The Operational Forecasting of Total Precipitation in Flood Seasons (April to September) of 5 Years (1983-1987)

Ⅰ.INTRODUCTION We have discovered that there exists a good corresponding relationship between theanomalous axes of soil temperature at a depth of 1.6m in winter (December to February) andprecipitations in following flood season (Tang et al., 1982a). We have also designed a simplethermodynamical model and applied it to the forecasting of precipitations in the flood season(Tang et al., 1982 b,c). The practical forecast started from 1975. Before 1980, however, therewere only 40-50 stations in China for measuring the soil temperature at a 1.6m depth. Since1980, the stations have been increased to a total of about 180, but no available mean valueshad been obtained from newly added stations before 1982. Therefore the analysis and map-ping of anomalies of soil temperature was not performed until 1983, and from then on theprecision of analysis has been greatly improved. The following is the actual situation of forecast in five years from 1983 to 1987.     

TM数据的Kauth-Thomas变换在盐渍土分析中的作用——以阳高盆地为例

本文就经过Kauth-Thomas变换的TM数据用于雁北阳高盆地盐渍化程度分析进行了探讨。通过模拟TM数据和TM影像数据进行变换分析,并与标准假彩色合成和K-L变换比较,取得了较好的结果。     

TL dating of malan loess in gansu province

TL dating technique is of great advantage for determining the initial time of storing energy (T₀) in an object to be analyzed. The sample is required to have undergone at least one thermal event, permitting all the residual storage to release. As a result, TL dating technique has found wide application in geochronology of pottery. The determination of T₀ of loess is mainly based on the fact that fine particles of which loess is composed will lose their storage in the process of transportation by wind. In our experiment TL dating technique was adopted to determine the ages of fine quartz grains, and the results were corrected for those of shine-fading experiment. TL dating of Malan loess specimens from Mt. Gaolanshan, Liugouhe near Lanzhou, Mt. Qijiadashan in Jingning and Baichaoyuan in Huining gave the age values of 2.6±0.1, 3.6±0,3. 4.7±0.5 and 10.0±0.6×10⁴ yr, respectively. The values indicate that the Malan loess began depositing in Late Pleisotocene, but the initial time and acumulation rate are different under different morphological conditions from place to place.     

EXPERIMENTAL GEOCHEMISTRY STUDY ON GOLD IN WATER-ROCK REACTION UNDER THERMAL FLUID SYSTEM AT MESO-LOW TEMPERATURE

Based on the knowing geochemical characteristics of wall rock in the Mobin gold deposit and composition of fluid inclusion in ore,water-rock experiments were carried out,important achievements are acquired as following: Gold is mainly derived from the ore-bearing wall rock,i,e.,a series of epimetamorphic clastic gritstone,sandy slate,and tuffaceous slate in the Wuqiang Banxi Formation,Wuqiangxi Group.In thermal system with middle-low temperature chlorine gold may be derived form stable complex ions,so it is quite important in gold metallogenic process.Sulphur and chlorine perform as the major negative ions throughout the gold activation and migration movement.The concentration of sulphur and chlorine ions,pH value and temperature are of deciding significance for gold activation,migration and precipitation.     

Lg amplitude ratios H/Z and station terms in the six eastern provinces of China

Using the data set of about 1 Hz Lg amplitudes from 80 stations in the six eastern provinces of China, the ratios of horizontal to vertical amplitude of Lg waves,H/Z are determined. The mean lg(H/Z)-value is equal to 0.13. For the station bases of soft deposit,granite and sedimentary rock, lg(H/Z)-values average 0.55, 0.04 and 0.10, respectively. For the three kinds of station bases, the station terms of horizontal amplitude,C _h average 0.65, −0.09 and 0.00; that of vertical amplitude,C _z average 0.32, −0.04 and 0.00, respectively. There are the relations betweenC _h ,C _z and lg(H/Z):C _h =0.01+2.10C _z andC _h =−0.15+1.46 lg(H/Z). The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,13, 281–286, 1991. Project sponsored by the Chinese Joint Seismological Science Foundation.     

臭牛沟组命名剖面上的生物化石分布

生物地理区系的形成与演化,是研究古板块位置,漂移方向和会聚过程的有效标志,但生物地理区系的划分又必须在严格的年代地层对比基础上进行。作者经数次的野外剖面测制,收集各类化石标本加以研究。同时广泛收集前人化石研究成果,经仔细核实研究,确定了臭牛沟组命名剖面上的生物化石分布实况。进一步证明臭牛沟组是一个跨统的岩石地层单位,上、下石炭统的界线在其上部通过。     

利用马氏过程模拟和预测土壤侵蚀的动态演变─—以安徽省岳西县为例

本文根据安徽省岳西县１９５８－１９８２－１９９２年三个时期的遥感资料所编制的土壤侵蚀图，用点数转化法定量地分析岳西县上述两个阶段侵蚀演变和浸蚀类型之间的相互转化状况，确定相应的初始状态下（１９５８和１９８２）的转移概率矩阵，应用马尔科夫过程摸拟和预测岳西县土壤侵蚀及其格局的动态演变过程和未来演变趋势。     

Propagation of disturbances in the solar chromosphere and corona (II)

The first part of this article presents an analytic discussion of the linear properties of magnetohydrodynamic (MHD) wave propagation. Then, with a 2-dimensional, time-dependent, compressible MHD simulation subject to a self-consistent non-isothermal, non-uniform initial state, we study numerically the global propagation process following an initial pressure pulse applied at the base of the chromosphere. Our numerical results indicate that, if the pulse is applied near the pole, there are two modes, one fast, one slow of magnetoacoustic waves; whereas if the pressure pulse is applied near the equator, there is a fast mode and a standing disturbance located near the source. These results may help interpret the wave events observed by SOHO/EIT.     

DIAGNOSIS ON LOW FREQUENCY COMPONENT OF ENSO VARIABILITY—PART Ⅱ:ORIGIN OF THE COMPONENT

Diagnosis is undertaken on the origin for the low-frequency component (LFC) of ENSOvariability in the context of 1979—1990 OLR and u-wind datasets.Evidence suggests that ① apower spectrum-yielded maximum,significant statistically,is derived from the OLR monthlyanomalies in a 3—5-year period range over the tropical central/western Pacific;②compositeanalysis of the signals of the monthly anomaly low frequency component (period>3 years)confirms further the dynamic features of the component as documented in Part Ⅰ:③serving asforcing on ENSO,the related monsoon region represents the source area of the component;④theone-point correlation maps of unfiltered OLR monthly anomalies with zonal wind on a lagged,asimultaneous and a leading basis show clearly the close relation between the u wind-associatedeastward travelling low-frequency wave and the low-frequency oscillation of low-latitude central/western Pacific large-scale convection and the east-moving mode is likely to be excited by theoscillation at a 3—5-year period range.It follows that the large-scale convection oscillation showsup as the origin of the eastward waves,i.e.,ENSO LFC.     

ON BROADENING MECHANISMS OF THE Ca XIX RESONANCE LINE IN SOLAR FLARES

There are two explanations for the broadening mechanisms of the Caxix resonance line in the rising phase of a solar flare. One is due to the velocity dispersion of the chromospheric evaporation along the loop; the other is due to the non-thermal turbulence resulting from the flare energy release. In this paper we distinguish between these two possibilities by studying the influence of the loop orientation on the broadening of the Caxix resonance line, based on the data observed with SXT and BCS on Yohkoh. The results seem to support that the broadening of the Caxix resonance line is caused by non-thermal turbulence, rather than by the velocity dispersion.