Spring Ephemeral Research Articles

The ‘fertilizer island effect’ cannot eliminate competition between leguminous shrubs and symbiotic herbs in desert ecosystems

The ‘fertilizer island effect’ — a phenomenon engendered by shrubs — promotes the growth of symbiotic herbs and the stabilization of community structures in scrublands. Specifically, leguminous shrubs contribute significantly to the nitrogen input in desert ecosystems. However, the impact of these inputs on the nutrient balance in symbiotic herbs has seldom been explored. To enhance our understanding of the nutrient balance between nitrogen-fixing legume shrubs and symbiotic non-legume herbaceous plants in desert ecosystems, we focused on a typical legume shrub (Eremosparton songoricum) that grows in the Gurbantunggut Desert of northern China. Subsequently, we examined the biomass, ecological stoichiometry, and rhizosphere soil properties of two plant species (annual plant: Ceratocarpus arenarius; and ephemeral plant: Centaurea pulchella) growing across four horizontal distance ranges from E. songoricum. The results indicated that the closer a herbaceous plant was to the leguminous shrubs, the lower was its biomass and nutrient content. In contrast, herbaceous plants growing further away from the shrubs exhibited better growth conditions. The total biomass of Cer. arenarius and Cen. pulchella was greatest at a distance of D4 (90–100 cm), being 3.07, 2.15, and 1.23 times higher for Cer. arenarius and 2.05, 1.18, and 1.26 times higher for Cen. pulchella compared to distances of D1 (0–10 cm), D2 (30–40 cm), and D3 (60–70 cm), respectively. Meanwhile, the physicochemical properties of the rhizosphere root varied inversely with distance, with nutrient levels decreasing horizontally from D1 to D4 and vertically from 0–5 cm > 5–10 cm > 10–20 cm, showcasing a distinct ‘fertilizer island effect’. As the distance increased, the above-ground and below-ground parts of the symbiotic non-leguminous plants started to rely on different types of soil nutrients from different depths to maximize nutrient acquisition. According to the structural equation model, although soil fertility was higher closer to the central leguminous plants, the biomass of nearby herbaceous plants was lower. In summary, in desert ecosystems, the competitive dynamics exerted by leguminous shrubs significantly overshadowed the nutrient provisioning role of the ‘fertilizer island effect’. Furthermore, the utilization of nutrients by symbiotic non-leguminous plants did not exhibit species-specific patterns, and the dominant shrub continued to play a pivotal role. The evidence from this study promotes a deeper understanding of species coexistence mechanisms and ecological stability in desert environments.

Between-year weather differences and long-term environmental trends both contribute to observed vegetation changes in a plot resurvey study.

Repeated surveys of vegetation plots offer a viable tool to detect fine-scale responses of vegetation to environmental changes. In this study, our aim was to explore how the species composition and species richness of dry grasslands changed over a period of 17 years, how these changes relate to environmental changes and how the presence of spring ephemerals, which may react to short-term weather fluctuations rather than long-term climatic trends, may influence the results. A total of 95 plots was surveyed in 2005 and resurveyed in 2022 in dry grasslands of the Kiskunság Sand Ridge (Hungary, Eastern Central Europe), where there has been a significant increase in mean annual temperature during the last decades, while no trends in precipitation can be identified. Db-RDA was performed to reveal compositional changes. The changes in environmental conditions and naturalness state were assessed using ecological and naturalness indicator values. We also compared per-plot richness of all species, native species and non-native species of the old and the new relevés. All analyses were repeated after removing all spring ephemerals. We found clear temporal changes in species composition. Mean temperature indicator values increased, while mean soil moisture indicator values decreased during the 17 years. Also, decreasing per-plot richness was detected both for all species and for native species, while mean naturalness increased. After the removal of spring ephemerals, the compositional changes were less obvious although still significant. The increase in the temperature indicator values remained significant even without the spring ephemerals. However, the decrease in the moisture indicator values, the decrease in the number of all species and native species, as well as the increase in naturalness indicator values disappeared when spring ephemerals were excluded from the analyses. Our study demonstrates that between-year weather differences and long-term environmental trends both contribute to observed vegetation changes.

Distribution, species richness, and relative importance of different plant life forms across drylands in China

Studies on plant diversity are usually based on the total number of species in a community. However, few studies have examined species richness (SR) of different plant life forms in a community along large-scale environmental gradients. Particularly, the relative importance (RIV) of different plant life forms in a community and how they vary with environmental variables are still unclear. To fill these gaps, we determined plant diversity of ephemeral plants, annual herbs, perennial herbs, and woody plants from 187 sites across drylands in China. The SR patterns of herbaceous plants, especially perennial herbs, and their RIV in plant communities increased with increasing precipitation and soil nutrient content; however, the RIV of annual herbs was not altered along these gradients. The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality. The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments. An obvious shift emerged in plant community composition, SR and their critical impact factors at 238.5 mm of mean annual precipitation (MAP). In mesic regions (> 238.5 mm), herbs were the dominant species, and the SR displayed a relatively slow decreasing rate with increasing aridity, which was mediated mainly by MAP and soil nutrients. In arid regions (< 238.5 mm), woody plants were the dominant species, and the SR displayed a relatively fast decreasing rate with increasing aridity, which was mediated mainly by climate variables, especially precipitation. Our findings highlight the importance of comparative life form studies in community structure and biodiversity, as their responses to gradients differed substantially on a large scale.

Mountain-Xerophytic Vegetation Type Found in Daridag

Information about the mountain-xerophytic type of vegetation of the Daridag area is presented. Areas at an altitude of 1200-1600 m above sea level are characterized by plant species with mountain xerophytic vegetation. Mountain xerophytic flora is not homogeneous and represents a set of individual phytocenosis. Ephemeral plants play an important role in this vegetation. In addition to ephemerals, the vegetation includes bulbous, tuberous, and various grasses, mainly: Rhamnus pallasii Fisch. &amp; C. A. Mey., Astragalus microcephalus Willd., Astragalus beckerianus Trautv., Astragalus aduncus Willd., Thymus kotschyanus Boiss. &amp; Hohen., T. collinus M. Bieb.,Euphorbia seguieriana Neck., Caragana grandiflora (M. Bieb.) DC., Atraphaxis spinosa L., Acanthophyllum mucronatum C. A. Mey., Zygophyllum atriplicoides Fisch. &amp; C. A. Mey., Z. fabago L., Acantholimon araxanum Bunge etc. In total, the study identified 6 groups of formations and 16 associations. These include thorn shrubs, monodominant tragacanth xerophytic shrubs, cushion xerophytic shrubs, subshrub phrygana and mixed shrubs, which are included in the mountain xerophytic vegetation type. The phytocenosis of mixed herbaceous shrubs is comprised of 35 species, of which 10 species are shrubs (28.56%), 1 species is a semi-shrub (2.86%), 1 species is a shrub (2.86%), 2 species are semi-shrubs (5.72%), and 21 species are perennial and biennial (60%) plants. With regard to their life forms, of the 21 species included in the monodominant tragacanth xerophytic shrub grouping, three species are shrub-like, two species are shrubs, two species are semi-shrubs, and 14 species are perennial grasses.

Redistribution of Hydrothermal Resources on Different Elements of the Microrelief of Soils in the Semi-desert Zone and Agrolandscapes under Wheat

In the semi-desert regions of Azerbaijan there are habitats with varying elevations of only a few tens of centimeters. The zonal soils on the territory of the massif are gray-brown soils. Gray-brown soils develop under ephemeral plant cover. The soil is carbonate throughout the entire profile. Below the carbonate horizon lies a layer enriched with sulfates in the form of veins of crystalline gypsum. The content of absorbed sodium in the gray-brown soils of the deluvial plain of the Siyazan-Sumgait massif is 30-50% of the number of absorbed bases in the Solonetz-Columnar soil horizon. The amount of humus in the upper layers of the soil fluctuates between 1-2%, towards the bottom it sharply decreases. In studies carried out on gray-brown soils of the Siyazan-Sumgait massif, hydrothermal potential indicators vary within the range of 426-552 m3/ha. The distribution of temperature and humidity in depth in the soil under wheat differs from the natural habitat. In the arable layer, the temperature is evenly distributed throughout the entire profile, while the humidity gradually increases in the lower layers. The influence of the hydrothermal regime on wheat yield was: 2022 — 24.0-30.0 cwt/ha; 2023 — 16.0-24.5 cwt/ha.

Evaluating the definition and distribution of spring ephemeral wildflowers in eastern North America.

The herbaceous layer accounts for the majority of plant biodiversity in eastern North American forests, encompassing substantial variation in life history strategy and function. One group of early-season herbaceous understory species, colloquially referred to as spring ephemeral wildflowers, are ecologically and culturally important, but little is known about the prevalence and biogeographic patterns of the spring ephemeral strategy. We used observations collected by the Global Biodiversity Information Facility (GBIF) to quantify the ephemerality of 559 understory forb species across eastern North America and classify them according to a continuous ephemerality index (ranging from 0 = never ephemeral to 1 = always ephemeral). We then used this information to model where ephemeral forbs were most common across the landscape with the goal of identifying geographic and environmental drivers important to their distributions and ranges. Only 3.4% of all understory wildflower species were spring ephemerals in all parts of their range, and 18.4% (103 species) were ephemeral in at least part of their range. Spring ephemerals peaked in absolute species richness and relative proportion at mid latitudes. Spring ephemeral phenology is an important shade-avoidance strategy for a large segment of the total understory species in temperate deciduous forests. In North America, the strategy is relatively most important for forest understories at mid latitudes. The definitions of spring ephemerality we provide here serve as an important ecological context for conservation priorities and to evaluate responses of this biodiverse group to future environmental change.

New records of forty-nine herbaceous plant species from lateritic plateaus for Ratnagiri District of Maharashtra, India

Ratnagiri is a coastal district and a part of Konkan region of Maharashtra. During our floristic studies on ephemeral and herbaceous plants of lateritic plateaus of Ratnagiri district from year 2020 to 2022, we have collected 49 herbaceous and ephemeral flowering plant species new addition to the Ratnagiri district. Newly added above said plant species belonging to 19 families and among them 16 species are endemic to India. This paper provides detailed checklist with herbarium specimen numbers for all the collected species and photographs of 16 endemic species.

Dynamic transcriptome analysis provides molecular insights into underground floral differentiation in Adonis Amurensis Regel & Radde

Understanding flower developmental processes is a prerequisite for improving flowering ‘plants’ production. Adonis amurensis is a fascinating spring ephemeral plant that develops its flower organs underground. Nevertheless, knowledge of the molecular mechanisms driving this particular process is scarce. Herein, we examined transcriptional changes during underground flower differentiation in A. amurensis and unveiled key differently regulated genes and pathways. High-throughput RNA sequencing of meristems at different flower developmental stages, including flower primordium (FP), sepal stage (SE), perianth primordium (PE), stamen stage (ST), and pistil stage (PI), identified 303,234 unigenes that showed 44.79% similarity with sequences in Aquilegia coerulea. Correlations, principal component, and differentially expressed genes (DEGs) analyses revealed that few molecular changes occurred during the transition from PE to ST. Many DEGs exhibited stage-specific regulations. Transcription factor (TF) and phytohormone family genes are critical regulators of the floral differentiation process in A. amurensis. The most differentially regulated TFs were MADS, FAR1, MYBs, AP2/ERF, B3, C2H2, and LOBs. We filtered out 186 candidate genes for future functional studies, including 18 flowering/circadian-related, 32 phytohormone-related, and TF family genes. Our findings deepen our understanding of the underground flower differentiation process and offer critical resources to dissect its regulatory network in A. amurensis. These findings establish a foundational platform for researchers dedicated to exploring the unique phenotypic characteristics of this specific flowering modality and delving into the intricate molecular mechanisms underpinning its regulation and expression.

The evolution of ephemeral flora in Xinjiang, China: insights from plastid phylogenomic analyses of Brassicaceae

BackgroundThe ephemeral flora of northern Xinjiang, China, plays an important role in the desert ecosystems. However, the evolutionary history of this flora remains unclear. To gain new insights into its origin and evolutionary dynamics, we comprehensively sampled ephemeral plants of Brassicaceae, one of the essential plant groups of the ephemeral flora.ResultsWe reconstructed a phylogenetic tree using plastid genomes and estimated their divergence times. Our results indicate that ephemeral species began to colonize the arid areas in north Xinjiang during the Early Miocene and there was a greater dispersal of ephemeral species from the surrounding areas into the ephemeral community of north Xinjiang during the Middle and Late Miocene, in contrast to the Early Miocene or Pliocene periods.ConclusionsOur findings, together with previous studies, suggest that the ephemeral flora originated in the Early Miocene, and species assembly became rapid from the Middle Miocene onwards, possibly attributable to global climate changes and regional geological events.

Spatio-temporal variation of species richness and phylogenetic diversity patterns for spring ephemeral plants in northern China

Understanding the spatiotemporal distribution of species diversity in response to climatic change is essential for the conservation and management of species resources. Spring ephemeral plants (SEs) have played a crucial role in sustaining the desert and woodland ecosystems of northern China. However, our knowledge regarding the spatiotemporal variation of species diversity in SEs is limited. In this study, we employed occurrence and phylogenetic data for 200 SEs, alongside 19 environmental variables, to model their geographical distribution during the Last Glacial Maximum (LGM), Current, and the year 2070 (considering two representative concentration pathway scenarios, SSP2–4.5 and SSP5–8.5). We also visualized the phylogenetic diversity patterns in the Current. Our findings revealed that more than half of the SEs notably expanded their range and continuously shifted northeastward from LGM to 2070. From LGM to Current and from Current to SSP2–4.5_2070, 64% and 54% of SEs shifted from higher to lower elevations, and 53% of them will slightly shift to higher elevations from Current to SSP5–8.5_2070. We identified three distinct bioregions corresponding to the core ranges of desert SEs and understory SE ecotypes. The Ili Valley, Tacheng Basin, northern and southern Junggar Basin, and Changbai Mountains were identified as hotspots for species richness, phylogenetic diversity, and endemism for the two SE ecotypes. Notably, these hotspots had limited overlap with existing nature reserves. Additionally, the suitable habitat of desert SEs was primarily determined by precipitation seasonality and precipitation of driest month, whereas the distribution of forest understory SEs was mainly influenced by annual precipitation and temperature seasonality. This study significantly contributes to a comprehensive understanding of the modern diversity distribution patterns and conservation priorities for SEs within a species distribution and phylogenetic framework.

Interannual variation in spring weather conditions as a driver of spring wildflower coverage: a 15-year perspective from an old-growth temperate forest.

Spring ephemerals are wildflowers found in temperate deciduous forests that typically display aboveground shoots for a period of 2 months or less. Early spring, before the canopy leaves out, marks the beginning of the aboveground growth period where ephemerals acquire nutrients and resources via aboveground tissues. Several studies have shown that spring ephemeral reproduction is affected by spring temperature, but few have looked at how weather conditions of the current and previous seasons, including precipitation and temperature, influence aboveground growth. Here, we examine the response of a spring ephemeral community in a temperate hardwood forest to weather conditions during their current and previous growing seasons. For 15 years we estimated percent cover of each species within our community. We highlighted five dominant spring ephemerals within this community: wild leek (Allium tricoccum), cutleaf toothwort (Cardamine concatenata), spring beauty (Claytonia virginica), squirrel corn (Dicentra canadensis) and trout lily (Erythronium americanum). We compared changes in cover on both a community and species level from 1 year to the next with average precipitation and temperature of the year of measurement as well as the year prior. We found precipitation and temperature influence a change in cover at the community and species level, but the strength of that influence varies by species. There were few significant correlations between plant cover in the current year and temperature and precipitation in the 30 days preceding measurement. However, we found significant correlations between plant cover and precipitation and temperature during the previous spring; precipitation and cover change were positively correlated, whereas temperature and cover change were negatively correlated. Overall, cooler, wetter springs lead to an increase in aboveground cover the next year. Learning how individual species within a forest plant community respond to weather conditions is a crucial part of understanding how plant communities will respond to climate change.

Rodent disturbances in arid regions drive ephemeral plant diversity but deteriorate soil health

The desert ecosystem is an important ecological barrier to prevent desertification and maintain the stability of arid zone ecosystem and regional security. The degree of change and species composition of pioneer species during the early spring recovery of the community can be used as important indicators of regional ecology and to predict subsequent ecological stability in the early spring. Rodents serve as ecological engineers in the ecosystem through their behavior, and they influence the composition of biological communities. In this study, we analyzed the correlations between soil physicochemical properties, community assembly, plant diversity and microbial diversity in the areas disturbed by gerbils (RD) and those not disturbed by gerbils (CK) with ephemeral plants in the arid zone and comprehensively evaluated the soil quality (SQI) and ecosystem sustainability (SI). The results showed the following: (1) soil nutrients within the two different areas were significantly different owing to disturbance, and the biodiversity in the RD was greater than that in the CK, but there was low homogeneity; (2) There were significant differences in plant diversity and microbial diversity within the two different; (3) The correlation analysis of community assembly showed that the niche width of the community in RD was higher and the community composition was more affected by deterministic factors, while that in CK was the opposite; and (4) The analytical results showed that the SI and SQI in the RD were smaller than those in the CK. In conclusion, disturbance by rodents enhances biodiversity in arid areas but detrimental to the long-term development of communities. Therefore, it is important to explore the rational use of disturbance relationships to “complement the strengths and weaknesses,” provide a theoretical basis for future reasonable control of disturbance, maintain the ecological development of arid areas, and improve the ecological stability of desert arid regions.

The effect of moisture on nitrogen acquisition strategies of ephemeral desert plants in north-western China are regulated by temperature

AimsSymbiotic plants achieve partitioning of shared resources by chemical nutrient niche separation to escape competition. Understanding whether the nitrogen(N) nutrient acquisition strategies of ephemeral plants are influenced by temperature and moisture can facilitate the elucidation of plant coexistence strategies in desert ecosystems under environmental change. This study aimed to see whether changes in temperature and moisture affected the preferential uptake of different N chemotypes by ephemerals. MethodsIn this study, four dominant ephemerals in the Gurbantunggut Desert, Eremopyrum orientale, Erodium oxyrhinchum, Centaurea pulchella, and Lappula patula, were selected for controlled experiments in indoor pots. We conducted a short-term 15N follow-up experiment on potted treatments by setting two temperature gradients (low temperature(T1): 15 °C during the day and 5 °C at night; high temperature(T2): 25 °C during the day and 15 °C at night) and three moisture gradients (drought treatment(W1): soil moisture content of 2%; normal moisture treatment(W2): soil moisture content of 8%; wet treatment(W3): soil moisture content of 14%). Results Four ephemerals preferentially absorbed 15N-NH4 at low temperature treatment (T1), with a contribution ranging from 17.33% to 55.11%. The greatest uptake rate of 15N-NH4 was at the low temperature-normal moisture treatment (T1W2), and the fastest N uptake rate among the four plants could reach 13.84 μg·h–1, while at the high temperature-drought treatment (T2W1), the uptake was the smallest. However, plants showed the greatest preference for 15N-NO3 uptake at the high temperature treatment, with contributions ranging from 16.09% to 54.06%. The uptake rate of 15N-NO3 was greatest at the high temperature-wet treatment (T2W3), where the fastest N uptake rate among the four plants could reach 12.48 μg·h–1, and the smallest rate of 15N-NO3 at the low temperature-drought treatment (T1W1). The four ephemerals could also absorb organic N, 15N-Glycine, especially at the low temperatures. ConclusionsThe results showed that the four plants exhibited “Plasticity” in the uptake of the three N forms under different hydrothermal conditions. The effect of temperature and moisture interaction is more reflective of the N acquisition pattern of ephemeral plants in the desert. In low temperature environments, the uptake preference of ephemerals for N forms was mainly regulated by water, while in high temperature environments, the uptake of N forms by ephemerals was mainly regulated by temperature.

Loss of native herbivores triggers diversity decline of ephemeral plant communities

AbstractAimEvaluate the temporal changes in species diversity, composition, and structure of ephemeral plant communities and the seed bank in response to long‐term herbivore exclusion over 11 years in plots with and without herbivores.LocationNorth‐central Chile.MethodsWe obtained information on ephemeral vegetation cover in August and September using the intercept point method and recorded seed abundance in April. The Bosque Fray Jorge National Park Long‐Term Socio‐Ecological Research (LTSER) provided these records covering 11 years (2009–2019). From the original experiment of 20 plots, we used eight plots divided into two treatments: four plots allowed free access to all herbivores (with herbivores), while the other four plots excluded herbivores (without herbivores).ResultsWe found that Hill–Shannon diversity increased in plant communities with herbivores and a temporal increase in the cover of the dominant species, Plantago hispidula, under herbivore exclusion. In wet years, species richness and temporal turnover of plant communities increased independently of treatment. Although seed abundance differed among treatments and years, population structure remained constant over time and among treatments, suggesting that the seed bank acts as a buffer against shocks that modify plant community dynamics. Structural equation modeling revealed that precipitation, via its positive effects on Plantago hispidula, increases native plant richness to a greater extent than herbivores. However, in the absence of herbivores, precipitation directly affects native species richness. Moreover, we found that precipitation also influences the native species richness of the seed bank, both directly and indirectly, although its impacts exhibit a time lag.ConclusionsOur study demonstrates that the temporal dynamics of ephemeral plant communities and seed banks in semi‐arid ecosystems are strongly coupled to climate variability, highlighting the vulnerability of these communities to biodiversity loss and climate change.

Morphological, physiological and metabolomic analysis to unravel the adaptive relationship between root growth of ephemeral plants and different soil habitats

To gain insights into the adaptive characteristics of ephemeral plants and enrich their potential for resource exploitation, the adaptive changes in two highly dominant species (Malcolmia scorpioides and Isatis violascens) to soil habitats (aeolian soil, AS; grey desert soil, GS) were investigated from the aspects of root morphology, physiology, and metabolism in this study. The results revealed that changes in root morphology and enzyme activity were affected by soil habitat. Total root length (TRL), root volume (RV) and root surface area (RSA) were higher in GS than in AS. The levels of proline (Pro), glutathione (GSH), soluble sugar (SS), and lysine (Lys) were higher in GS than in AS. Untargeted LC–MS metabolomics indicates that root metabolites of both species differed among the two soil habitats. Root responses to different soil habitats mainly affected some metabolic pathways. A total of 780 metabolites were identified, common differential metabolites (DMs) in both species included amino acids, fatty acids, organic acids, carbohydrates, benzene and derivatives, and flavonoids, which were mainly involved in carbohydrate metabolism, amino acid metabolism, flavonoid biosynthesis and fatty acid metabolism, and their abundance varied among different habitats and species. Some key DMs were significantly related to root morphology and enzyme activity, and indole, malonate, quercetin, uridine, tetrahydroharmine, and gluconolactone were important metabolites associated with root growth. Therefore, the response changes in root growth and metabolite of ephemeral plants in response to soil habitats reflect their ecological adaptation, and lay a foundation for the exploitation of plant resources in various habitats.

More effect of ephemeral plant species diversity on aboveground biomass than functional diversity and functional composition

AbstractThe quantification of plant diversity–productivity relationships is essential for accurate productivity assessments. Global change drivers are altering resource availability and biodiversity. However, the extent to which multiple attributes of diversity (species, functions) buffer community productivity in response to the resource availability changes and the potential driver mechanisms of the diversity‐productivity relationship still needs to be the consensus. We investigated the ephemeral plant diversity–productivity relationships of different attributes along a precipitation gradient in the Gurbantunggut Desert, China. To evaluate the potential mechanisms by which diversity and functional composition affect aboveground productivity (niche complementarity and selection effect). Our results showed that (1) the variance of species richness (SR), Rao's quadratic entropy (RaoQ), community‐weighted mean of height (CWMH), and community‐weighted mean of leaf phosphorus concentration (CWMP) was larger among sites (variation between different sites) than subplots (variation between different subplots). Among subplots, the variance of community‐weighted mean of specific leaf area (CWMSLA), community‐weighted mean of leaf carbon concentration (CWMC), and community‐weighted mean of leaf nitrogen concentration (CWMN) was larger than the sites. (2) SR, RaoQ, CWMC, CWMN, CWMH, pH, and mean annual precipitation (MAP) collectively influenced the accumulation of aboveground biomass (AGB). (3) Species diversity and MAP have strongly affected AGB and accounted for 50% and 42%. The study confirms that SR is the optimal predictor of biomass in ephemeral plants. Complementation effects may be the primary mechanism explaining the relationship between biodiversity and productivity in the Gurbantunggut Desert, and thus the effect of plant diversity cannot be downplayed.

Responses of Ephemeral Plants to Precipitation Changes and Their Effects on Community in Central Asia Cold Desert.

In the context of global climate change, changes in precipitation patterns will have profound effects on desert plants, particularly on shallow-rooted plants, such as ephemeral plants. Therefore, we conducted an experiment on artificial control of precipitation for four dominant ephemeral plants, Erodium oxyrhinchum, Alyssum linifolium, Malcolmia scorpioides, and Hyalea pulchella, in the southern edge of Gurbantunggut Desert. We measured the importance value and some growth parameters of the four species under increased or decreased precipitation and constructed trait correlation networks for each of the four species. We also compared the response of increased or decreased precipitation to vegetation coverage. The results show that drought significantly reduced the survival rate, seed production and weight, and aboveground biomass accumulation of ephemeral plants. The four ephemeral plants showed different tolerance and response strategies to precipitation changes. E. oxyrhinchum and M. scorpioides can avoid drought by accelerating life history, and E. oxyrhinchum, A. linifolium, and H. pulchella can alleviate the negative effects of drought by adjusting leaf traits. However, the response of different species to the wet treatment was not consistent. Based on the results of the trait correlation network, we consider A. linifolium belongs to the ruderal plant, E. oxyrhinchum and M. scorpioides belong to the competitive plants, and H. pulchella belongs to the stress-tolerant plant. The outstanding trait coordination ability of E. oxyrhinchum makes it show absolute dominance in the community. This indicate that ephemeral plants can adapt to precipitation changes to a certain extent, and that distinct competitive advantages in growth or reproduction enabled species coexistence in the same ecological niche. Nevertheless, drought significantly reduces their community cover and the ecological value of ephemeral plants. These findings established the basis to predict vegetation dynamics in arid areas under precipitation changes.

Effects of drought treatment on photosystem II activity in the ephemeral plant Erodium oxyrhinchum

Effects of drought treatment on photosystem II activity in the ephemeral plant Erodium oxyrhinchum

Erodium oxyrhinchum sustains severe drought stress by maintaining stable photosynthetic electron transport under progressive drought conditions

Drought is a key environmental factor limiting the growth and development of desert plants. In this experiment, we investigated the response of photosynthesis in the ephemeral plant E. oxyrhinchum to progressive drought conditions in its natural habitat. In response to drought stress, the mechanism for photosynthesis regulation in E. oxyrhinchum is switched from stomatal to non-stomatal limitations. One notable characteristic of E. oxyrhinchum is its ability to sustain photosynthesis under severe drought conditions. This is because the transition from stomatal to non-stomatal limitation occurred at a much lower leaf water content (56.51% ± 8.53%), compared to that in other plant species. With the drought treatment, the net photosynthetic rate was maintained or even increased to a much higher value to that of the control (33.65 ± 1.72 vs. 17.65 ± 2.35 μmol CO2 m-2s-1), which coincided with the increased stomatal conductance. During the entire stomatal limitation to the photosynthesis stage, the maximum photochemical efficiency of photosystem II (Fv/Fm) remained unchanged. Additionally, the prompt Chl a fluorescence induction was stable, which indicated an intact photosystem II structure and a balanced redox state of the plastoquinone pool. The variation partition analysis revealed that the substantial increase in antioxidant activities and sensitive response to nonphotochemical quenching during this stage contributed significantly to maintaining a stable Fv/Fm value. To conclude, we have not only provided novel information regarding the drought-escape E. oxyrhinchum species but also concluded that PSII activity modulates the switch from stomatal to non-stomatal photosynthesis limitation under progressive drought conditions.

Potential distribution of the spring ephemeral plant Adonis amurensis in Northeast China under future climate change

AbstractAdonis amurensis Regel et Radde is an early spring plant in northeastern China that has great ornamental value because it blooms before other plants have sprouted. It has not been used to its full potential due to environmental restrictions on its growth. It will be extremely important for its application to comprehend the possible habitat of A. amurensis and the critical environmental factors controlling its distribution under current and future climatic scenarios. In this work, two climate change scenarios of 2041–2060 and 2081–2100 were utilized to predict the suitable habitat of A. amurensis. The results showed that the suitable habitat was mainly distributed along the Changbai Mountains, with a total area of 303,090 km2, and the potential and high‐potential habitat area were 141,218 and 161,872 km2, respectively. In the future climate scenarios, the suitable habitat of A. amurensis was still distributed along the Changbai Mountains, but the area was reduced. In ssp126 and ssp585 scenarios of 2041–2060 and 2081–2100, the area was reduced by 7.13% and 22.34% and 18.66% and 8.09%, respectively. The reduced suitable habitat was mainly located in central Heilongjiang (southeastern Xiao Xing'an Ling), central Jilin, and northeastern Liaoning. The suitable habitat was significantly influenced by precipitation, mainly affected by annual precipitation, followed by precipitation seasonality, soil surface pH, and slope. The results of this study can serve as empirical support for the artificial cultivation, ecological restoration, and long‐term use of A. amurensis.