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| 1 | Biomass carbon stocks and their changes in northern China's grasslands during 1982-2006显示文摘Grassland covers approximately one-third of the area of China and plays an important role in the global terrestrial carbon(C) cycle.However,little is known about biomass C stocks and dynamics in these grasslands.During 2001-2005,we conducted five consecutive field sampling campaigns to investigate above-and below-ground biomass for northern China's grasslands.Using measurements obtained from 341 sampling sites,together with a NDVI(normalized difference vegetation index) time series dataset over 1982-2006,we examined changes in biomass C stock during the past 25 years.Our results showed that biomass C stock in northern China's grasslands was estimated at 557.5 Tg C(1 Tg=1012 g),with a mean density of 39.5 g C m-2 for above-ground biomass and 244.6 g C m-2 for below-ground biomass.An increasing rate of 0.2 Tg C yr-1 has been observed over the past 25 years,but grassland biomass has not experienced a significant change since the late 1980s.Seasonal rainfall(January-July) was the dominant factor driving temporal dynamics in biomass C stock;however,the responses of grassland biomass to climate variables differed among various grassland types.Biomass in arid grasslands(i.e.,desert steppe and typical steppe) was significantly associated with precipitation,while biomass in humid grasslands(i.e.,alpine meadow) was positively correlated with mean January-July temperatures.These results suggest that different grassland ecosystems in China may show diverse responses to future climate changes. | Anwar MOHAMMAT | 2010 | Science China(Life Sciences)2010，53，7： | 60 |
| 2 | 沪、深两市大宗交易制度演进及市场交易特征显示文摘本文对我国沪深两市的大宗交易制度演进过程作了详细梳理 ,并根据对我国大宗交易市场数据的分析 ,总结了沪深两市大宗交易呈现的特征。在文章最后一部分 ,针对我国大宗交易制度应当在交易方式、交易时间、交易价格限制 ,以及大宗交易制度的其它方面提出了放宽条款限制的建议。 | 朱玺 | 2004 | 财经科学2004，，2： | 19 |
| 3 | RAPD analysis of wild stock of penaeid shrimp (Penaeus chinensis )in Chinese coastal waters of the Huanghai Sea and coastal waters of the Bohai Sea显示文摘Genetic diversity of 32 individuals of P. chinensis in the Chinese coastal waters of the Huanghai and Bobal Seas was detected by RAPD technique. Twenty decamer primers of OPI were used for DNA amplification for each individual. The results showed that: Seventeen primers obtained reproducible fingerprints, and the bands were clear. Thirty--nine of 106 loci detected were polymorphic, amounting to 36. 8 %. Mean genetic distance was 0. 094 1 0. 020 6; 68 markers (63. 2 % of the total) showed stable homogeneity in all of the 32 individuals. | Liu Ping Kong Jie Shi Tuo Zhuang Zhimeng Deng Jingyao (l. Huanghai Sea Fisheries Research institute , Chinese Academy of Fishery Sciences, Qingdao 266071, China) | 2000 | Acta Oceanologica Sinica2000，19，1： | 18 |
| 4 | Forecasting Method of Stock Market Volatility in Time Series Data Based on Mixed Model of ARIMA and XGBoost显示文摘Stock price forecasting is an important issue and interesting topic in financial markets.Because reasonable and accurate forecasts have the potential to generate high economic benefits,many researchers have been involved in the study of stock price forecasts.In this paper,the DWT-ARIMAGSXGB hybrid model is proposed.Firstly,the discrete wavelet transform is used to split the data set into approximation and error parts.Then the ARIMA(0,1,1),ARIMA(1,1,0),ARIMA(2,1,1)and ARIMA(3,1,0)models respectively process approximate partial data and the improved xgboost model(GSXGB)handles error partial data.Finally,the prediction results are combined using wavelet reconstruction.According to the experimental comparison of 10 stock data sets,it is found that the errors of DWT-ARIMA-GSXGB model are less than the four prediction models of ARIMA,XGBoost,GSXGB and DWT-ARIMA-XGBoost.The simulation results show that the DWT-ARIMA-GSXGB stock price prediction model has good approximation ability and generalization ability,and can fit the stock index opening price well.And the proposed model is considered to greatly improve the predictive performance of a single ARIMA model or a single XGBoost model in predicting stock prices. | Yan Wang Yuankai Guo | 2020 | China Communications2020，17，3： | 15 |
| 5 | Comparison of carbon sequestration efficiency in soil aggregates between upland and paddy soils in a red soil region of China显示文摘There is limited information on carbon sequestration efficiency(CSE)of soil aggregates in upland and paddy soils under long-term fertilization regimes.In a red soil region of southern China,an upland soil experiment started in 1986 and a paddy soil experiment commenced in 1981.These experiments were conducted using different fertilization treatments.After 30 years,soil organic carbon(SOC)content and stock of different aggregate components were analyzed.The results showed that the SOC contents and stocks in upland soil were lower than in paddy soil.In both upland and paddy soils,the SOC contents and stocks of all aggregate components in NPKM(combined treatment with chemical nitrogen(N),phosphorus(P),potassium(K)fertilizers and manure)were the highest among all treatments.Compared with CK(no fertilizer),SOC content of all aggregate components in NPKM was increased by 13.21–63.11%and 19.13–73.33%in upland and paddy soils,respectively.Meanwhile,the change rates in SOC stock of all aggregate components in upland soil were lower than in paddy soil,although the change rate of SOC stock of all aggregate components in NPKM was higher than in other treatments.Furthermore,a linear equation could fit the relationships between carbon(C)input and change rate of SOC stock(P<0.05).Results indicated that the sum of CSE from all aggregate components in upland soil(16.02%)was higher than that of paddy soil(15.12%)in the same climatic condition and from the same parent material.However,the CSEs from all aggregates were higher than that of bulk soil,although the result from bulk soil also showed that the CSE of upland soil was higher than that of paddy soil. | LIU Kai-lou HUANG Jing LI Da-ming YU Xi-chu YE Hui-cai HU Hui-wen HU Zhi-hua HUANG Qing-hai ZHANG Hui-min | 2019 | Journal of Integrative Agriculture2019，18，6： | 12 |
| 6 | 运用SS3评估东太平洋大眼金枪鱼(Thunnus obesus)资源--复杂模型和简化模型的比较显示文摘大眼金枪鱼(Thunnus obesus)是东太平洋最重要的商业性金枪鱼鱼种,其资源评估采用的是结构复杂的Stock Synthesis 3模型(SS3)。模型简化是提高资源评估效率的必要手段,但对大眼金枪鱼简化模型的效果尚未开展研究。本研究尝试从渔业数据结构的角度,将SS3复杂模型的23个渔业简化为仅含围网和延绳钓2个渔业,从而比较简化模型的评估能力。结果显示,简化模型能较为准确地描述大眼金枪鱼补充量、亲体量、捕捞死亡系数等主要时间序列的历史动态变化,对传统生物学参考点FMSY的估计也较为准确,且受陡度和自然死亡系数的影响较小,但对其他参考点的估算误差较大。陡度参数对简化模型基于Kobe图判断资源状态的准确性有重要影响,陡度较低时,简化模型能较为准确地判断资源状态。研究表明,权衡模型的评估能力和降低模型结构的复杂性,是大眼金枪鱼资源评估今后需要重点研究的任务之一。此外,对模型简化的效果评价,与采用的生物学参考点和资源状况判断标准的选择有关。 | 朱江峰 | 2017 | 渔业科学进展2017，38，3： | 10 |
| 7 | Can media exposure improve stock price efficiency in China and why?显示文摘The media in China has undergone extensive commercialization to become more market-driven over the last 35 years. Based on a sample of over two million newspaper articles, this study investigates whether the media in China has an incremental impact on stock price efficiency. We find that: as media coverage of a firm increases,(1) its stock price synchronicity decreases;(2)the probability of informed trading of its stock increases; and(3) the extent to which its stock price deviates from random walk decreases. Our interregional analysis over thirty-one provinces/regions within China reveals that the effects of the media on decreasing stock price synchronicity, increasing the probability of informed trading, and reducing stock price deviation from random walk are stronger in regions of weaker institutional development.Our findings suggest that a market-driven media can play the role of compensating for the underdeveloped governance institutions in transitional economies such as China. | Jeong-Bon Kim Zhongbo Yu Hao Zhang | 2016 | China Journal of Accounting Research2016，，2： | 8 |
| 8 | Residue management induced changes in soil organic carbon and total nitrogen under different tillage practices in the North China Plain显示文摘Crop residue retention has been considered a practicable strategy to improve soil organic carbon(SOC)and total nitrogen(TN),but the effectiveness of residue retention might be different under varied tillage practices.To evaluate the effects of residue management on the distribution and stocks of SOC and TN under different tillage practices,a bifactorial experiment with three levels for tillage practices(no-tillage,rotary tillage,and conventional tillage)and two levels for residue managements(residue retention and residue removal)was conducted in the North China Plain(NCP).Results showed that after a short experimental duration(3–4 years),concentrations of SOC and TN in the 0–10 cm layer were higher under no-tillage than under conventional tillage,no matter whether crop residues were retained or not.Residue retention increased SOC and TN concentrations in the upper layers of soil to some degree for all tillage practices,as compared with residue removal,with the greatest increment of SOC concentration occurred in the 0–10 cm layer under rotary tillage,but in the 10–30 cm layer under conventional tillage.The stocks of SOC in the 0–50 cm depth increased from 49.89 Mg ha–1 with residue removal to 53.03 Mg ha–1 with residue retention.However,no-tillage did not increase SOC stock to a depth of 50 cm relative to conventional tillage,and increased only by 5.35%as compared with rotary tillage.Thus,residue retention may contribute more towards SOC sequestration than no-tillage.Furthermore,the combination between residue retention and no-tillage has the greatest advantage in enhancing SOC and TN in the NCP region. | PU Chao KAN Zheng-rong LIU Peng MA Shou-tian QI Jian-ying ZHAO Xin ZHANG Hai-lin | 2019 | Journal of Integrative Agriculture2019，18，6： | 8 |
| 9 | Religion and stock price crash risk:Evidence from China显示文摘This paper investigates whether religious traditions influence firm-specific crash risk in China.Using a sample of A-share listed firms from 2003 to 2013,we provide evidence that the more intense the religious environment,the lower the stock price crash risk,implying that religion plays an important role in Chinese corporate governance.Further,we find that(1) religion affects stock price crash risk by reducing earnings management and the management perk problem;(2) different religions have different effects,and Taoism,in particular,is unrelated to crash risk; and(3) the effects of religion are more pronounced with higher quality corporate governance and a stronger legal environment.Religion constrains the management agency problem,thus reducing stock price crash risk in China.Our paper enriches the literature on stock price crash risk and religion,and on new economic geography. | Wenfei Li Guilong Cai | 2016 | China Journal of Accounting Research2016，，3： | 7 |
| 10 | 联合促销与库存控制显示文摘研究多周期联合促销与库存控制问题,其中需求同时依赖促销和一个随机变量.在每一周期,决策者同时决定促销水平和订货量.利用Markov决策为该问题建模.对有限和无限周期问题,证明了最优策略是Base stock target promotion策略.对产能有限问题,最优策略是修正的Base stock target promotion策略.这说明当初始库存较低且产能较小时,减少促销水平;当初始库存水平较高时,不订货,增加促销力度.产能充足时,要增加促销水平,增加需求,提高利润. | 张菊亮 | 2009 | 系统工程理论与实践2009，29，2： | 7 |
| 11 | Dynamics of forest biomass carbon stocks from 1949 to 2008 in Henan Province,east-central China显示文摘We estimated forest biomass carbon storage and carbon density from 1949 to 2008 based on nine consecutive forest inventories in Henan Province,China.According to the definitions of the forest inventory,Henan forests were categorized into five groups: forest stands,economic forests,bamboo forests,open forests,and shrub forests.We estimated biomass carbon in forest stands for each inventory period by using the continuous biomass expansion factor method.We used the mean biomass density method to estimate carbon stocks in economic,bamboo,open and shrub forests.Over the 60-year period,total forest vegetation carbon storage increased from34.6 Tg(1 Tg = 1×10^(12)g) in 1949 to 80.4 Tg in 2008,a net vegetation carbon increase of 45.8 Tg.By stand type,increases were 39.8 Tg in forest stands,5.5 Tg in economic forests,0.6 Tg in bamboo forests,and-0.1 Tg in open forests combine shrub forests.Carbon storageincreased at an average annual rate of 0.8 Tg carbon over the study period.Carbon was mainly stored in young and middle-aged forests,which together accounted for 70–88%of the total forest carbon storage in different inventory periods.Broad-leaved forest was the main contributor to forest carbon sequestration.From 1998 to 2008,during implementation of national afforestation and reforestation programs,the carbon storage of planted forest increased sharply from 3.9 to 37.9 Tg.Our results show that with the growth of young planted forest,Henan Province forests realized large gains in carbon sequestration over a 60-year period that was characterized in part by a nation-wide tree planting program. | Yanfang Wang Ling Liu Zhouping Shangguan | 2018 | Journal of Forestry Research2018，29，2： | 5 |
| 12 | Alternative ventilation strategies in U.S.offices:Comprehensive assessment and sensitivity analysis of energy saving potential显示文摘Mature technologies exist to reduce the heating,ventilation,and air-conditioning(HVAC) energy associated with ventilation and use ventilation proactively to save energy.This study investigated the energy use impacts in U.S.office buildings of multiple alternative ventilation strategies that combined:economizing,demand controlled ventilation(DCV),supply air temperature reset(SR),and/or a doubled ventilation rate.We used energy simulations in a Monte Carlo analysis,sampling 17 building inputs and varying locations to match the climate zone distribution of the U.S.office stock.Results indicated the possibility for significant savings compared to a baseline that ventilated constantly at a minimum rate in both a small office type with a constant air volume(CAV) HVAC system and a medium office type with a variable air volume(VAV) system.In 95%of instances,HVAC source energy savings were 5-25%in the small-CAV office(median:11%) and 6-42%in the medium-VAV office(median:27%).In the small-CAV office,DCV typically saved the most energy,usually from heating,and heating degree days and occupant density were decisive influences.In the medium-VAV office,economizing and SR were most important,DCV usually only had minor impacts,and zone temperature setpoints,along with climate indicators,were the critical influences.Other than infiltration,envelope characteristics did not strongly influence energy impacts.The untapped primary energy savings of alternative ventilation strategies over the 74%of U.S.office floorspace reasonably represented by our modeling was estimated at 36 TWh per year,with an annual value of U.S.$ 1.25 billion. | Adams Rackes Michael S.Waring 侯恩哲 | 2017 | 建筑节能2017，45，5： | 5 |
| 13 | Flexible scheduling model of crude oil operations under crude supply disturbance显示文摘Today’s changeable market and resultant disturbance of crude oil supply require agile and flexible scheduling of crude oil operation. The objective of flexible scheduling is to keep stable crude oil op-eration and satisfy production demands under the circumstances of supply disturbance. In this paper, a new mixed integer non-linear programming (MINLP) formulation is set up for crude oil scheduling firstly, and then some heuristic rules worked out by some experts are proposed to linearize bilinear terms and prefix some binary variables in the MINLP model. These rules not only reduce the complexity of the MINLP model, but also can be used to solve the scheduling problems in various conditions. In case study, the new model with heuristic rules and the best models reported in the literature are com-pared and evaluated in three benchmark examples in the normal situation, and then three abnormal situations of supply delay are considered based on the new approach. The results of case study show that the new flexible approach can handle crude oil scheduling problems efficiently in both normal and abnormal conditions. | Ming Pan Yu Qian XiuXi Li | 2009 | Science China Chemistry2009，52，3： | 4 |
| 14 | Genome of a citrus rootstock and global DNA demethylation caused by heterografting显示文摘Grafting is an ancient technique used for plant propagation and improvement in horticultural crops for at least 1,500 years.Citrus plants,with a seed-to-seed cycle of 5–15 years,are among the fruit crops that were probably domesticated by grafting.Poncirus trifoliata,a widely used citrus rootstock,can promote early flowering,strengthen stress tolerance,and improve fruit quality via scion–rootstock interactions.Here,we report its genome assembly using PacBio sequencing.We obtained a final genome of 303 Mb with a contig N50 size of 1.17Mb and annotated 25,680 protein-coding genes.DNA methylome and transcriptome analyses indicated that the strong adaptability of P.trifoliata is likely attributable to its special epigenetic modification and expression pattern of resistance-related genes.Heterografting by using sweet orange as scion and P.trifoliata as rootstock and autografting using sweet orange as both scion and rootstock were performed to investigate the genetic effects of the rootstock.Single-base methylome analysis indicated that P.trifoliata as a rootstock caused DNA demethylation and a reduction in 24-nt small RNAs(sRNAs)in scions compared to the level observed with autografting,implying the involvement of sRNA-mediated graft-transmissible epigenetic modifications in citrus grafting.Taken together,the assembled genome for the citrus rootstock and the analysis of graft-induced epigenetic modifications provide global insights into the genetic effects of rootstock–scion interactions and grafting biology. | Yue Huang Yuantao Xu Xiaolin Jiang Huiwen Yu Huihui Jia Chunming Tan Gang Hu Yibo Hu Muhammad Junaid Rao Xiuxin Deng Qiang Xu | 2021 | Horticulture Research2021，8，1： | 4 |
| 15 | 荷兰观赏苗木的生产显示文摘文章介绍了荷兰在观赏苗木生产与培育方面的基本经验,如专业化的生产模式,多样化的观赏树木种类,严格的质量控制与监督、检测体系,完善的生产、管理与服务系统,以及高度重视创新等。同时,针对我国观赏苗木生产的现状提出几点建议。 | 张少杰 吴泽民 | 2003 | 中国城市林业2003，1，3： | 4 |
| 16 | Do institutional investors have superior stock selection ability in China?显示文摘This paper uses unique data on the shareholdings of both institutional and individual investors to directly investigate whether institutional investors have better stock selection ability than individual investors in China.Controlling for other factors,we find that institutional investors increase(decrease)their shareholdings in stocks that subsequently exhibit positive(negative)short-and long-term cumulative abnormal returns.In contrast individual investors decrease(increase)their shareholdings in stocks that subsequently exhibit positive(negative)short-and long-term cumulative abnormal returns.These findings indicate that institutional investors have superior stock selection ability in China. | Yihong Deng Yongxing Xu | 2011 | China Journal of Accounting Research2011，，3： | 3 |
| 17 | The chaotic behavior among the oil prices, expectation of investors and stock returns: TAR-TR-GARCH copula and TAR-TR-TGARCH copula显示文摘This paper has two aims. The first one is to investigate the existence of chaotic structures in the oil prices, expectations of investors and stock returns by combining the Lyapunov exponent and Kolmogorov entropy, and the second one is to analyze the dependence behavior of oil prices, expectations of investors and stock returns from January 02, 1990, to June06, 2017. Lyapunov exponents and Kolmogorov entropy determined that the oil price and the stock return series exhibited chaotic behavior. TAR-TR-GARCH and TAR-TR-TGARCH copula methods were applied to study the co-movement among the selected variables. The results showed significant evidence of nonlinear tail dependence between the volatility of the oil prices, the expectations of investors and the stock returns. Further, upper and lower tail dependence and comovement between the analyzed series could not be rejected. Moreover, the TAR-TR-GARCH and TAR-TR-TGARCH copula methods revealed that the volatility of oil price had crucial effects on the stock returns and on the expectations of investors in the long run. | Melike Bildirici | 2019 | Petroleum Science2019，16，1： | 3 |
| 18 | Aboveground biomass and carbon stock in the largest sacred grove of Manipur,Northeast India显示文摘Aboveground biomass and carbon stock in the largest sacred grove of Manipur was estimated for trees with diameter [10 cm at 1.37 m height.The aboveground biomass,carbon stock,tree density and basal area of the sacred grove ranged from 962.94 to 1130.79 Mg ha^(-1),481.47 to 565.40 Mg ha^(-1) C,1240 to 1320 stem ha^(-1) and79.43 to 90.64 m^2 ha^(-1),respectively.Trees in diameter class of 30–40 cm contributed the highest proportion of aboveground biomass(22.50–33.73%).The aboveground biomass and carbon stock in research area were higher than reported for many tropical and temperate forests,suggesting a role of spiritual forest conservation for carbon sink management. | Aahen Chanu Waikhom Arun Jyoti Nath P.S.Yadava | 2018 | Journal of Forestry Research2018，29，2： | 3 |
| 19 | 浅谈玉米单倍体的产生途径显示文摘玉米是重要的粮食作物。单倍体育种是提高选择效率和缩短育种周期的有效方法。通过分析各种玉米单倍体的产生途径,对其优缺点进行了比较。 | 马兰 | 2010 | 黑龙江农业科学2010，，8： | 3 |
| 20 | Interdependence between the stock market and the bond market in one country:evidence from the subprime crisis and the European debt crisis显示文摘Background:Once a global financial crisis breaks out,the interdependence between different financial markets suddenly increases and leads to a significant contagion.Methods:With 39 countries used as samples,this paper analyzes the interdependence between the stock market and the government bond market during the crisis periods.Results:It proves that the investor focuses more on the safety of their portfolio so there is neither a flight from quality nor a positive spillover during a crisis period.When one market is safer than the other market in the same country,a flight to quality occurs between the two markets;however,when the two markets in one country are both risky,negative spillover appears between these two markets.Conclusions:This means a flight to quality from the stock market to the short-term government bond will occur more frequently than will occur from the stock market to the long-term government bond markets.In addition,a flight to quality always emerges in developed markets,while negative spillovers take place in emerging markets and in the PIIGS countries(Portugal,Italy,Ireland,Greece,and Spain,referred to hereon as“PIIGS”)in the European Debt Crisis. | Ke Cheng Xiaoguang Yang | 2017 | Financial Innovation2017，3，1： | 3 |
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