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1.
J Environ Manage ; 355: 120365, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38460328

RESUMO

Land use/land cover (LULC) change and climate change are interconnected factors that affect the ecological environment. However, there is a lack of quantification of the impacts of LULC change and climate change on landscape ecological risk under different shared socioeconomic pathways and representative concentration pathways (SSP-RCP) on the Mongolian Plateau (MP). To fill this knowledge gap and understand the current and future challenges facing the MP's land ecological system, we conducted an evaluation and prediction of the effects of LULC change and climate change on landscape ecological risk using the landscape loss index model and random forest method, considering eight SSP-RCP coupling scenarios. Firstly, we selected MCD12Q1 as the optimal LULC product for studying landscape changes on the MP, comparing it with four other LULC products. We analyzed the diverging patterns of LULC change over the past two decades and observed significant differences between Mongolia and Inner Mongolia. The latter experienced more intense and extensive LULC change during this period, despite similar climate changes. Secondly, we assessed changes in landscape ecological risk and identified the main drivers of these changes over the past two decades using a landscape index model and random forest method. The highest-risk zone has gradually expanded, with a 30% increase compared to 2001. Lastly, we investigated different characteristics of LULC change under different scenarios by examining future LULC products simulated by the FLUS model. We also simulated the dynamics of landscape ecological risks under these scenarios and proposed an adaptive development strategy to promote sustainable development in the MP. In terms of the impact of climate change on landscape ecological risk, we found that under the same SSP scenario, increasing RCP emission concentrations significantly increased the areas with high landscape ecological risk while decreasing areas with low risk. By integrating quantitative assessments and scenario-based modeling, our study provides valuable insights for informing sustainable land management and policy decisions in the region.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Conservação dos Recursos Naturais/métodos , Ecossistema , Desenvolvimento Sustentável , Previsões
2.
J Contin Educ Nurs ; 54(11): 524-532, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37747141

RESUMO

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.].


Assuntos
COVID-19 , Enfermeiras e Enfermeiros , Humanos , Autoeficácia , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Inquéritos e Questionários , China/epidemiologia
3.
Front Plant Sci ; 14: 1170075, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37265641

RESUMO

Investigating the genetic mechanisms of local adaptation is critical to understanding how species adapt to heterogeneous environments. In the present study, we analyzed restriction site-associated DNA sequencing (RADseq) data in order to explore genetic diversity, genetic structure, genetic differentiation, and local adaptation of Stipa breviflora. In total, 135 individual plants were sequenced and 25,786 polymorphic loci were obtained. We found low genetic diversity (He = 0.1284) within populations of S. breviflora. Four genetic clusters were identified along its distribution range. The Mantel test, partial Mantel test, and multiple matrix regression with randomization (MMRR) indicate that population differentiation was caused by both geographic distance and environmental factors. Through the FST outlier test and environmental association analysis (EAA), 113 candidate loci were identified as putatively adaptive loci. RPK2 and CPRF1, which are associated with meristem maintenance and light responsiveness, respectively, were annotated. To explore the effects of climatic factors on genetic differentiation and local adaptation of S. breviflora, gradient forest (GF) analysis was applied to 25,786 single nucleotide polymorphisms (SNPs) and 113 candidate loci, respectively. The results showed that both temperature and precipitation affected the genetic differentiation of S. breviflora, and precipitation was strongly related to local adaptation. Our study provides a theoretical basis for understanding the local adaptation of S. breviflora.

4.
PLoS One ; 15(12): e0244222, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33351838

RESUMO

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.


Assuntos
Pradaria , Poaceae/genética , Polimorfismo Genético , Transcriptoma , Animais , Biodiversidade , Bovinos/fisiologia , Genoma de Planta , Herbivoria , Repetições de Microssatélites , Poaceae/fisiologia
5.
Front Plant Sci ; 11: 1183, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32983188

RESUMO

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.

6.
Sci Total Environ ; 726: 138529, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32305761

RESUMO

Previous studies have demonstrated that plant diversity not only plays an important role in maintaining ecosystem functions but can also mediate the impact of climate change on ecosystem functions. However, the relative importance of multiple aspects of diversity at different scales remains unclear. In this study, we investigated species, functional, and phylogenetic aspects of diversity at α and ß scales, and measured eight soil functions (aboveground productivity, soil organic carbon, total soil nitrogen, total soil phosphorus, soil available nitrogen, soil available phosphorus, soil carbon-nitrogen ratio, and soil nitrogen-phosphorus ratio) to comprehensively assess the relationship between multiple aspects and scales of plant diversity and soil multifunctionality along an aridity gradient across the grasslands of Inner Mongolia. Diversity at α and ß scales explained soil multifunctionality synergistically. Functional diversity explained most of the soil multifunctionality, while phylogenetic diversity explained the least. Aridity had both direct effects on soil multifunctionality, and indirect effects mediated mainly by functional α and ß diversity. These findings indicate that in addition to α diversity, ß diversity also played an important role in maintaining soil multifunctionality, and was an important mediator for the adverse impact of aridity on soil multifunctionality. Our study highlights the critical role of ß diversity, especially regarding functional traits, in predicting the consequences of the increasingly arid conditions in the Inner Mongolian grasslands.


Assuntos
Ecossistema , Solo , Biodiversidade , Carbono , China , Filogenia
7.
Foods ; 8(11)2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31694278

RESUMO

The aim of this study was to develop and validate an improved, simple, and sensitive method for the simultaneous determination of seven types (cadaverine, CAD; hexylamine, HEX; histamine, HIS; phenylethylamine, PEA; putrescine, PUT; tyramine, TYR) of biogenic amines (BAs) in wine matrices. For this reason, a modified QuEChERS combined with ultra-performance liquid chromatography coupled to a triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS) method was investigated. The optimization of UHPLC-QqQ-MS/MS separation and QuEChERS procedure was performed. Under optimum conditions, the excellent chromatographic performance of the whole separation was accomplished within 6.3 min analyzing time. Meanwhile, the recoveries ranged from 77.2% to 101.7%, while relative standard deviation (RSD) remained between 0.0% and 9.4%. The limit of detection (LOD, 0.50-1.00 µg/L) and the limit of quantification (LOQ, 1.65-3.30 µg/L) were lower than those permitted by legislation in food matrices, which demonstrated the high sensitivity and applicability of this efficient method. This validated method was also applied in a pilot study to analyze BAs in 81 wine samples from Hexi Corridor Region (Gansu Province, Northwest China), CAD, HEX, HIS, PEA, PUT, and TYR were detected to varying degrees in the samples. However, when compared with the existing standards, the BAs in all 81 wine samples did not exceed the prescribed limit value or toxic dose (2-40 mg/L). Moreover, a statistical approach was also conducted using Pearson correlation analysis, and to evaluate their concentrations in terms of wine parameters (storage time, grape variety, wine type, and basic physicochemical index). The results showed that, among the seven kinds of BAs, the concentration of HIS had a certain correlation with alcoholic degree and grape variety. In addition, the level of PEA had a certain correlation with the wine pH and wine storage time. It is worth noting that this seems to be the first report regarding the application of QuEChERS-UHPLC-QqQ-MS/MS in the analysis of BAs in wine in this region.

8.
Nature ; 559(7713): 193-204, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29995865

RESUMO

China has responded to a national land-system sustainability emergency via an integrated portfolio of large-scale programmes. Here we review 16 sustainability programmes, which invested US$378.5 billion (in 2015 US$), covered 623.9 million hectares of land and involved over 500 million people, mostly since 1998. We find overwhelmingly that the interventions improved the sustainability of China's rural land systems, but the impacts are nuanced and adverse outcomes have occurred. We identify some key characteristics of programme success, potential risks to their durability, and future research needs. We suggest directions for China and other nations as they progress towards the Sustainable Development Goals of the United Nations' Agenda 2030.


Assuntos
Solo , Desenvolvimento Sustentável/tendências , Agricultura , Biodiversidade , China , Conservação dos Recursos Naturais , Abastecimento de Alimentos , Florestas , Objetivos , Pradaria , Desenvolvimento Sustentável/economia , Desenvolvimento Sustentável/legislação & jurisprudência , Fatores de Tempo , Nações Unidas , Água
9.
Sci Total Environ ; 644: 806-814, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-29990929

RESUMO

Intensive anthropogenic land-use causes habitat loss and landscape homogenization, which leads to the decrease of biodiversity and ecosystem degradation. Therefore, it is important to study the influence of landscape heterogeneity on biodiversity. In this study, vegetation surveys conducted at 53 sites in the Tabu River basin, located at the agro-pastoral ecotone of Inner Mongolia of China, revealed 146 species. Species diversity was evaluated at three scales: species richness within patches (alpha diversity), between patches (beta diversity) and at the landscape scale (gamma diversity). We analyzed landscape heterogeneity (LHtotal) and its driving factors including environmental variables (LHDFenv-var, such as precipitation and altitude), environmental heterogeneity (LHDFenv-het) and human activities (LHDFhum). We used structural equation modeling (SEM) to evaluate the response of species richness to landscape heterogeneity at three scales and determined the relative contribution of driving factors in explaining species diversity at these scales. The results of the study are summarized as follows: 1) Alpha diversity was the dominant component of gamma diversity in the Tabu River basin in Inner Mongolia. 2) There is no significant correlation (P = 0.512) between alpha diversity and LHtotal; with the increase of LHtotal beta and gamma diversities showed hump-shaped relationships. 3) LHDFenv-het was the primary factor in maintaining alpha diversity, with heterogeneity of mean annual precipitation (MAP), temperature (MAT) and altitude (ALT) acting as three largest contributors. LHDFhum primarily contributed to the maintenance of beta diversity. 4) LHDFhum was the primary contributor to gamma diversity, and human activity exceeded threshold values for positive effects. Based on our findings we suggest liming agricultural use along the river to prevent reductions in species diversity.


Assuntos
Biodiversidade , Ecossistema , Plantas/classificação , Agricultura , China , Monitoramento Ambiental
10.
Appl Plant Sci ; 5(4)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28439477

RESUMO

PREMISE OF THE STUDY: Stipa breviflora (Poaceae) is one of the dominant species of the desert steppe in the eastern Eurasian grasslands. Simple sequence repeat (SSR) markers were developed for use in genetic diversity studies of this species. METHODS AND RESULTS: A total of 1954 potentially polymorphic loci were obtained by comparing transcriptome data of eight different S. breviflora individuals. We selected 81 loci to verify polymorphism and 63 loci amplified, of which 21 loci exhibited polymorphism. The number of alleles per locus varied from two to 24, the observed heterozygosity ranged from 0.083 to 0.958, and the expected heterozygosity ranged from 0.396 to 0.738. CONCLUSIONS: These newly identified SSR loci can be used for population genetic and landscape genetic studies of S. breviflora. In addition, 14 loci also amplified in six related Stipa species (S. grandis, S. krylovii, S. bungeana, S. aliena, S. gobica, and S. purpurea).

11.
Ecol Evol ; 7(5): 1605-1615, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28261469

RESUMO

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.

12.
PLoS One ; 10(12): e0145605, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26699133

RESUMO

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.


Assuntos
Biodiversidade , Ecossistema , Fenômenos Fisiológicos Vegetais , Plantas/classificação , China , Conservação dos Recursos Naturais , Especificidade da Espécie
13.
Ying Yong Sheng Tai Xue Bao ; 25(1): 1-11, 2014 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-24765835

RESUMO

Sustainability is the theme of our time and also the grandest challenge to humanity. Since the 1970s, the term, sustainable development, has frequently appeared in the scientific literature, governmental documents, media promotions for public goods, and commercial advertisements. However, the science that provides the theoretical foundation and practical guidance for sustainable development--sustainability science--only began to emerge in the beginning of the 21st century. Nevertheless, the field has rapidly developed in depth and expanded in scope during the past decade, with its core concepts and research methods coalescing. China, as the most populous country in the world and home to the philosophical root of sustainability science-the unity of man and nature, is obligated to take upon the challenge of our time, to facilitate global sustainability while pursuing the Chinese Dream, and to play a leading role in the development of sustainability science. Toward this grandiose goal, this paper presents the first Chinese introduction to sustainability science, which discusses its basic concepts, research questions, and future directions. Sustainability science is the study of the dynamic relationship between humans and the environment, particularly focusing on the vulnerability, robustness, resilience, and stability of the coupled human-environment system. It is a transdisciplinary science that integrates natural sciences with humanities and social sciences. It hinges on the environment-economy-society nexus, and merges basic and applied research. The key components of sustainability often change with time, place, and culture, and thus sustainability science needs to emphasize multi-scale studies in space and time, with emphasis on landscapes and regions over a horizon of 50 to 100 years. It needs to focus on the relationship between ecosystem services and human well-being, as influenced by biodiversity and ecosystem processes as well as climate change, land use change, and other socioeconomic drivers. Landscape sustainability is at the core of sustainability science, and is expected to be a hot research topic in the next few decades.


Assuntos
Conservação dos Recursos Naturais , China , Mudança Climática , Ecossistema , Meio Ambiente , Humanos
14.
PLoS One ; 9(3): e93518, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24675900

RESUMO

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 ß diversity) of different steppe types, and their changes along a precipitation gradient. Our results showed that (i) ß diversity contributed more than α diversity to the total (γ) diversity in the Inner Mongolia grassland; the contribution of ß diversity increased with precipitation, thus the species-rich (meadow steppe) grassland had greater contribution of ß diversity than species-poor (desert steppe) grassland. (ii) All α, ß 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 ß and γ diversity showed no trend along the precipitation gradient (P>0.10). (iii) The α diversity increased logarithmically, while ß 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 ß 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.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Pradaria , Modelos Estatísticos , Poaceae/fisiologia , China , Clima Desértico , Chuva , Solo/química
15.
Ying Yong Sheng Tai Xue Bao ; 19(9): 2009-15, 2008 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19102317

RESUMO

Based on the RS image of Longitudinal Range-Gorge Region (LRGR) in 2001, the study area was classified into seven first-class landscape types (forestland, grassland, farmland, wetland, water body, urban land, and glacier), and 26 second-class landscape types in consideration of climate belt, vegetation, and topography. By using GIS technology, the services value of different landscape types of LRGR were studied in regards to the study results on services value of Chinese terrestrial ecosystems. The results indicated that the total services value of LRGR was 5 302.35 x 10(8) yuan x a(-1), accounting for 9.47% of the whole country. The service value of soil conservation was the highest, which occupied 18.05% of the total services value, while the service values of gas adjustability and biodiversity protection ranked the second and third. Due to its distribution extent and services intensity per unit area, the forest landscape, which covered 66.11% of the total area, contributed most (85.34%) to the total service value of LRGR, followed by grassland and farmland landscapes.


Assuntos
Conservação dos Recursos Naturais/estatística & dados numéricos , Produtos Agrícolas/crescimento & desenvolvimento , Ecossistema , Poaceae/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , China , Conservação dos Recursos Naturais/métodos , Sistemas de Informação Geográfica , Reprodutibilidade dos Testes , Comunicações Via Satélite
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