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163篇 您的检索式:作者名="Ci Zhang"
    题名 作者 年代 出处 被引量
1Phosphorus recovery from biogas fermentation liquid by Ca-Mg loaded biochar显示文摘Shortage in phosphorus(P) resources and P wastewater pollution is considered as a serious problem worldwide. The application of modified biochar for P recovery from wastewater and reuse of recovered P as agricultural fertilizer is a preferred process. This work aims to develop a calcium and magnesium loaded biochar(Ca–Mg/biochar) application for P recovery from biogas fermentation liquid. The physico-chemical characterization, adsorption efficiency, adsorption selectivity, and postsorption availability of Ca-Mg/biochar were investigated. The synthesized Ca–Mg/biochar was rich in organic functional groups and in Ca O and Mg O nanoparticles. With the increase in synthesis temperature, the yield decreased, C content increased, H content decreased, N content remained the same basically, and BET surface area increased. The P adsorption of Ca–Mg/biochar could be accelerated by nano-Ca O and nano-Mg O particles and reached equilibrium after 360 min.The process was endothermic, spontaneous, and showed an increase in the disorder of the solid–liquid interface. Moreover, it could be fitted by the Freundlich model. The maximum P adsorption amounts were 294.22, 315.33, and 326.63 mg/g. The P adsorption selectivity of Ca–Mg/biochar could not be significantly influenced by the typical p H level of biogas fermentation liquid. The nano-Ca O and nano-Mg O particles of Ca–Mg/biochar could reduce the negative interaction effects of coexisting ions. The P releasing amounts of postsorption Ca–Mg/biochar were in the order of Ca–Mg/B600 > Ca–Mg/B450 > Ca–Mg/B300. Results revealed that postsorption Ca–Mg/biochar can continually release P and is more suitable for an acid environment.Ci Fang Tao Zhang Ping Li Rongfeng Jiang Shubiao Wu Haiyu Nie Yingcai Wang 2015Journal of Environmental Sciences2015,27,3:21
2Comparison of Headspace Solid-Phase Microextraction with Simultaneous Steam Distillation Extraction for the Analysis of the Volatile Constituents in Chinese Apricot显示文摘Volatile constituents in fully mature fruits of apricot (Prunus armeniaca L.) cultivar Xinshiji were extracted using headspace solid-phase microextraction (HS-SPME) and simultaneous steam distillation extraction (SSDE) and then analyzed using capillary gas chromatography and gas chromatography-mass spectrometry. A total of 70 components were identified by HS- SPME, including 20 esters, 19 hydrocarbons, 5 alcohols, 5 ketones, 4 acids, 4 lactones, 3 aldehydes, and 10 miscellaneous components, with the esters being the dominant constituent. On the basis of the odor unit values, it is believed that the following compounds probably contributed to the fresh apricot odor: hexyl acetate, β-ionone, butyl acetate, (E)-2-hexenal, linalool, limonene, γ-decalactone, and hexanal. A total of 49 components were also detected by SSDE, including 13 hydrocarbons, 9 alcohols, 7 aldehydes, 9 esters, 4 ketones, 4 lactones, 2 acids, and 1 miscellaneous component, of which the monoterpene alcohols were the dominant constituents. It could be judged from the odor unit values that the following compounds were the major contributors to boiled apricot aroma: β-ionone, linalool, hexyl acetate, γ-dodecalactone, γ- decalactone, (E)-2-hexenal, hexanal, γ-octalactone, phenylacetaldehyde, butyl acetate, limonene, α-terpineol, and δ-decalactone. The results show that HS-SPME is a simple, rapid, and solvent-free method, which is an alternative to the classical SSDE.CHEN Mei-xia CHEN Xue-sen WANG Xin-guo CI Zhi-juan LIU Xiao-li HE Tian-ming ZHANG Li-jie 2006Agricultural Sciences in China2006,5,11:20
3Combined subfascial endoscopic perforator surgery and endovenous laser treatment without impact on the great saphenous vein for management of lower-extremity varicose veins显示文摘GAN Shu-jie QIAN Shui-xian ZHANG Ci MAO Jie-qi LI Ke TANG Jing-dong 2013Chinese Medical Journal2013,,3:18
4Functional traits of tree species with phylogenetic signal co-vary with environmental niches in two large forest dynamics plots显示文摘Aims While using phylogenetic and functional approaches to test the mechanisms of community assembly,functional traits often act as the proxy of niches.However,there is little detailed knowledge regarding the correlation between functional traits of tree species and their niches in local communities.We suggest that the co-varying correlation between functional traits and niches should be the premise for using phylogenetic and functional approaches to test mechanisms of community assembly.Using functional traits,phylogenetic and environmental data,this study aims to answer the questions:(i)within local communities,do functional traits of co-occurring species covary with their environmental niches at the species level?and(ii)what is the key ecological process underlying community assembly in Xishuangbanna and Ailaoshan forest dynamic plots(FDPs)?Methods We measured seven functional traits of 229 and 36 common species in Xishuangbanna and Ailaoshan FDPs in tropical and subtropical China,respectively.We also quantified the environmental niches for these species based on conditional probability.We then analyzed the correlations between functional traits and environmental niches using phylogenetic independent contrasts.After examining phylogenetic signals of functional traits using Pagel’sλ,we quantified the phylogenetic and functional dispersion along environmental gradients within local tree communities.Important Findings For target species,functional traits do co-vary with environmental niches at the species level in both of the FDPs,supporting that functional traits can be used as a proxy for local-scale environmental niches.Functional traits show significant phylogenetic signals in both of the FDPs.We found that the phylogenetic and functional dispersion were significantly clustered along topographical gradients in the Ailaoshan FDP but overdispersion in the Xishuangbanna FDP.These patterns of phylogenetic and functional dispersion suggest that environmental filtering plays a key role in structuring local tree assemblages in Ailaoshan FDP,while competition exclusion plays a key role in Xishuangbanna FDP.Jie Yang Xiuqin Ci Mengmeng Lu Guocheng Zhang Min Cao Jie Li Luxiang Lin 2014Journal of Plant Ecology2014,7,2:16
5COVID-19: Challenges to GIS with Big Data显示文摘The outbreak of the 2019 novel coronavirus disease(COVID-19)has caused more than 100,000 people infected and thousands of deaths.Currently,the number of infections and deaths is still increasing rapidly.COVID-19 seriously threatens human health,production,life,social functioning and international relations.In the fight against COVID-19,Geographic Information Systems(GIS)and big data technologies have played an important role in many aspects,including the rapid aggregation of multi-source big data,rapid visualization of epidemic information,spatial tracking of confirmed cases,prediction of regional transmission,spatial segmentation of the epidemic risk and prevention level,balancing and management of the supply and demand of material resources,and socialemotional guidance and panic elimination,which provided solid spatial information support for decision-making,measures formulation,and effectiveness assessment of COVID-19 prevention and control.GIS has developed and matured relatively quickly and has a complete technological route for data preparation,platform construction,model construction,and map production.However,for the struggle against the widespread epidemic,the main challenge is finding strategies to adjust traditional technical methods and improve speed and accuracy of information provision for social management.At the data level,in the era of big data,data no longer come mainly from the government but are gathered from more diverse enterprises.As a result,the use of GIS faces difficulties in data acquisition and the integration of heterogeneous data,which requires governments,businesses,and academic institutions to jointly promote the formulation of relevant policies.At the technical level,spatial analysis methods for big data are in the ascendancy.Currently and for a long time in the future,the development of GIS should be strengthened to form a data-driven system for rapid knowledge acquisition,which signifies ts that GIS should be used to reinforce the social operation parameterization of models and methods,especially when providing support for social management.Chenghu Zhou Fenzhen Su Tao Pei An Zhang Yunyan Du Bin Luo Zhidong Cao Juanle Wang Wen Yuan Yunqiang Zhu Ci Song Jie Chen Jun Xu Fujia Li Ting Ma Lili Jiang Fengqin Yan Jiawei Yi Yunfeng Hu Yilan Liao Han Xiao 2020Geography and Sustainability2020,1,1:13
6Walnut-inspired microsized porous silicon/graphene core-shell composites for high-performance lithium-ion battery anodes显示文摘Wei Zhai Qing Ai Lina Chen Shiyuan Wei Deping Li Lin Zhang Pengchao Si Jinkui Feng Lijie Ci 2017Nano Research2017,10,12:12
7Cortical plasticity and nerve regeneration after peripheral nerve injury显示文摘With the development of neuroscience, substantial advances have been achieved in peripheral nerve regeneration over the past decades. However, peripheral nerve injury remains a critical public health problem because of the subsequent impairment or absence of sensorimotor function. Uncomfortable complications of peripheral nerve injury, such as chronic pain, can also cause problems for families and society. A number of studies have demonstrated that the proper functioning of the nervous system depends not only on a complete connection from the central nervous system to the surrounding targets at an anatomical level, but also on the continuous bilateral communication between the two. After peripheral nerve injury, the interruption of afferent and efferent signals can cause complex pathophysiological changes, including neurochemical alterations, modifications in the adaptability of excitatory and inhibitory neurons, and the reorganization of somatosensory and motor regions. This review discusses the close relationship between the cerebral cortex and peripheral nerves. We also focus on common therapies for peripheral nerve injury and summarize their potential mechanisms in relation to cortical plasticity. It has been suggested that cortical plasticity may be important for improving functional recovery after peripheral nerve damage. Further understanding of the potential common mechanisms between cortical reorganization and nerve injury will help to elucidate the pathophysiological processes of nerve injury, and may allow for the reduction of adverse consequences during peripheral nerve injury recovery. We also review the role that regulating reorganization mechanisms plays in functional recovery, and conclude with a suggestion to target cortical plasticity along with therapeutic interventions to promote peripheral nerve injury recovery.Ci Li Song-Yang Liu Wei Pi Pei-Xun Zhang 2021Neural Regeneration Research2021,16,8:12
8Genetic characterization and linkage disequilibrium mapping of resistance to gray leaf spot in maize(Zea mays L.)显示文摘Gray leaf spot(GLS),caused by Cercospora zeae-maydis,is an important foliar disease of maize(Zea mays L.)worldwide,resistance to which is controlled by multiple quantitative trait loci(QTL).To gain insights into the genetic architecture underlying the resistance to this disease,an association mapping population consisting of 161 inbred lines was evaluated for resistance to GLS in a plant pathology nursery at Shenyang in 2010 and 2011.Subsequently,a genome-wide association study,using 41,101 single-nucleotide polymorphisms(SNPs),identified 51 SNPs significantly(P<0.001)associated with GLS resistance,which could be converted into 31 QTL.In addition,three candidate genes related to plant defense were identified,including nucleotidebinding-site/leucine-rich repeat,receptor-like kinase genes similar to those involved in basal defense.Two genic SNPs,PZE-103142893 and PZE-109119001,associated with GLS resistance in chromosome bins 3.07 and 9.07,can be used for marker-assisted selection(MAS)of GLS resistance.These results provide an important resource for developing molecular markers closely linked with the target trait,enhancing breeding efficiency.Liyu Shi Xiangling Lv Jianfeng Weng Hanyong Zhu Changlin Liu Zhuanfang Hao Yu Zhou Degui Zhang Mingshun Li Xiaoke Ci Xinhai Li Shihuang Zhang 2014The Crop Journal2014,2,Z1:9
9Mercury in leaf litter in typical suburban and urban broadleaf forests in China显示文摘To study the role of leaf litter in the mercury (Hg) cycle in suburban broadleaf forests and the distribution of Hg in urban forests, we collected leaf litter and soil from suburban evergreen and deciduous broadleaf forests and from urban forests in Beijing. The Hg concentrations in leaf litter from the suburban forests varied from 8.3 to 205.0 ng/g, with an average (avg) of (49.7 ± 36.9) ng/g. The average Hg concentration in evergreen broadleaf forest leaf litter (50.8 ± 39.4) ng/g was higher than that in deciduous broadleaf forest leaf litter (25.8 ± 10.1) ng/g. The estimated Hg fluxes of leaf litter in suburban evergreen and deciduous broadleaf forests were 179.0 and 83.7 mg/(ha·yr), respectively. The Hg concentration in organic horizons (O horizons) ((263.1 ± 237.2) ng/g) was higher than that in eluvial horizons (A horizons) ((83.9 ± 52.0) ng/g). These results indicated that leaf litterfall plays an important role in transporting atmospheric mercury to soil in suburban forests. For urban forests in Beijing, the Hg concentrations in leaf litter ranged from 8.8-119.0 (avg 28.1 ± 16.6) ng/g, with higher concentrations at urban sites than at suburban sites for each tree. The Hg concentrations in surface soil in Beijing were 32.0-25300.0 ng/g and increased from suburban sites to urban sites, with the highest value from Jingshan (JS) Park at the centre of Beijing. Therefore, the distribution of Hg in Beijing urban forests appeared to be strongly influenced by anthropogenic activities.Zhenchuan Niu Xiaoshan Zhang Zhangwei Wang Zhijia Ci 2011Journal of Environmental Sciences2011,23,12:9
10Response and adaptation to the accumulation and distribution of photosynthetic product in peanut under salt stress显示文摘To clarify the response and adaptability of peanut under salt stress,Huayu 25 was used as the material,and non-salt stress(CK),0.15% salt stress(S1),and 0.3% salt stress(S2) were applied as three treatments.The study analysed the effects of salt stress on photosynthetic characteristics,photosynthetic substances accumulation and distribution as well as the ecological adaptability of peanuts.The results showed that net photosynthetic rate(Pn),SPAD value,leaf area,and peanut yield were reduced under salt stress.Pn in CK was 13.71 and 28.72% higher than that in S1 and S2 at the 50 th day after planting,respectively.At the same growth period,the SPAD value among treatments was ranked as follows: CK>S1>S2.The 100-pod mass,100-kernel mass,kernel rate to pod,and pod mass per plant were reduced under salt stress,and the trend was CK>S1>S2.The distribution proportion of dry matter in different organs of peanut plant was changed to adapt to such stress.Roots under salt stress intensively distributed in a 0-40 cm soil layer for salt resistance.Dry mass proportion in stems and pods increased during the vegetative stage and early period of reproductive stage,respectively.The maximum growth rates of the pod volume,pod dry weight,and seed kernel dry weight all declined,and the pod and kernel volume at harvest were reduced,improving the seed plumpness under salt stress.This finding could be useful in growing peanut in saline soil.ZHANG Guan-chu DAI Liang-xiang DING Hong CI Dun-wei NING Tang-yuan YANG Ji-shun ZHAO Xin-hua YU Hai-qiu ZHANG Zhi-meng 2020Journal of Integrative Agriculture2020,19,3:7
11Synthesis of magnetic polyphosphazene-Ag composite particles as surface enhanced Raman spectroscopy substrates for the detection of melamine显示文摘Magnetic polyphosphazene(MPZS) particles coated by Ag nanoparticles(MPZS-Ag) have been developed as surface enhanced Raman spectroscopy(SERS) substrates for sensitive detection of melamine in aqueous solutions and milk samples.5,5’-Dithiobis-(2-nitrobenzoic acid)(DTNB) was used as model analyte to test the SERS activity of the MPZS-Ag particles.The prepared MPZS-Ag particles possess both magnetic responsiveness and excellent SERS properties.SERS detection of different concentrations of melamine aqueous solutions and spiked milk samples were performed by the MPZS-Ag particles.The limit of detection(LOD) of the melamine in aqueous solutions was 10^-7 mol/L(0.0126 mg/L) and 0.6 mg/L in real milk samples using the MPZS-Ag particles as SERS substrates.The LOD of the melamine are much lower than the safety values of Food and Drug Administration and Codex Alimentarius Commission.These results indicate that the MPZS-Ag particles have promising application prospect for SERS analysis in food safety fields.Ci Huang Feifei Lu Ke Xu Guanjun Ding Lijun You Jiabin Wang Qiqing Zhang 2019Chinese Chemical Letters2019,30,12:6
12Cardiac arrhythmias and cardiac arrest related to mushroom poisoning: A case report显示文摘BACKGROUND Mushroom exposure is a global health issue.The manifestations of mushroom poisoning (MP) may vary.Some species have been reported as rhabdomyolytic,hallucinogenic,or gastrointestinal poisons.Critical or even fatal MPs are mostly attributable to Amanita phalloides,with the development of severe liver or renal failure.Myocardial injury and even cases mimicking ST-segment elevation myocardial infarction (STEMI) have been previously reported,while cardiac arrhythmia or cardiac arrest is not commonly seen.CASE SUMMARY We report a 68-year-old woman with MP who suffered from delirium,seizure,long QT syndrome on electrocardiogram (ECG),severe cardiac arrhythmias of multiple origins,and cardiac arrest.She was intubated and put on blood perfusion.Her kidney and liver functions were intact;creatine kinase-MB was mildly elevated,and then fell within normal range during her hospital stay.We sent the mushrooms she left for translation elongation factor subunit 1α,ribosomal RNA gene sequence,and internal transcribed spacer sequence analyses.There were four kinds of mushrooms identified,two of which were found to be toxic.CONCLUSION This is the first time that we found cardiac toxicity caused by Panaeolus subbalteatus and Conocybe lactea,which were believed to be toxic to the liver,kidney,and brain.We suggest that intensive monitoring and ECG follow-up are essential to diagnose prolonged QT interval and different forms of tachycardia in MP patients,even without the development of severe liver or renal failure.The mechanisms need to be further investigated and clarified based on animal experiments and molecular signal pathways.Shu Li Qing-Bian Ma Ci Tian Hong-Xia Ge Yang Liang Zhi-Guo Guo Cheng-Duo Zhang Bei Yao Jia-Ning Geng Fran Riley 2019World Journal of Clinical Cases2019,7,16:4
13Security in edge-assisted Internet of Things:challenges and solutions显示文摘The flourish of 5th generation wireless systems(5G)network has brought numerous benefits to the Internet of Things(IoT)with universal connectivity,improved data rate,and decreased latency.The development of IoT extends the computation-intensive applications from centralized servers to the edge of the network,promoting the paradigm of edge computing.Edge computing brings great assistance to IoT architecture by efficiently accomplishing tasks with lower latency,less energy consumption and reduced network bandwidth.Edge-assisted IoT emerges to provide location-aware services and offload computational tasks to edge nodes near the IoT devices.However,a series of security challenges still exist in edge-assisted IoT owing to the inherent vulnerabilities of edge nodes and sensitive nature of the collected data.Among the emerging and existing security schemes in IoT applications,security and energy consumption are two overriding yet conflicting requirements.The tradeoff between security and energy is critical to the sustainability of the IoT ecosystem but still lacks sufficient discussion.In this article,we investigate the security challenges in edge-assisted IoT and how the constraints in energy consumption can affect the design of security schemes.Specifically,we firstly present the architecture of edge-assisted IoT and its unique characteristics.Secondly,we identify the security threats in the edge-assisted IoT applications and the security-energy tradeoff during implementation.Thirdly,in a case study of distributed denial of service(DDoS)and malware injection attack,we propose a preliminary solution to address the conflict between security and energy requirements.Finally,we discuss some open issues and identify future research directions for security and energy efficiency in edge-assisted IoT.Shuaiqi SHEN Kuan ZHANG Yi ZHOU Song CI 2020Science China(Information Sciences)2020,63,12:4
14Simulation study on heat-affected zone of high-strain X80 pipeline steel显示文摘The microstructure evolution and impact-toughness variation of heat-affected zone(HAZ)in X80 highstrain pipeline steel were investigated via a welding thermal-simulation technique,Charpy impact tests,and scanning electron microscopy observations under different welding heat inputs and peak temperatures.The results indicate that when heat input was between 17 and 25kJ·cm^(-1),the coarse-grained heat-affected zone showed improved impact toughness.When the heat input was increased further,the martensite-austenite(M-A)islands transformed from fine lath into a massive block.Therefore,impact toughness was substantially reduced.When the heat input was 20kJ·cm^(-1) and the peak temperature of the first thermal cycle was between 900 and 1300°C,a higher impact toughness was obtained.When heat input was 20kJ·cm^(-1) and the peak temperature of the first thermal cycle was 1300°C,the impact toughness value at the second peak temperature of 900°C was higher than that at the second peak temperature of 800°C because of grain refining and uniformly dispersed M-A constituents in the matrix of bainite.Ying Ci Zhan-zhan Zhang 2017Journal of Iron and Steel Research(International)2017,24,9:4
15Contrasting effects of space and environment on functional and phylogenetic dissimilarity in a tropical forest显示文摘Aims The evolutionary history and functional traits of species can illumi-nate ecological processes supporting coexistence in diverse forest communities.However,little has been done in decoupling the rela-tive importance of these mechanisms on the turnover of phylogenetic and functional characteristics across life stages and spatial scales.Therefore,this study aims to estimate the contribution of environment and dispersal on the turnover of phylogenetic and functional diversity across life stages and spatial scales,in order to build a coherent pic-ture of the processes responsible for species coexistence.Methods We conducted the study in Xishuangbanna Forest Dynamics Plot in Yunnan Province,southwest China.We used four different spatial point process models to estimate the relative importance of disper-sal limitation and environmental filtering.The functional traits and phylogenetic relationships of all individual trees were incorporated in the analyses to generate measures of dissimilarity in terms of pair-wise and nearest-neighbor phylogenetic and functional characteris-tics across life stages and spatial scales.Important Findings We found non-random patterns of phylogenetic and functional turnover across life stages and spatial scales.Environmental filtering structured pairwise phylogenetic and functional beta diversity across spatial scales,while dispersal limitation alone,and in combination with environment filtering,shaped nearest neighbor phylogenetic and functional beta diversity.The relative importance of dispersal limitation and environmental filtering appeared to change with life stage but not with spatial scale.Our findings suggest that phylogenetic and functional beta diversity help to reveal the ecological processes responsible for evolu-tionary and functional assembly and highlight the importance of using a range of different metrics to gain full insights into these processes.Mengesha Asefa Calum Brown Min Cao Guocheng Zhang Xiuqin Ci Liqing Sha Jie Li Luxiang Lin Jie Yang 2019Journal of Plant Ecology2019,12,2:3
166-inch uniform vertically-oriented graphene on soda-lime glass for photothermal applications显示文摘Haina Ci Huaying Ren Yue Qi Xudong Chen Zhaolong Chen Jincan Zhang Yanfeng Zhang Zhongfan Liu 2018Nano Research2018,11,6:3
17Adaptive Control of MIMO Mechanical Systems with Unknown Actuator Nonlinearities Based on the Nussbaum Gain Approach显示文摘This paper investigates MIMO mechanical systems with unknown actuator nonlinearities. A novel Nussbaum analysis tool for MIMO systems is established such that unknown time-varying control coefficients are tackled. In contrast to existing literatures on continuous-time systems, the newly-developed Nussbaum tool focuses on extending the traditional Nussbaum result from one dimensional case to the multiple one. Specifically,not only the multiple unknown input coefficients are extended to the time-varying, but also the limitation of the prior knowledge of coefficients' upper and lower bounds is removed. Furthermore,an adaptive robust controller associated with the proposed tool is presented. The asymptotic tracking of MIMO mechanical systems is guaranteed with the help of the Lyapunov Theorem. Finally,a simulation example is provided to examine the validity of the proposed scheme.Ci Chen Zhi Liu Yun Zhang C.L.Philip Chen Shengli Xie 2016IEEE/CAA Journal of Automatica Sinica2016,3,1:3
18Insights into the formation of secondary organic carbon in the summertime in urban Shanghai显示文摘To investigate formation mechanisms of secondary organic carbon(SOC) in Eastern China,measurements were conducted in an urban site in Shanghai in the summer of 2015. A period of high O_3 concentrations(daily peak > 120 ppb) was observed, during which daily maximum SOC concentrations exceeding 9.0 μg/(C·m^3). Diurnal variations of SOC concentration and SOC/organic carbon(OC) ratio exhibited both daytime and nighttime peaks. The SOC concentrations correlated well with O_x(= O_3+ NO_2) and relative humidity in the daytime and nighttime, respectively, suggesting that secondary organic aerosol formation in Shanghai is driven by both photochemical production and aqueous phase reactions. Single particle mass spectrometry was used to examine the formation pathways of SOC. Along with the daytime increase of SOC, the number fraction of elemental carbon(EC) particles coated with OC quickly increased from 38.1% to 61.9% in the size range of 250–2000 nm, which was likely due to gas-to-particle partitioning of photochemically generated semi-volatile organic compounds onto EC particles. In the nighttime, particles rich in OC components were highly hygroscopic, and number fraction of these particles correlated well with relative humidity and SOC/OC nocturnal peaks. Meanwhile, as an aqueous-phase SOC tracer, particles that contained oxalate-Fe(III) complex also peaked at night. These observations suggested that aqueous-phase processes had an important contribution to the SOC nighttime formation. The influence of aerosol acidity on SOC formation was studied by both bulk and single particle level measurements, suggesting that the aqueous-phase formation of SOC was enhanced by particle acidity.Ci Zhang Xiaohui Lu Jinghao Zhai Hong Chen Xin Yang Qi Zhang Qianbiao Zhao Qingyan Fu Fei Sha Jing Jin 2018Journal of Environmental Sciences2018,30,10:3
19Demographic history of the Tibetan antelope Pantholops hodgsoni(chiru)显示文摘The Tibetan antelope(chiru,Pantholops hodgsoni),a heavily poached species and symbol of the QinghaiTibetan Plateau(QTP),is noted worldwide for its special calving migration.This species originated in the early Quaternary and it is interesting to know how the following climatic oscillations affected its demographic dynamics in the climate-sensitive QTP.In this study,we analyzed the mitochondrial D-loop region from 312 individuals sampled in all of the six major populations.We found high rates of gene flow and little genetic differentiation between populations,suggesting that the calving migration may have homogenized the genetic pool of this species.Both mismatch distribution analyses and coalescent simulations suggested that this species experienced a demographic expansion approximately 600-200 Kyr following the retreat of the large glaciers developed in the QTP at 800-600 Kyr,rather than at the end of the last glacial age,as previously suggested,based on a limited sample size.In addition,we found evidence of a chiru population decrease probably related to the human settings at the QTP during the middle Holocene.Yu-Rong DU Song-Chang GUO Zhao-Feng WANG Hai-Xing CI Zhen-Yuan CAI Qian ZHANG Jian-Ping SU Jian-Quan LIU 2010Journal of Systematics and Evolution2010,48,6:3
20Artificial woodland degradation in semi-arid agro-pastoral transitional area: conceptual model and status assessment显示文摘种树在中国的干旱、半干旱的区域为 desertificationcontrol 被用作划算的措施之一。然而,树林降级在这些区域正在成为一个不可避免的问题。在这篇论文,一个典型的县, Ejin Holo 县,内部蒙古,中国为它对人工的树林的评价被选择降级。为树林降级的一个概念的模型作为湿度指数基于现场取样调查,和 基于fourmodel 的指示物是描出的品质上(嗨),植被索引( NDVI ),土壤类形(圣)和土壤侵蚀模量(他们)外面被屏蔽并且在这半干旱的agro牧剧为人工的树林降级评价使用了到一个官方补给底的方法过渡区域。所有指示物层被覆盖,沙漠化评定了为每指示物与相等的重量使用简化方程。评价结果在 336 显示出那。全部的树林区域的 09 km^2, 311.35 km^2woodland 在降级,和区域下面因为细微、中等、严重降级分别地是 78.97,119.73 和 112.65 km^2。它那么被建议注意应该在树林改进和植物种类选择上被给予,特别灌木种类,在在类似的区域的植被前。YANG Xiao-hui CI Long-jun ZHANG Ke-bin 2006Journal of Forestry Research2006,17,3:3
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