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Grazing impact on forage quality and macronutrient content of rangelands in Qilian Mountains, NW China

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Journal of Mountain Science 2019年第1期16卷 43-53页

作者： Alina BARANOVA Jens OLDELAND WANG Shun-li udo SCHICKHOFF CEN Center for Earth System Research and Sustainability Institute of Geography University of Hamburg Biodiversity Ecology and Evolution of Plants Biocenter Klein Flottbek and Botanical Garden University of Hamburg Academy of Water Resource Conservation Forest of Qilian Mountains (AWRCFQM)

An important indicator of the rangeland health, associated with land degradation, is the ability of semi-natural rangelands to provide forage of sufficient quality for livestock production. In Qilian Mountains(Gansu Province, NW China) biomass production and forage quality are dependent on the seasonality of precipitation and temperature; most of the precipitation falls during summer season, when sheep, goats and yaks graze mountain rangelands. To sustain the rangelands and to improve the management strategies, the assessment of the forage quality should be implemented. The purpose of this research was to study the response of biomass, forage quality and macronutrient content different levels of grazing intensity in Qilian rangelands. We sampled aboveground biomass in the growing seasons in 2012 and 2013 within spring/autumn or summer grazing regimes in two altitudinal zones below and above 3000 m a.s.l.(montane-subalpine and subalpine-alpine respectively). In order to estimate forage quality, biomass was sampled in 1 m × 1 m plots, assigned to the center of 10 ×10 m sites, fromwhich we collected different indicator parameters of rangeland health. Mineral and fiber content of forage biomass was estimated under different levels of grazing intensity with regard to the growing period. It was found that an increase in grazing intensity led to a decrease in dry matter weight. No linearity was observed in the relationship between nutritive value and grazing intensity. The highest fiber content(59.20 %) was found in plots mostly disturbed by grazing. The highest protein(16.30 %) and the lowest fiber(51.30 %) contents were associated with slightly grazing intensity. Concentrations of the mineral elements, such as Zn, P, K and S varied significantly and showed maximum values under low grazing intensity.

关键词： Grazing intensity Nutritive value Forage quality Mineral concentrations Alpine,Subalpine pastures

Key Factors Involved in Lamb Quality from Farm to Fork in Europe

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Journal of Integrative Agriculture 2013年第11期12卷 1919-1930页

作者： Carlos Saudo Erica Muela María del Mar Campo Department of Animal Production and Food Science University of Zaragoza

World lamb consumption is approximately 2 kg per capita with large variations between continents, e.g., 17 kg in Oceania vs. 0.7 kg in North America. With less than one million tonnes, the international trade of sheep meat contributes to a small percentage of the total meat exchanged between countries. On the other hand, lamb represents the highest rate of species trading in relation to the total sheep meat produced. It is therefore likely to ifnd a wide variability of different lamb products in the same market, and that the conservation procedures （such as refrigeration, packaging or freezing）, chemical composition, especially the fat due to its implication in human health, lfavour development and juiciness perception （affected, i.e., by the feeding or the age or slaughter weight of the animal） and acceptability （based on culinary background） could be considered important indicators of this advantageous situation. In this paper some studies related to the aforementioned indicators are discussed.

关键词： technology chemical composition consumer preferences

Rangeland degradation assessment in Kyrgyzstan:vegetation and soils as indicators of grazing pressure in Naryn Oblast

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Journal of Mountain Science 2016年第9期13卷 1567-1583页

作者： HOPPE Franziska ZHUSUI KYZY Taalaigul USUPBAEV Adilet SCHICKHOFF udo CEN Center for Earth System Research and Sustainability Institute of Geography Laboratory of "Flora" Institute for Biology and Pedology National Academy of Sciences of the Kyrgyz Republic

Rangelands occupy more than 80% of the agricultural land in Kyrgyzstan. At least 30% of Kyrgyz pasture areas are considered to be subject to vegetation and soil degradation. Since animal husbandry is the economic basis to sustain people's livelihoods, rangeland degradation presents a threat for the majority of the population. We present for the first time an ecological assessment of different pasture types in a remote area of the Naryn Oblast, using vegetation and soils as indicators of rangeland conditions. We analysed the current degree of utilization(grazing pressure), the amount of biomass, soil samples, and vegetation data, using cluster analysis as well as ordination techniques. Winter pastures(kyshtoo) are characterized by higher p H values(average of 7.27) and lower organic matter contents(average of 12.83%) compared to summer pastures(dzailoo) with average p H values of 6.03 and average organic matter contents of 21.05%. Additionally, summer pastures show higher aboveground biomass, and higher species richness anddiversity. Our results support the hypothesis that winter pastures, which are located near settlements, suffer from over-utilisation, while the more distant summer pastures are subjected to much lower grazing pressure.

关键词：吉尔吉斯斯坦放牧压力土壤退化草地退化植被退化评价有机质含量地上生物量

Numerical studies of the Kelvin-Hemholtz instability in a coronal jet

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Research in Astronomy and Astrophysics 2018年第4期18卷 91-104页

作者： Tian-Le Zhao Lei Ni Jun Lin udo Ziegler Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China University of Chinese Academy of Sciences Beijing 100049 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100101 China Leibniz-Institut fur Astrophysik Potsdam Potsdam D-14482 Germany

Kelvin-Hemholtz（K-H）instability in a coronal EUV jet is studied via 2.5D MHD numerical *** jet results from magnetic reconnection due to the interaction of the newly emerging magnetic field and the pre-existing magnetic field in the *** results show that the Alfv e′n Mach number along the jet is about 5–14 just before the instability occurs,and it is even higher than 14 at some local *** the K-H instability process,several vortex-like plasma blobs with high temperature and high density appear along the jet,and magnetic fields have also been rolled up and the magnetic configuration including anti-parallel magnetic fields forms,which leads to magnetic reconnection at many X-points and current sheet fragments inside the vortex-like *** magnetic islands appear inside the main current sheet,the total kinetic energy of the reconnection outflows decreases,and cannot support the formation of the vortex-like blob along the jet any longer,then the K-H instability eventually *** also present the results about how the guide field and flux emerging speed affect the K-H *** find that a strong guide field inhibits shock formation in the reconnecting upward outflow regions but helps secondary magnetic islands appear earlier in the main current sheet,and then apparently suppresses the K-H *** the speed of the emerging magnetic field decreases,the K-H instability appears later,the highest temperature inside the vortex blob gets lower and the vortex structure gets smaller.

关键词： Sun corona jet — Kelvin-Hemholtz instability — guide-field — method numerical simulations

Evolution of germination strategy in the invasive species Ulex europaeus

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Journal of Plant Ecology 2017年第2期10卷 375-385页

作者： Nathalie udo Michèle Tarayre Anne Atlan Laboratoire ECOBIO UMR 6553CNRSUniversitéde Rennes 1Bâtiment 14ACampus de Beaulieu263 avenue du Général Leclerc35042 Rennes CedexFrance

Aims The study of the adaptive potential of the germination patterns of invading species enables us to identify some traits linked with their capacity to colonize new sites,and to gain a better understanding of their area of *** aim of this study is to determine the germination pattern of Ulex europaeus,a cosmopolitan invasive species,in relation to temperature and to explore its potential evolu-tion and invasiveness in a tropical region,following its introduction from *** We studied the germination pattern of ***(the com-mon gorse)to test both physical dormancy and germination capacity within the range of temperatures found in the native and invasive *** understand its germination pattern and its evolution,the rate and the speed of germination,as well as the percentage of seeds that became mouldy during the experi-ment,have been compared between a native habitat,France and a habitat into which it has been introduced,the tropical island of La *** Findings The results show that gorse seeds germinate in large quantities,pos-sess the ability to germinate under a wide range of temperatures and they confirm the physical dormancy of the seeds(caused by seed coat impermeability).The decrease in germination from 25℃ upwards,coupled with an increase in the rate of moulding help to explain its restricted distribution at altitude in tropical *** scari-fied seeds,we have not detected any difference between the two regions,neither in the percentage of germinated seeds,nor in the per-centage of mouldy ***,seeds from Reunion germinate faster at 20℃ than seeds from France and a greater number of seeds from Reunion are able to germinate without scarification(10-60%for Reunion versus 0-10%for France).These results suggest that while preserving the advantages of the native habitat,in Reunion gorse develops a strategy which favours the rapid occupation of new sites.

关键词： Ulex europaeus invasive species germination physical dormancy

Mammal Species Composition in Ini Local Government Area, Akwa Ibom State, Nigeria

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Natural Resources 2022年第9期13卷 181-189页

作者： Abraham Adebayo Adewumi Albert Jeremiah udo Gbolagade Akeem Lameed Department of Wildlife and Ecotourism Management College of Agriculture Osun State University Osogbo Nigeria Department of Wildlife and Ecotourism Management University of Ibadan Ibadan Nigeria

Ini Local Government Area (ILGA) is the home of biodiversity, rich in many species of fauna and flora. However, anthropogenic activities carried out by the inhabitants of this area have been a threat to the ecosystem, thereby exterminating the wildlife resources. The data for this study were collected from in-depth interviews with hunters, bushmeat markets, bushmeat sellers, indirect and direct wildlife survey methods, and a semi-structured questionnaire was employed for the household survey. A multiple sampling technique was adopted. A stratified random sampling technique was utilized to stratify the study area into six strata (clans). A proportional sampling technique was used to select 11 villages. In contrast, 60 household heads were randomly selected for questionnaire administration. The study revealed seventeen (17) species of mammal, which accounted for four orders, with Rodentia being the highest (47%). Most species (94%) had the conservation status of Least Concern (LC) based on the IUCN Red List of Threatened Species. Furthermore, illegal hunting and deforestation for agriculture and infrastructural development in the area have led to the loss of wildlife habitats. Thus, a great need for conservation and management practices to protect these vulnerable mammals and their habitats is needed. Hunting laws, afforestation, and reforestation programs should be implemented.

关键词： Habitat Ini LGA Mammal Wildlife Conservation Species

The Ellerman bomb and ultraviolet burst triggered successively by an emerging magnetic flux rope

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Research in Astronomy and Astrophysics 2021年第9期21卷 163-179页

作者：程冠冲倪蕾陈亚杰 udo Ziegler 林隽 Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of Solar Activity National Astronomical ObservatoriesBeijing 100101China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China School of Earth and Space Sciences Peking UniversityBeijing 100871China Astrophysikalisches Institut Potsdam D-14482 Potsdam Germany

Ellerman bombs(EBs)and ultraviolet(UV)bursts are common brightening phenomena,which are usually generated in the low solar atmosphere of emerging flux *** this paper,we have investigated the emergence of an initial un-twisted magnetic flux rope based on three-dimensional(3 D)magneto-hydrodynamic(MHD)*** EB-like and UV burst-like activities successively appear in the U-shaped part of the undulating magnetic fields triggered by the Parker *** EB-like activity starts to appear earlier and lasts for about 80 *** minutes later,a much hotter UV burstlike event starts to appear and lasts for about 60 *** the direction vertical to the solar surface,both the EB and UV burst start in the low chromosphere,but the UV burst extends to a higher altitude in the up *** regions with apparent temperature increase in the EB and UV burst are both located inside the small twisted flux ropes generated in magnetic reconnection processes,which are consistent with the previous 2 D simulations that most hot regions are usually located inside the magnetic ***,the twisted flux rope corresponding to the EB is only strongly heated after it floats up to an altitude much higher than the reconnection site during that *** analyses show that the EB is heated by the shocks driven by the strong horizontal flows at two sides of the U-shaped magnetic *** twisted flux rope corresponding to the UV burst is heated by the driven magnetic reconnection process.

关键词： magnetic reconnection (magnetohydrodynamics)MHD shocks Sun:heating Sun:low solar atmosphere Sun:magnetic flux emergence

Numerical experiments of disturbance to the solar atmosphere caused by eruptions

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Science China(Physics,Mechanics & Astronomy) 2012年第7期55卷 1316-1329页

作者： MEI ZhiXing udo Ziegler LIN Jun Yunnan Astronomical Observatory Chinese Academy or'SciencesP.O.Box 110Kunming 650011China Graduate University of the Chinese Academy of Sciences Beijing 100049China Leibniz-lnstitut filer A strophysik Potsdam Potsdam D-14482Germany Harvard-Smithsonian Center for Astrophysics 60 Garden StreetCambridge 02138USA

Despite extensive research on various global waves in solar eruptions, debate continues on the intrinsic nature of them. In this work, we performed numerical experiments of the coronal mass ejection with emphases on the associated large-scale MHD waves. A fast-mode shock forms in front of the flux rope during the eruption with a dimming region following it, and the development of a three-component structure of the ejecta is observed. At the flank of the flux rope, the slow-mode shock and the velocity vortices are also invoked. The dependence of the eruption energetics on the strength of the background field and the coronal plasma density distribution is apparent: the stronger the background field is, and/or the lower the coronal plasma density is, the more energetic the eruption is. In the lower Alfve′n speed environment, the slow mode shock and the large scale velocity vortices may be the source of the EIT wave. In the high Alfve′n speed environment, on the other hand, the echo due to the reflection of the fast shock on the bottom boundary could be so strong that its interaction with the slow mode shock and the velocity vortices produces the second echo propagating downward and causing the secondary disturbance to the boundary surface. We suggest that this second echo, together with the slow shock and the velocity vortices, could constitute a possible candidate of the source for the EIT wave.

关键词：火山喷发太阳爆发数值试验大气干扰日冕物质抛射等离子体密度企业所得税密度分布

Complications of newborn enterostomies

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World Journal of Clinical Cases 2018年第16期6卷 1101-1110页

作者： Lea Wolf Stefan Gfroerer Henning Fiegel udo Rolle Department of Pediatric Surgery University Hospital Frankfurt Goethe-University Frankfurt am Main

AIM To evaluate the occurrence and severity of enterostomy complications in newborns suffering from different intestinal *** A 10-year retrospective cohort study(2008-2017) investigated newborns that underwent enterostomy formation and reversal for different intestinal disorders. Only infants less than 28 d old at the time of enterostomy creation were included in the study(corrected age was applied in the cases of preterm neonates). The patients were divided into two groups according to their underlying diseases. Group 1 included infants suffering from necrotizing enterocolitis(NEC), whereas Group 2 included newborns diagnosed with intestinal disorders other than NEC, such as meconium obstruction, anorectal malformation, focal intestinal perforation, ileus, intestinal atresia and volvulus. The primary outcome measure was enterostomy-related morbidity. The data were analyzed statistically using Pearson's χ2 test or Fisher's exact test for categorical variables and the Wilcoxon-Mann-Whitney U-Test for continuous variables. RESULTS In total, 76 infants met the inclusion criteria and were evaluated for enterostomy-related complications. Neither group showed significant differences regarding gender, gestational age, weight at birth or weight at enterostomy formation. Infants suffering from NEC(Group 1) were significantly older at enterostomy for-mation than the neonates of Group 2 [median(range), 11(2-75) d vs 4(1-101) d, P = 0.004)]. Significantly more ileostomies were created in Group 1 [47(92.2%) vs 16(64.0%), P = 0.007], whereas colostomies were performed significantly more often in Group 2 [2(3.9%) vs 8(32.0%), P = 0.002]. The initiation of enteral nutrition after enterostomy was significantly later in Group 1 infants than in Group 2 infants [median(range), 5(3-13) vs 3(1-9), P < 0.001]. The overall rate of one or more complications in patients of both groups after enterostomy formation was 80.3%, with rates of 86.3% in Group 1 and 68.0% in Group 2(P =

关键词： Enterostomy closure Enterostomy Stoma Necrotizing enterocolitis Neonates Complications Enterostomy formation