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Hedychium menghaiense (Zingiberaceae),a new species from Yunnan,china

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Journal of Systematics and Evolution 2010年第2期48卷 146-151页

作者： 1,2,3Xiu HU 1Nian LIU 1(Zhongkai University of Agriculture and Engineering,Guangzhou 510225,china) 2(South china Botanical Garden,Chinese academy of Sciences,Guangzhou 510650,china) 3(Graduate School of Chinese academy of Sciences,Beijing 100049,china) (Zhongkai University of Agriculture and Engineering Guangzhou 510225 China) (South china Botanical Garden Chinese Academy of Sciences Guangzhou 510650 China) (Graduate School of Chinese academy of Sciences Beijing 100049 China)

Hedychium menghaiense *** & ***,a new species of the Zingiberaceae from Yunnan Province,china,is described and *** new species is currently known only from its type locality,Nannuoshan Mountain,Menghai County,growing under evergreen broad-leaved forests at altitudes of 1400-1700 *** is similar to Hedychium forrestii Diels,but differs in its narrower and emarginate labellum folded inwards lengthwise,narrower staminodes,and scarlet *** recognition of the new species is supported by the results from analysis of sequence-related amplified polymorphism markers.

关键词： Hedychium Hedychium menghaiense X.Hu & N.Liu new species SRAP markers Zingiberaceae

Quantitative Relationship Between Land Use and Phosphorus Discharge in Subtropical Hilly Regions of china

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Pedosphere 2003年第1期13卷 67-74页

作者： YANG JINLING and ZHANG GANLINInstitute of Soil Science, the Chinese academy of Sciences, Nanjing 210008 (china) Institute of Soil Science the Chinese Academy of Sciences Nanjing 210008 (China)

The increase of phosphorus concentration is a crucial factor causing the eutrophication of water body,while land use has an important impact on agricultural non-point sources (NPS) phosphorus discharge. Sevensites controlling the water in four sub-watersheds and the main exit of the Meicun Watershed of XuanchengCounty, Anhui Province, were investigated by dynamic monitoring of stream water and nutrient discharge,integrating interpretation of aerial image and GIS analysis to find out how the land use affects phosphorusloss with stream water in typical agriculture-forest watershed in subtropical china. These monitored sitesare different in structure of land use. Phosphorus concentration of the stream water was analyzed everyweek and at the next day of rainfall. The velocity of flow was measured by kinemometer to calculatethe runoff flux and phosphorus discharge. The results showed that the runoff flux and the discharges ofdissolved phosphorus (DP), particle-associated phosphorus (PAP) and total phosphorus (TP) had significantexponential relationships with the area percentages of forest, pond and paddy field. There existed a significantlinear relationship between the TP and PAP concentrations in stream water and the area percentages of forest,pond and paddy field, and the discharge of PAP was also significantly linearly correlated with the dischargeof suspended soil particles. There was a logarithmic linear relationship between DP and PAP discharges. Thestudy indicated that the adjustment of land use patterns and construction of ecologically sound landscapewould be an important measure to reduce the runoff discharge of phosphorus. The results would be veryuseful in building the best management practices (BMPs) of agricultural watershed in subtropics.

关键词： land use phosphorus runoff watershed

BIFURCATION OF THE NORTH EQUATORIAL CURRENT DERIVED FROM ALTIMETRY IN THE PACIFIC OCEAN

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Journal of Hydrodynamics 2006年第5期18卷 620-626页

作者： WANG Qing-ye HU Dun-xin Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of the Chinese academy of Sciences Beijing 100039 China

The gridded （1/3°＊1/3°） altimetry data from October 1992 through December 2004 were analyzed to study the seasonal and interannual variabilities of the bifurcation of the North Equatorial Current （NEC） at the surface in the western North Pacific Ocean. Calculations show that on annual average the bifurcation occurs at about 13.4°N at the surface. The geostrophic flow derived from Sea Surface Height （SSH） data shows that the southernmost latitude of the NEC bifurcation at the surface is about 12.9°N in June and the northernmost latitude is about 14.1°N in December. Correlation analyses between the bifurcation latitude and the Southern Oscillation Index （SOl） suggest that the bifurcation latitude is highly correlated with the E1 Nino/Southern Oscillation （ENSO） events. During the E1 Nino years the bifurcation of the NEC takes place at higher latitudes and vice versa.

关键词： bifurcation of the North Equatorial Current altimetry data Pacific Ocean North Equatorial Current (NEC),E1 Nino/Southern Oscillation (ENSO) events

^(14)C measurement of forest soils in Dinghushan Biosphere Reserve

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Chinese Science Bulletin 1999年第3期44卷 251-256页

作者： SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi Guangzhou Institute of Geochemisry, Chinese academy of Sciences, Guangzhou 510640, china Institute of Geology, Chinese academy of Sciences , Beijing 100029, china South china Institute of Botany, Chinese academy of Sciences, Guangzhou 510650, china Guannzhou Institute of Geochemisry Chinese Academy of Sciences Guanazhou China Institute of Geology Chinese Academy of Sciences Beijing China South china Institute of Botany Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14C values of these profiles decrease with increasing of depth. The Δ14C values in 30—40 cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 425 a BP, which is consistent with historical documents. The penetrating depths of "bomb 14C" in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively.

关键词： Dinghushan forest soil 14C tracing 14C apparent age.

Ionization state of cosmic hydrogen by early stars and quasars

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Research in Astronomy and Astrophysics 2009年第6期9卷 665-681页

作者： Xiao-Chun Mao1,2 1 National Astronomical Observatories, Chinese academy of Sciences, Beijing 100012, china 2 Graduate University of Chinese academy of Sciences, Beijing 100049, china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of Chinese academy of Sciences Beijing 100049 China

Cosmic hydrogen is reionized and maintained in its highly ionized state by the ultraviolet emission attributed to an early generation of stars and quasars. The Lyα opacity observed in absorption spectra of high-redshift quasars permits more stringent constraints on the ionization state of cosmic hydrogen. Based on density perturbation and structure formation theory, we develop an analytic model to trace the evolution of the ionization state in the post-overlap epoch of reionization, in which the bias factor is taken into account. For quasars, we represent an improved luminosity function by utilizing a hybrid approach for the halo formation rate that is in reasonable agreement with the published measurements at 2 ≤ z ≤ 6. Comparison with the classic Press-Schechter mass function of dark matter halos, we demonstrate that the biased mass distribution indeed enhances star formation efficiency in the overdense environment by more than 25 per cent following the overlap of ionized bubbles. In addition, an alternative way is introduced to derive robust estimates of the mean free path for ionizing photons. In our model, star-forming galaxies are likely to dominate the ionizing background radiation beyond z = 3, and quasars contribute equally above a redshift of z ～ 2.5. From 5 ≤ z ≤ 6, the lack of evolution in photoionization rate can thus be explained by the relatively flat evolution in star formation efficiency, although the mean free path of ionizing photons increases rapidly. Moreover, in the redshift interval z ～ 2 - 6, the expected mean free path and Gunn-Peterson optical depth obviously evolve by a factor of ～ 500 and ～50 respectively. We find that the relative values of critical overdensities for hydrogen ionization and collapse could be 430% at z ≈2 and 2% at z ≈6, suggesting a rapid overlap process in the overdense regions around instant quasars following reionization. We further illustrate that the absolute estimates of the fraction of neutral hydrogen computed fr

关键词： cosmology theory -- formation galaxies -- quasars general -- diffuse radiation -- intergalactic medium

Explicit formula of holomorphic automorphism group on complex homogeneous bounded domains

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Science china Mathematics 2006年第10期49卷 1392-1404页

作者： XU Yichao,CHEN Minru & MA Songya academy of Mathematics and Systems Science, Chinese academy of Sciences, Beijing 100080, china College of Mathematics and Information Sciences, Henan University, Kaifeng 475001, china academy of Mathematics Systems Science Chinese Academy of Sciences Beijing 100080 China College of Mathematics Information Sciences Henan University Kaifeng 475001 China

We known that the maximal connected holomorphic automorphism group Aut (D)(0) is a semi-direct product of the triangle group T(D) and the maximal connected isotropic subgroup Iso (D)(0) of a fixed point in the complex homogeneous bounded domain D and any complex homogeneous bounded domain is holomorphic isomorphic to a normal Siegel domain D(VN,F).In this paper, we give the explicit formula of any holomorphic automorphism in T(D(VN,F)) and Iso (D(VN, F))(0), where G(0) is the unit connected component of the Lie group G.

关键词： holomorphic automorphism group, homogeneous Siegel domain, normal Siegel domain, complex homogeneous bounded domain.

A preliminary study on the heat storage fluxes of a tropical seasonal rain forest in Xishuangbanna

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Science china Earth Sciences 2006年第S2期49卷 163-173页

作者： DOU Junxia, ZHANG Yiping, YU Guirui, ZHAO Shuangju, WANG Xin & SONG Qinghai Xishuangbanna Tropical Botanical Garden, Chinese academy of Sciences, Kunming 650223, china Institute of Geographic Sciences and National Resources Research, Chinese academy of Sciences, Beijing 100101, china Research Centre for Eco-environmental Sciences, Chinese academy of Sciences, Beijing 100085, china Graduate University of the Chinese academy of Sciences, Beijing 100049, china 1. Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Kunming 650223 China3. Research Centre for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China4. Graduate University of the Chinese Academy of Sciences Beijing 100049 China2. Institute of Geographic Sciences and National Resources Research Chinese Academy of Sciences Beijing 100101 China

In order to discuss the values and daily variation characteristics of heat storage fluxes in a tropical seasonal rain forest in Xishuangbanna, the sensible and latent heat storage flux within air column, canopy heat storage flux, energy storage by photosynthesis and ground heat storage above the soil heat flux plate, as well as the ratios of these heat storage fluxes to the net radiation in the cool-dry, hot-dry and rainy season were compared and analyzed based on the observation data of carbon fluxes, meteorological factors and biomass within this tropical seasonal rain forest from January 2003 to December 2004. The findings showed that heat storage terms ranged significantly in the daytime and weakly in the nighttime, and the absolute values of sensible and latent heat storage fluxes were obviously greater than other heat storage terms in all seasons. In addition, the absolute values of total heat storage fluxes reached the peak in the hot-dry season, then were higher in the rainy season, and reached the minimum in the cool-dry season. The ratios of heat storage fluxes to net radiation generally decreased with time in the daytime, moreover, the sensible and latent heat storage dominated a considerable fraction of net radiation, while other heat storage contents occupied a smaller fraction of the net radiation and the peak value was not above 3.5%. In the daytime, the ratios of the total heat storage to net radiation were greater and differences in these ratios were distinct among seasons before 12:00, and then they became lower and differences were small among seasons after 12:00. The energy closure was improved when the storage terms were considered in the energy balance, which indicated that heat storage terms should not been neglected. The energy closure of tropical seasonal rain forest was not very well due to effects of many factors. The results would help us to further understand energy transfer and mass exchange between tropical forest and atmosphere. Moreo

关键词： heat storage flux energy closure tropical seasonal rain forest Xlshuangbanna.

Finding Signals for Plant Promoters

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Genomics, Proteomics & Bioinformatics 2003年第1期1卷 68-73页

作者： Weimou ZhengInstitute of Theoretical Physics, Chinese academy of Sciences, Beijing 100080, china Beijing GenomicsInstitute, Chinese academy of Sciences, Beijing 101300, china Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China Beijing Genomics Institute Chinese Academy of Sciences Beijing 101300 China

The strongest signal of plant promoter is searched with the model of single motif with two types. It turns out that the dominant type is the TATA-box. The other type may be called TATA-less signal, and may be used in gene finders for promoter recognition. While the TATA signals are very close for the monocot and the dicot, their TATA-less signals are significantly different. A general and flexible multi-motif model is also proposed for promoter analysis based on dynamic programming. By extending the Gibbs sampler to the dynamic programming and introducing temperature, an efficient algorithm is developed for searching signals in plant promoters.

关键词： for on is as et Pro Finding Signals for Plant Promoters been of into

Poisson kernel and Cauchy formula of a non-symmetric transitive domain

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Science china Mathematics 2010年第7期53卷 1678-1683页

作者： LU Qi-Keng Institute of Mathematics, academy of Mathematics and System Science, Chinese academy of Sciences, Beijing 100190, china Institute of Mathematics Academy of Mathematics and System Science Chinese Academy of Sciences Beijing China

In 1965, Lu Yu-Qian discovered that the Poisson kernel of the homogenous domain S m,p,q={Z∈Cm×m, Z1∈Cm×p,Z2 ∈Cq×m|2i1( Z-Z+)-Z1Z1′-Z2′Z2>0} does not satisfy the Laplace-Beltrami equation associated with the Bergman metric when S m,p,q is not symmetric. However the map T0:Z→Z, Z1→Z1 , Z2→Z2 transforms S m,p,q into a domain S I (m, m + p + q) which can be mapped by the Cayley transformation into the classical domains R I (m, m + p + q). The pull back of the Bergman metric of R I (m, m + p + q) to S m,p,q is a Riemann metric ds 2 which is not a Khler metric and even not a Hermitian metric in general. It is proved that the Laplace-Beltrami operator associated with the metric ds 2 when it acts on the Poisson kernel of S m,p,q equals 0. Consequently, the Cauchy formula of S m,p,q can be obtained from the Poisson formula.

关键词： Poisson kernel Cauchy formula