| 1. |
- Bai, Xiaohang, et al.
(författare)
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Precipitation drives the floristic composition and diversity of temperate grasslands in China
- 2021
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Ingår i: Global Ecology and Conservation. - : Elsevier BV. - 2351-9894. ; 32
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Tidskriftsartikel (refereegranskat)abstract
- Effects of environmental factors on plant diversity in temperate grasslands are of interest since experiments have found plant diversity is related to ecosystem function. Although previous studies have focused on the effects of environmental factors on plant diversity, the dominant environmental factors driving diversity differences among plant community types in temperate grasslands at regional scale remains unclear. We established 38 sampling sites (45 m x 45 m) in the main distribution areas of temperate grasslands to analyze the responses of plant community along different environmental gradients and identifies the dominant environmental factors driving the floristic composition and diversity in Inner Mongolia, China. In addition, environmental variables (annual mean temperature, annual precipitation, altitude, disturbance intensity, soil pH, soil density, soil water content, soil organic carbon, soil total nitrogen, soil total phosphorus, soil calcium carbonate), species diversity indices (richness, heterogeneity, evenness), functional diversity indices (abundance, evenness, divergence, dispersion) and plant biomass were analyzed. A total of 179 vascular plant species belonging to 43 families and 113 genera were recorded and classified into six plant community types (Stipa grandis community, Leymus chinensis community, Stipa capillata community, Artemisia frigida community, Cleistogenes squarrosa community, Artemisia halodendron community) based on Ward's agglomerative hierarchical clustering. According to canonical correspondence analysis and Monte Carlo permutation test, mean annual precipitation was the dominant environmental factor driving temperate grasslands, promoting species richness, heterogeneity, evenness, functional divergence and biomass. Soil organic carbon, water content and total nitrogen played positive effects on species diversity, meanwhile, mean annual temperature, altitude, grazing intensity and soil pH inhibited species diversity, functional abundance, dispersion and biomass. Furthermore, the presence of these plant communities dominated by Cleistogenes squarrosa and Artemisia halodendron indicate that grassland degradation is imminent or has already begun. In summary, our results provide evidence on the responses of composition, functional traits and biomass among different plant community types to environmental factors and demonstrate that precipitation is the dominant factors driving the floristic composition and diversity in temperate grasslands.
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| 2. |
- Bai, Xiaohang, et al.
(författare)
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Reducing plant community variability and improving resilience for sustainable restoration of temperate grassland
- 2022
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Ingår i: Environmental Research. - : Elsevier BV. - 0013-9351 .- 1096-0953. ; 207
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Tidskriftsartikel (refereegranskat)abstract
- Grassland ecosystem is important for the realization of the global sustainable development goals (e.g. Goal 15) since it provides irreplaceable services for human beings, supporting human health and sustainable development. Most studies have focused on improving grassland restoration techniques, but less attention has been paid to grassland ecosystem stability in succession. Plant community stability of temperate grassland in arid and semi-arid regions is analyzed through 38 sampling sites in Inner Mongolia, China. The degradation succession sequence of grassland is established by principal component analysis, and the species diversity and functional diversity along degradation gradient analyzed by multivariate statistical analysis. The results show that (1) functional diversity has higher explanatory power for community stability than species diversity due to the functional dispersion of plant traits; (2) climate factors rather than grazing or soil control plant community diversity and stability at regional scale; (3) the resistance of plant community does not change in degradation succession, but the trade-off effect of stability components in different plant communities differ, such as the order of trade-off effects (e.g. community resilience (ET)＞community resistance (RT)＞structural variability (St)＞functional variability (Fu) in the community dominated by Stipa grandis, RT＞ET＞St＞Fu in Leymus chinensis community, St＞ET＞Fu＞RT in Stipa capillata community, RT＞St＞Fu＞ET in Artemisia frigida community, St＞Fu＞ET＞RT in Cleistogenes squarrosa community, and Fu＞St＞RT＞ET in Artemisia halodendron community); (4) grassland ecosystem with higher diversity shows greater resilience and lower variability than those with single species, which supports the established diversity hypothesis. Furthermore, sustainable grassland restoration should reduce community variability and improve resilience. These findings highlight the response of diversity to stability in temperate grassland and provide scientific support for grassland ecosystem protection and restoration.
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| 3. |
- Ning, Yongling, et al.
(författare)
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β-Glucan restores tumor-educated dendritic cell maturation to enhance antitumor immune responses.
- 2016
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136. ; 138:11, s. 2713-2723
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Tidskriftsartikel (refereegranskat)abstract
- Tumors can induce the generation and accumulation of immunosuppressive cells such as myeloid-derived suppressor cells (MDSCs) in a tumor microenvironment, contributing to tumor escape from immunological attack. Although dendritic cell-based cancer vaccines can initiate antitumor immune responses, tumor-educated dendritic cells (TEDCs) involved in the tolerance induction have attracted much attention recently. In this study, we investigated the effect of β-glucan on TEDCs and found that β-glucan treatment could promote the maturation and migration of TEDCs and that the suppressive function of TEDCs was significantly decreased. Treatment with β-glucan drastically decreased the levels of regulatory T (Treg) cells but increased the infiltration of macrophages, granulocytes and DCs in tumor masses, thus elicited Th1 differentiation and cytotoxic T-lymphocyte responses and led to a delay in tumor progression. These findings reveal that β-glucan can inhibit the regulatory function of TEDCs, therefore revealing a novel function for β-glucan in immunotherapy and suggesting its potential clinical benefit. β-Glucan directly abrogated tumor-educated dendritic cells-associated immune suppression, promoted Th1 differentiation and cytotoxic T-lymphocyte priming and improved antitumor responses. This article is protected by copyright. All rights reserved.
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