Loss Of Plant Diversity Research Articles

Nutrient effects on plant diversity loss arise from nutrient identity and decreasing niche dimension.

Two hypotheses have been used to explain the loss of plant diversity with nutrient addition. The nutrient identity hypothesis posits that biodiversity loss is due to a specific limiting nutrient, such as nitrogen (N) or phosphorus (P), while the niche dimension hypothesis posits that adding a larger number of limiting nutrients, regardless of their identity, results in biodiversity loss. These two hypotheses have not previously been tested together simultaneously. Here, we conduct that analysis to enable their relative effect sizes to be compared. We manipulated the supply of eight nutrients in the same experimental meadow grassland site to isolate the effects of the identity of added nutrients versus the number of added nutrients on biodiversity loss. We found support for both hypotheses, with the largest negative effects on biodiversity measures being due to N, or N and P treatment, with additional more minor effects of the number of added nutrients. Structural equation models (SEMs) suggested both identity and number of added nutrients had direct negative effects on biodiversity, likely caused by species' innate ability to competitively respond to nutrients, especially in response to disease, herbivory, and stress. SEMs also suggested indirect effects arising from nutrient-driven increases in aboveground biomass, which resulted in intensified competition for light and the competitive exclusion of short-statured species. These effects were exacerbated by the nutrients N and P which caused a shift in biomass accumulation from belowground to aboveground. The results highlight that a multi-nutrient perspective will improve our ability to effectively manage, monitor, and restore ecosystems.

Soil community history strengthens belowground multitrophic functioning across plant diversity levels in a grassland experiment

Biodiversity experiments revealed that plant diversity loss can decrease ecosystem functions across trophic levels. To address why such biodiversity-function relationships strengthen over time, we established experimental mesocosms replicating a gradient in plant species richness across treatments of shared versus non-shared history of (1) the plant community and (2) the soil fauna community. After 4 months, we assessed the multitrophic functioning of soil fauna via biomass stocks and energy fluxes across the food webs. We find that soil community history significantly enhanced belowground multitrophic function via changes in biomass stocks and community-average body masses across the food webs. However, variation in plant diversity and plant community history had unclear effects. Our findings underscore the importance of long-term community assembly processes for soil fauna-driven ecosystem function, with species richness and short-term plant adaptations playing a minimal role. Disturbances that disrupt soil community stability may hinder fauna-driven ecosystem functions, while recovery may require several years.

Field margin management for promoting plant diversity—A functional approach to investigating the effects of multiple measures on plant community dynamics

Strategies to counteract the loss of arable plant diversity often target field margins. Yet there is still need for research on how arable plant diversity is impacted by the type, scale and diversity of margin management. To assess this experimentally, we combined five measures imposing different disturbance regimes (flower-strip mown twice a year, tilling in spring or autumn, adding sand as substrate, and frequent mowing as a control) at two spatial scales.We explored how plant community dynamics are affected by both single measures and their combination. We addressed four hypotheses: H1) single measures shift community weighted mean (CWM) values of functional traits and reduce the within-measure community weighted standard deviation (CWSD) of these traits; H2) heavy disturbance (early tilling and sand) causes taxonomic and functional diversity (alpha-diversity) to increase over time; H3) combining different measures increases dissimilarity (beta-diversity) and thus gamma-diversity across measures; and H4) increased spatial heterogeneity of measures promotes all levels of diversity.We found shifts in CWM and reduced CWSD in flower-strips (smaller seed mass, perennial lifespan) and late-tilling (later flowering-onset) whereas sand and early-tilling tended to increase CWSD (H1). Trends across measures indicate shifts towards species with competitive strategies (H1). Compared to frequently mown controls, heavy disturbance (sand and early-tilling) promoted alpha-diversity over time, despite lower initial diversity. Moderate disturbance (flower-strip, late tilling) initially promoted alpha-diversity, but diversity then did not increase further (H2). Combining different measures promoted diversity compared to single measures, but the similarity between measures increased over time (H3). Scale played a minor role in determining community-composition (H4).Disturbance regimes imposed by different management of field margins shape the functional composition of arable plant communities. Strategies combining different measures help to balance initial benefits of moderate disturbance with the longer-term diversity gains from heavier disturbance.

The relative importance of nitrogen deposition and climate change in driving plant diversity decline in roadside grasslands

Nitrogen deposition and climate change have been identified as major threats to the biodiversity of semi-natural grasslands. Their relative contribution to recent biodiversity loss is however not fully understood, and may depend on local site conditions such as soil type, which hampers efforts to prevent further decline. We used data from >900 permanent plots in semi-natural grasslands in Dutch roadsides to investigate whether trends in plant diversity and community composition (2004–2020) could be explained by: (1) nitrogen deposition (NHx and NOy) and climate change (winter degree days and summer drought), (2) the interactive effect of nitrogen deposition and climate change, and (3) the interactive effect of nitrogen deposition and climate change with soil type. Overall we observed a decline in plant diversity and an increased dominance of tall species and grasses. These changes were linked to winter warming, but not to changes in summer drought and nitrogen deposition. The effect of winter warming was more pronounced in areas with higher NOy deposition, but was consistent across different soil types. Our results suggest that winter warming will become an important driver of plant diversity loss by altering competitive interactions, which could have major repercussions for other trophic levels and ecosystem services. Future conservation and restoration of grassland biodiversity therefore requires management regimes that are adapted to winter warming.

Holocene landscape changes in response to sea level oscillations and agricultural intensification in a coastal plain of southeastern South America

This study identified landscape changes in response to variations in mean sea level (MSL) and anthropogenic intervention, from the Early to Late Holocene in Southestern South America. Ananalysis based on palynology and sedimentary bacterial DNA from two sediment cores from the Patos-Mirim System (PMS) is introduced for the first time, to achieve an integrated paleoenvironmental and ladscape reconstruction. The data indicated an east-west migration of the freshwater and forest environments set in the lowlands during the transgressive period (6000–5000 cal yr BP) and an increase in external total biomass input during this MSL rise. A consolidated vegetation onset was inferred, especially of forest environments, after the Holocene Climatic Optimum (5000 cal yr BP). During the last century, landscape changes especially associated with anthropogenic factors were clearly identified from the palynological assemblages. That is, an alternation between Poaceae and Cyperaceae, the first occurrence of Pinus spp. and an increase in the influx of herbs and trees flagged the increase in cultivated areas due to the agricultural and agroforestry intensification. Extreme values of palynological influx appear to be a good proxy for the impact of El Niño events on the sedimentary record, which were associated to increased precipitation. The study also clearly demonstrates the high environmental stress generated by human activities, e.g. loss of plant diversity and changes in the bacterial abundance due to the higher agrochemicals input.

PaRaVis: An automatic Python graphical package for ensemble analysis of plant beta diversity using remote sensing proxies

The ongoing impacts of climatic changes, coupled with intensified human activities, are leading to a significant loss of plant diversity, prompting urgent calls for comprehensive monitoring of forest ecosystems. This is particularly concerning in regions with the encroachment of human activities into forest zones, and inadequate regulations that primarily view forests as a source of timber without fully accounting for their critical roles in biodiversity. These issues highlight the need for effective geospatial approaches to support conservation strategies and sustained monitoring of plant diversity. The majority of remote sensing studies of plant diversity have focused on alpha-diversity, while beta-diversity plays an important role in providing a comprehensive picture of biodiversity patterns across scales. Among various remote sensing proxies, Rao's Q index stands out as a reliable metric to quantify beta-diversity using multispectral remote sensing indices. However, a holistic approach that can incorporate multiple remote sensing indices and enable comparative analysis using graphical means with computational efficiency is lacking. In response, we developed PaRaVis, an open-source Python-based graphical package for deriving spectral diversity from multispectral remote sensing datasets as a proxy for functional diversity using Rao's Q index. This tool encompasses all the necessary steps for parallelized computation, visualization, and analysis of Rao's index from either single or multiple multispectral indices. It is capable of calculating and visualizing 75 vegetation indices (VIs), from a raster scene, followed by calculating Rao's Q both unidimensionally and multidimensionally in parallel. PaRaVis also offers features for visualizing, analyzing, and comparing Rao's Q outputs using statistical performance diagnostics. It provides a unique means to infer diversity patterns in space and time and is therefore invaluable for researchers or organizations involved with plant diversity monitoring, especially those with limited data analysis or computer programming experience. To demonstrate the tool's effectiveness, we analyzed plant diversity patterns using satellite-derived spectral heterogeneity measures in forest sites within the Hyrcanian Forests of Iran and sites located in Germany. The first case study focused on UNESCO Natural Heritage sites. Our analysis revealed that employing EVI, SR3, and TCI indices as inputs for the multidimensional Rao's Q yielded higher performance in monitoring more heterogeneous forests compared to the unidimensional mode. In the second case study, we utilized field Species Richness and Shannon-Wiener diversity indices to evaluate PaRaVis and our method. We found that using a multi-temporal, multi-index approach enhances the results compared to multi-seasonal and classical Rao based on single time.

Mechanisms of biodiversity loss under nitrogen enrichment: unveiling a shift from light competition to cation toxicity.

The primary mechanisms contributing to nitrogen (N) addition induced grassland biodiversity loss, namely light competition and soil cation toxicity, are often examined separately in various studies. However, their relative significance in governing biodiversity loss along N addition gradient remains unclear. We conducted a 4-yr field experiment with five N addition rates (0, 2, 10, 20, and 50 g N m-2 yr-1) and performed a meta-analysis using global data from 239 observations in N-fertilized grassland ecosystems. Results from our field experiment and meta-analysis indicate that both light competition and soil cation (e.g. Mn2+ and Al3+) toxicity contribute to plant diversity loss under N enrichment. The relative importance of these mechanisms varied with N enrichment intensity. Light competition played a more significant role in influencing species richness under low N addition (≤ 10 g m-2 yr-1), while cation toxicity became increasingly dominant in reducing biodiversity under high N addition (>10 g m-2 yr-1). Therefore, a transition from light competition to cation toxicity occurs with increasing N availability. These findings imply that the biodiversity loss along the N gradient is regulated by distinct mechanisms, necessitating the adoption of differential management strategies to mitigate diversity loss under varying intensities of N enrichment.

Current and future patterns of vascular plant species richness across a forest–grassland–desert transect in East Asia

AbstractQuestionsRapid climate change has profoundly altered the spatial distribution of terrestrial plants especially in arid and semi‐arid biomes. However, it remains poorly documented how climate shapes the current and future patterns of plant diversity within and across these vulnerable vegetation types.LocationParts of Mongolia, southeastern Russia, and northern China (94.78°–126.78°E, 34.60°–54.27°N).MethodsUsing a random forest model trained by a comprehensively compiled database on vascular plant species richness (i.e., the number of species within a defined plot area) and corresponding climate variables, soil conditions and vegetation types (forest, grassland, desert), we assessed the current pattern of vascular plant species richness across a typical forest–grassland–desert transect in East Asia. We further predicted future changes in vascular plant species richness under three climate scenarios (SSP1‐2.6, SSP3‐7.0, and SSP5‐8.5).ResultsVascular plant species richness generally showed a decrease from northeast to southwest across the transect, mainly explained by spatial variations in growing‐season precipitation and the minimum temperature of the coldest month. More than half of the transect area will likely experience a loss in vascular plant species richness in 2041–2070 under all three scenarios. The decrease in vascular plant species richness will likely occur in a smaller area under the low‐emission scenario (SSP1‐2.6). We also predict distinct changes in vascular plant species richness for different vegetation types, including a slight increase in forests but an overall decrease in both grasslands and deserts.ConclusionsOur findings suggest a dominant role of growing‐season precipitation in shaping the spatiotemporal patterns of vascular plant species richness across the forest–grassland–desert transect and highlight a risk of plant diversity loss in the regional dryland ecosystems in response to future climate change.

Palmitic Acid Synthesis from Coconut Oil Cake Waste using Probiotic Bacteria of Marine Fishes

Palmitic acid is used in cosmetics as well as skin care products, and its extraction from plants remains major source of production. The conventional process of extraction is quite laborious and may lead to loss of plant diversity. Therefore, the current investigation aims at producing palmitic acid from coconut oilcake using probiotics isolated from marine fish. A total of 18 bacterial strains were isolated from Indian oil Sardine fish (Sardinella longiceps) and Obtuse barracuda fish (Sphyraena obtusata). Among various strains isolated, Mm12 strain was able to synthesize 60.57 mg/100mL fatty acids. The production of palmitic acid was optimized using RSM with the most appropriate values of the tested parameters by using Design-Expert 13 to resolve the correlation coefficients binomial equation’s reciprocal matrix as temperature 10°C, pH 5.5, and 40 g oil cake substrate. The highest quantity of palmitic acid that could be produced under ideal circumstances has been estimated to be 19.97 mg/100 mL which was confirmed by GC–MS fatty acid methyl ester (FAME) analysis. Production of palmitic acids from the oil cake was not only a novel method of valorizing industrial waste using probiotic bacteria and but also a promising method of producing palmitate using cheaper substrates.

Short-term effects of understory removal on understory diversity and biomass of temperate forests in northeast China

IntroductionUnderstory removal is a traditional practice in forest management to reduce fire risk and promote seedling regeneration. However, its effect on understory diversity, biomass and soil nutrients in temperate forest ecosystems is less known, which limits our assessment of the effectiveness of understory vegetation management.MethodsWe quantified the composition of the understory species, their diversity, and the biomass of the understory and factors driving changes in these parameters in primary mixed broad-leaved Pinus koraiensis forest (BKF), secondary Betula platyphylla forest (BF), and Larix gmelinii plantation (LF) in northeast China after a 5-year understory removal.ResultsAfter understory removal, the number of shrub and herb species in BKF and LF decreased, while the number of shrub species in BF increased significantly and that of herb species decreased; the species with strong light preference, Equisetum hyemale, Impatiens noli-tangere, and Filipendula Palmata, were dominant in the herb layer of the three forest types; Shannon–Wiener diversity, Pielou evenness, and Simpson diversity of the herb layer in LF increased significantly (P < 0.05), while those of the shrub and herb layers in BF and LF showed no significant changes (P > 0.05). The total understory biomass of understory of BKF and LF decreased by 0.94 t·hm−2 and 1.32 t·hm−2, respectively, while that of BF increased by 1.31 t·hm−2; soil NH4+-N and total phosphorus (TP) were the key factors regulating understory vegetation diversity and biomass, respectively.ConclusionThese results suggest that understory removal is a beneficial management strategy for increasing shrub biomass and diversity in secondary forests, while it should be avoided in primary forests and plantations to prevent the reduction of understory plant diversity and soil nutrient loss.

A global meta-analysis on the effects of organic and inorganic fertilization on grasslands and croplands.

A central role for nature-based solution is to identify optimal management practices to address environmental challenges, including carbon sequestration and biodiversity conservation. Inorganic fertilization increases plant aboveground biomass but often causes a tradeoff with plant diversity loss. It remains unclear, however, whether organic fertilization, as a potential nature-based solution, could alter this tradeoff by increasing aboveground biomass without plant diversity loss. Here we compile data from 537 experiments on organic and inorganic fertilization across grasslands and croplands worldwide to evaluate the responses of aboveground biomass, plant diversity, and soil organic carbon (SOC). Both organic and inorganic fertilization increase aboveground biomass by 56% and 42% relative to ambient, respectively. However, only inorganic fertilization decreases plant diversity, while organic fertilization increases plant diversity in grasslands with greater soil water content. Moreover, organic fertilization increases SOC in grasslands by 19% and 15% relative to ambient and inorganic fertilization, respectively. The positive effect of organic fertilization on SOC increases with increasing mean annual temperature in grasslands, a pattern not observed in croplands. Collectively, our findings highlight organic fertilization as a potential nature-based solution that can increase two ecosystem services of grasslands, forage production, and soil carbon storage, without a tradeoff in plant diversity loss.

An ethnobotanical study of wild edible fruits in miombo woodlands of Tabora region in Western Tanzania

BackgroundWild edible fruits found in Tanzania's miombo woods are an indispensable source of food and medicine. Unfortunately, with the rapid expansion of human activities and urbanisation in the Tabora rural, Uyui and Sikonge districts of Western Tanzania, some wild fruits are disappearing due to the loss of plant diversity. The objectives of this study wereL: to document the knowledge related to wild edible fruits; to quantify the use and cultural significance, and to determine their threats.MethodsThe ethnobotanical study was conducted from June 2022 to February 2023 involving 244 local informants. The study used field visits, the collection of plant parts, and semi-structured interviews with locals for its data collection. Descriptive statistics and correlation test were used to analyse the knowledge related to wild fruits. Frequency citation (f) and use reports (UR) were computed to understand the diversity and cultural significance (CI).ResultsThe study documented 27 wild edible fruit species used for food and medicine. The life form constituted deciduous shrubs or trees (64%), shrub trees (21%) and evergreen or deciduous trees (15%). About (56%) of wild edible fruits were collected from June to August after the rainy season, (33%) were harvested between December and May during the rainy season, and (11%) were gathered from September and November before the rainy season. Household size and sex of the respondents were significantly correlated to the knowledge of wild edible fruits. Higher utilisation frequency (f) was recorded for Vitex mombassae Vatke (f = 0.84), Strychnos spinosa Lam. (f = 0.82), Vitex payos (Lour.) Merr. (f = 0.56), Phyllogeiton discolor (Klotzsch) Herzog. (f = 0.45), Vangueria infausta Burchell (f = 0.45), Tamarindus indica L. (f = 0.38), Parinari curatellifolia (f = 0.25), Landolphia parvifolia K.Schum. (f = 0.22) and Microcos conocarpa Burret (f = 0.22) fruits species. Additionally, Phyllogeiton discolor (Klotzsch) Herzog. (UR = 56), Vitex mombassae Vatke (UR = 56), Tamarindus indica L. (UR = 37), Strychnos spinosa Lam. (UR = 14) and Friesodielsia obovata (Benth.) Verdc. (UR = 11), have higher use reports (UR) and considered culturally important. Wild fruits were used to cure diabetes, gastrointestinal, reproductive, and respiratory infections ailments.Discussion and conclusionMultiple uses as well as the related knowledge of wild fruits have been documented. Friesodielsia obovata, Grewia flavescens Juss and Thespesia garckeana F.Hoffm. are the medicinal fruit species reported for the first time. Harvesting of wood plants, charcoal activities, crop cultivation, grazing expansion, and environmental change, have had an impact on the diversity of wild edible fruit plants. Over the past three decades, the use of wild fruits has been impacted by the loss of plant diversity due to decline of cultural norms on the forests management. Given the variety of uses for wild fruits, promoting markets for native fruits, sensitising the locals about the cultural importance and innovation on processing techniques are necessary to spur conservation efforts.

The loss of plant functional groups increased arthropod diversity in an alpine meadow on the Tibetan Plateau.

Plant species loss, driven by global changes and human activities, can have cascading effects on other trophic levels, such as arthropods, and alter the multitrophic structure of ecosystems. While the relationship between plant diversity and arthropod communities has been well-documented, few studies have explored the effects of species composition variation or plant functional groups. In this study, we conducted a long-term plant removal experiment to investigate the impact of plant functional group loss (specifically targeting tall grasses and sedges, as well as tall or short forbs) on arthropod diversity and their functional groups. Our findings revealed that the removal of plant functional groups resulted in increased arthropod richness, abundance and the exponential of Shannon entropy, contrary to the commonly observed positive correlation between plant diversity and consumer diversity. Furthermore, the removal of different plant groups had varying impacts on arthropod trophic levels. The removal of forbs had a more pronounced impact on herbivores compared to graminoids, but this impact did not consistently cascade to higher-trophic arthropods. Notably, the removal of short forbs had a more significant impact on predators, as evidenced by the increased richness, abundance, the exponential of Shannon entropy, inverse Simpson index and inverse Berger-Parker index of carnivores and abundance of omnivores, likely attributable to distinct underlying mechanisms. Our results highlight the importance of plant species identity in shaping arthropod communities in alpine grasslands. This study emphasizes the crucial role of high plant species diversity in controlling arthropods in natural grasslands, particularly in the context of plant diversity loss caused by global changes and human activities.

Plant Cryopreservation: Principles, Applications, and Challenges of Banking Plant Diversity at Ultralow Temperatures.

Progressive loss of plant diversity requires the protection of wild and agri-/horticultural species. For species whose seeds are extremely short-lived, or rarely or never produce seeds, or whose genetic makeup must be preserved, cryopreservation offers the only possibility for long-term conservation. At temperatures below freezing, most vegetative plant tissues suffer severe damage from ice crystal formation and require protection. In this review, we describe how increasing the concentration of cellular solutes by air drying or adding cryoprotectants, together with rapid cooling, results in a vitrified, highly viscous state in which cells can remain viable and be stored. On this basis, a range of dormant bud-freezing, slow-cooling, and (droplet-)vitrification protocols have been developed, but few are used to cryobank important agricultural/horticultural/timber and threatened species. To improve cryopreservation efficiency, the effects of cryoprotectants and molecular processes need to be understood and the costs for cryobanking reduced. However, overall, the long-term costs of cryopreservation are low, while the benefits are huge.

Appropriate livestock grazing alleviates the loss of plant diversity and maintains community resistance in alpine meadows

Alpine meadows constitute one of the major ecosystems on the Qinghai-Tibetan Plateau, with livestock grazing exerting a considerable impact on their biodiversity. However, the degree to which plant diversity influences community stability under different grazing intensities remains unclear in this region. This study conducted controlled grazing experiments across four levels of grazing intensity (no-, low-, medium-, and high-grazing) based on herbage utilization rate to assess the influence of grazing intensities on plant community structure and diversity-stability relationships. We discovered that high-grazing reduced plant diversity and attenuated the temporal stability and resistance of above-ground biomass. No- and low-grazing could alleviate plant biomass loss, with community resistance being optimal under low-grazing. The direct effects of livestock grazing on temporal stability were found to be negligible. Plant characteristics and diversity accounted for a substantial proportion of livestock grazing effects on community resistance (R2 = 0.46), as revealed by piecewise structural equation model analysis. The presence of plant diversity enhances the resistance of alpine meadows against disturbance and accelerates the recovery after grazing. Our results suggest that low-grazing intensity may represent a judicious option for preserving species diversity and community stability on the Qinghai-Tibetan Plateau.

Three decadal large‐scale ecological restoration projects across the Tibetan Plateau

AbstractAveraged over 4000 m in elevation, Tibetan Plateau (TP) functions as an important ecological security barrier in China. Alpine ecosystems present a trend of overall improvement under the influence of climate change and human activities, yet there are localized deteriorations. To improve the ecological function of the TP, large‐scale ecological restoration projects (ERPs) have been carried out over the past 30 years, which could be classified into three stages, that is, Exploration (1989–2003), Rapid Growth (2004–2014), and Comprehensive Development Stage (2015−present). With a total area of 850,000 km2, the ERPs include forest protection and construction, grassland protection and construction, water and soil erosion control, and desertification land management. The positive effect at the local scale has been widely verified, but the responses of productivity and species diversity were inconsistent. The positive effect at the regional scale gradually emerges, yet the spatial heterogeneity is significant, and the quantification of driving forces is an important prerequisite. There is a significant increase of rare wild animals in natural reserves, though it failed to curb the loss of animal and plant diversity in artificially planted areas. The long‐term effects of various ERPs on biodiversity should be taken into account so as to optimize the ecological measures and build a sustainable management model after project restoration. By summarizing the above achievements and problems of ERPs, we proposed a stepwise ecological restoration and adaptive management scheme by different restoration goals and reference modes, that is, “Environmental treatment—Ecological restoration projects—Adaptive management.”

Response of soil aggregate stability to plant diversity loss along an inundation stress gradient in a reservoir riparian zone

Dam-triggered periodic wetting and drying has increased the disintegration of soil particles in riparian areas. Most studies in this field have primarily explored the effects of vegetational characteristics on soil stability. However, the impact of plant diversity loss on the soil aggregate stability under periodic inundation stress remains unclear. This study investigated the relevant plant characteristics, root traits, and soil physicochemical properties in a typical riparian ecosystem along a hydrological stress gradient. Data-driven models were used to quantify the paths influencing soil aggregate stability through root traits under heterogeneous inundation stress. The findings showed that as inundation stress intensified, there was an overall decline in plant community diversity and soil aggregate stability in this riparian zone. Perennial herbs with fibrous root systems, as the dominant species, played an essential role in the subsurface soil aggregate stability under intense inundation stress, in contrast to the critical role of plant diversity under weak inundation stress. Moreover, the results revealed that root volume density and macroaggregate carbon content mediated the effects of plant diversity on riparian soil stability. Overall, the results suggest that suitable plants with high root volume density benefit essential soil aggregate stability under well-documented inundation effects in riparian zones.

Ex situ Conservation Efforts for Plant Diversity Protection with A Focus on Seeds

Plant diversity underpins ecological systems and provides materials that sustain humanity. Yet, plant diversity is being lost at a rate unparalleled in recent history, and the threat largely comes from anthropogenic pressures. As an effort to halt the continuing loss of global plant diversity, ex situ conservation has been gaining momentum. This article reviews the current ex situ conservation approaches with particular attention to botanic gardens, seed banks, cryopreservation, and seed vaults. Botanic gardens and conventional seed banks present their advantages and issues for effective plant conservation with cryopreservation complementing them in useful ways. Seed vaults that store seeds permanently occupy a unique place in plant conservation efforts. Of the two existing vaults, the Svalbard vault appears to have established itself as a global institution for the public good by safeguarding food and agriculture seed. The Korean vault, a relatively newer institution, may need further strategic efforts to build its clear identity and comparative niche, and distinguish itself as a global facility. While sustainably conserving plant diversity is an uphill challenge, increasing participation in ex situ conservation will certainly facilitate coping with the challenge.

ONTOGENETIC STRUCTURE OF POPULATION OF LAGOCHILUS PROSKORJAKOVII IKRAM IN UZBEKISTAN

Main of the global environmental problem is to conserve biodiversity in the world. Unfortunately, nowadays ineffective use plant resources by human and the loss of plant diversity. Anthropogenic factors influence is to increase Red List species in the nature. The basic aim of the case study was to estimate current populations of Lagochilus proskorjakovii Ikram. This analysis showed current of population of this species were mostly mature (g2).

Grassland degradation affects the response of soil bacterial and plant but not fungal diversity to nitrogen addition

Abstract Atmospheric nitrogen (N) deposition poses serious threats to plant and soil microbial communities in natural grasslands, which can have consequences on ecosystem functioning. However, the effects of atmospheric N deposition can be modulated by grassland degradation, defined here as soil erosion, soil nutrient decline and loss of plant diversity, which has become a global threat to the functioning of these ecosystems. It remains poorly understood whether the responses of plant and soil microbial communities to N deposition vary with grassland degradation. We conducted a 9‐year multilevel (0, 10, 20, 30, 40, 50 g N m−2 year−1) N enrichment experiment at four sites in Inner Mongolia, China. We evaluated grassland degradation using a compound index (grassland degradation index) and classified grassland sites into four categories: non‐degraded, moderately, severely and extremely degraded grasslands. One site was selected for each category, and then three replicates were set up within each site. N was added in the form of urea. We first observed that the response of soil bacterial diversity to N addition was stronger in degraded grasslands than in non‐degraded grasslands, whereas the response of soil fungal diversity was not affected by degradation. Meanwhile, N enrichment had a weaker impact on plant diversity in degraded grasslands compared to non‐degraded grasslands. The controlling factors that affected the responses of soil microbial diversity and community composition to N addition were inconsistent among grasslands with different degradation status. Soil pH was the main driver in non‐degraded grasslands, and plant community composition became an important driver in degraded grasslands. Synthesis. Our findings highlighted that grassland degradation affected the response of bacterial and plant communities to N deposition and provided new information for the management and conservation of biodiversity in degraded grasslands.