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Journal of Geographical Sciences 2025年第1期35卷 65-87页

作者： CHEN Meng ZHOU Qiuwen PENG Dawei YAN Weihong School of Geography and Environmental Science Guizhou Normal University Huanjiang Observation and Research Station for Karst Ecosystem Guangxi Key Laboratory of Karst Ecological Processes and Services Institute of Subtropical Agriculture CAS University of Chinese Academy of Sciences Faculty of Geographical Science Beijing Normal University Forestry bureau of Shibing County

Terrestrial ecosystems heavily depend on vegetation,which responds to carbon dioxide （CO2） fertilization in hot and humid *** subtropical humid karst region is a hot and humid region;whether and to what extent CO2fertilization affects vegetation changes in such regions remains *** this study,we investigated the degree to which CO2fertilization influences vegetation changes,along with their spatial and temporal differences,in the subtropical humid karst region using time-lag effect analysis,a random forest model,and multiple regression *** showed that CO2fertilization plays an important role in vegetation changes,exhibiting clear spatial variations across different geomorphological zones,with its degree of influence ranging mainly between 11%and 25%.The highest contribution of CO2fertilization was observed in the karst basin and non-karstic region,whereas the lowest contribution was found in the karst plateau *** studies have primarily attributed vegetation changes in subtropical humid karst region to ecological engineering,leading to an overestimation of its contribution to these *** findings of this study enhance the understanding of the mechanism of vegetation changes in humid karst region and provide theoretical and practical insights for ecological and environmental protection in these regions.

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PRELIMINARY ANALYSIS OF MID-RANGE OSCILLATION OF TROPICAL MONSOON CIRCULATION IN SUMMER, 1979

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Acta Oceanologica Sinica 1983年第2期 205-212页

作者：周静亚张镡王景毅 Department of Geophysics Peking University Marine Forecasting Center national bureau of oceanography Beijing

In this paper, the mid-range oscillation with 30-45 days of the tropical monsoon circulation during May-August 1979 was discussed. It is found that there are low and high pressure index patterns for the tropical monsoon circulation in Northern Hemisphere. In the period of low index and the transitional period from low to high index, the group genesis and development of monsoon depressions, tropical cyclones over Arabian Sea and the Bengal Bay, typhoons over the South China Sea and Western Pacific Ocean are always successively observed from west to east. In this period, the rainfall over middle-India and eastern part of China usually *** can use the oscillation of the pressure value over equatorial area to describe the mid-range (30-45 days) oscillation of tropical monsoon circulation and its related circulation systems.

关键词： MID

Dust Aerosol Effects on Cirrus and Altocumulus Clouds in Northwest China

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Journal of Meteorological Research 2015年第5期29卷 793-805页

作者：王文彩盛立芳金宏春韩永清 Physical oceanography Laboratory Ocean University of China Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou University Shandong Provincial Meteorological bureau

Dust aerosol effects on the properties of cirrus and altocumulus cloud in Northwest China were studied for the period March-May 2007 by using the satellite data of Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations （CALIPSO）, Aqua, and CloudSat. Dusty clouds were defined as those mixed with dust aerosols or existing in dust aerosol conditions, while pure clouds were those in a dust-free environment. For dusty altocumulus clouds, the mean values of cloud optical depth （OPD）, cloud liquid water path （LWP）, cloud ice water path （IWP）, cloud effective particle radius （Re）, and cloud effective particle diameter （Dr） were 6.40, 40.23 g m-2, 100.70 g m-2, 8.76 μm, and 40.72 μm, respectively. For pure altocumulus clouds, the corresponding mean values were 9.28, 76.70 g m-2, 128.75 g m-2, 14.03 μm, and 48.92 μm, respectively. These results show a significant decrease of OPD, LWP, IWP, Re, and De of approximately 31%, 48%, 22%, 38%, and 17% because of the effects of dust aerosols. Moreover, the effects of dust aerosols on liquid-phase altocumulus clouds were greater than on ice-phase altocumulus clouds. Regarding dusty cirrus clouds, the mean values of OPD, IWP, and De were 5.11, 137.53 g in 2, and 60.44 μm, respectively. In contrast, the mean values were 6.69, 156.17 g m-2, and 66.63 μm, respectively, for pure cirrus clouds, with a 24% decrease in OPD, a 12% decrease in IWP, and a 9% decrease in De. These results indicate that dust aerosols can significantly change cloud properties, leading to a reduction of OPD, LWP, and effective particle size for both altocumulus and cirrus clouds in Northwest China.

关键词： dusty cloud aerosol-cloud interaction altocumulus cloud cirrus cloud

The impact of biotic and abiotic factors on the distribution of surface sediment dinoflagellate cyst assemblages on the Nanji Island in the East China Sea

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Acta Oceanologica Sinica 2019年第1期38卷 160-171页

作者： Han Gao Shengpao You Xiangdong Lei Yunpu Xiao Haifeng Gu Mengmeng Tong Ocean College Zhejiang University Nanji Marine Environment Monitoring Station Ministry of Natural Resources Pingyang County Marine and Fisheries bureau Third Institute of oceanography Ministry of Natural Resources

The dinoflagellate cyst assemblages on the Nanji Island in the East China Sea, are documented at the first time to construct a quantitative overview of the cyst bank from 2014 to 2015. Thirty-four morphotypes from six groups are identified and quantified at eight sampling sites around the island, including a high proportion of potentially toxigenic species(14%). Autotrophic dinocysts constitute 74% of the total cyst counts, which is relatively low(two to thirty-three per millilitre sediment) compared with previous studies in adjacent areas. Scrippsiella trochoidea and Protoperidinium avellana are the most abundant autotrophic and heterotrophic species, respectively. A multivariate analysis is performed to assess associations between dinocysts and abiotic or biotic *** among seasons is evident in the detrended correspondence analysis(DCA) ordination plot, while a spatial pattern is not clearly revealed despite heterogeneity of the hydrodynamic conditions between sampling sites. Soluble reactive phosphate, the ratio of nitrogen to phosphorus concentrations and Karenia mikimotoi bloom are the three factors significantly(P<0.05) related to surface sediment cyst assemblage defined by the canonical correspondence analysis(CCA), highlighting the importance of nutrient regime to a dinocyst distribution in this area. Although attempts to address the origin of HAB events in recent years using seed banks have failed, knowledge can be valuable for further investigation of dinocyst dynamics and potential toxin threats on the Nanji Island.

关键词： dinoflagellate cyst Nanji Island nutrients harmful algal blooms

Regenerative Cooling for Liquid Rocket Engines

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Journal of Thermal Science 1995年第1期4卷 54-58页

作者： Qi Feng(No.11 Institute of the national bureau of Astronautics) No.11 Institute of the national bureau of Astronautics China

Heat transfer in the thrust chamber is of great importance in the design of liquid propellant rocketengines. Regenerative cooling is an advanced method which can ensure not only the proper runningbut also higher performance of a rocket engine. The theoretical model is complicated, it relates to fluiddynamics, heat transfer, combustion, etc... In this papers a regenerative cooling model is *** such as radiation, heat transfer to environment, variable thermal properties and coking areincluded in the model. This model can be applied to all kinds of liquid propellant rocket engines aswell as similar constructions. The modularized computer code is completed in the work.

关键词： liquid propellant rocket engine regenerative cooling thrust chamber heat transfer hydrogen methane kerosene.

CLIMATIC CHARACTERISTICS OF TYPHOON PRECIPITATION OVER CHINA

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Journal of Tropical Meteorology 2008年第2期14卷 125-128页

作者：王咏梅任福民李维京王小玲 Yuncheng Weather bureau national Climate Center China Meteorological Administration

The spatio-temporal characteristics of typhoon precipitation over China are analyzed in this study. The results show that typhoon precipitation covers most of central-eastern China. Typhoon precipitation gradually decreases from the southeastern coastal regions to the northwestern mainland. The maximum annual typhoon precipitation exceeds 700 mm in central-eastern Taiwan and part of Hainan, while the minimum annual typhoon precipitation occurs in parts of Inner Mongolia, Shanxi, Shaanxi and Sichuan, with values less than 10 mm. Generally, typhoons produce precipitation over China during April - December with a peak in August. The annual typhoon precipitation time series for observation stations are examined for long-term trends. The results show that decreasing trends exist in most of the stations from 1957 to 2004 and are statistically significant in parts of Taiwan, Hainan, coastal Southeast China and southern Northeast China. The anomaly of typhoon precipitation mainly results from that of the general circulation over Asia and the Walker Cell circulation over the equatorial central and eastern Pacific. Typhoon torrential rain is one of the extreme rainfall events in the southeastern coastal regions and parts of central mainland. In these regions, torrential rains are mostly caused by typhoons.

关键词： typhoon precipitation long-term trends typhoon torrential rain

CASE ANALYSIS OF SEA LEVEL CIRCULATION FOR THE ATMOSPHERE OF LOW LATITUDES IN MID-SUMMER

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Acta Oceanologica Sinica 1985年第1期 35-41页

作者：张镡王景毅 Department of Geophysics Peking University Marine Environment Forecasting Center national bureau of oceanography Beijing

In the light of the sea level synoptic charts from July to August for 1975-1978, we obtained more observed records of low latitudes by using the analysed stream and temperature-moisture field (or so called energy field θe field and θse field), the main characteristics of these fields in the period of multi-typhoon genesis and of typhoon interval in the mid-summer are ***, it should be pointed out that the position of the typhoon genesis and the typhoon track are generally consistent with the low temperature-moisture region of the sea surface as well as with its tendency, so that a valuable information is obtained for the forecast of the typhoon track.

关键词： CASE ANALYSIS OF SEA LEVEL CIRCULATION FOR THE ATMOSPHERE OF LOW LATITUDES IN MID-SUMMER high SEA MID

SST Rhythm and Long-range Sea-ice Forecast

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Acta Oceanologica Sinica 1985年第1期 165-166页

作者：臧恒范王绍武 national Marine Environmental Forecasting Center national bureau of oceanography Beijing Department of Geophysics Peking University

In this note, the rhythm of sea surface temperature (SST) is studied. It is found thatover the North Pacific the summer (July to October), SST correlates well with the SST inwinter (January to March), which is called SST rhythm. It is shown that the SST rhythm links the summer SST in the North Pacific with thewinter sea--ice in the Bohai Sea. This relationship may be used to make long--range sea-ice prediction. Unfortunately the available series of sea--ice is too short. But the experience

关键词： SST Rhythm and Long-range Sea-ice Forecast over

A study on seismic source process in shortterm and imminent stage before destructive mining shock

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Acta Seismologica Sinica(English Edition) 1999年第1期12卷 63-72页

作者：刘万琴李世愚郑治真赵明沈萍 Institute of Geophysics China Seismological Bureau Beijing China national Center for Seismic Data and Information China Seismological Bureau Beijing China Beijing Seismological bureau Beijing China

Three destructive mining shocks successively occurred nearby the seismic Station No.6 located in a shaft of the Fangshan Coal Mine of Beijing Mining Service in 4 minutes at 19 o′clock of May 15, 1993. The largest shock is of M =2.3 ( M 0=1.5×10 11 N·m). Analysis of synthetic seismogram provides that the three shocks exhibited predominantly a dip slip movement mode, which is consistent with the collapse of coal mass from the coal bed at high dip angle, as observed by those who were present at the site. The near field records of the main shock and a series of events prior to it made at the Station No.6 are different from normal records, it had not only high frequency vibration, but also low frequency vibration. By using elastic wave theory and nucleation theory of seismic fracture during recent years, analysis of the data indicates that the low frequency vibration maybe long period wave as the subcritical extension is pushing forward. It is an unrecovered deformation. The high frequency vibration is just the mining shock event, exhibiting a wave field of brittle fracture radiation. From the dominant frequency of low frequency vibration in the records of M =2.3 event and the records of foreshocks at 5.4 s before it, it is inferred that the volume of dilatation zone at the termination of shock generating fracture has rapidly enlarged during the occurrence of the main shock. In 20 or more days before the main shock, the source process was of the following characteristics: the subcritical extension occurred for many times; during this period the volume of dilatation zone at the termination of shock generating fracture little changed. The subcritical extension not only exits long period waves, but also induced small events at the same time. The dominant orientation of subcritical extension is basically consistent with the direction of slip movement during main shock.

关键词： mining shock high frequency vibration low frequency vibration subcritical extension

Preferential feeding of an anthocorid predator Blaptostethus pallescens Poppius on different stages of cotton mealybug

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环境昆虫学报 2011年第4期33卷 423-428页

作者： Gupta Tripti national bureau of Agriculturally Important Insects (ICAR)

Blaptostethus pallescens Poppius (Heteroptera:Anthocoridae),which is amenable to mass rearing,has proved to be a potential predator of sucking pests like mites and ***,the cotton mealybug Phenacoccus solenopsis Tinsley emerged as a serious pest on cotton in *** studies indicated that *** could feed on the cotton ***,further investigations were conducted to understand the stage of the predator which is most potential and the pest stage preferred by the *** nymphs and adults of *** could predate equally well on the neonates of cotton *** (three to four-day-old) nymphs of the predator could not feed on any stage of the cotton *** nymphs (seven-day-old and above) and adults could effectively predate on both young and mature cotton mealybug crawlers,though preference was more for the younger ***,nymphs and adults of *** could not predate on the adult stage of the *** predator:pest ratios were tested in cage studies and it emerged that *** adults released against the mealybug crawlers at a ratio of 1:5 and nymphal release at 1:10 caused maximum mortality of the mealybug *** the fast multiplication rate of cotton mealybug and the large number of predators which have to be released to manage them,further detailed studies are necessary on utilizing *** to target the neonates and younger stages of the cotton mealybug in field conditions.

关键词： Anthocoridae Blaptostethus pallescens feeding potential host stage preference mealybug Phenacoccus solenopsis