湖南土壤的地理分布规律

湖南属于中亚热带常绿阔叶林红壤地带.境内自然条件复杂,从而影响红壤的发商和分布具有水平分布规律;东、南、西三面环山,土壤的发生和分布显示着明显的垂直分布规律(即红壤—黄红壤—山地黄壤—山地黄棕壤—山地灌丛草甸土)。加以非地带性因素的影响,还具有多种结构形式的区域分市规律。研究和分析土壤地理分布规律,对土壤资源的综合开发利用具有重要的现实意义。     

Occurrence of two types of El Niño events and the subsurface ocean temperature anomalies in the equatorial Pacific

The relationships between the evolution of two types of E1 Nifio events and the subsurface ocean temperature anomaly （SOTA） in the equatorial Pacific are compared in this study. The results show that both types of E1 Nifio are negatively correlated to the SOTA in the equatorial western Pacific, but relationships are different in different phases of E1 Nifio. Furthermore, the occurrence of different types of E1 Nifio is related to different features of the equatorial thermocline, e.g. its zonal gradient, significant variation area, amplitude and duration of thermocline oscillation. The propagation of SOTA in the equator plays an important role during the evolution of both types of E1 Nifio, but shows dramatic differences in intensity, duration and phase reverse of warm SOTA. Moreover, the pathways of SOTA signal are different between these two types of E1 Nifio. The dominant pathway in the life cycle of Eastern Pacific （EP）-E1 Nifio lies on the equator and to its north, but there is no loop to the south of the equator. In contrast, the dominant pathway in Central Pacific （CP）-E1 Nifio is located on the equator and to its south, and the propagation signal of SOTA to the north of the equator is very weak. The relationships between the zonal wind anomalies and the two types of E1 Nifio are also preliminarily discussed. It is shown that EP-E1 Nifio is more likely to respond to the westerly anomalies over the equatorial central and western Pacific, while CP-E1 Nifio is more likely to respond to the westerly anomalies over the equatorial western Pacific and need the cooperation of easterly anomalies over the equa- torial eastern Pacific to certain extent.     

冲压增程弹用进气道试验与数值研究

对某冲压增程弹用超声速双锥进气道流场特性进行研究,在风洞试验中得到合理的流场结构图谱及试验数据.采用块结构网格与二阶精度流场分区求解技术,对该超声速进气道内外流场进行数值研究.通过数值模拟得到了对应于不同出口反压和攻角情况下,超声速进气道内外粘性流场复杂的波系结构,分析了进气道内外流场的形成过程.结果表明:数值模拟得到的流场结构波系图与风洞试验纹影图一致,并且进气道扩压段静压分布以及进气道出口位置的总压分布与试验结果基本一致.     

浙西龙王山植被在地带性植被中的地位探讨

龙王山位于浙江西北部的安吉县境内,紧邻临安天目山,北纬30°22',东经119°27'.它是天目山脉的主要山峰之一,主峰海拔1587.4m,比西天目山略高,整个保护区的面积为1.8万亩.通过对龙王山植物区系、群落特征、气象资料以及栽培植物的分布状况等方面的分析,论证了龙王山植被倾向于中亚热带性质,并肯定其向北亚热带过渡的过渡性地位.