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The hemiparasitic tribe Cymbarieae (Orobanchaceae) plays a crucial role in elucidating the initial stage of the transition from autotrophism to heterotrophism. However, the complete chloroplast genome of the type genus Cymbaria has yet to be reported. In addition, the traditional Mongolian medicine Cymbaria daurica is frequently subjected to adulteration or substitution because of the minor morphological differences with Cymbaria mongolica. In this study, the complete chloroplast genomes of the two Cymbaria species were assembled and annotated, and those of other published 52 Orobanchaceae species were retrieved for comparative analyses. We found that the Cymbaria chloroplast genomes are characterized by pseudogenization or loss of stress‐relevant genes (ndh) and a unique rbcL–matK inversion. Unlike the high variability observed in holoparasites, Cymbaria and other hemiparasites exhibit high similarity to autotrophs in genome size, guanine–cytosine (GC) content, and intact genes. Notably, four pairs of specific DNA barcodes were developed and validated to distinguish the medicinal herb from its adulterants. Phylogenetic analyses revealed that the genus Cymbaria and the Schwalbea–Siphonostegia clade are grouped into the tribe Cymbarieae, which forms a sister clade to the remaining Orobanchaceae parasitic lineages. Moreover, the diversification of monophyletic Cymbaria occurred during the late Miocene (6.72 Mya) in the Mongol–Chinese steppe region. Our findings provide valuable genetic resources for studying the phylogeny of Orobanchaceae and plant parasitism, and genetic tools to validate the authenticity of the traditional Mongolian medicine "Xinba." [ABSTRACT FROM AUTHOR]

Background: The coronavirus disease 2019 (COVID-19) outbreak has increased the work pressure of nurses worldwide, and managers must provide support and assistance for the transition period of newly graduated nurses. Method: A cross-sectional design was adopted to collect a sample of 318 newly graduated nurses from six hospitals in China during the COVID-19 pandemic. Data were collected using a questionnaire that consisted of a demographic questionnaire, the Transition Shock Scale (2015), the Career Adapt-Ability Scale (2012), and the General Self-Efficacy Scale (2001). Results: The transition shock of newly graduated nurses was 3.77 ± 0.48 in China. Regression analysis showed that transition shock among newly graduated nurses was predicted by career adaptability, general self-efficacy, living with one's parents, and education level, which accounted for 37.7% of the variance in transition shock. Conclusion: Newly graduated nurses experienced a relatively high level of transition shock in China during the COVID-19 pandemic. Managers may offer continuing education to reduce the transition shock of newly graduated nurses based on the factors that affect their transition shock. [J Contin Educ Nurs. 2023;54(11):524–532.] [ABSTRACT FROM AUTHOR]

Soil legacy effects and biodiversity play important roles in driving plant community dynamics and functioning. However, experimental evidence of the effects of soil legacy on ecosystem multifunctionality (maintaining multiple functions simultaneously) is lacking. We first conducted a mesocosm experiment in which three common species (grass, legume, and forb) were planted in monocultures and mixed cultures to produce soil legacies. Subsequently, soils were sampled to test the soil legacy effects on ecosystem multifunctionality in a greenhouse experiment. Our findings showed that plant‐mediated soil legacy effects were species‐specific and strongly influenced the productivity of subsequent plants or combinations. Specifically, plant‐specific soil legacies had considerable impacts on the magnitude and direction of diversity‐dependent overyielding effects. Such effects can compensate for non‐legume soil legacy effects and maintain overall productivity. Functional diversity and ecosystem multifunctionality were largely affected by soil legacy effects and were significantly positively correlated with functional group richness. Based on our results, plant‐specific soil legacy is an important factor limiting the development of plant community and ecosystem multifunctionality in the early stage of community construction. The rational use of the synergistic effects of plant‐specific soil legacy and functional group richness may be a key to ensure the successful establishment of vegetation and grassland management. [ABSTRACT FROM AUTHOR]

Herders' livelihood strategies are functions of the capitals at their disposal. Although this thesis has been proved, it has not been applied to livelihood research in the context of conservation initiatives. The Chinese government implemented the Grassland Ecological Compensation Policy (GECP) in 2011. However, the impact of the policy on herders' livelihoods is still unclear. This study measured the variation in herders' livelihood strategies in the desert grassland of Inner Mongolia, China, after the implementation of the GECP. This study also analyzed the impacts of livelihood capitals on the livelihood strategies, revealing the shortages of different livelihood strategies. The results showed the following: After the GECP, (1) herders' livelihood strategies could be grouped into five types based on livelihood capitals. The livelihood capitals of herders varied greatly, resulting in large economical gaps among households with different livelihood strategies. (2) The herders' livelihood strategies were affected by factors including the education, age, social communication, amount of livestock, income, and subsidy of the herders. (3) The main income sources of different livelihood strategies were both subsidy and livestock husbandry. In general, the GECP drives the differentiation of herders' livelihoods remarkably. Future conservation initiatives should take the shortages of different livelihood strategies into account. [ABSTRACT FROM AUTHOR]

Desertification is a worldwide problem caused by climate change and human activity in dryland regions. In China, approximately 27% of the land surface is desertified. In these desertified ecosystems, aboveground interactions are known to greatly affect ecological succession, but belowground soil microbial communities are relatively unstudied. It is not yet clear how these communities change with different vegetation patch types (e.g., shrub vs. grass) across successional stages in dryland ecosystems. In this study, we assessed the effects of shrub patches (dominated by Artemisia ordosica) and grass patches on soil microbial community diversity, soil environment, and soil substrates across three successional stages (mobile, semi‐mobile, and fixed dunes) in a sand dune ecosystem in the Kubuqi Desert, China. Microbial alpha diversity, as indicated by the Shannon index or operational taxonomic unit (OTU) richness, was not affected by patch type but increased with successional stages. Patch type‐ or successional stage‐induced changes in soil bacterial and fungal alpha diversity were mainly associated with soil organic carbon. Unlike alpha diversity, soil microbial beta diversity was greatly affected by successional stage and patch type. The Mantel test revealed that changes in soil bacterial beta diversity were mainly associated with soil organic carbon, and changes in soil fungal beta diversity were mainly associated with soil organic carbon and soil pH. Microbial OTU richness responded more strongly to the successional stage than the microbial Shannon index, indicating that microbial OTU richness can be used as an indicator of successional status in desert ecosystems. The consistent differences in microbial beta diversity between shrub and grass patches across the three successional stages indicate that shrubs significantly influence soil microbial communities in desert ecosystems. [ABSTRACT FROM AUTHOR]

Understanding the driving factors of soil multifunctionality is of great significance for the protection and restoration of degraded terrestrial ecosystems. However, the effects of above‐ and belowground factors are rarely evaluated simultaneously, and the driving mode of both factors on soil multifunctionality is not clear. Here, we evaluated the restoration of mobile dunes threatened by desertification through aerial seeding, that is, the sowing of seeds through aerial devices, from 1983 to 2015 in Mu Us Desert, China, using soil and plant data. The effect of aerial seeding on the restoration of soil multifunctionality, plant diversity, and soil microbial diversity in mobile dunes was significant, which was tested by loess regression. Further, the plant diversity becomes saturated in the later stages of restoration. The effect also leads to the restoration of soil multifunctionality lags behind plant and soil microorganisms. The factors (plant and soil microorganisms) driving soil multifunctionality is not a separate action or a joint action that test by structural equation models (SEMs), but that plants restore first and then indirectly drive soil multifunctionality through soil microorganisms during the restoration process. We also found that bacteria are the main direct indicators of soil multifunctionality, which was tested using Random forests modelling. This study highlights that plants indirectly drive soil multifunctionality through soil microorganisms, and soil microorganisms are key to elucidating the restoration mechanism and process. [ABSTRACT FROM AUTHOR]

Grassland is one of the most widely-distributed ecosystems on Earth and provides a variety of ecosystem services. Grasslands, however, currently suffer from severe degradation induced by human activities, overgrazing pressure and climate change. In the present study, we explored the transcriptome response of Stipa breviflora, a dominant species in the desert steppe, to grazing through transcriptome sequencing, the development of simple sequence repeat (SSR) markers, and analysis of genetic diversity. De novo assembly produced 111,018 unigenes, of which 88,164 (79.41%) unigenes were annotated. A total of 686 unigenes showed significantly different expression under grazing, including 304 and 382 that were upregulated and downregulated, respectively. These differentially expressed genes (DEGs) were significantly enriched in the "alpha-linolenic acid metabolism" and "plant-pathogen interaction" pathways. Based on transcriptome sequencing data, we developed eight SSR molecular markers and investigated the genetic diversity of S. breviflora in grazed and ungrazed sites. We found that a relatively high level of S. breviflora genetic diversity occurred under grazing. The findings of genes that improve resistance to grazing are helpful for the restoration, conservation, and management of desert steppe. [ABSTRACT FROM AUTHOR]

Context: Understanding the ecology and sustainability of the Inner Mongolian Grassland is crucial for improving land management policies in the Mongolian Plateau and beyond. However, a systematic and comprehensive review of the relevant literature is still lacking. Objectives: This review was intended to: (1) assess the current state of the ecological and sustainability research of the Inner Mongolian Grassland region, and (2) identify critical research topics and challenges for understanding pathways to sustainability of the region. Methods: We conducted a bibliometric analysis of 2571 English articles indexed in the Web of Science during 1998–2019. Multiple methods, including descriptive statistics, principal component analysis, change point detection, theme mining, and association strength analysis, were combined to analyze the sampled literature. Results: All reviewed studies can be grouped into four types: description of ecological and biogeochemical characteristics of degraded grasslands (type I), the impacts of climate change and human activities on aboveground (type II) and belowground grassland ecosystem functioning (type III), and the impacts of different management strategies on grassland ecosystem services and human well-being (type IV). The number of publications in all four themes has rapidly increased after 2007–2009. The four types of articles were related to each other in terms of the interannual publication consistency. Keyword co-occurrence network analysis showed that climate change and grazing were the major research topics, which are closely related to all other topics. Conclusions: Three perspectives have persisted in the ecology and sustainability research of the Inner Mongolian Grassland: Ecology in the Grassland, Ecology of the Grassland, and Sustainability of the Grassland. Based on the emerging landscape sustainability science framework, the transdisciplinary approach to landscape sustainability diagnostics and landscape planning and design should become a priority in advancing sustainability research of the region. [ABSTRACT FROM AUTHOR]

Silicon (Si) has been known to enhance salt resistance in plants. In this experiment, 4-weeks-old alfalfa seedlings were exposed to different NaCl concentrations (0–200 mM) with or without 2 mM Si for two weeks. The results showed that NaCl-stressed alfalfa seedlings showed a decrease in growth performance, such as stem extension rate, predawn leaf water potential (LWP) and the chlorophyll content, potassium (K+) concentration, as well as the ratio of potassium/sodium ion (K+/Na+). In contrast, NaCl-stressed alfalfa seedlings increased leaf Na+ concentration and the malondialdehyde (MDA) level, as well as the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) in alfalfa leaves. Besides, exogenous Si application enhanced photosynthetic parameters of NaCl-stressed alfalfa seedlings, which was accompanied by the improvement in predawn LWP, level of chlorophyll content, and water use efficiency (WUE). The Si-treated plants enhanced salinity tolerance by limiting Na+ accumulation while maintaining K+ concentration in leaves. It also established K+/Na+ homeostasis by increasing K+/Na+ radio to protect the leaves from Na+ toxicity and thereby maintained higher chlorophyll retention. Simultaneously, Si-treated plants showed higher antioxidant activities and decreased MDA content under NaCl stress. Our study concluded that Si application enhanced salt tolerance of alfalfa through improving the leaves photosynthesis, enhancing antioxidant performance and maintaining K+/Na+ homeostasis in leaves. Our data further indicated exogenous Si application could be effectively manipulated for improving salt resistance of alfalfa grown in saline soil. [ABSTRACT FROM AUTHOR]

Degradation of semi-arid and arid ecosystems due to desertification is arguably one of the main obstacles for sustainability in those regions. In recent decades, the Mu Us Desert in China has experienced such ecological degradation making quantification of spatial patterns of desertification in this area an important research topic. We analyzed desertification dynamics for seven periods from 1986 to 2015 and focused on five ecosystem services including soil conservation, water retention, net primary productivity (NPP), crop productivity, and livestock productivity, all assessed for 2015. Furthermore, we examined how ecosystem services relate to each other and are impacted by desertification. Three major conclusions are drawn from the study. First, the eastern part of the study area experienced overall improvement while desertification in the west first increased and then reversed its trend during those periods between 1986 and 2015. Second, significant synergistic relationships are observed for three regulating services (soil conservation, water retention, NPP) and two provisioning services (crop productivity and livestock productivity). Strong relationships across different types of ecosystem services were found only between crop productivity and NPP. Third, in response to increasing desertification, the three regulating services exhibit a monotonically decreasing trend, while the two provisioning services follow a hump-shaped response. [ABSTRACT FROM AUTHOR]

The relationship between biodiversity and productivity has been a hot topic in ecology. However, the relative importance of taxonomic diversity and functional characteristics (including functional dominance and functional diversity) in maintaining community productivity and the underlying mechanisms (including selection and complementarity effects) of the relationship between diversity and community productivity have been widely controversial. In this study, 194 sites were surveyed in five grassland types along a precipitation gradient in the Inner Mongolia grassland of China. The relationships between taxonomic diversity (species richness and the Shannon-Weaver index), functional dominance (the community-weighted mean of four plant traits), functional diversity (Rao's quadratic entropy), and community aboveground biomass were analyzed. The results showed that (1) taxonomic diversity, functional dominance, functional diversity, and community aboveground biomass all increased from low to high precipitation grassland types; (2) there were significant positive linear relationships between taxonomic diversity, functional dominance, functional diversity, and community aboveground biomass; (3) the effect of functional characteristics on community aboveground biomass is greater than that of taxonomic diversity; and (4) community aboveground biomass depends on the community-weighted mean plant height, which explained 57.1% of the variation in the community aboveground biomass. Our results suggested that functional dominance rather than taxonomic diversity and functional diversity mainly determines community productivity and that the selection effect plays a dominant role in maintaining the relationship between biodiversity and community productivity in the Inner Mongolia grassland. [ABSTRACT FROM AUTHOR]

Climate change has significant effects on primary productivity and ecosystem function. To assess these effects in the Inner Mongolia Plateau of China, we analysed the 8 km normalized difference vegetation index (NDVI) time-series from the Global Inventory Monitoring and Modeling System (GIMMS) data set and characterized vegetation productivity between 1981 and 2011. We used canonical correspondence analysis (CCA) to elucidate the relationship between productivity and climatic factors for different vegetation types and model the response of productivity to climate change. We found the following. (1) Productivity in the study area exhibits high spatial heterogeneity while generally decreasing from northeast to southwest, which is mainly driven by precipitation patterns. (2) Most of the total variation (88.35%) of NDVI can be explained by precipitation and temperature. Around 46.19% of the total variation is explained solely by precipitation, 31.85% by temperature, and 10.31% by the precipitation and temperature interaction term. (3) Productivity of most ecosystems of the area increased gradually between 1981 and 2011. The central region of the Plateau is characterized by the high annual coefficient of variation (CV) of NDVI, which is mainly attributable to the desert steppe, the most sensitive ecosystem of the area. (4) Climate factors influence primary productivity differently in different vegetation zones of our study area. Primary productivity of forest and agricultural areas is explained mainly by temperature and steppe vegetation by precipitation. Desert vegetation is closely related to both precipitation and temperature. Not only did the study quantitatively assess the effects of climate changes on primary production, but it also provided an important basis for a comprehensive analysis of climate change on ecosystem function in the Inner Mongolia Plateau. [ABSTRACT FROM PUBLISHER]

Background: The redundancy hypothesis predicts that the species redundancy in a plant community enhances community stability. However, numerous studies in recent years questioned the positive correlation between redundancy and stability. Methodology: We explored the relationship between the species redundancy, functional redundancy and community stability in typical steppe grassland in Northern China by sampling grassland vegetation along a gradient of resource availability caused by micro-topography. We aimed to test whether community redundancy enhanced community stability, and to quantify the relative importance of species redundancy and functional redundancy in maintaining community stability. Results: Our results showed that the spatial stability of plant community production increases with increased supply of soil resources, and the functional redundancy instead of species diversity or species redundancy is correlated with the community stability. Our results supported the redundancy hypothesis and have implications for sustainable grassland management. [ABSTRACT FROM AUTHOR]

Understanding the distribution pattern and maintenance mechanism of species diversity along environmental gradients is essential for developing biodiversity conservation strategies under environmental change. We have surveyed the species diversity at 192 vegetation sites across different steppe zones in Inner Mongolia, China. We analysed the total species diversity (γ diversity) and its composition (α diversity and β diversity) of different steppe types, and their changes along a precipitation gradient. Our results showed that (i) β diversity contributed more than α diversity to the total (γ) diversity in the Inner Mongolia grassland; the contribution of β diversity increased with precipitation, thus the species-rich (meadow steppe) grassland had greater contribution of β diversity than species-poor (desert steppe) grassland. (ii) All α, β and γ species diversity increased significantly (P<0.05) with precipitation, but their sensitivity to precipitation (diversity change per mm precipitation increase) was different between the steppe types. The sensitivity of α diversity of different steppe community types was negatively (P<0.05) correlated with mean annual precipitation, whereas the sensitivity of β and γ diversity showed no trend along the precipitation gradient (P>0.10). (iii) The α diversity increased logarithmically, while β diversity increased exponentially, with γ diversity. Our results suggest that for local species diversity patterns, the site species pool is more important in lower precipitation areas, while local ecological processes are more important in high precipitation areas. In addition, for β diversity maintenance niche processes and diffusion processes are more important in low and high precipitation areas, respectively. Our results imply that a policy of “multiple small reserves” is better than one of a “single large reserve” for conserving species diversity of a steppe ecosystem, and indicate an urgent need to develop management strategies for climate-sensitive desert steppe ecosystem. [ABSTRACT FROM AUTHOR]

Productivity-species diversity relationships have been a controversial research topic in ecology with scale believed to be among the main reasons for discovering different relationships. We collected data on species diversity (richness) and productivity (peak above-ground biomass) of the Stipa breviflora association in the Inner Mongolia grassland to examine spatial scale dependency and possible underlying mechanisms responsible for the relationships found. One local and seven different landscape scales (the first level corresponds in extent to a 100 × 100 km area, which is increased consecutively by 100 km resulting in the 700 × 700 km area at the highest level) were considered. We found that: (1) unimodal relationships dominated the local scale, but this varied depending on the position along successional gradients; (2) a positive linear relationship was common at larger spatial scales; (3) biotic processes were the most likely primary factor underlying local scale unimodal relationships, but environmental heterogeneity (precipitation patterns) was the main determinant of relationships found at larger spatial scales; (4) our study contributed to other empirical evidence and predictions of theoretical models regarding scale dependency of productivity-species richness relationships; (5) while earlier research demonstrated positive linear species richness-productivity relationships across a number of ecological scales in the Inner Mongolia steppe, our study specifically tested a spectrum of geographical scales to confirm the scale-dependency of this relationship. Lastly, our study emphasized the critical role played by precipitation patterns in controlling biodiversity and grassland ecosystem functioning, which maintains the relatively high level of biodiversity and stable ecosystem processes. [ABSTRACT FROM AUTHOR]

The accumulation of heat and moderate precipitation are the primary factors that are used by grasslands to trigger a green-up date. The accumulated growing degree-days (AGDD) requirement over the preseason is an important indicator of the response of grassland spring phenology to climate change. This study adopted the Normalized Difference Phenology Index (NDPI), which derived from the Moderate Resolution Imaging Spectroradiometer (MODIS), to extract annual green-up dates in the Hulun Buir grassland in China between 2001–2015. Our analysis indicated that the range (standard deviation) and trend for the green-up date were DOY (day of year) 104 to DOY 144 (10.6 days) and −2.0 days per decade. Nine point two percent of the study area had significant (p < 0.05) changes in AGDD requirements. The partial correlations between the AGDD requirements and chilling days (67.04%, pixels proportion) were negative and significant (p < 0.05). The partial correlations between the AGDD requirement and precipitation (28.87%) were positive and significant (p < 0.05). Finally, the partial correlation between the AGDD requirement and insolation (97.65%) were positive and significant (p < 0.05). The results of this study could reveal the response of vegetation to climate warming and contribute to improving the phenological mechanism model of different grassland types in future research. [ABSTRACT FROM AUTHOR]

Crop reduction caused by cryogenesis and drought is a serious and global problem. The environmental stress caused by low temperature and drought during the overwintering stage of forage is the key factor leading to this low yield. In cold and arid grassland, winter irrigation can effectively alleviate the stress of alfalfa during overwintering, improve the survival rate of alfalfa, and significantly increase the yield. However, the water uptake patterns of alfalfa under winter irrigation are not clear, which are important to explore the mechanism of alleviating environmental stress by winter irrigation. In this research, the stable isotope compositions of all probable water sources and alfalfa xylem water were measured after winter irrigation. A graphical method was applied to identify the main soil layers with water uptake by the alfalfa roots. The contribution rate of available water sources to alfalfa xylem water was quantified by the MixSIAR (Bayesian isotope analysis mixing model in R) model. The results indicated that alfalfa absorbed soil water when the soil water content was high enough in the root layer when under high water volume freezing irrigation (irrigation in early winter when soil is freezing) but not under low and medium water volume freezing irrigation. Alfalfa gradually began to absorb soil water on the third day after thawing irrigation (irrigation in late winter when the soil is thawing) and showed different water uptake characteristics under low, medium, and high water volume. Thawing irrigation also accelerated the regeneration of alfalfa. [ABSTRACT FROM AUTHOR]

The traditional livestock industry in Inner Mongolia has evolved rapidly in response to social and economic transformations during recent decades, resulting in substantial impacts on the rural economy and livelihoods of pastoralists. Improved understanding of these changes and potential drivers may help foster strategies to sustain the pastoral system of this region. Using long-term climate, social-economic, and livestock (cattle, horses, sheep, and goats) population data from 1970 to 2010, we analyzed the dynamics of the livestock industry and main driving factors in the Xilinhot region—a central part of the Inner Mongolia Grassland. Our results show that the total livestock population increased dramatically in the past four decades, especially during 1987–2010. Livestock composition also changed substantially, with increasing sheep, goat, and cattle populations but a decreasing horse population. Pastoral population growth and land use policy were the primary drivers for livestock dynamics during 1970–2010. Livestock structure became differentiated progressively with changes in land use policy. Also, climate factors had an important influence on livestock production. The current study suggests that sustainable animal husbandry in this region requires government policies that promote ecological urbanization, livestock production efficiency, incentive systems for grassland conservation, and collective action and cooperation for enhancing social capital and resilience. [ABSTRACT FROM AUTHOR]