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Susceptibility of dairy cows to subacute ruminal acidosis is reflected in both prepartum and postpartum bacteria as well as odd-and branched-chain fatty acids in feces

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Journal of animal Science and Biotechnology 2023年第1期14卷 229-243页

作者： Hong Yang Stijn Heirbaut Xiaoping Jing Nympha De Neve Leen Vandaele Jeyamalar Jeyanathan Veerle Fievez Laboratory for animal Nutrition and animal Product Quality Department of Animal Sciences and Aquatic EcologyFaculty of Bioscience EngineeringGhent UniversityCampus Coupurebuilding F1st floorCoupure Links 6539000 GhentBelgium. State Key Laboratory of grassland and Agro‑Ecosystems International Centre for Tibetan Plateau Ecosystem ManagementSchool of Life SciencesLanzhou UniversityLanzhou 730000China. animal Sciences Unit Flanders Research Institute for AgricultureFisheries and FoodScheldeweg 689090 MelleBelgium.

Background:The transition period is a challenging period for high-producing dairy *** in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility in early lactation is hypothesized to be reflected in fecal characteristics such as fecal pH,dry matter content,volatile and odd-and branched-chain fatty acids(VFA and OBCFA,respectively),as well as fecal *** was investigated with 38 periparturient dairy cows,which were classified into four groups differing in median and mean time of reticular pH below 6 as well as area under the curve of pH below ***,we investigated whether fecal differences were already obvious during a period prior to the SARA risk(prepartum).Results:Variation in reticular pH during a 3-week postpartum period was not associated with differences in fecal pH and VFA *** the postpartum period,the copy number of fecal bacteria and methanogens of unsusceptible(UN)cows was higher than moderately susceptible(MS)or susceptible(SU)cows,while the genera Ruminococcus and Prevotellacea_UCG-001 were proportionally less abundant in UN compared with SU ***,only a minor reduction was observed in iso-BCFA proportions in fecal fatty acids of SU cows,particularly iso-C15:0and iso-C16:0,compared with UN *** with the bacterial changes postpartum,the lower abundance of Ruminococcus was already observed in the prepartum fecal bacterial communities of UN cows,whereas Lachnospiraceae_UCG-001 was ***,no differences were observed in the prepartum fecal VFA or OBCFA profiles among the *** fecal bacterial communities of cows were clustered into two distinct clusters with 70%of the SU cows belonging to cluster 1,in which they represented 60%of the ***:Inter-animal variation in postpartum SARA susceptibility was reflected in post-and prepartum fecal bacterial *** in prepartum fecal bacte

关键词： Fecal bacterial community Fecal odd-and branched-chain fatty acids Inter-animal variation Subacute ruminal acidosis

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Relative importance of spatial processes and environmental factors in shaping alpine meadow communities

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Journal of Plant ecology 2011年第4期4卷 249-258页

作者： Qi Li Xue Yang Janne Soininen Cheng-Jin Chu Jie-Qi Zhang Kai-Liang Yu Gang Wang MOE Key Laboratory of Arid and grassland ecology Lanzhou UniversityLanzhou 730000China department of Environmental Sciences University of HelsinkiHelsinkiPO Box 65FI 00014Finland

Spatial processes and environmental control are the two distinct,yet not mutually exclusive forces of community structuring,but the relative importance of these factors is controversial due to the speciesspecific dispersal ability,sensitivity towards environmental variables,organism’s abundance and the effect of spatial *** the present paper,we explored spatial versus environmental control in shaping community composition(i.e.b-diversity)and species turnover(*** of b-diversity)at an alpine meadow along a slope aspect gradient on the Qinghai–Tibetan Plateau at different spatial scales of sampling(quadrats and plots),by taking account of seed dispersal mode and *** We examined the relative importance of spatial processes and environmental factors using all species and four additional subsets of selected ***,we attempted to explore the effect of scale(quadrat refers to scale of;0.3 m and plot of;8 m)on their counter *** data were analyzed both by variation partitioning and multiple regressions on distance *** spatial structure was modelled using Moran’s eigenvector maps(MEM).Important Findings Both spatial processes and environmental factors were important determinants of the community composition and species *** community composition in the alpine meadow was controlled by spatially structured environment(17.6%),space independent of environment(18.0%)and a negligible effect of environment independent of space(4.4%)at the scale of *** three components contributed 21.8,9.9 and 13.9%,respectively,at the scale of *** balance between the forces at different spatial scales drove community structures along the slope aspect *** importance of environmental factors on b-diversity at alpine meadow increased with scale while that of spatial processes decreased or kept steady,depending on dispersal mode and abundance of species comprising the *** the‘pure’effect of spatial processes on

关键词： alpine meadow dispersal environmental factor slope aspect spatial process spatial scale

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Vocal performance reflects individual quality in male Great Himalayan leaf-nosed bats(Hipposideros armiger)

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Integrative Zoology 2022年第5期17卷 731-740页

作者： Congnan SUN Chunmian ZHANG Jeffrey RLUCAS Hao GU Jiang FENG Tinglei JIANG Jilin Provincial Key Laboratory of animal Resource Conservation and Utilization Northeast Normal UniversityChangchunChina Key Laboratory of Vegetation ecology of Education Ministry Institute of Grassland ScienceNortheast Normal UniversityChangchunChina department of Biological Sciences Purdue UniversityWest LafayetteUSA College of Life Science Jilin Agricultural UniversityChangchunChina

Signals containing parameter trade-offs are likely to be honest indicators of signaler quality because they are difﬁcult to *** with a trill-rate/bandwidth trade-off have been described for many songbird species,one mouse,and one non-human primate ***,there were no reports about whether there is a vocal performance trade-off in social calls of *** study investigated(1)a possible vocal performance trade-off in territorial calls of male Great Himalayan leaf-nosed bats,Hipposideros armiger,recorded from 9 locations in south China,and(2)the relationships between vocal performance(vocal deviation and consistency)and caller’s quality(body mass)to determine whether vocal performance honestly indicates a caller’s *** deviation measures the deviation of a call relative to an extreme call and vocal consistency measures the spectral consistency across a string of *** results showed a signiﬁcant negative correlation between syllable repetition rate and frequency bandwidth,suggesting a vocal performance trade-off similar to the one in ***,there was a signiﬁcant negative relationship between body mass and vocal deviation,but no signiﬁcant correlation between body mass and vocal *** study provides theﬁrst empirical evidence for a vocal performance trade-off of social calls in bats,and the potential for the level of performance to indicate caller quality.

关键词： bats male quality territorial calls trade-off vocal performance

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Mismatch between species distribution and climatic niche optima in relation to functional traits

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Forest Ecosystems 2022年第6期9卷 813-822页

作者： Zhenghua Lian Juan Wang Chunyu Zhang Xiuhai Zhao Klaus von Gadow Research Center of Forest Management Engineering of State Forestry and grassland Administration Beijing Forestry UniversityBeijing100083China department of Forest ecology School of Ecology and Nature ConservationBeijing Forestry UniversityBeijing100083China Faculty of Forestry and Forest ecology Georg-August-University GottingenBüsgenweg 5D-37077GottingenGermany department of Forest and Wood Science University of StellenboschStellenbosch7600South Africa

Background:Forecasts of climate change impacts on biodiversity often assume that the current geographical distributions of species match their niche ***,empirical evidence has challenged this assumption,suggesting a *** examine whether the mismatch is related to functional traits along temperature or precipitation ***:The observed distributions of 32 tree species in northeast China were evaluated to test this *** models were used to estimate the climatic niche optima,*** habitats where the highest species growth and density can be *** mismatch is defined as the difference between the actual species occurrence in an assumed niche optimum and the habitat with the highest probability of species ***’functional traits were used to explore the mechanisms that may have caused the ***:Contrasting these climatic niche optima with the observed species distributions,we found that the distribution-niche optima mismatch had high variability among species based on temperature and precipitation ***,these mismatches depended on functional traits associated with competition and migration lags only in temperature ***:We conclude that more relevant research is needed in the future to quantify the mismatch between species distribution and climatic niche optima,which may be crucial for future designs of forested landscapes,species conservation and dynamic forecasting of biodiversity under expected climate change.

关键词： Demography Functional traits Mean annual temperature Mean annual precipitation Niche theory Species distribution

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Responses of grazing households to different levels of payments for ecosystem services

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Ecosystem Health and Sustainability 2022年第1期8卷 50-64页

作者： Weiwei Shen Ting Zhou Hong Chang Xiao Qiu Yahong Liu Hailian Sun Xiu Zhai Hongbo Yang Guihuan Liu Wu Yang Center for Intelligent ecology and Sustainability College of Environmental and Resource SciencesZhejiang UniversityHangzhouZhejiangChina Inner Mongolia Academy of Agriculture and animal husbandry HohhotChina Global Development Policy Center Boston UniversityBostonMassachusettsUSA Chinese Academy of Environmental Planning BeijingChina

Introduction:Payments for Ecosystem Services(PES)programs have been implemented globally to protect ecosystems while securing the well-being of affected *** payment standards are key to successful PES *** some approaches are available for determining payment standards,few studies have applied them for grassland conservation with location indicators and socioeconomic contexts properly ***:Using China’s first pilot grassland Ecological Compensation Policy(GECP)as an example,we analyzed the effects of payment levels,other natural and socioeconomic factors on herders’willingness to participate in the GECP in Damao County in Inner Mongolia where grassland degradation is happening at an alarming rate due to overgrazing and cropland ***:Our results show that households with lower herding income,older age,higher education,larger grassland areas,and worse social relationships are more inclined to participate in the *** payment level,as well as natural and socioeconomic contextual factors,significantly affect the response of herdsmen,and a reasonable grassland payment standard with a 95%policy compliance rate should be 8.8 yuan *** and Conclusion:Our findings can inform governments to develop effective PES programs to balance the need of human well-being improvement and grassland conservation in China and beyond.

关键词： Conservation grassland ecosystem grassland compensation ecological compensation standard ecosystem management:poverty alleviation

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Structure complexity is the primary driver of functional diversity in the temperate forests of northeastern China

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Forest Ecosystems 2022年第4期9卷 511-520页

作者： Zhenghua Lian Juan Wang Chunyu Fan Klaus von Gadow Research Center of Forest Management Engineering of State Forestry and grassland Administration Beijing Forestry UniversityBeijing100083China department of Forest ecology School of Ecology and Nature ConservationBeijing Forestry UniversityBeijing100083China Faculty of Forestry and Forest ecology Georg-August-University G€ottingenBüsgenweg 5D-37077GottingenGermany department of Forest and Wood Science University of StellenboschStellenbosch7600South Africa

Background:Assessing functional diversity to identify its spatial patterns and drivers is an important step towards understanding the adaptive capacity of ecosystems to environmental change. However, until now, these mechanisms were poorly understood in the temperate forests of northeastern China, which prevented the development of new management methods aimed at increasing functional trait diversity and thus ecological ***:In this study, we mapped functional diversity distributions using a Kriging Interpolation Method. A specific random forest model approach was adopted to test the importance ranking of 18 variables in explaining the spatial variation of functional diversity. Three piecewise structural equation models (pSEMs) with forest types as random effects were constructed for testing the direct effects of climate, and the indirect effects of stand structure on functional diversity across the large study region. Specific causal relationships in each forest type were also examined using 15 linear structural equation ***:Although environmental filtering by climate is important, stand structure explains most of the functional variation of the forest ecosystems in northeastern China. Our study thus only partially supports the stressdominance hypothesis. Several abundant species determine most of the functional diversity, which supports the mass ratio ***:Our results suggest that forest management aimed at increasing structural complexity can contribute to increased functional diversity, especially regarding the mixing of coniferous and broad-leaved tree species.

关键词： Functional diversity distribution Forest types Forest management Random forest Stand structure attributes Structural equation modeling

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Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem

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Journal of Mountain Science 2024年第1期21卷 146-159页

作者： HAO Aihua LUO Zhengming CHEN Xiaojiang department of Geography Xinzhou Normal UniversityXinzhou 034000China department of Biological Sciences Xinzhou Normal UniversityXinzhou 034000China

Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatm

关键词： Warming effect Plant diversity pattern Community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai

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Divergent patterns of foliar δ^(13)C and δ^(15)N in Quercus aquifolioides with an altitudinal transect on the Tibetan Plateau: an integrated study based on multiple key leaf functional traits

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Journal of Plant ecology 2015年第3期8卷 303-312页

作者： Litong Chen Dan F.B.Flynn Xiaowei Zhang Xianliang Gao Ling Lin Jian Luo Changming Zhao State Key Laboratory of grassland Agro-Ecosystems School of Life SciencesLanzhou UniversityLanzhou 730000GansuChina Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008QinghaiChina College of Tibet Agriculture and animal husbandry Tibetan UniversityNyingchi 860000TibetChina

Aims With a close association with plant water availability,foliar δ^(13)C had been investigated extensively in alpine regions;however,foliar δ^(15)N has rarely been concurrently used as an indicator of plant nitrogen *** to the positive correlations between leaf nitrogen con-tent and foliar δ^(13)C andδ15N found in previous studies,we expected that they should show consistent patterns along an altitudinal *** To test our hypothesis,we measured foliar δ^(13)C andδ15N in conjunc-tion with multiple key leaf functional traits of Quercus aquifolioides,a dominant species of alpine forest on the eastern slopes of the sygera mountains,southeastern Tibetan Plateau from 2500 to 3800 *** findings(i)Contrary to our hypothesis,foliar δ^(13)C exhibited a significant pos-itive linear relationship with altitude;in contrast,foliarδ15N initially increased and subsequently decreased with altitude,the change in trend occurring around 3300 m.(ii)our analyses indicated that leaf internal resistance and stomatal conductance,rather than photosynthetic capacity indicated by leaf N concentration,appar-ently explained the altitudinal variation in foliar δ^(13)C,while differ-ences in foliar δ^(15)N were likely the result of soil N availability.(iii)Principal component analysis revealed a clear association between δ^(13)C and a tradeoff between water loss and carbon gain,indicated by traits related to gas exchange such as leaf thickness,density,sto-matal *** contrast,the second axis was associated withδ15N and nitrogen acquisition strategy in *** across its altitudinal distribution,represented by traits related to nitrogen concentration and stomata per gram of leaf nitrogen.

关键词： elevation carbon and nitrogen isotopes leaf internal resistance leaf mass per unit area(LMA) stomatal conductance trade-off

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Sward Structural Characteristics and Performance of Beef Heifers Reared under Rotational Grazing Management on Campos grassland

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American Journal of Plant Sciences 2014年第7期5卷 1020-1029页

作者： Cezar Wancura Barbieri Fernando Luiz F. de Quadros Felipe Jochims émerson Mendes Soares Leandro Bittencourt de Oliveira Régis Maximiliano R. Carvalho Gabriela Machado Dutra Felipe Xavier de Lima Franciele Gusatto Natural grassland ecology Research Group (LEPAN-UFSM) Universidade Federal de Santa Maria Animal Science Department Santa Maria Brazil

This study aimed to evaluate the effect of two rest intervals on structural sward characteristics and productive performance of beef heifers reared on Campos grassland managed on rotational grazing. The treatments were two intervals between grazing of 375 and 750 DD (degree days), based on thermal cumulative sum for leaf expansion of native grasses belonging to two functional groups. The experimental design was a randomized complete block design with two treatments and three replications. The tested animals were beef heifers with initial age of 12 months and average weight of 185.2 ± 17.4 kg. Measures in the pasture were: herbage mass, mass of green leaf blades, stem mass, dead material mass and green leaf allowance. The 750 DD rest interval presented higher herbage mass (24%), higher green herbage mass and 19% more leaves in the canopy. This rest interval also presents a high proportion of dead material and stems in the sward structure. In the other way, the 375 DD rest interval presents better chemical characteristics, with 20% more crude protein in the hand plucking samples. Heifers’ dry matter intake was similar between the rest intervals (2.04% of live weight) and the bite mass was also similar (0.22 g DM per bite) but the animal performance was higher in the 375 DD rest interval. The stocking density showed similarity between treatments with an average of 875 kg/LW/ha. The live weight gain per area was higher in 40 kg/LW/ha (P = 0.117) for 375 DD rest interval, reaching 251 kg/LW/ha produced over the 149 experimental days. Based on these results, we can conclude that the treatment of shortest interval between defoliation gave the highest gain individual animals in warm seasons.

关键词： Average Daily Gain Duration of Leaf Expansion Herbage Mass Rotational Grazing Stocking Rate

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Cultivated grassland Development on the Tibetan Plateau:Current Status,Challenges,Suggestions

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Journal of Resources and ecology 2024年第4期15卷 804-813页

作者： HOU Ge SHI Peili ZHAO Guangshuai CHEN Xueying HUANG Xiaofang DUAN Cheng Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Development Research Center National Forestry and Grassland AdministrationBeijing 100714China University of Chinese Academy of sciences Beijing 100049China

The Tibetan Plateau is vital for animal husbandry in China,and relies heavily on its natural ***,grassland degradation,increasing livestock numbers,and uneven grazing practices are exacerbating the grass-livestock *** grasslands are a key strategy to address this *** this review,we evaluate the current status,challenges,and suggestions for developing and managing Tibetan Plateau cultivated *** discernible advancements have been made in the cultivated grasslands in this region,persistent challenges *** challenges stem from issues like low awareness and enthusiasm among farmers and herders,uneven cultivated grassland distribution,and limited scientific and technological *** on these challenges,we propose strengthening the promotion of artificial forage,implementing a rationalized grassland layout,and improving the scientific and technological contributions to forage species selection,sowing,management,and *** summary,cultivated grasslands in the Tibetan Plateau offer promising prospects but still face significant *** these obstacles will require innovative approaches to unlock the full potential of cultivated grasslands in this unique ecological niche.

关键词： animal husbandry balance of grass and livestock cultivated grassland Tibetan Plateau

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