied in ecological research. This database is the result of a comprehensive literature search, including all seed bank studies from the Web of Science from which data could be extracted, as well as an additional search of the Russian language literature. The database contains information on the species richness, seed density, and/or seed abundance in 3096 records from at least 1929 locations across the world's seven continents, extracted from 1442 studies published between 1940 and 2020. Records are grouped into five broad habitat categories (aquatic, arable, forest, grassland-including shrubland-and wetland), including information relating to habitat degradation from, or restoration to other habitats (total 14 combinations). Sampling protocols were also extracted for each record, and the database was extensively checked for errors. The location of each record was then used to extract summary climate data and biome classification from external published databases. The database has several potential uses. The large geographical spread relative to many other global biodiversity datasets is relevant for investigating patterns of diversity in biogeographical or macroecological contexts. Habitat type and status (intact, degraded, and restored) can be used to provide insights for biodiversity conservation, while the potential effects of sampling method and effort can be used to inform optimized data collection for future seed bank studies. This database is released under the CC-BY license.

Aral Environmental Disaster and Its Mitigation Through Forest Plantations

Abstract The drained bottom of the Aral Sea poses a serious threat to all living things in the Aral Sea region because it covers an area of about 6 million hectares. Nearly150 million tons of salt, dust, and sand are released into the air from it annually, which causes significant damage to agriculture and the national economy. It is possible to mitigate the ecological catastrophe by creating forest plantations on the drained bottom from desert plants. Depending on the types of bottom sediments, different technologies for creating forest plantations were tested, which made it possible to obtain highly effective plantations and minimize the negative impact of the dried bottom of the Aral Sea. Globally, the ecological problem of the Aral Sea is regarded as one of the critical issues that require immediate attention, the consequences of which are still being felt on a continental scale.

The species diversity and phylogenetic structure patterns of desert plant communities in the Turpan-Hami region, Xinjiang

Desert plant communities play a crucial role in enhancing desert ecosystem productivity and stability but are highly susceptible to environmental changes owing to their limited resilience and resistance to disturbances, making it essential to understand the factors influencing their diversity patterns and community structure, particularly under the threat of climate change and intensifying droughts. This study focused on the Turpan-Hami desert region, a typical desert ecosystem in which diversity patterns and community structures remain unclear. We established 101 sampling sites ranging from elevations of -134 to 2056m and recorded community information, including species composition, height, coverage, and density, using the sample plot method. The diversity patterns were analyzed using regression analysis, and the phylogenetic structure was assessed. Additionally, Canonical Correspondence Analysis, Mantel tests, and General Linear Models were used to identify the key factors affecting community structure. Our results demonstrated that the species richness and phylogenetic diversity of plant communities exhibited a monotonic increase with elevation, and the phylogenetic structure exhibited low clustering and high dispersion along the elevational gradient. The annual mean temperature emerged as the most significant factor influencing diversity patterns, with soil nutrients, such as total potassium and available phosphorus, also affecting the spatial distribution of diversity. Notably, no significant correlations were found between community phylogenetic structure and abiotic factors, highlighting the complex interactions that drive diversity in the Turpan-Hami region. This study offers valuable insights into the mechanisms shaping desert plant community diversity and is essential for biodiversity conservation efforts in fragile desert ecosystems amid climate change.

Population structure and natural selection across a flower color polymorphism in the desert plant Encelia farinosa.

Clines-or the geographic sorting of phenotypes across continual space-provide an opportunity to understand the interaction of dispersal, selection, and history in structuring polymorphisms. In this study, we combine field-sampling, genetics, climatic analyses, and machine learning to understand a flower color polymorphism in the wide-ranging desert annual Encelia farinosa. We find evidence for replicated transitions in disk floret color from brown to yellow across spatial scales, with the most prominent cline stretching ~100 km from southwestern United States into México. Because population structure across the cline is minimal, selection is more likely than drift to have an important role in determining cline width. Given that the cline aligns with a climatic transition but there is no evidence for pollinator preference for flower color, we hypothesize that floret color likely varies as a function of climatic conditions.

Response of Species Diversity and Stability of Typical Steppe Plant Communities on the Mongolian Plateau to Different Grazing Patterns

ABSTRACTGrasslands represent a major biome on Earth and play a vital role in ecosystem functioning and dynamics. However, owing to the variations among grassland types, the impact of grazing on plant community diversity and stability remains unclear. This study is based on the typical steppe of the Mongolian Plateau. Field sampling and data analysis were combined to qualitatively and quantitatively investigate the structural characteristics, species diversity, and stability of plant communities under varying grazing intensities, that is, four‐season nomadic, two‐season rotational, and sedentary grazing (FSNG, TSRG, and SG, respectively). The results indicated that FSNG pastures exhibited the largest number of plant species while FSNG and TSRG pastures exhibited relatively high importance values for the primary dominant species. Carex duriuscula, Chenopodium glaucum, and Cleistogenes squarrosa were prominent in SG pastures, with C. duriuscula having the largest importance value. The mean height, cover, and aboveground biomass of plant communities in FSNG were significantly higher than those in SG (p &lt; 0.05), with no significant difference observed between FSNG and TSRG. FSNG also demonstrated the highest Shannon–Wiener, Simpson, and Pielou indexes. The Shannon–Wiener and Simpson indexes between the FSNG, TSRG, and SG pastures showed significant differences (p &lt; 0.05). Nomadic plant communities displayed positive loosely interspecific traits, suggesting independence and positive succession. Conversely, communities in TSRG and SG exhibited negative correlations and higher instability. The stability analysis ranked community stability as FSNG &gt; TSRG &gt; SG, suggesting that judicious grazing practices could enhance grassland stability. The findings reveal that grazing patterns influence plant community composition and function and that FSNG pastures promote higher species diversity, perennial dominance, and overall stability compared with TSRG and SG pastures.